ROUTING AND TRANSMITTAL SLIP Date

TO: (Name, office symbol, room number'

4.

5. File Note lind Return For Clearance Per Conversation For Correction Prepare Reply For Your Information See Me Investigate. ignature Justify

hA-V.f!.: 6~en. .~

FROM: (Nam8l1..j)jrg.,.,

*U.SG" ". PO"199'3' ""~ 342-198180007 . ENVIRONMENTAL PROTECTION AGENCY REGION III 1650 Arch Street Philadelphia, Pennsylvania 19103-2029

DATE:

Department of the US Air Force Kenneth R.Rizer, th ' Commander, 11 MAY 1 7 2011 1535 Command Drive " Suite A-B 203 , lointBase Andrews, MD 20762

RE: 2010 (Revised March 2011) Five-Year Review Andrews (Previously ) Clinton,

Dear Colonel Rizer:

, , , Thank you for submitting the report, entitled First Five-Year Review NavalAir Facility Washington, NFA8903-08-D-8775, Delivery Order 52, November 2010 (Revised March 2011) to the EPA for review and concurrence. The report was prepared to address the Comprehensive Environmental" Response, Compensation and ,Liability Act (CERCLA) Section 121 (c) five-year review requirements. ·EPA has reviewed this five-year review report and found it consistent with EPA's June 2001 guidance document, Comprehensive Five Year Review Guidance (OSWERNo. 9355.7-03B-P, EPA 540-R-OI-007).

EPA concurs with the US Air Force's determination that the remedies for FT-04,ST-IO~ and ST-14are protective of human health and the environment. In addition, Site 23 had a no action record of decision (ROD) and is protective. Furthermore, as part of this five-year review, EPA has evaluated the Government Performance and Results Act (GPRA) measures for this site and has determined their status is as follows:

Environmental Indicators l.Human Health: Current Exposure Controlled , Groundwater Migration:' Groundwater' Migration Is Under Control, specifically for LF;.05 Leroy's Lane Landfill. ,The remedy was being implemented when the Five­ Year Review, was written. There is no completed pathway for human, health and/or the environment. The remedy at LF-05 is anticipated to be complete in 2011 with issua'1ce ofa remedial action completion report (RACR)/or the landfillcapandan interim rem~dial action completion report (IRACR) for groundwater. "

{) Printed on 100% recycled/recyclable paper with 100% post-consumer fiber and process chlorine/ree. , Customer Service Hotline: 1-800-438-2474 .Sitewide Ready for Anticipated Use

Joint Base Andrews is Site-Wide Ready for Anticipated Use.

The requirement for this five-year review at Joint Base Andrews (formerly Andrews Air Force Base) was triggered by the Remedial Action start date and ROD date of November 22, 2005 at FT..:04. The next five-year review is due five years from the original due date and is due November 22,2015.

If you have any questions, please contact Ben Mykijewycz, Chief of the NPLIBRAC Federal Facilities Branch at 215-814-3351 or S Andrew Sochanskiat (215) 814-3370 or at [email protected].

cc: S Andrew Sochanski (3HS11) Rick Grills,MDE W AS/EERP William Burris, Chief, ER JBA

o .Printed on 100% recycled/recyclable paperwitll 100% post-consumer fiber and process clllorine free. Customer Se,y;ce Hotline: 1-800-438-2474 FIRST FIVE-YEAR REVIEW

JOINT BASE ANDREWS NAVAL AIR FACILITY WASHINGTON

Prepared for:- The Air Force Center for Engineering and the Environment

Contract No. FA8903-08-D-8775 Delivery Order 52

Prepared by: IlMACTEC MACTEC Engineering and Consulting, Inc. Portland, Maine

November 2010 (Revised March 2011) FIRST FIVE-YEAR REVIEW

JOINT BASE ANDREWS . NAVAL AIR FACILITY WASHINGTON

United States Air Force

Prepared for: The Air Force Center for Engineering and the Environment Contract No. FAS903-0S-D-S775 Delivery Order 52

Prepared by: ,MACTEC MACTEC Engineering and Consulting, Inc. Portland, Maine

November 2010 (Revised March 2011) • • FIRST FIVE-YEAR REVIEW

JOINT BASE ANDREWS NAVAL AIR FACILITY WASHINGTON

PreparedJor: The Air Force Center for Engineering and the Environment Contract No. F A8903-08-D-8775 Delivery Order 52

Prepared by: MACTEC Engineering and Consulting, Inc. Portland, Maine

November 2010 (Revised March 2011)

. S;nley.W.Rccd· .. - Principal Engineer MACTEC Engineering & Consulting, Inc. Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011) ,

TABLE OF CONTENTS

LIST OF FIGURES ...... viii • LIST OF TABLES ...... ix LIST OF APPENDICES...... •...... x LIST OF ACRONYMS AND ABBREVIATIONS ...... · ..... xi 1.0 INTRODUCTION ...... 1 1.1 PURPOSE AND SCOPE ...... 1 1.2 JOINT BASE ANDREWS HISTORY AND DESCRIPTION ...... 2 1.2.1 History...... :...... 2 1.2.2 Topography ...... : ...... 4 1.2.3 ·Climate ...... ,...... 4 1.2.4 Soil and Drainage ...... 5 1.2.5 Geology ...... 5 1.2.6 Groundwater...... 6 1.2.7 Current and Anticipated Future Land Use ...... ~ ...... 6 1.3 REFERENCES ...... , ...... ,...... 8 2.0 FT-04 FIVE-YEAR REVIEW ...... 9 2.1 FT-04 DESCRIPTION AND CHRONOLOGY...... : ...... 9 2~2 FT-04 BACKGROUND ...... 10 2.2.1 Physical Characteristics ...... ~ .... 10 2.2.2 Land and Resource Use ...... : ...... ,...... 11 .2.2.3 History of Contamination...... ~ ...... 11 2.2.4 Initial Response ...... , ...... , ...... 13 2.2:5 Basis for Taking Action ...... 16 • 2.3 FT-04 REMEDIAL ACTIONS ...... :...... 16 2.3.1 Remedial Action Objectives ...... 17 2.3.2 The Selected Remedy ...... ·...... ;...... 17 2.3.3 Remedy Implementation ...... , ...... ;...... 21 2.3.4 System Operations/Operation and Maintenance ...... 22 2.4 FT-04 PROGRESS SINCE FIRST FIVE-YEAR REVIEW ...... 22 2.5 FT-04 FIVE-YEAR REVIEW PROCESS ...... 22 2.5.1 Community Involvement ...... ,...... 22 2.5.2 Document Review ...... 22 2.5.3 Applicable or Relevant and Appropriate Requirement Review ...... , ...... 23 2.5.4 Data Review ...... 23 2.5.5 Site Inspection ...... , ...... :...... 27 2.5.6 Interviews ...... :...... 27 2.6 FT-04 TECHNICAL ASSESSMENT ...... 28 2.6.1 Question A: Is the remedy functioning as intended by the decision documents? ...... 28 2.6.2 Question B: Are the exposure assumptions, toxicity data, cleanup levels, and RAOs used at the time of the remedy still valid? ...... , 30 2.6:3 Question C: Has any other information come to lightthat could call into question the protectiveness of the remedy? ...... 3 3 2.6.4 Technical Assessment Summary ...... 33 2.7 FT-04 ISSUES ..... : ...... 34 2.8 FT-04 RECOMMENDATIONS AND FOLLOW-UP ACTIONS ...... 34 2.9 FT-04 PROTECTIVENESS STATEMENT ...... 34 • 2.10 FT -04 NEXT REVIEW ...... 34 P:\Projects\Andrews AFB EnvironmentalIFive-year reviews\4.0 _ Deliverables\4.1_ ReportslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

TABLE OF CONTENTS 2.11 FT-04REFERENCES ...... 35 • 3.0 ST-IO FIVE-YEAR REVIEW ...... 37 3.l ST-IO DESCRIPTION AND CHRONOLOGY ...... 37 3.2 ST-lO·BACKGROUND ...... ,...... 39 3.2.1 Physical Characteristics ...... 39 . 3.2.2 Land and Resource Use ...... 39 3.2.3 History of Contamination...... 40 3.2.4 Initial Response ...... ~ ...... : ...... 43 3.2.5 Basis for Taking Action ...... 43 3.3 ST-IO REMEDIAL ACTIONS ...... 44 3.3.1' Remedial Action Objectives ...... 44 3.3.2 . The Selected Remedy ...... ;...... 44 3.3.3 Remedy Implementation ...... ,...... 50 3.3.4 System Operations/Operation and Maintenance ...... ,...... 51 3.4 ST-IO PROGRESS SINCE LAST FIVE-YEAR REVIEW ...... ,51 3.5 ST-I0 FIVE-YEAR REVIEW PROCESS ...... :...... 51 3.5.1 Community Involvement ...... 51 3.5.2 Document Review ...... 52 3.5.3 Applicable or Relevant and Appropriate Requirement Review ...... 52 3.5.4 Data Review ...... 52 3.5.5 Site Inspection ...... 55 3.5.6 Interviews ...... 55 3.6 ST-IO TECHNICAL ASSESSMENT ...... :...... 55 3.6.1 Question A: Is the remedy functioning as intended by the decision documents? .. :..... 55 3.6.2 Question B: Are the exposure assumptions, toxicity data, cleanup levels, and RAOs used at the time of the remedy still valid? ...... ,57 3:6.3 Question C: Has any other information come to light that could call into • question the protectiveness of the remedy? ...... , ...... 59 3.6.4 Technical Assessment Summary ...... 59 '3.7 ST-I0 ISSUES ...... 59 3.8 ST-I0 RECOMMENDATIONS AND FOLLOW-UP ACTIONS ...... 60 3.9 ST-IO PROTECTIVENESS STATEMENT ...... 61 3.10 ST-I0 NEXT REVIEW ...... 61 3.11 ST-I0 REFERENCES ...... 61 4.0 'ST-14 FIVE-YEAR REVIEW ...... 63 4.1 ST-14 DESCRIPTION AND CHRONOLOGY...... 63 4.2 ST-14 BACKGROUND ...... 64 4.2.1 Physical Characteristics ...... 64 4.2.2 Land and Resource Use ...... 65 4.2.3 History of Contamination...... 66 4.2.4 Initial·Response ...... 72 4.2.5 Basis for Taking Action ...... 72 4.3 ST-14 REMEDIAL ACTIONS ...... 72 4.3.1 Remedial Action Objectives ...... ;...... 73 4.3.2 The Selected Remedy ...... 73 4.3.3 Remedy Implementation ...... 81 4.3 4 System Operations/Operation and Maintenance ...... 81 4.4 ST -14 PROGRESS SINCE LAST FIVE-YEAR REVIEW ...... 82 • 4.5 ST-14 FIVE-YEAR REVIEW PROCESS ...... 82

11

P:lProjectslAndrews AFB EnvironmentallFive-year reviewsI4.0_ DeliverablesI4.1_ ReportslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Alldrews - First Five-Year Review r November 2010 MACTEC Engineering and Consulting,Inc. Project Number 3350092494 (Revised March 2011)

TABLE OF CONTENTS 4.5.1 Community Involvement ...... 82 4.5.2 Document Review ...... 82 • 4.5.3 Applicable or Relevant and Appropriate Requirement Review ...... 83 4.5.4 Data Review ...... 83 4.5.5 Site Inspection ...... 91 4.5.6 Interviews ...... :...... 91 4;6 ST:-14 TECHNICAL ASSESSMENT ...... 91 4.6.1 Question A: Is the remedy functioning as intended by the decision documents? ...... 91 4.6.2 Question B: Are the exposure assumptions, toxicity data, cleanup levels, and RAOs used at the time of the remedy still valid? ...... 94 4.6.3 Question C: Has any other information come to light that could call into question the protectiveness of the remedy? ...... 96 4.6.4 Technical Assessrrient Summary , ...... 96 4.7 ST -14 ISSUES.; ...... ~ ...... 97 4.8 ST-14 RECOMMENDATIONS AND FOLLOW-UP ACTIONS ...... 98 4.9 ST-14 PROTECTIVENESS STATEMENT ...... 98 4.10 ST-14 NEXT REVIEW ...... 98 4.11 ST-14 REFERENCES ...... 98 5.0 SD-23 FIVE-YEAR STATUS RE·VIEW ...... 100 5.1 SD~23 DESCRIPTION AND CHRONOLOGY ...... 100 5.2 SD.-23 BACKGROUND ...... 101 52.1 Physical Characteristics ...... : ...... 101 5.2.2 Land and Resource Use ...... 101 52.3 History of Contamination...... 102 5.2.4 Initial Response ...... 106 5.2.5 Basis for No Action ...... 106 5.3 SD-23 THE SELECTED REMEDY ...... 106 '5.4 SD-23 PROGRESS SINCE LAST FIVE-YEAR REVIEW ...... 106 5.5 SD-23 FIVE-YEAR REVIEW PROCESS ...... 107 5.5.1 Community Involvement ...... :..... 107 5.5.2 Document Review ...... 107 5.5.3 Applicable or Relevant and Appropriate Requirement Review ...... 107 5.5.4 Data Review ...... 107 5.5.5 .Site Inspectioll' ...... ~ ...... , ...... 108 5.5.6 Interviews ...... 108 5.6 SD-23 TECHNICAL ASSESSMENT ...... 108 5:6.1 Question A: Is the remedy functioning as intended by the decision documents? ...... 108 5.6.2 Question B: Are the exposure assumptions, toxicity data, cleanup levels, and remedial action objectives used at the time of the remedy still valid? ...... 109 5.6.3 Question C: Has any other information come to light that could call into question the protectiveness of the remedy? ...... 109 5.6.4 Technical Assessment Summary ...... 109 5.7 SD-23 ISSUES ...... 109 5.8 SD-23 RECOMMENDATIONS AND FOLLOW-UP ACTIONS ...... 109 5.9 SD-23 PROTECTIVENESS STATEMENT ...... 109 5.10' SD-23 NEXT REVIEW ...... 109 5.11 SD-23 REFERENCES ...... 110 6.0 FT-02 FIVE-YEAR STATUS REVIEW...... 111 6.1 FT-02 DESCRIPTION AND CHRONOLOGY ...... 111 • 111 P:\ProjectslAndrews AFB Environmental\Five·year reviews\4.0_ Oeliverables\4.1_ Reports\FinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, fnc. Project Number 3350092494 (Revised March 2011)

TABLE OF CONTENTS 6.2 FT -02 BACKGROUND ...... 112 6.2.1 Physical Characteristics ...... 112 6.2.2 Land and Resource Use ...... · ...... ;..... 113 .' 6.2.3 History of Contamination...... , ...... 114 6.2.4 Initial Response ...... ·...... ·.... 115 6.2.5 BasisJor Taking Action ...... 115 6.3 FT-02 REMEDIAL ACTIONS ...... 116 6.3.1 Remedial Action Objectives ...... :...... 116 6.3.2 The Selected Remedy ...... , ...... 117 6.3.3' Remedy Implementation ...... 121 6.3.4 System Operations/Operation and Maintenance ...... :...... 121 6.4 FT-02 PROGRESS SINCE LAST FIVE-YEAR REVIEW ...... 121 6.5 FT-02 FIVE-YEAR STATUS REVIEW PROCESS ...... :...... 122 6.5.1 'Community Involvement ...... 122 6.5.2 Document Review· ...... ,...... 122 6.5.3 Applicable or Relevant and Appropriate Requirement Review ...... 122 6.5.4 Data Review ...... 123 6.5.5 Site Inspection ...... 123 6.5.6 Interviews ..... ;...... ;...... :...... 123 6.6 FT-02 TECHNICAL ASSESSMENT ...... ,...... 123 6.6.1 Question A: Is the remedy functioning as intended by the decision documents?...... 123 6.6.2 Question B: Are the exposure assumptions, toxicity data, cleanup levels, and remeqial action objeCtives used at the time of the remedy still valid? ...... 124 6.6.3 Question C: Has any other information come to light that could tall into question the protectiveness of the remedy? ...... ~ ...... 124 6.7 FT-02 ISSUES ...... 125 6.8 FT-02 RECOMMENDATIONS AND FOLLOW-UP ACTIONS ...... 125 6.9 FT-02PROTECTIVENESS STATEMENT ...... :...... 125 6.10 FT -02 NEXT REVIEW ...... 125 6.11 FT-02'REFERENCES ...... 125 7.0 FT-03 FIVE-YEAR STATUS REVIEW ...... •...... :.... 127 7.1 FT-03 DESCRIPTION AND CHRONOLOGY ...... 127 7:2 FT-03 BACKGROUND.; ...... 129 7.2.1 Physical Characteristics ...... :...... 129 I 7.2.2 Land and Resource Use ...... 130 7.2.3 History of Contamination...... ,...... 130 7:2.4 . Initial Response ...... 132 7.2.5 Basis for Taking Action ...... 132 7.3 FT-03 REMEDIAL ACTIONS ...... 132 7.3.1 Remedial Action Objectives ...... 133 7.3.2 The Selected Remedy ...... 134 7.3.3 Remedy Implementation ...... 137 7.3.4 System Operations/Operation and Maintenance ...... 137 7.4 FT-03 PROGRESS SINCE LAST FIVE-YEAR REVIEW ...... 137 7.5 FT-03 FIVE-YEAR STATUS REVIEW PROCESS ...... 137 7.5.1 Community Involvement ...... 137 7.5.2 Document Review ...... 138 7.5.3 Applicable or Relevant and Appropriate Requirement Review ...... 138 7.5.4 Data Review ...... 138 iv • P:\Projects\Andrews AFB EnvironmentallFive·year reviewsI4.0_DeliverablesI4.1_ ReportslFinal\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 201 I)

T ABLE OF CONTENTS 7.S.S Site Inspection ...... 139· 7.S.6 Interviews ...... ~ ...... :...... 139 • 7.6 FT-03 TECHNICAL ASSESSMENT ...... 139 7.6.1 Question A: Is the remedy functioning as intended by the decision documents? ...... 139 7.6.2 Question B: Are the exposure assumptions, toxicity data,c1eanup levels, and remedial action objectives used at the time of the remedy still valid? ...... 141 7.6.3 Question C: Has any other information come to light that could call into question the protectiveness of the remedy? ...... :...... 141 7.7 FT-03 ISSUES ...... :...... ·...... 141 7.8 FT-03 RECOMMENDATIONS AND FOLLOW -UP ACTIONS ...... 142 7.9 FT-03 PROTECTIVENESS STATEMENT ...... 142 7.10 FT-03 NEXT REVIEW ...... ;...... ~..... :.142 7.11 FT-03 REFERENCES ...... 142 8;0 LF-05 FIVE-YEAR STATUS REVIEW ...... · ...... ;...... 144 8.1 LF-OS DESCRIPTION AND CHRONOLOGY ...... , ...... 144 8.2 LF-OS BACKGROUND ...... , ...... 146 8.2.1 Physical Characteristics ...... 146 8.2.2 Land and Resource Use ...... ·...... ;...... 146 8.2.3 History of Contaminatiori...... 147 8.2.4 Initial Response ...... ·...... 149 8.2.S· Basis for Taking Action ...... 149 8.3 LF-OS REMEDIAL ACTIONS ...... ,...... 149 8.3.1 Remedial Action Objectives ...... ,...... IS0 8.3.2 The Selected Remedy ...... :...... ·ISI 8.3.3 Reinedy Implementation ...... lS9 8.4 LF-OS PROGRESS SINCE LAST FIVE-YEAR REVIEW ...... 160 • 8.S LF-OS FIVE-YEAR STATUS. REVIEW PROCESS ...... -...... 160 8.S.1 Community Involvement ...... 160 8.S.2 Document Review ...... ;...... 160 8.S.3 Applicable or Relevantand Appropriate Requirement Review ...... 161 8.S.4 Data Review .... , ...... 161 8.S.S Site' Inspection ...... 161 8.S.6 Interviews ...... 161 8.6 LF-OS TECHNICAL ASSESSMENT ...... 162 8.7 LF-OS ISSUES...... 162 8.8 LF-OSRECOMMENDATIONS AND FOLLOW-UP ACTIONS ...... 162 8.9 LF-OS PROTECTIVENESS STATEMENT ...... 162 8.10 LF-OS NEXT REVIEW ...... 163 '8.11 LF-OS REFERENCES ...... , ...... 163 9.0 LF-06 FIVE-YEAR STATUS REVIEW ...... 165 9.1 LF-06 DESCRIPTION AND CHRONOLOGY ...... 16S .9.2 LF-06 BACKGROUND ...... 166 9.2.1 Physical Characteristics ...... 166 9.2.2 Land and Resource Use ...... ·...... :...... 166 9.2.3 History of Contamination... , ...... 166 9.2.4 Initial Response ...... 168 9.2.S Risk Assessment Summary ...... :...... 168 9.3 REMEDIAL ACTIONS ...... 169 9.4 PROGRESS SINCE LAST FIVE-YEAR REVIEW ...... 169 • v P:IProjectslAndrews AFB EnvironmentalIFive-year reviewsl4.0 _ DeliverablesI4.1_ ReportslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

TABLE OF CONTENTS 9.5 LF-06 FIVE-YEAR STATUS REVIEW PROCESS ...... 169 • 9.5.1 Community Involvement ... ~ ...... 169 9.5.2 Document Review ...... 169 9.5.3 Site Inspection ...... ~ ...... 170 '9.5.4 Interviews ...... ;...... 170 9.6 LF-06 TECHNICAL ASSESSMENT ...... :...... 170 9.7 LF-06 ISSUES ...... 170 9.8 LF-06 RECOMMENDATIONS AND FOLLOW-UP ACTIONS ...... 171 9.9 LF-06 PROTECTIVENESS STATEMENT ...... 171 9.10 LF-06 NEXT REVIEW ...... 171 9.11 LF -06 REFERENCES ...... 171 10.0 'LF-07IBLNA FIVE-YEAR STATUS REVIEW ...... :...... •...... •...... 173 10.1 LF-07IBLNADESCRIPTION AND CHRONOLOGy...... 173 10.2 LF-07IBLNA BACKGROUND ...... 174 10.2.1 Physical Characteristics ...... 174 . 10.2.2 Land and Resource Use ...... -175 10.2.3 History of Contamination...... 176 10.2.4 Initial Response ...... ;...... 179 10.2.5 Risk Assessment Summary ...... 179 .10.3 REMEDIAL ACTIONS ...... ,...... :...... :...... 180 10.4 PROGRESS SINCE LAST FIVE-YEAR, REVIEW ...... :...... •...... 180 10.5 LF-07IBLNA FIVE-YEAR STATUS REVIEW PROCESS ...... :...... 181 10.5.1 Community 'Involvement ...... ~ ...... 181 10.5.2 Document Review ...... 181 -10.5.3 Site Inspection ...... ,...... ," ...... ·181 10.5.4 Interviews ...... 182 10.6 LF-07IBLNA TECHNICAL ASSESSMENT ...... 182 • 10.7 LF-07IBLNA ISSUES ...... 182 10.8 LF-07IBLNARECOMMENDATIONS AND FOLLOW-UP ACTIONS ...... 182 10.9 LF-07IBLNA PROTECTIVENESS STATEMENT ...... 183 10.10 LF-07IBLNA NEXT REVIEW ...... :...... ;...... 183 10.11 LF-07IBLNAREFERENCES ...... ;...... 183 11.0 SS-26 FlVE-YEAR STATUS REVIEW ...... •...... •...... 184 11.1 SS-26 DESCRIPTION AND CHRONOLOGY ...... 184 11.2 SS-26 BACKGROUND ...... •...... 185 11.2.1 Physical Characteristics ...... ,...... 185 11.2.2 Land and Resource Use ...... 185 11.2.3 History of Contamination...... , ...... 186 11.2.4 Risk Assessment Summary ...... 187 11.3 SS-26 REVIEW PROCESS ...... 187 11.3.. 1 Community Involvement ...... 187 11.3.2 Document Review ...... ;...... 188 11.3.3 Site Inspection ...... :...... 188 11.3.4 Interviews ...... 188 11.4 SS-26 TECHNICAL ASSESSMENT ...... 188 11.5 "SS-26 ISSUES ...... 189 11.6 SS-26 RECOMMENDATIONS AND FOLLOW-UP ACTIONS ...... 189 11.7 SS-26 PROTECTIVENESS STATEMENT ...... 189 • 11.8 SS-26 NEXT REVIEW ...... 189 vi

P:IProjectslAndrews AFB EnvironmentallFive·year reviewsl4.0 _DeliverablesI4.1_ ReportslFinallAndrewsAFB _5· Yr Review_Revised March 2011.doc Joint Base Andrews - First Five- Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

T ABLE OF CONTENTS 11.9 SS-26 REFERENCES ...... 189 12.0 SS-27 FIVE-YEAR STATUS REVIEW ...... 191 • 12.1 SS~27 DESCRIPTION AND CHRONOLOGY ...... 191 12.2 SS-27 BACKGROUND ...... 191 12.2.1 Physical Characteristics ...... ,...... 191 12.2.2 Land and Resource Use ...... 192 12.2.3 History of Contamination...... 192 12.2.4 Risk Assessment Summary ...... ~ ...... 193 12.3 SS-27 REVIEW PROCESS ...... 194 12.3.1 Community Involvement ...... 194 12.3.2 Document Review ...... 194 12.3.3 Site Inspection ...... , ...... 194 12.3.4 Interviews ...... ;...... 195 12.4 SS-27 TECHNICAL ASSESSMENT ...... :...... 195 12.5. SS-27 ISSUES; ...... ;...... , ... 195 12.6. SS-27 RECOMMENDATIONS AND FOLLOW-UP ACTIONS ...... 195 12.7 SS-27 PROTECTIVENESS STATEMENT ...... 195 12.8 SS-27 NEXT REVIEW ...... 196 12.9 SS-27 REFERENCES ...... :...... 196 13.0 SS-28 FIVE-YEAR STATUS REVIEW· ...... 197 ·13.1 SS-28 DESCRIPTION AND CHRONOLOGY ...... !... 197 13.2 SS-28 BACKGROUND ...... :...... 199 13.2.1 Physical Characteristics ...... , ...... 199 13.2.2 Land and Resource Use ...... : ..... ;...... 199 13.2.3 Contamination Assessment ... ~ ...... 199 • 13.2.4 Risk Summary ...... 201 13.3 SS-28 REVIEW PROCESS ...... 201 13.3.1 Community Involvement ...... 201 13.3.2 Document Review ...... 202 13.3.3 Site Inspection ...... 202 13.3.4 Interviews ...... 202 13.4 . SS-28 TECHNICAL ASSESSMENT ...... 202 13.5 SS-28 ISSUES ...... 203 13.6 SS-28 RECOMMENDATIONS AND FOLLOW-UP ACTIONS ...... 203 13.7 SS-28 PROTECTIVENESS STATEMENT ...... 203 13.8 SS-28 NEXT REVIEW ...... , ...... 203 13.9 SS-28 REFERENCES ...... 203

• vii P:IProjectslAndrews AFB EnvironmentallFive·year reviewsl4.0 _DeliverablesI4.1_ ReportslFinallAndrewsAFB _5·Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering alld Consulting, fnc. Project Number 3350092494 (Revised March 2011)

LIST OF FIGURES

Figure 1.1 Joint Base Andrews Location Map) Figure 1.2 Location of Five-Year Review Sites • Figure 2.1 . FT-04 Site Map

Figure 3.1 ST-10 Site Map Figure 3.2 ST -10 Benzene Concentrations Over Time in Groundwater Figure 3.3 ST-10 Naphthalene Concentrations Over Time in Groundwater

Figure 4.1 ST-14 Site Map

Figure 5.1 SD-23 Site Map

Figure 6.1 FT-02 Site Map

Figure 7.1 FT-03 Site Map

Figure 8.1 LF-05 Site Map

Figure 9.1 LF -06 Site Map

Figure 10.1 LF-07IBLNA Site Map

Figure 11.1 SS-26 Site Map Figure 12.1 SS-27 Site Map • Figure 13.1 SS-28 Site Map

Vlll • P:IProjectslAndrews AFB Environmental\Five-year reviewsI4.0_DeliverablesI4.I_Reports\FinallAndrewsAFB_5-Yr Review_Revised March 201l.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011) • LIST OF TABLES Table 2.1 FT-04 Groundwater Monitoring Data Summary Table 2.2 FT-04 Summary of Toxicity Value Updates

Table 3.1 ST -10 Groundwater Monitoring Requirements Table 3.2 ST-10 Groundwater Monitoring Data Summary Table 3.3 ST -10 Summary of Toxicity Value Updates

Table 4.1 ST-14 Groundwater Monitoring Data Summary Table 4.2 ST-14 Summary of Toxicity Value Updates

Table 7.1 FT-03 Groundwater Monitoring Data Summary

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LIST OF APPENDICES • Appendix A Public Notices Appendix B FT-04 ARARs, Mann-Kendall Test Results Appendix C ST-IO ARARs, Mann-Kendall Test Results Appendix D ST-14 ARARs, Mann-Kendall Test Results, Regression Plots, Molar Concentration Plots Appendix, E FT-02 ARARs Appendix F FT -03 Mann-Kendall Test Results Appendix G Responses to Regulatory Comments

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x • P:\ProjectsIAndrews AFB EnvironmentalIFive-year reviewsl4.0_ DeliverablesI4.I_ReportslFinallAndrewsAFB_5- Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Cons lilting, fnc. Project Number 3350092494 (Revised March 2011) • LIST OF ACRONYMS AND ABBREVIATIONS AFB Air Force Base AFCEE Air Force Center for Engineering and the Environment AFDW Air Force District Washington ANG ARAR applicable or relevant and appropriate requirement ASA . Air Sovereignty Alert AST aboveground storage tank

bgs below ground surface BGP Base General Plan BTAG Biological Technical Assistance Group BTEX benzene, toluene, ethylbenzene, and xylenes

CERCLA Comprehensive Environmental Response, Compensation, and Liability Act CERCLIS Comprehensive Environmental Response, Compensation; and Liability Act Information System CLP Contract Laboratory Program COC contaminant of concern ·COMAR Code of Maryland Regulations COPC contaminant of potential concern CTE central tendency exposure

DoD Department of Defense DCA dichloroethane • DCE dichloroethene DRMO Defense Reutilization and Marketing Office DRO diesel range organics

EIAP Environmental Impact Analysis Process ERP Environmental Restoration Program EPH extractable petroleum hydrocarbons ERA ecological risk assessment

FFD fuel fluorescence detector FFS focused feasibility study Fill flame ionization detector FML flexible membrane liner FS feasibility study

GCL geosynthetic clay liner GIS geographical information system GRO gasoline range organics

HHRA human health risk assessment HI hazard index HQ hazard quotient HRC® Hydrogen Release Compound • Xl P:\ProjectslAndrews AFB Environmental\Five-year reviewsl4.0_ DeliverablesI4.I_ReportsIFinallAndrewsAFB_5- Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

IC institutional control IRACR Interim Remedial Action Completion Report • LUC land use control LUCIP land use control implementation plan

MAROS Monitoring and Remediation Optimization System MCL maximum contaminant level MCLG maximum contaminant level goal MDE Maryland Department of the Environment mg/kg milligrams per kilogram MOGAS motor vehicle gasoline msl mean sea level mV milliVolt

NCP National Oil and Hazardous Substances Pollution Contingency Plan (commonly referr~d to as the National Contingency Plan) NEPA National Environmental Policy Act

ORC® Oxygen Release Compound ORP oxidation-reduction potential

PA preliminary assessment PAR polyaromatic hydrocarbons PBB Permeable Biostimulation Barrier PCB .polychlorinated biphenyl PCE tetrachloroethene (also known as perchloroethene) PGCDER Prince George's County Department of Environmental Resources • PGCHD Prince George's County Health Department PID photoionization detector PLFA phospholipid fatty acids PRB permeable reactive barrier

RAGS Risk Assessment Guidance for Superfund RAO remedial action objective RBC risk-based concentration RBSL risk-based screening level RCRA Resource Conservation and Recovery Act RI remedial investigation RME reasonable maximum exposure ROD Record of Decision

SI site investigation SSL soil screening level SVOC semivolatile organic compound SWMU solid waste management unit

TAL Target Analyte List TCE trichloroethene TCL Target Compound List· xii • P:lProjects\Andrews AFB Environmental\Five-year reviewsI4.0_DeliverablesI4.I_Reports\FinallAndrewsAFB_5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and COl/suiting, Inc. Project Number 3350092494 (Revised March 2011)

TOC total organic carbon TPH total petroleum hydrocarbons TSCA Toxic Substances Control Act

• microgr~ms /lglkg per kilogram /lglL micrograms per liter USAF U.S. States Air Force USEPA U.S. Environmental Protection Agency USFWS U.S. Fish and Wildlife Service UST underground storage tank UTL upper tolerance limit

VOC volatile organic compound VPH volatile petroleum hydrocarbons

WSSC Washington Suburban Sanitary Commission

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• Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Numb~r 3350092494 (Revised March 2011)

1.0 INTRODUCTION • Section 121 (c) of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the National Oil and Hazardous Substances Pollution Contingency Plan (NCP) at 40 CFR 300.430 require reviews of all remedial actions where hazardous substances, pollutants, or contaminants remain at a site within five years of initiating of the remedial action and no less than every five years thereafter until site conditions allow for unlimited use and unrestricted exposure. Reviews are performed to evaluate whether the selected remedial actions remain protective of human health and the environment. This five-year review report addresses twelve CERCLA Sites at Joint Base Andrews Naval Air Facility Washington (Joint Base Andrews, formerly Andrews Air Force Base), Maryland. Because the Sites are at different stages of the CERCLA process (i.e., Records of Decision [RODs] have been signed and remedial actions completed for some; RODs have been signed, but remedial actions are not fully implemented for others; and RODs have not been signed or remedial actions initiated for still others), the U.S. Environmental Protection Agency (USEPA) has requested that the Air Force complete aBase-wide five-year review .that . . evaluates the protectiveness of remedies already implemented, and provides a summary of the current status of CERCLA sites on Base that do not yet have remedies in place. Review of sites where hazardous substances, pollutants, or contaminants remain above levels that allow for unlimited use and unrestricted exposure is required by statute and is referred to as a statutory • review. The trigger for this five-year review was the signature date of the ST -10 ROD, September 28,2005.

This five-year review report was prepared by MACTEC Engineering and Consulting, Inc., in support of Delivery Order 052 of Contract FA8903-08-D-8775 under the direction of the U.S. Air Force Center for Engineering and the Environment (AFCEE). The review was completed in accordance with relevant USEPA guidance, including the Comprehensive Five-Year Review Guidance (USEPA, 2001), between October 2009 and June 2010.

1.1 PURPOSE AND SCOPE

The purpose of five-year reviews is to determine whether the remedy implemented at a site is/remains protective of human health and the environment and to evaluate the implementation and performance of the selected remedy. The review accomplishes these tasks by addressing three • major questions: P:IProjec\slAndrews AFB EnvironmentallFive-year reviewsl4.0 _ DeliverablesI4.I_ReponsIFinallAndrewsAFB_5- Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

• Is the remedy functioning as intended by the decision documents? • Are the exposure assumptions, toxicity data, cleanup levels, and remedial action objectives (RAOs) used at the time of the remedy still valid? • • Has any other information come to light that would call into question the protectiveness of the remedy?

Five-year review reports identify issues that affect protectiveness, if any, found during .the review, and make recommendations to address them.

Fjgure L 1 shows the location of Joint Base Andrews and Figure 1.2 shows the location of Sites

included in this five-year revie~. The remedial status of each Site is listed in the following table.

Review Site ·Remedial Status Type FT-04, Fire Training Area 4 ROD signed and Remedial Action Full implemented ST -10, PD-680 Spill Site ROD signed· and Remedial Action Full implemented ST -14 East Side Gas Station ROD signed and Remedial Action Full implemented SD-23, Sludge Disposal Area ROD Signed (No-Action ROD) Status FT -02, Fire Training Area 1 ROD signed, Remedial Action n·ot Status yet implemented· • FT-03, Fire Training Area 2 ROD signed, Remedial Action not Status fully implemented LF-05, Landfill 5 ROD signed, Remedial Action not Status fully implemented LF-06, Landfill 6 ROD in development Status LF-07IBLNA, Landfill 7 ROD in development Status SS-26, Hanger 15 (formerly AOC 30) No ROD yet Status SS-27, Former Dry Cleaner, Bldg 1623 No ROD yet Status SS-28, Building 1206(former!y AOC 32) No ROD yet Status

1.2 JOINT BASE ANDREWS mSTORY AND DESCRIPTION

1.2.1 History

Joint Base Andrews IS an active USAF installation located approximately five miles east of Washington, D.C., in Prince George's County, Maryland (see Figure 1.1). The Base occupies approximately 4,390 acres in north-central Maryland, and has been in operation since the 1940s. 2 • P:\ProjectslAndrews AFB EnvironmentallFive-year reviewsl4.0 _ DeliverablesI4.1_ ReportslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

Joint Base Andrews is a Superfund site and was proposed to the National Priorities List in July 1998. The site was formally added to the list May 10, 1999. It is presently undergoing • investigation and cleanup activities pursuant to CERCLA and the' NCP. The Comprehensive Environmental Response, Compensation, and Liability Act Information System (CERCLIS) ill number for the' site is MD0570024000. The USAF is the lead agency responsible for environmental cleanup at the site. A Federal Facilities Agreement is in the process of being negotiated between the USAF and USEP A.

Joint Base Andrews was originally established as the Camp Springs Army Air Field, which became operational on May 2, 1943. The name was changed to Andrews Air Force·Base (AFB) in 1947 when the USAF was established as a separate military service. In the years fqllowing World War II, Andrews APB served as headquarters for , , and the Military Air Transport Service. It was also headquarters to the Air Research and Development Command and its successor, the Air Force Systems Command, from 1950 to 1992. In a major reorganization, Headquarters Command, USAF, was disbanded on July 1, 1976, and restructured under the as the 76th Airlift Division headquartered at Andrews AFB.

• On Jan. 5, 2005 the Air Force reactivated the Air Force District of Washington (AFDW) as the single Air Force voice for planning and implementing Air Force and joint solutions within the National Capital Region. This event brought with it significant changes at Andrews. On May 12, 2006, the 89th Medical Group .at Andrews and the 11 th Medical Group, Bolling AFB, Washington, D.C., combined into the where it established its headquarters at Andrews. In June 2006, the stood up under the command of AFDW as the new host unit for Andrews AFB and its nearly 50 tenant units to inClude organizations from the Air Force Reserve, Air National Guard (ANG), , and the U.S. Navy. On 1 October 2009, the facility became Joint Base Andrews Naval Air Facility Washington, a unification of Andrews .AFB and Naval Air Facility Washington. Known as "The President's 'Wing," the continues to contribute to Joint Base Andrews' rich history as the elite wing for transporting VIPs around the world. Not only does Joint Base Andrews provide service for America's senior officials, but also kings, queens, presidents, prime ministers, popes, and local and foreign military leaders make Joint Base Andrews their fJist stop in the United States.

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Approximately 7,500 full-time military personnel were stationed, and over 9,100 civilians were employed, at Joint Base Andrews in 2008, performing a variety of missions critical to the National Capital Region. •

Joint Base Andrews consists of runways and airfield operational areas, fuel storage areas, an industrial area, and housing and recreational facilities. Remote facilities include the 1,640-acre Brandywine Receiver site, the 8-acre Brandywine Defense Reutilization and Marketing Office (DRMO), a separate NPL site, and the 863-acre Davidsonville Transmitter site (IT, 1996).

Past operational activities at Joint Base Andrews have resulted in releases of petroleum and . hazardous substances to soil, sediment, surface water, or groundwater at sites across the Base. Envirorimental investigations have been conducted .at the Base since 1985 and are being pursued under the USAF's Environmental Restoration Program (ERP) (formerly known a~ the Installation Restoration Program). The ERP was established by the Department of Defense (DoD) in 1975 to identity, investigate, and clean up former industrial disposal sites on military bases.

1.2.2 Topograpby

Joint Base Andrews is located near the westemmargin of the Atlantic Coastal Plain physiographic province (Tetra Tech, 1995) .. Coastal Plain land surfaces are typically nearly level upland plateaus • interspersed among gently rolling hills. The land surface at Joint Base Andrews is generally flat, and surface elevations in the ~icinity of the Base range from approximately 215 feet to 280 feet above mean sea level (msl) (Geo-Marine, 2001). Areas of maximum relief are the result of stream channel incision.

1.2.3 Climate

Prince George's County has a humid, temperate, serriicontinental climate. Winters are generally mild, and summers warm and moist. The period between last and first frost is generally about 185 days. Annual precipitation averages 45 inches, the majority of which is delivered during the growing season, with November and February being the driest months. The average annual wind velocity in this area is 5.8 knots (6.7 miles per hour) (EA, 1994b).

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1.2.4 Soil and Drainage • The Soil Conservation Service soil survey for Prince George's County shows general soil associations for Joint Base Andrews. The Beltsville-Leonardtown-Chillum association is the mapped soil typed in the southeast section of the Base. This association is described as having a moderately deep, well drained to poorly drained, gently sloping soil with a compact substratum or subsoil (EA, 1994b).

Surface drainage has been extensively modified at Joint Base Andrews as a result of construction. A surface water drainage divide extends generally from north to south through the Base in the vicinity of the runways. Streams in the eastern portion of Joint Base Andrews include (southeast), Cabin Branch (northeast), and Charles Branch (east). The major surface water feature is Freedom Lake, formerly called Base Lake, a shallow, eight-acre lake south of the west runway and South Perimeter Road.

1.2.5 Geology

Joint Base Andrews is located 12 miles east of the Fall Line, which represents the boundary between the Atlantic Coastal Plain and the Piedmont Physiographic Provinces. An eastward • thickening wedge of unconsolidated sediments consisting of sand, silt, and clay characterizes the Coastal Plain. These sedimentary deposits, which overlie Pre-Cambrian-age metamorphic crystalline basement rocks, are approximately 1,600 to 2,000 feet thick in the Joint Base Andrews area. Stratigraphically from highest to lowest (i.e., from (from youngest to oldest), the upper 300 feet consist of: Upland Deposits (30 feet thick); the Calvert Formation (70 to 100 feet thick); the Nanjemoy Formation (70 to 125 feet thick); the Marlboro Clay (0 to 20 feet thick); and the Aquia Formation (l00 to 140 feet thick) (Earth Tech, 2006).

The Coastal Plain formations, with the exception of the Pliocene (Upland) and Pleistocene deposits, strike northeast and dip gently to the southeast. A description of the stratigraphic units from the surface, down to and including the first major confming unit, follows.

1. The Upland Deposits consist of interbedded quartz gravel, medium to coarse sand, and minor silt and clay. The Upland Deposits form the near surface, unconfmed water-bearing unit at Joint Base Andrews. 2. The Calvert Formation is part of the Chesapeake Group in Maryland, which also includes the Choptankand St. Mary's formations. The Calvert Formation consists of greenish-gray • 5 P:\Projects\Andrews AFB EnvironmentallFive-year reviews\4.0_Deliverables\4.I_ReportslFinal\AndrewsAFB_5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering alld Consulting, Inc. Project Number 3350092494 (Revised March 2011)

silt and clay, with interbedded fmesand. Some of this material is' known to contain • diatoms, and at some places these basal Miocene deposits are Carbonaceous (Cooke, 1952). Glauconite, which likely causes the gray or green color, consists of materials reworked from the underlying Nanjemoy Formation. Small quartz pebbles of unknown origin are found near the contact with these underlying formations. Both the Calvert and Nanjemoy Formations form leaky confming units below the Upland Deposits. 3. The Nanjemoy Formation is comprised of greenish gray, micaceous, glauconitic clayey silt, with fme- to medium-grained interbedded sands. The formation strikes about N 600 E and dips 15 feet to the mile southeastward (Cooke, 1952). 4. The Marlboro FOrination was once described as the most distinctive part of the Nanjemoy Formation (Darton, 1948) before it was designated a separate formation. This formation consists of red-brown and light gray plastic clay and forms a tight confmingunit. The contact with the underlying Aquia Formation and the overlying Nanjemoy Formation is very sharp (Cooke, 1952). . 5. The Aquia Formation (Aquia Greensand) consists of dark green to gray-green, argillaceous, highly glauconitic, well sorted fme- to medium-grained sand with locally indurated shell beds. It is an important aquifer in much of southern Maryland. The Aquia Formation (Aquia Greensand) is reported to lie approximately 190 feet (Earth Tech, 2006) to as many as 230 feet (CH2M HILL, 2005) beneath the southern portion of Joint Base Andrews.

1.2.6 Groundwater

The Upland Deposits consisting of interbedded quartz gravel, medium to coarse sand, and trace amounts of silt and clay form the surficial (unconfmed) aquifer at Joint Base Andrews. Both the • Calvert and Nanjemoy Formations are· considered leaky confming units below the Upland Deposits. The Marlboro Formation forms a tight confming unit. The underlying Aquia Formation consists of greenish-black glauconic silty clays and fme sands, along with some fme-medium sand and glauconite (EA, 1994b). Groundwater is typically less than 20 feet below ground surface (bgs) at Joint Base Andrews ..

1.2.7 Current·and Anticipated Future Land Use

Joint Base Andrews is an active USAF installation. On Base activities and land use include aircraft and wheeled vehicle storage, maintenance, and servicing; office space; residential housing; and open and recreational space. Accompanied and unaccompanied residential housing is the second largest land use area on Base. Accompanied housing consists of single-family and duplex type developments, while unaccompanied housing is similar to high-density apartment use. The majority of the housing is located on the west side of the Base; however, one residential area is located east of the airfield. Outdoor recreation land use includes golf courses, ball fields, a tennis •

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court, a track, and picnic areas. The majority of the outdoor recreation facilities are concentrated • west of the airfield, in the southwest comer of the Base. The land adjacent to Joint Base Andrews includes land developed for light industrial, commercial, residential use, as well as undeveloped land. There is a business park and light industrial use area just north of the Base. Most of the area northeast of the Base is currently undeveloped. East of the Base, the land use consists of light industriallbusiness park and residential communities. Land use to the west includes residential areas with commercial shopping centers, commercial offices, and \ areas of undeveloped land. The area just south and southeast of the Base includes croplands, grasslands, wetlands, brushlands, and forest. The area just south of the Base is primarily residential and undeveloped land with some conimercial development

Joint Base Andrews is served by the Washington Suburban Sanitary Commission (WSSC) public water supply. There are no potable water supply wells at Joint Base Andrews, and there is no current use or exposure to groundwater from the surficial aquifer. Maryland's Individual Water Supply and Individual Sewerage Systems regulations contained in the Code of Maryland Regulations (COMAR) 26.03.01.05 prohibit installation of individual water .supplies where an adequate community water supply is available. A non-potable supply well was constructed near • Freedom Lake (formerly Base Lake) in fall 2002, and draws water from the'Patapsco formation at a depth of approximately 600 feet (PBS&J, 2009). The well is located on the golf course, approximately 400 feet northwest of Freedom Lake and 400 feet south of South Perimeter Road.

The Base is the home of the presidential aircraft, . It is also the airfield where foreign dignitaries arrive when visiting Washington, D.C. Overal1landuse at the Base is expected to remain the same.

The U.S. Fish and Wildlife Service (USFWS) was contacted for information regarding threatened and endangered species and sensitive habitats on or surrounding the property (Earth Tech, 2000). No federally endangered animal species or their habitats have been identified on Joint Base Andrews. There is one Federally-listed endangered plant, the sandplain gerardia (Agalinis acuta), on Joint Base Andrews, according to a 1997 Base-wide survey. Several plant species recognized by the Maryland Natural Heritage Program as "state rare" and "state highly rare" are located within the boundaries of Joint Base Andrews. Those species include tall nut-rush (Scleria trilomerata),

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Carolina foxtail, chinquapin, Curtiss' three awn grass, honeyvine, spiral pondweed, and swollen bladderwort (USAF and USEP A, 2009). • 1.3 REFERENCES

CH2M HILL, 2005. Remedial Investigation Report ST-1O, PD-680 Spill Site, Andrews Air Force. Base"Maryland, June.

Cooke (Cooke, w.e, R.O.R. Martin, and G. Meyer), 1952. Geology & Water Resources of Prince Georges County, Maryland, Bulletin 10. Maryland, Geological Survey, Baltimore, Maryland.

Dames & Moore, Inc., 1992. Groundwater Contamination Survey Andrews Air Force Base Maryland, April.

Darton, N.H., 1948. The Marlboro Clay. Econ. Geology 43:154-155.

Earth Tech, Inc., 2000. Environmental Assessment for Construction of Squadron Operations Facility and Demolition of Building 1622 at Andrews Air Force Base, Maryland, prepared forAirForce Center for Environmental Excellence, Brooks AFB, Texas, May.

Earth Tech, Inc., 2006. Final Report for the Remedial Investigation LF-05, Leroy's Lane Landfill Andrews Air Force Base, Maryland, December.

EAEngineering, Science and Technology, 1994b. Decision Document (Final) Andrews Air Force • Base, Fire T~aining Area No.4, August.

Geo-Marine, Inc., 2001. Final integrated natural resources management plan. Andrews Air Force Base, Maryland. Prepared for the Department of the Air Force, November.

IT Corporation, 1996. "Phase II Site Investigation 2132 Richmond Drive Site 18 (ST -18), Andrews Air Force Base, Maryland, prepared for Tennessee Center for Research and Development, May.

PBS&J, 2009. General 'Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland, December.

DRS, 2006. Final Basewide Conceptual Site Model, Andrew's Air Force Base, Maryland, December.

USAF and USEPA (U.S. Air Force and U.S. Environmental Protection Agency), 2009. Record of Decision, LF-05 Leroy's Lane Landfill, Andrews Air Force Base, Maryland, July.

USEPA (U.S. Environmental Protection Agency), 2001. "Comprehensive Five-Year Review Guidance", EPA 540R-OI-007, June.

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2.0 FT-04 FIVE-YEAR REVIEW • The ROD for FT -04, Fire Training Area 4, was signed on November 22, 2005. Remedial actions were initiated through a groundwater treatability study in August 2004. Because the treatability study was effective, the ROD did not select any new remedy, but allowed for additional treatment if necessary. Because hazardous substances, pollutants, or contaminants remain at the site above levels that allow for unlimited use and unrestricted exposure, this is a statutory review under CERCLA.

Information in Subsections 2.1, 2.2, and 2.3 is based primarily on material presented in the ROD (USAF, USEPA, and MDE, 2005).

2.1 FT-04 DESCRIPTION AND CHRONOLOGY

FT-04 is a former fIre training area that occupies approximately two acres near the southeast corner of the east runway at Joint Base Andrews (Figure 2.1). This location is just south of the Civil Air Patrol facility, which includes a hangar and a large asphalt area used to secure small planes while not in use. The Medivac heliCopter hangar is located immediately north of the Civil Air Patrol facility. A new propane fIre training area, located just south of FT-04, was • constructed 2000.

FT -04 was used from 1973 to 1990 asa fITe training area. When active, the site contained a 2,000-gallon aboveground storage tank (AST), a 1,000-gallon AST with inlet and outlet within a burn pit, a combustible waste-liquid distribution system, a sloped burn area 180 feet in diameter, a 390-gallon oil/water separator, and a 50-foot diameter and 6-foot deep leaching pond with a gravel bottom and concrete side walls (EA, 1994).

The combustible waste-liquid distribution system included the 1,000-gallon AST, which was used to release the liquid for burning within the bum pit. The combustible waste liquid, consisting of a mixture of chlorinated solvents and waste petroleum products, was ignited and then extinguished with an aqueous fIlm-forming foam and water. Following each exercise, excess fluids would flow by gravity across the bum area into the oil/water separator where oil was collected for off-site disposal. Residual foam and water would pass through the oil/water separator and flow to the leaching pond. Typically, liquids would seep into the ground through the gravel bottom of the leaching pond. However, the leaching pond often became plugged, and the material was • 9 P:lProjects\Andrews AFB Environmental\Five-year reviews\4.0 _ Oeliverables\4.1_ Reports\Final\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MA CTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011) discharged to the ground surface or was taken to another oiVwater separator and discharged to the sanitary sewer system (Dames & Moore, 1992). As a result of the activities at FT-04, chlorinated solvents commingled with petroleum hydrocarbons in the aquifer. The releases of regulated • substances are believed to have occurred both at the ftre training pit and at the AST north of the pit.

FT-04 is an ERP site that" is in the CERCLA process at Joint Base Andrews. A chronology of remedial studies, investigations, and reports atFT-04 is presented below.

• 1985: Phase I IRP Records Search (ES, 1985) • 1985: Phase n, Stage 1 IRP Investigation (URS, 2005a) • 1989: Phase n, Stage 2 IRP Investigation (USGS, 1989) • 1992: Groundwater Contamination Survey (Dames & Moore, 1992) • 1992: Interim Removal Action (IT, 1993) • 1993: Human Health and Environmental Risk Assessment (EA, 1993) • 1994: Focused Feasibility Study {EA, 1994). • 1996 to 2000: Pilot Treatability Study (EA, 2002) • 1999: Baseline Groundwater Sampling (EA, 1999) • 2003 to 2004: CERCLA Remedial Investigation (URS, 2005a) • 2004: CERCLA Basewide Background Study (CH2M HILL, 2004) • • 2005: CERCLA Focused Feasibility Study(URS, 2005b) • 2004 to 2005: HRC Groundwater Treatability Study • 2005: Record of Decision (USAF, USEPA, and MDE, 2005) • 2007: Injection ofHRC® at Injection Area 3

2.2 FT-04 BACKGROUND

2.2.1 Physical Characteristics

The land surface at FT -04, like most of Joint Base Andrews, is generally flat. There are no natural surface-water features at the FT-04 site. Surface water runoff from FT-04 drains to Piscataway Creek, located approximately 0.7 miles to the southwest, which is the closest surface-water body (EA, 1994b).

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The surficial materials at FT -04 are Upland Deposits consisting of unconsolidated tan and orange sand with silt and gravel, with intervals of silty clay. The estimated thickness of surficial material • at FT -04 is 20 to 30 feet. The Calvert FOrlnation clay unit was encountered at 27 feet and at 21 feet in two FT-04 monitoring wells, MW93FT04-04 and MW93FT04-03, respectively (EA, 1994b).

During the remedial investigations (RI), groundwater was encountered at FT -04 at approximately 6 to B'feet bgs in the Upland Deposits. In the vicinity ofFT-04, groundwater flows northwest at an estimated average seepage rate of 142 feet per year (URS, 2005a).

2.2.2 Land and Resource Use

FT-04 is located near the southeast corner of the east runway at Joint Base Andrews, just south of the Civil Air Patrol facility, which includes a hangar and a large asphalt area used to secure small planes while not in use. A new fire training area is located south of the site. An Air Sovereignty Alert (ASA) facility, consisting of an aircraft hangar and worker and pilot facilities has been constructed over a portion of the site, Pilots who are on alert reportedly live at the facility for the duration of their shifts. FT-04 is within an area currently designated for airfield use, aircraft • operations and maintenance, and open space. Future land use is designated as airfield use and aircraft operations and maintenance (PBS&J, 2009). The site is within the airfield/flight line security zone, and access is limited to personnel with airfield/flight line security badges.

There are no potable water supply wells located at Joint Base Andrews, including FT-04, and there is no current use or exposure to groundwater. Groundwater at FT -04 is not expected to be used for such purposes in the future. Joint Base Andrews is currently served by public water supplied by WSSC,and, according to COMAR 26.03.01.05, wells cannot be installed in areas where public water infrastructure is available.

No areas of archaeological or historical importance have been identified at FT -04.

2.2.3 History of Contamination

2.2.3.1 Groundwater

Twenty-two monitoring well groundwater samples (20 pnmary and 2 d~plicate) and seven temporary well point groundwater samples (six primary and one duplicate) were collected at FT-04 • 11 P:IProjectslAndrews AFB EnvironmentallFive-year reviewsl4.0_ DeliverablesI4.I_ReportsIFinallAndrewsAFB_5- Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting,. Inc. Project Number 3350092494 (Revised March 2011) during two rounds of sampling for the RI. Groundwater samples were analyzed for a combination of target compound list (TCL) volatile organic compounds (VOCs), TCL semivol~tile organic compounds (SVOCs), TCL pesticides, target analyte list (TAL) metals, dioxins/furans, natural • attenuation parameters, and selected field parameters. The primary contaminants of potential concern (COPCs) for groundwater were determined ·based on exceedances of USEPA drinking water Maximum Contaminant Levels (MCLs) and USEPA Region III risk-based concentrations (RBCs). Base-wide background groundwater concentrations were available for selected metals, methane, and cresol and were also used for comparison. Carbon tetrachloride and benzene are the most prevalent COPCs in groundwater at the site.

The RI found a plume containing carbon tetrachloride and benzene extending north-northwest from an area north of the former bum pit and west of Building 2487. Elevated concentrations of manganese and arsenic were also encountered within the plume. The most substantial carbon tetrachloride and benzene contamination was present in the vicinity of the asphalt parking area. The highest detected concentrations of carbon tetrachloride 'and benzene were 282 micrograms per liter (~glL) and 191 ~g/L in samples collected from monitoring well MW0302-FT04. The most prevalent contaminants observed in soil gas samples were carbon tetrachloride and benzene, which are contaminants resulting from activities conducted at FT-04 (URS, 2003). • Manganese exceeded its Base-wide background concentration of 159 ~glL (CH2M HILL, 2004) in

14 monitoring well samples and exceeded the secondary MCL of 50 ~glL in 17 of18 monitoring well samples collected from the FT -04 area. The occurrence of elevated concentrations of dissolved manganese is sporadic throughout FT-04 groundwater. Arsenic was detected above the laboratory minimum detection level (4.6 ~g/L) in two out of 18 groundwater samples collected within the FT-04 area. One of these samples contained an arsenic concentration of 15.9 ~glL, which was above the USEP A primary drinking water standard of 10 ~glL. This sample was collected from well MW8502-FT04, which is located in the former bum pit. Thee1evated concentrations of manganese and arsenic in the groundwater are likely a consequence of biodegradation of the organic contaminants in the groundwater at FT -04. Manganese and arsenic occur naturally in the aquifer's soil matrix. As a result of the releases of organic contaminants into the groundwater and surrounding soil, a reduced oxidation-reduction potential (ORP) geochemical condition was produced in the aquifer as microbes in the subsurface soil consumed oxygen in the process of degrading the organic contaminants. This geochemical condition in the aquifer can cause the release of arsenic (Kelly et al., 2005) and other metals from the surrounding soil into the •

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groundwater. The effect is temporal and can be reversed when the aquifer returns to its natural • aerobic conditions. Biodegradation of the organic contaminants in groundwater appears to have limited the extent of the plume (URS, 2005a). Over the 15 years or more that have elapsed since the original environmental releases occurred at the site, the groundwater plume containing carbon tetrachloride and benzene has remamed near the fIre training area arid has not migrated off-site.

(' 2.2.3.2 Soil

During the RI for FT-04, 15 surface soil samples (zero to one foot bgs) were collected from around the former FT-04 burn pit, the east taxiway, and the Aero-Club asphalt area. In addition, a total of 19 subsurface soil samples were collected from varying depths. Soil samples were analyzed in the laboratory for a combination of TCL VOCs, TCL SVOCs, TCL pesticides and polychlorinated biphenyls (PCBs), TAL metals, and moisture content. Subsurface soil samples were also analyzed . for dioxins/furans, total organic carbon (TOC), and pH. Detected analytes'in surface soil samples above RBCs included benzo(a)pyrene,arsenic, and dieldrin. Benzo(a)pyrene and dieldrin were each detected above USEPA Region III residential soil RBCs in one surface soil sample adjacent to the former bum pit (dieldrin) and east of the asphalt area (benzo(a)pyrene). Arsenic was detected • . above both industrial and residential soil RBCs in all surface soil samples analyzed for TAL metals. Analytes detected in subsurface soil samples above RBCs included arsenic; 1,2,3,4,6,7,8­ heptachlorodibenzo-p-dioxin; and octachlorodibenzofuran. Arsenic was detected above residential soil RBCs 'in samples collected from all subsurface soil sample locations where samples were analyzed for metals, and also above industrial soil RBCs in samples collected from two locations adjacent to the former burn pit: one location east of the asphalt area, and one location east of Building 2487: The dioxin (l,2,3,4,6,7,8-heptachlorodibenzo-:p-dioxin) and the furan (octachlorodibenzofuran) were both detected above industrial and residential soil RBCs in samples collected from two depths at subsurface soil sample locations within the former bum pit.

2.2.4 Initial Response

2.2.4.1 Interim Removal Action

In 1992, the USAF. initiated an interim removal action to remove sources that potentially could . contribute to site contamination and to recover light non-aqueous phase liquid product from • 13 P:\ProjectslAndrews AFB EnvironmentalIFive-year reviewsI4.0_DeliverablesI4.1_ ReportslFinallAndrewsAFB _ 5-Yr Review ~Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011) existing wells within the former bum pit. Between August and December 1992, the oiVwater separator, leaching pond, and visually impacted soil were removed, and the burn pit was filled with clean cover material. Specific activities performed during the interim removal action are listed • below.'

• Burn pit soil and leaching pond were dewatered and disposed off-site. • Leaching pond sludge was stabilized and disposed off-site. • The combustible waste-liquid distribution system and concrete from the pond and the oiVwater separator were demolished and removed. • Visibly contaminated soil was excavated down to approximately four to six feet bgs in the burn pit and six feet bgs in the leaching pond. • Two ASTs (a 2,000-gallon iank and a 1,000-gallon tank) were removed.

The seven-foot -deep concrete sidewalls of the leachate collection pond were in excellent condition prior to demolition (IT, 1993). During the interini. removal action, 429 tons of soil, concrete, and debris were disposed of off-site. It rained during the interim removal action, and contaminated absorbent material used to dry the waste was included in the disposal. In addition, 79,394 gallons of surface and pond water also were disposed off-site. The site was restored with a 4~inch layer of imported topsoil (355.5 tons) that was spread over the fire pit area, the oiVwater separator area, and the leachate collection pond area. The area was then hydro seeded. A passive free-product • recovery system was operated from August 1992 to August 1994 and recovered approximately 12 gallons of free-phase product.

2.2.4.2 Free Phase Removal

Between 1999 and 2000 a vacuum-enhanced recovery system was used to recover free phase petroleum at FT ~04 as part of a pilot test'with a planned one~year duration. A· comparison of the results of post-pilot test soil sampling with the soil sampling results from 1993 did not conclusively show a reduction in VOCconcentrations in source area soils, and the system was determined to be ineffective.

2.2.4.3 HRC® Treatability Study

Based on the groundwater data produced during the RI, a treatability study was undertaken as part of the RI to evaluate enhancement of naturally occurring biological activity by injecting an organic •

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substrate into the groundwater to induce biodegradation of organic contaminants (URS, 2005a). The treatability study also was undertaken to determine if enhanced in-situ biodegradation could • expedite site remediation to accommodate the construction schedule of the ASA facility.

Review of the data produced during the RI, including evaluation of concentration trends,indicated that benzene concentrations at the FT-04 site were decreasing faster than carbon tetrachloride concentrations, suggesting that naturally-occurring attenuation of benzene was proceeding more quickly than the naturally-occurring attenuation of carbon tetrachloride. Therefore, the treatability study was designed to fIrst test treatment of carbon tetrachloride, which was present in higher concentrations and presented greater health risks than benzene, followed by treatment of benzene, if necessary.

The scope of the treatability study included baseline groundwater sampling, injection of Hydrogen Release Compound (HRC®) substrate, and effectiveness monitoring at a frequency of approximately 3,6, 12, and 18 months post-injection. The HRC® was injected in August 2004 at 134 locations at a dose of 5 pounds per linear foot. A total of6,570 pounds of HRC®and 4,380 pounds of HRC® Primer was added to the aquifer at Injection Areas 1 and 2. Post-injection • monitoring was conducted in December 2004 and March 2005. The treatability study concluded that the carbon tetrachloride plume had decreased signifIcantly in size and concentration. Post-injection monitoring (December 05 and March 2005) showed reduction in carbon tetrachloride concentrations from an average of 131 IlglL and maximum of 274 IlglL to less than the cleanup criterion of 5 IlglL in six monitoring wells (MW0302-FT04, MW0304-FT04, MW0402-FT04, MW0403-FT04, MW0404-FT04, MW0405-FT04) downgradient of Injection Areas 1 and 2.

The results also showed that the extent of benzene contamination decreased during the treatability study. In August 2004 fIve of six monitoring wells had benzene exceeding the cleanup criterion of 5 IlglL (ranging from 47 to 178 Ilg/L with average of 95 Ilg/L). By August 2005, three of the fIve wells had benzene concentrations less than 5 IlglL, and the othertwo showed reductions of 56 and 75 percent. The maximum benzene concentration between these two wells was 78 11 gIL.

Review of the June 2006 and September 2006 Post-ROD data showed increasing concentrations of both benzene and carbon tetrachloride at MW8805-FT04, located upgradient of the Injection Areas • 15 P:IProjec\SIAndrews AFB EnvironmentallFive-year reviewsl4.0 _ DeliverablesI4.I_Repons\FinallAndrewsAFB_5- Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

1 and 2, in the vicinity of the fonner 1,000-gallon AST (MACTEC, 2007a). To prevent the recontamination of downgradient areas with migrating benzene and carbon tetrachloride, a second round of HRC® injection (Injection Area 3) was completed in September 2007 to treat the source • in the vicinity of the 1,000-gallon AST (MACTEC, 2009).

2.2.5 Basis for Taking Action

The human health risk assessment (HHRA) of the RI detennined that, ifFT-04 groundwater, based on its beneficial use designation, were to be used as a potable water source, carbon tetrachloride, benzene, manganese, and arsenic could result in potential unacceptable risks (URS, 2005a). All v four contaminants of concern (COCs) were present above their respective MCLs; The focused feasibility study (FFS) concluded that carbon tetrachloride, benzene, manganese, and arsenic represented potential risks requiring remediation to restore beneficial uses of the aquifer, but that· exposure to vapor emanating from groundwater at FT -04 no longer poses an unacceptable health risk.

The HHRA indicated that the hazard indices (HIs) and excess lifetime cancer risks from exposure to all COPCs in soil at FT -04 do not present an unacceptable risk for future residents, commercial workers, or construction workers exposed to surface and subsurface soil at FT-04. Therefore, exposure to site contaminants present in surface and subsurface soil is not expected to result in • unacceptable health effects to potential future receptors. The site also does not pose an unacceptable ecologicahisk. Therefore, no further action was required for soil at FT -04 ..

The ROD concluded that response action was necessary to protect public health or welfare from actual or threatened releases of pollutants or contaminants in groundwater.

2.3 FT -04 REMEDIAL ACTIONS

The ROD for FT -04 was signed in November 2005 documenting the selected remedy for cleanup ofgroundwater associated with known releases at the Site (USAF, USEPA, and MDE, 2005).

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2.3.1 Remedial Action Objectives • Based on an evaluation of site conditions, an understanding of the contaminants, the results of the risk assessments, and an analysis of applicable or relevant and appropriate requirements (ARARs), the ROD identified the following RAOs for FT -04:

• Protect potential future human receptors from exposure to contaminated groundwater and unacceptable risk associated with the vapor emanating from the groundwater plume; • Restrict the use of groundwater until the groundwater is cleaned up; and • Monitor the progress of the groundwater cleanup of carbon tetrachloride, benzene, manganese, and arsenic.

COCs and cleanup concentrations are listed in the following table.

Contaminants of Concern and Cleanup Criteria at FT -04 Cleanup Criterion Contaminant of Concern (llglL) Basis for Selection Arsenic 10 MCL Benzene 5 MCL · Carbon tetrachloride 5 MCL • Manganese 159 Background 2.3.2 . The Selected Remedy

The selected remedy at FT-04 was FFS Alternative 2: Monitoring of HRC® Treatment and

Institutional Controls. This IS a continuation of the HRC® injection treatability study performed at ) Injection Areas 1 and 2 as part of the RI in .2004. Injection was performed at Injection Area 3 in September 2007. The remedy addresses groundwater contamination and potential future exposure to contaminated groundwater. The major components of the selected remedy consist of the following:

• Perform groundwater monitoring to determine concentration trends of COCs through statistical evaluation and conduct five-year reviews; • hnplement and maintain institutional controls (ICs) in the form of land and groundwater use restrictions until the cleanup criteria for carbOn tetrachloride, benzene, manganese, and arsenic are achieved; , • On the basis of groundwater monitoring data, initiate further in-situ treatment of the groundwater as indicated by ROD Figure 2-8 if concentrations of COCs do not continue to decline sufficiently to attain cleanup criteria within a reasonable time. • 17 P:IProjects\Andrews AFB EnvironmentalIFive-year reviewsl4.0 _DeliverablesI4.1_ ReportslFinal\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

2.3.2.1 Groundwater Monitoring, Statistical Trend Evaluations, and Potential Further Treatment

As described in the ROD, the groundwater monitoring program included in this alternative is to be • used to, determine the effects of the treatability study. Groundwater monitoring is to be conducted semiannually for five years, and then annually until cleanup criteria for carbon tetrachloride, benzene, manganese, and arsenic are achieved. The ROD identified the monitoring network as three existing monitoring wells (MW8801-FT041, MW9302-FT04,and MW0401-FT04) and six . new/proposed monitoring wells, whose locations were tentatively identified on ROD Figure 2-7, to replace monitoring wells being abandoned because of ASA construction.

The objective of the groundwater monitoring is to assess the ongomg effect of groundwater treatment initiated during the treatability study and to determine the degradation rate and mass reduction of the COCs. The data also are also to be used to evaluate whether the concentrations of carbon tetrachloride, benzene, manganese, and arsenic ate decreasing at a .rate that would meet , their cleanup criteria within 10 years after signature of the ROD. Analytical parameters identified in the ROD are listed below.

• VOCs (includes benzene and carbon tetrachloride) • Metals (includes arsenic and manganese) • • Nitrate • Sulfate • Methane, ethane, ethene • Phospholipid fatty acids (PLF A)

• TOC • Field parameters: temperature, conductivity, pH, ORP, and dissolved oxygen

The measurements of nitrate, sulfate, methane, ethane, ethene, and field parameters were included to assess the aquifer's capacity for degradation of the organic COCs at FT-04. The PLFA results will indicate the presence and condition of the microbes within the subsurface. The monitoring

program can be refmed as new data ~re analyzed. For cost estimating purposes, the ROD estimated the time required to achieve the cleanup criteria as 10 years. The remedial timeframe can be refmed as more data are generated as part of the groundwater monitoring. Additional monitoring may be required to verify achievement of cleanup criteria with certainty. 18 • P:\Projects\Andrews AFB Environmental\Five-year reviewsl4.0 _ DeliverablesI4.1_ Reports\FinallAndrewsAFB _ 5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

Additionally, as part of the CERCLA five-year review process, the concentrations of all COCs and their statistical trends are to be reviewed. If the concentration trends do not indicate a statistically • significant decrease in COC concentrations to cleanup criteria within a reasonable timeframe (based on cost effectiveness analysis), more treatment may be applied. The cost-effectiveness analysis is to compare the cost to continue groundwater monitoring until the predicted timeframe for cleanup criteria is met versus the cost for enhancing biodegradation through further treatment to achieve cleanup criteria within a shorter timeframe. Thus, the cost for additional treatment followed by limited groundwater monitoring may be less than longer-term monitoring that would otherwise be necessary in the absence of treatment. ROD Figure 2-8, Exit Strategy for Groundwater Treatment at FT -04, presents a logic diagram to be followed.

2.3.2.2 Institutional Controls

Because the selected remedy for FT -04 leaves contaminants in place at levels that do not allow unlimited use and unrestricted exposure, the remedy includes ICs to ensure that the contaminants do not pose an unacceptable rlsk to human health or the environment during the time until cleanup criteria are attained. The general areas for which ICs are to be implemented are illustrated on • Figure 2.1. The IC objectives are as follows:

. 1. Prohibit the use of groUndwater potentially impacted by FT-04, other than for environmental monitoring or testing, until cleanup criteria are met for, benzene, carbon tetrachloride, manganese, and arsenic; 2. Ensure that activities on Base do not damage or interfere with the monitoring wells or the ability to undertake required environmental monitoring or testing; 3. Ensure any proposed changes in land use are consistent with ICs;

4. Ensure any proposed construction activities at FT~04 are evaluated with regard to risks posed by compounds at the. site, and the potential for construction to exacerbate site conditions. The nature of the site construction may require additional health and safety controls or engineering controls. 5. Prohibit contactwith groundwater at FT-04 by Joint Base Andrews maintenance workers. 6. In the event that groundwater impacted by FT -04 is withdrawn during construction . activities, ensure that it is appropriately stored, managed, and disposed.

The USAF is responsible for implementing, monitoring, maintaining, reporting on, and enforcing the ICs at FT-04: Under Alternative 2, the site is to be designated as a "restricted use" area in the Base Geographical Information System (GIS). This designation prohibits activities such as residential development or use of groundwater. Additionally, groundwater use is currently • 19 P:lProjectslAndrews AFB Environmental\Five-year reviewsI4.0_DeliverablesI4.1_ Reports\FinallAndrewsAFB _ 5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting. Inc. Project Number 3350092494 (Revised March 2011) restricted, as documented in the Base General Plan (BGP), and procedures are in place to limit contact with groundwater through ,the issuance of dig permits and other protective measures (PBS&J, 2009). Records of the groundwater contamination are to be kept in the Base • GIS/environmental database. The restricted-use designation will remain in place until groundwater monitoring indicates that the cleanup criteria have been achieved at FT-04.

Any activity that is inconsistent with the IC objectives or use restrictions, or any other action that may interfere with the effectiveness of the ICs will be addressed by the USAF as soon as practicable, but in no case will the process be initiated later than 10 days after the USAF becomes aware of the breach. The USAF will notify USEPA and Maryland Department of the Environment (MDE) regarding how the USAF has addressed or will address the breach within 10 days of sending USEPA and MDE notification of the breach. The ICs can be modified as new data are analyzed; however, the USAF will not modify or terminate land use controls (LUCs), implementation actions, or modify land use without approval by USEPA and the MDE. The USAF will seek prior concurrence before any anticipated action that may disrupt the effectiveness of the LUCs or any action that may alter or negate the need for LUCs. The ROD identified the following ICs for application at FT-04: • .• Notification provided to USEPA and MDE at least six months prior to any transfer or sale of FT-04 so that USEPA and MDE can be involved in discussions to ensure that appropriate provisions are included in the transfer terms or conveyarice documents to maintain effective ICs.If it is not possible for the facility to notify USEPA and MDE at least six months prior to any transfer or sale, then the facility will notify USEP A and MDE as soon as possible, but no later than 60 days prior to the transfer or sale of any property subject to ICs. In addition to the land transfer notice and discussion provisions above, the USAF further agrees to provide USEPA and MDE with similar notice, within the same time frames,as tofederal~to federal transfer of property. The USAF shall provide a copy of executed deed or transfer assembly to USEPA and MDE. • Review and approval of any changes in land use, including construction of new facilities or additions to existing facilities at FT-04 by the Joint Base Andrews Facility Review Board, which interacts with the Community Planner using the BGP as a guide to land use Issues; • Inclusion of the restrictions at FT-04 on the BGP. All ERP sites and restrictions at Joint Base Andrews are identified in the BGP. Any proposed activity or construction on an ERP site requires an "ERP Waiver to Construct" memorandum, approved and signed by USAF Headquarters Air Mobility Command; • . Review of proposed construction activities to ensure protection from risks posed by contaminants at FT-04, such as the ASA facility constructed at FT-04, by Joint Base • Andrews Environmental Flight through the following processes: Environmental Impact 20

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Analysis Process (EIAP), National Environmental Policy Act (NEPA) Design Reviews of Proposed Construction, review of routine Work Orders that involve alterations to facilities, and review of Dig Permits; • • Posting signs at the site identifying FT -04 as a CERCLA site. The signs will summarize the nature of contamination at the site and will state that no construction or excavation activities and no groundwater use, or withdrawal, is· pennitted within the area without written authorization by the USAF. Contact information for ERP project manager will also be included on the signs. • Restriction of access. Authorized personnel only are pennitted to access the site; and • Continued prohibition of potable use of groundwater. Potable use of groundwater is prohibited at FT-04. Environmental personnel review of Work Orders and Dig Permits will also ensure that potable groundwater wells will not be installed at FT-04.

The ICs are to remain in place until the concentration of contaminants at the site allows for unrestricted use and exposure. Monitoring of the environmental use restrictions and controls will be conducted annually by Joint Base Andrews. The monitoring results will be included in a separate report or as a section of another environniental report, if appropriate, and provided to USEPA and MDE for informational purposes only. The annual monitoring reports will be used in preparation of the five-year review to evaluate the effectiveness of the remedy. The annual monitoring report will evaluate the status of the ICs and how any IC deficiencies or inconsistent uses have been addressed. Joint Base Andrews is to notify USEPA and MDE 45 days in advance • of any proposed land use changes that are ~consistent with LUC objectives or the selected remedy.

2.3.3 Remedy Implementation

Quarterly groundwater samples were collected at FT -04 from August 2004 through March 2005, and have been collected semiannually since then. Analytical parameters have included those required by the ROD plus chloride, SVOCs, and PCBs. . The September 2009 groundwater sampling event represented the last seini-annual sampling event required by the ROD, before transitioning to annual sampling.

Construction activities for the ASA facility have resulted in damage to, or abandonment of, several FT-04 monitoring wells. These wells have been replaced, however, and several additional wells , . installed as required by the ROD. The locations ofnewIreplacement wells was in part controlled by the newly constructed ASA facilities. Seventeen monitoring wells were available for sampling

in S~ptember 2009.

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2.3.4 System Operations/Operation and Maintenance The selected remedy for FT-04 does not require operation' and maintenance. • 2.4 FT-04 PROGRESS SINCE FmST FIVE-YEAR REVIEW

This is the fIrst fIve-year review for FT-04.

2.5 FT-04 FJVE-YEAR REVIEW PROCESS

2.5.1 Community Involvement

The USAF has maintained a public involvement and information program for the ERP since 1990 . and maintains an Administrative Record as required by CERCLA. The Administrative Record is maintained at the Environmental Flight, 3466 North Carolina A venue, Joint Base Andrews. For the convenience of the public, a copy of the Administrative Record is maintained in an Information Repository located at:

Prince George's County Memorial Library.:Surratts-Clinton Branch 9400 Piscataway Road Clinton, MD 20735 • Community involvement activities for thisfIve~year review consisted of publishing a notice in two local newspapers announcing the USAF's intent to perform the fIve-year review and providing information where and how the public could obtain additional information. The notice appeared in the Prince George's County Gazette on December 3, 2009, and in the Capital Flyer on December 18, 2009. A copy of the notice is provided in Appendix A.

2.5.2 Document Review

The fIve-year review included review of relevant documents including the following:

.• Final Remedial In:vestigation Report, Site FT-04 - Fire Training Area 4 (URS, 2005a) • Final Focused Feasibility Study, Site FT-04, Andrews Air Force Base, Maryland (URS, 2005b) • Final Record ofDecision, FT04, Fire Training Area 4 (USAF, USEPA, and MDE, 2005) • Andrews Air Force Base General Plan, Land Use Control Implementation Plan, FT-04 • (USAF,2007) 22

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• 30-Month and 36-Month Post-ROD Groundwater Monitoring Report ERP Site FT-04 (MACTEC, 2008a) • Report of September 2007 HRC Injection and 30-Month and 36-Month Post-ROD • Groundwater Monitoring Report ERP Site FT -04 (MACTEC, 2008b) • 42- and 48-Month Post-ROD Groundwater Monitoring Report, ERP Site FT-04 (Fire Training Area 4) (MACTEC, 2009a) • Report of Annual LUC Monitoring, Andrews Air Force Base, Maryland, October2007- December 2008 (MACTEC, 2009b) • General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland (PBS&J,2009)

2.5.3 Applicable or Relevant and Appropriate Requirement Review

The ARARs presented in Appendix B of the ROD are reprinted and appended in Appendix B of this report. These standards and regulations were current at the signing of the ROD and, as part of this five-year site review, have been reviewed for changes that could affect protectiveness. None of the ARARs listed in Appendix B have had changes since signing of the ROD that affect the .protectiveness of the implemented remedial action .

In addition, a search was performed for any newly promulgated standards which could affect • protectiveness at the site. No new ARARs were identified that would affect the protectiveness of the remedy.

Changes to ARARs and TBCs that pertain to risk assessment are discussed in Subsection 2.6.2.

2.5.4 Data Review

This five-year review Included review of groundwater analytical data from FT -04 monitoring wells for the period from August 2004 through September 2009 (Table 2.1), with a focus on benzene, carbon tetrachloride, arsenic, and manganese; the COCs identified for FT -04. These were the most recent data available at the time this report was drafted. Five (MW0302-FT04, MW0304-FT04, MW0402-FT04, MW0403-FT04, MW0405-FT04) of the six monitoring wells originally used to assess the performance of the HRC® treatability test remain in place and serviceable and provide the best data for assessing concentration trends. Seven replacement wells (MW0701-FT04, MW0702-FT04, MW0703-FT04, MW0704-FT04, MW0705-FT04, MW0706-FT04, and • MW0901-FT04) have been installed to replace monitoring wells no longer in place or serviceable, .

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Benzene. Review of monitoring data indicates that benzene concentrations in FT -04 monitoring wells have been less than the cleanup criterion of 5 IlglL since March 2007 with the exception of MW0302-FT04 and MW0405--FT04. At MW0302-FT04, benzene concentrations have ranged widely, both increasing and decreasiiig, over the period extending from August 2004 through September 2009 as illustrated in the following table.

Benzene Concentrations vs. Time at MW0302-FT04 Date Concentration, J.l.glL Date Concentration, J.l.glL Aug 2004 100 Mar 30, 2007 10 Dec 2004 1.6 Oct 24,.2007 29.2 Mar 2005 1.2 May 2, 200S 195 Aug IS, 2005 47 Dec 17, 200S 13 Feb 2006 5.5 Mar 10,2009 410 Jun 16, 2006 23 Sep 17,2009 S.3 Sep 12, 2006 0.6S During this time period benzene concentrations at MW0302-FT04 went from 1OOllglL to a low of • 0.6S IlglL and then a high of 410 11 gIL. Most recently, in September 2009, the benzene concentration was S.3 11 gIL. The decrease in concentrations between August 2004 and September 2006 corresponds to decreases in carbon tetrachloride concentrations and maybe a result of degradation processes. Review of historical data tables does not show corresponding increases in other VOCs or SVOCs. The reasons for the increases in May 200S and March 2009 are not known.

At MW0405-FT04, the greatest benzene concentration was 2.01 IlglL during the period from 2004 to May 200S.Concentrations spiked to 17 IlglL in March 2009, but decreased to 5.4llglL in September 2009. If these latest results are representative of recent conditions, MW0405-FT04 appears very close to attaining the benzene cleanup criterion of 5 IlglL.

The Mann-Kendall Test was applied to datasets from 10 monitoring wells with 4 or more data points using AFCEE's Monitoring and Remediation Optimization System (MARaS) (Appendix B). The Mann-Kendall Test is a non-parametric test for trend that is often used in evaluation of •

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environmental data. The test calculates the Mann-Kendall statistic S which if positive indicates an increasing trend and if negative indicates a decreasing trend. The greater the absolute value of the • S statistic, the greater the confidence in the trend. As implemented by the MAROS software, the test identifies six possibilities: increasing, probably increasing, stable, probably decreasing, decreasing, and no trend, depending on the value of the Mann-Kendall statistic and the coefficient of variation of the data.

The Mann-Kendall Test identified only MW0302-FT04 as having an increasing or probable increasing trend for benzene. While the statistical analysis for MW0302-FT04 indicates a probable increasing trend when all available data are considered, the upward trend is driven by the unusually high values for MW0302-FT04 in May 2008 (195 !J.glL) and March 2009 (410 !J.glL). Based on the September 2009 data (8.3 !J.glL), MW0302-FT04 appears close to attainillg the benzene cleanup criterion of 5 !J.glL. The Mann-Kendall Test iridicated "no trend" at MW0405-FT04.

Based on these analyses, "it appears that good progress is being made at attaining the benzene cleanup criterion of 5 !J.g/L. If recent degradation rates continue, then attainment of benzene

concentrations in MW0302-FT04 and MW0405-FT04 is likely within the originally estimated 10~ • year time frame. Carbon Tetrachloride. Review of the analytical data indicates that the carbon tetrachloride

cleanup criterion of 5 !J.glL has not been exceeded since April 2004 in FT~04 monitoring wells with the exception of MW8805-FT04 and MW9304-FT04 located in an area now covered by concrete apron at the ASA facility. MW8805-FT04, located upgradient of Injection Areas 1 and 2, but downgradient of Injection Area 3 showed a marked increase in carbon tetrachloride concentrations betWeen August 2004 and March' 2005, but an approximate 90 percent reduction (930 to 95 !J.glL) between September 2006 and March 2007 after injection of HRC® at Injection Area 3. A March 2007 sample from monitoring well MW9304-FT04, located adjacent to MW8805-FT04, had a carbon tetrachloride concentration of 17 !J.glL. These two wells have not been available for sampling since March 2007. Monitoring well MW0901-FT-04 was installed as a replacement for MW8805-FT04 and MW9304-FT04. Carbon tetrachloride was not detected in the June and September 2009 samples from MW0901-FT04.

The Mann-Kendall Test identified only MW9303-FT04 as having an increasing or probable • increasing trend for carbon tetrachloride. Review of the data in Table 2.1 shows that carbon

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Based on recent data, it appears that the carbon tetrachloride cleanup criterion of 5 IlglL has been attained.

Arsenic. Review of monitoring data indicates only sporadic historical exceedance of the 10 IlglL cleanup criterion for arsenic in FT-04 monitoring wells. Arsenic was reported at 11 and 15 IlglL in MW0402-FT04 in August 2005 and September 2006, respectively. Five subsequent samples from this well in' 2006, 2007, 2008, and 2009 were all less than 10 IlglL. No other exceedances of arsenic were noted.

Based on these data, it appears that the cleanup criterion of10 IlglL for arsenic is being attained.

Manganese. Review of analytical data indicates widespread exceedances, both historical and current, of the manganese cleanup criterion of 159 Ilg/L which was based on its Base-wide background concentration. Data from ten wells (MW0302-FT04, MW0304-FT04, MW0401-FT04, • MW0402-FT04, MW0403~FT04, MW0405-FT04, MW0501-FT04, MW8801-FT04, MW9302- FT04, and MW9303-FT04) covering the period between April 2004 and September 2009 were subjected to the Mann-Kendall Test as applied by the MAROS software with the result that two wells, MW0304-FT04 and MW8801-FT04, showed decreasing or possible decreasing trends (Appendix B). It should be noted that the manganese concentrations at MW8801-FT04 were less than the cleanup criterion. Three wells, MW0302-FT04, MW0402-FT04, MW9303-FT04, showed increasing or possible increasing trends. These three wells are within or downgradient of Injection Areas 1 and 2, and high concentrations of manganese as a result of low ORP and reductive dissolution are not unexpected. Samples from the other five monitoring wells showed stable or no­ trend conditions. Further review of the statistical output for these five 'wells shows that the Mann­ Kendall statistic S for three of them (MW0401-FT04, MW403-FT04,' and MW0501-FT04) was negative, indicative of a decreasing trend; however, the MAROS software' attached a low confidence level to the statistic for those wells and described them as exhibiting stable or no-trend conditions. Data from MW0501-FT04, similar to MW8801-FT04, do not exceed the cleanup criterion. 26 • P:\ProjectslAndrews AFB Environmental\Five-year reviews\4.0_ Deliverables\4.1_ Repons\FinallAndrewsAFB _5-Yr Review_Revised March 201l.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting. Inc. Project Number 3350092494 (Revised March 2011)

Recently installed wells MW0701-FT04, MW0702-FT04, MW0703-FT04, MW0704-FT04, and MW0706-FT04 were sampled for the fIrst time in September 2009, and showed manganese • concentrations ranging from 250 to 420 IlglL, with all fIve wells exceeding the manganese cleanup criterion of 159 IlglL. MW0705-FT04, also sampled for the fIrst time, did not exceed the cleanup criterion. MW090 1"FT04 exceeded the cleanup criterion in a June 2009 baseline sample (200 vs. 159 Ilg/L), but not in September 2009.

The presence of manganese is attributed to naturally occurring minerals and not to discharges from human activities on Base. Based on available data, it is evident that substantial and widespread reductions in manganese concentrations will be required to attain the cleanup criterion of 159 11 gIL. These reductions are expected after degradation of petroleum-related contaminants and HRC® substrate is complete and groundwater returns to aerobic conditions. A supplemental round of HRC® injection at Injection Area 3, upgradient of many site monitoring wells, in September 2007 (more than two years after injections at Injection Area 1 and 2) may extend the amount of time needed for groundwater to return to aerobic conditions and for reduction in manganese concentrations. Additionaltime and monitoring data are required to assess whether the2015goal will be met. It may be desirable to consider a risk-based value in lieu of Base-wide background concentration as the manganese cleanup criteria. The USEP A Regional Screening Level for • manganese in groundwater is 880 Ilg/L, which is a risk-based value (hazard quotient (HQ) = 1).

2.5.5 Site Inspection

A LUC inspection was performed at FT-04 in January 2009 as part of a comprehensive LUC inspection at Joint Base Andrews CERCLA sites with RODs (MACTEC, 2009b). In addition, the site was viewed from outside the airfIeld/flight line security fence on October 21, 2009. This later inspection confIrmed site land use assumptions.

2.5.6 Interviews

No interviews were conducted with community members in regard to FT-04. A public notice was published in two area newspapers in December 2009, indicating that the review process was underway and providing contact information for questions or comments. No inquiries from the general public were received. Input on the review process was obtained from representatives of the USEPA,MDE, and Prince George's County through their participation in the Tier 1 partnering team and by their review of preliminary drafts of this document. • 27 P:IProjectslAndrews AFB EnvironmentallFive-year reviewsl4,O _ DeliverablesI4.1_ ReportslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

2.6 FT':'04 TECHNICAL ASSESSMENT

2;6.1 Question A: Is the remedy functioning as intended by the decision ,documents? •

Yes, the remedy is functioning as intended by the ROD, as discqssed further below.

Implementation of Institutional Controls and Other Measures. The Joint Base Andrews Environmental Flight developed a LUC Implementation Plan (LUCIP) for the FT-04 site in March 2007 (USAF, 2007), and provided it to the Joint Base Andrews Community Planner so that LUCIP for the site could be incorporated into the BGP, the Base's comprehensive land use planning document. The LUCIP presents specific requirements for the establishment, implementation, and maintenance of LUCs at FT -04.

Joint Base Andrews has posted signs at FT-04 to indicate that groundwater at the site presents a potential hazard and that construction, excavation, and groundwater use are prohibited (MACTEC, 2009).

Electronic map layers showing the locations of restricted areas associated with ERP sites have been • posted on the official Joint Base Andrews GIS (Andrews AFB Geo-Base) to assist all organizations with project planning and design tasks (MACTEC, 2009b).

A Waiver~to-Construct is required for all proposed construction on an ERP site (AFI32-1021). A Waiver-to-Construct means the proposed construction has been evaluated with respect to site activity and environmental risks proposed by the construction and ultimate use of the facility. The BGP contains a listing of ERP sites as well as a map showing their locations (PBS&J, 2009). The BGB identifies FT -04 as an area where LUCs have been established.

During construction of the ASA facility, several monitoringvwells were abandoned/destroyed. This was anticipated in the ROD which described the post-ROD monitoring well network as 3 existing wells (MW0401-FT04, MW9302-FT04, MW8801-FT04) and 6 replacement monitoring wells whose tentative location, based on the anticipated ASA facility footprint, was shown on ROD Figure 2-7. The USAF installed six replacement monitoring wells (MW0701-FT04 through MW0706-FT04) in 2007 and one (MW0901-FT04) in 2009. The result was a monitoring well layout consistent with the tentative layout in the ROD figure. Because fewer wells were destroyed •

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than anticipated in the construction ofthe ASA facility, an extensive array of monitoring wells is • available for sampling. In addition, groundwater is prohibited from being used for potable purposes anywhere on Base (PBS&J, 2009), and COMAR 26.03.01.05 prohibits installation of new water supply wells.

Annual LUC monitoring has been completed twice since the LUCIP was put in place in 2007. The most recent report, covering calendar year 2008, concluded that all required LUCs have been implemented for FT -04 (MACTEC, 2009b. The 2008 report did not identify inconsistent uses or LUC deficiencies, or activities that could interfere with the effectiveness of the land use restrictions and controls. The report for 2009 was being prepared at the time this five-year review was being drafted .

.Remedial Action Perforinance. Based on available data, the remedial action has achieved the cleanup criteria for carbon tetrachloride and arsenic, and·is expected to meet the cleanup criterion for benzene in the near future (in advance of the 10-year goal). Manganese concentrations, however, remain greater than the cleanup criterion across most of the site. Based on the fact that a possible increasing, or absence of decreasing trend, is observed iIi several wells, it is unclear • whether the manganese cleanup criterion will be attained within the 10-years of ROD signature .goal. Several of the subject wells are in, or downgradient of, the Injection Areas I and 2. Elevated concentrations of naturally-occurring manganese are not unexpected in groundwater that has been treated with HRC®. Additional time is needed for groundwater to become aerobic again thus enabling manganese to precipitate out of solution, and it is not clear that the cleanup criterion will be attained within the '1 O-year time frame.

System Operations/Operation and Maintenance. The selected remedy at FT -04 does not include remedial systems that require operation and maintenance. Ground water monitoring is being performed as required by the ROD.

Some optimization of the groundwater sampling program maybe possible. The September 2009 groundwater sampling included 17 monitoring wells, a considerably greater number than the 9 discussed in the ROD. The conceptual site model alid monitoring data be reviewed to determine if any monitoring wells can be eliminated from the sampling program. Because several of these

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wells are new to the monitoring program and have only been sampled once, at least one additional sampling event (i.e., fall 2010) is recommended, however. • SVOC analysis is not required by the ROD, but was included in the analytical suite for September 2009 samples as well as several other recent sampling rounds. SVOC results are typically less .than the reporting limit, although a couple of sporadic exceedances of regulatory criteria have occurred. SVOCshave not been identified as COCs at FT -04, and do not appear to be risk drivers. Consideration should be given to droppingSVOC analysis from the FT-04 analytical suite.

Cost of System Operations/Operation and Maintenance. Estimated and actual costs for remedial action operation (RA-O) are shown in the following table. As is shown, actual costs are close to estimated costs and do not suggest operational issues.

FT-04 Annual System Operations, Monitoring; and Maintenance Costs Calendar Year Year Estimated Costl CurrentlActual Cost Description 1 2005 $55,488 $63,000 RA-O 2 2006 $55,488 $70,000 RA-O 3 2007 . $55,488 $40,000 RA-O 4 2008 $55,488 $51,000 RA-O 5 2009 $67,488 $62,000 RA-O Notes: The initial injection of HRC® substrate was in August 2004. Operations, monitoring and maintenance costs have been assumed to begin in 2005. • I Estimated costs from FT-04 Record of Decision Table 2~3

Expected Progress Towards Meeting RAOs~ See Remedial Action Performance above.

2;6.2 Question B: Are the exposure assumptions, toxicity data, cleanup levels, and RAOs used at the time of the remedy still valid?

Yes, the exposure assumptions, toxicity data, cleanup levels and RAOs remain valid.

Changes in Standards and To Be Considered Values. This five-year review did not identify ARARs that have been promulgated since the ROD was signed.

Changes in Exposure Pathways. FT -04 compnses several small hangars and paved aircraft parking areas, including a recently constructed ASA facility. FT -04 is within an area currently designated for airfield use, aircraft operations and maintenance, and open space. Future land use is designated as airfield use and aircraft operations and maintenance (i.e., industriaVcommercial use) for the foreseeable future. 30 • P:\ProjectslAndrews AFB Environmental\Five-year reviews\4.0 _Deliverables\4.1_ Reports\FinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

The scenario of ASA pilots sleeping at the ASA facility was not evaluated in the risk assessment of • the RI. Given the proximity of the building to the plume of VOC contamination in groundwater, ongoing evaluation of the potential completeness of the vapor intrusion exposure pathway is I warranted.USEPAguidance for evaluating the vapor intrusion exposure pathway (OSWER Draft Guidance for Evaluating the Vapor Intrusion to Indoor Air Pathway from Groundwater and Soils [2002]) indicates that the vapor intrusion pathway would be considered potentially complete if VOCs are detected in groundwater that is within 100 feet of an occupied building, at concentrations in excess of the vapor intrusion screening values published in the guidance document.

To evaluate whether this exposure pathway could potentially be significant, current (mostrecent) concentrations of VOCs in groundwater from monitoring wells that are nearest to the ASA building were compared to vapor intrusion screening values published by USEPA (OSWER Draft Guidance for Evaluating the Vapor Intrusion to Indoor Air Pathway from Groundwater and Soils [2002]). No VOCs were detected in wells MW0901-FT04 and MW0402-FT04 at concentrations in excess of the vapor intrusion screening values. Benzene was detected in MW0302-FT04 at a concentration (8.3 )lg/L based on September 2009 sampling) slightly above the vapor intrusion screening level (5 )lg/L, which is based on the USEPA MCL). However, monitoring well MW­ • 0302 is located approximately 100 feet from the building, in a direction down gradient from the building. Well MW0901-FT04, where no VOCs were detected at concentrations greater than the vapor intrusion screening values, is located adjacent to the building and upgradient of MW0302- FT04. The conceptual site model would suggest that VOCs in groundwater are migrating away from the building and that concentrations which could represent a potential vapor intrusion concern are attenuating. Additionally, the ASA facility building remains unoccupied as of the preparation of this report. Collectively, the information suggests that VOCs in groundwater do not pose a vapor intrusion concern for the ASA building at FT-04. The USEP A and its toxicologist have reviewed the current conditions at FT -04 and agree with the conclusion that the site does not pose an unacceptable vapor intrusion. risk.

Groundwater at FT -04 is not used as a potable water source at this time and is not expected to be used for such purposes in the future. Joint Base Andrews is currently served by public water supplied by WSSC, and, according to COMAR 26.03.01.05, potable water wells cannot be installed in areas where public water infrastructure is available. No changes to the use of • groundwater on Base, or supply of public water to the Base, are anticipated. Nonetheless,

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groundwater is considered a natural resource under the Maryland Anti-Degradation Policy (COMAR 26.08.02.04), and must be maintained as a potential source of drinking water. Consequently, the RAOs stipulated in the ROD, to restore shallow groundwater to expected • beneficial uses to the extent practicable, are unchanged by land uses or exposure pathways.

Changes in Risk Assessment Methodology, Toxicity, and Other Contaminant Characteristics. The baseline risk assessment for FT-04 identified COPCs for exposures to surface soil; vapors and particulates of surface soil origin; and groundwater and vapors of groundwater origin. Eight COPCs were noted for surface soil and surface soil suspended )as vapors or particulates. None of the COPCs were identified as COCs requiring remediation.

Eighteen COPCs were noted fo,rgroundwater, four of which (benzene, carbon tetrachloride, manganese, and arsenic) were identified as COCs requiring remediation. Ten COPCs were ·identified for vapors of groundwater origin, one of which (carbon tetrachloride) was identified as a COC. However, following HRC® injection, a risk assessment was performed during the second

post~treatment sampling event in March 2005. The characterization combined maximum detected concentrations with conservative assumptions in a US EPA-approved model for vapor intrusion. The model determined that the non-cancer HI associated with inhalation of carbon tetrachloride for · the future commercial worker was reduced from 37.5 to 0.57, and the cancer risk was reduced from 5 • 4.2xl0-4 to 1.44xlO- • Therefore, exposure to vapors of groundwater origin was no longei considered to pose an unacceptable health risk. The copes that were not. identified' as COCs requiring remediation were established as such because they did not contribute significantly to .risks.

The toxicity values for the COPCs and COCs were reviewed to determine if any changes (updates) to toxicity values could change the COCs identified as chemicals requiring remediation.

Of the COPCs identified in FT -04 soil and groundwater, toxicity values selected in accordance with the USEP A policy on human health toxicity values in Superfund risk assessments (USEP A, ·2003) have been updated as shown in Table 2.2.

The updated toxicity value for carbon tetrachloride would further lower the future commercial worker non-cancer HI. Therefore, the conclusions of the risk assessment or selection of COCs requiring remediation remain unchanged. 32 • P:\Projects\Andrews AFB Environmental\Five-year reviewsl4.0 _ DeliverablesI4.I_Reports\Final\AndrewsAFB_5- Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

Implications on Cleanup Levels. The groundwater cleanup levels for the COCs were based on • the USEPA MCLs for benzene (5 /lglL), carbon t~trachloride (5 /lglL) and arsenic (10 /lglL); and the Base-wide background concentration for mangariese (159 /lglL). None of the identified changes in exposure pathways, risk assessment methodology, or toxicity values would change the cleanup levels or call into question the protectiveness of the remedy.

(

2.6.3 QuestionC: Has any other information come to light that could call into question the protectiveness of the remedy?

No. No other information has come to light that calls into question the protectiveness of the ( . . remedy. The potential for a completed vapor intrusion pathway has been considered, but based on observed groundwater contaminant concentrations and direction of groundwater flow, vapor intrusion does not pose an unacceptable risk. No indoor air sainpling was conducted during the RI, because no structures were located on the site at the time the RI was completed.

2~6.4 Technical Assessment Summary

• The use of the ASA facility as temporary sleeping quarters by pilots represents a change in site conditions that may affect the protectiveness of the remedy.

It may take several years for anaerobic groundwater conditions resulting from injection of HRC® at Injection Area 3 to flush through the site, thereby allowing aerobic conditions conducive to precipitation of manganese to return. It is unclear whether aerobic conditions will return in time to meet the goal. of attaining the manganese cleanup criterion by 2015; however, the HRC® injection at Injection Area 3 was not anticipated or considered in setting the 2015 cleanup goal. Although injection of ORC or similar product might accelerate the return of aerobic conditions and reduction of manganese concentrations, allowing anaerobic groundwater to flush naturally should be considered. This will allow full advantage to be taken of anaerobic conditions for degradation of carbon tetrachloride and for groundwater to return to aerobic conditions naturally.

Based on the data reviewed,the remedy is otherwise functioning as intended by the ROD. There have been no changes to toxicity factors for COCs or changes to risk assessment methodology that would change the protectiveness of the remedy. There is no other information that calls into question the short-term protectiveness of the remedy. • 33 P:\Projects\Andrews AFB EnvironmentalIFive-year reviews\4.0 _DeJiverables\4.1_ ReportslFinal\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, lllc. Project Number 3350092494 (Revised March 2011)

2.7 FT~04 ISSUES

The following table summarizes the issues identified or Site FT-04 during this five-year review. •

Affects Protectiveness Issues (yIN) Current Future The scenario of ASA pilots sleeping at the ASA facility was not evaluated in the risk assessment of the RI. However, a review of the site conditions indicates that the vap~r intrusion pathway is not likely to pose an N N unacceptable risk to the eventual occupants of the ASA facility. USEPA and its toxicologist are in agreement with this conclusion.

2.8 FT~04 RECOMMENDATIONS AND FOLLOW-UP ACTIONS

Follow-up actions are only identified for issues that affect current and/or future protectiveness. For Site FT-04, no issues have been identified that require follow-up actions.

2.9 FT-04 PROTECTIVENESS STATEMENT

The selected remedy for FT-04 is expected to be protective of human health and the environment • upon completion,an~, in the interim, exposure pathways that could result in unacceptable risks are being controlled.

2.10 FT-04 NEXT REVIEW

FT-04 is a statutory site that requires ongoing five-year reviews as long .as contaminants remain on site above levels that allow for unlimited use and unrestricted exposure. The next review will be performed within five years of the completion of this five-year review report. The completion date is the date of the signature shown on the signature cover attached to the front of this report.

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2.11 FT-04 REFERENCES

CH2M HILL, 2004. Final· Basewide Background Study Report, Andrews Air Force Base, • Maryland, March. Dames & Moore, Inc., 1992. Groundwater Contamination Survey Andrews Air Force Base . . Maryland, April.

EA Engineering, Science and Technology, 1993. Human and Environmental Health Risk Assessment, Andrews Air Force Base, Fire Training Area No.4, July.

EA Engineering, Science and Technology, 1994a. Final Focused Feasibility Study, Andrews Air Force Base, Fire Training Area No.4, April.

EA Engineering, Science and Technology, 1994b. Decision Document (Final) Andrews Air Force Base, Fire Training Area No.4, August.

EA Engineering, Science and Technology, 1999. Results of December 1998 Baseline Ground­ Water Sampling Event, Fire Training Area No.4, Andrews Air Force Base, February.

EA Engineering, Science and Technology, 2002. Final Pilot Treatability Study Closure Report, Fire Training Area No.4, Andrews Air Force Base, April.

MACTEC, 2007a. Interim Remedial Action Construction Report, ERP Site FT-04 (Fire Training Area 4), 18- and 24-Month Post-ROD Groundwater Monitoring Events, Andrews Air Force, Base, Camp Springs, Prince George's County, Maryland, July.

MACTEC, 2008a. 30-Month and 36-Month Post-ROD Groundwater Monitoring Report ERP Site FT-04 (Fire Training Area 4) Andrews Air Force Base Camp Springs, Prince George's County, Maryland, March.

MACTEC, 2008b. Report of September 2007 HRC Injection and 30-Month and 36-Month Post­ ROD Groundwater Monitoring Report ERP Site FT-04 (Fire Training Area 4) Andrews Air Force Base Camp Springs, Prince George's County, Maryland, June.

MACTEC,2009a. 42- and 48-Month Post-ROD Groundwater Monitoring Report, ERP Site FT-04 (Fire Training Area 4), Andrews Air Force Base, Camp-Springs, Prince George's County, Maryland, February.

MACTEC, 2009b. Report of Annual Land Use Control Monitoring, Andrews Air Force Base, Maryland, October 2007 - December 2008, February.

PBS&J, 2009. General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland, December. .

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URS, 2005a. Final Remedial Investigation Report, Site FT-04 - Fire Training Area 4, Andrews • Air Force Base, Maryland, July.

URS, 2005b. Final Focused Feasibility Study, Site FT-04, Andrews Air Force Base, Maryland, October.

USAF (U.S. Air Force), 2007. Andrews Air Force Base General Plan, Land Use Control Implementation Plan, FT -04, Andrews Air Force Base, Maryland, March.

USAF, USEPA, and MDE (U.S. Air Force, U.S. Environmental Protection Agency-Region III, and Maryland Department of the Environment), 2005. Final Record of Decision, FT04, Fire Training Area 4, Andrews Air Force Base, Maryland, November.

USAF (U.S. Air Force), 2006. Report of Annual Land Use Control Monitoring, Andrews Air Force Base, Maryland, September 2005 - December 2006.

USEPA (U.S. Environmental Protection Agency), 2003. Human Health Toxicity Values ill Superfund Risk Assessments, OSWER No. 9285.7-53, December.

USGS (U.S. Geological Survey), 1989. Installation Restoration Program Remedial Investigation / Feasibility Study (RIlFS),. Stage I Draft Report, April. •

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3.0 ST-I0 FIVE-YEAR REVIEW •• The ROD for ST-lO was signed on September 28,2005. Remedial actions were initiated as an in­ situ bioremediation treatability study in October 2004. Because hazardous substances, pollutants, or contaminants remain at the site above levels that allow for unlimited use and unrestricted exposure, this is a statutory review under CERCLA.

Information in Subsections 3.1, 3.2, and 3.3 is based primarily on material presented in the ROD (USAF, USEPA, and MDE, 2005).

3.1 ST-I0 DESCRIPTION AND CHRONOLOGY

ST -10, also referred to as the PD-680 Spill Site, is the former location of an underground storage tank (UST) that reportedly leaked 5,000gaUons of the petroleum-based solvent PD-680 (Dames & , Moore 1992). The Site occupies approximately one-half acre. ST-lOis located within the flight line security zone on the northwest side of Joint Base Andrews (see Figure 1.2) and is bounded by 1st Street to the west and Wash Rack Pad 1770 to the east (Figure 3.1). Between 1990 and 1993, six USTs were removed from ST-10; one 25,000-gallon UST remains at the site and stores propylene glycol for aircraft deicing purposes ..The six removed USTs ranged in size from 2,500 to • 25;000 gallons and contained products such as PD-680, waste oil, glycol, detergent, jet fuel (JP-4), and other solvents.

PD..,680 is a petroleum distillate, also known as dry cleaning safety solvent, petroleum solvent, Stoddard solvent, and varnoline, that is typically used at DoD facilities for dry cleaning, general cleaning, and degreasing activities. Over time, the PD-680 UST at ST-10 is believed to have leaked, resulting in releases to soil and groundwater. In the early 1970s, a fiberglass UST was removed because it was leaking PD-680. A new fiberglass UST was installed in its place. Unfortunately, the new UST was improperly installed, and as a result, when this UST was filled with PD-680, it also leaked. This latter leak was estimated to be approximately 5,000 gallons. None of the PD-680 solvent was recovered. The second replacement tank was installed in about 1975 and removed in April 1991 (Dames & Moore, 1992).

No inventory records were maintained about the specific materials stored in the waste oil tanks. Data indicate the waste oil tanks at the site leaked into soil and groundwater. A 10,000-gallon waste oil UST at Building 1773 was identified in a 1988 Resource Conservation and Recovery Act • 37 P:\Projects\Andrews AFB Environmentill\F'ive-year reviews\4.0_ Deliverables\4.1_ Reports\Final\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year, Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number '3350092494 (Revised March 2011)

(RCRA) Facility Assessment report by the MDE to have failed a leak test and to have been scheduled for removal (MDE, 1988). A 1991 Tank Removal/Abandonment field report from MOE indicates this waste oil UST had several stress cra<;:ks at the time of its removal, and that the UST •• had leaked into the soil and groundwater (MOE, 1991).

Total petroleum hydrocarbons (TPH) have been detected in soil and groundwater throughout the site in the vicinity of both the PD-680 tank and the waste oil USTs removed from the site. As a result, it is difficult to identify the source of the TPH, and both the PD-680 tank and the waste oil USTs·are probably commingled sources of the TPH present at the site.

Although releases ofpetroleum distillate (i.e., PD-680) are normally regulated under the MOE Oil Control Program, the fact that documented reports indicate waste oil from USTs leaked to subsurface soil and groundwater and commingled with other releases at the site has resulted in managing the entire site cleanup under CERCLA. The TPH and chlorinated compounds (trichloroethene [TCE] and vinyl chloride) detected in the vicinity of the waste oil tanks substantiate the release of CERCLA-regulated contaminants.

ST-IO is an ERP site that is in the CERCLA process at Joint Base Andrews. A chronology of • remedial studies, investigations, and reports at FT-04 is presented below.

• 1973/1974: Replacement ofleaking PD-680 UST (Dames & Moore, 1992) • 1975: Second replacement ofleaking PD-680 UST (Dames & Moore, 1992) • 1988: RCRAPhase 2 Facility Assessment (MDE, 1988) •. 1991: Removal ofPD-680 UST (Dames & Moore, 1992) • 1992: Groundwater Contamination Survey (Dames & Moore, 1992) • 2001 to 2002: Annual Monitoring Well Sampling (IT, 2001, 2002) • 2004:CERCLA Basewide Background Study (CH2M HILL, 2004a) • 2004 to 2005: In-Situ Bioremediation Treatability Study (CH2M HILL, 2004b) • 2004 to 2005: Remedial Investigation (CH2M HILL, 2005a) • 2005: Focused Feasibility Study (CH2M HILL, 2005b) • 2005: Record of Decision (USAF, 2005)

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3.2 ST-IO BACKGROUND • 3.2.1 Physical Characteristics . The topography. of ST-lOis relatively flat with an elevation at approximately 259 feet above msl. ST-lOis mostly paved, and the majority of rainwater deposited in this area is removed via surface water and/or storm water flow through storm water pipes. There are no surface water bodies on or - near ST-10. Surface water and storm water is directed north toward Henson Creek, where it ultimately is conveyed and discharged into the Potomac River (CH2M HILL, 2005a).

The surficial material at ST -10 generally consists of interbedded layers of light brownish-yellow to gray fme silty clays; hard, dense layers of gray clayey silts; and lenses of fme yellowish silty sand. The top of the confming unit is approximately 33 feet bgs in the center of the site, near the suspected former location of the PD-680 UST. The upper 16 feet of surficial material at ST-10 generally consists of interbedded layers of light brown to gray silts and clays which are underlain by light brown coarse sand and gravel to a depth of 32 feet bgs. The sand and gravel.layers throughout the site vary in depth and are not continuous. • 3.2.2 Land and Resource Use The Joint Base Andrews BGP defmes the land use at ST-IO as "aircraft operations and maintenance" currently and in the foreseeable future (PBS&J, 2009). ST-IO is presently used for storage of deicing fluids and .equipment. Adjacent land includes paved aprons and runways, airplane hangars, and office space (CH2M HILL, 2005a). The site is within the airfield/flight line security zone, access is limited to personnel with airfield/flight line security badges. Joint Base Andrews is planning to construct a cargo-handling building at ST -10. The building is currently (spring 2010) in the design phase, and a construction waiver has been signed in accordance with institutional controls required by the ROD (see Subsection 3.32.2).

There are no potable water supply wells located at Joint Base Andrews, including ST-IO, and there is no current use or exposure to groundwater. Groundwater at ST-lO is not expected to be used for such purposes in the future. Joint Base Andrews is currently served by public water supplied by the WSSC, and, according to COMAR 26.03.01.05, wells cannot be installed in areas where public water infrastructure is available.

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No areas of archaeological or historical importance have been identified at ST-10.

3.2.3 Hi_story of Contamination • 3.2.3.1 Soil

No surface soil samples were collected during the RI because the USTs at the site were buried; and releases to the environment occurred in the subsurface soil.

During the RI, soil was initially screened for lithology and TPH using a fuel fluorescence detector (FFD). These results were used to identify locations most likely to contain TPH contamination. Samples were collected for laboratory analysis to confirm FFD results and evaluate whether other compounds were also present in the subsurface. A total of 12 subsurface soil samples were collected and analyzed based on the FFD screening results. An additional six subsurface soil

samples were collected and ~alyzed when the new groundwater monitoring wells were installed.

FFD field screenmg data collected in April 2003 suggested that TPH subsurface soil impacts (concentrations of TPH above 10 milligrams per kilogram [mg/kg]) are located between 9 and 16 feet bgs, in the vicinity of the PD-680 tank. TPH-diesel range organics (DRO) were present more frequently and generally at higher concentrations than TPH-gasoline range organics (GRO). Two • phases of subsurface soil sampling were conducted following the FFD screening in April 2003 and September/November 2003. The highest detected concentrations of TPH-DRO were in the vicinity of the PD-680 tank location, with a maxlmum value of 140 mg/kg. Three other samples in the vicinity of the waste oil USTs contained TPH-DRO at concentrations greater than 10 mg/kg. These locations and depths were resampled approximately 6 months later for extractable petroleum hydrocarbons (EPH) and volatile petroleum hydrocarbons (VPH) (subsets ofTPH compounds), but no petroleum hydrocarbons were detected in the later samples. This variation may be caused· by the differing sensitivity of the analytical methods or could potentially indicate natural degradation. Because TPH consists of a range of possible petroleum compounds, no residential RBC has been developed for TPH in soil (USAF, 2005).

Benzene, toluene, ethylbenzene, and xylene (BTEX) were detected in four of 18 subsurface soil samples. The highest concentrations of ethyl benzene (26 micrograms per kilogram [Ilg/kg]) and ·total xylenes (56 Ilg/kg), and the only detection of benzene in soil (0.77 Ilg/kg), were detected in the same sample as the highest TPH-DRO concentration, in the vicinity of the PD-680 tank 40 • P:\Projects\Andrews AFB EnvironmentallFive-year reviews\4.0_Deliverables\4.I_ReportslFinal\AndrewsAFB_5-Yr Review_Revised March 201l.doc Joint Base Andrews'- First Five- Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number.3350092494 (Revised March 2011)

location. These concentrations were less than the then current USEPA Region III residential soil • RBCs of7,800, 16,000, and 12 mglkg, respectively. Metals were detected in subsurface soil samples at concentrations near or below background concentrations, except as fcillows:

• Sodium, thallium, and iron were detected in at least one sample at a concentration exceeding the background upper tolerance limit (UTL).

• Sodium was detected in nin~ samples at concentrations ranging from 56.4 to 128 mglkg, exceeding the background UTL of 43.4 mglkg. . • Thallium and iron each exceeded their background UTLs (0.332 mglkg and 27,800 mglkg) in only one sample at concentrations of 1.9 mglkg and 35,800 mglkg, respectively. • Selenium was detected in one subsurface soil sample at a concentration of 0.74 mgikg. No background UTL was developed for selenium for comparison with concentrations detected on site.

PCBs were not detected in any of the subsurface' soil samples at the site.

3.2.3.2 Groundwater

• During the RI, four existing and seven newly-installed monitoring wells were sanipled, and 20

direct~push groundwater samples were collected from 18 locations.

The majority of metals in groundwater at the site were found to be below background concentrations except for mercury and silver. Mercury and silver were detected in site groundwater but were not present in Base-wide backgroi.md groundwater samples. Mercury was detected during one of the two sampling rounds during the RI in on-site monitoring well MW02- STl 0 at an estimated concentration of 0.675 Ilg/L, which is below the method detection limit and \ below the MCL of 2·llglL. Silver was detected in one of the two sampling rounds during the RI in site background well MWOI-STlO (3.68 IlglL) and on-site at one location (MW04-STlO) at a concentration of 5.62 IlglL. No MCL has been established for silver Silver and mercury were only detected during the 2001 round of sampling. These compounds were not detected during the 2002 round of sampling.

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Arsenic concentrations have been detected in groundwater at the site in the Central Plume above the MCL (10 IlglL) and above background concentrations of arsenic (which ranged from non­ . . detect to 1.16 Ilg/L) at the Base. The RI concluded that the source Of arsenic in groundwater at ST­ • 10 is uncertain, but not likely a direct release from the tanks. The arsenic is more likely an indirect consequence of the PD-680 and waste oil commingled releases which resulted in TPH contamination in groundwater. Arsenic is naturally occurring in soil. As a result of the TPH releases from the USTs into the groundwater and surrounding soil, microbial growth in the soil and groundwater was promoted. The microbes consume the oxygen in the subsurface, creating an anaerobic (reduced oxygen) and reduced ORP geochemical condition which causes release of arsenic from the surrounding soil into the groundwater (Kelly et al., 2005). The presence of methane (which is a byproduct of TPH degradation) in groundwater at ST-IO is also indicative reducing geochemical conditions arid is strongly correlated to elevated concentrations of arsenic in groundwater at the site.

During the RI, TPH-GRO were detected in six monitoring wells at concentrations ranging from 18 to 230 IlglL, and TPH-DRO were detected in each of the eleven monitoring wells at concentrations ranging from 210 to 1,000 IlglL. The maximum concentration of TPH-DRO was detected in MW02-ST10 in the Central Plume, coincident with arsenic. • The VOCs with the highest detected concentrations at the site are benzene, toluene, ethylbenzene, andlor xylenes, with benzene appearing most frequently and at the highest concentrations. Naphthalene has also been detected frequentiy at the site. Prior to the treatability study, the highest concentrations of these constituents were detected in monitoring well MW10-STl 0, adjacerit to the PD-680 UST and in the same area where the highest soil impacts were identified (i.e., the Northern Plume). The highest concentrations of benzene and naphthalene in this monitoring well prior to the treatability study were 51 and 257 IlglL, respectively, which are above the MCL for benzene (5 IlglL) and the risk-based criterion calculated for naphthalene (18 Ilg/L). The concentrations of benzene and naphthaJene in well MW 1O-STl 0 after the most recent post-treatability-study sampling event were below the cleanup criteria at 3.6 and 8.9 IlglL, respectively. TCE and vinyl chloride have also been detected at the site, generally at concentrations below their respective MCLs (5 Ilg/L and 2 IlglL).

Very slow groundwater flow at the site, as a result ·of low hydraulic gradients, limits migration of dissolved compounds away from the site. Over the 30 years which have elapsed since the original •

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environmental releases occurred at the site, the groundwater plumes containing arsenic, benzene, and naphthalene remain closely located to the original UST locations and have not migrated off­ • site. After implementation of the treatability study, the sizes Of the groundwater plumes have been greatly reduced to point locations around specific~wells.

3.2.4 Initial Response

Initial responses at ST -10 include the following:

• 1973/1974: Replacement ofleaking PD-680 UST (Dames & Moore, 1992)

• 1975: Second r~placement ofleaking PD-680 UST (Dames & Moore, 1992) • 1988: RCRA Phase 2 Facility Assessment (MDE, 1988) • 1991: Removal ofPD-680 UST (Dames & Moore, 1992) • In-Situ Bioremediation Treatability Study (CH2M HILL, 2004b)

3.2.5 Basis for Taking Action

The risk assessments determined that there are no calculated risks or hazards that exceed USEP A target levels for the future adult resident, lifetime resident, industrial worker, or construction • worker exposed to subsurface soil. The future child resident is the only evaluated receptor that had a total reasonable maximum exposure (RME) HI greater than the USEP A target level of one. Exposure to iron in subsurface soil is the only COPC that contributed a HQ greater than one to the

HI (iron HQ = 1.6). When the total HI is segregated by target organ/critical effect, the only effects that result in cumulative HIs greater than one are those associated with iron exposure (gastrointestinal, blood, and liver). Iron is an essential human nutrient, and because the nutritional rt

The risk assessment determined that, in the potential event that groundwater at ST -10 was to be used as drinking water in the future, based on its beneficial use designation, arsenic, naphthalene, vinyl chloride, and TPH are present at concentrations in groundwater which could result in • 43 P:lProjectslAndrews AFB EnvironmentallFive-year reviewsl4.0 _ DeliverablesI4.1_ReponslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc loint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting. Inc. Project Number 3350092494 (Revised March 2011)

potential unacceptable risks. Of these constituents, the FFS concluded that arsenic, benzene, and .' naphthalene represented potential risks that require remediation. The ROD concluded that vinyl chloride and TPH do not require remediation. •

The ROD concluded that response action was necessary to protect public health or welfare from actual or threatened releases of pollutants or contaminants from ST-I0 in groundwater.

3.3ST~lO REMEDIAL ACTIONS

The ROD for ST-I0 was signed in September 2005 documenting the selected remedy for cleanup of groundwater associated with known releases at the Site (USAF, 2005).

3.3.1 Remedial Action Objectives

Based on an evaluation of site conditions, an understanding of the contaminants, the results of the risk assessments, and an analysis of ARARs, the ROD identified the following RAOs for ST-I0:

• Protect potential future human' receptors from exposure to contaminated shallow • groundwater • Restrict the use of shallow. groundwater until the shallow groundwater is cleaned up • Monitor the progress ofthe groundwater cleanup ofbenzene, naphthalene, and arsenic

COCs and deanup concentrations are listed in the following table.

Contaminants of Concern and Cleanup Criteria at ST-IO Cleanup Criterion Contaminant of Concern (/.l21L) Basis for Selection

Arsenic 10 MCL ,J Benzene 5 MCL Naphthalene 18 Risk-based concentration* *Site-specific concentration calculated based on USEPA Region III guidance.

3.3.2 The Selected Remedy

The selected remedy at ST -10 was FFS Alternative 2A: Groundwater Monitoring and ICs. The

remedy address~s groundwater contamination and potential future exposure to contaminated groundwater. The major components of the selected remedy consist of the following:

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• Perform groundwater monitoring, statistical evaluation of trends in concentrations of constituents requiring remediation, and five-year reviews; • Initiate further Oxygen Release Compound® (ORC®) treatment if arsenic, benz:ene, and • naphthalene concentrations do not continue to sufficiently decline and attain cleanup criteria; and • Implement and maintain ICs in the form of groundwater use restrictions until the cleanup criteria are achieved for arsenic, benzene, and naphthalene.

3.3.2.1 Groundwater Monitoring, Statistical Trend Evaluations, and Potential Further Treatment

Alternative 2A continues the ORC® injection treatability study performed as part of the RI in 2004. The treatability study was successful in reducing the concentrations of benzene and naphthalene, and the selected remedy continues the treatability· study through additional groundwater monitoring with potential treatment if cleanup criteria are not met.

As described in the ROD, the groundwater monitoring program included in this alternative will be used to:

1. assess the effectiveness of ·ORC® in accelerating biodegradation of benzene and naphthalene within the Northern and Southern Plumes; • 2. assess the reduction of arsenic through precipitation processes in the Central Plume (which is linked to TPH degradation); 3. collect additional data over time to determine trends in arsenic, benzene, and naphthalene concentrations and determine if additional action is required; and 4. target areas (if any) where additional treatments may be needed if an increase in concentrations (i.e., rebound for benzene and naphthalene) occurs or if biological degradation is not sufficient to reduce concentrations (i.e., arsenic)to cleanup criteria.

The ROD requires post-injection groundwater monitoring events 12, 18,24,36,48, and 60 months following the ORC® injection, followed by a monitoring event every two years for the remaining duration of 25 years (10 events) until:

1. the cleanup criteria are determined to be achieved (at which point ICs can be removed); 2. it is demonstrated that the plume continues to be stable (and ICs must remain in place); or 3. additional action is triggered according to the criteria defmed below.

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Dissolved and total arsenic, TPH, and geochemical and field parameters are to be monitored during the 12-, 18-,24-,36-,48-, and 60-month sampling events, as well as during, the biennial monitoring events through the remaining duration of 25 years. Benzene and naphthalene are to be monitored • during the 18-, 36-, 48-, and 60-month sampling events because the treatability study revealed that the majority of benzene and naphthalene concentrations were already below cleanup criteria and the cleanup timeframes for these chemicals was expected to be less than 5 years. ROD Table 2-3 adds anions, alkalinity, methane, ethane, ethene, and PLFA to the analytical suite and lists analytical methods. Table3.1 summarizes the monitoring program based on the foregoing description, Table 2-3 of the ROD, and Table 4-2 of the FFS.

The remedy for the Central Plume involves long-term monitoring of the arsemcand TPH in groundwater to determine if current naturally-occurring decreasing trends in arsenic concentrations are continuing or if arsenic concentrations show an increasing trend (as defmed below). Monitoring for TPH is included in the remedy for arsenic because a decrease in biological degradation of TPH· will be necessary for groundwater geochemistry to revert back to normal oxygen levels, thereby causingarseriic to precipitate into solid form within the soil formation and arsenic concentrations in groundwater to decrease Therefore, although TPH was not determined to be a constituent requiring remediation, TPH in groundwater at the site will be monitored in conjunction with the remedy for arsenic. •

To determine trends in arsenic concentrations at the site, the ROD states that the arsenic (dissolved and total) analytical data fOT the Central Plume monitoring wells will be statistically evaluated after each sampling event. If the statistical analysis indicates an increasing arsenic concentration trend, then quarterly monitoring is to be performed for one year to better understand the cause of the increase. Monitoring would includeanaJysis of total and dissolved arsenic, TPH, and field and geochemical parameters. If an increasing concentration trend is observed in arsenic concentrations after a year of quarterly monitoring and no plausible explanation suggests that the trend will go downward, then treatment (e.g., ORC® injection) of the Central Plume (or portions thereof that did not meet the cleanup criteria) will be proposed to address arsenic concentrations above the cleanup criteria.

Similarly, following the 18-, 36-, 48-, and 60-month post-ORC®-injection monitoring events, if a rebound in the concentrations of benzene or naphthalene is observed, an assessment is to be performed to determine whether an additional ORC® injection or other measures, such as longer 46 • P:IProjects\Andrews AFB EnvironmentalIFive-year reviewsl4.0 _ OeliverablesI4.1_ReportslFinal\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting. Inc. Project Number 3350092494 (Revised March 2011)

groundwater monitoring period are warranted in the Northern and Southern Plumes. Based on professional judgment, three trigger level conditions were developed to determine when additional • treatment or additional groundwater monitoring may be necessary. Additional ORC® injection or longer groundwater monitoring will be proposed to USEP A and MDE if the following occurs as a persistent phenomenon (i.e., an elevated concentration over three consecutive monitoring periods from the wells located within the source area):

1. Rebounded concentrations of benzene or naphthalene greater than 1o percent of original pre-remediation concentrations; or 2. Rebounded concentrations of benzene or naphthalene greater than 10 times the cleanup criteria; or 3. Rebounded concentrations of benzene or naphthalene greater than 33 percent of the difference between original pre-remediation concentration and the concentration reached during active remediation~

Additionally, as part of the CERCLA five-year review process, the concentrations of benzene and naphthalene and the arsenic statistical trends are to be reviewed. If the arsenic concentration trends do not indicate a statistically significant decrease in arsenic concentrations, the quarterly monitoring identified above along with ORC® treatment of the Central Plume will be proposed. Similarly, as part of the CERCLA five-year review process, the concentrations of benzene and • naphthalene in groundwater is to be further evaluated against the cleanup criteria to determine whether degradation continues to decrease concentrations or whether any additional remediation (e.g., additional ORC® treatment) should be proposed for the Northern and Southern plumes. Based on the success of the treatability study and decreasing trends prior to the treatability study, rebound in benzene and naphthalene concentrations was not expected in the ROD.

As discussed in the ROD, the estimated time required to achieve the cleanup criteria for Alternative 2A varies widely because of the limited data set available for modeling estimated timeframes. The estimated timeframe. to achieve the cleanup criteria for the Central Plume could be from 3 to 25 years, with the mid-point of 10 years, subject to refmement asmore data are collected as part of the groundwater monitoring program. Based on cleanup timeframe modeling and the results of the treatability study, the estimated remediation tirneframe for benzene and naphthalene as stated in the ROD, is less than five years. As a result,the proposed timeframe for the groundwater monitoring program is 25 years.

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3.3.2.2 Institutional Controls' Because the selected remedy for ST -10 leaves contaminants in place at levels that do not allow • unlimited use and unrestricted exposure, the remedy includes Ies to ensure that the contaminants do not pose an unacceptable risk to human health or the environment during the time until cleanup criteria are attained. The general areas for which Ies are to be implemented are illustrated on Figure 3.1. The Ie objectives are as follows:

1. Prohibit the use of groundwater potentially impacted by ST -10, other than for environmental monitoring or testing, until cleanup criteria are met for arsenic,benzene, and naphthalene; 2. Ensure that activities on Base do not damage or interfere with the monitoring wells or the ability to undertake required environmental monitoring or testing; 3. Ensure any proposed changes in land use are consistent with Ies; 4. Ensure any proposed construction activities at ST -10 are evaluated with regard to risks posed by compounds at the site, and the potential for construction to exacerbate site conditions. The nature of the site construction may require additional health and safety controls or engineering controls. . 5. Prohibit contact with groundwater at ST-IO by Joint Base Andrews maintenance workers; and 6. In the event that groundwater impacted by ST-IO is withdrawn during construction activities, ensure that it is appropriately stored, managed, and disposed. •

To meet the Ie objectives, the ROD states that the following actions and restrictions shall be implemented and maintained on the groundwater areas identified in Figure 3.1:

1. Employ USAF administrative procedures to track all development activity at Joint Base Andrews which requires excavation to ensure that no project violates groundwater use restrictions for ST-IO. Existing procedures are included in USAF Instruction (AFI) 32­ 1021, Planning and Programming of Facility Projects, and work request procedures under AFI 32-1001, Operations Management, or their equivalents if amended. USAF instructions and procedures require coordination with and prior approval by environmental personnel if a proposed project is located on or near an ERP site. Base personnel will verify location of potentially contaminated sites via the available information (maps, documents, databases, GIS, etc.). The USAF will ensure that these or equivalent instructions, processes,and/or requirements will be complied with for all proposed construction or soil-disturbing activities within ST -10. 2. Post signs meeting the following requirements at the site within 120 days of ROD signature: • '. Signs shall indicate that the groundwater presents a potential hazard and that construction, • excavation and groundwater use are prohibited

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• Lettering shall be legible from a distance of at least 25 feet • Signs shall contain contact information for the ERP Project Manager for long-term • oversight . • Signs shall be visible from surrounding areas and at potential routes of entry 3. 'Employ access restrictions at the site. Access to ST-lOis extremely limited because it is located within the airfield controlled by Joint Base Andrews securitY personnel. Only authorized adults will be permitted to access the area and must be escorted by a DoD employee with the proper credentials (i.e., flight line badge). No trespassers or other parties will be permitted to access the site; 4. Update the BGP. The BGP implements "zoning-like" requirements atJoint Base Andrews; The General Plan is one of the first and primary documents to be reviewed when· installation personnel are proposing projects on the installation. AFI 32-7062 requires this comprehensive planning document for the establishment. and maintenance of administrative and physical controls. The BGP resides in the office of the Base· Community Planner. The USAF will update the detailed map included in the BGP showing the location and dimensions of ST -10 and the extent of related groundwater contamination. This information as well as ICs, boundaries, and expected durations of the ICs will be added to the existing IC section of the BGP within 90 days of ROD signature. This section includes a comprehensive listing and map of all ICs on the installation. The USAF may change the BGPand agrees to notify USEPA and MDE at least 30 days prior to a change which addresses or affects ICs at·ST~lO.

The following restrictions will be incorporated mto the BGP and cross-referenced to the ICs map: • 1. No drilling for or use of groundwater beneath ST-IO, other than for environmental monitoring or testing, until the concentration of arsenic, benzene, and naphthalene in groundwater are at such levels to allow for unlimited use and unrestricted· exposure.

11. Any proposed activity or construction on an ERP site requires an "ERP Waiver to Construct" memorandum, approved and signed by USAF Headquarters Air Mobility Command; 5. The. USAF shall not modify or terminate ST-IO ICs without approval by USEPA and MDE. The USAF shall seek prior concurrence before any anticipated action which may disrupt the effectiveness of the ICs.

1. For proposed land use changes which do not include .transfer of the property, the USAF will notify USEP A and MDE at least 45 days in advance of any anticipated base proposal inconsistent with the use restriction and assumptions described herein, any anticipated action which may disrupt the effectiveness of the ICs, or any action which may alter or negate the need for the IC.

11. The USAF will provide notice to USEPA and MDE, consistent with CERCLA Section 120(h), at least six months prior to any transfer by deed of ST-IO so that USEPA and MDE can be involved in discussions to ensure that appropriate provisions are included in the transfer terms or conveyance documents to maintain effective ICs. If it is not possible for the facility to notify USEPA and MDE at . least six months prior to any transfer by deed, then the facility will notify USEP A • 49 P:IProjectslAndrews AFB EnvironmentallFive-year reviewsI4.0_DeliverablesI4.1_ ReponslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

and MDE as soon as possible but no later than 60 days priorto the transfer by deed of any property subject to ICs. In addition to the land transfer notice and discussion provisions above, the USAF further agrees to provide USEPA and MDE with similar notice, within the same time frames, as to federal-to-federal • transfer of property accountability and administrative control of ST -10. The USAF shall provide a copy of the executed deed to USEPA and MDE. The USAF will provide similar notification to USEPA and MDEas to leases of the ST-I0 area, in addition to transfers by deed. 6. The USAF will conduct periodic monitoring of the ICs at ST-I0 (at least annually). The USAF shall provide notice to USEP A and MDE within 10 business days if it discovers any activity that is inconsistent with the IC requirements, objectives or controls, or any action that may interfere with the effectiveness of the ICs. The USAF shall include in such notice a list of corrective actions taken or planned to address such deficiency or failure. Any activity that is inconsistent with the IC objectives or use restrictions, or any other action that may interfere with the effectiveness of the ICs, will be addressed by the USAF as soon as practicable. . 7. The USAF will fuUycomply with and be accountable for the lCs identified herein and will timely submit to the USEPA and MDE an annual monitoring report on the status of the ICs, including the operation and maintenance and monitoring of ICs, and how any IC deficiency or inconsistent land use has been addressed.

1. The Ie anriual monitoring report shall'be filed in the Administrative Record and Information Repository.

11. The IC annual monitoring report is not subject to approval and/or revision by the USEPA and MDE and will be provided to each for informational purposes only. 8. The USAF is responsible for implementing (to the degree controls are not already in place), monitoring, maintaining, reporting on, and enforcing the identified ICs. If the • USAF determines that it cannot meet specific IC requirements, it is understood that the remedy may be reconsidered and that additional measures may be required to ensure the protection of human health and the environment. The USAF shall obtain the concurrence of USEPA and MDE prior to modifying or terminating any ICs, objectives, or IC implementation actions.

ICs are not required for soil at the site.

3.3.3 Remedy Implementation

Implementation of the groundwater remedy began in October 2004 with the injection of a commercially available source of slow-release oxygen (ORC-Advanced®) to promote enhanced microbial degradation of the petroleum compounds in the subsurface. Approximately 11 ;000 pounds of ORC-Advanced® were injected into the areas of the northern and southern plumes via 190 injection points, in September and October 2004. The injection was performed as a treatability study, but decreases in all three COCs were observed in post-treatment sampling results 3 and 6

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months after injection. Therefore, the treatability study actions were incorporated into the final • remedy. 3.3.4 System Operations/Operation and Maintenance

The selected remedy for ST -10 does not include remedial systems that require long-term operation and maintenance.

3.4 ST-I0 PROGRESS SINCE LAST FIVE-YEAR REVIEW

This is the first five-year review for ST-I0.

3.5ST-I0·FIVE-YEAR REVIEW PROCESS

3.5.1 Community Involvement

The USAF has maintained a public involvement and infomiation program for the ERP since 1990 and maintains an Administrative Record as required by CERCLA. The Administrative Record is maintained at the Environmental Flight, 3466 North Carolina Avenue, Joint Base Andrews. For the convenience of the public, a copy of the Administrative Record is maintained in an Information • Repository located at:

Prince George's County Memorial Library-Surratts-Clinton Branch 9400 Piscataway Road Clinton, MD 20735

Community involvement activities for this five-year review consisted of publishing a notice in two local newspapers announcing the USAF's intent to perform the five-year review and providing information where and how the public could obtain additional information. The notice appeared in the Prince George's County Gazette on December 3, 2009, and in the Capital Flyer on December 18,2009..A copy of the notice is provided in Appendix A.

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3.5.2 Document Review The five-year review included review of relevant documents including the following: • • Final Remedial Investigation, ST-IQ, PD-680 Spill Site (CH2M HILL, 2005a) • Focused Feasibility Study Report, ST -10, PD-680 Spill Site (CH2M HILL, 2005b) • Final Record of Decision ST-I0, PD-680 Spill Site (USAF, USEPA, and MDE, 2005) • Andrews Air Force Base General Plan, Land Use Control Implementation Plan, ST-IO (USAF,2007) • Report of Annual Land Use Control Monitoring, Andrews Air Force Base, Maryland, October 2007 - December 2008 (MACTEC, 2009) • General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland (PBS&J,2009)

3.5.3 Applicable or Relevant.andAppropriate Requirement Review

The ARARs presented in Appendix B of the ROD are reprinted and appended in Appendix C of this report. These standards and regulations were current at the signing of the ROD and as part of the five-year site review, have been reviewed for changes that could affect protectiveness. None of the ARARs listed in Appendix C have had changes since signing of the ROD that affect the • protectiveness of the implemented remedial action. Changes to ARARs and TBCs that pertain to risk assessment are discussed in Subsection 3.6.2 ..

3.5.4 Data Review

This five-year review included review of groundwater analytical data from ST-I0 monitoring wells for the period from March 2001 through September 2009, with a focus on benzene, naphthalene, and arsenic, theCOCs identified for ST -10. These were the most recent data available at the time this report was drafted.

Benzene. Analytical data for 13 monitoring wells (Table 3.2) spanning the period from March 2001 to September 2009 were reviewed to assess whether a rebound had occurred that could trigger additional action pursuant to ROD requirements (Subsection 3.3.2.1). The majority of analytical results after ORC® injection are less than the cleanup criterion of 5 ~glL, and many are less than analytical reporting limits. Seven wells (MW01-STlO, MW02-STlO, MW03-STlO, MW04-STIO, MW06-STlO, MWI5-STI0, and MWI6-STlO) had benzene concentrations less than the cleanup criterion in the baseline monitoring. Benzene concentrations in these wells have remained less than 52 • P:\Projects\Andrews AFB EnvironmentalIFive-year reviews\4.0_ Deliverables\4.1_ ReportslFinal\AndrewsAFB _5-Yr Review_Revised March 2011.doc J.oint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

the cleanup criterion and typically less than the reporting limit. In four wells (MW08-STIO, MWI2-STlO, MWl3-STIO, and MWI4-STl9), baseline benzene concentrations were greater than • the cleanup criterion, but quickly decreased to less than the cleanup criterion and have not rebounded above the cleanup criterion or above trigger conditions. In well MW09-STl 0, benzene concentrations were less than the cleanup criterion in ba'seline monitoring, increased substantially in the first 6 months following ORC® injection, and then decreased to, and have remained at, very low values. Only one well, MWlQ-STlO within the northern plume, has not attained the cleanup criterion for benzene. The benzene concentration in this well, which was 8.8 Ilg/L in the baseline sample, decreased to 3 Ilg/L in January 2005,3 months after ORC® injection, then increased to 22 j.tg/L in June 2006. Concentrations decreased to 6 Ilg/L by September 2008, but increased, again, to 20M Ilg/L in the September 2009 sample, with "M" indicating the value was estimated because of a matrix effect.

The data review indicates that benzene in MWI O-STl 0 has rebounded from low active remediation

concentrations to concentrations greater than 1o percent of b?-seline ~oncentrations during the last five sampling events 'and has exceeded 33 percent of the difference between baseline and low active remediation concentrations in the last five sampling events. Even if the September 2009 data are not considered because of matrix effects and high pre-baseline concentrations are • considered; concentrations greater than 10 percent of pre-baseline concentrations have been reported during the last four sampling events. Therefore, the conditions for consideration of additional remedial action are triggered (Subsection 3.3.2.1).

Figure 3.2 shows concentration versus time plots of the benzene data.

Naphthalene. Review of the analytical data (see Table 3.2) for naphthalene shows that naphthalene concentrations were less than the cleanup criterion in baseline or pre-baseline samples in 9 of the l3 wells and have remained less than the cleanup criterion in those wells since ORC® injection in 2004. One well had naphthalene exceeding the cleanup criterion in the 3-month sample, but not in subsequent samples. Among the remaining three wells, well MWI4-STlOhad a baseline concentration of 73 Ilg/L, several times greater than the cleanup criterion of 18 Ilg/L; however, concentrations in this well quickly decreased to less than reporting limit values and have remained at very low concentrations through September 2009. Well MW03-STlO has shown fluctuating concentrations, ranging from 45 Ilg/L in the baseline sample to a low of 10 Ilg/L in • 2006, 29 Ilg/L in 2008, and 18 Ilg/L in September 2009. Additional sampling is needed to assess

53

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whether this decreasing trend continues. Naphthalene concentrations in MWI0-STlO within the

northern plume h~d a baseline value of 35 /-lglL (and as great as 257 /-lglL prior to the baseline sample round), and although concentrations decreased to less than 4.7 /-lglL three months after • ORC®, they have shown an increasing trend since .then. The naphthalene concentration in the September 2009 sample was 71 /-lg/L.

The data review indicates that naphthalene in MW10-ST10 has rebounded from low post-injection concentrations to concentrations greater than 10 percent of baseline concentrations during the last five sampling events and has exceeded 33 percent of the difference between baseline and low post­ injection concentrations in the last four sampling events. Therefore, the conditions for consideration of additional remedial action are triggered (Subsection 3.3.2.1). Even when high'pre­ baseline concentrations are considered, concentrations greater than 10 percent of pre-baseline concentrations have been reported during the three of the last four sampling events .

. Concentration versus time plots for naphthalene data for 13 monitoring wells spanning the period from March 2001 to September 2009 are presented in Figure 3.3. "

Arsenic. TheMann-Kendall Test was used to evaluate arsenic trends for both totaland dissolved analytical fractions in Central Plume wells (MW02-STlO, MW03-STlO, and MW04-STlO). The • results are shown in AppendixC and summarized in the following table. As can be seen, the S statistic was positive for total and dissolved fractions in all three wells, and the Mann-Kendall Test indicated probable increasing dissolved concentrations in MW02-ST10 and stable or no trend conditions for remaining fractions and wells. Because a significant decrease is not indicated, the conditions for consideration of additional remedial action are triggered(Subsection 3.3.2.1).

Summary or Mann-Kendall Statistical Analysis - Arsenic iIi'ST-lO Central Plume Wells Concentration (llg/L) Mann-Kendall Monitorin2 Well Sept 2004/Sept 2009 Statistic Mann-Kendall Trend MW02-STl 0 (Total) 28/34 15 NT MW02-STlO (Diss.) 23/37 11 PI MW03-STlO (Total) 130/120 . 13 NT MW03-STlO (Diss.) 1501130 2 NT MW04-STlO (Total) 1201130 19 S MW04-STl 0 (Diss.) 1101140 5 NT Notes: D = decreasing trend, NT = no trend, I = increasing trend, PI = probably increasing trend, S = stable

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3.5.5 Site Inspection

A LUC inspection was performed at ST-10 in January 2009 as part of a comprehensive LUC • inspection at Joint Base Andrews CERCLA sites with RODs (MACTEC, 2009b). The ST -10 site was viewed from outside the airfield/flight line security fence on October 21, 2009. The inspection confirmed general site conditions and land use assumptions.

3.5.6 Interviews

No interviews were conducted with community members in regard to ST-10. A public notice was published in two area newspapers in December 2009, indicating that the reVIew process was underway and providing contact information for questions or comments. No inquiries from the general public were received. Input on the review process was obtained from representatives of the USEPA, MDE, and Prince George's County through their participation in the Tier 1 partnering team and by their review ofpreliminary drafts of this document.

3.6 ST-I0 TECHNICAL ASSESSMENT

• 3.6.1 Question A: Is the remedy functioning as intended by the decision documents?

Yes, the remedy is functioning as intended by the ROD, as discussed further below.

Implementation of Institutional Controls and Other Measures. The Joint Base Andrews Environmental Flight developed a LUCIP for the ST-10 site in March 2007 (USAF, 2007), and provided it to the Joint Base Andrews Community Planner so that LUCIP fOf" the site could be incorporated into the BGP, the Base's comprehensive land use planning document. The LUCIP presents specific requirements for the establishment, implementation, and maintenance of LUCs at , ST-10.

Joint Base Andrews has posted signs at ST -10 to indicate that groundwater at the site presents a potential hazard and that construction, excavation, and groundwater use are prohibited (MACTEC, 2009).

Electronic map layers showing the locations of restricted areas associated with ERP sites have been posted on the official Joint Base Andrews GIS (Andrews AFB Geo-Base) to assist all organizations with project planning and design tasks (MACTEC, 2009). • 55 P:IProjectslAndrews AFB EnvironmentallFive-year reviewsI4.0_DeliverablesI4.1_ ReportslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

A Waiver-to-Construct is required for all proposed construction on an ERP site (AFI 32-1021). A Waiver-to-Construct means the proposed construction has been evaluated with respect to site • activity and environmental risks proposed by the construction and ultimate use of the facility. The BGP contains a listing of ERP sites as well as a map showing their locations (PBS&J, 2009). A Waiver to Construct was signed for the proposed construction of a cargo-handling facility at ST-IO. The BGB also identifies ST-lO as an area where LUCs have been established.

In addition, groundwater is prohibited from being used for potable purposes anywhere on Base (PBS&J, 2009), and COMAR 26.03.01.05 prohibits installation of new water supply wells.

Annual LUC monitoring has been completed twice since the LUCIP was put in place in 2007. The most recent report, covering calendar year 2008, concluded that all required LUCs have been implemented for ST-IO (MACTEC, 2009). The 2008 report did not identify inconsistent uses or LUC deficiencies, or activities that could interfere with the effectiveness of the land use restrictions and controls. The report for 2009 was being prepared at the time of this five-year review.

Remedial Action Performance. Based on available data, the remedial action has resulted in • attaining cleanup criteria for benzene and naphthalene at all monitoring wells except MWIO~ST10. Benzene and naphthalene concentrations have rebounded in this monitoring well, and conditions for consideration of additional action have been triggered.

Arsenic concentrations do not show decreasing trends, and conditions for consideration of additional action have been triggered.

System Operations/Operation and Maintenance. The selected remedy .at ST-IO does not include remedial systems that require operation and maintenance. Ground water monitoring is being performed as required by the ROD.

In lieu of the CLP method discussed in the ROD, EPA Method 8260B for volatiles can be used for naphthalene analyses. The laboratory standards used for CLP Method OLM 03.2 and CLP Method SOMOL2 do not include naphthalene; therefore, naphthalene cannot be measured by routine CLP volatile analysis. Method 8260B can provide reporting limits well below the cleanup criterion for naphthalene and at an expected lower cost than the CLP method. In addition, use of Method 56 • P:IProjectslAndrews AFB Environmental\Five-year reviewsl4.0 _ DeliverablesI4.1_ ReportslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consuiting. Inc. Project Number 3350092494 (Revised March 2011)

8260B would increase analytical consistency among sites with groundwater monitoring at Joint • Base Andrews. Cost of System Operations/Operation and Maintenance. Estimated and actual costs for RA-O are shown in the following table. As is shown, actual costs are close to estimated costs and do not suggest operational issues.

ST-IO Annual System Operations, Monitoring, and Maintenance Costs Calendar Year Year Estimated 'Cost) Current/Actual Cost Description 1 2005 $14,481 $15,000 RA-O 2 2006 $72,877 $52,000 RA-O 3 2007' $36,439 $42,000 RA-O 4 2008 $36,439 $58,000 RA-O 5 2009 $47,239 $63000 RA-O Notes: The initial injection of ORC® substrate was in September and October 2004. Operations, monitoring and maintenance costs have been assumed to begin in 2005. I Estimated costs from ST-lO Record of Decision Table 2-3

Expected Progress Towards Meeting RAOs. See Remedial Action Performance above.

• 3.6.2 Question B: Are the exposure assumptions, toxicity data, cleanup levels, and RAOs, used at the time ofthe remedy still vaUd?

Yes, the exposure assumptions, toxicity data, cleanup levels and RAOs remain valid.

Changes in Standards and To Be Considered Values. This five-year review did not identify ARARs that have been promulgated since the ROD was signed. '-

Changes in Exposure Pathways. The construction of the planned cargo-handling building at ST-IO could result in the vapor intrusion exposure pathway being complete because of the presence of VOCs in groundwater. To evaluate whether this exposure pathway could potentially be significant, based on current (most recent) concentrations ofvOCs in groundwater, groundwater data were compared to vapor intrusion screening values published by USEPA (OSWER Draft Guidance for Evaluating the Vapor Intrusion to Indoor Air Pathway from Groundwater and Soils [2002]), modified to account for commercial/industrial exposures (8 hours per day, 5 days per week) as opposed to residential exposures, and updated with current toxicity values. The comparison indicated that benzene and 1,2,4-trimethylbenzene were reported at concentrations in • excess of the vapor intrusion screening values. Concentrations of benzene in excess of screening

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No other changes in current or reasonably foreseeable future site conditions that affect exposure pathways were identified as part of this five-year review.

Changes in Risk Assessment Methodology, Toxicity, and Other Contaminant Characteristics. The baseline risk assessment for ST-IO identified eighteen COPCs in groundwater and identified three (arsenic, benzene, and naphthalene) as COCs requiring remediation. The fifteen COPCs that were not identified as COCs that required remediation were established as such because they did not contribute significantly to risks and/or were detected in only a few of a large number of wells.

The toxicity values for the COPCs and COCs were reviewed to determine if any changes (updates) to toxicity values could change the COCs that were identified as chemicals requiring remediation. Of the COPCs identified in ST-IO groundwater, toxicity values selected in accordance with the • USEPA policy on human health toxicity values in Superfund risk assessments (USEPA, 2003) have been updated as shown in Table 3.3.

Collectively, none of the updated toxicity values or draft proposed updated toxicity values would change the conclusions of the risk assessment or selection of COCs requiring remediation.

The only change to risk assessment methodology that would have a bearing on the ST-10 risk assessment is the pUblication of Risk Assessment Guidance for Superfund (RAGS), Part E, Inhalation Risk Assessment. The RAGS Part E guidance would stipulate that inhalation reference concentration and unit risk values should be used instead of inhalation reference dose and cancer slope factor values to quantify inhalation toxicity and risks; However, us~ of reference concentration and unit risk values instead of reference dose and cancer slope factor values would not have a bearing on the results or conclusions of the risk assessment.

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Implications on Cleanup Levels. The groundwater cleanup levels for the COCs were based on theUSEPA MCLs for arsenic (10 )lg/L) and benzene (5 )lg/L). The groundwater cleanup level for • naphthalene was derived as a risk-based value of 18 )lg/L. None of the identified changes in exposure pathways, risk assessment methodology, or toxicity values would change the cleanup levels or call into question the protectiveness of the remedy.

3.6.3 Question C: Has any other information come to light that could caD into question the protectiveness of the remedy?

No. No other information has come to light that calls into question the protectiveness of the remedy other than the potential vapor inhalation risk if the cargo handling building is constructed at the site.

3.6.4 Technical Assessment Summary

Based on the data reviewed, the remedy is, for the most part, functioning as intended by the ROD; however, there has been rebound of benzene and naphthalene in one well, and arsenic concentrations in the Central Plume are not decreasing. There have been no changes in site conditions that affect protectiveness. There have been no changes to toxicity factors for COCs or changes to risk assessment methodology that would change the protectiveness of the remedy. • I . There·is no information that calls into question the short-term protectiveness of the remedy.

3.7 ST-IO ISSUES

The following table summarizes the issues identified or Site ST-I0 during this five-year review. The table only lists issues that affect current and/or future protectiveness.

Affects Protectiveness Issues (YIN) Current Future The construction of the planned cargo-handling building at ST -10 could result in the vapor intrusion exposure pathway being complete because ofthe N y presence of VOCs in groundwater.

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Affects Protectiveness Issues (yIN) Current Future • Benzene and naphthalene concentrations in MW 1O-STl o have rebounded, and conditions for consideration of additional action have been triggered. N y Non-decreasing arsenic concentrations in the Central Plume have also triggered the need for consideration of additional action. Reduction in monitoring requirements at MW 1O-STl 0 and MW03-STl 0 according to the schedule identified in the ROD may limit futUre assessment N y of remedy performance at these wells.

3.8 ST-I0 RECOMMENDATIONS AND FOLLOW-UP ACTIONS

The following table summarizes recommendations and follow-up actions identified for Site ST-IO . during this five-year review. The table only lists recommendations and follow-up actions for issues that affect current and/or future protectiveness.

Follow-up Action Affects Recommendations 1Follow-up Party Oversight Milestone Protectiveness Actions Responsible Agency Date (yIN) • Current Future Evaluate the vapor intrusion exposure pathway before construction ofthe cargo-handling building to ensure worker safety and so that engineering controls USAF USEPA 06/30/2011 N y can be planned, as appropriate. USAF should keep USEPA informed of plans and activities pertaining to construction of the facility. Evaluate the additional injection of ORC® in the Central Plume to accelerate degradation of organics and reduction of arsemc concentrations. Additional injection of ORC® should also be USAF USEPA 06/30/2011 N y evaluated for the Northern Plume to accelerate degradation of organics contributing to high benzene and naphthalene concentrations at MWIO-STI0. 60 • P:\Projects\Andrews AFB EnvironmentallFive·year reviewsl4.0 ~DeliverablesI4.1_ ReportslFinal\AndrewsAFB_5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

Follow-up Action Affects Recommendations 1Follow-up Party Oversight Milestone Protectiveness . Actions Responsible Agency Date • (YIN) Current Future Continue to sample MWI0-STlO and MW03-STl 0 on an annual basis with analysis for YOCs, TPH-DRO, TPH-GRO, totaVdissolved arsenic, anions, alkalinity, methane, ethane, USAF USEPA 12/3112010 N y ethene, and field and geochemical parameters until cleanup criteria for benzene and naphthalene are attained. Other monitoring wells should be sampled as described in Table 3~ 1.

3.9 ST-I0 PROTECTIVENESS STATEMENT

The selected remedy for ST-lOis currently protective. If and when the cargo .building is planned to be constructed, a vapor inhalation evaluation will need to be conducted to deterrnineif there is the potential for a vapor inhalation risk, so tha.t engineering measures can be implemented in the design • ofthe cargo building. 3.10 ST-I0 NEXT REVIEW

ST-lOIS a statutory site that requrres ongoing five-year reviews. The next reVIew will be performed within five years of the completion of this five-year review report. The completion date is the date of the signature shown on the signature cover attached to the front of this report.

3.11 ST-I0 REFERENCES

CH2M HILL, 2004a. Final Basewide Background Study Report, Andrews Air Force Base, Maryland, March.

CH2M HILL, 2004b. Final Andrews AFB ST-10, PD-680 Spill Site - ST-lO ORC Pilot Test, Memo Work Plan, September.

CH2M HILL, 2005a. Final Remedial Investigation, ST-I0, PD-680 Spill Site, Andrews Air Force Base, Maryland, June.

CH2M HILL, 2005b. Focused Feasibility Study Report, ST-10, PD-680 Spill Site, Andrews Air Force Base, Maryland, July. . • 61 P:\Projec\SlAndrews AFB Environmental\Five-year reviews\4.0 _Deliverables\4. 1_Reports\FinallAndrewsAFB _ 5-Yr Review_Revised March 201 I.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 201 I)

Dames & Moore, Inc., 1992. Groundwater Contamination Survey. Andrews Air Force Base; • Maryland, April.

IT Corporation, 2001, 2002. Analytical Results from Annual Monitoring Well Sampling at Andrews Air Force Base, Maryland. Unpublished data.

MA~TEC, 2009. Report of Annual Land Use Control Monitoring, Andrews Air Force Base, Maryland, October 2007 - December 2008, February.

MDE (Maryland Department of the Environment, Hazardous and Solid Waste Management Administration), RCRAPhase 2 Facility Assessment. Andrews AFB. MDRF A 88- 009.MDE 1991. Tank Removal/Abandonment Form, April 11.

MDE (Maryland Department of Environment, Waste Management Administration, Oil Control Program), 2003. Maryland Environmental Assessment Technology for Leaking Underground Storage Tanks, Revised February.

PBS&J, 2009. General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland, December.

USAF (U.S .. Air. Force), 2007. Andrews Air Force Base General Plan, Land Use Control Implementation Plan, ST-IO, Andrews Air Force Base, Maryland, March.

USAF, USEPA, and MDE (U.S. Air Force, U.S. Environmental Protection Agency-Region III, and Maryland Department of the Environment), 2005. Final Record of Decision ST-lO, PD­ • 680 Spill Site, Andrews Air Force Base, Maryland, September. usAF (U.S~ Air Force), 2006. Report of Annual Land Use Control Monitoring, Andrews Air Force Base, Maryland, September 2005 - December 2006.

USEPA (U.S. Environmental Protection Agency), 2003. Human Health Toxicity Values ill Superfund Risk Assessments, OSWER No. 9285.7-53, December.

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4.0 ST-14 FIVE-YEAR REVIEW

The ROD for ST-14 was signed in September 2007. Remedial actions were initiated in May 2006 • with the injection bf sodium lactate solution as part of a treatability study and predesign investigation to support in-situ reductive dechlorination of chlorinated hydrocarbons. Because hazardous substarices, pollutants, or contaminants remain at the site above levels that allow for unlimited use and unrestricted exposure, this is a statutory review under CERCLA.

Infomlation in Subsections 4.1, 4.2, and 4.3 is based primarily on material presented in the ROD (USAF, USEPA, and MDE, 2007).

4.1 ST-14 DESCRIPTION AND CHRONOLOGY

The ST -14 Site, the East Side Gas Station Site, is located east of the flight line in the northeast portion of Joint Base Andrews (see Figure 1.2). The Site initially comprised the gasoline leaks from two 1O,OOO-gallon USTs and distribution lines at the former East Side Gas Station (Bldg 3487) on Fetchet Avenue (Figure 4.1), but was expanded as a result of a Dames "& Moore investigation in 1992 that revealed, in addition to the gasoline, the presence of TCE and carbon • tetrachloride apparently originating from sources upgradient of Building 3487. The area contains a number of low-rise office buildings, maintenance shops, and a soccer/softball field. A portion of the aircraft parking apron south of Building 3602 is included as part of ST -14. The gas station was built in 1945 as a full service station with two service bays, but was closed and converted to a convenience store in the early 1980s. The two 10,000-gallon USTs associated with the former gas station were removed in 1983.

Investigation of gasoline contamination associated with the USTs and distribution lines revealed the presence of TCE and carbon tetrachloride groundwater contamination that originated from sources upgradient of Building 3487. The TCE plume is approximately 1,800 feet long (up- to down-gradient) and 2,200 feet wide at its 5 IlglL boundary. Collocated within this large plume are smaller plumes of carbon tetrachloride (13 acres) and gasoline-related compounds (5 acres) (Earth Tech, 2007a). Although several minor releases within this industrial area of the Base may have contributed to the groundwater contamination, two main sources of TCE have been identified based on the geometry of the plume and soil sampling:

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1. A Former Aircraft Wash Rack (number T-3-189) located on the south side of a former • hangar west of Building 3602; and, 2. The Northern Fire Department Wash Site, believed to be the result of past releases by the Base Fire Department when they cleaned their fIre trucks near the former fIre station in Building 3621.

Building 3471, located upgradient of Building 3487 near the flight line, is also the site of a former UST. On October 7, 1993,a 1,000-gallon steel UST containing No. 2 fuel oil was removed at Building 3471 (IT, 1995).

ST-14 is an ERP site that is in the CERCLA process at Joint Base Andrews. A chronology of remedial studies~ investigations, and reports at ST-14 is presented below.

• 1983: Removal oftwo 10,000-gallon USTs (Dames & Moore, 1994) • 1983 to 1986: Removal of 250-gallon motor oil UST and visually contaminated soil (Dames & Moore, 1992) • 1984: Air Force installs 10 monitoring wells (Shaw, 2005) \ • 1985: Phase 1 Records Search (ES, 1985) • 1988 to 1989: Additional soil and groundwater sampling (USGS, 1990) • 1991 to 1992: Groundwater Contamination Study (Dames & Moore, 1992) • • 1993: Removal of 1,000-gallon UST at Bldg 3471 (IT, 1995) • 1996: Waterloo Innovative Technology Experiment (University ofWaterloo, 1996) • 1999 to 2000: Comprehensive Environmental Investigation (IT, 2000) • 2005: Comprehensive Environmental Investigation Addendum (Shaw, 2005) • 2006: Feasibility Study (Earth Tech, 2007a) • 2007: Pre-design Study (Earth Tech, 2007b) • 2007: Record ofDecision (USAF, USEPA, and MDE, 2007)

4.2 ST-14 BACKGROUND

4.2.1 Physical Characteristics

The land surface at ST-14, like most of 10intBase Andrews, is generally flat. The area comprises low-rise offIce buildings, hangars, roads, parking lots, and grassed areas. The site is bordered by tributaries to Cabin Branch· to the northeast. The shallow soils underlying the site generally comprise three stratigraphic lithologies: clayey, gravelly silt; an intermediate sand and gravel 64 • P:\Projects\Andrews AFB EnvironmentallFive-year reviewsI4.0_DeliverablesI4.1_ ReponslFinal\AndrewsAFB_5- Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 201 I)

stratum; and underlying silty fme sand (IT, 2000). The Calvert Formation, a regional aquitard beneath Joint Base Andrews, is generally encountered at 38 to 40 feet bgs in the upgradient portion • of the ST -14 area, although it outcrops a few feet below the top of the bank along the tributary of Cabin Branch on the northeast side of the site (Shaw, 2005). The Final Comprehensive Environmental Investigation (CEl) Addendum identifies three wetland areas in what are otherwise upland areas' of the site: an approximate 87- by 30-foot area adjacent to the former fIrehouse, Building 3623; an approximate 70-by 45-foot area behind the current firehouse, Building 3464; and an approximate 80-by 48-foot area approximately 200 feet east of Patrick Avenue.

Shallow groundwater at ST-14 is approximately 15 to 20 feet bgs within the: majority of the site, but gradually decreases to the northeast in rough proportion to the lowering land surface elevation towards the Cabin Branch tributaries. The downward migration of shallow groundwater is limited by the Calvert Formation at a depth of approximately 38 to 40 feet bgs.

Groundwater in the area of ST -14 general~y flows to the northeast. The hydraulic conductivity was estimated to be between 1.2x 10- 3 and 8.6x 10- 5 centimeters per second (IT, 1997). Corresponding groundwater velocities are estimated to be 5.8 to 85 feet per year based on a porosity of 0.3 and a • hydraulic gradient of 0.02 feet per feet from the flight line to the Cabin Branch tributary (IT, 1997). 4.2.2 Land and Resource Use

ST-14 is located ina developed part of Joint Base Andrews and current land use designations include aircnift operations and maintenance, administrative, community, and open space. Future land use is designated as aircraft operations and maintenance, administrative, and community (PBS&J,2009). There are numerous buildings on site that are used by workers, but no residential buildings are present. Only the western edge of the site is within the airfield/flight line security zone.

There are no potable water supply wells located at Joint Base Andrews, including ST -14, and there is no current use or exposure to groundwater. Groundwater at ST-14is not expected to be used for such purposes in the future. Joint Base Andrews is currently served by public water supplied by the WSSC, and, according to COMAR 26.03.01.05, wells cannot be installed in areas where public water infrastructure is available.

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No areas of archaeological or historical importance have been identified at ST-14.

·4.2.3 History of Contamination • 4.2.3.1 Groundwater

Groundwater contamination at ST-14 primarily consists of TCE (and its breakdown products cis­ 1,2-dichloroethene (1,2-DCE), and vinyl chloride); carbon tetrachloride; petroleum-related contaminants including benzene; toluene, 1,2-dichloroethane (1,2-DCA), ethylenedibromide, trimethylbenzenes, and xylenes; pesticides, including lindane and heptachlor epoxide; and inorganics (metals).

VOCs and SVOCs. TCE was detected in groundwater across the majority of the ST-14 area. As illustrated in Figure 4.1, a TCE plume approximately 1,800 feet long and 2,200 feet wide at its 5 IlglL edge was identified at ST-14 (Earth Tech, 2007b). Isoconcentration contours of TCE indicated four distinct areas of relativdy high concentration and suggested'p'otential upgradient sources in the vicinity. of monitoring wells MWI7-ST14 (TCE =1,600 IlglL), MWI1-STI4 (TCE = 1,400 IlglL), MW12-ST14 (TCE = 450 IlglL), and MW23-ST14 (TCE = 71 IlglL).

As a result of the lack of tetrachloroethene (PCE) detections at ST-14, TCE is believed to be the • parent compound released to the environment and not a PCE daughter product. TCE was commonly used as a degreaser by the USAF from the 1940s through the 1960s. Prior to remediation activities, ·evidence' of natural degradation via reductive dechlorination existed at the site as detections of cis-l,2-DCE (maximum detection of 220 IlglL in MWI7-ST14) and vinyl chloride (maximum detection of 5 IlglL in MW37-ST14). However, the persistence of TCE in

downgradient locations indicated that the rate of degradation rwas low or possibly stalled. Available data for soil and groundwater do not suggest the presence of chlorinated VOCs as non­ aqueous phase liquid.

Pre-remedial acti'on trends in concentrations of TCE could not be determined by analysis of data collected over a span of up.to 10 years. Variability in TCE concentrations of 1 to 2 orders of magnitude was observed in some monitoring wells. The reason for the variation in concentrations is not known, but could have resulted from variations in sampling protocol, plume migration, fluctuation in groundwater flow/level, or another mechanism (Shaw, 2005).

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Although TCEhas migrated significantly downgradient from its suspected source area(s), it has been detected in samples collected from seeps on the banks of two tributaries of Cabin Branch (IT, • 2000b), TCE has not been detected in MW36-ST14, which is screened in the Calvert Formation, indicating that TCE is not migrating vertically downward.

Carbon tetrachloride was detected historically in several monitoring wells in the northern portion of ST -14, and the MCL of 5 Ilg/L was exceeded in five monitoring wells. Isoconcentration contours

for carbon tetrachloride indicate a pot~ntial source area near monitoring well MW23-ST14 (carbon tetrachloride = 75 Ilg/L inCEI sampling). The Final CEI Addendum identifies the Northern Fire Department Wash Site as the source for carbon tetrachloride in groundwater at ST-14. The plume initially migrates eastward before assuming a northeasterly flow as it approaches the Cabin Branch tributary. Carbon tetrachloride was not detected in groundwater seep, surface water, or sediment samples during the CEI.

A second carbon tetrachloride plume was identified southeast of the Former East Side Gas Station, in the vicinity of MW31-ST14 (39 Ilg/L) and MW32-ST14 (22 Ilg/L). The source of this plume may have been carbon tetrachloride that was discarded after being used to clean auto parts at the gas station (Shaw, 2005). Carbon tetrachloride was not detected in soil samples collected in the • area. Groundwater in the second plume flows to the southeast. Carbon tetrachloride has not been detected in the nearby tributary of Cabin Branch.

Gasoline-related VOCs including benzene, toluene, ethylbenzene, tert-butyl benzene, chloromethane, ethylenedibromide, 1,2-DCA, and trimethylbenzene isomers have been detected in the plume in the vicinity of the Former East Side Gas Station. The SVOCs naphthalene and 2­ methylnaphthalene have also been detected in this area. Benzene is the predominant contaminant, with detections ofup to 20,000Ilg/L (see Figure 4.1). The benzene plume migrates eastward and northeastward towards the tributaries of Cabin' Branch. Benzene has been detected in seep locations along the banks of both tributaries. Direct-push sampling conducted in June 2006 did not identify' residual source area soils with benzene contamination.

Pesticides. Pesticides were detected in samples from 18 monitoring wells, but without any discernible pattern. All of the detections were at concentrations less than 1 Ilg/L. The pesticides identified in groundwater were: aldrin; lindane; alpha-, beta-, and delta-benzenehexachloride; • alpha- and gamma-chlordane; 4,4'-DDD; 4,4'-DDE; 4,4'-DDT; dieldrin; endosulfan I and II;

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Cadmium was detected in three samples at concentrations exceeding the MCL of 5 )lg/L. Thallium detections exceeded the MCL of 2 )lg/L in samples from 16 monitoring wells. Chromium exceeded the MCL in one sample at a concentration of 158 )lg/L in MWI0-ST14. The maximum detection of iron was 108,000 )lg/L in an unfiltered sample collected from MW04-ST14 ..Arsenic and antimony were both detected at concentrations below their respective MCLs.

4.2.3.2 Soil at Potential Groundwater Contaminant Source Areas I.

Three soil borings were completed at six separate potential source areas as part of the CEI and Supplemental CEL Based on the analysis of the samples collected from the six locations, soil containing VOCs, SVOCs, pesticides, and metals were reported. Only borings from the Former Aircraft Wash Rack and the Northern Fire Department Wash Site had contaminant concentrations that were consistent with past releases of chlorinated solvents. The contaminant concentrations in these two areas appear too low, however, to act as a continuing source for downgradient groundwater contamination.

Detected VOC soil concentrations were compared to USEPA Region III Soil Screening Levels (SSLs) and are discussed in the following paragraphs. The comparison aided in assessing the potential for soil to be a source for groundwater contamination. A dilution attenuation factor of 20 was used because of the anticipated small size of individual sources (less than 0.5 acres), as recommended by the USEPA Soil Screening Guidance (USEPA, 1996).

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Former East Side Gas Station. Petroleum-related VOCs~were detected in SB07-STl4, located in the vicinity of the former USTs, and photoionization detector (PID) screening results indicated that • most of the contaminated soil was located greater than 5 feet bgs. Benzene, m,p-xylene, and trimethylbenzenes exceed their SSLs in samples collected from approximately 4.5 to 6~0 feet bgs. However, the benzene concentrations are not consistent with the concentrations necessary to provide a source for the high levels of benzene detected in groundwater samples from MW 10- STl4.

Former Aircraft Wash Rack. TCE, 1,2-DCE, and several petroleum-related VOCs were detected in soil borings SB17-STl4 and SB18-ST14 at the Former Aircraft Wash Rack. Benzene and TCE exceeded their SSLs in samples taken from approximately 6.0 to 7.5 feet bgs (within a thin clay iayer). The concentrations of TCE (17 jJ.glkg max) and benzene (4.5 Ilglkg ~ax) are consistent with a release of TCE and fuel, but are not great enough to supply a continuing source for downgradient groundwater contamination. The soil screening level (SSL) exceedances were not statistically significant (2 exceedances in 6 samples collected) and do not indicate that soil contamination coul,d recontaminate the groundwater after completion of the remedy.

• Northern Fire Department Wash Site. Soil borings SB28-STl4, SB29~STl4, and SB30-STl4 were completed at the Northern Fire Department Wash Site. Three samples were collected from each boring. VOCs, SVOCs, pesticides, and metals were detected in samples collected from the borings.

Twenty-seven VOCs were detected in at least one of the subsurface soil samples collected from

SB30~ST14. The compounds with the highest detected concentrations were bromochloromethane (7,600 Ilg/kg); p-isopropyltoluene (3,500 Ilglkg); methylene chloride (280 Ilglkg); and dibromomethane (190 Ilglkg). Bromochloromethane and dibromomethane are compounds used in fire extinguishers. Methylene chloride and p-isopropyltoluene are solvents. The presence of these compounds in subsurface soil indicates that the area was used, for cleaning fire trucks and discharging fire extinguishers. ,

TCE was detected in the 9- to 1O-foot bgs interval of SB30~ST14 at a concentration of 3.2 Ilglkg,

exceeding the SSL of 0.26 Ilglkg. Methylene chloride and 1,4~dichlorobenzene also exceeded their SSLs in this sample. While uncertain, the source ofthese contaminants is most likely the historic • activities at this location. The SSL exceedances were not statistically significant and do not

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Above-background levels of barium, calcium, chromium, cobalt, copper, iron, lead, magnesium, manganese, molybdenum, nickel, potassium, sodium, vanadium, and zinc were observed in samples from the soil borings at the Northern Fire Department Wash Site. There is no apparent correlation between the elevated levels of metals and organic contamination, and the metals may be from non-native fill added during construction activities.

The analytical results of soil borings at .the Northern Fire Department Wash Site are consistent with a release ofsolvents. However, the detected concentrations are not considered significant enough to indicate existence of a continuing source for downgradientgroundwater contamination.

The low SSL exceedances were less than their applicable USEP A Region III Residential RBCs for • soils. Two of nine samples contained exceedances of the TCE SSL, while one of nine samples contained exceedances of the methylene chloride and l,4-dichlorobenzene SSLs. The exceedances were not statistically significant and do not indicate that soil contamination could recontaminate the groundwater after completion of the remedy.

4.2.3.3 Surface Soil

Near-surface soil sampling conducted during the CEI found several samples with low VOC, polyaromatic hydrocarbon (P AH), and pesticide concentrations. The concentrations encountered did not readily appear to be indicative of significant release or continuing source areas, but rather routine and non-localized ongoing Base operations and pesticide application.

During the CEI, surface soil was collected from eight locations and analyzed for VOCs, SVOCs, metals, and TOC. The locations were sampled again as part of the supplemental CEI activities and analyzed for pesticides. Low concentrations of up to five VOCs were present in all eight of the •

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initial samples. TCE and 1,1, I-trichloroethane were identified in one sample at concentrations of 3.6 and 0.87 !lgikg, respectively. One sample contained 11 PAHs and a second sample contained • seven. The other six samples did not contain any SVOCs. A total of 20 TALinorgartics were reported in the samples.

Ten pesticides were detected in the surface soil samples. Only one compound, dieldrin, exceeded its preliminary risk screening value. Dieldrin was detected at 190 !lgikg in SSOI-ST14. SSOI­

ST14, located on th~ northwest side of the Former East Side Gas Station, had the highest occurrence of pesticide detections ..

4.2.3.4 Surface Water and Sediment

Surface water and sediment samples collected from the Cabin Branch tributaries downstream of ST -14 contained TCE and DCE, indicating the edge of the groundwater plume had reached this boundary.

Five surface water and sediment sample pairs (SW/SE05-ST14 through SW/SE09-ST14) were • collected from the main tributary of Cabin Branch at the northern boundary of ST -14. Two sample pairs (SW/SE03-STI4 and SW/SE04-STI4) were collected from the minor (southern) tributary of Cabin Branch' that begins at Fetchet Avenue. The samples were analyzed for VOCs, SVOCs, and metals. Surface water samples were also analyzed for total dissolved solids and pH.

TCE was detected in surface water and sediment in two locations along the major tributary. TCE was detected at I!lglL at SW07-ST14, where the TCE and benzene plumes discharge to the creek. Cis-l,2-DCE and benzene were also detected in this sample at concentrations of 0.94 and 2.5 !lglL, respectively. TCE was also detected in surface water sample SW06-ST14 at a concentration of 0.56 !lg/L. The sediment sample containing the highest level of TCE (56 !lgikg), SE06-ST14, is located approximately 170 feet downstream from SW06-ST14. VOCs were not detected in the surface water and sediment samples collected from the mino!, (southern) tributary. Samples collected downstream from the point where the tributaries merge did not contain VOCs. One of the seven sediment samples contained SVOCs at concentrations that exceeded risk criteria. The presence of SVOCs in sediment was attributed to runoff from roads and parking lots.

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4.2.4 Initial Response Initial response at ST-14 consisted of the tank and associated soil removals listed in Subsection 4.1. • 4.2.5 Basis for Taking Action

The HHRA of the eEl Addendum determined that risks or hazards exceeded USEP A target levels for a future construction worker, future groundskeeper, future adult resident, and future child resident (Shaw, 2005). Exposure to shallow groundwater (especially TeE in groundwater) accounted for the majority of the risk or hazard posed to hypothetical receptors. The slight risk to a hypothetical future child resident from exposure to soil contaminants was assumed to be addressed through implementation of institutional controls, and no soil cleanup levels were established.

The HHRA included an evaluation of the vapor intrusion pathway for future residential receptors at ST-14 and concluded that potential cancer risks would exceed the USEPArisk management range 6 of 1x10-4 to 1x10- . The potential risks to current and future commercial workers at the site were not evaluated in the eEl Addendum.

The vapor intrusion exposure pathway for commercial workers in ST-14 buildings was subsequently evaluated in a supplemental risk assessment (Bhate Environmental Associates, Inc.) • which was appended to the FS report (Earth Tech, 2007a)_ The RME incremental lifetime cancer 6 risk for the commercial indoor air exposure pathway equaled to 9.3x10- , which does not exceed 6 the USEPA risk management range of 1x10-4 to 1xlO- _

The ROD concluded that response action was necessary to protect public health or- welfare from actual or threatened releases of pollutants or contaminants ·from ST -14 in groundwater and soil.

The site was not found to'pose an unacceptable ecological risk.

4.3 ST-14 REMEDIAL ACTIONS

The ROD for ST -14 was signed in September 2007 documenting the selected remedy for cleanup of groundwater and soil associated with known releases at the Site (USAF, 2007).

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4.3.1 Remedial Action Objectives

Based on anevaluatioti of site conditions, an understanding of the contaminants, the results of the • risk assessments, and an analysis of ARARs, the ROD identified the following RAOs for ST-14:

• Prevent the ingestion of shallow groundwater containing contaminants that exceed federal MCLs, non-zero maximum con~aminant levelgoals (MCLGs), or in their absence, an excess cancer risk of lx104 to lxlO-6 or a HQ of 1. • Prevent off-site migration of shallow groundwater with contamination above cleanup levels., • Restore shallow groundwater to expected beneficial uses to the extent practicable within a reasonable time frame. • Prevent residential exposure to soil. ' • Prevent residential and/or commercial exposure to groundwater contaminants ,at levels of ' concern via dermal contact, ingestion, or vapor intrusion.

COCs and cleanup concentrations as listed in the ROD are shown in the following table.

Contaminants of Concern and Cleanup Criteria at ST-14 Cleanup Criterion Contaniinant of Concern (/-lglL) Basis for Selection* Benzene 5 MCL Carbon tetrachloride 5 MCL Toluene 300 RBC • Trichloroethene 5 MCL Vinyl chloride 2 MCL Total xylenes 500 RBC *MCL = Federal drinking water Maximum Contaminant Level RBC = risk-based concentration (site-specific calculation)

It should be noted that MCLs were available during the determination of cleanup criteria for toluene and naphthalene, but that considerably lower risk-based values were used as cleanup criteria in the ROD (toluene 1,000 vs. 300 I-lg/L and total xylenes 10,000 vs. 500 I-lg/L). The derivation of the risk-based values is described in theFS report (Earth Tech, 2007a).

4.3.2 The Selected Remedy

The selected remedy at ST-14 was FS Alternative 4: Site-Wide Enhanced In-situ Biodegradation with Groundwater Monitoring and Institutional Controls. The remedy addresses groundwater contamination and potential future exposure to contaminated groundwater and soil. The major components of the selected remedy consist of the following:

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• Install organic carbon substrate injection points in the fonn of a barrier fonnation or • treatment zone perpendicular to groundwater flow in the TCE plume. • Install oxygen-releasing compound injection points in the fonn of a barrier fonnation or treatrnentzone perpendicular to groundwater flow in the benzene plume. . • Inject organic carbon substrate and oxygen-releasing compound. • Conduct groundwater monitoring to assess the effectiveness of the remedy, adjust re­ injection frequency and location, and monitor plume movement. • Re-inject organic carbon substrate and oxygen-releasing compound as needed. • Implement and maintain ICs in the fonn of groundwater use restrictions until cleanup criteria are met, and implement LUCs to prevent incompatible land use (residential). .

The FSestimated that Alternative 4 would require 20 to 30 years to achieve cleanup goals for COCs. this estimate was based on an aggressive injection program during the fIrst fIve years followed by routine monitoring and, if necessary, subsequent injections to continue the decline in chlorinated concentrations. This estimate does not take into account the precipitation and persistence of metals in the treated groundwater, as they were not anticipated to persist much longer than the COCs. No estimates were provided of interim contaminant reduction milestones .

4.3.2.1 Installation of Injection Points

As described in the ROD, full scale implementation of the selected remedy was anticipated to • require the direct-push installation of approximately 201 injection points for the treatment of the TCE and cOnimingled TCE! carbon tetrachloride plumes using organic carbon substrate, and 40 for . the treatment of the benzene plume. The points were to be constructed using I-inch diameter polyvinyl chloride casing with lO-foot, pre-packed wire screens and installed in staggered rows with approximately 25-foot spacing to fonn treatment barriers or zones situated perpendicular to groundwater flow .

4.3.2.2 Injection and Re-injection of Organic Carbon Substrate and Oxygen-Releasing Compound

Organic Carbon Substrate for TCE and Commingled Plumes. Upon the completion of the installation of injection points, an initial injection of organic carbon substrate is to be performed in the TeE and commingled TCE! carbon tetrachloride plumes. An oxygen-releasing compound is to be injected in the benzene plume.

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As described in the ROD, re-injection of organic carbon substrate will occur every eight weeks until anaerobic conditions are established. The re-injection frequency is subject to change based on • the results of monitoring. Post-injection performance monitoring will be used to confmn that the anaerobic reaction zone is fully established and that supplemental injections are not necessary across the length of each bio-barrier. The post-injection data will also be utilized to assess whether the injection frequency is sufficient to maintain the desired anaerobic reducing conditions. The criteria that will be used to determine when subsequent re-injections are necessary include:

• A TOC concentration of less than 50 mg/L for each mg/L of total chlorinated VOCs at monitoring wells within the anaerobic bio-reactive zones. • The ORP is greater than -50 millivolts (mY) (e.g., -37mV) at any monitoring point within the anaerobic bio-reactive zones.

The anaerobic bio-reactive zone is defmed as the areas within the radius of influence of each injection barrier or treatment zone.

Following the initial injections, field parameters including ORP, dissolved oxygen, pH, conductivity, and turbidity are to be measured on a monthly basis to verify the changes in geochemical conditions and confmn that conditions are conducive to dechlorination. The' field • parameters will be used as trigger indicators for establishing reducing conditions and determining the extent of the anaerobic bio-reactive zones. Based on the Pre-Design Study, it is estimated that it will take 6 months to establish reducing conditions in the injection areas. The presence of reducing conditions will be determined based on ORP, dissolved oxygen, and TOC. The optimal ORP is more negative than -50 m V (e.g., -105 m V). Dissolved oxygen concentrations should be less than 0.5 mg/L in the anaerobic areas. In order to optimize the degradation of chlorinated VOCs, the TOC concentration should be maintained at a minimum of 50 times the maximum total chlorinated VOC concentration. For example, a total chlorinated VOC concentration of 300 ).lg/L would require a minimum of 15,000 ).lg/L ofTOC.

Aft~r fully establishing the anaerobic reactive zones, a more extensive monitoring program is to be implemented involving existing and additional monitoring locations. If post-injection monitoring indicates that the anaerobic reactive barriers are not maintained, and TCE and its metabolites are not being reduced, additional or supplemental injections will' be proposed and implemented. The potential additional injections may also target the locations with insufficient delivery of organic

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The establishment of appropriate biochemical conditions for remediation will be demonstrated with the establishment .and maintenance of anaerobic reaction zones near and immediately downgradient of the injection points and the CVOC reduced concentration trends throughout the plume because of the organic substrates. •

Oxygen-Releasing Compound for Benzene Plume. Consistent with the proposed design of the aerobic and aerobic cometabolicbio-barriers for the BTEX and commingled BTEXITCE plumes, respectively, oxygen-releasing product injections are to be performed annually to enhance bioremediation of BTEX and TCE. Following each annual oxygen-releasing product injection and based on the post-injection monitoring results, if a statistically significant rebound in the BTEX (as detected by benzene·as indicator parameter) or TCE concentrations is observed, an assessment is to be performed to determine whether additional injections or other measures such as additional groundwater monitoring are warranted.

The· other criterion to be utilized to determine when subsequent or supplemental injections are warranted is the dissolved oxygen concentration. Dissolved oxygen concentrations are expected to be 3 to 5 mg/L at monitoring wells within the aerobic reactive zone or within 20 feet downgradient of injection locations during the monitoring event immediately following the injection. Note that subsequent utilization of dissolved oxygen and perhaps a return to sub-oxic or anaerobic conditions 76 • P:lProjects\Andrews AFB Environmental\Five-year reviews\4.0 _ Oeliverables\4.1_ ReportslFinal\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

following the initial event is, to a certain degree, to be expected and dissolved oxygen concentrations alone would not trigger an evaluation for further injections. Because anaerobic • biodegradation of these contaminants would continue, and, due to the relatively slow groundwater flow and low permeability of the formation, the dissolved contaminant plume is expected to . continue to be slow moving and continue to. degrade.

4.3.2.3 Environmental Monitoring

The activities to be performed under Alternative 4 also include groundwater monitoring (i.e., post­ injection groundwater sampling/analysis). In addition, CERCLA-mandated five-year reviews of the effectiveness of on-going remedies will be conducted and will serve as an additional opportunity to evaluate the effectiveness of the remedy. The objectives of the groundwater monitoring program associate.d with this alternative are to ensure that:

• Significant and measurable reductions in contaminant concentrations have occurred throughout the footprint of the commingled contaminant plumes when compared to baseline conditions. • The commingled contaminant plumes do not expand beyond the baseline footprint. • Contamination or injected sub'strates do not migrate off site andlor off Base. • Treatment of all COCs occUrs before the contaminated groundwater leaves the existing • footprint of the commingled contaminant plumes.

A monitoring network is to be utilized in the footprint of the contaminant plumes to ensure that favorable geochemical parameters for biodegradation of all COCs are maintained and to ensure that progress toward the cleanup criteria continues throughout the plume.

To determine that the treatment is operational and functional, trend analyses is to be performed using statistical methods and tools, andlor regression analyses will be performed in addition to the plume footprint evaluation.' The overall trend towards achievement of MCLs is expected to be asymptotic. It is anticipated that a significant decrease in COC concentrations will be achieved during the first five years of groundwater treatment. Thereafter, concentrations are expected to decrease, although not as rapidly since concentrations will be much lower. If the data indicate that

~he contaminant plumes are expanding beyond the baseline footprint, that decreasing trends in contaminants cannot be confirmed, andlor that achievement of MCLs is no longer anticipated within a 20- to 30-year timeframe, then re-injection of anyone or more of the following may be • 77 P:IProjects\Andrews AFB EnvironmentalIFive-year reviewsl4.0 _DeliverablesI4.1_ ReportslFinal\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011) required: substrate, buffer for pH adjustment, microorganisms or any other additive approved by the Joint Base Andrews partnership team, including USEPA, that will enhance the reduction of COCs at ST-14. Following completion of treatment, baseline (pre-treatment) geochemical • parameters will be restored in the aquifer for precipitation of metals (iron, arsenic,and manganese) that are liberated above initial pre-treatment concentrations as a result of the treatment of COCs.

The ROD anticipated that the groundwater monitoring program for this alternative will include quarterly groundwater monitoring for the first 18 months of the remedy implementation, semi­ annual monitoring for the second 18 months, and annual monitoring for years 4 through 30 or until the cleanup criteria are achieved. Samples will be analyzed for VOCs, metals, nitrate, sulfate, methane, ethane, ethene, alkalinity, and TOC. Samples will also be collected from select monitoring wells for microbial analysis to confirm the presence of reductive dechlorinating microorganisms. Additional monitoring locations may be installed if necessary. Field measurements will include temperature, conductivity, pH, ORP, and dissolved oxygen. Data collected will be used to demonstrate the actual trends in decreasing concentrations of COCs and to observe the generation of metabolites. The groundwater monitoring program will help determine if the treatment frequency is adequate and/or if additional treatment is warranted to attain the cleanup criteria in the 20- to 30-year tirneframe. • Monitoring data are to be used to perform a Mann-~endall statistical trend analysis using AFCEE's MAROS program (AFCEE, 2000). The Mann-Kendall Test will be used to evaluate whether contaminant concentrations at individual wells are stable, increasing, or decreasing and whether the Cleanup criteria will be achieved in the estimated 20- to 30-year timeframe.· The Mimn-Kendall Test requires a minimum of four data points. The initial analysis will be performed after 18 months of monitoring, using six data points generated by quarterly sampling.

The monitoring data and statistical trend analysis demonstrating the reduction of the COCs and their daughter compounds will also allow for targeting any potential additional treatments for specific· areas where levels of contamination may rebound or biological degradation is not suffIcient to achieve the cleanup criteria.

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4.3.2.4 Institutional Controls

Because the selected remedy for ST ':14 leaves contaminants in place at levels that do not allow • unlimited use and unrestricted exposure, the remedy includes ICs to ensure that the contaminants do not pose an unacceptable risk to human health or the environment during the time until cleanup criteria are attained. The general areas for which ICs are to be implemented are illustrated on Figure 4.1. The IC objectives are as follows:

• Ensure no use of groundwater, except for purposes of monitoring, until site conditions allow for unlimited use and unrestricted exposure. • Ensure no residential land use until site conditions allow for unlimited use and unrestricted exposure. • Ensure that construction activities on Base do not interfere with the remedy, including required monitoring, re-injection, treatments, or five-year review. • Ensure protection from contaminated subsurface soil and groundwater for all persons who access the site, including future maintenance and construction workers. • Ensure that any proposed changes in land use are consistent with protection goals. • Ensure that any groundwater extracted for purposes of monitoring that exceeds relevant regulatory criteria is handled in accordance with ARARs.

• The USAF is responsible for implementing ICs at ST-14. Under Alternative 4, the site is to have a LUC boundary identified in the Base GIS,as well as on hard copy maps of restoration sites. This designation prohibits activities such as residential development or potable use of groundwater. Additionally, groi.mdwater use is currently restricted, as documented in the BGP, and procedures are in place to limit contact with and ensure protection from groundwater through the issuance of dig permits and other protective measures (PBS&J, 2009). Records of the groundwater contamination will be kept in the Base GIS/environmental database. The restricted-use designation for groundwater will remain in place until groundwater monitoring indicates that the cleanup criteria have been met at ST-14.

The USAF will notify USEP A and MDE as soon as practicable, but no longer than 10 days after discoverY,of any activity that is inconsistent with the IC objectiyes or use restrictions, or any other action that may interfere with the effectiveness of the ICs. The USAF will notify USEPA and MDE regarding how the USAF has addressed or will address the breach within 10 days of sending USEPA and MDE notification ofthe breach.

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The USAF is to provide notice to USEP A and MDE at least 6 months prior to any transfer or sale

of ST-14 so that USEPA and MDE can. be involved in discussions to ensure that appropriate, provisions are included in the transfer terms or conveyance documents to maintain effective ICs. If • it is not possible for the facility to notify USEPA and MDE at least 6months prior to any transfer or sale, then USAF will notify USEPA and MDE as soon as possible, but no later than 60 days , prior to the transfer or sale of any property subject to ICs. In addition to the land transfer notice and discussion provisions above, the USAF further agrees to provide USEPAand MDE with similar notice, within the same timeframes,as to federal-to-federal transfer of property. The USAF shall provide a copy of the executed deed or transfer assembly to USEP A and MDE. The USAF shall not modify or terminate ICs, implementation actions, or modify land use without approval by USEPA and MDE. The USAF shall seek prior concurrence before any anticipated action that may disrupt the effectiveness of the ICs or any action that may alter or negate the need for ICs.

Other ICs proposed for ST -14 include the following:

.• Review and approval of any changes in land use, including construction of new facilities or additions to existing facilities at ST-14 by the Joint Base Andrews Facility Review Board, which interacts with the Community Planner using the BGP as a guide to land use issues. • Inclusion of the restrictions at ST-14 on the BGP. All ERP sites and restrictions at Joint Base Andrews are identified in the BGP. Any proposed. activity or construction on an • ERP site requires an "ERP Waiver to Construct" memorandum, approved and signed by USAF Headquarters Air Mobility Command. • Review of proposed construction activities at ST-14 by Joint Base Andrews Environmental Flight through the following processes: Environmental Impact Analysis Process (EIP A), NEPA Design Reviews of Proposed Construction, review of routine work orders that involve alterations to facilities, and review of dig permits. • Posting signs at the site identifying ST-14 as aCERCLA site. The signs will summarize the nature of contamination at the site and will state that no construction or excavation activities and no groundwater use or withdrawal is permitted within the area without written authorization by the USAF. Contact information for the ERP project manager will also be included on the signs. • Continued prohibition of potable use of groundwater. Potable use of groundwater is prohibited at ST-14 (and Joint Base Andrews, in general). Environmental personnel review of work orders and dig permits will also ensure that potable groundwater wells will not be installed at ST-14 .

. The ICs will remain in place until the concentration of hazardous substances at the site allows for unrestricted use and exposure. Monitoring of the environmental use restrictions and controls will 80 • P:\ProjectslAndrews AFB EnvironmentalIFive-year reviews\4.0 _ Deliverables\4. 1_ ReportslFinallAndrewsAFB _5-Yr Review _Revised March 201 I.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting. Inc. Project Number 3350092494 (Revised March 2011)

be conducted annually by Joint Base Andrews. The monitoring results will be included in a separate report or as a section of another environmental report, if appropriate, and provided to USEPA and MDE for informational purposes. The annual monitoring reports will be used in • . ,. preparation of the five-year review to evaluate the effectiveness of the remedy. The ICs can be modified as new data are analyzed. Joint Base Andrews shall notify USEP A and MDE 45 days in advance of any proposed land use changes that are inconsistent with LUC objectives or the selected remedy.

In .addition to these ICs, COMAR 26.03.0L05.A prohibits issuance of a permit to individual residents or businesses for private water supply wells when public water supplies are available; therefore, the installation of groundwater wells intended for potable use willnot be approved.

4.3.3 Remedy Implementation

Remedial actions were initiated at ST-14 in October 2007 (AECOM, 2009). Remedial construction included installation of 195 sodium lactate injection points and 28 temporary monitoring points to monitor the effects of the sodium lactate injections. Seven sodium lactate injection events were performed through June 2009 to address TCE and CT contamination in several specific areas throughout the site. In addition, one PermeOx® Plus injection event was completed in October • 2007 to address BTEX contamination. and stimulate cometabolic degradation of TCE in the 'northern portion of the site. . Supplemental injections for both lactate and PermeOx® were completed in July 2009. The ROD and Interim Remedial Action Completion Report (IRACR) each contain an estimate of 20 to 30 years to attain groundwater cleanup criteria.

Five quarterly groundwater sampling events were completed through April 2009 as part of the performance monitoring program.

4.3 4 System Operations/Operation and Maintenance

A Final Interim Remedial Action Completion Report has been completed for ST -14 to document , the completion of remedial activities required by the ROD (AECOM, 2009). Remedial system operation and maintenance beyond long-term monitoring is not scheduled; however, additional lactate and PermeOx® Plus injection may be required to maintainor stimulate biological degradation of contaminants.

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4.4 ST-14 PROGRESS SINCE LAST FIVE-YEAR REVIEW This is the fIrst fIve-year review for ST -14. • 4.5 ST-14FIVE.,;YEAR REVIEW PROCESS

.4.5.1 Community Involvement

The USAF has maintained a public involvement and infonnation program for the ERP since 1990 and maintains an Administrative Record as required by CERCLA. The Administrative Record is maintained at the Environmental Flight, 3466 North Carolina A venue, Joint Base Andrews. For the convenience of the public, a copy of the Administrative Record is maintained in an Infonnation Repository located at:

Prince George's County Memorial Library-Surratts-ClintonBranch 9400 Piscataway Road Clinton, MD 20735

Community involvement activities for this fIve-year review consisted of publishing a notice in two local newspapers announcing the USAF's intent to perfonn the fIve-year review and providing infonnation where and how the public could obtain additional infonnation. The notice appeared in • the Prince George's County Gazette on December 3, 2009, and in the Capital Flyer on December 18; 2009. A copy 6fthe notice is provided in Appendix A.

4.5.2 Document Review

The fIve-year review included review of relevant documents.including·the following:

•. Final Comprehensive Environmental Investigation Addendum, Site ST-14 (Shaw, 2005). • Final ST-14 Feasibility Study Report (Earth Tech, Inc., 2007a) • Final Record of Decision ST-14, Fonner East -Side Gas -Station (USAF, USEPA, and MDE,2007) • Final Site ST-14 Pre-Design Study Report, Evaluation of In-Situ Anaerobic Reductive Dechlorination of Chlorinated Contaminants in Groundwater (Earth Tech, Inc., 2007b) • Andrews Air Force Base General Plan Update, Land Use Control Implementation Plan, ST-i4 (USAF, 2008) • Report of Annual Land Use Control Monitoring, Andrews Air Force Base, Maryland, October 2007 - December 2008 (MACTEC, 2009)

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• Final Site ST-14 Interim Remedial Action Completion Report Environmental Remediation Activities, Phase II (AECOM, 2009) • General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland • (PBS&J,2009)

4;"5.3 Applicable or Relevant and Appropriate Requireinent Review

The ARARs presented in Appendix B of the ROD are reprinted and appended in Appendix D of this report. These standards and regulations were current at the signing of the ROD and as part of the five-year site review, have been reviewed for changes that could affect protectiveness. None of the ARARs listed in Appendix D have had changes since signing. of the ROD that affect the protectiveness of the implemented remedial action.

In addition, a search was performed for any newly promulgated standards which could affect protectiveness at the site. No new ARARs were identified that would affect the protectiveness of the remedy. Changes to ARARs and TBCs that pertain to risk assessment are discussed in Subsection 4.6.2.

• 4.5.4 Data Review

As part of the five-year review, groundwater monitoring data for TCE, carbon tetrachloride, benzene, toluene, and total xylenes were evaluated using the AFCEE's MAROS program. Data were evaluated for the period March 1, 2006, thro~gh October 2009, and included the fall 2009 sampling data (Table 4.1). These were the most recent data available at the time this report was drafted. In comparison, the data set in the TRACR did not include the fall 2009 data.

4.5.4.1 Trichloroethene

Of the 36 evaluated wells, 14 began and ended the evaluation period with TCE concentrations less

than the cleanup criterion of 5 ~g/L. These wells were MW03-ST14, MW03-347l, MW06-ST14, MW09-ST14, MW10-ST14, MWI8-ST14, MW20-ST14, MW21-ST14, MW22-ST14, MW25- ST14, MW26-STI4, MW29-ST14, MW30-ST14, and MW38-ST14. The Mann-Kendall- Test typically indicated no trend or stable conditions for these wells (Appendix D). Wells MW28-ST14 and MW36-ST14 had too few data points for statistical evaluation, but all available data values were less than the cleanup criterion. The 16 wells in this group were typically upgradient or downgradient of the of TCE plume areas, or near the former gas station where petroleum • 83 P:\ProjeC15\Andrews AFB Environmental\Five-year reviews\4.0_DeliverablesI4.I_Rep0l1s\Final\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

degradation had created conditions conducive to TCE reductive dechlorination. These wells are not well suited for evaluating the effectiveness of the remedy for TCE at the site. • Among the remammg wells, nine (MW08-ST14, MWll-ST14, MW13-ST14, MW15-ST14, MW17-ST14, MW19-ST14, MW23-ST14, MW27-ST14, and MW34-ST14) began the evaluation period with TCE concentrations greater than the cleanup criterion, but ended the evaluation period with concentrations less than or equal to the cleanup criterion. The Mann-Kendall Test typically indicated decreasing trends or stable conditions (MW27-ST14) for these wells. These wells are typically located close to, and downgradient of, lactate injection barriers. Reductions in TCE concentrations at the wells located immediately downgradient of injection barriers are attributed to TCE degradation within the biodegradation zones created by the barriers.

Thirteen wells have not attained the cleanup criterion (an improvement from the IRACR in which 15 wells had not attained the cleanup criterion). Of these thirteen, only three showed decreasing trends, and four showed increasing or probably increasing trends. It should be noted, however, that while the Mann-Kendall Test shows long-term (March 2006 to October 2009) probable increasing TCE concentrations at MW05-ST14, recent data (October 2008 to October 2009) show a decreasing trend. Overall, the results are similar to those in the lRACR. The results of the Mann­ Kendall Test for these wells are shown in the following table. •

Summary of Mann-Kendall Statistical Analysis - TCE in ST-14 Wells Concentration (I-lglL) Mann-Kendall Monitoring Well March 2006/0ct.2009 Statistic Mann-Kendall Trend MW24-STl4 64118 -28 D MWI2-ST14 1180/182 -25 D MW33-STl4 32/16 -18 D MWI6-STl4 65/65 -2 S MWOl-ST14 75/30 2 NT MW04-STl4 64/187 2 NT MW07-STl4 71/36 * 6 NT MW02-STl4 4.4/33 10 NT MW35-STl4 1/7.4 10 NT MW05-STl4 11128 16 PI MW31-STl4 0.6/18 16 I MW32-STl4 165/733 17 I MW37-ST14 475/1020 24 I Notes: D = decreasing trend, NT = no trend, I = increasing trend, PI = probably increasing trend, S = stable * decreasing last four samples.

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Several of these wells are also located close to, and downgradient of, lactate injection barriers, and • while some show decreasing concentrations as a result of lactate injection, others do not. Following a detailed review of analytical data through April 2009 and groundwater flow patterns, the remedial contractor identified two TCE hot spots, and additional lactate was .injected in July 2009 in the vicinity of MW37-ST14 and MW07-ST141MW32-ST14 (AECOM, 2009). The October 2009 data showed a TCE decrease at MW07-ST14 (from 825 IlglL in January 2009 to 36 IlglL), but little change at MW32-STI4 (752 to 733 IlglL) and MW37-ST14 (908 to 1020 IlglL) over the same time period. Additional, time may be needed for the effects of the additional injections to become evident.

For wells MW12-ST14, MW16-ST14, MW24-ST14, and MW33-ST14 which were characterized as decreasing or stable according to the Mann-Kendall Test, linear regression of the concentration data was used to determine the exponential curve fit and estimate the length of time until the cleanup criterion will be achieved at those locations. Plots of the data are shown in Appendix D. Estimated times to attain the TCE cleanup criterion are tabulated in the following table. (MW 16- ST14 is not included because the regression plot did not show..a decreasing trend.)

Results ofRegression Analysis' for TCE at Selected Wells • Years to Attain Well Starting concentration Cleanup Criterion * Attainment Date * MWI2-STl4 1180 4.0 September 2011 MW24-STl4 64 5.0 September 2012 MW33-STl4 32 7.3 December 2014 * Based on initial injection date of October 2007

It must be emphasized that the estimated times are only for the three wells with decreasing trends with the assumption that geochemical conditions will remain favorable for degradation at current rates: Wells with no trend/stable trend/or increasing trend are expected to take longer.

Data for selected monitoring wells were reviewed, however, to see if DCE was accumulating, as that could be indicative of stalled reductive dechlorination. This can be a problem because 1) DCE can present exposure risks if its concentrations become great enough, and 2) the DCE may be slow to degrade. During reductive dechlorination, TCE is degraded to DCE, which is then degraded to

vinyl chloride~ The vinyl chloride is then degraded to ethene. Concentrations of DCE may increase temporarily, but should then decrease. The total molar concentration of TCE and daughter • 85 P:\Projects\Andrews AFB Environmental\Five-year reviewsl4.0 _DeJiverablesI4.1_ReportsIFinal\AndrewsAFB _5-Yr Review_Revised March 2011.doc JointBase Andre'ws - First Five- Year Review November 20iO MACTEC Engineering and Consulting, inc. Project Number 3350092494 (Revised March 201 i)

products should also decrease. If conditions are not conducive to complete dechlorination, TCE will degrade to DCE, but the DCE does not degrade (or degrades only slowly) and accuI?ulates. • Review of the data in Table 4. 1 shows several instances where reductive dechlorination may have

stalled. At monitoring wells MWll~ST14, MW13-STI4, MW15-ST14, MWI7-ST14, MW19- ST14, and MW34-ST14, TCE concentrations have decreased to cleanup criterion levels, while DCE has increased to concentrations exceeding its MCL of 70 /J.g/L. (There was no cleanup criterion established in the ROD for DCE.) To better understand the status of the cleanup, illustrative data plots were prepared for the above monitoring wells and are included in Appendix D.

To prepare the plots, TCE, DCE, and vinyl chloride concentrations for selected monitoring wells were tabulated for the period from March 2006 (representing baseline conditions) through October 2009. The mass concentrations for individual compounds were converted to molar concentrations. The molar concentrations of TCE, cis/trans-DCE, and vinyl chloride as well.as their sum were then plotted as time series data. Instances in which TCE decreased to low concentrations and DCE increased to approximate a non -declining (or very slowly declining) total were considered to represent stalled degradation conditions. In each case, degradation of DCE has become the rate determining step in groundwater cleanup. r •

The data indicate limited generation and accumulation of vinyl chloride (cleanup criterion = 2 /J.g/L), but it does not appear to be a rate limiting step.

4.5.4.2 Carbon Tetrachloride

Of the 36 evaluated wells, 35 had concentrations of carbon tetrachloride less than the cleanup criterion of 5 /J.glL in the October 2009 sampling. The MAROS program characterized the one well (MWOl-ST14) not attaining the cleanup criterion as having no trend according to the Mann­ Kendall Test. Concentrations at MWOl-ST14 have ranged from 7.2 to 4.6 /J.g/L during the last eight sampling events. MWOl-ST14 is approximately 700 feet downgradient of lactate Injection Barrier 7, and probably has not been significantly influenced by injections there. It is unclear how long will be required to reach the cleanup criterion.

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4.5.4.3 Benzene

Of the 36 monitoring wells evaluated for benzene concentration, 30 had concentrations less than • the cleanup criterion of 5 IlglL. It should be noted, however, that most of these wells are not located in an area where benzene is a concern. Wells where benzene is an historical concern include MW02-ST14, MW03-ST14, MW04-ST14, MW05-ST14,and MWI0-ST14, all in the vicinity of the former gas station, and MW03-3471 located near the western edge of the site. Of these wells, none have attained the cleanup criterion, and only two, MW03-ST14 and MW04- ST14, show decreasing trends according to the Mann-Kendall Test.

The results of the Mann-Kendall Test for these wells are shown in the following table.

Summary of Mann-Kendall Statistical Analysis - Benzene in ST-14 Wells Concentration (p.1g1L) Mann-Kendall Monitorin2 Well March 2006/0ct. 2009 Statistic Mann-Kendall Trend MW03-ST14 154/38 -34 D MW04-ST14 837/428 -28 D MWI0-ST14 6030/211 -10 S MW05-ST14 45/35 -4 S MW02-ST14 22/204 8 NT MW03-3471 15/54 10 NT Notes: • D = decreasing trend, NT = no trend, I = increasing trend, PI = probably increasing trend, S = stable Based on previous review of concentration trends, the remediation contractor identified areas near MW04-ST14 and MWI0-STI4 for supplemental PermeOx® Plus injections. These injections were completed in July 2009. It is unclear if the decrease in concentrations at MW04-STI4 was the result of the supplemental PermeOx® Plus injections or a continuation of an existing trend. Benzene concentrations at MWI0-ST14 decreased substantially between July 2009 (2,940 IlglL) and October 2009(210 IlglL) and may have been influenced by the supplemental PermeOx® Plus injections.

For the wells where benzene was characterized as decreasing or stable according to the Mann­ Kendall Test, linear regression of the concentration data was used to determine the exponential curve fit and estimate the length of time until the cleanup criterion will be achieved at those locations. Plots of the data are shown in Appendix D. Estimated times to attain the benzene cleanup criterion are tabulated inthe followmg table.

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Results of Regression Analysis for Benzene Years to Attain Well Starting Concentration Cleanup Criterion * Attainment Date * MW03-STl4 154 4.7 May 2012 MW04"STl4 837 6.5 March 2014 • MW05-STl4 45 10.7 May 2018 MWIO-STl4 6030 4.4 February 2012 * Based on initial injection date of October 2007

It' must be emphasized that the estimated times are only for these four wells with the assumption that geochemical conditions remain favorable for degradation at current rates. Wells with no trend/stable trend/or increasing trend are expected to take longer.

4.5.4.4 Toluene

Of the 36 monitoring wells evaluated for toluene concentration, 34 had concentrations less than the cleanup criterion of 300 IlglL.1t should be noted, however, that most of these wells are not located in an area where toluene was a concern ..Only two wells, MW04-STl4 and MW10-STl4, have historical exceedances of the toluene cleanup criterion. At MW04-STl4, toluene decreased from 4,070 to 1,870 IlglL between February/March 2006 and October 2009. At MW 1O-STl4, toluene concentrations decreased from 37,800 to 792 IlglL over the same period. The MAROS program • characterized MW04-ST-14 as having a decreasing trend, and, because of fluctuating concentrations, MW10-STI4 as having no trend. The MAROS results are summarized in the following table.

Summary of Mann-Kendall Statistical Analysis - Toluene in ST-14 Wells Concentration (/-lg!L) Mann-Kendall Monitorin2 Well March 2006/0ct. 2009 Statistic Mann-Kendall Trend MW04-STl4 4070/1870 -20 D MWIO-STl4 378001792 -8 NT Notes: D = decreasing trend, NT = no trend, I = increasing trend, PI = probably increasing trend, S = stable

Based on previous review of concentration trends, the remediation contractor identified areas near MW04-ST14 and MWIO-ST14 for supplemental PermeOx® Plus injections. These injections were completed in July 2009. It is unclear if the decrease in concentrations at MW04-STI4 was the result of the supplemental PermeOx® Plus injections or a continuation of an existing trend. Toluene concentrations at MWIO-STl4 decreased substantially between July 2009 (20;700 IlglL) and October 2009 (792 IlglL) and may have been influenced by the supplemental PermeOx® Plus injections. 88 • P:IProjectslAndrews AFB EnvironmentallFive-year reviewsI4.0_DeliverablesI4.1_ ReportslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five- Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011) e For MW04-ST14, where toluene was characterized as decreasing according to the Mann-Kendall Test, linear regression of the concentration data was used to determine the exponential curve fit and estimate the length of time until the MeL will be achieved at that location.

Results of Regression Analysis for Toluene Years to Attain Well Startin2 concentration Cleanup Criterion Attainment Date * MW04-ST14 4070 5.9 August 2012 *Based in initial injection date of October 2007

It must be emphasized that the estimated times are only for this well with the assumption that geochemical conditions remain favorable for degradation at current rates. Wells with no trend/stable trend/or increasing trend are expected to take longer.

4.5.4.5 Total Xylenes

Of the 36 monitoring wells evaluated for total xylenes concentration, 35 had concentrations less than the of 500 IlglL in October. 2009 samples. It should be noted, however, that most of these wells are not located in an area wherexylenes were a concern. Only two wells, MW04-ST14 and MW 1O-ST14, have ·historical exceedances of the total xylenes cleanup criterion. At MW04-ST14, total xylenes decreased from 3,470 to 2,259 IlglL between February/March 2006 and October 2009. At MW10-ST14, total xylenes concentrations decreased from 12,850 to 496 IlglL over the same period. The MAROS program characterized MW04-ST-14 as having stable concentrations and MWIO-ST14 as a having a probable decreasing trend according to the Mann-Kendall Test.

Based on previous review of concentration trends, the remediation contractor identified areas near MW04-ST14 and .MWI0-ST14 for supplemental PermeOx® Plus injections. These injections were completed in July 2009. It is unclear if the decrease in concentrations at MW04-ST14 was the result of the supplemental PermeOx® Plus injections or a continuation of an existing trend. Total xylenes concentrations at MWI0-ST14 decreased substantially between July 2009 (8,610 Ilg/L) and October 2009 (496IlglL) and may have been influenced by the supplemental PermeOx® Plus injections. e· 89 P:\ProjectsIAndrews AFB EnvironmentallFive-year reviewsl4.0 _ DeliverablesI4.1_ ReportslFinallAndrewsAFB _5-Yr Review_Revised March 201l.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

For MW04-ST14 and MW10-ST14, linear regression of the concentration data was used to determine the exponential curve fit and estimate the length of time until the MCL will be achieved at those locations. •

Results of Regression Analysis for Total Xylenes Years to Attain Well Starting concentration Cleanup Criterion Attainment Date * MW04-STl4 3470 8.9 August 2015 MWIO-STl4 12850 4.6 April 2012 * Based in initial injection date of October 2007

4.5.4.6 Vinyl Chloride

Of the 36 monitoring wells evaluated for vinyl chloride, 34 had concentrations less than either the reporting limit or the cleanup criterion in their most recent (October 2009) sample, and 33 had concentrations less than either the reporting limit or the cleanup criterion in all four of the 2009 quarterly samples. Samples from three monitoring wells had vinyl chloride concentrations greater than the cleanup criterion at least twice in 2009. At MW11-ST14, vinyl chloride concentrations showed an increasing trend from 1.1 to 16.9 ·llglL between January 2008 and October 2009, coincident with a TCE decrease from 145 to less than 1 IlglL. At MW17-ST14, vinyl chloride concentrations increased from 2.2 to 3.6 IlglL between March 2006 and April 2009, and decreased to less than reporting limits in October 2009, coincident with a decrease in TCE from 1,240 IlglL to • less than reporting limits. There was no clear overall trend. At MW37-STl4, vinyl chloride concentrations varied between 2.0 and 8.5 IlglL between March 2006 and October 2009, and decreased slightly after that without a clear trend.

Under conditions of reductive dechlorination such as those at ST -14, TCE breaks down into DCE, vinyl chloride, and ultimately non-chlorinated end products. During this process, vinyl chloride concentrations can, and often do, increase temporarily as reductive dechlorination of TCE imd DCE occurs. The elevated vinyl chloride concentrations at MW11-ST14, MW17-ST14, and MW37- ST14 are indicative of the reductive dechlorination ofTCE and DCE and may remain elevated until degradation of TCE and DCE is complete. They are expected to return to levels less than· the cleanup criterion after degradation of TCE and DCE is complete. The increasing or unclear concentration trends for these three wells cannot be used to estimate a cleanup time. As noted above,however, the concentration of vinyl chloride in 34 of 36 monitoring wells was less than the cleanup criterion. Vinyl chloride concentrations will continue to be monitored for attenuation as

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part ofthe ongoing long tenn monitoring program at ST-14 during the timeframe required to attain • site cleanup levels. 4.5.5 Site Inspection

A LUC inspection was perfonned at ST-14 in January 2009 as part of a comprehensive LUC inspection at Joint Base Andrews CERCLA sites with RODs (MACTEC, 2009b). The ST-14 site was viewed on October 21, 2009. The inspection confirmed general site conditions and land use assumptions.

4.5.6 Interviews

No interviews were conducted with community members in regard to ST-14. A pup1ic notice was published in two area newspapers in December 2009, indicating that the review process was underway and providing contact infonnation for questions or comments. No inquiries from the general public were received. Input on the review process was obtained from representatives of the USEPA, MDE, and Prince George's County through their participation in the Tier 1 partnering team and by their review of preliminary drafts of this document.

• 4.6 ST-14 TECHNICAL ASSESSMENT

4.6.1 Question A: Is the remedy functioning as intended by the decision documents?

Yes, the remedy is functioning as intended by the ROD, as discussed further below.

Implementation of Institutional Controls and Other Measures. The Joint Base Andrews Environmental Flight developed a draft LUCIP for the ST-14 site in April 2008 (USAF, 2008. The LUCIP presents spec'ifIc requirements for the establishment, implementation, and maintenance of LUCs at ST -14. When fmalized, the LUCIP will be provided to the Joint Base Andrews Community Planner so that its requirements can be incorporated into the BGP. It is noted, however, that the BGP identifies' ST-14 as an active ERP site (PBS&J, 2009). Therefore, a Waiver-to-Construct is required for all proposed construction on an ERP site (API 32-1021). A Waiver-to-Construct means the proposed construction has been evaluated with respect to site activity and environmental risks proposed by the construction and ultimate use of the facility. The BGP contains a listing of ERP sites as well as a map showing their locations (PBS&J, 2009).

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In addition, groundwater is prohibited from being used for potable purposes anywhere on Base (PBS&J, 2009), and COMAR 26.03.01.05 prohibits installation of new water supply wells . . Joint Base Andrews has posted signs at ST -14 to indicate that groundwater at the site presents a • potential hazard and that construction, excavation, and groundwater use are prohibited (MACTEC, 2009).

Electronic map layers showing the locations of restricted areas associated with ERP sites have been posted on the official Joint Base Andrews GIS (AndrewsAFB Geo-Base) to assist all organizations with project planning and design tasks (MACTEC, 2009).

Annual LUC monitoring was completed and reported for the period October 2007 through December 2008 (MACTEC, 2009). The report concluded that all required LUCs have been implemented for ST -14. The report did not identify inconsistent uses or LUC deficiencies, or

I activities that could interfere with the effectiveness of the land use restrictions and controls. The report for 2009 was being prepared at the time of this five-year review.

Remedial Action Performance. Data to date indicate that the remedial action has created conditions conducive to reductive dechlorination of TCE and carbon tetrachloride at the lactate • injection barriers. Further, TCE concentrations have decreased to less than the cleanup criterion at several monitoring wells, and concentrations are decreasing at three additional wells. However, at 10 wells TCE concentrations do not show a statistically decreasing trend and, in fact, concentration trends are increasing at 3, possibly 4, wells. Following an extensive review of analytical data and geochemical data through April 2009 and groundwater flow patterns, supplemental lactate injections were completed at three hot-spot areas (i.e., near wells MW07-ST14, MW32-ST14, and MW37-ST14) in July 2009 where TCE concentrations remained high and conditions favorable to reductive dechlorination (i.e., low ORP and dissolved oxygen) had not been established. At MW07-ST14 TCE concentrations now appear to be decreasing, while at MW32-ST14 and MW37- ST14, ORP and dissolved oxygen are decreasing, but TCE concentrations remain high. At MW37- ST14, October 2009 data showed little effect from the supplemental injections. Additional time and possibly additional lactate injection will be necessary before TCE cleanup criterion are met at these and remaining locations. Subsection 4.5.4.l discussed the potential stalling of reductive dechlorination after degradation ofTCE based on the review of data from several monitoring wells .

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One well still slightly exceeds the cleanup criterion for carbon tetrachloride (5.8 vs. 5 ~glL). This well is considerably downgradient of the lactate injection barriers, and future reductions in carbon • tetrachloride may depend upon natural attenuation. None of the wells in which benzene historically exceeded the cleanup criterion have attained the cleanup criterion, although two show decreasing trends according to the Mann-Kendall Test. Following an extensive review of analytical data and geochemical data through April 2009 and groundwater flow patterns, supplemental PermeOx® Plus injections were completed at two hot­ spot areas (i.e., near wells MW04-ST14 and MWIO-ST14) in July 2009 where benzene concentrations remained particularly high. Little apparent concentration reduction was observed in

the October 2009 sample from MW04-ST14 (i.e., benzene levels dropped from 441 to 428 ~glL).

In contrast, concentrations in MW 10-ST14 dropped 93 percent (from 2,490 to 211' ~glL) between July and October 2009. Additional time and possibly additional PermeOx® Plus (or similar material) injection will be necessary before the benzene cleanup criterion is met at these and remaining locations.

Concentrations of toluene and total xylenes are decreasing at the two wells where they were a concern.

• System Operations/Operation and Maintenance. The remedial approach does not require routine operation and maintenance. Groundwater monitoring is required, however, to assess progress at meeting cleanup criteria, and additional injection of lactate may be necessary to maintain TCE degradation, and additional PermeOx® Plus injections may be necessary to maintain treatment of benzene, toluene, and total xylenes. Groundwater monitoring is presently being performed quarterly.

Cost of System Operations/Operation and Maintenance. Estimated and actual costs for RA-O are shown in the following table. As is shown, actual costs are exceeding estimates and reflect greater levels of monitoring than expected.

ST-14 Annual System Operations, Monitoring, and Maintenance Costs Calendar' Year Year Estimated Cost1 Current/Actual Cost Description 1 2006 $62,000 2 2007 $115,000 3 2008 $38,000 $200,000 RA-O 4 2009 $24,000 $200,000 RA-O • 93 P:IProjects\Andrews AFB EnvironmentallFive-year reviewsI4.0_DeliverablesI4.1_ReportslFinaJ\AndrewsAFB_5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering andConsuiting. Inc. Project Number 3350092494 (Revised March 2011)

Notes: The initial injections of sodium lactate and ORC® substrates occurred in May 2006. Operations, monitoring and maintenance costs have been assumed to begin in 2006. I Estimated costs derived from ST-14 Final Feasibility Study Table 4-13 • Expected Progress Towards Meeting RAOs. See Remedial Action Performance above.

4.6.2 Question B: Are the exposure assumptions, toxicity data, cleanup levels, and RAOs. used at the time of the remedy still valid?

Yes, the exposure assumptions, toxicity data, cleanup levels and RAOs remain valid.

Changes in Standards and To Be Considered Values. This five-year review did not identify ARARs that have been promulgated since the ROD was signed.

Changes in Exposure Pathways. No changes iIi current or reasonably foreseeable future site conditions that affect exposure pathways were identified as part of this five-year review. The groundwater in the shallow aquifer where ST -14-related contamination was detected is not used as \ a potable or industrial water resource. The groundwater at ST-14 is not used currently for drinking, washing, or industrial uses because the Base is served by the WSSC public water supply. In addition, surface water in the segment of Cabin Branch affected by ST~14 is not conducive to • supporting aquatic communities. No· changes to the use of groundwater on Base, or supply of public water to the Base, are anticipated. Nonetheless, groundwater is considered a natural resource under the Maryland Anti-Degradation Policy (COMAR 26.08.02.04), and must be maintained as a potential source of drinking water. Consequentlr, the RAOs stipulated in the ROD, to restore shallow groundwater to expected beneficial uses to the extent practicable, are unchanged by land uses or exposure pathways.

Changes in Risk Assessment Methodology, Toxicity, and Other Contaminant Characteristics., The baseline risk assessment for ST -14 identified COPCs for exposures to surface soil, subsurface soil, groundwater and surface water in the stream.

Five COPCs were noted for surface soil, none of which was identified as a COC requiring remediation. Six COPCs were noted for surface soil vapors or suspended particulates, and none of these was identified as a COC requiring remediation.

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Sixteen COPCs were noted for combined surface and subsurface soil, none of which was identified as a COC requiring remediation. Nine COPCs were noted for combined surface and subsurface • soil. vapors or suspended particulates, none of which was identified as a . COC requiring remediation.

Forty-six COPCs were noted for groundwater, of which five (benzene, carbon tetrachloride, TCE, toluene, and vinyl chloride) were identified as COCs requiring remediation. Twenty.;five COPCs were identified for vapors of groundwater origin, one (m,p-xylene) of which was identified asa coe requiring remediation. Two COPCs were noted for sediment and threeCOPCs were noted for surface water, neither of which was identified as a COC requiring remediation. The COPCs that were not identified as COCs that required remediation were established as such because they did not contribute significantly to risks.

The toxicity values for the COPCs and COCs were reviewed to determine if any changes (updates) to toxicity values could change the COCs that were identified as chemicals requiring remediation.

Of the COPCs identified in ST-14 soil, sediment, groundwater, and surface .water, toxicity values selected in accordance withtheUSEPA policy on human health toxicity values in Superfund risk assessments (USEPA, 2003) have been updated as shown in Table 4.2.

Collectively, none of the updated toxicity values or draft proposed updated toxicity values would change the conclusions ofthe risk assessment or selection of COCs requiring remedIation.

Implications on Cleanup Levels. The groundwater cleanup levels for the· COCs were based on. the USEPA MCLs for benzene (5)lg/L), carbon tetrachloride (5)lg/L), TCE (5)lg/L),and vinyl chloride (2 )lg/L). Cleanup levels for toluene (300 )lg/L) and total xylenes (500 )lg/L) were based on site-specific risk-based calculations. None of the identified changes in exposure pathways, risk assessment methodology, or toxicity values would change the cleanup levels or call into question the protectiveness of the remedy .

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4.6.3 Question C: Has any other information come to light that could call into question the • protectiveness of the remedy?

No other information has come to light that calls into question the short-term protectiveness of the remedy.

4.6.4 Technical Assessment Summary

Aggressive injection of treatment reagents over a two year period has had observable results, particularly on TCE where nine of 22 wells that previously exceeded the cleanup criterion for TCE have now declined to levels below the cleanup criterion. Still, there are a substantial number of wells where concentrations of COCs remain above cleanup criterion and significant downward trends are not yet apparent. This is in part attributable to the fact that the estimated time frame for cleanup is 20 to 30 years, and insufficient time has passed to allow attainment of the cleanup criterion. However, it also appears reflective of subsurface heterogeneities that result in unexpected groundwater flow patterns and unexpected distribution of lactate.. . Supplemental groundwater surface mapping in 2009 resulted in revision of interpreted groundwater flow paths.

Non~decreasing concentrations of contaminants in groundwater may also reflect the presence of high concentration areas that are more difficult to treat. • The interpreted groundwater elevation contours oil. Figure 4~11 of the IRACR do not appear to consider the potential effect of the Charles Branch tributary directly east of Pennsylvania A venue on groundwater flow patterns and contaminant migration. In addition, no monitoring wells are indicated in this area from which to obtain data to confirm the interpreted flow patterns. Additional monitoring points in this area would help in' confirming groundwater flow and contaminant migration pathways.

Based on the interpreted groundwater flow patterns in the IRACR, there may be a gap in monitoring well coverage downgradient of MW04-ST14 (i.e., east or east~northeast of MW04- ST14 and between MW04-ST14 and the Cabin Branch tributary). Further, it is likely that the TCE plume extends from TMP04 to MWOl-ST14 and TMP02. In addition, many of the monitoring wells used to assess remedy effectiveness are in close proximity to the lactate injection barriers and may not be well-located to measure conditions groundwater approaching the barriers.

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The remediation contractor has monitored remedy performance with an extensive array of permanent monitoring wells and temporary monitoring points, and has followed up with • supplemental injection of ·lactate for TCE treatment and PermeOx® Plus injections for benzene/petroleu~ treatment (AECOM, 2009). Additional monitoring and time are necessary to assess the effectiveness of the supplemental injections.

In the case of TCE, review of the data shows that the wells that have not attained the TCE cleanup criterion typically do not show the negative ORP conditions needed for degradation of TCE. If ORP .does not drop to appropriately low levels in the near future, additional organic substrate injections (e.g., lactate injections) may be needed. mthe case of benzene, review of the data shows that dissolved oxygen concentrations near zero are often associated with slowed reductions in benzene, while high dissolved oxygen concentrations are often associated with accelerated benzene reduction (e.g., a very high dissolved oxygen concentration at MW 1O-ST14 in October 2009 corresponds to a marked drop in benzene compared to previous samples). Additional time is needed to assess how effective recent PermeOx® Plus mjeciions will be at increasing dissolved . . . oxygen. Additional PermeOx® Plus injections (or similar oxygen releasing compound) may be required. • There have been no changes in site conditions that affect protectiveness. There have been no changes to toxicity factors for COCs or changes to risk assessment methodology that would change the protectiveness of the remedy. There is no information that calls irito question the short-term . , protectiveness of the remedy.

4.7 ST-14 ISSUES

The following table summarizes the issues identified or Site ST-14 during this five-year review. The table only lists issues that affect current and/or future protectiveness.

Affects Protectiveness Issues (yIN) Current Future

There may be gaps in monitoring well coverage northeast of MW04-ST14 N Y and southeast ofMW37-ST14.

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4.8 ST-14 RECOMMENDATIONS AND FOLLOW-UP ACTIONS

The following table summarizes recorru:ilendations and follow-up actions identified for Site 8T-14 during this five-year review. The table only lists recommendations and follow-up actions for issues • that affect current and/or future protectiveness.

Follow-up Action Affects Recommendations / Follow-up Party Oversight Milestone Protectiveness Actions Responsible Agency Date (YIN) Current Future Perform investigation to assess whether unmonitored contaminant migration pathways exist . USAF USEPA 12/3112011 N Y northeast of MW04-ST14 and southeast ofMW37-ST14.

4.9 ST-14 PROTECTIVENESS STATEMENT

The selected remedy for ST.:14 is expected to be protective of human health and the environment upon completion, and, in the interim, exposure pathways that could result inu.nacceptable risks are being controlled. The installation of additional monitoring wells and continued sampling and analyses will be used to evaluate the performance ofthe remedy in the short and .long-term. The • installation of these monitoring wells will be used to determine if additional injections are necessary in accordance with the ROD or if additional remedial measures are necessary.

4.10 ST-14 NEXT REVIEW

ST -14 is a statutory site that requires ongomg five-year reviews. The next reVIew will be performed within five years of the completion of this five-year review report. The completion date

is the date of the signature shown on the signature cover attached~!o the front of this report.

4.11 ST-14 REFERENCES

AECOM, 2009. Final Site ST-14 Interim Remedial Action Completion Report Environmental Remediation Activities, Phase II, Andrews Air Force Base, Camp Springs, Maryland, December.

Dames & Moore, Inc., 1992. Groundwater Contamination Survey, Andrews Air Force Base, Maryland, prepared for Hazardous Waste Remedial Actions Program, Oak Ridge,. Tennessee. 98

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Dames & Moore, Inc., 1994. Final Technical Memorandum of Findings, Site ST08 Investigation, . Andrews Air Force Base, Maryland, prepared for Hazardous Waste Remedial Actions • Program, Oak Ridge, Tennessee, November. . Earth Tech, Inc., 2007a. Final ST-14 Feasibility Study Report, Environmental Restoration Program, Andrews Air Force Base, Maryland, January.

Earth Tech, Inc., 2007b. Final Site ST-14 Pre-Design Study Report, Evaluation of In-Situ Anaerobic Reductive Dechlorination of Chlorinated Contaminants in Groundwater. Andrews Air Force Base, Maryland, June

ES (Engineering-Science), 1985. Installation Restoration Program, Phase I Records Search, Andrews Air Force Base, Maryland, prepared for USAF AFESCIDEV, Tyndall AFB, Florida, and USAF HQ MACIDEEV, Scott AFB, Illinois.

IT Corporation, 1995. Long-Term Monitoring Report, Second-Round Groundwater Sampling, Command Underground Storage Tank Investigation, Andrews Air Force Base, Maryland, prepared for Tennessee Center for Research and Development, Knoxville, Tennessee.

IT Corporation, 2000. Final Comprehensive Environmental Investigation, Site ST -14, Andrews Air Force Base, Maryland, prepared for Air Force Center for Environmental Excellence, Brooks Air Force Base, Texas,December.

PBS&J, 2009. General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland, December.

MACTEC, 2009. Report of Annual Land Use Control Monitoring, Andrews Air Force Base, • Maryland, October 2007 -.:... December 2008, February.

Shaw Environmental, Inc., 2005. Final Comprehensive Environmental Investigation Addendum, Site ST-14, Andrews Air Force Base, Maryland, prepared for Air Force Center for Environmental Excellence, Brooks Air Force Base, Texas, November.

USAF, USEPA, and MDE (U.S. Air Force, U.S. Environmental Protection Agency-Region III, and Maryland Department of the Environment), 2007. Final Record of Decision ST-14, Former East Side Gas Station, Andrews Air Force Base, Maryland, September.

USAF (U.S. Air Force), 2008. Andrews Air 'Force Base General Plan Update, Land Use Control Implementation Plan, ST-14, Andrews Air Force Base, Maryland, April.

USEPA (U.S. Environmental Protection Agency), 2003. Human Health Toxicity Values ill Superfund Risk Assessments, OSWER No. 9285.7-53, December.

USGS (U.S. Geological Survey), 1990. Installation Restoration Program Remedial InvestigationlFeasibility Study, Stage I Report, Andrews Air Force Base, Maryland, prepared for U.S. Air Force, Brooks Air Force Base, Texas.

University of Waterloo, 1996. Groundwater Sampling Results From ST-14, Letter Report from Michaye McMasters, University of Waterloo, Canada, to Mr. C. Jarboe, Andrews Air Force Base, Maryland. • 99 P:\ProjectsIAndrews AFB EnvironmentallFive-year reviewsl4.0 _ DeliverablesI4.I_ReportsIFinallAndrewsAFB_5- Yr Review_Revised March 2011.doc (Thispage intentionally left blank) j j j j j • j j j j j j j j j j j j j j j j j j j j j j j j j j j j j • j j j j j j '-." j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j J Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

5.0 SD-23 FIVE-YEAR STATUS REVIEW

The ROD for SD~23, Sludge Disposal Area 23, was signed on May 31, 2007. The SD-23 ROD is a • No Action ROD documenting that nO,CERCLA action was necessary to protect the public health and the environment from actual or threatened releases of pollutants or contaminants from the site. Hazardous substances, pollutants, or contaminants do not remain at the site above levels that allow for unlimited use and unrestricted exposure; therefore, there is no statutory requirement to perform a five-year review for this site. The following brief review of Site SD-23 status has been included at the request of the USAF and the USEP A.

Information in Subsections 5.1 and 5.2 is based primarily on material presented in the ROD (USAF, USEPA, and MDE, 2007).

5.1 SD-23 DESCRIPTION AND CHRONOLOGY

Site SD-23 is a former sludge disposal area estimated to encompass approximately 834 acres of land that include the two main runways at Joint Base Andie~s. The site extends from Perimeter Road on the north to the headwaters of Piscataway Creek on the south (Figure 5.1). There are several structures present at the site, including various Instrument Landing System transmitter and • receiver antennae and a building thathouses radar and communications equipment. Aside ·from the active taxiways and runways, Site SD-23 is mostly covered with grass that is mowed regularly to keep it short to support flight line and security requirements.

During the late 1950s through the early 1970s when the runway was reconfigured, sewage sludge from the nearby Washington, D.C., Blue Plains Wastewater Treatment Plant (WWTP) was land farmed in various areas between the runways to support vegetation growth (ES, 1985; USEPA, 1998a; MDE, 1988). The sludge was mixed with earthen material to provide up to 24 inches of material to supported vegetative growth. The application of sludge was eventually discontinued because of odor and bird nuisances. The placement of sludge complied with environmental regulations at that time and the sludge disposition areas were not considered to hold'a potential for environmental contamination (ES, 1985). Analysis of sludge from the Blue Plains WWTP. during the 1982 to 1984 timeframe showed concentrations of certain metals such as zinc, lead, chromium, copper, and cadmium slightly above levels that would be found in typical soils in the region (ES, 1985). No records of analytical data for the sludge disposed at SD-23 during the late 1950s through the 1970s were found in a search of likely relevant historical records. • 100 P:\ProjectslAndrews AFB EnvironmentallFive-year reviewsI4.0_ DeliverablesI4.1_ReportslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, fnc. Project Nun/ber 3350092494 (Revised March 2011)

SD-23 is an ERP site that is in the CERCLA process at Joint Base Andrews. A chronology of remedial studies, investigations, and reports at SD-23 is presented below. • • 1985:' Phase I IRP Records Search (ES, 1985) • 1988: Phase II RCRA Facility Assessment (MDE, 1988) • 1995 to 1996: Preliminary Assessment I Site Investigation (Tetra Tech, 1996) • 2001: Preliminary Assessment (URS, 2001) • 2003 to 2007: Remedial Investigation (URS, 2007) • 2007: Record of Decision (USAF, 2007)

5.2 SD-23 BACKGROUND

5.2.1 Physical Characteristics

Site SD-23 encompasses approximately 834 acres in the central portion of Joint Base Andrews, including the two main runways. The site extends from Perimeter Road on the north to the headwaters of Piscataway Creek on the south. Site SD-23 is mostly covered with grass that is mowed regularly to keep it short to support flight line and security requirements.

The surface and subsurface is characterized predominantly by imported fill material, which is c . • predominantly brown, fme sand and silt with minor amounts of gravel and clay that extend to depths ranging between zero and 11 feetbgs.Fill material was brought in to raise the ground surface elevation when the runway was reconfigured. The native soil beneath the fill material is fme~ to coarse-grained sand and quartz gravel with traces of silt and clay.

Groundwater is encountered at depths of 5 to 12 feet bgs at the site. In the southern two-thirds of the site, groundwater flows in a southerly direction toward Piscataway Creek. In the northern portion of the site, groundwater flows east, north, northwest, and west because of mUltiple groundwater divides. The average groundwater flow was estimated at 15 feet per year (URS, 2007).

5.2.2 Land and Resource Use

The SD-23 site is located between and adjacent to the main runways, within the airfield/flight line security zone. There are no plans to change land use (PBS&J, 2009). Land use off-Base, adjacent

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to Joint Base Andrews, includes light industrial, commercial, and undeveloped parcels. No • endangered or rare plants have been identified at SD-23. There are no potable water supply wells located at Joint Base Andrews, including SD-23. There is no current use or exposure to groundwater. Groundwater at SD-23 is not expected to be used for such purposes in the future. Joint Base Andrews is currently served by public water supplied by WSSC, and, according toCOMAR 26.03.01.0S, wells cannot be installed in areas where public water infrastructure is available.

No areas of archaeological or historical significance have been identified at SD-23.

5.2.3 History of Contamination

5.2.3;1 Groundwater

Historically, total metals, SVOCs, and VOCs were detected above tap: water RBCs in several monitoring wells and temporary well point groundwater samples from SD-23. Metals detected in groundwater samples above their respective drinking water MCLs and/or RBCsine1uded aluminum, arsenic, iron, lead, manganese, and vanadium. Aluminum exceeded its secondary MCL • in 32 of 41 groundwater samples. Arsenic exceeded its tap water RBC in 29 of41 groundwater samples and its primary MCL in two groundwater samples (teniporary well point DP01-SD23 and well BWMW-40). Iron exceeded its secondary MCL in 33 of 41 groundwater samples and its tap water RBC in 12 of 41 groundwater samples. Manganese exceeded its secondary MCL in 21 of 41 groundwater samples and its tap water RBC in 6 of 41 groundwater samples. Lead and vanadium were detected in the single groundwater sample from temporary well pointDP01-SD23. In DP01- SD23, lead was detected above its secondary MCL and vanadium was detected above its tap water RBC. Arsenic was the only metal that exceeded its primary drinking water MCL of 10 Ilg/L, and an exceedence occurred only in one well (BWMW -40 at 43.S IlglL) out of the,! 7 wells sampled (a frequency of S.9percent).

Bis(2-ethylhexyl)phthalate was the only SVOC that exceeded both its primary MCL and RBC in samples collected from wells BWMW-02, BWMW-14, BWMW-39, and BWMW-40. Bis(2­ ethylhexyl)phthalate detected in the groundwater sample from well BWMW -40 was qualified as not substantially above the level reported in laboratory or field blanks. Chloroform and TCE were the only VOCs that exceeded their respective RBCs. At well BWMW-lS, TCE was detected at • 102 P:IProjectslAndrews AFB EnvironmentallFive-year reviewsl4.0 _ DeliverablesI4.1_ ReportslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

1.07 IlglL, and exceeded its RBC. At well BWMW -28, chloroform and TCE were detected at 2.86 and 0.43 IlglL, respectively; these concentrations exceeded their respective RBCs. Based on these results, the RI concluded the source of the trace VOC concentrations cannot be inferred. •

5.2.3.2 Geochemical Analysis for Groundwater at SD-23 I

Metals, such as arsenic, are sensitive to changes in groundwater geochemistry caused by r biodegradation of soluble organic material in the groundwater. As discussed previously, sludge . containing organic material from a nearby WWTP was mixed with earthen fill material and applied . to the top 24 inches of the site to help fertilize the soil to establish vegetative growth (ES, 1985). This organic material leached to the groundwater and biodegraded. The biodegradation of the organic material initiated a geochemical reaction in groundwater that caused iron, manganese, and arsenic to dissolve from the native formation at SD-23. The analysis indicated that slightly elevated concentrations of iron, arsenic, and manganese at many of the wells at SD-23 are naturally occurring and are not a direct or indirect result of a release to the aquifer. Only one monitoring well sample out of 17 wells sampled (a frequency of 5.9 percent) contained an arsenic concentration measured at 43.5 IlglL that exceeded its applicable MCL of 10 IlglL. Details of the geochemistry analysis are provided in Appendix I, Human Health Risk Assessment Supplement of the RI (URS, 2007). • Review of the data indicates that slightly elevated concentrations of iron, arsenic, and manganese in the groundwater at SD-23 originate from the native saturated formation at SD-23. Because the solubility of iron, arsenic, and metals is increased as a result of naturally-occurring changes in geochemistry, sample results for iron, arsenic, and manganese from locations impacted by change in geochemical conditions were excluded from the lllIRA. Thus, the exceedence of the MCL of 10 Ilg/L for arsenic in monitoring well BWMW-40 at 43.5 IlglL was excluded. The VOCs and SVOCs data were not eliminated for purposes of the HHRA because the geochemical changes in groundwater did not affect the VOCs or SVOCs.

5.2.3.3 Surface Water

Much of the surface water runoff from SD-23 drains to the south into Piscataway Creek. Analysis of sampling data indicate that runoff from SD-23 has not adversely impacted Piscataway Creek. Three surface water samples (2 primaries and 1 duplicate) were collected at the southern part of SD-23 during the RI. All surface water' samples were analyzed for TCL SVOCs, total and 103

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dissolved TAL metals, cyanide, hardness, and selected field parameters. Total and dissolved metals were detected above drinking water MCLs and tap water RBCs in surface water samples from SD-23. SVOCs were not detected above drinking water MCLs or tap water RBCs in surface • ; water samples.

Total and dissolved metals detected in surface water samples above their respective drinking water MCLs and tap water RBCs included ahmllnum, arsenic, iron, and manganese. Total aluminum exceeded its secondary MCL in all three surface water samples and dissolved aluminum exceeded its secondary MCL in one sample (SW-CHOl). Total and dissolved arsenic exceeded its tap water RBC in all three surface water samples. However, the arsenic levels were 3 to 5 times lower than its MCL of 10 Ilg/L. Total and dissolved arsenic detected in the surface water samples were assigned B flags indicating that the concentrations were neit substantially above the level reported in laboratory or field blanks. Total and dissolved iron exceeded its secondary MCL in all three surface water samples. Total and dissolved manganese exceeded its secondary MCL in one sample (SW-CHOl).

5.2.3.4 Sediment

., Metals, SVOCs, and cyanide in sediment samples were detected above some RBCs and Biological Technical Assistance Group (BTAG) comparison levels from SD-23. However, analysis of sampling data indicate that runoff from SD-23 has not adversely impacted Piscataway Creek. Three (3) sediment samples (2 primaries and 1 duplicate) were collected at the southern portion of

SD-23 durin~ the RI. All sediment samples were analyzed for TCL SVOCs, pesticides, PCBs, TAL metals, cyanide, TOC, percent solids, pH, and grain size. These data were compared to the data collected during the BasewideEcological Risk Assessment (ERA) sampling in the Piscataway Creek.

Metals detected in sediment samples above their respective BTAG screening values included aluminum, antimony, beryllium, total chromium, copper, iron, lead, manganese, mercury, nickel, silver, thallium, vanadium, and zinc. Arsenic was the only metal detected above its industrial and residential RBC values. Cyanide was detected in sediment samples above its BTAG screening value in all three sediment samples. Pesticides in sediment samples were not detected above their respective BTAG screening values and industriaVresidential RBCs, and PCBs were not detected

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Metals detected in all 33 subsurface soil samples above their respective BTAG screening values include aluminum, antimony, beryllium, total chromium, iron, lead, mercury, nickel, silver, thallium, vanadium, and zinc. Arsenic was detected above its industrial and/or residential RBC values in 30 subsurface soil samples. Iron was detected above its residential RBC value in seven surface soil samples, and vanadium was detected above its residential RBC value in one surface soil sample (SB-DP08-0IC from 7 to 9 feet bgs).

SVOCs detected in 2 of 33 subsurface soil samples above their respective BTAG screening values include anthracene, . benzo( a )anthracene, benzo( a )pyrene, benzo(b )fluoranthene, benzo(g,h,i)perylene, benzo(k)fluoranthene, chrysene, fluoranthene, fluorene; indeno(l,2,3­ c,d)pyrene, phenanthrene, and pyrene. Of these SVOCs, benzo(a)pyrene was also detected above residential soilRBCs in subsurface soil sample SB-DPOl-OlB (collected 3 to 5 feet bgs) and its duplicate sample.

Cyanide was detected above its BTAG screening value in all but six subsurface soil samples, and • PCBs were not detected above method detection limits in subsurface soil atSD-23.

In surface soil samples, metals, SVOCs, pesticides, PCBs, and cyanide were detected above various comparison levels.

Metals detected in all 22 surface soil samples above their respective BT AG screenmg values include aluminum, antimony, barium, beryllium, total chromium, copper, iron, lead, mercury, nickel, silver, thallium, vanadium, and zinc. Arsenic was detected above its industrial and/or residential RBC values in all but one surface soil sample. Iron and vanadium were detected above their respective residential RBC values in surface soil samples SS-DP04 andSS-DP17.

SVOCs detected in all 22 surface soil samples above their respective BT AG screening values include acenaphthene, anthracene, benzo(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(g,h,i)pery lene, benzo(k )fluoranthene, chrysene, dibenz( a,h )anthracene, fluoranthene,

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fluorene, indeno(1,2,3-c,d)pyrene, phenanthrene, and pyrene. Of these SVOCs, benzo(a)pyrene, benzo(b)fluoranthene, and dibenz(a,h)anthracene were also detected above industrial and/or • resIdential soil RBCs in surface soil samples SS-DP02, SS~DP03, SS-DP16, SS-DP19, andSS­ DP20(in both primary and duplicate sample).

The pesticide dieldrin was also detected above residential soil RBCs in surface soil samples SS­ DP02, SS-DP03, SS-DP04, SS-DP06, and SS-DP16. The PCB Arochlor-1260 was detected in surface soil samples SS-DP15, SS-DP17, and SS-DP19 above its BTAG screening value. Cyanide was detected above its BTAG screening value in all but two surface SOlI samples..

5.2.4 Initial Response

No response actions have been taken at SD-23.

5.2.5 Basis for No Action

Based on the outcomes of the HHRA and the ERA, the ROD concluded that no remedial action was necessary to protect public health or welfare from actual or threatened releases of pollutants or

contaminants at SD-23. The HHRA concluded that Site SD~23 poses no unacceptable risk to • current and future receptors (including hypothetical future residents) when considering both the RMEand CTE estimates of potential future human health risk. Because of the lack of habitat and risk to potential receptors, the ERA concluded that no action is necessary to protect the environment.

5.3 SD-23 THE SELECTED REMEDY

The ROD for SD-23 was signed in May 2007 documenting the selected remedy for the Site (USAF, USEPA, and MDE, 2007). The selected remedy at SD-23 was No Action.

5.4 SD-23 PROGRESS SINCE LAST FIVE-YEAR REVIEW

This is the fIrst fIve-year review for SD-23.

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5.5 SD-23 FIVE-YEAR REVIEW PROCESS 5.5.1 Community Involvement • The USAF has maintained a public involvement and information program for the ERP since 1990 and niaintains an Administrative Record as required by CERCLA. The Administrative Record is maintained at the Environmental Flight, 3466 North Carolina Avenue; Joint Base Andrews. For the convenience of the public, a copy of the Administrative Record is maintained in an Information Repository located at:·

Prince George's County Memorial Library-Surratts-Clinton Branch 9400 Piscataway Road Clinton, MD 20735

Community involvement activities for this five-year review consisted of publishing a notice in two local newspapers announcing the USAF's intent to perform the five-year review and providing information where and how the public could obtain additional information. The notice appeared in the Prince George's County Gazette on December 3, 2009, and in the Capital Flyer on December 18,2009. A copy of the notice is provided in Appendix A.

5.5.2 DocumentReview • The five-year review included review of the following documents:

-Final Remedial Investigation, Site SD-23 - Sludge Disposal Area (URS, 2007) - Record of Decision, SD-23, Sludge Disposal Area 23 (USAF, USEPA, and MDE, 2007) - General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland (PBS&J, 2009)

5.5.3 Applicable or Relevantand Appropriate Requirement Review

Because no action was necessary at SD-23, no ARARs were identified in the ROD.

5.5.4 Data Review

The remedy for this site does not include data collection. No data were reviewed.

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5.5.5 Site Inspection

The SD-23 site was viewed from outside the airfield/flight line security fence on October 21,2009. • The inspection confIrmed site land use assumptions.

5.5.6 Interviews

No interviews were conducted with community members in regard to SD-23. A public notice was published in two area newspapers in December 2009, indicating that the review process was underway and providing coritact information for questions or comments. No inquiries from the general public were received. Input on the review process was obtained from representatives of the USEPA, MDE, and Prince George's County through their participation in the Tier 1 partnering team and by their review of preliminary drafts of this document.

5.6 SD-23 TECHNICAL ASSESSMENT

5.6.1 Question A: Is the remedy functioning as intended by the decision documents?

Implementation ofInstitutional Controls and Other Measures. The ROD for SD-23 does not require the implementation of LUCs at the site. It should be noted, however, that the BGP • identifies SD:-23 as an active ERP site. This means that Waiver to Construct requirements pertain. In addition, groundwater is prohibited ·from being used for potable purposes anywhere on Base (PBS&J, 2009), and COMAR 26.03.01.05 prohibits installation ofnew water supply wells.

Remedial Action Performance. No remedial actions were required at SD-23.

System Operations/Operation and Maintenance. No remedial systems requiring operation and maintenance have been installed at SD-23.

Cost of System Operations/Operation and Maintenance. There are no remedial operations and maintenance costs at SD-23.

/ Expected Progress Towards Meeting RAOs. No action was required to meet RAOs at SD-23.

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5.6.2 Question B: Are the exposure assumptions, toxicity data, cleanup levels, and remedial action objectives used at the time of the remedy still valid?

Exposure assumptions and toxicity data used in the risk assessment were not reviewed as part of • this status review.

5.6.3 Question C: Has any other information come to light that could call into question the protectiveness of the remedy?

No other information has come to light that calls into question the protectiveness of the remedy.

5.6.4 Technical Assessment Summary

The remedy is performing as anticipated.

/

5.7 SD-23 ISSUES

No issues were ·identified.

5.8 SD-23 RECOMMENDATIONS AND FOLLOW-UP ACTIONS

There are no recommendations for follow-up action. •

5.9 SD-23 PROTECTIVENESS STATEMENT

The selected remedy at Site SD-23 was "No Action". The Human Health Risk Assessment (HHRA) atSD-23 during the RI did not identify any unacceptable risks to human health for unrestricted use. Due to the lack of habitat and risk to potential receptors,' the ecological risk assessment (ERA) concluded that no action is necessary to protect the environment. The no action remedy for SD-23 is protective of human health and the environment under current and potential future land use and associated exposure scenarios.

5.10 SD-23 NEXT REVIEW

SD-23 does not require ongoing five-year reviews.

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5.11 SD-23 REFERENCES

ES (Engineering-Science), 1985, Inc. Installation Restoration Program, Phase I - Records Search, • Andrews AFB, Maryland. MDE (Maryland Department of the Environment, Hazardous and Solid Waste Management Administration), 1988. Phase II RCRA Facility Assessment, Andrews Air Force Base, Camp Springs, Maryland.

PBS&J, 2009. General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland, December.

Tetra Tech, Inc., 1996. Final Installation Restoration Program Preliminary Assessment and Site Investigation Report, AOCs 23-25, 27-29, and IRP Sites FT-02, SS-12, SS-22, and WP-16, Andrews Air Force Base, Camp Springs, Maryland. .

URS, 2001. Andrews Air Force Base, Area of Concern (AOC) 29, Preliminary Assessment.

URS,2007. Final Remedial Investigation, Site SD-23 -.Sludge Disposal Area, Andrews Air Force Base, Maryland.

USAF, USEPA, and MDE(U.S. Air Force, U.S. Environmental Protection Agency-Region III, and Maryland Department of the Environment), 2007. Record of Decision, SD-23, Sludge Disposal Area 23, Andrews Air Force Base, Maryland, May.

USEPA(U.S. Environmental Protection Agency), 1988. Andrews Air Force Base Hazard Ranking • System Documentation Record. USEPA (U.S. Environmental Protection Agency), 2001. "Comprehensive Five-Year Review Guidance"; EPA 540R-01-007, June. .

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• Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 201 I)

6.0 FT-02 FIVE-YEAR STATUS REVIEW

The ROD for FT-02 was signed on October 16, 2009. Remedial actions were still in the design • phase at the time'that this five-year review was prepared. Therefore, this review is a status review that does not fully address all the review elements in USEPA's Comprehensive Five-Year Review Guidance (USEPA, 2001). Because hazardous substances, pollutants, or contaminants currently remain at the site above levels that allow for unlimited use and unrestricted exposure, this is a statutory review under CERCLA.

Information in Subsections 6.1, 6.2, and 6.3 is based primarily on material presented in the ROD (USAF, USEPA, and MDE, 2009).

6.1 FT-02 DESCRIPTION AND CHRONOLOGY

The FT -02 Site, Fire Training Area 1, occupies approximately 97 acres on the west side of the airfield near the center of the Base and was used from the early 1950s to 1958 as.a fire training area . . (Figure 6.1). Located' within a highly active portion. of the Base that is dominated by operation of the runways and taxiways, the site now consists of a concrete taxiway and a grassy area between the taxiway and the runway. The nearest buildings to the site are aircraft hangars, the airfield • control tower,.and various buildings supporting flightline activities.

During the time that it was used for fire training, the site consisted of a bermed area that was 150 to 200 feet in diameter and an adjacent drum storage area. During fire training activities, the bermed area was first saturated with water. Then, approximately 1,000 gallons of flammable liquids consisting of waste fuels, oils, and solvents were poured into the bermed area arid ignited. Protein foams, carbon tetrachloride, and chlorobromomethane were used to extinguish the fires. Fire Araining activities were reported to have occurred two or three times per day (Tetra Tech, 1996). The adjacent drum storage area was reportedly situated on exposed soil and the drums contained hazardous materials such as waste oils, waste fuels, and waste solvents used in the training exercises (Earth Tech, 2008).

Because the Joint Base Andrews airfield has undergone extensive reconfiguration since FT-02 was in operation, the exact location of FT-02 was initially unknown. Review of historical Joint Base Andrews aerial photographs during the Phase I RI produced several potential locations for FT -02, and the Phase I RI focused on the two most probable locations. These areas were identified as FT-' • 111 P:IProjectslAndrews AFB EnvironmentallFive-year reviewsl4.0 _ DeliverablesI4.1_ ReponslFinallAndrewsAFB_5- Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

02 Area 1, located almost directly east of the control tower, and FT-02 Area 2, located at the intersection of what is now the west runway and the taxiway connecting the west and east runways. A historical map discovered subsequent to the completion offield activities 'indicated that what was • believed to be FT-02 Area 1 was not the FT-02 fire training site, but was an aircraft navigational

aid. Despite the lack of photographic evidence oftheexact location ofFT~02, a chlorinated solvent plume was identified and delineated. The plume geometry indicates that the likely source is located to the northwest of the former navigational aid and likely is the result of the former fire training activities at FT-02. The Phase I RI concluded that the most likely location of FT-02 is just . I. . northwest ofFT-02 Area 1, under the Aircraft Parking Apron (Earth Tech, 2008).

FT-02 is an ERP site that is in the CERCLA process at Joint Base Andrews. A chronology of remedial studies, investigations, and reports at FT-02 is presented below.

• 1985: Phase I Installation Restoration Program (JRP) Records Search (ES, 1985) • 1989: Field Investigation (USGS, 1990) • 1996: Preliminary Assessment I Site Inspection (Tetra Tech, 1996) • 2002: Aerial Photograph and Document Review (URS, 2002) • 2003 to 2004: Phase II Site Investigation for AOC-26 (ENSR, 2004) .• 2004: Basewide Background Study (CH2M Hill, 2004) • • 2004 to 2008: Phase I Remedial Investigation (Earth Tech, 2008) • 2008: Phase II Remedial Investigation (URS, 2008a) • 2008: Feasibility Study (URS, 2008b)

6.2 FT-02 BACKGROUND

6.2.1 Physical Characteristics

The FT-02 site consists of a concrete taxiway and a grassy area between the taxiway and the runway. The site area is flat, but it includes limited surface water features such as a drainage swale in the grassy area. Surface water flows from the taxiway towards the adjacent grassy areas. Surface runoff water enters drainage ditches and eventually flows into Piscataway Creek, which is located approximately 3,500 feet south-southeast ofFT-02 (Earth Tech, 2008).

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The shallowest portion of the subsurface consists of fill material that includes construction debris, rubble, and other material. Depth of fill ranges from several feet to over 10 feet (Earth Tech, • 2008). Beneath the fill, the subsurface is composed of Uplands Deposits: fairly clean sands and gravels interbedded with silty sands or sands with clayey sand or silty sand lenses. This fmer material abruptly grades to a dark gray diatomaceous clay (the Calvert Formation). According to Phase I RI data, the top of the Calvert Formation was intersected in all the monitoring well locations at depths ranging from 20 to 33 feet bgs, and elevations ranging from 226 to 240 feet I above msl.

Groundwater in the unconfmed shallow water table is derived primarily from precipitation. Well gauging during the Phase I RI showed groundwater to be at depths ranging from 3 to 15 feet bgs - (248 to 259 feet above msl). Groundwater flow in the northern portion of FT -02 (north of monitoring well MW03-FT02) is towards the south-southeast. However, the Phase I RI data indicated that groundwater flow in the southern portion ofFT-02 (south of monitoring well MW03- FT02) is to the east or northeast.

Groundwater from FT -02 is expected eventually to discharge to Piscataway Creek, which is approximately 3,500 feet south-southeast of FT -02. The estimated average groundwater velocity in • both plumes at FT -02 is moderately slow: approximately 75 feet per year to the southeast in the northern plume and approximately 42 feet per year to the east-northeast in the southern plume (URS, 2008b).

6.2.2 Land and Resource Use

The FT-02 site is located within the active airfield portion of the Base that is dominated by operation of the runways and taxiways. The site consists of a concrete taxiway and a grassy, area between the taxiway arid the runway. The nearest buildings to the site are aircraft hangars, the airfield control tower, and various buildings supporting flight line activities. No residential buildings are present. Land use at· this site is expected to remain dedicated to airfield use for the foreseeable future (PBS&J, 2009).

There are no potable water supply wells located at Joint Base Andrews, including FT -02, and there is no current use or exposure to groundwater. Groundwater at FT-02 is not expected to be used for • such purposes in the future. Joint Base Andrews is currenqy served by public water supplied by

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the WSSC, and, according to COMAR 26.03.01.05, wells cannot be installed in areas where public water infrastructure is available. • There are no archaeological or historically significant cultural resources of importance at FT-02.

6.2.3 . History of Contamination

6.2.3.1 Soil

During the Phase I RI, surface soil and/or subsurface soil samples were collected at various depths in 22 locations. The samples were analyzed for VOCs, SVOCs, and metals, including mercury. Of these samples, only one sample (location DP09, from zero to two feet bgs) contained any contaminant (benzo( a )pyrene) at a concentration exceeding both background levels and USEP A

Region III· industrial risk~based concentrations. The concentration of benzo(a)pyrene in this sample (0.66 mg/kg) was attributed to airfield activities rather than historical activities at FT-02,

since DP09 is located at the edge of the taxiway (Earth Tech, 2008)~ There was no source of groundwater contamination found in soil during the Phase I RI.

I Based on these analytical results, the Phase II RI did not evaluate potential risk from contaminants in soil, and theFS concluded that no remedial action was necessary for soil at FT-02 (DRS, 2008b) •

6.2.3.2 Groundwater

During the Phase I RI, groundwater samples were collected from 45 direct push sampling locations and six monitoring wells. These samples were collected from June 2004 to September 2006.' All of these samples were analyzed for VOCs, and a subset of these samples were also analyzed for' SVOCs, cyanide, metals (including mercury), PCBs, and dioxins. Five VOCs (PCE, TCE, cis-l,2- DCE, vinyl chloride, and carbon tetrachloride) and one metal (arsenic) were detected above USEP A MCLs and background UTLs, if available, in these samples. The maximum detected value of arsenic at DP61-FT02 was below the mean and median values for arsenic in Base-wide background sample concentrations (CH2M Hill, 2004). Because arsenic would not have been a constituent of the waste oil, fuels, solvents, or the extinguishing chemicals used in the historical fire training activities at FT -02, the detected concentrations of arsenic are likely naturally occurring. Both PCE and TCE are believed to have been released at the site as a result of the inclusion of used solvents in the mix of combustible materials used in the fire training exercises. •

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Carbon tetrachloride may have been used as a'fIre extinguishing material. Vinyl chloride and cis- 1,2-DCE are likely breakdown products that are present because of the biologically-mediated • reductive dechlorination of the TCE. The maximum detected concentrations of these fIve VOCs in groundwater at FT-02 are listed below.

Maximum Detected MCL Groundwater Contaminant Concentration (/-lgIL)l Location (/-lglL) PCE 23.4 GPOI-AOC26 5 TCE 1,210 DP59-FT02 5 cis-I,2-DCE 813 DP42-FT02 70 Vinyl chloride 9.0 DP51-FT02 2 Carbon tetrachloride 13.8 MWOI-FT02 5 I Data from 2004 - 2006 sampling for FT-02 Phase I RI (Earth Tech, 2008) or 2003 sampling for AOC-26 Phase II SI (ENSR, 2004). Includes both monitoring well and direct push samples.

Groundwater contamination in the shallow aquifer at FT-02 forms two separate plumes, which are referred to as the "north plume" and the "south plume" .. Based on the lack of contamination within the Calvert Formation at other sites at Joint 'BaseAndrews, monitoring wells and direct push samples were not extended below the Calvert Formation at site FT-02. The most widespread • contaminant in groundwater at the site is TCE. Figure 6.1 depicts, the extent of the two TCE plumes, based on the extent of TCE concentrations exceeding the MCL (5.0 Ilg/L) in monitoring well and direct push samples. The plumes extend underneath the concrete taxiway and the grassy area to the east of the taxiway. The contaminants PCE, cis-I,2-DCE, vinyl chloride, and carbon tetrachloride are present in concentrations exceeding their respective MCLs in limited areas within the boundaries of the two TCE plumes.

6.2.4 Initial Response

No previous response actions were identifIed.

6.2;5 Basis for Taking Action

Based on the analytical data presented in the Phase I RI, soil at FT-02 does not pose unacceptable health effects to potential future receptors. The site also does not pose an unacceptable ecological risk. Therefore, the ROD concluded that no further action is required for soil at FT-02.

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The risk assessment determined that, if groundwater at FT -02 were to be used as a potable source of drinking water, based on its beneficial u,se designation; PCE, TCE, vinyl chloride, carbon tetrachloride, and chloroform are present at concentrations in groundwater at· FT -02 that could • result in unacceptable risks. PCE, TCE, vinyl chloride, carbon tetrachloride were present in site monitoring wells in concentrations above their respective MCLs, and the concentration of chloroform exceeded its USEPA Region III tap water RBC; no federal MCL has been established

) for chloroform. The FS concluded that PCE, TCE, vinyl chloride, carbon tetrachloride, and chloroform represented potential risks that require remediation to restore beneficial uses of the aquifer.

The ROD concluded that response action was necessary to protect public health or welfare from actual or threatened releases of pollutants or contaminants from FT-02 in groundwater ..

6.3 FT-02 REMEDIAL ACTIONS

The ROD for FT-02 was signed on October 16,2009, documenting the selected remedy for cleanup of groundwater associated with known releases at the Site (USAF, USEPA, and MDE, 2009).

) 6.3.1 Remedial Action Objectives • Based on an evaluation of site conditions, an understanding of the contaminants, the results of the risk assessments,andan analysis of ARARs, the ROD identified the following RAOs forFT~02:

• Protect potential future human receptors from exposure to contaminated groundwater and to vapor emanating from the contaminated groundwater above unacceptable risk levels, • Reduce contaminant concentrations to cleanup criteria, and • Restrict the use of groundwater until the cleanup criteria are met.

COCs and cleanup concentrations are listed in the following table.

Contaminants of Concern and Cleanup Criteria at FT-02 Cleanup Criterion Contaminant of Concern (J.I,glL) Basis Tetrachloroethene 5 Trichloroethene 5 cis-l ,2-Dichloroethene 70 116 • P:\Projects\Andrews AFB Environmental\Five-year reviewsl4.0 _ DeliverablesI4.1_ ReportslFinal\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

Contaminants of Concern and Cleanup Criteria at FT -02 Cleanup Criterion Contaminant of Concern (J.121L) Basis

Vinyl Chloride 2 MCL I • I Carbon Tetrachloride 5 MCL Chloroform 15 Risk·based2 Dichloromethane 5 MCL I I Cleanup criterion is the drinking water MCL (USAF, USEPA, and MDE, 2008). 2 Risk-based cleanup criterion for chloroform derived in Phase II RI (URS, 2008a).

6.3.2 The Selected Remedy

The selected remedy at FT-02 was FS Alternative 4: Enhanced Bioremediation through Carbon Substrate Injection and Bioaugmentation. The remedy addresses groundwater contamination and potential future exposure to contaminated groundwater. . The major components of the selected remedy consist of the following:

• Inject a carbon substrate and microbes that can biologically treat the groundwater contaminants at FT-02.

• Perform groundwater monitoring to determine the effectiveness of the injections ill .' treating the groundwater contaminants. • • Implement and maintain ICs in the form ofland and groundwater use restrictions until the cleanup criteria are achieved. • Conduct five-year reviews to evaluate the effectiveness of the remedy until cleanup criteria are achieved.

6.3.2.1 Injection ofa Carbon Substrate and Microbes

The selected remedy involves injection of a mixture of a carbon substrate and naturally-occurring microbes known to degrade chlorinated solvents in the saturated zone at FT-02. The addition of the microbes, also known as bioaugmentation, was included in this alternative as a contingency in case the native microorganisms are unable to completely break down the groundwater contaminants. The components of the injection program to be implemented at FT-02 include:

• Injection of a carbon substrate into rows known as Permeable Biostimulation Barriers (PBBs). The groundwater contaminants would be treated as the groundwater flows through the PBBs over time. The representative substrate, for cost estimation purposes, is AquaBupH, which includes a long-release alkaline component to increase pH.

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• Injection of dechlorinating microbes into the PBBs to ensure the complete degradation of • PCE, TCE, and its daughter products to ethene. The BAC-9 product was selected as a representative inoculum.

The ROD allows the choice of substrate or the decision to bioaugment to be adjusted during the design phase of the remedy. In addition, the locations and number of the .initial injection points may be adjusted during the remedial design based on design data, design analysis, locations of utilities, or field observations. The locations and number of injection points, frequency of re­ injection, choice of substrate, and other operational components of the remedy may be adjusted over time as new data are analyzed.

For the cost estimates used in the FS,a remediation timeframe of 15 years was assumed as a reasonable timeframe. This timeframe included 12 years for the groundwater contammants to be conveyed by groundwater flow through the PBBs, at which time the substrate from the last injection event is predicted to expire, followed by three additional years of confirmation sampling. The remedial time frame can be refmed as more data are collected as part of the groundwater monitoring program. 6.3.2.2 Groundwater Monitoring Program • The groundwater monitoring data are to be used to determine the effectiveness of the PBBs in treating the groundwater contaminants and determine the frequency and locations for re-injection. The components of the groundwater monitoring program to be implemented at FT-02 include:

• Installation ofJour additional groundwater' monitoring wells as part of the groundwater monitoring program. • Semi-annual sampling of 10 monitoring wells (six existing and 4 new) for the first three years ofthe remedy, including the baseline sampling event. • Annual sampling of 19 monitoring wells after year three of the remedy.

The number and locations of the new monitoring wells may be adjusted during the design phase of the remedy. The monitoring program can be refmed as riew data are analyzed.

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6.3.2.3 Institutional Controls

ICs are necessary at FT -02 because groundwater contaminants remain at concentrations that exceed • those allowing unlimited use and unrestricted exposure, and exposure to FT -02 groundwater could pose a risk to human health until cleanup criteria are attained. The general areas for which ICs are to be implemented are shown on Figure 6.1. The area for which ICs are to be implemented may be adjusted over time as new data are analyzed.

The objectives of the ICs at FT-02 are the following:

• Ensure there is no potable use of impacted shallow groundwater at the site until cleanup criteria are met and acceptable risk levels are achieved based upon cumulative risk in order to eliminate the exposure of potential receptors to groundwater contaminants; . . • Ensure that excavation, construction, or any similar activities occurring within the area identified in Figure 6.1 do not reduce performan'ie of the remedy, interfere with the ability to undertake required environmental monitoring, or cause the plume to migrate beyond the footprint identified in Figure 6.1; • Ensure that workers performing any excavatiori, construction, or any similar activities are protected from exposure producing an unacceptable risk by implementation of a health and safety plan; • Ensure that land use is consistent with RAOs and does not interfere with the selected • remedy or long-term operations and maintenance activities; • Ensure that the groundwater monitoring wells are protected from damage and thatICs are otherwise effective by undertaking annual inspections; • Ensure that any impacted groundwater that exceeds relevant regulatory criteria is appropriately handled and disposed of during construction, short- and long-term monitoring activities, as well as operation and maintenance activities; and • Ensure that site use is not inconsistent with the current and future land use presumptions relied upon in the FS until such time that the implemented remedy has achieved the cleanup criteria.

The USAF is responsible for implementing ICs atFT-02. As part of the selected remedy, the area illustrated in Figure 6.1 is to be designated as a "restricted use" area in the Base GIS. This designation prohibits activities such as residential development or potable use of groundwater. Additionally, Base-wide groundwater use is currently restricted, as documented in the BGP, and procedures are in place to limit contact with groundwater through the issuance of dig permits and other protective measures. Records of the groundwater contamination will be kept in the Base

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GIS/environmental database. The restricted-use designation will remain in place until groundwater monitoring indicates that the cleanup criteria have been inet at FT-02. • Any activity that is inconsistent with the IC objectives or use restrictions, or any other action that may interfere with the effectiveness of the ICs is to be addressed by the USAF as soon as practicable. In no case will the process be initiated later than 10 days after the USAF becomes aware of the breach. The USAF will notify USEP A and MDE regarding how the USAF has addressed or will address the breach within 10 days of sending USEP A and MDE notification .of the breach. The ICs can be modified as new data are analyzed; however, the USAF will not modify or terminate ICs, implementation actions, or modify land use without approval by USEPA and the MDE. The USAF will seek prior concurrence before any anticipated action that may disrupt the effectiveness of the ICs or any.action that may alter or negate the need for ICs. Joint Base Andrews shall notify USEP A and MDE 45 days in advance of any proposed land use changes that are inconsistent with IC objectives or the selected remedy.

The ICs proposed for FT-02 are the following:

• Review and approval of any changes in land use, including construction of new facilities • or additions to existing facilities at FT-02, by the Joint Base Andrews Facility Review Board, which interacts with the Corrimunity Planner using the BGP as a guide to land use issues. The purpose of the review is to ensure consistency with the prohibition of construction of any facility, building, or any structure that would have a negative impact on the remedy in meeting the RAOs. • Inclusion ofthe restrictions at FT-02 in the BGP. All ERP sites and restrictions at Joint Base Andrews are identified in the BGP. Any proposed activity or construction on an ERP site requires an "ERP Waiver to Construct" memorandum, approved and signed by the USAF. • Review of proposed construction activities at FT-02 by Joint Base Andrews Environmental Flight through the following processes: Environmental Impact Analysis Process (EIP A), NEPA Design Reviews of Proposed Construction, review of routine Work Orders that involve alterations to facilities, and review of Dig Permits. • Posting signs at the site identifying FT-02 as a'CERCLA site. The signs will state that no construction or excavation activities, and no groundwater use·or withdrawal, is permitted within the area without written authorization by the USAF. Contact information for the ERP project manager will also be included on the signs. • Restriction of access. Access to FT -02 is extremely limited because it is located within the airfield that is enclosed by a security fence (within and in addition to the Base perimeter security fence) controlled by Joint Base Andrews security personnel. Access to the site is restricted to personnel with a security clearance and a flight line access badge, • or to someone under their direct escort.

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• Continued prohibition of potable use of groundwater. Potable use of groundwater is prohibited at FT-02 and at Joint Base Andrews in total. COMAR 26.03.01.05.A prohibits issuance of a permit to individual residents or businesses for private water supply wells • when public water supplies are available; therefore, the installation of groundwater wells intended for potable use will not be approved at the site. ReView of Work Orders and Dig Pennits by Joint Base Andrews Environmental staff also will ensure that potable groundwater wells will not be installed at FT-02. • Notification of the USEPA and MDE regarding any activity that impacts IC objectives at FT-02.

The ICs can be modified as new data are analyzed. The ICs are to remain in place until the concentrations of PCE, TCE, cis-1,2-DCE, vinyl chloride,catbon tetrachloride, chloroform, and dichloromethane at the site allow for unlimited use and unrestricted exposure. Evaluation of the effectiveness of the environmental use restrictions and controls will be conducted annually by Joint Base Andrews. The monitoring reports will evaluate the status of the ICs and how any IC deficiencies or inconsistent uses have been addressed. The monitoring results will be included in a separate report or as a section of another environmental report, if appropriate, and provided to USEPA and MDE for informational purposes. The annual monitoring reports will be used in . preparation of the five-year review, which will evaluate if the remedy is protective of human health • and the environment and the effectiveness of ICs.

6.3.3 Remedy Implementation

The remedial action for FT-02 was in the design phase at the time this five-year review report was prepared. It is anticipated that remedial design remedial actions will be completed before the end of2010.

6.3.4 System Operations/Operation and Maintenance

Installation of remedial systems at FT702 that require operation and maintenance is not anticipated.

6.4 FT-02 PROGRESS SINCE LAST FIVE-YEAR REVIEW

This is the first five-year review for FT -02 .

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6.5 FT-02 FIVE-YEAR STATUS REVIEW PROCESS 6.5.1 Community Involvement • The USAF has maintained a public involvement and information program for the ERP since 1990 and maintains. an Administrative Record as required by CERCLA. The Administrative Record is maintained at the Environmental Flight, 3466 North Carolina A venue, Joint Base Andrews. For the convenience of the public, a copy of the Administrative Record is maintained in an Information Repository located at:

Prince George's County Memorial Library-Surratts-Clinton Branch 9400 Piscataway Road Clinton, MD 20735

Community involvement activities for this five-year review consisted of publishing a notice in two local newspapers announcing the USAF's intent to perform the five-year review and providing information where and how the public could obtain additional information. The notice appeared in the Prince George's County Gazette on December 3, 2009, and in the Capital Flyer on December 18, 2009. A copy ,?f the notice is provided in Appendix A.

6.5.2 Docuinent Review •

The five-year review included review of relevant documents including the following:

• Final Basewide Conceptual Site Model (URS, 2006) • Final Phase II Remedial Investigation, FT-02, Fire Training Area 1 (URS,2008a) • Final Feasibility Study, FT-02, Fire Training Area 1 (URS,2008b) • Final Record of Decision FT-02, Former Fire Training Area 1 (USAF, USEPA, and MDE,2009) • General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland (PBS&J,2009)

6.5.3 Applicable or Relevant and Appropriate Requirement Review

, The ARARs presented in Appendix B of the ROD are reprinted and appended in Appendix E of this report. These standards and regulations were considered current at the signing of the ROD and have not been reviewed as part of this review. 122 • P:\Projects\Ancirews AFB EnvironmentalIFive-year reviewsl4.0 _ DeliverablesI4.1_ ReportslFinal\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

6.5.4 Data Review

The groundwater monitoring required under the 2009 ROD had not commenced at the time of this • review; therefore, no data review was performed.

6.5.5 Site Inspection

The FT-02 site was viewed from outside the airfield/flight line security fence on October 21, 2009. The inspection confmned site land use assumptions.

6.5.6 Interviews

No interviews were conducted with community members in regard to FT-02. A public notice was published in two area newspapers in December 2009, indicating that the reVIew process was underway and providing contact information for questions or comments. No inquiries from the

general public were received. Input on the rev~ew process was obtained from representatives of the USEPA, MDE, and Prince George's County through their participation in the Tier 1 partnering , . team and by their review of preliminary drafts of this document.

• 6.6 FT -02 TECHNICAL ASSESSMENT The remedy for FT-02 is in the early stages'ofimplementation; therefore, its performance could not be fully assessed in accordance with USEP A guidance

6.6.1 QuestionA: Is the remedy functioning as intended by the decision documents?

Implementation ofInstitutional Controls and Other Measures. A LUCIP has not been drafted for FT-02;however, the BGP identifies FT-02 as an active ERP site (PBS&J, 2009). Therefore, a Waiver-to-Construct is required for all proposed construction at the site (API 32-1021). A Waiver­ to-Construct means the proposed construction has been evaluated with respect to site activity and environmental risks proposed by the construction and ultimate use of the facility.

In addition, groundwater is prohibited from being used for potable purposes anywhere on Base (PBS&J, 2009), a,nd COMAR 26.03.01.05 prohibits installation of new water supply wells. FT-02 is within the airfield security zone and access is limited to personnel with airfield/flight line security badges. 123

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System Operations/Operation and Maintenance. Remedial actions have not yet been completed at FI-02; therefore, assessment of .system operations/operation and maintenance could not be completed.

Cost of System Operations/Operation and Maintenance. Remedial actions have not yet been completed at FI-02; however, there were estimated costs of $54,000 in 2009 related to groundwater monitoring.

Expected Progress Towards Meeting RAOs. Remedial actions have not yet been implemented at FI-02; therefore, assessment of progress towards meeting RAOs could not be completed.

6.6.2 Question B: Are the exposure assumptions, toxicity data, cleanup levels, and remedial action objectives used at the time of the remedy stiU valid? • Land use at FI-02 has not changed since ROD signature and remains dedicated to airfield use (i.e., aprons and taxiways). No changes in current or reasonably foreseeable future site conditions affecting remedy protectiveness were identified as part of this five-year review.

The toxicity data, cleanup levels, and RAOs for FI-02 were considered current at the signing of the ROD and have not been reviewed as part of this review. The risk .assessment methodology and contaminant characteristic data used in the risk assessment were also considered current and were not reviewed.

6.6.3 Question C: Has any other information come to light that could caU into question the protectiveness of the remedy?

No information has come to light during this review that could call into question the protectiveness of the remedy.

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6.7 FT -02 ISSUES • No issues were identified. 6.8 FT-02 RECOMMENDATIONS AND F«;lLLOW-UP ACTIONS

There are no recommendations for follow-up other than to implement the selected remedy.

6.9FT-02 PROTECTIVENESS STATEMENT

There has been insufficient time since ROD signature to implement the selected remedy at FT -02; therefore, a protectiveness statement cannot be made.

6.10 FT-02 NEXT REVIEW

FT -02 is a statutory site that reqUITes ongomg five-year reVIews. The next reVIew will be performed within five years of the completion of this five-year review report. The completion date is the dateofthe signature shown on the signature cover attached to the front of this report. • 6.11 FT-02 REFERENCES CH2M Hill, 2004. Basewide Background Study Report, Andrews Air Force Base, Maryland, September.

CH2M Hill, 2005. Basewide Ecological Risk Assessment, Step 7, Andrews Air Force Base, Maryland, March.

Earth Tech, 2008. Final Report for the Phase I Remedial Investigation, FT -02, Fire Training Area 1, Andrews Air Force Base, Maryland, January.

ENSR, 2004. Phase II Site Inspections Areas of Concern 24, 25, 26, Andrews AFB, MD, February.

ES (Engineering Science), 1985. Phase I Records Search, Aniliews AFB, Maryland, June.

PBS&J, 2009. General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland, December.

Tetra Tech, Inc., 1996. Final ERP RCRA Facility Investigation/Correction Measures Study Technical Report, Andrews AFB, Maryland, April.

URS,2002. Review of Historical Documents and Aerial Photos, FT-02, Andrews Air Force Base. • 125 P:\ProjectsIAndrews AFB EnvironmentallFive-year reviewsl4.0 _ DeliverablesI4.1_ ReportslFinallAndrewsAFB _5-Yr Review_Revised March 201l.doc Joint Base Andrews - First Five-Year Review· November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 201 I)

URS, 2006. Final Basewide Conceptual Site Model, Andrews Air Force Base, Maryland, December.

URS, 2008a.Final Phase II Remedial Investigation, FT -02, Fire Training Area I, Andrews Air Force Base, Maryland, May.

URS, 2008b. Final Feasibility Study, FT-02, Fire Training Area 1, Andrews Air Force Base, Maryland, August.

USAF, USEPA, and MDE (U.S. Air Force, U.S. Environmental Protection Agency-Region III, and Maryland Department of the Environment), 2009. Final Record of Decision FT-02, Former Firy Training Area 1, Andrews Air Force Base, Maryland, October.

USEPA (U.S. Environmental Protection Agency), 200l. "Comprehensive Five-Year Review . Guidance"; EPA 540R-OI-007, June.

USEPA (U.S. Environmental Protection Agency), 2007. USEPARegion ill RBC Table, October.

USEPA (U.S. Environmental Protection Agency), 2008. Office of Groundwater and Drinking Water. Drinking Water Contaminants, List 'of Contaminants & their MCLs. http://www .epa.gov/safewater/contaminants/index.html (accessed 5/16/2008).

USGS (U.S. Geological Survey), 1990. Andrews Air Force Base Data Summary for Site 6 - FTl Fire Training Area 1, 1990. •

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7.0 FT-03 FIVE-YEAR STATUS REVIEW

The ROD for FT-03, Fire Training Area 2, was signed on October 2, 2008. TIle selected remedy • for Site FT03 has not been fully implemented .as of the writing of this report; therefore, this review is a status review that does not fully address all the review elements in USEPA's Comprehensive Five-Year Review Guidance (USEPA, 2001). Because hazardous substances, pollutants, or '­ contaminants currently remain at the site above levels that allow for unlimited use and unrestricted exposure, this is a statutory review under CERCLA.

Information in Subsections 7.1, 7.2, and 7.3 is based primarily on material presented in the ROD . , (USAF and USEP A, 2008).

7.1FT-03 DESCRIPTION AND CHRONOLOGY

Site FT~03 occupies approximately 16 acres southwest of the west runway at Joint Base Andrews (Figure 7.1). Fire training activities occurred at a 300- to 400-foot diameter training area within the site from 1959 until 1972. During fIre training activities, a bermed area was saturated with water; then, an estimated 1,000 to 2,000 gallons of flaDlffiable liquids consisting of waste oil, jet fuel, paint thinner, and other liquids were poured into the bermed area and ignited. Protein foams, '\ • carbon tetrachloride, and chlorobromomethane were then used to extinguish the fIres. Fire training activities were reported to have occurred two or three times per day until the mid 1960s, when they were reduced to once per day (USGS, 1989). The adjacent drum storage area was reportedly situated on expo sect soil, and the drums contained hazardous flammable materials such as waste oil, jet fuel, paint thinner, and other liquid wastes from shops at Joint Base Andrews. The exact location of the drum storage area, however, is unknown because it was never located on any historic aerial photographs or identifIed duri:il.g any investigation (USAF and USEPA, 2008).

In addition to the fIre training activities, a small, uri.identifIed area of FT-03 immediately adjacent to the fIre training area may have been used for the burial of several hundred fIve-gallon containers of leaded motor vehicle gasoline (MOGAS) in the late 1960s. This information was based on a single source and has not been verifIed by any other personnel familiar with the activities at FT -03.

When FT -03 was demolished Clfca J 972, contaminated soil was removed. There is no documentation of the volume of soil removed or if there were any established cleanup criteria. Clean soil was brought in, the site was graded, sludge was applied to aid in grass growth, and • 127 P:\Projects\Andrews AFB Environmental\Five-year reviewsI4.0_DeliverablesI4.1_ Reports\Final\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, inc. Project Number 3350092494 (Revised March 2011)

soccer fields were constructed. In 1995, a golf course was built in the area. The 14th hole green, . 15th hole tee box, and 17th hole fairway of the South Course now cover the location of the former FT-03 site. The 16th hole is also located within the overall FT -03 site area. During the building of • soccer fields and the golf course, surface soil at FT-03 was graded and subsequently covered with at least two to four feet of clean fill. Consequently, subsurface soil at FT -03 beneath the clean fill is the primary affected medium.

The potential contaminant sources at FT -03 . are the waste oils, jet fuels, paint thinner, fire extinguishing. chemicals, and other liquid wastes that were not consumed during the fire training exercises, as well as spills or releases in the druiD storage area. Any material remaining following

fire training ac~ivities would have been absorbed into the soil column and potentially could have migrated into groundwater beneath the site. Residual chemicals potentially present from the fire training activities include VOCs, including chlorinated solvents and BTEX; SVOCs; TPH; PCBs; and metals. . Sewage sludge reported to have been applied at the site could also be .a potential source of contamination.

FT-03 is an ERP site .that is in the CERCLA process at Joint Base Andrews. A chronology of remedial studies, investigations, and reports at FT-03 is presented below. • • 1959 to 1972: FT-03 used forfrre training • 1972 (approx): FT-03 demolished (USGS,1989) • 1985: Phase I Soil Investigation and Records Search (EA, 1985) • 1989: Field Investigation (USGS, 1989) • 1992: Risk Assessment and Technical Memorandum (Dames & Moore, 1992) •. 1995: Soil investigation (Glenn and Sadler, 1995) .• 1996: Preliminary Assessment and Site Investigation (Tetra Tech, 1996) • 2002: Groundwater sampling (IT, 2002) • 2003: Groundwater sampling (MACTEC, 2003) • 2004: Remedial Investigation (Earth Tech, 2004) • 2008: Focused Feasibility Study Report (Tetra Tech, 2008) • 2008: Record of Decision (USAF and USEPA; 2008) -. 128

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7.2 FT-03 BACKGROUND • 7.2.1 Physical Characteristics FT-03 is dominated by flat grassy areas interspersed with small knolls/mounds: Surface runoff at FT-03 is controlled by the rolling ground surface of the golf course, and the several sand traps present at the site are not thought to. noticeably affect the site hydrology. In order to maintain the golf course grass cover, it is irrigated during dry periods to mimic average rainfall conditions. During periods of heavy rainfall, surface water flows from the course into drainage ditches adjacent to the roads that border the site. Surface water from FT-03 eventually enters Piscataway Creek approximately 3,000 feet east-southeast of FT-03. There are no natural or manmade surface water bodies on FT-03. The closest surface water body to FT-03 is Freedom Lake, located approximately 1,200 feet southeast of the site.

The original ground surface was altered during grading activities and when the fIre training area was decommissioned. Two to four feet of clean fIll was placed on. top. of FT -03 during construction of the South Golf Course. The fIll material used to construct the golf course included soil and other materials capable of enhancing site drainage and ultimately supporting the turf grass covering the course. The RI documented that the thickness of this soil layer varies, but it is • generally greater than 20 inches. Prior to construction of the golf course, FT -03 surface soil was classifIed as smooth Udorthents (UI) in the U;S. Department of Agriculture Natural Resource Conservation Service's Soil Survey of Andrews AFB (USDA, undated).

During theRI at FT-03, soils at the site were found to include a wide-variety of soil types consistent with construction activities at the golf course. Silts, clays, sands, and gravel were all encounteredib. the upper 5 to 10 feet during soil sampling. A layer of charred material identifIed in the subsurface that may represent the surface of the former fIre traming area was encountered in 6 of the 14 boreholes. The depth of this charred material layer (thickness less than one foot) varied from 4 to 15 feet bgs. Samples ofthis material were collected for laboratory analysis, and trace levels of SVOCs and metals including arsenic were detected.

The former ground surface at FT-03 was described as unconsolidated fme to coarse sand with gravel and some silt and clay layers (USGS, 1989). This original ground surface represents the fIrst soil layer that could have been contaminated by the FT -03 activities. This layer consists of undifferentiated Upland Deposits that are found across Joint Base Andrews. The depth to the • 129 P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0_Deliverables\4.I_Reports\Final\AndrewsAFB_5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011) underlying low-permeability aquitard (the Calvert Formation) has not been determined at FT-03. Based on investigations at FT-03 and adjacent areas, the Calvert Formation is likely found between 35 and 50 feet bgs at FT-03. •

Shallow groundwater in the area is found in the Upper Miocene to Pliocene-age Upland Deposits. The shallow unit is unconfmed and consists of unconsolidated deposits (sands, gravels, silts, and clays). At FT-03, the groundwater depth varies from approximately 8 to 21 feet bgs. In the shallow unit, average yield ranged between two and five gallons per minute, while the maximum yield was recorded as high as 12 gallons per minute. Groundwater flow is generally from west to east (see Figure 7.1). Groundwater velocity is estimated to be between 0.2 and 28 feet per year.

7.2.2 Land and Resource Use

The FT -03 site is located southwest of the west runway and is currently located beneath part of the

Joint Base Andrews South Golf Course. The land use at FT ~03 is expected to remain recreational for the foreseeable future.

There are no potable water supply wells located at Joint Base Andrews, including FT-03, and there is no current use or exposure to groundwater. Groundwater at FT -03 is not expected to be used for such purposes in the future. Joint Base Andrews is currently served by public water supplied by • the WSSC, and, according to COMAR 26.03.01.05, wells cannot be installed in areas where public water infrastructure is available.

There are no archaeological or historically significant cultural resources of importance at or in the vicinity ofFT-03.

7.2.3 History of Contamination

This subsection summarizes the nature and extent of contamination in groundwater and soil at FT-03 based on the data collected during the RI. Based on the results of investigations of the site, FT-03 was split into two areas, Areas 1 and 2, for purposes of evaluating potential exposure to soil and groundwater contaminants. Area 1 covers the former fire training pits, and Area 2 is located in the northern part of the site where soil disturbance activity was noted in historical aerial photographs.

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During the RI, fourteen soil borings were advanced at FT -03 at locations based on a review of previous data and historical aerial photos. Soil and groundwater samples were obtained from these • borings, and VOCs were detected that included primarily petroleum products and breakdown compounds. Concentrations of VOCs found in surface and subsurface soil did not exceed USEP A Region III industrial RBC screening values. SVOCs, including benzo[a]pyrene, were detected at concentrations exceeding industrial RBCs. The results showed that the highest concentrations of benzo[a]pyrene. occurred in samples six to eight feet bgs collected from boring location DP09 in the vicinity of where fIre training activities had occurred. Becausedetect~d contamination was six to eight feet deep, it was concluded that there is little potential for human exposure.

In groundwater, five VOCs exceeded Region III tap water RBCs in samples collected from temporary borings (as opposed to groundwater. samples collected from constructed monitoring wells). However, none of these detections exceeded applicable MCLs, suggestirig that VOCs are not a chemical category of concern in groundwater at this site. Monitoring well samples deteCted nine VOCs in groundwater at FT-03; however,no detections exceeded the respective MCLs. One

SY~C, benzo(a)pyrene, exceeded the then current tap water RBC of 0.0092 IlglL in groundwater samples from wells MW04 and MWll at concentrations of 0.047 IlglL and 0.013 IlglL, respectively. These concentrations also exceed the current RBC of 0.0029 IlglL. Arsenic and iron • were detected in groundwater at concentrations exceeding their respective tap water RBCs. Arsenic exceeded its tap water RBC of 0.045 IlglL in three monitoring wells, with detections ranging from 4.9 to 7.7 Ilg/L. None of these detected arsenic concentrations exceeded the .arsenic MCL of 10 11 gIL. Iron exceeded the then current RBC of 11,000 IlglL in three of eight wells at concentrations that also exceeded the Base-wide background concentration (20,100 11 gIL) , with detections ranging from 27,000 to 59,000 IlglL. These concentrations also exceed the current RBC for iron of 26,000 IlglL. The fact that these background exceedances occurred in only three of eight monitoring wells indicates that they may not be representative of overall site .conditions (USAF and USEP A, 2008).

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7.2.4 Initial Response

Nojnterim removal actions have occurred at FT-03; however, during the dismantling of FT-03 in the early 1970s, contaminated soil was removed. There is no documentation concerning the • volume of soil removed, or if there were any established cleanup criteria for soil to protect groundwater resources (USAF and USEP A, 2008).

7.2.5 Basis for Taking Action

Based on the risk assessment, the ROD concluded that there is no risk to current or reasonably anticipated future users of the site (golfers and maintenance workers) through exposure to either soil or groundwater. Contaminants in groundwater were detected at levels below MCLs, which indicates that movement of contaminants froin soil into groundwater has been limited. Natural degradation ofbenzo(a)pyrene in groundwater may occur over time reducing the concentrations.

Although groundwater at FT-03 is not currently being used for potable supply or any other purpose, it is remotely possible that, in the future, the groundwater 'could become a resource for residential use. Also, naphthalene in' soil poses an inhalation risk to hypothetiCal future residents. For these reasons, a remedial action is required to determine when groundwater conditions allow for unlimited use and unrestricted exposure and, in the meantime, to ensure that the groundwater is • not used as a potable supply or for washing purposes. . The remedial action is also required to restrict land use to ensure that naphthalene in soil does not pose an inhalation risk.

The ROD concluded that response action was necessary to protect public health or welfare from actual or threatened releases of pollutants or contaminants from FT-03 in soil and groundwater.

7.3 ·FT-03 REMEDIAL ACTIONS

The ROD for FT-03 was signed on October 2,2008, documenting the selected remedy for cleanup of groundwater associated with known releases at the Site (USAF and USEP A; 2008).

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7.3.1' Remedial Action Objectives

Based on an evaluation of site conditions, an understanding of the contaminants, the results of the • risk assessments, and an analysis of ARARs, the ROD identified the following RAOs for FT-03:

• Protect human receptors from exposure to contaminated subsurface soil; and • Restrict the use of shallow groundwater until it does not pose an unacceptable risk.

Subsection 2.8 of the ROD specifically states that "Unlimited use of, and unrestricted exposure to, the site was considered and rejected as a RAO". However, Subsection 2.9.7 of the ROD describes)

unrestricted use of groundwater as a long~term goal and provides the following approach for groundwater assessment:

"To gauge whether the groundwater is ready for unlimited use and unrestricted exposure, the site conditions would be monitored wider Alternatives 3, 4, and 5 and a human health risk assessment would be conducted to documentacceptable risk levels. If in the future the USAF determines that it would prefer that the land use be available for an alternative use, subsurface soils could be sampled and the results statistically analyzed (using a Mann­ Kendall Test and trend analysis) to determine if an acceptable risk level has been reached."

"If acceptable risk levels in groundwater have been attained, then beneficial use has been restored to the shallow aquifer. If . acceptable risk levels have been attained for • benzo(a)pyrene, but not for arsenic and chromium, theri a statistical comparison to background could determine whether background levels have been achieved for arsenic and chromium. Pursuant to CERCLA Section 104(a)(3)(A), naturally occurring substances are exempt from CERCLA response authority; thus hazardous substances, pollutants or contaminants determined to be background do not require response under CERCLA."

COCslisted in the ROD for FT-03 are presented in the following table.

Contaminants of Concern at FT -03 Contaminant of Concern Cleanup Criterion * MCL* Benzo(a)pyrene Not established in ROD 0.2 Naphthalene Not established in ROD NA Arsenic Not established in ROD 10 Chromium Not established in ROD 100 Note: * Cleanup criteria are not identified in the ROD. MCLs are listed here for information purposes only. NA = A contaminant-specific MCL has not been established for naphthalene. The. ROD was prepared based on the premise that MCLs for the listed COCs were not being exceeded.

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7.3.2 The Selected Remedy

The selected remedy at FT-03 was FFS Alternative3: ICs and Monitoring. The remedy addresses groundwater contamination and potential future exposure to contaminated groundwater. The • remedy was selected in recognition of the following site circumstances:

• There is no current or likely future unacceptable risk because the land use is expected to remain as recreational; and • Future potable use of shallow groundwater at the site is extremely unlikely because drinking water wells are prohibited by State ofMaryland regulation at this location.

Based on Subsection 2.12.2 ofthe ROD, the major components of the selected remedy consist of the following:

• Install groundwater monitoring wells and perform groundwater monitoring to determine concentration trends of COCs (naphthalene, benzo(a)pyrene, chromium, and arsenic) through statistical evaluation (using a Mann-Kendall Test and trend analysis) and to serve as the basis for conducting five~year reviews. The monitoring program will continue to be implemented until a HHRA· demonstrates achievement of acceptable risk levels. If the groundwater monitoring program is altered, changes will be concurred upon by USEPA • before implementation and then documented and subsequently reported in the five-year review report. • Implement and maintain ICs to restrict land use to ensure that residential use does not occur, industrial uses are protective, and construction workers are appropriately protected (until such time .as a change in land use.is approved in accordance with Subsection 7.3.2.2). • Implement and maintain ICs for groundwater until a HHRA demonstrates achievement of acceptable risk levels.

7.3.2.1 Groundwater Monitoring and Statistical Trend ·Evliluations

As described in the ROD, the components of the groundwater monitoring program to be implemented at FT-03 include:

• Installation. of groundwater monitoring wells to conduct the groundwater monitoring program. The number of groundwater monitoring wells and their locations will be determined and concurred upon by USEP A as part of the remedial design/remedial action work plan. • Semi-annual sampling for· the first two years of groundwater monitoring. Ifa COC is not detected after four consecutive sampling events, it will be dropped as a coe. •

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• Annual sampling during years three, four, and five of the first five-year cycle (three sampling events total). • After the first five years following implementation of the remedy, the groundwater • monitoring program will continue at five~year intervals [unless otherwise modified based on evaluation/review of monitoring data as described below] until concentrations of COCs have decreased to allow for unlimited use and unrestricted exposure. .• Statistical analysis of monitoring data (using a Mann-Kendall Test and trend analysis) to assess trends in naphthalene, benzo(a)pyrene, chroniium, and arsenic concentrations. Ifa rebound in the COCs is observed, the monitoring frequency may need to be increased to provide sufficient information for a protectiveness determination in the next five~year reVIew. • Five-year reviews to confirm the concentration or absence of tOCs at the FT-03 site and to deterniine if hillllan health and the environment are continuing to b.e protected by the remedy. The gathered data will also be used to evaluate the long-term monitoring program and to deterniine if the groundwater monitoring program should be increased, decreased, or remain unaltered for another five-year review cycle; or if more active/aggressive remedial action is needed to achieve unlimited use and unrestricted exposure. The data collected for the long-term monitoring program will be analyzed and relied upon to support proposed changes to the monitoring frequency as well as to deterniine if site conditions allow for unlimited use and unrestricted exposure such that ICs can be eliminated.

7.3.2.2 Institutional Controls • The ICobjectives are to ensure that:

• Groundwater is not used as drinking water; • Construction activities on Base do not interfere with required monitoring; • The site is not used for residential purposes; • Any proposed changes in land use are evaluated for consistency with acceptable risk­ levels; • Any intrusive work is conducted in a safe manner to ensure workers are protected; and • Any impacted groundwater that exceeds relevant regulatory criteria is appropriately handled.

The USAF is responsible for implementing, monitoring, maintaining, reporting on, and enforcing the ICs at FT-03. Under Alternative 3, the site will be designated as a "restricted use" area in the Base GIS. This designation prohibits activities such as residential development or use of groundwater. Additionally, groundwater use is currently restricted, as documented in the BGP, and procedures are in place to limit contact with groundwater through the issuance of permits to

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conduct subsurface work or activities. Records of the groundwater contamination will be kept in the Base GIS/environmental database. The restricted-use designation will remain in place until groundwater monitoring indicates that acceptable risk-levels are achieved. Any activity that is inconsistent with the IC objectives or use restrictions, or any other action that may interfere with the effectiveness of the ICs will be addressed by the USAF as soon as practicable. In no case will the process be initiated later than 10 days after the USAF becomes aware of the breach. The USAF will notify USEP A and MDE regarding how the USAF has addressed or will address the breach within 10 days of sending USEPA andMDE notification of the breach. The ICs can be modified as new data are analyzed; however, the USAF will not modify or terminate ICs, implementation actions, or modify land use without approval by USEPA and the MDE. The USAF will seek prior concurrence before any anticipated action that may disrupt the effectiveness of the ICs or any action that may alter or negate the need for Ies.

The following ICs are to be applied to FT-03:

• Any changes in land use, including construction of new facilities or additions to existing' facilities at FT-03 must be reviewed and approved through the Joint Base Andrews Facility Review Board, which interacts with the Community Planner using the BGP as a guide to land use issues. • The BGP will be updated to include restrictions at FT-03. All ERP sites and restrictions .' at Joint Base Andrews are identified in the BGP. Any proposed activity or construction on an ERP site requires an "ER Program Waiver to Construct" memorandum, approved and signed by USAF Headquarters, AFDW. • Signs will be posted at the site identifying FT-03 as a CERCLA site, summarizing the nature of contamination at the site, and stating that construction or excavation activities and groundwater use are not permitted within the area without written authorization by the USAF .. Contact information for the ERP project manager will also be included on the SIgnS. • Environmental personnel will review Work Orders and Dig Permits to ensure that any intrusive subsurface activities do not occur unless appropriate health and safety measures are implemented at FT-03. • Potable use of groundwater will continue to be prohibited at FT-03 (as it is across Joint Base Andrews, in general). COMAR 26.03.01.05 prohibits individual residents' or businesses from using private water supply wells when public water supplies are available; therefore, the installation of groundwater wells intended for potable use will not be approved by the state.

Monitoring of the environmental use restrictions and controls will be conducted annually by Joint Base Andrews. The monitoring results will be included in a separate report or as a section of •

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another environmental report, if appropriate, and provided to USEP A and MDE for informational purposes only. The monitoring reports will be used in preparation of the five-year reviews to •• evaluate the effectiveness of the remedy. The monitoring reports will evaluate the status of the ICs and how any IC deficiencies or inconsistent uses have been addressed. Joint Base Andrews is to notify USEP A and MDE 45 days in advance of any proposed land use changes that are inconsistent with IC objectives or the selected remedy.

7.3.3 Remedy Implementation

Groundwater samples have been collected at FT -03 approximately annually since at least 2002, and one post-ROD sample round (Match 2009) had been completed through April 2010 while the Tier I team discussed the appropriate locations for additional monitoring wells. The Tier I team agreed on additional locations in May2010, and ROD required sampling will resume as soon as the new monitoring wells are. installed .

. 7.3.4 System Operations/Operation and Maintenance

Installation ofremedia1 systems at FT-03 that,require operation and maintenance is notanticipated .

• 7.4 FT-03 PROGRESS SINCE LAST FIVE-YEAR REVIEW

This is the first five-year review for FT-03.

7.5 FT-03 FIVE-YEAR STATUS REVIEW PROCESS

'7.5.1 Community Involvement

TheUSAFhas'maintained a public involvement and information program for the ERP since 1990 and maintains an Administrative Record as required by CERCLA. The Administrative Record is maintained at the Environmental Flight, 3466 North Carolina Avenue, Joint Base Andrews. For the convenience of the public, a copy of the Administrative Record is maintained in an Information Repository located at:

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Community involvement activities for this five-year review consisted of publishing a notice in two local newspapers announcing the USAF's intent to perform the five-year review and providing information where and how the public could obtain additional information. The notice appeared in • the Prince George's County Gazette on December 3, 2009, and in the Capital Flyer on December 18, 2009. A copy of the notice is provided in Appendix A.

7.5.2 Document Review

The five-year review included review of relevant documents including the following:

• Draft Report for the Remedial Investigation FT-03? Fire Training Area 2 (Earth Tech, 2006) • Final Focused Feasibility Study at FT-03 (Tetra Tech, 2008) • Record of Decision, FT-03, Fire Training Area 2 (USAF and USEPA, 2008) • General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland (PBS&J,2009)

7.5.3 Applicable or Relevant and Appropriate Requirement Review

The ROD for FT-03 states that the only ARARs identified for the selected remedy are chemical­ specific MCLs and the state~s anti-degradation of groundwater quality requirement. No location­ • specific ARARs were identified. No ARAR tables were provided in the ROD. ARARs were not reviewed as part of the five-year site review. There have been no changes in the identified ARARs in the brief time since the ROD was signed in 2008.

7.5.4 Data Review

Only one round of post-ROD groundwater sampling results (March 2009) was available forreview at the time this report was prepared (Table 7.1). These data do not show exceedance of MCLs for benzo(a)pyrene or chromium. Because there is no MCL for naphthalene, this five-year review uses the risk-based value of 18 )lg/L developed for ST -10 as a basis for assessing whether naphthalene in groundwater presents a potential exposure risk. The value of 18 )lg/L was calculated to be protective of a future child resident at an HQ of 0.33 and, therefore, is a conservative measure of protectiveness. None of the March 2009 naphthalene data exceeded 18 )lg/L.

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Six rounds of pre-ROD data exist for the period spanning April 2002 through September 2008. These data show no exceedances of the benzo(a)pyrene or chromium MCLs. The arsenic MCL is • exceeded only once, in a 2002 sample (12 vs. 10 IlglL at MW04-FT03), but has been less than the MCL in six subsequent samples. Naphthalene does not exceed the risk-based concentration of 18 IlglL in any samples. In summary, between April 2002 and March 2009, there has been only one slight exceedance of an MCL in one sample, in 2002.

Appendix F contains the results of the Mann-Kendal1 Test using AFCEE's MAROS program. The program did not identifY any increasing or probable increasing trends.

7.5.5 Site Inspection

A LUC inspection was performed at FT -03 in January 2009 as part 'of a comprehensive LUC inspection at Joint Base Andrews CERCLA sites with RODs (MACTEC, 2009b). In addition, the FT-03 site was viewed on October 21, 2009. This later inspection confirmed general site conditions and land use assumptions.

7.5.6 Interviews • No interviews were conducted with community members in regard to FT-03. A public notice was published in two area newspapers in December 2009, indicating that the review process was underway and providing contact .information for questions or comments. No inquiries from the general public were received. Input on the review process was obtained from representatives of the USEPA, MDE,and Prince George's County through their participation in the Tier 1 partnering team and by their review of preliminary drafts of this document.

7.6 FT-03 TECHNICAL ASSESSMENT

The remedy for FT-03 is in the early stages of implementation; therefore, its function could not be fully assessed in accordance with USEP A guidance.

7.6.1 Question A: Is the remedy functioning'as intended by the decision documents?

Implementation of Institutional Controls and Other Measures. The USAF has prepared a draft " LUCIP for FT-03. When fmalized, it will be provided to the Joint Base Andrews Community

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Planner so that its requirements can be incorporated into the BGP. It is noted,however, that the BGP identifies FT-03 as an active ERP site (PBS&J, 2009). Therefore, a Waiver-to-Construct is required for all proposed construction at the site (AFI 32-1021). A Waiver-to-Construct means the • proposed construction has been evaluated with respect to site activity and environmental risks proposed by the construction and ultimate use of the facility. In addition, groundwater is prohibited from being used for potable purposes anywhere on Base (PBS&J, 2009), and COMAR 26.03.01.05 prohibits installation of new water supply wells. Because of these conditions, the major LUCs of the ROD are already in place.

Remedial Action Performance. Establishment of the fmal monitoring well network at FT -03 was delayed by discussion among the Tier I partners. Agreement on well locations was reached in May 2010, and installation of additional wells can now proceed. Historical data suggest that groundwater does not exceed MCLs or RBCs, and that additional actions to cleanup groundwater are not necessary at this time. A rebound of arsenic, chromium, and benzo(a)pyrene concentrations is not evident.

A great deal of the historical data for arsenic and benzo( a )pyrene in groundwater is reported as less than the reporting limit where the reporting limit exceeds potential, site-specific, RBCs. This • makes assessment of attainment of cleanup objectives difficult Improved laboratory reporting limits for future samples are recommended to confirm this assessment.

System Operations/Operation and Maintenance. No remedial systems have been, or are planned to be, installed at FT-03; therefore, assessment of system operations/operation and maintenance is not applicable.

Cost of System Operations/Operation and Maintenance. Remedial actions have not yet been completed at FT-03;. however, there were estimated costs of $54,000 in 2009 related to groundwater monitoring and well installation/repair, and preliminary development of a Remedial DesignlRemedial Action Work Plan.

Expected Progress Towards Meeting RAOs. Review of historical data suggests that groundwater does not exceed MCLs or RBCs, and that additional actions to cleanup groundwater are not necessary at this time.

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7.6.2 Question B: Are the exposure assumptions, toxicity data, cleanup levels, and remedial action objectives used at the time of the remedy still valid?

Land use at FT -03 has not changed since ROD signature and remains dedicated to recreational use (i.e., golf course). No changes in current or reasonably foreseeable future site conditions affecting remedy protectiveness were identified as part of this five-year review.

The toxicity data, cleanup levels, and RAOs for FT-03 were considered current at the signing of the ROD and have not been reviewed as part of this review. The risk assessment methodology and contaminant characteristic data used in the risk assessment were also considered current and were not reviewed.

7.6.3 Question C: Has any other information come to light that could call into question the protectiveness of the remedy?

No information has come to light during this review that could call into question the protectiveness of the remedy.

The exposure assumptions, toxicity data, cleanup levels, and RAOs for FT -03 were considered '. current at the signing of the ROD and have not been reviewed as part of this review.

No information has come to light during this review that could call into question the protectiveness of the remedy

7.7 FT-03 ISSUES

The following table summarizes the issues identified or Site FT-03 during this five-year review. The table only lists issues that affect current and/or future protectiveness.

Affects Protectiveness Issues (yIN) Current Future Analytical reporting limits for groundwater samples have exceeded cleanup criteria several times in the past, making assessment of remedy performance N y difficult.

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7.8 FT-03 RECOMMENDATIONS AND FOLLOW-UP ACTIONS

The following t~ble summarizes recommendations and follow-up actions identified for Site FT-03 during this five-year' review. The table only lists recommendations and follow-up actions for issues • that affect current and/or future protectiveness.

Follow-up Action Affects Recommendations 1Follow-up Party Oversight Milestone Protectiveness . Actions Responsible Agency Date (YIN) Current Future Make sure that requested sample quantitation limits allow USAF USEPA 12/31/2010 N Y comparison to cleanup criteria in future sampling events.

7.9 FT-03 PROTECTIVENESS STATEMENT

The selected remedy for FT-03 is expected to be protective of human health and the environment upon completion, and, in the interim, exposure pathways that could result in unacceptable risks are being controlled. ( 7.10 FT-03 NEXT REVIEW •

FT-03 is a statutory site that reqUITes ongomg five-year reVIews. The next reVIew will be performed within five years of the completion of this five-year review report. The completion date' is the date of the signature shown on the signature cover attached to the front of this report.

7.11 FT-03 REFERENCES

CH2M Hill, 2005. Basewide Ecological Risk Assessment, Step 7, Andrews Air Force Base, Maryland, March.

Dames & Moore, Inc., 1992. Technical Memorandum for the FT03 Site, Andrews Air Force Base, Maryland, prepared for Hazardous Waste Remedial Action Program, Martin Marietta Energy Systems Inc. Oak Ridge, Tennessee under General Order No. 70B-99786C Work Release No. K-06, October.

Earth Tech, 2006. Draft Report for the Remedial Investigation FT-03, Fire Training Area 2 Andrews Air Force Base, Maryland, October.

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ES (Engineering Science), 1985. Phase 1 Records Search, Installation Restoration Program, Andrews AFB, Maryland,prepared for the U.S. Air Force, AFESCIDEV, and HQ MACIDEEV, June.

• Glenn and Sadler Associates, Inc., 1995. Soil Investigation at FT-03 for the Golf Course Addition, Andrews Air Force Base, Maryland, NAF Projects: AJXF955001, A&E Contract: N62470­ 93-D-4049, August 28.

IT Corporation, 2002~ Preliminary Groundwater Sampling Results, FT~03.

MACTEC, Inc., 2003. Preliminary Groundwater Sampling Results, FT-03. - PBS&J, 2009. General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland, December.

Tetra Tech, Inc., 1996. Final ERP RCRA Facility Investigation/Correction Measures Study Technical Report, Andrews AFB, Maryland, prepared for the Air Force Center for Environmental Excellence, HSCIPKCVCB Headquarters Human System Center (AFMC), Brooks Air Force Base, Texas, April.

Tetra Tech, Inc., 2008.. Final Focused Feasibility Study at FT-03 Andrews Air Force Base, Maryland, January.

USAF and USEPA (U.S. Air Force and U.S. Environmental Protection Agency-Region III) 2008. Record of Decision, FT-03, Fire Training Area 2, Andrews Air Force Base, Maryland, October. • USDA (U.S. Department of Agriculture), undated. Soil Survey of Andrews Air Force Base. USGS (U.S. Geological Survey), 1989. Andrews Air Force Base Data Summary for Site 7 - FT2 Fire Training AJea 3.

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• Joint Base Andrews - First Five- Year Review November 2010 MACTEC Engineering and Consulting. Inc. Project Number 3350092494 (Revised March 2011)

8.0 LF-05 FIVE-YEAR STATUS REVIEW

The ROD for LF-OS, Leroy's Lane Landfill, was signed in July 2009. Remedial actions were • begun at LF-OS in the summer of 2009 and were ongoing at the time this five-year report was prepared. Therefore, this review isa status review that does not fully address all the review elements in USEPA's Comprehensive Five-Year Review Guidance (USEPA, 2001). Because hazardous substances, pollutants, or contaminants will remain at the site above levels that allow for unlimited use and unrestricted exposure, this isa statutory review under CERCLA.

Information in Subsections 8.1, 8.2, and 8.3 is based primarily on material presented in the ROD (USAF and USEP A, 2009).

8.1 LF-05 DESCRIPTION AND CHRONOLOGY

LF-OS occupies approximately 12 acres southeast of East Perimeter Road at Joint Base Andrews (Figure 8.1). The site was used as a disposal area from the late 19S0s until the 1980s for Base­ generated wastes including sludge from the Base wastewater treatment plants, liquid solvents, waste oils, general refuse, construction rubble, and fly ash. In the 19S0s and 1960s,sludge from the Base wastewater treatment plant was land applied on the eastern side of LF-OS. Between 1960 • and 1972, solvents, strippers, and waste fuel were disposed of at this site. Other wastes disposed of at LF -OS between the 1960s and the 1980s included, but were not limited to, toluene, waste oils, PD-680, brake and transmission fluid, empty cans and containers from golf course maintenance, paint cans, paint, carbon remover, hydraulic fluid, cleaning solvent, 1,1, I-trichloroethane, primer, methyl ethyl ketone, and thinner. During .theearly 1960s through the mid-1970s, a 2- to 3-acre pit located in the southeastern portion of LF-OS was used for disposal of liquid wastes, dilute process waste, and waste oils. In the mid-1970s,two 2S,000-gallon USTs were installed on the northwest side of LF-OS to replace the waste oil pit. The tanks were pumped out periodically and removed in 1986. Municipal wastes were disposed of at LF-OS from the early 1960s through the mid-1970s (Earth Tech, 2007).

Wastes were disposed of in approximately lO-foot-deep trenches, liquid waste disposal pits, and sludge disposal areas. In addition, USTs were used to store waste oil at the site. Two 2S,000­ gallon USTs, that were previously located near the northwest portion of the landfill, have been removed and disposed.

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During the mid to late 1980s, the Base discontinued using the landfill and covered portions of it with clean fill material. The covered landfill was subsequently used as an open temporary storage area for construction materials such as lumber, sand, and concrete and plastiC sewer and storm • piping. Scrap rrietal from various Base construction projects and excavated soil from a runway extension project are also found at the landfill . .All storage activities were conducted on the ground surface. No subsurface activities are performed.

LF-OS is an ERP site that is in the CERCLA process at Joint Base Andrews. A chronology of remedial studies, investigations, and reports at LF-OS is presented below.

• 1985: Phase I Record Search (Engineering Science, 1985) • 1988 to 1990: Stage I, Environmental Restoration Program Remedial InvestigationlFeasibility Study (USGS, 1990) • 1986: Two 2S',000-gallon USTs removed from site (Earth Tech, 2006) • . 1991-1992: Groundwater Contamination Survey (Dames & Moore, 1992) • 1994: Technical Memorandum of Findings (Dames & Moore, 1994) • 1995: Draft Remedial!InvestigationlFeasibility Study (EA Engineering and Science, 1~~ .

• 1999: Quarterly Groundwater Sampling (MAC'r~C; 1999) • 2000 to 2001: Seep Sampling (pGCHD,2001; as referenced in USAF andUSEPA, 2009) • 2001: Light Detection and Ranging Survey (Earth Tech, 2006) • 2001 to 2006: Final Remedial Investigation (Earth Tech, 2006) • 2006: Final Groundwater Flow Model Report (Booze Allen Hamilton, 2006) • 2006: Pre-Design Investigation (CH2M-Hill, 2006) • 2006 to 2007: Feasibility Study (Earth Tech; 2007) • 2008: Feasibility Study Addendum (DRS, 2008a) • 2008: Revised Ecological Evaluation of Sediment in the Vicinity of Landfill OS (DRS, 2008b) • 2009: Record of Decision (USAF, 2009)

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8.2 LF-05 BACKGROUND • 8.2.1 Physical·Characteristics Prior' to the start of landfill remediation activities in the fall of 2009, the LF -OS landfill had uneven, relatively gently . undulating topography. The landfill surface was generally covered with soil, grass, weeds, isolated bushes, and some small stands of trees. The landfill is bordered on the northeast and southeast by the Base. boundary fence, and on the north and east by forested wetlands.

The drainage from the LF-OS landfill exits the Base primarily via two unnamed tributaries, one that exists to the northeast of LF-OS, and one that exists to the southwest -of LF-OS. Both unnamed tributaries ultimately flow to Piscataway Creek, which is located approximately 3,200 feet southwest of the landfill. Piscataway Creek is designated in the COMAR 26.08;02.08 as a Use II category, which includes water bodies used for recreation, fishing, aquatic life and wildlife, and supports estuarine and marine aquatic life and shellfish harvesting-.

Within the LF-OS landfill, depth to groundwater varied from 11.6 to 27.S feet bgsas recorded during the RI. On the adjacent off-Base properties (Parcels A and B), the depth to groundwater • varied from 2.4 to 10.2 feet bgs and from 14.1 to 18.2 feet bgs, respectively. In the vicinity of the LF-OS landfill, groundwater flows east and southeast at an estimated seepage velocity of S.OS feet per day in the upper portion and 2.26 feet per day in the lower portion of the Upland Deposits (Earth Tech, 2007).

8.2.2 Land and Resource Use

The LF-OS landfill occupies approximately 12 acres on the southeast side of Joint Base Andrews, east of East Perimeter Road and adjacent to Building 249S, the small arms firing range located at the northwest comer of LF-OS (see Figure 8.1). The site's industrial land use designation is not expected to change in the future (PBS&J, 2009). The landfill is bordered on the northeast and southeast by the Base boundary fence" and on the north and east by forested wetlands. Land use off-Base, adjacent to Joint Base Andrews, includes light industrial, commercial, and undeveloped parcels. An undeveloped property, (identified as "Parcel A") and several commercial properties are located east of the landfill. Another property (identified as "Parcel B"), a fonner sand and gravel quarry which operated as a wholesale automobile salvage facility between 2001 and 2004, is • 146 P:IProjectslAndrews AFB EnvironmentalIFive-year reviewsl4_0 _ OeliverablesI4_I_ReporlslFinallAndrewsAFB _5-Yr Review _Revised March 2011.doc loint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

located to the south of the landfill. Currently, 'Parcel B is cleared of any remnants associated with thi,s salvage operation and is vacant (USAF, 2009). No endangered or rare plants have been identified at the LF-OS landfill or areas adjacent to the landfill (USAF, 2009). •

There are no potable water supply wells located at Joint Base Andrews, including LF-OS, and none within Y2 mile of LF-OS (USAF, 2009). There is no current use or exposure to groundwater. Groundwater at LF-OS is not expected to be used for such purposes in the future. Joint Base Andrews is currently served by public water supplied by WSSC, and, according to COMAR 26.03.01.0S, wells cannot be installed in areas where public water infrastructure is available.

No areas of archaeological or historical significance have been identified at LF-OS.

8.2.3 History of Contamination

8.2.3.1 Soil Sampling Results

Results of RI samples collected in 2002 and 2003 (Earth Tech, 2006) indicated the presence of pesticides, P AHs, PCBs, fuel constituents (jet fuel, diesel, and gasoline), arsenic and lead at elevated concentrations at various depths in soil at LF-OS.Soil samples were collected from 36 soil borings and four monitoring wells on-site and downgradient during the RIlFS field investigation at • LF-OS. During the Earth Tech investigation, 213 soil samples plus 22 duplicate (quality assurance) soil samples were collected at LF-OS. The distribution of PAHs,PCBs, fuel constituents, arsenic, . and lead was scattered throughout the landfill and adjacent to the landfill; pesticides were concentrated in the southeastern portion of the landfill only.

Based on the HHRA, the primary contaminants that contribute to potential risk to human receptors are VOCs and chromium in subsurface soil. Vapor from VOCs in the subsurface soilalso presents potential risk.

Results of pre-design investigation samples collected in 2006 (CH2M Hill, 2006) indicated the presence of non-aqueous phase liquid in soil at the west-central portion of the LF-OS landfill in boreholes SB20S-11 and SB20S-12. This hot spot consists ofVOCs including methylene chloride, TCE, PCE, and SVOCs. This hot spot extends nine feet bgs, is approximately 30 feet wide by 60 feet long, but is smaller than the size that was inferred in the RI report.

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8.2.3.2 Surface Water Sampling Results ,I • Surface water samples were collected from 22 locations at LF-OS in 2002 and 2003 during two separate RI sampling events. Two of the 22 surface water sample locations were inside the landfill. The other 20 samples were collected from outside the landfill boundary in areas of standing water. One event occurred during the spring to represent a wet season, and the second event occurred during the fall to represent the dry season. The surface water bodies at LF-OS are intermittent in nature and are present only during times of moderate to heavy rainfall. Consequently, not all locations contained water during the two rounds of surface water sampling. In total, forty surface water samples and four duplicate surface water samples were collected at LF-OS.

Based on the HHRA, the surface water does not pose a potential threat to human receptors.

8.2.3.3 Sediment Sampling Results

Forty-four sediment samples and eight duplicate sediment samples were collected at LF-OS-in 2002 and 2003 during the RI. The duplicate samples were collected for sample quality control purposes. Samples were collected near locations where surface water samples were collected. Sediment samples were collected concurrently during the two surface water sampling events described • above.

Based on the HHRA, sediment does not pose a potential threat to human receptors; ho~ever, a _potential risk to the ecology is posed primarily by PCBs, P AHs, and metals. In spring 2008, additional sediment samples were collected and the results were reviewed by BTAG to delineate the extent of sediment that poses an ecological risk to receptors at LF-OS.

"8.2.3.4 Groundwater Sampling Results

Sixty-seven groundwater samples were collected from 34 new and existing monitoring wells during the RI field investigation in 2003 and 2004. The sample results indicated that VOCs, PCBs, and metals were detected in shallow groundwater at the landfill in concentrations ranging from less than their MCLs to four times their MCLs, depending on the analyte. A VOC plume, consisting primarily of benzene and chlorobenzene, was detected along the eastern and southern boundary of the landfill and at Parcels A and B. Vinyl chloride and cis-l,2-DCE were also detected in the

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northern portion of Parcel A, but were not observed within the LF-05 landfill or at Parcel B, potentially indicative of biodegradation of the chlorinated VOCs in this area (USAF, 2008). • Based on the HHRA and comparison to MCLs, the primary contaminants that contribute to potential risk to a future resident are chlorobenzene, vinyl chloride, and PCBs.

8.2.4 Initial Response

Previous responses at LF-05 include removal of two 25,000-gallon USTs from the site in 1986, and

covering portions ofLF-05 with'clean fill aft~r discontinuing disposal activities in the mid- to late­ 1980s.

8.2.5 Basis for Taking Action

The HHRA identified unacceptable risks for future on-Base and off-Base residents from exposure to VOCs and metals in subsurface soil, and to VOCs and PCBs in groundwater. Although groundwater at LF-05 currently is not being used for potable supply or any other purpose, it is possible that, in the future, the groundwater could become a resource for residential use.

The ecological risk analysis overall shows no threat to the environment; however, one area • designated by sample location SD-15 will be remediated because of sediment containing an anomalously high concentration of lead .

.The ROD concluded that remedial action was required to protect human health or welfare from actual or potential releases of contaminants in subsurface soil on Base, and groundwater both on­ and off-Base within specific areas of LF-05.

8.3 LF-05 REMEDIAL ACTIONS

The ROD for LF-05 was signed in July 2009 documenting the selected remedy for cleanup of groundwater associated with known releases at the Site (USAF, 2009).

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8.3.1 Remedial Action Objectives • . Based on an evaluation of site conditions, an understanding of the contaminants, the results of the risk assessments, and an analysis ofARARs, the ROD identified the following RAOs for LF-OS:

Landfill Contents (including landfIll Hot Spot)

• Reduce the infIltration of precipitation into the waste material to reduce the quantity of leachate produced. • Prevent the erosion of existing cover material to prevent exposure of buried waste material (includes storm water and cover management activities). • Prevent access to waste material. • Mitigate off-site I?ignition of landfill gases. • Reduce the potential for migration of contaminants from landfill hot spots in soil and groundwater. • Mitigate off-site migration of groundwater contamination.

Off-Base Sediment (adjacent to landfIll)

• • Remove sediment posing unacceptable risk to ecological receptors.

On-Base groundwater (described as landfill leachate in the FS [Earth Tech, 2006])

• Reduce the quantity of leachate generated. .• Prevent, through groundwater treatment, the continued migration of landfill leachate into on and off-Base groundwater.

Off-Base Groundwater

• Prevent continued off-Base migration of contaminated groundwater. • Remediate off-Base groundwater to acceptable contaminant levels.

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COCs and cleanup concentrations are listed in the following table.

Contaminants of Concern and Cleanup Criteria at LF-05 • Cleanup Criterion Contaminant of Concern (pJ.glL) Basis for Selection Groundwater Chlorobenzene 100 11 gIL MCL PCBs 0.51lg!L MCL Vinyl chloride 21lgIL MCL Sediment Lead 400 mg/kg Risk based Landfill Contents Not applicable Not applicable

8.3.2 The Selected Remedy

The selected remedy at LF-05 was FS AlternatIve 7: RCRA Subtitle D Single-Barrier Cap, Hot Spot Containment, Removal of Contaminated Sediment, Funnel and Gate with permeable reactive barrier (PRB) for Treatment ofOn:'Base groundwater, and In-Situ Groundwater Treatment of Off­ Base Groundwater by lnjection of Appropriate SubstrateslReactants. The remedy was selected in recognition of the following site circumstances: • • There is no current or likely future unacceptable risk presented because the land use is expected to remain as industrial. • Future potable use of shallow groundwater at the site is extremely unlikely because drinking water wells are prohibited by State ofMaryland regulation at this location. • Groundwater poses a potential ingestion risk to future off-Base residential users.

The remedy addresses exposure to landfill contents,sediment contamination, and groundwater contamination. The major components of the selected remedy consist of the following:

• Installation of a RCRA Subtitle D Single-Barrier Cap • Containment ofthe hot spot • Off-site disposal for sediment containing hazardous waste or on-site consolidation of non­ hazardous contaminated sediment prior to capping, in compliance with RCRA land disposal restrictions • Funnel and gate with PRB for treatment of on-Base groundwater • In-situ groundwater treatment of off-Base groundwater by injection of appropriate • substrates or reactants 151

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• Long-term monitoring • Implementation of ICs for the landfill and groundwater until cleanup criteria are achieved • .for groundwater

The primary cOJ?ponents of Alternative 7 are:

• Installation of a RCRA Subtitle D Single-Barrier Cap • Containment of the hot spot • Off-site disposal for sediment containing hazardous waste or on-site consolidation ofnon­ hazardous contaminated sediment prior to capping, in compliance with RCRA land disposal restrictions • Funnel.and gate with PRB for treatment of on-Base groundwater • In-situ groundwater treatment of off-Base groundwater by injection of appropriate substrates or reactants • Long-term monitoring • Implementation of ICs for the landfill and groundwater until cleanup criteria are achieved for groundwater

8.3.2.1 Landfill Cap

• Approximately 10.5 acres of the LF-05 landfill will be covered with a RCRA Subtitle D single barrier cap, consisting of a vegetative cover.and, earthen and synthetic materials. An additional 1.5 acres (approximately) will be covered by an asphalt cap, and earthen and synthetic materials. The asphalt will be used for temporary storage (i.e., industrial use). The area covered by the RCRA Subtitle D single barrier cap may increase based on the fmdings of the pre-remedial design investigation study.

The RCRA Subtitle D single barrier cap consisting of a vegetative cover and earthen and synthetic material will comprise the following (from top to bottom):

.• A minimum of 6 inches oftopsoil on which vegetative grasses will be planted • A geotextile fabric • A minimum of 18 inches of earthen cover that will be compacted to retard percolation • A drainage grid/net installed to create a preferential flow path for any water that does infiltrate through the earthen layers, and allows water to drain away from the impermeable liner • 152 P:IProjeclSlAndrews AFB EnvironmentallFive-year reviewsl4.0 _ DeliverablesI4.1_ ReportslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, fllc. Project Number 3350092494 (Revised March20ll)

• A minimum thickness of 20-mil or equivalent impermeable flexible membrane liner (FML), or an equivalently inlpermeable geosynthetic clay liner (GCL) • A compacted sub-base layer of soil that serves as an appropriately-sloped and protrusion­ free base for installation of the FML (or GCL) • .' Approximately one gas vent per acre to ensure landfill gasses are not migrating off-site and off-Base

The gases generated at the source are not sufficient to cause a health risk or flammability concern (CH2M Hill, 2006) and will be passively ventilated to the atmosphere. Gas vents near the hot spot I area will be periodically monitored to determine VOC concentrations vented to the atmosphere and , to determine if air emission controls are necessary in accordance with COMAR 26.11.06.06.

The RCRA Subtitle D single barrier cap consisting of an asphalt cover and earthen and synthetic material will consist of the following (from top to bottom):

• A minimum of 3 inches of asphalt concrete mix over which a tack coat will be applied; • A minimum of 12 inches ofbase aggregate; • An optional.geotextile layer to separate aggregate from a drainage grid; • A drainage grid that allows infiltrated water to drain away from the impermeable liner; • A minimum thickness of20-mil or equivalent FML (or GCL); and • A compacted sub-base layer of soil that serves as an appropriately-sloped and protrusion­ free base for installation of the FML (or equivalent impermeable GCL).

The asphalt cap area will be designed to function as a parking and equipment storage area.

A storm water management system will be included as part of theRCRA Subtitle D single barrier cap design. Surface runoff from the cap will be collected and channeled to the existing wetlands and tributaries in the vicinity of the LF-05 landfill that ultimately drain toward Piscataway Creek. A security road will be constructed along the southern and eastern perimeter of the landfill cap.

The objectives of the landfill cap are to:

• Reduce the inftltration of precipitation into the waste material to reduce the quantity of leachate produced • Prevent the erosion of existing cover material to prevent exposure of buried waste material (includes storm water and cover management activities) 153 , P:\Projects\Andrews AFB Environmental\Five-year reviewsl4.0 _ Deliverablesl4. 1_ ReportslFinal\AndrewsAFB _5-Yr Review _Revised March 201 I.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

• Prevent access to waste material • Mitigate off-site migration of landfill gases • • Reduce the potential for migration of contaminants from the hot spot • Mitigate off-site migration of groundwater contamination

8.3.2.2 Hot Spot

The hot spot (Earth Tech, 2006), consisting of relatively highly contaminated material, is near the central portion of the landfill area. The hot spot was the focus of a follow-on study (CH2M Hill, 2006), which identified the dimensions of the hot spot through specialized sampling techniques. The hot spot is now defmed as approximately 30 feet wide by 60 feet long with a depth of· contamination of 9 feet. The follow-on study determined the hot spot to be a source of contamination that constitutes a principal threat,but that is distinctly smaller than the area inferred in the RI and shown on RI figures. The planned footprint of the RCRA Subtitle D single barrier cap fully covers this hot spot area. The cap ~ill prevent infiltration of precipitation through the hOt spot and, thereby, will prevent production of leachate from the hot spot, which has contaminated groundwater beneath the landfill.

• 8.3.2.3 Sediment and Soil Wetland sediment containmg lead concentrations greater than 400 mg/kg will 'be excavated and sampled. If sample results indicate the excavated sediment contains a RCRA hazardous waste,it will be disposed off-site at a permitted facility. Otherwise, the excavated sediment will be consolidated within the area to be covered at the LF-05 landfill prior to the installation of the RCRA Subtitle D single barrier cap. Clean backfill will replace the excavated sediment. Criteria for excavation and disposal of wetland sediment was developed between Joint Base Andrews and the USEPA BTAG based on review of sample results collected ill spring 2008 during the pre­ remedial LF-05 design activities (URS, 2008b).

. \ Additionally, the area southwest and adjacent to the landfill was evaluated in spring 2008 for the presence of disposed debris and soil. The investigation included trenching and field observations which indicated this area (approximately 1.4 acres) was used for some surface dumping of soil and other waste material. Any such material found in this area will be either excavated and consolidated within the LF-05 area to be capped prior to the cap installation, or the LF-05 cap will be extended to cover the area containing soil and debris southwest of the previously identified 12­ • 154 P:\Projects\Andrews AFB EnvironmentallFive-year reviewsl4.0 _DeliverablesI4.I_ReportslFinal\AndrewsAFB _ 5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project. Number 3350092494 (Revised March 2011)

acre boundary of the landfill (Earth Tech, 2006). The remedial design will specify, based on cost effectiveness, whether excavation or cap expansion is preferred for addressing any such areas identified to the southwest. Contaminated soil from Site SS~27 and soil from other areas at Joint • Base Andrews also may be excavated and consolidated within the area to be capped at the LF-05 landfill pending results of the soil samples. No soil that exceeds RCRA land disposal restrictions will be placed at LF -05. Imported soil will be used to establish grades of the landfill in accordance . with the remedial design.

All of the landfill contents will be covered with a RCRA Subtitle D single-barrier cap. This cap will be compliant with COMAR 26.04.07.21, which addresses Closure of permitted municipal solid waste landfills by construction of a cap.

8.3.2.4 On-Base Groundwater

On-Base groundwater will be remediated by construction. of impermeable Clay walls. (slurry walls) that serve as a funnel to redirect flow to a PRB, constructed to. serve as a gate containing a treatment medium. The treatment medium removes contaminants as the groundwater flows through the gate. Thus, the PRB is permeable to groundwater flow while serving asa barrier to • movement of contaminants to off-Base areas. The slurry wall and PRB will extend downward into the Calvert Formation,a locally impermeable underlying geologic unit. A substrate or reactant will be injected initially and added periodically as needed into the PRB to treat groundwater contaminants. The appropriate substrate or reactant to be injected into the PRB will be determined based on the groundwater monitoring performed in support of the groundwater remedial design conducted in fall 2008. The funnel and gate system will provide treatment and prevent lateral migration of groundwater.. The locations and sizes of the slurry walls and the PRB will be . optimized based on review of geological cross sections showing the subsurface lithology near the downgradient edges of the former landfill and groundwater modeling results (CH2M Hill, 2006).

8.3.2.5 Off-Base Groundwater

Based on data collected during the RI, off-Base groundwater has contaminant concentrations of approximately two to three times applicable Cleanup criteria (Earth Tech, 2006). A substrate or reactant appropriate for treatment of the off-Base groundwater contaminants will be injected into the subsurface. The type of substrate or reactant will be detemiined based on 'groundwater monitoring performed in support of the groundwater remedial design (fall 2008). 155 • P:\Projects\Andrews AFB Environmental\Five-year reviewsI4.0_DeliverablesI4.I_ReportsIFinal\AndrewsAFB_5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, inc. Project Number 3350092494 ( (Revised March 2011)

8.3.2.6 Long Term Monitoring and Maintenance • A groundwater monitoring and data management program will be established to provide the necessary information to monitor progress toward RAOs and ultimately to conftrm the basis for reaching cleanup criteria. The goal of the groundwater monitoring program. is to assess performance of the RCRA Subtitle D single-barrier cap, the funnel and gate on-Base groundwater treatment system, and the ongoing effect treatment of COCs in off-Base groundwater. The exact locations for groundwater monitoring will be selected during the design of the groundwater remedy. The long-term groundwater monitoring data will be used to determine the degradation rates and mass reductions of·COCs. For these purposes, samples will be analyzed for VOCs and metals. Field measurements will include temperature, conductivity, pH, ORP, and dissolved oxygen. The measurements of VOCs, metals, and fteldparameters will be used to assess the aquifer's capacity for degradation of the COCs at LF-OS. The monitoring program can be refilled as new data are analyzed.

8~3.2.7 Institutional Controls

ICs are to be implemented at LF-05 by Prince George's County and Joint Base Andrews within the area shown on Figure 8.1. The lCs described in this ROD will remain in place until the RAOs have been achieved, but can be modifted pursuant to CERCLA, the NCP, and the ROD for the site as new data are analyzed.

The objectives of the ICs at LF-OS are the following:

.• Ensure no potable use of impacted shallow groundwater at the site until MCL'S are met and acceptable risk levels are achieved based upon cumulative risk in order to limit exposure to groundwater contaminants; • 156 'P:lProjectsIAndrews AFB EnvironmentalIFive-year reviewsI4.0_DeliverablesI4:I_ReportsIFinallAndrewsAFB_S-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

• Ensure that excavation, construction or any similar activities occurring within the IC area do not reduce performance of the remedy, interfere with the ability to undertake required environmental monitoring, or cause the plume to spread off~Base; • Ensure that workers performing any excavation, construction or any similar activities are • protected from exposure producing an unacceptable risk by implementation of a health and safety plan; • Ensure that no activities degrade, or in any way cause, the RCRA Subtitle D cap to fail to perform as specified in the ROD or fail to comply with ARARs, inCluding State of Maryland landfill Closure requirements, COMAR 26.04.07.21B and E; • Ensure that the remedy, inCluding the groundwater monitoring wells and slurry walls, are protected from damage by undertaking annual inspections; • EnsUre that any impacted soil and groundwater exceeding relevant regulatory criteria are properly sampled, handled, and disposed of during any construction and sampling .activities; .• Ensure no residential land use occurs until site conditions allow for unlimited use and unrestricted exposure; and

• Ensure that a written advisory is provid~d to owners of property off-Base stating that safety precautions should be undertaken in the event of excavation, construction, or soil disturbance to ensure that environmental conditions do not pose an unacceptable risk to workers.

The groundwater plume protrudes beyond the Base boundary onto private properties. Implementation of· state regulations and county ordinances by Prince George's County, whiCh • apply countywide, will be relied upon to protect private property owners and the public from groundwater that may contain hazardous substances,pollutants, or contaminants. These off-Base ICs implemented by the county inClude:

.• Review of groundwater well permits to ensure potability of groundwater within and near the plume, in accordance with COMAR 26.04.04.09; • Prohibit issuance of a well permit to individual residents or businesses for private water supply wells when public water supplies are available, as in the case of LF-OS, in accordance with COMAR 26.03.01.0SA; and • Review of plans for development, inCluding construction of new buildings or additions to . existing buildings, through the Permits and Review Division of Prince George's County Department of Environmental Resources (pGCDER), in accordance with Prince George's County Code, Subtitle 4, Sections 4-270 through 4-31S. Requirements for vapor intrusion monitoring and mitigation will be evaluated by PGCDER for buildings or additions to existing buildings proposed for construction over the off-Base groundwater plume.

Currently, Joint Base Andrews and all residences and businesses located within the vicinity of LF­ OS receive potable water from the 10c~1 water authority, wssc. The use of groundwater at off­ 157 • P:IProjects\Andrews AFB EnvironmentallFive-year reviewsl4.0 _ DeliverablesI4.1_ ReportslFinal\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

Base properties is currently restricted, as documented in the Prince George's County Ten Year Water and Sewer Plan.

The USAF is responsible for implementing ICs on Base at LF-OS. The landfill cap and security road area will be designated as a "restricted use" area in the Base GIS. This designation prohibits activities such as residential development or potable use of groundwater., Additionally, groundwater use is currently restricted, as documented in the BGP, and procedures are in place to limit contact with groundwater through the issuance of dig permits and other protective measures. Records of groundwater contamination will be maintained in the Base GIS/environmental database. The restricted-use designation will remain in place until groundwater monitoring indicates that the RAOs have been met on Base at LF-OS.

The USAF is not to modify or terminate LUCs, implementation actions, or modify land use without approval by USEPA and MDE. The USAF is to notify USEPA and MDE 4Sdays in advance of any proposed land use changes that are inconsistent with LUC objectives or the selected remedy.

Other ICs applying to LF-OS, onBase, are the following:

• • Review and approval of any proposed changes in land use, including construction of new facilities or additions to existing facilities at LF-OS by the Joint Base Andrews Facility Review Board, which interacts with the Community Planner using the BGP as a guide to land use issues. The purpose ofthe review is to ensure consistency with the prohibition of construction of any facility, building, or any structure that would have a negative impact on the remedy in meeting the RAOs. • Inclusion of the restrictions at LF-OS in the BGP. All ERP sites andrestrictions at Joint Base Andrews are identified in the BGP. Any proposed activity or construction on an .ERP site requires an "ERP Waiver to Construct" memorandum, approved and signed by the USAF. • Review of proposed construction actlvitles at LF-OS by Joint Base Andrews Environmental Flight through the following processes: ElAP, NEPA Design Reviews of Proposed Construction, review of routine Work Orders that involve alterations to facilities, and review of Dig Permits. • Posting of signs at the site identifying LF-OS as a CERCLA site. The signs will state that no construction or excavation activities, and no groundwater use or withdrawal,is permitted within the area without written authorization by the USAF. Contact information for the ERP project manager will also be included on the signs. • Restriction of access. Access to the LF-OS site is and will be limited to Base personnel and its contractors and is enclosed by asecurity fence controlled by Joint Base Andrews security personnel. • 158 P:IProjects\Andrews AFB EnvironmentalIFive-year reviewsl4.0 _ DeliverablesI4.1_ ReportslFinal\AndrewsA FB_5-Y r Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting. Inc. Project Number 3350092494 (Revised March 2011)

• Continued prohibition of potable use of groundwater. Potable use of groundwater is prohibited at LF-OS and at Joint Base Andrews in total. COMAR26.03.01.0SA prohibits issuance of a permit to individual residents or businesses for private water supply wells when public water supplies are available; therefore, the installation of groundwater wells .' intended for potable use will not be approved atthe site. Review of Work Orders and Dig Permits by Joint Base Andrews Environmental staff also will ensure that potable groundwater wells will not be installed at LF-OS. • Provision ofregular updates to the Prince George's County Health Department (pGCHD), PGCDER, and MDE regarding the extent of the groundwater contamination and the required distance of wells and dewatering trenches from the edge of known plwneareas for safe groundwater usage. . • Notification of the USEPA and MDE regarding anyon-Base activity that impacts IC . objectives.

The USAF and Prince George's County commit to work cooperatively to address any activity that may interfere with the effectiveness of the ICs or is inconsistent with the IC objectives or use restrictions as soon as possible. The USAF or Prince George's County, as appropriate, will notify the USEPA and MDE regarding any activities that impact IC objectives or the remedy.

8.3;3 Remedy Implementation

Remedial construction began at LF-OS.in late summer 2009 and was ongoing at the time this report was prepared. It is anticipated that landfill cap construction and PRB installation will be completed in spring 2010. A list of completed construction milestones through December 2009 is listed below.

Construction Milestones at LF-05 Construction Milestone Completion Date Temporary security fence installation August 20, 2009 Existing security fence removal August 27, 2009 Mobilization September 2, 2009 Phase I ESC control installation November 24,2009 159 • P:\Projects\Andrews AFB EnvironmentallFive-year reviews\4.0_ Deliverables\4.1_ReportslFinal\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

Construction Milestones at LF-OS Construction Milestone Completion Date Clear and grub (Phase 1 Area) October 14,2009 • Work platfonn construction November 10,2009 Slurry wall and PRB installation December 9,2009

8.4 LF-05 PROGRESS SINCE LAST FIVE-YEAR REVIEW

This is the first five-year review for LF-05.

8.5 LF-05 FIVE-YEAR STATUS REVIEW PROCESS

8.5.1 Community Involvement

The USAF has maintained a public involvement and information program for the ERP since 1990 and maintains an Administrative Record as required by CERCLA. The Administrative Record is maintained at the Environmental Flight, 3466 North Carolina Avenue, Joint Base Andrews. For

the convenience of the public, a copy o~ the Administrative Record is maintained in an Information Repository located at:

Prince George's County Memorial Library-Surratts-Clinton Branch. • 9400 Piscataway Road Clinton, MD 20735 \

Community involvement activities for this fIve~year review consisted of publishing a notice in two local newspapers announcing the USAF's intent to perform the five-year review and providing information where and how the public could obtain additional information. The notice appeared in the Prince George's County Gazette on December 3, 2009, and in the Capital Flyer on December 18,2009. A copy of the notice is provided in Appendix A.

.8.5.2 Document Review

The five-year review included review of relevant documents including the following:

• Final Report for the Remedial Investigation for LF-05, Leroy's Lane Landfill (Earth Tech, 2006) • Final Feasibility Study for LF-05, Leroy's Lane Landfill (Earth Tech, 2007) • Addendum to the Final Feasibility Study for LF-05, Leroy's Lane LandfIll (URS, 2008a) • 160 P:IProjectslAndrews AFB EnvironmentalIFive-year reviewsl4.0 _DeliverablesI4.1_ ReportslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

• Record of Decision, LF-05 Leroy's Lane Landfill (USAF and USEPA, 2009) • General Plan Update - Joint Base. Andrews-Naval Air Facility Washington, .Maryland (PBS&J, 2009) •

8.5.3 Applicable or Relevant and Appropriate Requirement Review

The ROD does not identify specific ARARs for LF-05, but makes the following statement:

"The selected remedy complies with all chemical-specific ARARs because groundwater will be remediated to achieve MCL-based cleanup criteria. The location-specific ARARs will be attained with engineering controls to minimize exposure to workers from contaminated sediment, landfill contents, and contaminated groundwater. during sediment excavation and disposal, construction of landfill cap and funnel-and-gate PRB [permeable reactive barrier] system, well installation, substrate/reactant injection, and monitoring. In addition, VOC from gas vents will be monitoring as.required for sites located in air quality non-attainment areas. The selected remedy complies with all action specific ARARs by implementation of engineering controls to minimize damage to sensitive habitats, as well as not to violate noise control regulations."

ARARs were not reviewed as part ofthis five-y~ar site review.

8.5.4 Data Review

No data review was performed. •

8~5.5 Site Inspection

The LF-05 site was viewed on October 21, 2009. The inspection confirmed general site land use .assumptions for the site and also that construction activities were under way.

8.5.6 Interviews

No interviews were conducted with community members in regard to LF-05. A public notice was published in two area newspapers in December 2009, indicating that the review process was underway and providing contact information for questions or comments. No inquiries from the general public were received. Input on the review process was obtained from representatives of the USEPA, MDE, and Prince George's County through their participation in the Tier 1 partnering\ team and by their review of preliminary drafts of this document.

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8.6 LF-05 TECHNICAL ASSESSMENT • The remedy for LF-05 is currently under construction; therefore, its function could not be assessed. A LUCIP has notbeen drafted for LF-05. It is noted, however, that the BGP identifies LF-05 as an active, ERP site (PBS&J, 2009). Therefore, a Waiver-to-Construct is required for all proposed construction at the site (AFI 32-1021). A Waiver-to-Construct means the proposed construction has been evaluated with respect to site activity and environmental risks proposed by the construction and ultimate use of the facility.

In addition, groundwater is prohibited from being used for potable purposes anywhere on base (PBS&J, 2009) and COMAR 26.03.01.05 prohibits installation of new water supply wells.

Because of these conditions, major LUCs required by the ROD are already in place.

The exposure assumptions, toxicity data; cleanup levels, and RAOs for LF-05 were considered current at the signing of the ROD and have not been reviewed aspart of this review.

• No information has come to light during this review that could call into question the protectiveness of the remedy.

8.7 LF-05 ISSUES

No issues were identified.

8.8 LF-05 RECOMMENDATIONS AND FOLLOW-UP ACTIONS

There are no recommendations for follow-up other than to implementthe sdected remedy.

8.9 LF-05 PROTECTIVENESS STATEMENT

The selected remedy for LF-05 is expected to be protective of human health and the environment upon completion, and, in the interim, exposure pathways that could result in unacceptable risks are being controlled.

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8.10 LF-05 NEXT REVIEW LF-OS isastatutory 'site that requires ongomg five-year reviews. The next review will be • performed within five years of the completion of this five-year review report. The completion date is the date of the signature shown on the signature cover attached to the front of this report.

8.11 LF-05 REFERENCES

Booz Allen Hamilton, 2006. Groundwater Flow Model Report for LF-05 Leroy's Lane Landfill, Andrews AFB, MD. June.

CH2M Hill, 2004. Basewide Background Study, Andrews Air Force Base, Maryland. Prepared for Air Force Center for Environmental Excellence, March.

CH2M Hill, 2006. Site LF-05 Pre-Design Investigation Report, Andrews Air Force Base, Maryland. Prepared for Air Force Center for Environmental ExcelleI?-ce, September.

CH2M Hill, 2007. Technical Memorandum, Preliminary Ecological Evaluation for Leroy's Lane Landfill (LF-OS), Andrews Air ForceBase, Maryland, M~y.

Dames & Moore, Inc., 1992. Groundwater Contamination Survey, Andrews Air Force Base, Maryland.

Dames &Moore, Inc., 1994. HAZWRAP Technical Memorandum for LF-05, Andrews Air Force Base, Maryland. •• EA Engineering, Science and Technology, 1996. Draft Remedial Investigation Report, Leroy's Lane Landfill, Andrews Air Force Base, Maryland, prepared for U.S. Army Corps of Engineers, Baltimore and Omaha Districts, April.

Engineering Science, Inc. (ES), 1985. Phase I Records Search, Installation Restoration Program, Andrew:s AFB, Maryland, prepared for the U.S. Air Force, AFESC/DEV, and HQ MACIDEEV, June.

Earth Tech, 2006. Final Report for the Remedial Investigation for LF-05, Leroy's Lane Landfill, Andrews Air Force Base, Maryland. Prepared for Air Force Center for Environmental Excellence, December. .

Earth Tech, 2007. Final Feasibility Study for LF-OS, Leroy's Lane Landfill, Andrews Air Force Base, Maryland. Prepared for Air Force Center for Environmental Excellence, January ..

PBS&J, 2009. General Plan Update - Joint Base Andrews-Naval Air Facility Washington, '\ Maryland, December.

URS,2008a. Addendum to the Final Feasibility Study for LF-05, Leroy's Lane Landfill~ Andrews Air Force Base, Maryland. Prepared for Air Force Center for Engineering and the Environment, August. •

163

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URS, 2008b. Revised Ecological Evaluation of Sediment in the Vicinity of Landfill 05 (LF-05), Andrews Air Force Base, Maryland. Prepared for the Air Force Center for Engineering and • the Environment, August. URS, 2008c. Proposed Plan, Site LF-05, Leroy's Lane Landfill Remedial Action, Andrews Air Force Base, Maryland, August. .

USAF and USEPA, 2009. Record of Decision, LF-05 Leroy's Lane Landfill, Andrews Air Force Base, Maryland, July.

USEPA,2001. U.S. Environmental Protection Agency, 2001. "Comprehensive Five-Year Review Guidance"; EPA 540R-OI-007, June .

•

'.

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• Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

9.0 LF-06 FIVE-YEAR STATUS REVIEW • The LF-06, Landfill 6, Site is an ERP site that is in the CERCLA process at Joint Base Andrews. The ROD for LF-06 is in process and has not been signed, and ROD mandated remedial actions have not been identified or initiated. Therefore, this review is a status review that does not fully address all the review elements in USEPA's Comprehensive Five-Year Review Guidance (USEPA, 2001).

9.1 LF-06 DESCRIPTION AND CHRONOLOGY

LF-06 is located in the southern portion of the Base, between the south end of the west runway and South Perimeter Road (Figure 9.1f The headwaters of Piscataway Creek lie to the east ofLF-06. The Phase I Records search found that LF-06 (originally referred to as landfill site D-3) was an old gravel pit approximately 10 to 15 feet deep in the 1950s. The area was used for disposal of construction rubble from the late 1950s through the late 1960s. Minor quantities of"garbage, old paints, and equipment from the DRMO (Building 2326) were also reported to be buried at tQis location. In addition, unknown quantities of liquid waste (waste oils, paint thinners, and cleaning solvents) from industrial shOps were indiscriminately dumped at LF-06 (ES, 1985); A geophysical survey and intrusive investigations conducted as part of the RI found that the landfill activities • covered approximatdy 11 acres.

The area was gradually filled in to its present elevation.

A chronology of remedial studies, investigations, and reports at LF-06 is presented below.

.. 1985: Phase I Records Search (ES, 1985) • 1989 to 1990: IRP RIlFS (USGS, 1990) ". 1991 to 1992: Groundwater Contamination Survey (Dames & Moore, 1992b) • 1992: HAZRAP Technical Memorandum of Findings (Dames & Moore, 1992a) • 1992: Storm Water Management Study (Greenhorne & O'Mara, 1992) ". 1993: Phase I RIlFSLF-07ILF-07 (EA, 1992) • 1995: Phase II RIlFS Piscataway Creek (EA, 1995) ". 1997 to 2001: Long-term Groundwater Monitoring • 2004 to 2007: Remedial Investigation (Tetra Tech, 2007)

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9.2 LF-06BACKGROUND 9.2.1 Physical Characteristics • Most of LF-06 is a slightly rolling grassy field that gently slopes southeastward towards Piscataway Creek, with elevations ranging from about 220 feet above msl near Piscataway Creek to about 240 feet above msl in the northwestern/western portion of the site near Wisconsin Road, w~ere the former DRMO yard was located. Wetland areas are present adjacent to the surface water features at the site (Piscataway Creek on the eastern border of the site and along the upper tributary to Piscataway Creek present in the northern portion of LF-06). A small wetland is also present in the southern part of LF -06.

9.2;2 Land and Resource Use

LF-06 and the former DRMO are located entirely within an area designated for aircraft operations. The site is within the airfield/flight line security zone, and the site is fenced with a locking gate .. Access is restricted to authorized personnel, primarily lawn maintenance workers. No changes to land use are planned (PBS&J, 2009).

There are no potable water supply wells located at Joint Base Andrews, includiJ:lg LF-06, and there • is no current use or exposure to groundwater. Groundwater at LF-06is not expected to be used for such purposes in the future. Joint Base Andrews is currently served by public water supplied by the WSSC, and, according to COMAR 26.03.01.05, wells cannot be installed in areas where public water infrastructure is available.

No areas of archaeological or historical importance are present at LF-06.

9.2.3 History of Contamination

9.2.3.1 Surface Soil

The Rl reported detection of a number of SVOCs, pesticides, and PCBs ill surface soil. SVOCs are particularly widespread across the site at concentrations exceeding EPA Region III RBCs and/or SSLs. PCBs are present at concentrations exceeding RBCs/SSLs mainly in the western half of LF­ 06. Acetone was found at most locations sampled, but concentrations were well below the RBC and SSL. Only one location in the northern part of LF-06 revealed several other VOCs at trace 166 • P:IProjects\Andrews AFB EnvironmentallFive-year reviewsI4.0_ DeliverablesI4.I_ReportsIFinaIIAndrewsAFB_5- Yr Review_Revised March 201 l.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 20ll)

levels. Although arsenic concentrations are elevated in background surface soil at Joint Base Andrews relative to the RBC and SSL, it was found at concentrations exceeding background • mainly in the northwestern part of the site in the former DRMO area. Antimony and lead levels were also elevated in that area.

PCBs were found· in the sediments of Piscataway Creek adjacent to and downgradient of LF-06, and it appears that transport from LF-06 surface soils to the creek may have occurred. Some SVOC contamination found in Piscataway Creek sediments may be related to LF-06; however, it appears that runoff from the airfield is a significant source of SVOCs to Piscataway Creek (Tetra Tech, 2007).

,. , 9.2.3.2 Subsurface Soil

For the most part, elevated contaminant concentrations (i.e., greater than USEPA RBCs or SSLs) were detected in areas that were documented as containing fill material. The RI report concluded, based on the .soil boring logs, that the elevated concentrations were more likely because of the contaminated nature of the fill material than from downward migration of leachate from surface • soil (Tetra Tech, 2007).

Contaminants exceeding USEP A Region III Screening Levels included the pesticides aldrin and dieldrin; Arochlor-1260; Arochlor-1254; SVOCs, and metals. The concentration of antimony, arsenic, barium, cadmium, chromium, iron, manganese, mercury, selenium, silver, thallium, vanadium, and zinc equaled or exceeded their SSLs.

9.2.3.3 Groundwater

The generation and migration of leachate appears to have limited impact on LF -06 groundwater (Tetra' Tech, 2007). PCBs were .not detected in any groundwater sample. There were several detected SVOCs in groundwater, with just one MeL exceedance for benzo(a)pyrene. The one groundwater detection for pesticides also occurred at the same location, where dieldrin exceeded the tap RBC). VOC groundwater tap water RBC exceedances for l,4-dichlorobenzene and 1,2,4-trichlorobenzene occurred at one groundwater well. However, there were no primary MCL exceedances for metals. Dissolved iron and dissolved manganese were above EPA SMCL standards at most of the wells. The pH of the groundwater samples collected across LF -06 ranged

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Analytical data from LF-06 groundwater and Piscataway Creek indicate that groundwater from LF-06 is not impacting the creek surface water or sediment (Tetra Tech, 2007).

9.2.4 Iriitial Response

The RI identified approximately 2 feet of soil cover material at investigated areas. No other response actions have been taken at LF-06.

9.2.5 Risk Assessment Suinmary

The HHRA for the RI evaluated potential exposure risks for six receptor scenarios: other (site maintenance) workers - current and future, industrial. worker - future, construction worker ­ future, resident child - future, and resident adult - future.

Scenarios presenting cumulative risks equaling or exceeding the USEP A cancer risk management guideline oflxlO-4 and non-cancer HI threshold of 1 are listed in the following table.

LF-06 Exposure Scenarios Exceeding Risk Management Guidelines Rece tor Surface Soil Subsurface Soil Groundwater • Other Worker (current and future) CR< lE-04: Not evaluated HI < 1 Not evaluated Industrial Worker (current and future) Not evaluated CR < lE-04 Not evaluated m~11 Construction Worker (current and future) CR < lE-04 CR < lE-04 CR < IE-04 ~Jill HI = 1 Hi~f Child Resident (future) PR);Xg¥94 HI

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9.3 REMEDIAL ACTIONS

LF-06 is still in the CERCLA process leading to a ROD. A ROD has not been prepared or signed, • ( and no remedial actions have been performed at this site.

9.4 PROGRESS SINCE LAST FJVE-YEAR REVIEW

This status review is the fIrst inclusion 'of LF-06 in the fIve-year review process and precedes the signature of a ROD for LF-06.

9.5 LF-06 FIVE-YEAR STATUS REVIEW PROCESS

9.5.1 'Community Involvement

The USAF has maintained a public involvement arid information program for the ERP since 1990 and maintains an Administrative Record as required by CERCLA. The Administrative Record is maintained at .the Environmental Flight, 3466 North Carolina Avenue; Joint Base Andrews. For the convenience of the public, a copy of the Administrative Record is maintained in an Information • Repository located at: Prince George's County Memorial Library-Surratts-Clinton Branch 9400 Piscataway Road Clinton, MD 20735

Community involvement activities for this review consisted of publishing a notice in two local newspapers announcing the USAF's' intent to perform the fIve-year review and providing information where and how the public could obtain additional information. The notice appeared in

the Prince George's Coun~y Gazette on December 3, 2009, and in the Capital Flyer on December 18,2009. A copy of the notice is provided in Appendix A.

9.5.2 DocumentReview

The review included review of the following documents:

• Final Report for the Remedial Investigation at LF-06, LF-07, and Base Lake North Area (Tetra Tech, 2007) • General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland (PBS&J,2009) • 169 P:\Projects\Andrews AFB Environmental\Five-year reviews\4,0 _Deliverables\4, 1_Reports\Final\AndrewsAFB _5-Yr Review_Revised March 2011 ,doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting. Inc. Project Number 3350092494 (Revised March 2011)

9.5.3 Site Inspection The LF-06 site was viewed from outside the airfield/flight line security fence on October 21, 2009. • The inspection confmned general site conditions and site land use assumptions.

9.5.4 Interviews

No interviews were conducted with community members in regard to LF-06. Apublic notice was published in two area newspapers in December 2009, indicating that the review process was underway and providing conta~ct information for questions or comnlt~nts. No. inquiries from the general public were received. Input on the review process was obtained from representatives of the USEPA, MDE; and Prince George's County through their participation in the Tier 1 partnering team and by their review of preliminary drafts of this document.

9.6 LF-06 TECHNICAL ASSESSMENT

A remedy for LF -06 has not been selected or implemented; therefore, its function could not be assessed. It is noted, however, that the BGPOidentifies LF-06 as an active ERP site (PBS&J, 2009). Therefore, a Waiver-to-Construct is required for all proposed construction at the site (API 32­ 1021 )', A Waiver-to-Construct means the proposed construction has been evaluated with respect to • site activit~ and environmental risks proposed by the construction and ultimate use of the facility.

In addition, groundwater is prohibited from being used for potable purposes anywhere on Base (PBS&J, 2009) and COMAR 26.03.01.05 prohibits installation of new water supply wells. LF-06 is within the airfield security zone and access is limited to personnel with airfield/flight line security badges.

Because of these conditions, expected major LUCs of the ROD are already in place.

No information has come to light during this review to indicate that unacceptable short-term risks exist at the site.

9.7 LF-06 ISSUES

No issues were identified. 170 • P:\Prqjects\Andrews AFB EnvironmentallFive-year reviewsl4.0 _ DeliverablesI4.I_Reports\FinallAndrewsAFB_ 5-Yr Review_Revised March 2011.doc Join.! Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011) • 9.8 LF-06 RECOMMENDATIONS AND FOLLOW-UP ACTIONS There are no recommendations for short-term actions.

9.9 LF-06 PROTECTIVENESS 'STATEMENT

A remedial action has not been selected for LF-06; therefore, a protectiveness statement cannot be made.

9.10 LF-06 NEXT REVIEW

Because hazardous substances are expected to remain on site at levels exceeding those allowing unlimited use and unrestricted exposure, additional five-year reviews are anticipated. The next review will be performed within five years ofthe completion of this five-year review report. The completion date is the date of the signature shown on the signature cover attached to the front of this report.

9.11 LF-06 REFERENCES • Dames and Moore, Inc.,1992a. Technical Memorandum for the LF-07 Landfill, Andrews Air Force Base, Maryland. Prepared for the Hazardous Waste Remedial Action Program, Oak Ridge, Tennessee.

Dames and Moore, Inc., 1992b. Groundwater Contamination Survey, Andrews Air Force Base. Prepared for the Hazardous Waste Remedial Action Program, Oak Ridge, Tennessee.

EA Engineering, Science, and Technology, 1993. Assessment of Impacts of Landfills LF-06 and LF-07 on Piscataway. Creek and Surrounding Areas, U.S. Air Force, Armstrong Laboratories, San Antonio, Texas.

EA Engineering, Science, and Technology, 1995. Piscataway Creek, Remedial Investigation Phase II Reports, Volume I: Text, Andrews Air Force Base, Maryland.

ES (Engineering Science), 1985. Phase I: Record Search, Andrews Air Force Base, Maryland.

Greenhorne & O'Mara. 1992. Stormwater Management. Study~ Technical support for NPDES Stormwater Permit Application. Prepared for Andrews Air Force Base, Maryland.

PBS&J, 2009. G~neral Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland, December.

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Tetra Tech, Inc., 2007. Final Report for the Remedial Investigation at LF-06, LF-07, and Base Lake North Area, Andrews Air Force Base, Maryland, May. •

•

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10.0 LF-07IBLNAFIVE-YEAR STATUS REVIEW • The LF-07IBLNA, Landfill 7IBase Lake North Area, Site is an ERP site that is in the CERCLA process at Joint Base Andrews. The ROD for LF-07 IBLNA is in process and has not been signed, and ROD mandated remedial actions have not been identified or initiated. Therefore, this review is a status review that does not fully address all the review elements in USEPA's Comprehensive Five-Year Review Guidance (USEPA, 2001).

10.1 LF-07IBLNA DESCRIPTION AND CHRONOLOGY

LF-07 is located inthe southern portion of Joint Base Andrews, south of LF-06 and south of South Perimeter Road (Figure 10.1). Piscataway Creek lies to the east of LF-07, and Base Lake (also known .as Freedom Lake) is just southwest of LF-07. BLNA is located immediately northwest of Base Lake, between the lake and South Perimeter Road. The Phase I Records search found that LF-07 (originally referred to as landfill site D-4) was an old gravel pit used primarily for disposal of construction rubble from the 1960s through the 1980s. Some shop wastes -also may have been indiscriminately dumped at LF-07. Asre~'ently .as 1984, the following items were found at this landfill: old furniture, washing machines, metal lockers, sheet and scrap metal, household garbage, plastics, empty 55-gallon drums, waste lumber, tires, pipes, and hospital wastes including unused • needles and chemical reagents (Engineering SCience, 1985). Based on field activities conducted during the RI, fill or pockets of fill are widespread across the Site. Fill material generally consisted of varying amounts of wood, concrete, brick, ash, metal, and rubber mixed with a soil matrix. Investigations conducted as part of the RI indicate that the landfill activities covered approximately 28 acres (Tetra Tech, 2007).

BLNA(originally referred to as the D-2 landfill) is reported to have been active during the initial construction of Joint Base Andrews from 1942 to 1955. This area was used for the disposal of general refuse and construction rubble. No liquid or hazardous wastes are known to have been . buried at this location. Trenches were reported to have been excavated 10 to 12 feet deep and 15 feet wide within the area. Construction rubble and general refuse were buried in these trenches and covered daily with local soil (Engineering Science, 1985). Investigations conducted as part of the RI indicate that the landfill activities covered approximately 20 acres (Tetra Tech, 2007).

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The area was gradually filled in to its present elevation.

A chronology of remedial studies, investigations, and reports atLF-07IBLNA is presented below. •

.• 1985: Phase I Records Search (ES, 1985) .1989 to 1990: IRP RIlFS (USGS, 1990) .1991 to 1992: Groundwater Contamination Survey (Dames & Moore, 1992b) • 1992: HAZRAP Technical Memorandum of Findings (Dames & Moore, 1992a) • 1992: Storm Water Management Study (Greenhorne & O'Mara, 1992) • 1993: Phase I RIlFS LF-07ILF-07 (EA, 1992) • 1995: Phase II RVFS Piscataway Creek(EA, 1995) • 1997 to 2001: Long-term Groundwater Monitoring • 2004 to 2007: Remedial Investigation (Tetra Tech, 2007)'

10.2 LF-07IBLNA BACKGROUND

10.2.1 Physical Characteristics

LF-07 comprises. the manicured parts of several holes of the South Course at Joint Base Andrews, areas of tall unmanicured grass,and pockets of wooded areas. Overall topography is gently rolling • and the land surface gently slopes towards Piscataway Creek to the east. Elevations at LF ~07 range' from about 220 feet above msl at the eastern edge of the site near Piscataway Creek to about242 feet above msl in the western part of the site. A small wetland "is present in the southern part of the site that drains via buried pipe to Berry Pond, located on Joint Base Andrews property, but outside the fence that establishes the secure boundary of the Base.

Similar to LF-07, BLNA comprises several golf course holes (both the South and East Courses at Joint Base Andrews) with the remaining land surface primarily tall unmanicured grass with some pockets of wooded areas. A marsh/wetland area is present in the central part· of BLNA. The central part of BLNA is the highest topographically at an elevation of about 260 feet above ms!. The land surface slopes away from the center of the site towards Base Lake to the southeast, South Perimeter Road to the north, and additional golf course areas to the west. Land surface elevation at the northwestern edge of Base Lake is about 240 feet above msl.

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10.2.2 Land and Resource Use • LF-07 and BLNA. are located within an unrestricted area of Joint Base Andrews, and both sites contain portions of the Base golf courses. In addition, there is a picnic area on the westemedge on Base Lake. These sites are expected to remain in recreational land use for the foreseeable future (PBS&J, 2009).

There are no potable water supply wells located at Joint Base Andrews, including LF-07IBLNA, and there is no current potable use of, or exposure to, groundwater. Groundwater at LF-07IBLNA is not expected to be used for potable purposes in the future. Joint Base Andrews is currently served by public water supplied by the WSSC, and, according to COMAR 26.03.01.05, wells cannot be installed in areas where public water infrastructure is available.

No areas of archaeological or historical importance are presentat LF-07IBLNA.

The only federally listed endangered animal species that may occur in the vicinity of LF-07 IBLNA is the Bald Eagle, which has been observed near Base Lake. No nests are present on the Base and • this species is thought to be transient to the Base. No additional state or federally listed threatened or endangered animal species have been identified at Joint Base Andrews (USAF.2001).

Several plant species of concern may be present in the LF-07IBLNA area. From the previous rare species inventories, it is known that one federally listed endangered plant species, sandplain gerardia (Agalinis acuta), has occurred at the Base in the vicinity of LF-07, although subsequent surveys of the area have not been able to locate this species. However, the presenc.e of purple gerardia, a common associate of sandplain gerardia, indicates that suitable habitat may still exist (USAF 2001). The state-listed endangered species ten-lobed agalinis may occur along Piscataway Creek near the Base boundary. Spiral pondweed (highly state rare) and tall nut-rush (state rare) may be present south of LF-07 near the southern Base boundary (USAF 2001). These areas, however, are out of the LF-07IBLNAarea.

Wetlands are located in and around LF-07IBLNA and are associated primarily with Base Lake, Piscataway Creek, and the golf course. The wetlands present at LF-07IBLNA are either palustrine forested wetlands associated 'with Piscataway Creek or its tributaries, or wetlands that have formed ••• as a result of anthropogenic activities (i.e., disturbed or manmade features associated with 175

P:IProjectslAndrews AFB EnvironmentallFive-year reviewsl4.0_ DeliverablesI4.1_Reports\FinallAndrewsAFB_5- Yr Review_Revised March 201l.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011) landfilling/rubble-filling, grading, etc.) (EA 1995). No areas of archaeological or historical importance have been identified at LF07IBLNA. .­ 10.2.3 History of Contamination

10.2.3.1 LF-07 Surface Soil

A number of SVOCs were detected in surface soil at locations scattered across the LF-07. Almost one-third of the locations sampled exceeded at least one SVOC RBC, and these locations were primarily in the western-half of LF-07. Pesticides and PCBs were detected less frequently than SVOCs. The pesticide dieldrin, exceeded the residential RBC at five locations, and PCBs were detected at concentrations below RBCs. VOCs were not widespread and all detects were below SSLs and RBCs. A number of metals were detected in surface soils above SSLs, but arsenic was the only metal to exceed its RBC (Tetra Tech, 2007).

10.2.3.2 LF-07 Subsurface Soil

Elevated contaminant concentrations were generally detected in LF-07 areas that were documented as containing fill material. Based on the soil boring logs, the elevated concentrations were more likely because of the contaminated nature of the fill material than from downward migration of • leachate from surface soil. The highest total pesticides concentrations in subsurface' were found in or adjacent to areas containing source fIll. Eleven of 30 locations exceeded the SSL for dieldrin. Gamma-chlordane exceeded the SSL at two locations. Pesticides were not detected in soil greater than nine feet bgs. The maximum total PCB concentrations in subsurface soil occurred at locations containing source fill, although no detects exceeded the EPA industrial RBC. PCBs were not detected in soil greater than 9 feet bgs (Tetra Tech, 2007).

At LF-07, the maximum total SVOC concentrations occurred at in areas containing source fill. RBC/SSL exceedancesoccurred at 11 of 30 locations. SVOCs were not detected greater than 14 feet bgs. No samples had a VOC concentration above a SSL. A range of metals was detected in samples 'in all sampling locations. Concentrations of antimony, arsenic, barium, cadmium, chromium, manganese, mercury, selenium, silver, and vanadium equaled or exceeded SSLs. Arsenic exceeded its industrial and residential RBCs, and iron and one lead sample exceeded the residential RBC (Tetra Tech, 2007).

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10.2.3.3 LF-07 Groundwater • The impact to LF-07 groundwater from leachate migration appears to be limited. PCBs were not detected in any.groundwater sample. There were several detected SVOCsin groundwater, with just one exceedance of the EPA RBC for bis(2-ethylhexyl)phthalate and one exceedance of the MCL (0.20 flglL) for benzo(a)pyrene). Pesticides (heptachlor epoxide and gamma-chlordane) were detected in one groundwater well, and the concentration for heptachlor epoxide (0.47 flglL) exceeded the McL (0.20 flglL). These pesticides are likely from leachate as groundwater well LF07-MW18 is screened below subsurface soil containing pesticides (Tetra Tech, 2007).

There were no groundwater MCL exceedances for VOCs.

Dissolved metal concentrations in groundwater may be elevated' because of landfill leachate; however, the MCL exceedances occurred in only two sampled wells: dissolved cadmium in LF07- MW14and dissolved arsenic in LF07-MW20. Dissolved iron and dissolved manganese were greater than SMCLs at most of the wells. The pH of the groundwater samples collected across LF­ 07 ranged from 4.17 to 6.73. Groundwater with pH in the lower part of this range could be acidic • enough to cause some leaching of metals (Tetra Tech, 2007).

10.2.3.4 BLNA Surface Soil

SVOCs and PCBs were detected in surface soil at almost all sampling locations. RBCs and SSLs . were exceeded at many locations for these compounds. Other than low levels of acetone, VOCs were not widely detected in BLNA surface soils. Arsenic was the only metal to exceed residential and industrial RBCs.

10.2.3;5 BLNA Subsurface Soil

Elevated contaminant concentrations were generally detected in areas that were documented as containing fill material. Based on soil boring log descriptions, the elevated concentrations were more likely because of the contaminated nature of the fill material than from downward migration of leachate from surface soil (Tetra Tech, 2007).

The pesticides aldrin and dieldrin exceeded EPA RBCs/SSLs at one location, and dieldrin exceeded theSSL at two locations. Pesticides were not detected in soil below 10 feet. Aroc1or­ • 177 P:\ProjectslAndrews AFB Environmental\Five-year reviews\4.0 _ Deliverables\4.I_Reports\FinallAndrewsAFB_5- Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

1242 exceeded the USEPA industrial soil RBC at a depth of 10 feet at a location in a source-fill area. • Samples from nine of the eighteen boring locations contained exceedances of USEPA RBCs/SSLs for SVOCs. SVOC concentrations were greatest in a sample from a source-fill area.

The maximum total VOC concentrations occurred in a 10-foot-bgs sample from a source-fill.area, ( where exceedances' for l,4-dichlorobenzene, chlorobenzene, and total xylenes were recorded. This location also contained the highest total concentrations for PCBs.

A range of metals was detected in samples from all borings. Concentrations of antimony, arsenic, cadmium, chromium, iron, manganese, mercury, selenium, and silver equaled or exceeded SSLs. Arsenic and iron exceeded the industrial and residential RBCs, respectively. The highest concentrations of pesticides, PCBs, and SVOCs occurred within areas documented as source-fill.

10.2.3.6 BLNA Groundwater

Although surface and subsurface soil contamination is present at BLNA, the overall impact to groundwater does not appear to be widespread (Tetra Tech, 2007). There were several·detected SVOCs in groundwater, with one exceedance of the RBC for bis(2-ethylhexyl)phthalate in • groundwater sample BLNA-MWOl, and exceedances of the RBCs for indeno[1,2,3-c,d]pyrene, and . . . dibenzo[a,h]anthracene in the sample from BLNA-MW02. Pesticides and PCBs were not detected in any of the BLNA groundwater samples. The VOC 1,4-dichlorobenzene was detected most often in groundwater and exceeded its tap water RBC (0.47 )lg/L) in three wells, but was well below its MCL of 75 )lg/L in all samples. Total chromium exceeded its MCL (140 vs. 100)lg/L) in one well.

Dissolved metal concentrations in groundwater may be elevated because of landfill leachate (Tetra Tech, 2007). However, dissolved iron and dissolved manganese were the only metals above EPA SMCLs, and these naturally occurring elements were also found at elevated concentrations at LF­ 06 and LF-07. The pH of the groundwater samples collected across BLNA ranged from 4.83 to 6.77. Groundwater with pH in the lower part of this range could be acidic enough to cause some leaching of metals (Tetra Tech, 2007).

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10.2.4 Initial Response • The RI identified approximately 2 feet of soil cover material at investigated areas. No other response actions have been taken at LF-07IBLNA.

10.2.5 Risk Assessment Summary

10.2.5.1 LF-07 Risk Assessment Summary

The HHRA for the RI evaluated potential exposure risks for the following receptor scenarios: other (site maintenance) workers- current and future, industrial worker - future, construction worker ­ future, resident child - future, resident adult - future, preadolescent golfer - current and future.

Scenarios presenting cumulative risks equaling or exceeding the USEPA cancer risk management guideline of 1x 10"" and non-cancer HI threshold of 1 are listed in the following table.

LF-07 Exposure Scenarios ·Exceeding Risk Management Guidelines Rece tor Surface Soil Subsurface Soil Groundwater Other Workers (current and future) CR < lE-04 CR < lE-04: Not evaluated HI < 1 HI < 1 Not evaluated Industrial Workers (current and future) ~ • CR < IE-04 Not evaluated . CR < lE-04 HI < 1 Not evaluated HI < 1 Construction Worker (current and future) CR < lE-04 CR < IE-04: CR

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10.2.5.2 BLNA Risk Assessment Summary The HHRA for the RI evaluated potential exposure risks for the following receptor scenarios: other • (site maintenance) workers- current and future, industrial worker - future, construction worker ­ future, resident child - future, resident adult - future, preadolescent golfer - current and future.

~cenarios presenting cumulative risks equaling or exceeding the USEP A cancer risk management guideline of Ix I0-4 and non-cancer HI threshold of 1 are listed below.

BLNA Exposure Scenarios Exceeding Risk Management Guidelines Rece tor Surface Soil Subsurface Soil Groundwater

Shade indicates exceedance of risk-management guideline. Potential CR to adult resident from exposure to air and sediment less than I E-04.

10.3 REMEDIAL ACTIONS

LF-07IBLNA is still in the CERCLA process leading to a ROD. A ROD has not been prepared or signed, and no remedial actions have been performed at this site.

10.4 PROGRESS SINCE LAST FIVE-YEAR REVIEW

This status reVIew is the fIrst inclusion of LF-07IBLNA in the fIve-year review process and precedes the signature ofa ROD for LF-07IBLNA.

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10.5 LF-07IBLNA FIVE-YEAR STATUS REVIEW PROCESS • 10.5.1 Community Involvement The USAF has maintained a public involvement and information program for the ERP since 1990 and maintains an Administrative Record as required by CERCLA. The Administrative Record is maintained at the Environmental Flight, 3466 North Carolina Avenue, Joint Base Andrews. For the convenience of the public, a copy bfthe Administrative Record is maintained in an Information Repository .located at:

Prince George's County Memorial Library-Surratts-Clinton Branch 9400 Piscataway Road Clinton, MD20735

Community involvement activities for this review consisted of publishing a notice in two local newspapers announcing the USAF's intent to ·perform the five-year review and providing information where and how the public could obtain additional information. The notice appeared in the Prince George's County Gazette on December 3, 2009, and in the Capital Flyer on December 18,2009. A copy of the notice is provided in Appendix A.

• 10.5.2 Document Review

The review included review of the following documents:

'. Final Report for the Remedial Investigation at LF-06, LF-07, and Base Lake North Area (Tetra Tech, 2007) • General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland (PBS&J,2009)

10.5.3 Site Inspection

The LF-07IBLNA sites were viewed on October 21, 2009. The inspection confirmed general site conditions and land use assumptions.

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10.5.4 Interviews No interviews were conducted with community members in regard to LF-07IBLNA. A public • notice was published in two area newspapers in December 2009, indicating that the review process was underway and providing contact information for questions or comments. No inquiries from the general public were received. Input on the review process was obtained from representatives of the USEP A, MDE, and Prince George's County through their participation in the Tier 1 partnering . team and by their review of preliminary mafts of this document.

10.6 LF-07IBLNA TECHNICAL ASSESSMENT

A remedy for LF-07IBLNA has no~ been selected or implemented; therefore, its function could not be assessed. It is noted, however, that the BGP identifies LF-07 as an active ERP site (PBS&J, 2009). Therefore, a Waiver-to-Construct is required for all proposed construction at the site (API 32-1021). A Waiver-to-Construct means the proposed construction has been evaluated with respect to site activity and environmental risks proposed by the construction and ultimate use of the facility.

In addition, groundwater is prohibited from being used for potable purposes .anywhere on Base (PBS&J, 2009) and COMAR 26.03.01.05 prohibits installation of new water supply wells. •

Because of these conditions, expected major LUCs of the ROD are already in place.

No information has come to light during this review to indicate that unacceptable short-term risks exist at the site.

10.7 LF..;07IBLNA ISSUES

No issues were identified.

10.8 LF-07IBLNA RECOMMENDATIONS AND FOLLOW-UP ACTIONS

There are no recommendations for short-term actions

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10.9 LF-07IBLNA PROTECTIVENESS STATEMENT • A remedial action has not been selected for LF-07IBLNA; therefore, a protectiveness statement cannot be made.

10.10 LF-07IBLNA NEXT REVIEW

Additional five-year reviews are anticipated. The next review will be performed within five years of the completion of this five-year review report. The completion date is the date of the signature shown on the signature cover attached to the front of this report.

10.11 LF-'07IBLNA REFERENCES

Dames and Moore, Inc., 1992a. Technical Memorandum for the LF-07 Landfill, Andrews Air Force Base, Maryland. Prepared for" the Hazardous Waste Remedial Action Program, Oak Ridge, Tennessee.

Dames and Moore, Inc., 1992b. Groundwater Contamination Survey, Andrews Air Force Base. Prepared for the Hazardous Waste RemedialAction Program, Oak Ridge, Tennessee.

EA Engineering, Science, and Technology, 1993. Assessment of Impacts of Landfills LF-06 and LF-07 on Piscataway Creek and Surrounding Areas, U.S. Air Force, Armstrong • Laboratories, San Antonio, Texas. EA Engineering, Science, and Technology, 1995. Piscataway Creek, Remedial Investigation Phase II Reports, Volume I: Text, Andrews Air Force Base, Maryland .

. ES (Engineering Science), 1985. Phase I: Record Search, Andrews Air Force Base, Maryland.

Greerihome & o'Mara, 1992. Stormwater Management Study. Technical support for NPDES Stormwater Permit Application. Prepared for Andrews Air Force Base, Maryland.

PBS&J, 2009. General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland, December.

Tetra Tech, Inc., 2007. Final Report for the Remedial Investigation at LF-06, LF-07, and Base Lake North Area, Andrews Air Force Base, Maryland, May.

183 • . . f P:IProjec\S\Andrews AFB EnvlronmentallFive-year reviewsl4.0 _DeliverablesI4.I_ReportslFinal\Andre·wsAFB_5- Yr Review_Revised March 2011.doc 1 1 1 1 1 1 1 1 1 1 1 1 (This page intentionally left blank) 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 • 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 • 1 Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

11.0 SS-26 FJVE-YEAR STATUS REVIEW • The SS-26, Hangar 15, Site (formerly AOC 30) is an ERP site that is in the CERCLA process at Joint Base Andrews. The ROD for SS-26 has not been developed, and ROD mandated remedial actions have not been identified or initiated. Therefore, this review is a status review that does not r fully address all the review elements in USEPA's Comprehensive Five-Year Review Guidance (USEPA,2001).

11.1 SS-26 DESCRIPTION AND CHRONOLOGY

SS-26 is located on the west side of East 'Perimeter Road adjacent to the east operational apron (Figure 11.1). Hangar 15 was constructed in 1947 and demolished in 1998 and was used for aircraft and equipment maintenance. Two small adjacent buildings (784 and 785), located southeast of the hanger, were constructed in 1986 and used for storage. The site encompasses approximately 4.22 acres (HGL, 2007).

Former tenants of the hangar included the ANG in the early 1980s,the 89th Transportation, Civil Engineering Grounds; Civil Engineering Snow Equipment, and the Aero Club. In the 1980s, the hangar usage changed from maintaining and storing various .types of aircraft to maintenance of • aircraft, vehicles, and ground equipment. It was used by Civil Engineering to house snow plows at the time ofdemolition in 1998.

Activities at the hangar are known to have generated petroleum and hazardous waste. Oil and solvent spills were evident by stains on the hangar floor and apron' during the preliminary assessment (HGL, 2007). Areas identified as potential contaminant sources include the hangar drains, interior and exterior waste accumulation areas, an oil/water separator, two 1,000-gallonfuel oil USTs, one 1,000-gallon waste oil AST, the storage buildings, miscellaneous spills on the' concrete apron, and potentially the former hangar's hydrant fuel system. Currently the site is occupied by the District of Columbia ANG 113th Civil Engineer Squadron. A washrack is located to the south of the site that is currently being used (HGL, 2007).

A chronology of remedial studies, investigations, and reports at SS-26 is presented below.

• 1995: Preliminary Assessment/Site Investigation • 1996: Phase I Environmental Baseline Survey • 184 P:IProjectslAndrews AFB Environmental\Five-year reviewsl4.0 _DeliverablesI4.1_ ReportslFinallAndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting. Inc. Project Number 3350092494 (Revised March 2011)

• 1997: Phase II Environmental Survey (IT, 1997) • 2006 to 2007: Preliminary Assessment/Site fuvestigation (HGL, 2007) • 11.2 SS-26 BACKGROUND

11.2.1 Physical Characteristics

SS-26 is relatively flat, with the majority of the site covered by concrete, ranging in elevation from approximately 270.5 to 275 feet above msl. There is a grassy area, approximately 0.9 acre, to the north of the site in the area of former Hangar 15.. There are no surface water features at the site. The surface water run-off at the site is collected via storm sewers located at the site (HGL, 2007).

11.2.2 Land and Resource Use

The SS-26 site is currently occupied. by the District of Columbia ANG 113th Civil Engineer Squadron and is designated for aircraft operations and maintenance,both currently and in the future. A washrack that is currently being used is located to the south of the site. The site is located within the Joint Base Andrews airfield/flight line security zone, .and only authorized individuals can enter. • According to the Hangar 15 Fact Sheet, the Navy has construction plans for the site (316th CES, 2009).

There are no potable water supply wells located at Joint Base Andrews, including SS-26, and there is no current use or exposure to groundwater. Groundwater at SS-26 is not expected to be used for such purposes in the future. Joint Base Andrews is currently served by public. water supplied by the WSSC, and, according to COMAR 26;03.01;05, wells cannot be installed in areas where public water infrastructure is available.

No areas of archaeological or historical importance have been identified at SS-26.

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11.2.3 History of Contamination • 11.2.3.1 Soil During the Preliminary Assessment / Site Investigation (P AlSI), 14 direct push soil borings were completed at the site with continuous collection of subsurface soil samples. All soil samples were screened with a PID and visually examined for indications of staining. Samples from five locations which had elevated PID readings or visual evidence of staining were analyzed for VOCs by a mobile laboratory. Three of the soil samples were sent to a fixed laboratory for analysis for VOCs, SVOCs, metals, PCBs, TPH-GRO and TPH-DRO. Soil samples submitted for fixed laboratory analysis were selected on the basis of PID readings and mobile laboratory results.

The Supplemental SI Work Plan (URS, 2008) compared results from the mobile laboratory to risk­ based screening levels (RBSLs) recommended for use by USEPA Region 3. None of these samples exhibited VOCs detected at concentrations greater than the residential RBSL calculated for a target cancer risk of Ix10-6 and/or a non-cancer target HQ of 0.1. Consequently, no analytes from the vadose zone samples would have been retained for quantitative analysis in a risk

assessment. Two samples each had one chemical at a concentration which exceeded risk~based protection of groundwater screening levels. None of these chemicals were at concentrations which • exceeded available MCL-based protection of groundwater screening levels (URS, 2008).

All three of the locations from which subsurface samples were submitted to the fixed laboratory were from the vadose zone. The Supplemental SI Work Plan -CURS, 2008) compared the analytical results to RBSLs recommended for use by USEPA Region 3. None of these samples exhibited chemicals detected at concentrations greater than their residential RBSLs. Vinyl chloride was detected in one sample at a concentration which exceeded the RBSL for protection of groundwater. This concentration was less than the MCL-based protection of groundwater screening level. A second sample had concentratioIis of arsenic (Ll mg/kg) and iron (5,740 mg/kg) that exceeded their respective residential RBSLs. However, the Supplemental SI Work Plan identified both of these concentrations as less than the background UTL concentrations for these metals established during' the Andrews APB Basewide Background Study (CH2MHill, 2004). The UTL concentrations for arsenic and iron developed during the Basewide Background Study were 6.2 mg/kg and 27,800 mg/kg, respectively. Consequently, no chemicals detected in vadose zone samples would have been retained for quantitative analysis in a risk assessment. In addition, no

• 186 P:\Projects\Andrews AFB EnvironmentallFive-year reviewsI4.0_DeliverablesI4.1_ ReportslFinal\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011) site-related chemicals were detected at concentrations which exceeded their MCL-based SSLs (URS, 2008). • 11.2.3.3. Groundwater

Data collected during the P NSI show the chlorinated VOCs TCE and its reductive dehalogenation products cis-l,2-DCE and vinyl chloride distributed throughout the site at concentrations greater than MCLs. The PNSI concluded a release of TCE may have occurred west of or beneath Building 3121 and recommended additional investigation.

11.2.4 Risk Assessment Summary

A risk assessment has not been completed for SS-26. The data from the PA/SI suggest, however, that soil does not present a significant risk. Groundwater concentrations of TCE, cis-l ,2~DCE, and vinyl chloride exceeded MCLs.

11.3 SS-26 REVIEW PROCESS

11.3.1 Community Involvement

The USAF has maintained a public involvement and information program for the ERP since 1990 • and maintains an Administrative Record as required by CERCLA. The Administrative Record is maintained at the Environmental Flight, 3466 North Carolina A venue, Joint Base Andrews. For the convenience of the public, a copy of the Administrative Record is maintained in an Information Repository located at:

Prince George's' County Memorial Library-Surratts-Clinton Branch 9400 Piscataway Road Clinton, MD20735

Community involvement activities for this five-year review consisted of publishing a notice in two local newspapers announcing the USAF's intent to perform the five-year review and providing information where and how the public could obtain additional information. The notice appeared in the Prince George's County Gazette on December 3, 2009, and in the Capital Flyer on December 18, 2009. A copy of the notice is provided in Appendix A.

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11.3.2 Document Review • This review included review ofthe' following documents:

• Final Preliminary Assessment/Site Investigation Report, Site SS-26 (HGL, 2007) • Draft Supplemental Investigation Work Plan for Site SS-26 (DRS, 2008) • General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland (PBS&J, 2009)

11.3.3 Site Inspection

The SS-26 site was viewed from outside the airfield/flight line security fence on October 21, 2009. The inspection confirmed general site conditions and site land use assumptions.

11.3.4 Interviews

No interviews were conducted with community members in regard to SS-26. A public notice was published in two area newspapers in December 2009, indicating that the review process was • underway and providing contact information for questions or comments. No inquiries from the general public were received. Input on the review process was obtained from representatives ofthe USEPA, MDE, and Prince George's County through their participation in the Tier 1 partnering team and by their review of preliminary drafts of this document.

11.4 SS-26 TECHNICAL ASSESSMENT

The data from the P AlSI suggest that soil does not present a significant risk; however, groundwater concentrations·of TCE, cis-I,2-DCE, and vinyl chloride exceeded MCLs. Therefore, preventing

exposure to soil is ~nlikely to be a RAO, although prevention of potable use groundwater would be aRAO.

It should be noted, however, that the BGP identifies SS-26 as an active ERP site (PBS&J, 2009). Therefore, a Waiver-to-Construct is required for all proposed construction at the site (API 32­ 1021). A Waiver-to-Construct means the proposed construction has been evaluated with respect to site activity and environmental risks proposed by the construction and ultimate use of the facility.

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In addition, groundwater is prohibited from being used for potable purposes anywhere on Base

(PBS&J, ~009) and COMAR 26.03.01.05 prohibits installation of new water supply wells. S-26 is within the airfield security zone and access is limited to personnel with airfield/flight line security • badges.

11.5 SS-26 ISSUES

No issues were identified.

11.6 SS-26 RECOMMENDATIONS AND FOLLOW-UP ACTIONS

There are no recommendations for short-term actions.

11.7 SS-26 PROTECTIVENESS STATEMENT

A remedial action has not been selected' for SS-26; therefore, a protectiveness statement cannot be made. 11.8 SS-26 NEXT REVIEW • Additional five-year reviews are anticipated. The next review will be performed within five years of the completion of this five-year review report. The completion date is the date of the signature shown on the signature cover attached to the front of this report

11.9 SS-26 REFERENCES

HGL (HydroGeologic, Inc.), 2007. Final Preliminary Assessment/Site Investigation Report, Site SS-26, Andrews AFB, Maryland, December.

IT Corporation, 1997. Draft Phase II Environmental Baseline Survey at Hangar 15 (Building 3129), Andrews Air Force Base, Maryland, December.

IT Corporation, 2000. Installation-Wide Sampling and Analysis Plan, Andrews Air Force Base, Maryland, August

PBS&J, 2009. General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland, December.

Tetra Tech, Inc., 1995. Final IRP, RCRA Facility Investigation/Correction Measures Study • Technical Report, Andrews AFB, Maryland.

189

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DRS,2008. Draft Supplemental Investigation Work Plan for Site SS-26, Andrews Air Force Base, • . Maryland, December.

•

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12.0 SS-27 FIVE-YEAR STATUS REVIEW • The SS-27, Former Dry Cleaner Building 1623, Site is an ERP site that is in the CERCLA process at Joint Base Andrews. SS-27 was formerly designated AOC 31. The ROD for SS-27 had not been completed at the time the five-year review was conducted (although a ROD was subsequently signed in February 2011); therefore, this review is a status review that does not fully address all the review elements in USEPA's Comprehensive Five-Year Review Guidance (USEPA, 2001).

12.1 SS-27 DESCRIPTION AND CHRONOLOGY

SS-27 is located on the west side of the airfield at the corner of Arnold A venue and Arkansas Road in a developed area of the Base (Figure 12.1) .. Building 1623 was formerly an Army and Air Force Exchange Service dry-cleaning facility. The facility was operated on site for approximately 12 to 15 years from the 1980s to 1996. The facility used a 35-pound capacity dry cleaning machine that used 3 gallons of PCE per load. The machine operated about 12 times per day, 6 days per week. Building 1623 was demolished in 1996 when dry-cleaning operations ceased (DRS, 2009b).

A chronology of remedial studies, investigations, and reports at SS-27 is presented below.

• • 2004: Preliminary Assessment/Site Investigation (EEG, 2005) • 2006 t02007: CERCLA Phase I Remedial Investigation (Tetra Tech, 2007) • 2008: CERCLA Phase II Remedial Investigation (URS, 2009) • 2009: Draft Feasibility Study (URS, 2009)

12.2 SS-27 BACKGROUND

.12.2.1 Physical Characteristics

The ground surface at SS-27 is relatively level, generally sloping towards the south to ~outheast and ranging in elevation from approximately 278 feet above msl in the central portion of the site to approximately 275 feet above msl immediately north of Arkansas Road. South of Arkansas Road, the study area elevation is approximately 275 feet above ms!. East of Arnold Avenue, the ground surface elevation is approximately 272 feet above msl (URS, 2009b).

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12.2.2 Land and Resource Use The SS-27 site is currently vacant, consisting of grassed lawn and paved parking areas. Existing • land use for the generai area includes aircraft operations and mamtenanceand administrative activities. Future land use is designated as administrative (PBS&J, 2009). The administrative land use category includes military and civilian personnel offices, family services and support centers, security forces operations, wing and group headquarters, and communications centers;

There are no potable water supply wells located at Joint Base Andrews, including SS-27, and there is no current use or exposure to groundwater. Groundwater at SS-27 is not expected to be used for such purposes in the future. Joint Base Andrews is currently served by public water supplied by the WSSC, and, according to COMAR 26.03;01.05, wells cannot be installed in areas where public water infrastructure is available.

No areas of archaeological or historical importance have been identified at SS-27.

12.2.3 History of Contamination Results of the RI sampling at SS-27 indicate the presence of PCE and TCE contamination in soil -. and PCE, TCE, cis-1,2-DCE, vinyl chloride, and chlorofonn in groundwater. Other COPCs in groundwater at SS~27include aldrin, dieldrin, and manganese. No PCBs were detected in any of the monitoring well samples.

VOCs detected above their respective drinking water MCLs and/or tap water RBCs included

1,1-DCE, trans-1,2-DCE, cis~1,2-DCE, bromo methane, tert-butyl methyl ether, benzene, l,4-dichlorobenzene, PCE, TCE, and vinyl chloride. Although methyl ethyl ketone and toluene were detected ill several groundwater samples, their presence was attributed to blank contamination. VOCsexceeded MCLs and RBCs in samples collected from four wells.

Although PCE and its associated degradation products TCE and cis-1,2-DCE were detected in many of the Phase I RI surface soil samples, contamination in surface soils is limited and appears to be confmed to the western edge of the fonner building footprint. PCE was detected in 12 of the 19 (63 percent) surface soil sampling locations at concentrations from 1.5 to 6,800 Ilgikg. TCE was detected in 4 of the 19 surface soil sampling locations at concentrations from 1.4 to 59 Ilgikg . Cis-1,2-DCE was detected in 3 of the 19 surface soil sampling locations at concentrations from 1.9 192 • P:IProjects\Andrews AFB EnvironmentallFive-year reviewsl4.0 _ DeliverablesI4.1_ReportslFinal\AndrewsAFB _ 5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

to 16 Ilgikg. All TCE and Cis-l ,2-DCE detections were below Region III residential RBCs. Only • one sample (SSI8) exceeded residential and industrial RBCs for PCE. No Phase II RI subsurface soil samples exceeded their respective residential and/qr industrial RBC screening criteria or site-specific SSLs.

The source of the solvent contarriination at SS-27 appears to be a spill/release of dry cleaner solvents to the ground surface. Surface and subsurface soil along the western edge of the building footprint and groundwater within and downgradierit of the footprint contain elevated concentrations ofPCE and associated breakdown products TCEand cis-l,2-DCE (Tetra Tech, 2007).

12.2.4 Risk Assessment Summary

A streamlined HHRA was conducted for groundwater and soil to identify COCs to be addressed in the FS, instead of a more comprehensive HHRA to determine if further action is warranted (URS, 2009a). . The streamlined HHRA identified PCE, vinyl chloride, TCE, and chloroform as groundwater COCs. The only soil COC identified by the streamlined HHRA is PCE. It is a coe • in shallow subsurface soil (2 to 10 feet bgs) only. Risks from exposure to surface soil (0 to 2 feet bgs) were within the USEP A risk management range for both industrial workers and future residents.

Based on the results of the streamlined HHRA, the shallow groundwater at SS-27 poses an unacceptable Tisk to human health over a limited area, if the groundwater were used as a drinking I water source in the future. In addition, PCE in the shallow subsurface soil poses an unacceptable risk to human health if workers or residents are present at the site and exposed to PCE in soil via incidental ingestion and inhalation over an extended period of time (the assumed exposure duration used to derive the soil RSL is 25 years for an industrial worker and 30 years for a resident). Because future plans for the site involve construction of an administrative office building, vapor intrusion from groundwater and soil to indoor environments is also an exposure pathway of concern. Additional discussion regarding the HHRA is presented in the Phase TIRI Report (URS, 2009a).

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12.3 SS-27 REVIEW PROCESS 12.3.1 Community Involvement . • The USAF has maintained a public involvement and information program for the ERP since 1990 '. and maintains an Administrative Record as required by CERCLA. The Administrative Record is maintained at the Environmental Flight, 3466 North Carolina Avenue, Joint Base Andrews. For the convenience of the public, a copy of the Administrative Record is maintained in an Information Repository located at:

Prince George's County Memorial Library-Surratts-Clinton Branch 9400 Piscataway Road Clinton, MD 20735

Community involvement activities for this five-year review consisted of publishing a notice in two local newspapers announcing the USAF's intent to perform the five-year review and providing information where and how the public could obtain additional information. The notice appeared in the Prince George's County Gazette on December 3, 2009, and in the Capital Flyer on December 18, 2009. A copy of the notice is provided in Appendix A.

12.3~2 Document Review •

This review induded review of the following documents:

• Final Phase I Remedial Investigation Report, Site SS-27 (Former AOC 31 (Tetra Tech, 2007) • Final Phase n Remedial Investigation for Site SS-27 (URS, 2009a) • Prelim.i..D.ary Draft Feasibility Study (URS, 2009b) • General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland (PBS&J,2009)

12.3.3 Site Inspection

The SS-27 site was viewed on October 21, 2009. The inspection confirmed general site conditions and current land use assumptions.

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12.3.4 Interviews • No interviews were conducted with community members in regard to SS-27. A public notice was published in' two area newspapers in December 2009, indicating that the reView process was underway and providing contact information for questions or comments. No inquiries from the general public were received. Input on the review process was obtained from representatives of the USEPA, MDE, and Prince George's County through their participation in the Tier 1 partnering team and by their review of preliminary drafts of this document.

12.4 SS-27 TECHNICAL ASSESSMENT

A remedy for SS~27 has not been selected or implemented; therefore, its function could not be assessed. A screening-level risk assessment identified potential human health risk from exposure to surface soil and groundwater. It is noted, however, that the BGP identifies SS-27 as an active ERP site (PBS&J; 2009). Therefore, a Waiver-to-Construct is required for all proposed construction at the site (API 32-1021). A Waiver-to-Construct means the proposed construction has been evaluated with respect to site activity and environmental risks proposed by the construction and ultimate use of the facility.

• In addition, groundwater is prohibited from being used for potable purposes anywhere on Base (PBS&J, 2009) and COMAR 26.03.01.05 prohibits installation of new water supply wells.

12.5SS-27 ISSUES

No issues were identified.

12.6 SS-27 RECOMMENDATIONS AND. FOLLOW-UP ACTIONS.

There are no recommendations for short-term actions.

12.7 SS-27 PROTECTIVENESS STATEMENT

A remedial action has not been selected for SS-27; therefore, a protectiveness statement cannot be made.

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12.8 SS-27 NEXT REVIEW Additional five-:year reviews are anticipated. The next review will be performed within five years • of the completion. of this five-year review report. The completion date is the date of the signature shown on the signature cover attached to the front of this report.

12.9 SS..,27 REFERENCES

EEG (Ellis Environmental Group), 2005. Preliminary Assessment/Site Inspection Report AOC 31, Andrews APB, December.

PBS&J, 2009. General Plan Update - Joint Base Andrews-c-Naval Air Facility Washington, Maryland, December.

Tetra Tech, Inc., 2007. Final Phase I Remedial Investigation Report, Site SS-27 (Former AOC 31), Andrews APB, Maryland, November.

URS, 2009a. URS Corporation. Final Phase II Remedial Investigation for Site SS-27, Andrews Air Force Base, Maryland, February. URS, 2009b. Preliminary Draft Feasibility Study, February. •

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13.0 SS-28 FlVE-YEAR STATUS REVIEW • The SS-28, Building 1206, Site is an ERP site that is in the CERCLA process at Joint Base Andrews. ~S-28 was formerly designated AOC 32. The SS-28 Site is in the RI phase. The ROD for SS-28 has not been developed, and ROD mandated remedial actions have not been identified or initiated. Remedy in place is scheduled for 2012. Therefore, this review is a status review that does not fully address all the review elements in USEPA's Comprehensive Five-Year Review Guidance (USEPA, 2001).

13.1 SS-28 DESCRIPTION AND CHRONOLOGY

SS-28 is located on the west side of Joint Base Andrews at the intersection of Arnold Avenue and South Dakota A venue, has been an active military gasoline service station since 1980, and was once a maintenance facility for Base fire trucks. The site is dominated by Building 1206 and two

fuel islands. It is covered with a mixtur~ of concrete and asphalt pavement as well as unpaved, manicured areas. Figure 13.1 shows the location of SS-28.·

Historically, the site\ contained a 1,000-gallon fuel oil UST; a 25,000-gallon gasoline UST; two hydraulic lifts; a 6,000-gallon diesel UST; a 15,000-gallon diesel UST; a 250-gallon waste oil AST • (solid waste management unit [SWMU] 2); and a hazardous waste storage area (SWMU 40). SWMU 40 reportedly received antifreeze, transmission oil, and waste oil. In 2007, the site

contained a 20,000-gallon·gasoline.UST and 20,000~gallon diesel UST (HGL, 2007).

Tank and related pipeline testing in September 1991 detected the failure of a product delivery line connecting the 6,000-gallon diesel UST and the dispensing station. Joint Base Andrews responded by isolating, repairing, .and re-testing the lines connecting the 6,000-gallon and 15,000-gallon diesel USTs and the dispensing station. Five soil samples were obtained after the repair of the product delivery lines in 1992 and analyzed for BTEX and TPH - DRO. Benzene and ethylbenzene were not detected in any of the soil samples. The maximum detected concentrations of toluene, xylenes, and TPH-DRO were far below the applicable MDE action levels (HGL, 2007).

As reported in the 2007 PAlSI, the 25,000-gallon MOGAS UST and the 6,000-gallon and 15,000­ gallon diesel USTs were removed on November 6, 1998. The 1,000-gallon fuel oil UST was removed on January 29, 1999. Each of the USTs had passed Tracer Tight® leak tests in 1995, 1996, and 1997. The 25,000-gallon MOGAS tank and the 1,000-gallon fuel oil UST were coated • 197 P:\ProjectsIAndrews AFB EnvironmentallFive-year reviewsl4.0 _DeliverablesI4.1_ ReportslFinallAndrewsAFB _ 5-Yr Review_Revised March 201l.doc Joint Base Andrews - First Five- Year Review November 2010 MACTEC Engineering and Consulting. Inc. Project Number 3350092494 (Revised March 2011) with a material containing PCBs and were disposed of at a Toxic Substances Control Act (TSCA) landfill. Approximately 60 tons of excavated soil was disposed of off Site as non-hazardous, petroleum-contaminated soil. Closure reports were completed in 1999. •

After the removal of the 25,000-gallon MOGAS UST and the 6,000-gallon and 15,000-gallon diesel USTs on November 6, 1998, soil samples showed elevated 'concentrations of BTEX, TPH­ DRO, TPH-GRO, lead, and Arochlor-1254. Benzene; TPH-DRO, TPH-GRO, and Arochlor-1254 exceeded MDE residential and industria] RBCs (HGL, 2007). An analysis of the coatings of.the

1,000~gallon fuel oil tank, which was removed on January 29, 1999, and the 25,000-gallon MOGAS UST, revealed maximum PCB concentrations of 312 and 1,680 mg/kg, respectively. These concentrations were higher than the current MDE RBCs and the then current TSCA regulatory level of 50 mg/kg (EEG, 2006).

The two hydraulic lifts were removed in 1997. The approximate volume of free hydraulic fluid in the two pits was 250 gallons in the first pit and 75 gallons in the second pit. Soil samples taken after the lifts were removed revealed the presence of TPH, and the contaminated soil was subsequently removed. Samples collected from the pits following soil removal indicated that TPH concentrations did not exceed MDE standards. Soil and groundwater samples were obtained during the 2005 P AlSI in the vicinity of the former and current USTs and hydraulic lifts .. Analysis • of these soil and groundwater samples revealed the presence of petroleum-related constituents above RBCs in the vicinity of the USTs; total lead concentrations in groundwater were also above standards.

A chronology of remedial studies, investigations, and reports at SS-28 is presented below.

• 1991 to 1992: Detection and repair offailed delivery line at diesel UST • Removal of hydraulic lifts • 1998: Removal of 25,000-gallon MOGAS UST and 6,000-and 15,000-gallon diesel USTs • 1998: Excavation and disposal of approximately 60 tons of petroleum contaminated soil • 1999: Removal of 1,000-gallon fuel oil UST • 2004: Preliminary Assessment/Site Investigation (EEG, 2005) • 2007: Preliminary Assessment/Site Investigation Phase I RI (HGL, 2007)

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13.2 SS-28 BACKGROUND • 13.2.1 Physical Characteristics The SS-28 site is dominated by Building 1206 and two fuel islands. It is covered with a mixture of concrete and asphalt pavement as well as unpaved, manicured areas. The ground surface at SS-28 is nearly level with little slope. The ground elevation ranges from approximately 276 to 278 feet.

The portions of SS~28 lying beneath pavement are underlain by a 14- to 16-foot thick sequence of hard clay with varying amounts of sand and silt. Beneath the clay, a sequence of fme to medium­ grained, gray to pale yellow sand is present to a depth of 42 feet bgs. Beneath the sand, dark gray clay was encountered to the maximum explored depth of 45 feet bgs. Groundwater was recorded approximately 19 to 23 feet bgs. Groundwater is flowing in an east/southeast direction, based on permanent monitoring wells installed dUring the 2007 P A/SI (HGL, 2007).

13.2.2 Land and Resource Use

The SS-28 site IS an active gas station in an unrestricted access area at Joint Base Andrews. Surrounding land use includes aircraft operations and maintenance and administrative activities. Future land use is designated as aircraft operations and maintenance in the BGP (PBS&J, 2009); ,,-

There are no potable water supply wells located at Joint Base Andrews, including SS-28, and there is no current use or exposure to groundwater. Groundwater at SS-28 is not expected to be used for such purposes in the future. Joint Base Andrews is currently served by public water supplied by the WSSC, and, according to COMAR 26.03.01.05, wells cannot be installed in areas where public water infrastructure is available.

No areas of archaeological or historical importance have been identified at SS~28.

13.2.3 Contaniination Assessment

Soil samples collected during the 2007 P A/SI were analyzed for a full suite of contaminants (VOCs, SVOCs, metals, PCBs, GRO, and DRO). VOC concentrations were well below residential and industrial screenirig levels. Chloroform, carbon tetrachloride, and TCE were detected at

• 199 P:\Projec\S\Andrews AFB Environmental\Five-year reviews\4.0 _ Oeliverables\4.I_Reports\Final\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineerillg and Consulting, fnc. Project Number 3350092494 (Revised March 20lf) concentrations exceeding the SSLs for protection of groundwater at a dilution attenuation factor of 20. • Other than VOCs, metals were the only soil analytes detected above screening values in the samples submitted to the ·fixed-based laboratory. Aluminum, arsenic, iron, and vanadium exceeded the residential screening level in all samples collected. The 2007 P NSI concluded that the metals concentrations were likely representative of background.

In groundwater, 2007 P NSI data indicate petroleum-related constituents above MCLs are limited to the area near the present fuel island where petroleum contamination was known to exist from the , previous P NSI.

The 2007 PNSI groundwater data indicated the· chlorinated VOCs carbon tetrachloride, chloroform, and TCE are widespread across the site and often exceed MCLs. The highest monitoring well concentration of TeE (92.8 f..lglL) was detected cross-gradient, but in close proximity to SWMU 2. The second highest concentration was detected hydraulically downgradient of SWMU 2. The highest monitoring well concentrations of carbon tetrachloride (1,000 f..lglL) and chloroform (348 f..lglL) were found downgradient ofSMWU 40. • TPH-GRO was detected in two wells, at 0.323 and 2.2 f..lglL, respectively. The highest concentration was near the present fuel island where, from the previous PNSI, petroleum contamination was known to exist.

Of the six wells sampled, only one contained metal cOncentrations in groundwater that exceeded screening levels. Vanadium was detected at a concentration of 4.6 J f..lglL in the unfiltered sample, above the RBC of 3.65 f..lglL. In the filtered sample, vanadium was only detected at a concentration of 2.8J.This suggests that the vanadium detection in the unfiltered sample may be a result of turbidity or an artifact of suspended/settleable solids (HGL, 2007). The P NSI concluded that metals concentrations were not indicative of site-related contamination.

The nature and extent of contaminants in the groundwater also suggests that contaminant migration along utility lines, or periodic reversals in groundwater flow, may be occurring in this area,given the widespread presence of low levels of carbon tetrachloride and chloroform upgradient of SWMU 40 and throughout the site (HGL, 2007). 200 • P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0 _Deliverables\4.I_Reports\Final\AndrewsAFB _ 5-Yr Review_Revised March 2011.doc Joint Base Andrews - First Five-Year Revie'tv November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

13.2.4 Risk Summary • The 2007 P AlSI did not perform a risk assessment for SS-28. However, the Draft Supplemental Investigation Work Plan (URS, 2008) compared both mobile- and fixed-base-laboratory analytical .soil data from the 2007 PAIS I to USEPA Region III RBSLs and SSLs and identified chloroform and carbon tetrachloride as exceeding their risk-based SSLs for protection of groundwater. Direct exposure RBSLs were not exceeded. Several metals (aluminum, arsenic, iron, and vanadium) also exceeded RB SLs calculated for a target cancer risk of 1x 10-6 and/or a non-cancer target HQ qf 0.1, but were less than background UTLs. Based on this comparison, the Work Plan concluded that no analytesfrom the vadose zone samples would have been retained for quantitative analysis in a risk assessment and consequently that exposure to soil would not present an unacceptable risk (URS, 2008).

This screening level comparison was reviewed as part of this five-year review, and no changes were identified in screening values that would change the conclusion of the Draft Supplemental Investigation Work Plan.

• Benzene, 1,2-DCE, carbon tetrachloride, chloroform, and TCE all exceeded MCLsin samples from one or more monitoring wells, indicating potential risk if site groundwater were to be used as a potable water supply.

13.3SS-28 REVIEW PROCESS

13.3.1 Community Involvement

The USAF has maintained a public involvement and information program for the ERP since 1990 and maintains an Administrative Record as required by CERCLA. The Administrative Record is maintained at the Environmental Flight,3466 North Carolina Avenue, Joint Base Andrews. For the convenience of the public, a copy of the Administrative Record is maintained in an Information Repository located at:

Prince George's County Memorial Library-Surratts-Clinton Branch 9400 Piscataway Road Clinton, MD 20735

• 201 P:IProjects\Andrews AFB EnvironmentallFive-year reviewsl4.0 _ OeliverablesI4.1_ ReportslFinal\AndrewsAFB _5-Yr Review _Revised March 2011.doc Joint Base Andrews - First Five-Year ReviIM' November 2010 MACTEC Engineering alld Consulting, Inc. Project Number 3350092494 (Revised March 2011)

Community involvement activities for this five-year review consisted of publishing a notice in two local newspapers announcing the USAF's intent to perform the five-year review and providing information where and how the public could obtain additional information. The notice appeared in • the Prince George's County Gazette on December 3, 2009, and in the Capital Flyer on December 18,2009: A copy of the notice is provided in Appendix A.

13.3.2 Document Review

This review included review of the following documents:

• Final Preliminary Assessment/Site Investigation Report, Site SS28 (HGL, 2007) • Draft Supplementary Site Investigation Work Plan for Site SS-28 (DRS, 2008)

• General Plan ~ Update - Joint Base Andrews-Naval Air Facility Washington, Maryland (PBS&J, 2009)

13.3.3 Site Inspection

The SS-28 site was viewed on October 21, 2009. The inspection confirmed site general site conditions and current land use assumptions. • 13.3.4 Interviews

No interviews were conducted with community members in regard to SS-28. A public notice was published in two area newspapers in December 2009, indicating that the review process was underway and providing contact information for questions or comments. No inquiries from the general public were received. Input on the review process was obtained from representatives of the USEPA, MDE, and Prince George's County through their participation in the Tier 1 partnering team and by their review of preliminary drafts of this document.

13.4 SS-28 TECHNICAL ASSESSMENT

A remedy for SS-28 has not been selected or implemented; therefore, its function could not be assessed. A screening-level risk assessment identified potential human health risk from exposure to surface soil and groundwater. It is noted, however, that the BGP identifies SS-28 as an active ERP site (PBS&J, 2009). Therefore, a Waiver-to-Construct is required for all proposed construction at the site (API 32-1021). A Waiver-to-Construct means the proposed construction 202 • P:\Projects\Andrews AFB EnvironmentallFive-year reviews\4.0_Deliverables\4.I_ReportslFinal\AndrewsAFB _5-Yr Review_Revised March 2011.doc Joint Base. Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

has been evaluated with respect to site activity and environmental risks proposed by the • construction and ultimate use of the facility. In addition, groundwater is prohibited from being used· for potable purposes anywhere on Base (PBS&J, 2009) and COMAR 26.03.01.05 prohibits installation of new water supply wells.

13.5 SS-28 ISSUES

No issues were identified.

13.6 SS-28 RECOMMENDATIONS AND FOLLOW-UP ACTIONS

There are no recommendations for short-term actions.

13.7 SS-28 PROTECTIVENESS STATEMENT

I A remedial action has not been selected for SS-28; therefore, a protectiveness statement cannot be made.

• 13.8 SS.,.28 NEXT REVIEW . Additional five-year reviews are anticipated. The next review will be performed within five years of the completion ofthis five-:year review report. The completion date is the date of the signature shown on the signature cover attached to the front of this report.

13.9 SS-28 REFERENCES

EEG (Ellis Environmental Group), 2006. Final Preliminary Assessment/Site Inspection Report, AOC 32, Including SWMUs 2 and 40, Andrews Air Force Base, MD, May.

HGL (HydroGeologic, Inc.), 2007. Final Preliminary Assessment/Site Investigation Report, Site SS28, Andrews AFB, Maryland, October.

PBS&J, 2009. General Plan Update - Joint Base Andrews-Naval Air Facility Washington, Maryland, December.

URS, 2008. Draft Supplementary Site Investigation Work Plan for Site SS-28, Andrews AFB, "' Maryland, December.' .

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Legend Figure 3.1 -$- Monitoring Well D Existing AST / UST ST-10 Site Map D Area Requiring Institutional Controls r::J Former AST / UST N - Security Fence ! o~~~6.oiiiiiiiiiiiiiiiiiiiiiiiiil12 0 2010 Five-Year Review " c: 'Feet Joint Base Andrews, Maryland ~p_r_ep~a_re~d_/D_a~te_: ~B_R~P~O~3/~1_7/_11~~C~he~c~ke_d_/D_a~te~: ~J~EB__03_1_17_/1_1-L ______~ ______~______~~ __------~ ~J\CTEc: Document P:\Projects\Andrews AFB EnvifonmentaI\GIS\MapDocuments\2010 Five -Year RevieW\ST10_ ST14_11x17LS.mxd PDF : P:\Projects\Andiews AF B Environmental\Five-year re views\ • .O_Oe lfverables\4.' _Reports\Finaf\New Fig l-t .pdf 03/ 1712 011 10:09 AM jebrandow • • • co I.() ~ 60 r--ro 0 6 I.() '" ..... 50 -- f------OJ .0 E :::J c:: t5 OJ -\ "e ...J 40 - ~ Cl... -C) :::I c: ...... 0 0 c: ~ ...... 0 ---- ~ 30 \ ;\ N ...ItS "- c: ~ co -G) "' - U 20 ~ .0 \ \ >­ .0 "0 OJ c:: .::£ () :i: OJ ~~ C1l ( ...... c:: \\ 0 U 10 - - " ~~ / / ~\ y ..(). __ ....-A'...... I 0-- -:--- ~ ...... ~ ..r... -1K ~ ~~ ~ ~ ~ -a-.. I o - ,~ -- ~ ~ , ~ , ~ 7 7 7 7 7 7 7 7 7 7 7 ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ Date ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ l· MWO I -STlO ___-- MW---02---ST I-O---o-----..:..MWO3---ST-I-O-----7f-- -MW--O--4 - S-T-IO----~ M-W-O-6-S-T-l O- --'---M- W--Og--S-T-l O------MW- -O9- --ST­ -IO ~MWIO - STIO -o- MWI2-ST I O .. MWI3-STIO -D- MWI4-STIO -t:I- MWlS-STlO -t:I- MWI6-STlO ------~

Joint Base Andrews 6 MACfEC Maryland Figure 3.2 ST-10 Benzene Concentrations over Time in Groundwater 2010 Five-Year Review Joint Base Andrews, Ma land

P:\ProjectslAndrews AFB Environmental\Five-year reviewsI4.0_DeliverablesI4. I_RepOrlsIFinaIlFiguresIFig 3_5_ 1 and 3_5_2 ST lOB and N - Fig ST 10 (Benzene) • • • " "

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P:\Projects\Andrews AFB EnvlronmentaJ\Five-year reviewsI4.0_DeJiverabJesI4.I_Repon s\F inaJ\Figures\Fig 3_5_1 and 3_5_2 ST IO B and N - Fi g STIO (Naphth ) •

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Legend Figure 4.1 Note: ST-14 Site Map Contamination isoconcentration contours based -$- Monitoring Well -+- Approximate Direction of Groundwater Flow on March 2006 data as depicted in ST-14 ROD Approximate Area Requiring Institutional Controls TCE Concentration in Groundwater (ugfL) and Final ST-14 Pre-Design Study Report. c::::J N i~ Base Boundary -- Carbon Tetrachloride in Groundwater (ugfL) • ! O~~~15IiiiiiO iiiiiiiiiiiiiiiiiiiiii.300 - Benzene in Groundwater (ugfL) 2010 Five-Year Review " c 'Feet Joint Base Andrews, Maryland Prepared/Date: BRP 04/27/10 Checked/Date: SWR 04/27/10 MACTEC Do cument P:\Projects\Andrews AF B EnvironmentaI\GIS\MapDocuments\2010 Five-Year Review\Sn O_ST14_11x17LS.mxd PD F: P:\Projects\Andrews AFB Environmentaf\Five-year reviews\4.0_Deiverables\4.1_Reports\Final\Figures\Figure 4.1.pdf 041271201 0 8:07 AM brpeters •

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Legend Figure 7.1 -$ Monitoring Well FT-03 Site Map ~-.J Approximate Site Boundary N -.. Approximate Direction of Groundwater Flow • o~~~lOliiioiiiiiiiiiiiiiiiiii.2 00 2010 Five-Year Review • A c: 'Feet Joint Base Andrews, Maryland ~P-re~pa7r~~~ed / D~~at e~:B~R-P~04 ~~/ 27-1-10~=C~he~c7k-ed_I_D~at=e:~s=WR~-O~4/~2~7/~10~~~~~~~~~~~~~~~--~~77~~~~~~--~~~~~~~~~------~ ~i\CTEc: Document: P:\Projects\A.ndrews AFB EnYironmenlal\G IS\MapDocuments\2010 Five-Year Review\FT03_lF07_11 x17 LS.mxd PDF: p :\Projeds\Andrews AFB Environmental\Five·year re"';ews\4 . 0_De l iverab~s\4 . 1 _ Reports\Fina l \FlQures\FiQure 7. t .pdf 04 127/2010 8:19 AM brpeters • I* ::; « ~ 0 i i .;. 0 C> ~ tg ~ £ ~ 0: I :i- ~ ~ ~ ~I i . ~ ~ ..~ "E ~ E ~ W III • «U. !

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Legend Figure 8.1 !:..--1 Extent of Landfill Activities LF-05 Site Map o Area Requiring Institutional Controls N - AAFB Boundary Fence • ! 0 150 300 2010 Five-Year Review lo l-=-A_~i~~~~~;;;~._."T'F_ee_t ______-, Joint Base Andrews, Maryland o ....P_r..,:ep__are_d/_D,;..at..;.,e:_B_R_P_04___127/ 1..;,O..&...;C..;.,he...,;c...ke;;,,;d ;..;/D;.;.a..,;te_: S:..W..;.,R..;.,:..04..,;/2;,.;.7.../1 ,;;. 0 L-______P MACTEC •

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m ~ ~ ~ o § 11 ! ~ ~ ~ 10 I ~------~ ~ Legend Figure 9.1 ~ D Extent of Landfill Activities LF-06 Site Map ~ ~ ~:J Approximate Site Boundary iN --+- Approximate Direction of Groundwater Flow ·0 • ~ • O~~~1~50iiiiiiiiiiiiiiiiiiii.300 2010 Five-Year Review ~ 1-""__c______..,!F_e_et ______-, Joint Base Andrews, Maryland 8 ~Pr~e~pa~re~d~/ D~a~te~: _BR_P_O~4~/2~7~/ 1~O ~C~h~ec~k~ed~/ D~a~te~: ~SW~R~O~4/~27~/~10J-______~ ~i\C:llEC: •

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Legend Figure 10.1 LF-07/BLNA Site Map o Extent of Landfill Activities --.. Approximate Direction of Groundwater Flow N • A O~I~~~1~5~Oiiiiiiiiiiiiiiii~~~eet 2010 Five-Year Review Joint Base Andrews, Maryland Prepared/Dale: BRP 04/27/10 Checked/Dale: SWR 04/27/10 MACTEC Document: P:\Projects\Andrew5 AFB Environmental'GIS\MapDocumenls\2010 Five·Year Review\FT03_LF07_11x17LS.mxd PDF : P:\Projeds\Andrews AFB Environmental\Five·year reviews\4.0_Deliverables\4.'_Reports\Final"Ftgures\Figure 10.1.pdf 0,(/27/2010 8:21 AM brpete rs •

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• Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011) •

TABLES

•

P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0 _ Deliverables\4.1_ Reports\Final\AndrewsAFB _5-Yr Review_Revised March 20 I I.doc· Joint Base Andrews - First Five- Year Review November 20 10 MACTEC Engineering and Consulting, Inc. Table 2.1 FT -04 Groundwater Monitoring Data Summary

• Site ID: FT04 FT04 FT04 FT04 FT04 FT04 FT04 FT04 FT-04 Location ID: MW0302-FT04 MW0302-FT04 MW0302-FT04 MW0302-FT04 MW0302-FT04 MW0302-FT04 MW0302-FT04 MW0302-FT04 MW0302-FT04 Sample ID: Regulatory MW03FT04-02-02 MW0302FT4GW6062 MW0302FT4GW6229 MW0302FT4GW6306 MW0302FT04GW6378 MW0302FT04GW6527 MW0302FT04GW6674 MW0302FT04GW6704 MW0302FT04GW6742 Sample Date: Standard 04/16/2004 06/16/2006 09/12/2006 03/30/2007 10/24/2007 05/2112008 12117/2008 03110/2009 9117/2009 Sample Type: Sample Sample Sample Sample Sample Sample Sample Sample Sample

.- Notes: Regulatory Standards are groundwater Site Remediation Goals (SRGs) from Final Record of Decision, FT04, (USAF, US EPA, and MDE,2005) mg/L = milligrams per liter ug/L = micrograms per liter Data reported prior to 2006 was not collected by MACTEC and cannot be verified Data collected after 2005 have been validated and checked by MACTEC < = Many laboratory detection limits reported prior to 2006 cannot be verified as to whether they are Reporting Limits or Method Detection Limits, therefore, to maintain' the best possible consistent non-detect values, the Reporting Limit is being represented for data collected after 2005

Data Flag Definitions:

B = Blank contanlination: The analyte was found in an associated blank above 112 the ReportingLimit, as well as in the sample D = Sample result is a dilution F = Found: The analyte was positively identified but the associated concentration is an estimation above the Method Detection LinJit and below the Reporting Limit J = The analyte was positively identified; the quantitation is an estimation M = The result is estimated due to a matrLx effect NA = Not Analyzed UJ = The analyte was not detected; however, the result is estimated due to discrepancies in meeting certain analyte-specific quality control criteria L@l,rDT.;Ex~~l!:E(m1t@lQii~rs~~~Y~,@~JL.·. '.. MACTEC Project: 3350092494 Prepared by: M. Barker 01/26/10 Checked by: C. Crow 01127110 P:IProjectslAndrews AFB EnvironmentallFive-year reviewsI4.0_Deliverob\esI4.\_ReportsIFina\ITab\es\2.\ FT04-BY WELL \-28-\0 Page 1 of 11 Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Table 2.1 FT -04 Groundwater Monitoring Data Summary

• Site ID: FT05 FT04 FT04 FT04 FT04 FT04 FT04 FT04 FT-04 Location ill: MW0304-FT05 MW0304-FT04 MW0304.-FT04 MW0304-FT04 MW0304-FT04 MW0304-FT04 MW0304-FT04 MW03 04-FT04 MW0304-FT04 Sample ID: RegulalOry MW03FT04-04-02 MW0304FT4GW6061 MW0304FT4GW6228 MW0304FT4GW6305 MW0304FT04GW6379 MW0304FT04GW6528 MW0304FT04GW6603 MW0304FT04GW6705 MW0304FT04GW6743 Sample Date: Standard 4116/2004 06115/2006 09/12/2006 03/30/2007 10/24/2007 05/2112008 09/1712008 03/09/2009 911712009 Sample Type: Sample Sample Sample Sample Sample Sample Sample Sample Sample

Notes: Regulatory Standards are groundwater Site Remediation Goals (SRGs) from Final Record ofDecision, FT04; (USAF, US EPA, and MOE,2005) mgIL = milligrams per liter ugIL = micrograms per liter Data reported prior to 2006 was not collected by MACTEC and cannot be verified Data collected after 2005 have been validated and checked by MACTEC < = Many laboratory detection limits reported prior to 2006 cannot be verified as to whether they are Reporting Limits or Method Detection Limits, therefore, to maintain the best possible consistent non-detect values, the Reporting Limit is being represented tor data collected after 2005

Data Flag Definitions:

B =Blank contamination: The analyte was found in an associated· blank above 112 the Reporting Limit, as well as in the sample D =Sample result is a dilution F = Found: The analyte was positively identified but the associated concentration is an estimation above the Method Detection Limit and below the Reporting Limit J =The analyte was positively identified; the quantitation is an estimation M = The result is estimated due to a matrix effect NA = Not Analyzed UJ = The analyte was not;detected; however, the result is estimated due to discrepancies in meeting certain analyte-specific quality control criteria l~s~1E~(:EIII~.~Q[(;AiQ~Yllil;~~J)~!@JBi:~lifJ MACTEC Project: 3350092494 Prepared by: !'vi. Barker 01126/10 Checked by: C. Crow 01/27/10 • P:IProJectslAndrews AFB EnvironmentallFive-year reviewsI4.0_Deliverab\esI4.\_ReportsIFina\ITab\esI2.\ FT04-BY WELL \-28-\0 Page 2 of II Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Table 2.1 FT-04 Groundwater Monitoring Data Summary

Site ID: FT04 FT04 FT04 FT04 FT04 FT04 - FT04 FT04 FT-04 Location 10: MW0401-FT04 MW0401-FT04 MW0401-FT04 MW0401-FT04 MW0401-FT04 MW0401-FT04 MW0401-FT04 MW0401-FT04 MW0401-FT04 Sample ID: Regulatory MW04FT04-0 1-02' MW0401 FT4GW6056 MW040lFT4GW6223 MW040lFT4GW6300 MW040lFT04GW6380 MW040I FT04GW6529 MW040I FT04GW6604 MW040lFT04GW6706 MW0401FT04GW6744 Sample Date: Standard 04116/2004 06/1312006 09/12/2006 03/28/2007 10/2612007 05/22/2008 0911812008 03110/2009 9/17/2009 Sample Type: Sample Sample Sample Sample Sample Sample Sample . Sample Sample

Metals - SW846 6010 6010B (Dissolved), m!!/L IArsenic I 0.01 NA I NA I NA I 0.0046 F I NA I NA I NA I NA I < 0.Q3 1 IManganese l~oi'l59'?\~ NA I NA 1 NA I NA 1 NA 1 NA I NA I NA 1'1;}~'1~};si(ofS5,./~iBl

Metals - SW846 6010 6010B (Total), m!!/L IArsenic I 0.01 0.0094 F I NA I NA I NA I <0.01 I <0.01 I 0.0053 F I < 0.03 1 NA I " IManganese 1>:do.lS9",;'sj ;h,;i:; ;~;0.468S!' 1 NA I NA 1 NA I»·: <0!34 .:.: ,s;~~·> . .. I;;;:;:~ 0[6 (~hl: I' ,~::~~ .':: 0;34\.:i>'.. )?:&J .:as . 0.35;<' ,<:: I NA 1

Metals - SW846 6020 (Dissolved), m!!/L 1Arsenic 1 0.01 NA 1 NA 1 NA 1 NA 1 NA 1 NA 1 NA 1 NA I NA 1 IManganese 1~(jrf59'YB:\¥! NA J NA 1 NA I NA I NA 1 NA 1 NA 1 NA 1 NA I

Metals - SW846 6020 6020A (Tota\). m!!/L IArsenic I}:;'0'(j.oC·::~ NA I 0.006 I 0.0081 I NA I NA 1 NA I NA 1 NA 1 NA I ~(j;55 ....• . . :~~.~~.~ ," 1Manganese ISO.tS9;.!&' NA IIl&Yjf:",'0;45 kM.:" ~~-·I{· "~ ,I NA I NA I NA I NA I NA I NA I

Volatile Ol1!:anic Compounds - SW846 8240 8260 8260B U!!/L 1Benzene 1'•• 'S"?il: <0.4 1 0.16 F I <0.4 1 <0.4 1 <0.4 I <0.4 1 <0.4 I <0.4 I '<0.4 ICarbon tetrachloride I;;Wlh, 5;:;/11 <2.1 I < I 1 < 1 I

Notes: Regulatory Standards are groundwater Site Remediation Goals • (SRGs) from Final Record of Decision, FT04, (USAF, US EPA, and MOE(2005) mgIL = milligrams per liter ugIL = micrograms per liter Data reported prior to 2006 was not collected by MACTEC and cannot be verified Data collected after 2005 have been validated and checked by MACTEC < = Many laboratory detection limits reported prior to 2006 cannot be verified as to whether they are Reporting Limits or Method Detection Limits, therefore, to maintain the best possible consistent non-detect values, the Reporting Limit is being represented for data. collected after 2005

Data Fiag Definitions:

B = Blankcontamination: The analyte was found in an associated blank above 112 the Reporting Limit, as well as in the sample D = Sample result is a dilution F = Found: The analyte was positively identified but the associated concentration is an estimation above the Method Detection Limit and below the Reporting Limit J = The analyte was positively identified; thequantitation is an estimation M = The result is estimated due to a matrix effect NA_= Not Analyzed UJ = The analyte was not detected; however, the result is estimated due to discrepancies in meeting certain analyte-specific quality control criteria ~REs~IE:x.:~~~S~EGij!d~:rO~Y'"STAND~i!llilLi~s MACTEC Project: 3350092494 Prepared by: M. Barker 01126110 Checked by: C. Crow 01127/10 • P:\ProjectsIAndrews AFB EnvironmentallFive-year reviewsI4.0_DeliverablesI4.I_Repol1sIFinaIITablesI2.1 FT04-BY WELL 1-28-10 Page 3 of II Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Table 2.1 FT -04 Groundwater Monitoring Data Summary

Site ID: FT04 FT04 FT04 FT04 FT04 FT04 FT04 FT04 FT04 Location ID: MW0402-FT04 MW0402-FT04 MW0402-FT04 MW0402-FT04 MW0402-FT04 MW0402-FT04 MW0402-FT04 MW0402~FT04 MW0402-FT04 Sample 10: Regulatory MW0402FT4GW6064 MW0402FT4GW6065 MW0402FT4GW6231 MW0402FT4GW6232 MW0402FT4GW6308 MW0402FT4GW6309 MW0402FT04GW6530 MW0402FT04GW6531 MW0402FT04GW6675 Sample Date: Standard 06/16/2006 06/16/2006 0911212006 0911212006 03/3012007 0313012007 05/21/2008 05/2112008 12117/2008 Sample Type: Sample Duplicate Sample Duplicate Sample Duplicate Sample Duplicate Sample

Notes: Regulatory Standards are groundwater Site Remediation Goals • .. (SRGs) from Final Record ofDecision, FT04, (USAF, USEPA, and MDE,2005) mg/L = milligrams per liter ug/L = micrograms per liter Data reported prior to 2006 was not collected by MACTEC and cannot be verified Data collected after 2005 have been validated and checked by MACTEC < = Many laboratory detection limits reported prior to 2006 cannot be verified as to whether they are Reporting Limits or Method Detection Limits, therefore, to maintain the best possible consistent non-detect values, the Reporting Limit is being represented for data collected after 2005

Data Flag Definitions:

B = Blank contamination: The analyte was found in an associated blank above 112 the Reporting Limit, as well as in the sample D = Sample result is a dilution F = Found: The analyte was positively identified but the associated concentration is an estimation above the Method Detection Limit and below the Reporting Limit J = The analyte was positively identified; the quantitation is an estimation . M = The result is estimated due to a matrix effect NA = Not Analyzed UJ = The analyte was not detected; however, the result is estimated due to discrepancies in meeting certain analyte-specific quality control criteria ;[¢iTj~T!ixsji:F:'!l.$~~9"(j!At9.RY,~~NPt\~~·.;·ff,·~~~=:~:] MACTEC Project: 3350092494 Prepared by: M. Barker 01126/10 '. Checked by: C. Crow 01127110 P:IProjectslAndrews AFB EnvironmentallFive-year reviewsI4.0_DeJiverablesI4.I_ReportsIFinaI\Tables\2.1 FT04-BY WELL 1-28-10 Page 4 of II Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc~ Table 2.1 FT-04 Groundwater Monitoring Data Summary

• Site ID: FT04 FT04 FT-04 FT-04 FT04 FT04 FT04 FT04 FT04 Location ID: MW0402-FT04 MW0402-FT04 MW0402-FT04 MW0402-FT04 MW0403-FT04 MW0403-FT04 MW0403-FT04 MW0403-FT04 MW0403-FT04 Sample ID: Regulatory MW0402FT04GW6707 MW0402FT04GW6708 .MW0402FT04GW6745 MW0402FT04GW6746 MW0403FT4GW6063 MW0403FT4GW6230 MW0403FT4GW6307 MW0403FT04GW6532 MW0403FT04GW6606 Sample Date: Standard 03/10/2009 03/10/2009 9117/2009 9117/2009 06/15/2006 09/12/2006 03/30/2007 05/22/2008 09/19/2008 Sample Type: Sample Duplicate Sample Duplicate Sample Sample Sample Sample Sample

Notes: Regulatory Standards are groundwater Site Remediation Goals • (SRGs) from Final Record ofDecision, FT04, (USAF, USEPA, and MDE.2005) mg/L= rnilligrams per liter ug/L = micrograms per liter Data reported prior to 2006 was not collected by MACTEC and cannot be verified Data collected after 2005 have been validated and checked by MACTEC < = Many laboratory detection limits reported prior to 2006 cannot be verified as to whether they are Reporting Limits or Method Detection Limits, therefore, to maintain the best possible consistent non-detect values, the Reporting Limit is being represented for data collected after 2005

Data Flag Definitions:

B = Blank contanlination: The analyte was found in an associated blank above 112 the Reporting Limit, as well as in the sample D = Sample result is a dilution F = Found: The analyte was positively identified but the associated concentration is an estimation above the Method Detection Limit and below the Reporting Limit J = The analyte was positively identified; the quanti tat ion is an estimation M = The result is estimated due to a matrix effect NA = Not Analyzed UJ = The analyte was not detected; however, the result is estimated due to discrepancies in meeting certain analyte-specific quality control criteria (~""[(lLT E~g[~DSREq~h;(t9~Y)!~;N~@~F""_;J?r~ MACTEC Project: 3350092494 Prepared by: M. Barker 01/26/10 Checked by: C. Crow 01127110 • P:lProjectslAndrews AFB EnvironmentallFive-year reviewsI4.0_DeliverablesI4.I_ReportsIFinaIlTables12.1 FT04-BY WELL 1-28-10 Page 5 of II Joint Base Andrews - First Five- Year Review November 2010 MACTEC Engineering and Consulting, Inc. Table 2.1 FT ,.04 Groundwater Monitoring Data Summary

•• Site lD: FT04 FT04 FT-04 FT04 FT04 FT04 FT-04 FT04 FT04 Location ID: MW0403-FT04 MW0403-FT04 MW0403-FT04 MW0405-FT04 MW0405-FT04 MW0405-FT04 MW0405-FT04 MW050 I-FT04 MW0501-FT04 Sample ID: Regulatory MW0403FT04GW6607 MW0403FT04GW6709 MW0403FT04GW6747 MW0405FT04GW6524 MW0405FT04GW6599 MW0405FT04GW670 I MW0405FT04GW6748 MW-MW0501-01 MW-MW0501-31 Sample Date: Standard 09119/2008 03/10/2009 911712009 05122/2008 09118/2008 03/10/2009 9/17/2009 08117/2005 08/17/2005 Sample Type: Duplicate Sample Sample Sample Sample Sample Sample Sample Duplicate

Metals - SW846 6010 60108 (Dissolved}. melL IArsenic I 0.01 NA I NA I NA I NA I NA I < 0.03 I <0.03 I NA I NA I IManganese l~filoff59.1'~~ NA 1 NA 1 NA 1 NA I NA I?§;: ;;;:j;i~(jf,nijf.~:"'i .... :~~I~~~~4,of45JN' ".1 NA 1 NA 1

Metals - SW846 6010 60108 (Total). m!!1L IArsenic 1 0.01 0.0072 F 1 <0.03 1 <0.03 1 <0.01 1 <0.03 I NA I NA 1 NA 1 NA 1 .. IManganese llifLO.159B ",,\"1'"(i;55!f%%" ;7;;t-;1f!lt~{~¥'~?:'?(hJ9~"'~' "<'KI 0.052 :O:st"~,;r ';j)HfJft'" .0.J9g}'· ..•i~;1 NA I NA I 0.0536 I 0.0524 I

Metals - SW846 6020 (Dissolved), melL IArsenic I 0.01 NA I NA I NA I NA I NA I NA 1 NA I NA I NA I IManganese 1110:1'59' >:j;) NA 1 NA 1 NA 1 NA 1 NA 1 NA 1 NA 1 NA 1 NA 1

Metals - SW846 6020 6020A (Total), m!!1L lArsenic I~'T" 6:0 1.~;:j NA 1 NA 1 NA 1 NA 1 NA 1 NA 1 NA 1 0.000489 1 0.00046 1 IManganese li'{;-,0.159~iii NA I NA I NA I NA I NA I NA I NA I NA I NA I

Volatile Orl!anic Compounds - SW846 8240 8260 82608 ul!lL -. IBenzene 1>i'i"4¥:' .!) .in <0.4 I 0.34 F I <0.4 I 2.01 li0"iii;7f':' ·16.):H;~;<.· .' l~"'r\" ·17if"'8~'. H~~" '. f5,4~:7' ·••.$1 <0.4 I <0.4 I ICarbon tetrachloride Ir.:{' •.•• 5X)J$i < 1 1

Notes: Regulatory Standards are groundwater Site Remediation Goals (SRGs) from Final Record ofDecision, FT04, (USAF, USEPA, and MDE,2005) mgIL = milligrams per liter ugIL = micrograms per liter Data reported prior to 2006 was not collected by MACTEC and cannot be verified Data collected after 2005 have been validated and checked by MACTEC < = Many laboratory. detection limits reported prior to 2006 cannot be verified as to whether they are Reporting Limits or Method Detection Limits, therefore, to maintain the best possible consistent non-detect values, the Reporting Limit is being represented for data collected after 2005

Data Flag Definitions:

B = Blank contamination: The analyte was found in an associated blank above 1/2 the Reporting Limit, as well as in the sample b = Sample result is a dilution F = Found: The analyte was positively identified but the associated concentration is an estimation above the Method Detection Limit and below the Reporting Limit J = The analyte was positively identified; the quantitation is an estimation M = The result is estimated due to a matrix effect NA =Not Analyzed UJ = The analyte was not detected; however, the result is estimated due to discrepancies in meeting certain analyte-specific quality control criteria r~§@i'~Kg!~ps)~~:GJ;l,~~ioRilSmANp~EP.t~][ MACTEC Project: 3350092494 Prepared by: M. Barker 01126/\0 Checked by: C. Crow 0\/27/10 P:IProjectslAndrews AFB EnvironmentallFive-year reviewsI4.0_DeliverablesI4.I_ReportsIFinalITablesl2.1 Ff04-BY WELL 1-28-10 Page 6 of 1\ Joint Base Andrews - Firsl Five-Year Review November 2010 MACTEC Engineering and Consulling, Inc. Table 2.1 FT-04 Groundwater Monitoring Data Summary

• Site !D, FT04 FT04 FT04 FT04 FT04 FT04 FT04 FT-04 FT-04 Location 10: MW0501-FT04 MW0501-FT04 MW0501-FT04 MW050 I-FT04 MW050 I-FT04 MW0501-FT04 MW0501-FT04 MW050 I-FT04 MW0701-FT04 Sample !D: ReglllalOry MW050I FT4GW6066 MW0501FT4GW6233 MW050lFT4GW6310 MW0501FT04GW6384 MW050lFT04GW6533 MW050lFT04GW6608 MW050 I FT04GW67 10 MW050lFT04GW6749 MW070lFT04GW6750 Sample Date: Standard 06/16/2006 09/19/2006 03/29/2007 10/26/2007 05/22/2008 09/18/2008 03/10/2009 911712009 9/16/2009 Sample Type: Sample Sample Sample Sample Sample Sample Sample Sample Sample

Metals - SW846 6010 60lOB (Dissolved). ml!/L IArsenic I 0.01 NA I NA I <0.03 I NA I NA I <0.03 I <0.03 I NA I 0.0096 F I IManganese r .YOfI'S9"JB! NA I NA I NA I NA I NA I 0.034 I 0.048 I NA r':;!;gl.:nt4i~i'~J

Metals - SW846 6010 6010B (Totan. ml!/L IArsenic I 0.01 NA I NA L NA I 0.005 F I <0.01 I NA I NA I <0.03 I NA I .,' IManganese 1;!i!iO:159 ,-0:. NA I NA I NA I 0.038 I 0.055 I NA I NA I 0.053 I NA I

Metals - SW846 6020 (Dissolved). ml!lL IArsenic I 0.01 0.0015 F I NA I NA I NA I NA I NA I NA I NA I NA I IManganese 1;t:"01i"S9~i'i;i 0.083 M I NA I NA I NA I NA I NA I NA I NA I NA I

Metals - SW846 6020 6020A (Totan. ml!/L LArsenic \. ·.•O~OIIY?~ NA I 0.00078 F I NA I .NA I NA I NA I NA I NA I NA I IManganese 1··,:,off59·:·~:g~ NA I 0.053 I NA I NA I NA I NA I NA I NA I NA I

Volatile Orl!anic Compounds - SW846 8240 8260 8260B ul!lL IBenzene L·;,iJjt;;r .5 ..J~ <0.4 I < 0.4 I <0.4 I <0.4 I <0.4 I <0.4 I <0.4 I < 0.4 I < 0.4 I ICarbon tetrachloride I 'Y;~f'5?I 0.31 F I 0.92 F I 0.52 F I < I I < I I 0.3 F I < I I < I I

Notes: Regulatory Standards are groundwater Site Remediation Goals • (SRGs) from Final Record ofDecision, FT04, (USAF, USEPA, and MDE,2005) mgIL = milligrams per liter ugIL = micrograms per liter Data reported prior to 2006 was not collected by MACTEC and cannot be verified Data collected after 2005 have been validated and checked by MACTEC < = Many laboratory detection limits reported prior to 2006 cannot be verified as to whether they are Reporting Limits or Method Detection Limits, therefore, to maintain the best possible consistent non-detect values, the Reporting Limit IS being represented tor data collected after 2005

Data Flag Definitions:

B = Blank contamination: The analyte was found in an associated blank. above 1/2 the Reporting Limit, as well as in the sample D = Sample result is a dilution F = Found: The analyte was positively identified but the associated concentration is an estimation above the Method Detection Limit and below the Reporting Limit 1 = The analyte was positively identified; the quantitation is an estimation M = The result is estimated due to a matrix effect NA = Not Analyzed UJ = The analyte was not detected; however, the result is estimated due to discrepancies in meeting certain analyte-specific quality control criteria I~SUbl:):xcEEp.$.irliT[(JL&m~YrSTA~DA~If~" MACTEC Project: 3350092494 Prepared by: M. Barker 01126/10 . Checked by: C. Crow 01127110 • P:lProjectslAndrews AFB EnvironmentalIFive-year reviewsI4.0_DeliverablesI4.I_ReportsIFinaIITables\2.1 FT04-BY WELL 1-28-10 Page 7 of II Joint Base Andrews - First Five-Year Review November 20/0 MACTEC Engineering and Consulting, Inc. Table 2.1 FT-04 Groundwater Monitoring Data Summary

• Site !D: FT-04 FT-04 FT-04 FT-04 FT-04 FT-04 FT-04 FT04 FT04 Location 10: MW0702-FT04 MW0703-FT04 MW0704-FT04 MW0705-FT04 MW0706-FT04 MW0901-FT04 MW0901-FT04 MW8801-FT04 MW8801-FT04 Sample !D: Regulatory MW0702FT04GW675I MW0703FT04GW6752 MW0704FT04GW6753 MW0705FT04GW6754 MW0706FT04GW6755 MW0901FT04GW6720 MW090 IFT04GW6756 MW880lFT4GW6059 MW880lFT4GW6226 Siunple Date: Standard 9116/2009 911612009 9116/2009 9116/2009 911612009 6/912009 911712009 06115/2006 09/12/2006 Sample Type: Sample Sample Sample Sample Sample Sample Sample Sample Sample

Metals - SW846 6010 60108 (Dissolved), m2/L 1Arsenic 1 0.01 <0.03 1 < 0.03 1 <0.03 1 <0.03 1 NA 1 < 0.03 1 NA 1 NA 1 NA 1 1Manganese H1~'o;i59 '~;Ii'f'" ;0.25,e. ;~1_;··0.25.~~!<; ·I{~~· ().27'-~~~J;:&. 1 0.03 1 NA I 0.083 1 NA I NA 1 NA 1

Metals - SW846 6010 60108 (Total). m2/L IArsenic 1 0.01 NA 1 NA 1 NA 1 NA 1 <0.03 1 NA 1 <0.03 I NA 1 NA 1 1Manganese l,i;~\~iJ;i59lt\;.~> NA 1 NA I NA 1 NA I . i?~··i. 0.27.31ah:..1 NA I 0.09 1 NA 1 NA 1

Metals - SW846 6020 (Dissolved), m2/L IArsenic I 0.01 NA I NA I NA I NA I NA I NA I NA 1 NA I NA 1 IManganese F;'goTrS9 .... NA I NA 1 NA I NA I NA I NA I NA I NA I NA I

Metals - SW846 6020 6020A (Total). m2/L IArsenic l_O~Ol NA I NA 1 NA I NA 1 NA I NA 1 NA I 0.00024 F 1 < 0.005 I 1 . 1Manganese 1?~t();159 . .] NA 1 NA 1 NA 1 NA NA 1 NA 1 NA 1&.;/i~.0:23iM0'· :;]';11' .:~iJ!:29 .; .. ~ij.1

Volatile Or2anic Compounds - SW846 8240 8260 82608 u2/L 1Benzene I~;i' ::.:5:':'9"1 3.8 1 <0.4 I 0.83 I <0.4 I <0.4 1 2.0 1 1.1 1 <0.4 1 <0.4 1 ICarbon tetrachloride I~J 5. ;;1 1.8 I 0.41 F 1 < I 1 < I 1

Data Flag Definitions:

B = Blank contamination: The analyte was found in an associated blank above 112 the Reporting Limit, as well as in the sample o = Sample result is a dilution F = Found: The analyte was positively identified but the associated concentration is an estimation above the Method Detection Limit and below the Reporting Limit J = The analyte was positively identified; the quantitation is an estimation M = The result is estimated due to a matrix effect NA = Not Analyzed UJ = The analyte was not detected; however, the result is estimated due to discrepancies in meeting certain analyte-specific quality control criteria iRE~!I:~lfu~§]§i?S ~!t:@L11:~!!~£N.})~]iF~ { MACTEC Project: 3350092494 Prepared by: M. Barker 01126/10 Checked by: C. Crow 01127110 • P:IProjectslAndrews AFB EnvironmentallFive-year reviewsI4.0_DeliverablesI4.I_ReponsIFinalITablesI2.1 FT04-BY WELL 1-28-10 Page 8 of II Joint Base Andrews - First Five- Year Review November 2010 MACTEC Engineering and Consulting, Inc. Table 2.1 FT -04 Groundwater Monitoring Data Summary

• Site ID: FT04 FT04 FT04 FT04 FT04 FT-04 FT04 FT04 FT04 Location lD: MW8801-FT04 MW8801-FT04 MW8801-FT04 MW8801-FT04 MW8801-FT04 MW8801-FT04 MW880S-FT04 MW880S-FT04 MW880S-FT04 Sample lD: Regulatory MW880lFT4GW6303 MW880lFT04GW6374 MW880I FT04GW6523 MW880lFT04GW6673 MW880lFT04GW6700 MW880lFT04GW6739 MW8805FT4GW6060 MW880SFT4GW6227 MW880SFT4GW6304 Sample Date: Standard 03/29/2007 10/24/2007 OS/2112008 1211 712008 03/09/2009 911712009 06114/2006 09/12/2006 0312912007 Sample Type: Sample Sample Sample Sample Sam'ple Sample Sample Sample Sample

Notes: Regulatory Standards are groundwater Site Remediation Goals (SRGs) from Final Record ofDecision, FT04, (USAF, US EPA, and MOE,200S) mg/L = milligrams per liter ug/L = micrograms per liter Data reported prior to 2006 was not collected by MACTEC and cannot be verified Data collected after 200S have been validated and checked by MACTEC < = Many laboratory detection linlits reported prior to 2006 cannot be verified as to whether they are Reporting Limits or Method Detection Limits, therefore, to maintain the best possible consistent non-detect'values, the Reporting Limit is being represented for data collected after 200S

Data Flag Definitions:

B = Blank contamination: TIle analyte was found in an associated blank above 112 the Reporting Limit, as well as in the sample D = Sample result is a dilution F"= Found: The analyte was positively identified but the associated concentration is an estimation above the Method Detection Limit and below the Reporting Limit J = The analyte was positively identified; the quantitation is an estimation M = The result is estimated due to a matrix effect NA = Not Analyzed UJ = The analyte was not detected; hO\yever, the result is estimated due to discrepancies in meeting certain analyte-specific quality control criteria 'l!Is!illJ'¥~eiEI!K~EQ~~~'fQ~~YJf:A~DA'jfuTf"" MACTEC Project: 33S0092494 Prepared by: M. Barker 01126/10 Checked by: C. Crow 01127110 P:IProjeclsIAndrews AFB EnvironmentallFive-year reviewsI4.0_DeliverablesI4,I_ReponsIFinaIITablesl2,1 FT04-BY WELL 1-28-10 Page 9 of II Joint Base Andrews - First Five- Year Review November 2010 MACTEC Engineering and Consulting, Inc. Table 2.1 FT -04 Groundwater Monitoring Data Summary

• Site ill: FT04 FT04 FT04 FT04 FT04 FT04 FT04 FT-04 FT04 Location ID: MW9302-FT04 MW9302-FT04 MW9302-FT04 MW9302-FT04 MW9302-FT04 MW9302-FT04 MW9302-FT04 MW9302-FT04 MW9303-FT04 Sample ID: Regulatory MW9302FT4GW6057 MW9302FT4GW6224 MW9302FT4GW6301 MW9302FT04GW6376 MW9302FT04GW6525 MW9302FT04GW6600 MW9302FT04GW6702 MW9302FT04GW6740 MW9303FT4GW6058 Sample Date: Standard 06/15/2006 09112/2006 03128/2007 1012512007 05/22/2008 0911812008 03110/2009 9117/2009 06/13/2006 Sample Type: Sample Sample Sample Sample Sample Sample Sample Sample Sample

Metals - SW846 6010 6010B (Dissolved). m!!/L IArsenic I 0.01 NA 1 NA I NA I <0.01 I NA I NA I NA I NA I NA I IManganese I,Aijj59~\i NA I NA I NA I 0.0028 F I NA I NA I NA I NA I NA I

Metals - SW846 6010 6010B (Total). me/L - IArsenic I 0.01 NA I NA I <0.03 I NA I <0.01 I < 0.03 I < 0.03 I <0.03 I NA I IManganese k 0.159;t~l NA I NA I NA I NA I ., :,e.::·< .0.19j/.0'3;.I~J0,?~J 0139(;,~*'t.0'3Ti,tlm:.::,,·.·;,~;lh·.i',; ";;0B'I'K,: ',' .. ,'I0~t6 .' 'c,';it,;"r\ NA I

Metals - SW846 6020 (Dissolved). m!!IL IArsenic I 0.01 NA I NA I NA I NA I NA I NA I NA I NA I NA I IManganese 1~)O;T59~~i " NA I NA I NA I NA I NA I NA I NA I NA I NA I

Metals - SW846 6020 6020A (Total), me/L IArsenic I;'i, ,;WO·l?<.( 0.0024 F I 0.0035 F I NA I NA I NA I NA I NA I NA I 0.00051 B I IManganese . Efi'::;Oifs9_ V< -<"~ouf' M:;~"'] 0,12 I NA 1 NA J NA I NA I 'NA I NA I \~i~.t~;M7JiM.~1

Volatile Or!!anic ComDounds - SW846 8240 8260 8260B ue/L IBenzene I, •(S;m:': 0.17 F I <0.4 I < 0.4 I <0.4 I <0.4 I <0.4 I <0.4 I <0.4 1 2.1 I ICarbon tetrachloride 1"_'."'" ,.l'.k_ < I I < 1 I < I I < I I < 1 I < I I <1 I < 1 I 0.66 F I

Notes: Regulatory Standards are groundwater Site Remediation Goals • (SRGs) from Final Record ofDecision. FT04, (USAF, US EPA, and MDE,2005) mgIL = milligrams per liter ugIL = micrograms per liter Data reported prior to 2006 was not collected by MACTEC and cannot be verified Data collected after 2005 have been validated and checked by MACTEC < = Many laboratory detection limits reported prior to 2006 cannot be verified as to whether they are Reporting Limits or Method Detection Limits, therefore, to maintain the best possible consistent non-detect values, the Reporting Limit is' being represented for data collected after 2005

Data Flag Definitions:

B = Blank contamination: The analyte was found in an associated blank above 112 the Reporting Limit, as well as in the sample D = Sample result is a dilution F = Found: The analyte was positively identified but the associated concentration is an estimation above the Method Detection Limit and below the Reporting Limit J = The analyte was positively identified; the quantitation is an estimation M = The result is estimated due to a matrix effect NA = Not Analyzed UJ = The analyte was not detected; however. the result is estimated due to discrepancies in meeting certain analyte-specific quality control criteria :iiEsmT' EXCEEDSfR'E'GllllAfORY:ST:ANDARD''71i;~;; f","r MACTEC Project: 3350092494 A .• 'x-...... ,~.~ ~.'«"'d.•. ~~.. ..~...,...,;,,_ ..;:.._ .'<" .. _ ,'"-""" ...... ,,' ._~--";...'""".;;; • .r"'"'_".i_"':) Prepared by: M.Barker 01/26110 .' Checked by: C. Crow 01127110 P;IProjectslAndrews AFB EnvironmentailFive-year reviewsI4.0_DeliverablesI4.I_ReponsIFinaIITablesI2.1 FT04-BY WELL 1-28-10 Page 10 of II Joint Base Andrews - First Five- Year Review November 2010 MACTEC Engineering and Consulting, Inc. Table 2.1 FT-04 Groundwater Monitoring Data Summary

• Site ID: FT04 FT04 FT04 FT04 FT04 FT04 FT-04 FT04 Location ID: MW9303-FT04 MW9303-FT04 MW9303-FT04 . MW9303-FT04 MW9303-FT04 MW9303-FT04 MW9303-FT04 MW9304-FT04 Sample ID: Regulatory MW9303FT4GW6225 MW9303FT4GW6302 MW9303FT04GW6377 MW9303FT04GW6526 MW9303FT04GW660 I MW9303FT04GW6703 MW9303FT04GW674I MW9304FT4GW63 I I Sample Date: Standard 09/1212006 0312812007 10/25/2007 .05/2112008 09119/2008 03/09/2009 911712009 03/29/2007 Sample Type: Sample Sample Sample Sample Sample Sample Sample Sample

Notes: Regulatory Standards are groundwater Site Remediation Goals (SRGs) from Final Record ofDecision,FT04, (USAF, USEPA, and MDE,2005) mgIL = milligrams per liter ugIL = micrograms per liter. Data reported prior to 2006 was not collected by MACTEC and cannot be verified Data collected after 2005 have been validated and checked by MACTEC < = Many laboratory detection limits reported prior to 2006 cannot be verified as to whether they are Reporting Limits or Method Dete.ction Limits; therefore, to maintain the best possible consistent non-detect values, the Reporting Limit is being represented for data collected after 2005

Data Flag Definitions:

B = Blank contamination: The analyte was found in an associated blank above 112 the Reporting Limit. as well as in the sample D = Sample result is a dilution . F = Found: The analyte was positively identified but the associated concentration is an estimation above the Method Detection Limit and below the Reporting Limit J = The analyte was positively identified; the quantitation is an estimation M = The result is estimated due to a matrix effect NA = Not Analyzed UJ = The analyte was not detected: however, the result is estimated due to discrepancies in meeting certain analyte-specific quality control criteria ~~~.~Li;E~<:::EEDS:~~~.iATQ:Rji'~t:A~!>ARi)J:iIt{L·'; MACTEC Project: 3350092494 Prepared by: M. Barker 01126/10 Checked by: C. Crow 01127110 • P:IProjectslAndrews AFB Environmenta\IFive-year reviewsI4.0_DeliverablesI4.\_ReportsIFina\ITab\esl2.\ FT04-BY WELL \-28-\0 Page II of II Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Table 2.2 FT-04 Summary of Toxicity Value Updates

'. Chemical of Oral Referece Dose (RID) [mg/kg/dav) Inhalation Reference Dose (RID) [ml!;lkg/day) Oral Cancer Slope Factor (CSF) [mg/kg/dayri Inhalation Cancer Slope Factor (CSF) [mglkg/dayri Potential Concern Final RI Updated Final RI Updated Final RI Updated Final RI Updated (COPC) Value Source Value Source Value Source Value Source Value Source Value Source Value Source Value Source

Arsenic NA NA 4.3E-06 REL Benzo(a)pyrene 3.1 EPA 3.9 CALEPA bis(2-ethylhexyl)phthalate (chronic 0.014 NCEA 0.0085 CALEPA Cadmiwn (chronic) NA NA 5.7E-06 REL NA NA 6.3 IRIS Carbon tetrachloride 0.0007 IRIS 0.004 IRIS proposed 5.70E-04 ATSDR 2.90E-02 IRIS proposed 0.13 IRIS 0.07 IRIS proposed 0.053 IRIS 0.021 IRIS Proposed Chlorofonn (chronic) 1.40E-02 EPA 8.60E-02 REL Dibenzo( a.h)anthracene NA NA 3.9E+00 CALEPA Heptachlor 4.50E+00 IRIS 4.60E+00 IRIS Iron 0.3 EPA 0.7 PPRTV 4-Methylphenol NA NA 0.17 REL PCE 0.01 IRIS 0.004 IRIS proposed 0.14 EPA 0.077/0.005 A TSDRlIRlS proposed 5.40E-OI EPA 1.00E-OI IRIS proposed 2.0E-02 CALEPA 7.0E-02 IRIS proposed TCDD NA NA l.lOE-08 REL 1.50E+05 HEAST 1.30£+04 WHO TCE 6.00E-03 NCEA NNO.0004 NNIRlS proposed NA NA 0.0014 IRIS proposed I.IE-02 NCEA I.3E-02 12.0E-02 CALEPNIRlS proposed 6.0E-03 NCEA 7.0E-3/1.4E-2 CALEPNIRlS proposed Toluene 1.00E-0 I IRIS 0.08 IRIS 0.11 IRIS 1.4 IRIS Xylenes 0.02 IRIS 0.029 IRIS

Notes: IRIS - Integrated Risk Infonnation System (December 2009 IRIS Proposed - Integrated Risk Infonnation System (December 2009) - a Draft IRIS Assessment has been published for external peer reviev ATSDR - Agency for Toxic Substances and Disease Registry Minimwn Risk Level (MRL) (December 2008 CALEPA - Califonnia Environmental Protection Agency: slope factors (July 2009) and Reference Exposure Levels (RELs) (December 200~ NCEA - National Center for Environmental Assessment (NCEA) provisional dose-response valu• . PPRTV - Provisional Peer Reviewed Reference Toxicity Value HEAST - Health Effects Assessment Summary Tables 2008 (obtained from Oak Ridge National Library Regional Screening Levels for Chemical Contaminants at Superfund Site! PPRTV - Provisional Peer Reviewed Reference Toxicity Valu! WHO: World Health Organization, May 200S

MACTEC Project: 3350092494 Prepared by: [(ASK 01/2112010 • P:\ProjectslAndrews AFB EnvITonmental\Five-year reviewsl4.0_ DeliverablesI4.1_Reports\FinaIlT ablesl2.2 FT-04 DR summary Page I of 1 Checked by: JHP 0112112010 Joint Base Andrews - First Five-Year Review November2010 MACTEC Engineering and Consulting. inc.

Table 3.1 • ST-I0 Groundwater Monitoring Requirements Sampling Event Target Parameters Sample Locations 3-month and 6-month VOCs, EPWVPH, total/dissolved All wells except ST 1OMW -07 post-ORC® injection arsenic, anions, alkalinity, methane, and STlOMW-ll ethane, ethene, field & geochemical parameters, PLFA 12-month post-ORC® EPHNPH, total/dissolved arsenic, STlOMW-Ol (background) injection anions, alkalinity, methane, ethane, through STl OMW-04 (i.e., ethene, field & geochemical parameters Central Plume) I8-month post-ORC® VOCs, EPWVPH, total/dissolved All wells except STl OMW-07 injection arsenic, anions, alkalinity, methane, and STlOMW-ll ethane, ethene, field & geochemical parameters, PLF A 24-month post-ORC® EPWVPH, total/dissolved arsenic, .STl OMW-01 (background) injection anions, alkalinity, methane, ethane, through STl OMW-04 (i.e., ethene, field & geochemical parameters Central Plume) 36-month post-ORC® VOCs, EPHNPH, total/dissolved All wells except STIOMW-07 injection arsenic, anions, alkalinity, methane, and STlOMW-11 ethane, ethene, field & geochemical parameters, PLF A 48-rrionth post-ORC® VOCs, EPWVPH, total/dissolved All wells except STl OMW-07 injection arsenic, anions, alkalinity, methane, and STlOMW-11 ethane, ethene, field & geochemical parameters, PLFA 6O-month post-ORC® VOCs, EPHNPH, total/dissolved All wells except STlOMW-07 injection (5 year) arsenic, anions, alkalinity, methane, and STlOMW-ll ethane, ethene, field & geochemical parameters, PLF A Biennial ~vents (years EPHIVPH, total/dissolved arsenic, STIOMW-Ol (background) 7,9,11,13,15,17,19, anions, alkalinity, methane, ethane, through STl OMW-04 (i.e., 21,23,25) ethene, field & geochemical2arameters Central Plume) Notes: Table based on ROD Subsection 2.9.2.1, ROD Table 4-1, and FFS Table 4.2 Analytical methods: TCL VOCs (CLP Method OLM03.2) Anions (Method SW9056) VPHlEPH (Massachusetts VPHlEPH method) Arsenic, total and dissolved (Method 6010/602017000) Methane, ethane, and ethene (SW-846 Method RSK 175) PLF A Microbial Insights Alkalinity (EPA method 310.1) Field measurements such as dissolved oxygen, ORP, pH, ferrous iron would be analyzed.

MACTEC Project: 3350092494 Prepared by: SWR 01111/2010 Checked by: JEB 02115/2010 J of 1 • P:\Projects\Andrews AFB EnvironmentaJ\Five·year reviewsI4.0_DeliverabJesI4.I_Reports\FinaJITabJesI3.1 ST·W OW sample.docx 3350092494 Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Table 3.2 ST-lO Groundwater Monitoring Data Summary

• Arsenic Arsenic Sample Sample Benzene Naphthalene Dissolved Total Location ID Date

MWOI-STIO 3/27/2001 Pre-Treatmt <0.4 <0.030 MWOI-STIO 4/16/2002 Pre-Treatmt <0.4 NA NA MWOI-STIO 9/4/2003 Pre-Treatmt <0,18 <5 NA <0,030 MWOI-STIO 9/9/2004 Baseline <0,14 <0,13 0.00029 F 0.00035 F MWOI-STIO 1/25/2005 3 month <0,14 <0,13 NA NA MWOI-STIO 4/18/2005 6 month <0,14 <0,13 NA NA MWOI-STIO 10/3112005 12 month NA NA <0,0020 <0.0020 MWOI-STIO 612112006 18 month <5,0 ND 0,00086 F 0.00045 F MWOI-STIO 9113/2006 24 month NA NA 0.00025 F 0,00067 F MWOI-STIO 10125/2007 36 month <0,0001 <11.0 <0.003 <0,003 MWOI-STIO 9/18/2008 48 month <0.02 <0.5 0.00026 F 0,00059 F MWOI-STIO 9/15/2009 60 month < 0,019 < 0.44 0,00028 F 0.00027 F MWOI- 9/15/2009 D 60 month < 0.019 < 0.44 0.00024 F MW02-STI0 3/27/2001 Pre-Treatmt 0.49 NA NA MW02-STIO 4/16/2002 Pre-Treatmt 0,53 NA MW02-STI0 9/3/2003 Pre-Treatmt 0,55 J MW02-STIO 1125/2005 3 month NA MW02-STI0 4118/2005 6 month NA MW02-STI0 11/112005 12 month NA MW02-STI0 6/20/2006 18 month <5.0 MW02-STIO 9/13/2006 24 month NA NA MW02-STIO 10/24/2007 36 month <0.0001 UJ ~JQ&lS.. MW04-STIO 1111/2005 12 month NA NA NA MW04-STIO 6121/2006 18 month <5,0 ND MW04-STIO 6/21/2006 D 18 month <5,0 ND MW04-STIO 9113/2006 24 month NA NA MW04-STIO 9/13/2006 D 24 month NA NA MW04-STIO 10/~5/2007 36 month <0,001 <11.0 MW04-STIO 9/16/2008 48 month 0.9 <0.5 MW04-STIO 9/16/2009 60 month ,0 0.77 F

Page I of3 MACTEC Project: 3350092494 • Prepared by: M, Barker 01/111201 0 P:lProjects\Andrews AFB EnvironmentallFive-year reviewsI4.0_DeliverablesI4, I_Repot1slFinaIlTables\3.2 STIO COC by well Checked by: SWR 01112/2010

Joint BQse Andrews - First Five-Year Review' November 2010 MACTEC Engineering and Consulting, fnc. Table 3.2 ST-IO Groundwater Monitoring Data Summary

• Arsenic Arsenic Sample Sample Benzene Naphthalene Dissolved Total Location ID Date Timing uglL uglL mg!l mglL SRG 5 18 0.01 0.01 MWIS-STlO 10/25/2004 Baseline <0.14 12 0.0016 0.0049 MWI5-STI0 1127/2005 3 month <0.14 2.2 NA NA MWIS-STIO 4/18/2005 6 month 0.14 0.16 J NA NA MWI5-STlO 6/2012006 18 month <5.0 ND 0.0017 F 0.0019 F MWIS-STlO 10/25/2007 36 month <0.001 <11.0 0.0039 F 0.0036 F MWIS-STlO 9/18/2008 48 month <0.02 <0.5 0.00058 F 0.0017 F MWI5-STIO 9117/2009 60 month < 0.019 < 0.44 0.0019 F 0.0021 F MWI6-STIO 10/22/2004 Baseline <0.14 <0.13 0.00047 J 0.00039 J MWI6-STlO 1127/2005 3 month <0.14 <0.13 NA NA MWI6-STI0 4/20/2005 6 month <0.14 <0.13 NA NA MWI6-STlO 6/21/2006 18 month <5.0 ND 0.00035 F 0.00058 F MWI6-STlO 10/2512007 36 month <0.001 <11.0 <0.003 <0.003 MWI6-STlO 9/16/2008 48 month <0.02 <0.5 0.0016 F 0.0017 F MWI6-STlO 9/1612009 60 month <0.019 < 0.44 0.0071 0.0066

Notes: mg/L = milligrams per liter ugIL = micrograms per liter Naphthalene was identified by Mass Method VPH.analysis for the October 2007 samples Validity of data collected prior to OctoberlNovember 2005 by other consultants could not be verified by MACTEC Data collected after 2005 has been validated and checked by MACTEC

. Data Flags: • NA,= Not Analyzed, Not Reported, orNot Available ND = Not Detected as a Tentatively Identified Compound (TIC), for compounds that are not target analytes of Method SOM 01.1 < = Less than the Reporting Detection Limit for data collected through 2006. Less than the Method Detection Limit for data collected after 2006 at the request ofERP. F1= The analtye was positively identified, but the associated numerical value is below the Reporting Limit J = The analyte was positively identified, the quantitation is an estimation M = A matrix effect was present N = Tentatively identified; blank recovery not within control limits mrghli11ft~ili:~W{fel'E'~@~'"R.9D;~~Gll1t:·. -"I,. 5~,"':

Page 3 of 3 MACTEC Project: 3350092494 • Prepared by: M. Barker 01/1112010. P:lProjects\Andrews AFB EnvironmentallFive-yearreviewsI4.0_DeliverablesI4.I_ReponslFinaIITables\3.2 STIO COC by well Checked by: SWR 01/12/2010 Joint Base Andrews - First Five- rear Review November 20 I 0 MACTEC Engineering and Consulting, Inc. Table 3.3 • ST-IO Summary of Toxicity Value Updates Chemical of Oral Referece Dose (RID) (mglkg/dav) Inhalation Reference Dose (RID) [mglkglday) Oral Cancer Slope Factor (CSF) (mwkWdayr1 Inhalation Cancer Slope Factor (CSF) (mglkgldayr1 Potential Concern Final RI Updated Final RI Updated Final RI Updated Final RI Updated (COPC) Value Source Value Source Value Source Value Source Value Source Value Source Value Source Value Source

Chlorofonn 0.014 NCEA 0.OS6 CALEPA JOE-OI IRIS S.IE-02 rRlS MTBE 4.0E-03 EPA l.SE-03 CALEPA TCE 0.006 NCEA 0.0004 rRlS proposed NA 0.0014 IRIS proposed l.lE-02 NCEA 1.3E-02 12.0E-02 CALEPAlIRIS proposed 6.0E-03 NCEA 1.4E-02/4E-OI CALEPAIrRlS proposed Dibenzofuran 0.002 NCEA withdrawn Pentachlorophenol 0.Q3 IRIS 0.005 IRIS proposed 1.2E-OI HEAST 4.0E-OI IRIS proposed 1,4-Dichlorobenzene 0.Q3 NCEA 0.07 ATSDR 2.4E-02 IRIS 5.4E-03 CAL EPA 2.2E-02 HEAST 3.9E-02 CALEPA cis( 1,2-dichloroethene) 0.01 PPRTV 0.006 IRIS proposed 1,2,4-Trimethylbenzene 0.05 PPRTV withdrawri

Notes: IRIS - Integrated Risk Infonnation System (December 2009) IRIS Proposed - Integrated Risk Infonnation System (December 2009) - a Draft IRIS Assessment has been published for external peer review. ATSDR - Agency for Toxic Substances and Disease Registry Minimum Risk Level (MRL) (December 200S) CALEPA - Califonnia Environmental Protection Agency: slope factors (July 2009) and Reference Exposure Levels (RELs) (December 200S) NCEA - National Center for Environmental Assessment (NCEA) provisional dose-response value PPRTV - Provisional Peer Reviewed Reference Toxicity Value HEAST - Health Effects Assessment Summary Tables •

MACTEC Project: 3350092494 Prepared by: KASK 01/05/2010 • P:\ProjeclsIAndrews AFB EnvironrnentaJIFive-year reviewsl4.0 _DeliverablesI4.I_ReportsIFinaIITablesI3.3 ST-IO DR sununary Page I of 1 Checked by: JHP 01/05/2010 Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineerillg and Consulting. Inc.

Table 4.1 ST-14 Groundwater Monitoring Data Summary

ORP DO TCE Benzene m,p-Xylene : o-Xylene Toluene • Location Sample Date (mY) (mglL) IpH (s.u.) (JlgIL) CT (JlgIL) VC (JlglL) (JlglL) (JlglL) (JlgIl) (JlglL) SRG - .­ - .­ 5 5 2 5 500 * 500 * 300 MWOI 1/1/91 7 12 NO MWOI 1/1/92 4 9 NO MWOI 1/1/99 16 9 NO MWOI 111100 19 9.5 NO MWOI 3/1/2006 459.3 1.28 4.42 75.1 7.21 I U 0.4 U 2 U I U I U MWOI 11/212007 464 1.6 4.48 MWOI 41712008 275 1.14 4.05 21.4 4.61 I U 0.4 U 2 U I U I U MWOI 7111/2008 401 1.73 4.23 29.3 6.1 I U o U 2 U I U I U MWOI 101712008 420 0 4.2 26.9 L 4.63 L I UL 0.4 UL 2 UL I UL I UL MWOI 1/12/2009 384 0.52 3.92 23.3 5.44 I U 0.4 U 2 U IU I U MWOI 4/15/2009 397 0.98 3.94 24.6 5.44 I U 0.4 U 2 U I U I U MWOI 712812009 391 0 4.28 34.6 6.42 I U 0.4 U 2 U I U I U MWOI 1011612009 394 2.87 4.14 30.3 5.84 IU 0.4 U 2 U I U IU MW02 1/1/91 NO NO 280 MW02 1/1/92 NO NO 50 MW02 1/1/96 NO NO NO MW02 1/1/99 12 NO 360 MW02 111100 17 NO 380 MW02 311/2006 401.8 3.92 4.3 4.44 1 U I U 22.3 4.96 I U 0.283 J MW02 11/2/2007 52 . 0.36 5.46 MW02 41712008 214 4.98 4.12 0.38 I ) I U I U 0.352 J 2 U I U I U MW02 7/1112008 134 1.58 5.39 23.6 I U I U 120 4.21 1.1 2.84 MW02 101712008 36 0 5.8i 39.4 I U I U 206 J 4.1 2.82 6.35 MW02 1/13/2009 181 3.5 5.29 12.3 I U I U 64.2 1.13 J IU 0.865 J MW02 4/16/2009 236 5.44 4.11 I U I U IU 0.4 U 2 U IU IU MW02 7/22/2009 95 0 5.3 30.9 I U IU 165 17.3 5.66 9.13 MW02 10/16/2009 -27 . 2.27 5.66 32.8 2 U 2 U 204 1.46 ) 5.5 12 MW03 1/1/91 81 NO 3400 • MW03 1/1/92 49 NO 3000 MW03 1/1/96 157 NO 1734 MW03 1/1/99 47 NO 1500 MW03 111100 37 1.3 1100 MW03 2128/2006 144:9 0.72 4.59 61.6 ) IUJ I UJ 154 ) 2.41 ) 1.08 ) 4.64 ) MW03 10/2412007 309 0.05 4 MW03 11/1/07 65.7 IU I U 86.3 2 U 0.395 ) 2.55 MW03 4/4/2008 194 0.04 4.1 61.9 IU I U 72.2 0.596 ) 0.408 ) 3 MW03 7/9/2008 230 2.2 4.42 59.9 0.903 ) I U 69.8 1.84 0.841 2.21 MW03 10/1/2008 272 0 4.22 74.1 0.393 ) I U 60.6 3.3 1.57 6.56 MW03 1/6/2009 . 327 0 4.01 64.7 IU I U 60.7 0.608 ) 0.349) 2.2 MW03 4/912009 217 0 4.01 63.1 0.33 ) I U 46.6 2 U I U 1.69 MW03 7/2412009 210 '0.7 4.35 48.8 0.346 ) I U 45.5 2 U I U 1.28 MW03 10115/2009 276 0 4.46 55.8 IU 1 U 37.8 2U I U 1.41 MW03-3471 3/1/2006 70.7 0.04 5.58 I U I U I U 14.8 2 U 1 U IU MW03-3471 4/412008 19.1 0.4 5.57 IU I U 1 U 42.5 0.938 J 0.61 I ) 0.35 J MW03-3471 711112008 -30 1.37 5.81 I U I U I U 36.2 2 U I U I U MW03~3471 101712008 -68 0 5.76 0.253 1. 1 U 1 U 49.3 0.544 ) 1 U I U MW03-3471 1/1312009 -23 0 5.47 I U 1 U I U 37.6 2 U 1 U I U MW03-3471 4113/2009 -29 3.95 5.54 I U 1 U 1 U 47.7 0.806 ) 1 U I U MW03-3471 7/22/2009 -51 6.85 6.09 1 U 1 U 1 U 21.7 2 U I U 0.27 J MW03-347I. 10/13/2009 -64 0 5.89 I U I U I U 54 2 U I U IU MW04 111191 53 NO 1700 MW04 1/1192 NO NO 3500 MW04 1/1/96 94.7 NO 1547 MW04 1/1199 NO NO 3800 MW04 111100 160 NO 3700 MW04 2/28/2006 -102.1 0.81 6.28 63.6 ) 1 UJ I U) 837 J 2510 ) 960 ) 4070 J

Page I of8 MACTEC Project: 3350092494 • Prepared by: AECOM 12/17/2010 4.0_Oeliverables\4. I _Reports\Oraft\Tables\4.1 STI4 by well Checked by: SWR 0112512010 Joint Base Andrews - First Five-Year Review November 2010 MA CTEC Ellgilleerillg alld Consultillg. Illc. Table 4.1 ST-14 Groundwater Monitoring Data Summary

ORP DO 'TCE Benzene m,p-Xylene o-Xylene Toluene • Location Saml!le Date (mY) (mwL) pH (s.u.) ("giL) CT ("giL) VC ("WL) ("giL) ("WL) ("WL) ("gil) SRG - - - - 5 5 2 5 500 * 500 * 300 MW04 1012212007 -89 0.04 6.38 MW04 111108 32.2 IU J U 855 2120 860 3010 MW04 4/4/2008 -13.1 0.04 5.86 25.7 25 U 25 U 876 1830 . 756 .2600 MW04 7/9/2008 -76 1.37 6.02 28.5 25 U 25 U 655 1320 552 2200 MW04 10/312008 -74 0 6.31 21.9 IU IU 648 J 1230 J 753 J 1200 J MW04 116/2009 -42 0.6 5.76 17.8 J 20 U 20 U 502 1540 670 1840 MW04 4/8/2009 -110 0 5.87 28 10 U 10 U 642 2020 795 2540 MW04 7/30/2009 -107 0.71 5.94 97.8 5 U 5 U 441 1630 651 1930 MW04 10/1512009 -119 0 6.75 187 20 U 20 U 428 1630 629 1870 MW05 111191 24 26 330 MW05 111192 55 33 330 MW05 111/96 34.5 NO 420 MW05 111/99 64 18 150 MW05 111100 14 4.2 39 MW05 2/2812006 21.16 1.64 5.72 11.3 1.29 IU 45.1 2004 7.62 35.7 MW05 10122/2007 271 8.08 6.67 ivlW05 1/1108 21.8 2.91 I U 59.5 38 15.5 59.2 MW05 3128/2008 135 2.27 5.62 14.1 4.43 IU 32.8 18.3 7.77 37.9 MW05 7/11/2008 62 4.69 5.87 20 6.09 I U 29.6 41 14.5 55.1 MW05 10/6/2008 80 9.35 6.19 49.9 9.35 IU 22.8 26.9 9.81 25.7 MW05 116/2009 77 8.06 5.35 49.5 10.7 I U 54.9 44.4 . 16;9 43.5 MW05 4/1012009 63 4.35 5.64 23.1 4.8 I U 32.5 26.4 9.97 23.4 MW05 7/2712009 -26 4.88 5.99 32.5 5.49 IU 33.7 31.5 11.9 27 MW05 10/15/2009 69 1.87 5.99 27.7 3.6 IU 34.8 43.2 15 38.5 MW06 1/1191 68 42 NO MW06 111/92 10 NO NO MW06 1!1/99 7.7 2.4 0~2 MW06 111100 4.4 NO NO • MW06 2128/2006 395.1 7.89 5.99 2.88 I U IU 0.4 U 2 U I U I U MW06 10/25/2007 280 5.71 4.94 MW06 41712008 195.3 0.63 5.93 3.04 I U I U 0.4 U 2 U IU I U MW06 7/9/2008 215 3.83 6.29 5.33 I U I U 0.162 J 1.73 J 0.606 J 1.59 MW06 10/6/2008 171 1.3 5.17 5.33 I U I U 0.4 U 2 U I U I U MW06 1/612009 237 1.24 5.18 12.2 0.72 J I U 0.4 U 2 U I U I U MW06 4/8/2009 192 6.4 5.51 4.63 I U I U 0.4 U 2 U I U I U MW06 712812009 146 2.87 4.86 2.05 IU I U 0.4 U 2 U I U I U MW06 10115/2009 183 1.46 5.25 1.72 IU IU 0.4 U 2 U IU I U MW07 111/91 15 4 .2 MW07 111/92 61 18 4 MW07 111/96 45.3 NO, NO MW07 1/1/99 800 1.8 4.8 MW07 111100 240 0.5 1.4 MW07 3/1/2006 300.6 2.61 4.92 71.3 2.46 I U 0.283 J 2 U 1 U I U MW07 10/3112007 344 0.17 4.85 MW07 Jan-08 74.5 3.27 1 U 0.51 2 U I U I U MW07 41712008 383.3 0.12 4.39 62.1 1.85 I U 0.319 J 2 U I U IU MW07 7110/2008 211 3.09 5.63 207 0.577 J I U 0.161 J 2 U I U IU MW07 10/6/2008 199 8.79 5.65 631 J IU I U 0.4 U 2 U I U IU . MW07 116/2009 190 1.5 5.35 825 5 U 5 U 2 U 10 U 5 U 5 U MW07 41712009 207 6.06 5.52 780 1.68 J 5 U 2 U 10 U 5 U 5 U MW07 7/3012009 158 0 5.22 102 IU '1 U 0.4 U 2 U IU I U MW07 10/14/2009 137 7.48 6.06 36.2 IU IU 0.4 U 2 U IU IU MW08 111/91 54 NO NO MW08 1/1/92 69 II NO MW08 111/99 170 NO NO

MW08 111100 23 NO ND .'

Page 2 of8 MACTEC Project: 3350092494 • Prepared by: AECOM 12/17/2010 4.0_0eliverables\4.I_Reports\Oraft\Tables\4.1 STI4 by well Che~ked by: SWR 01/25/2010 Join! Base Andrews - First Five- Year Review November 2010 MA CTEC Engineering and Conslliting, Inc. Table 4.1 ST-14 Groundwat~r Monitoring Data Summary

ORP DO TCE Benzene m,p-Xylene o-Xylene Toluene • Location Sample Date (my) (mglL) pH (s.u.) ("gIL) CT ("gIL) VC ("giL) ("gIL) ("giL) ("giL) ("gIL) SRG - - - - 5 5 2 5 500 * 500 * .300 MW08 2/28/2006 106.1 2.81 5.84 "187 0.298 J I U 0.143 J 2 U IU I U MW08 10/3112007 180 5.57 6.39 MW08 4/4/2008 129.3 8.4 6.8 8.04 I U I U 0.4 U 2 U I U I U MW08 7/912008 151 3.42 6.86 27.4 I U I U o U 2U I U I U MW08 10/3/2008 168 1.23 5.38 44.5 I U I U 0.4 U 2 U I U I U MW08 116/2009 190 9.25 6.59 3.37 I U I U 0.4 U 2 U I U I U MW08 41712009 311 9.03 6.67 I U I U IU 0.4 U 2 U I U I U MW08 7/24/2009 96 4.36 6.29 2.02 I U I U 0.4 U 2 U I U I U MW08 10/16/2009 107 4.38 6.4 2.57 I U IU 0.4 U 2 U I U I U MW09 111/91 190 NO NO MW09 111192 200 NO NO MW09 111/99 12 NO NO MW09 1/1100 0.6 NO ND MW09 3/2/2006 249.2 5 4.19 1.19 I U I U 0.4 U 2 U I U I U MW09 1111/2007 421 4.01 4.42 MW09 1122/2008 196.8 7.02 4.59 0.717 J I U I U O.4·U 2 U I U I U MW09 4/8/2008 261.9 0.88 5.35 0.253 J I U I U 0.4 U 2 U I U I U MW09 7/10/2008 345 3.56 4.56 IU I U I U o U 2 U I U I U MW09 101712008 397 10.42 3.38 0.626 L I UL I UL 0.4 UL 2 U I UL I UL MW09 11912009 262 5.5 5.05 I U 1 U I U 0.4 U 2 U IU I U MWP9 4113/2009 350 6.62 4.07 I U I U I U 0.4 U 2 U I U I U MW09 712812009 178 2.67 4.23 I U IV I U 0.4 U 2 U 1 U I U MW09 10/16/2009 355 1.53 4.47 1 U IU I U 0.4 U 2 U 1 U I U MWIO 111192 42 NO 2200 MWIO 1/1199 50 NO 4700 MWIO 111100 6.8 NO 20000 MWIO 3/112006 .24.3 0.23 5.68 200 U 200 U 200 U 6030 8880 3970 37800 MWIO 11/9/2007 2 22.57 10.59 • MWIO 4/4/2008 .94 5.87 9.71 2.5 U 2.5 U 2.5 U 1010 . 924 810 4850. MWIO 7/9/2008 -107 0.44 7.63 10 U 10 U 10 U 4360 7090 3510 25800 MWIO 10/3/2008 -132 6.33 8.02 100 U 100 U 100 U 908 2760 1530 5920 MWIO 11712009 41 3.81 7.73 5 U 5 U 5 U 107 436 281 611 MWIO 4113/2009 -113 0 5.92 2.5 J 5 U 5 U 1670 1360 991 9760 MWIO 7/29/2009 -40 10.96 50 U 50 U 50 U 2940 5750 2860 20700 MWIO 10/15/2009 14 >19:99 )(').97 5 U 5 U 5 U 211 293 203 792 MWII 1/1/92 1100 NO NO MWII 1/1/99 1500 I 0.4 MWII 111100 1400 0.9 0.3 MWII 3/112006 320.4 1.49 4.46 624 0.505 J I U 0.163 J 2 U I U IU MWII 6128/2006 42.6 1.9 5.14 545 I U I U 0.149 J 2 U I U 0.287 J MWII 8/3012006 -8.8 0.31 5.1 209 I U I U 0.4 U 2 U I U I U MWII 101912006 5.37 0.75 4.96 378 IU I U 0.4 U 2 U 1 U I U MWII 10/23/2007 -53 -0.04 5.43 32.1 5 U 5 U 2 U 10 U 5 U 5 U MWII 1/2212008 -35 0.16 5.28 145 IU 1.14 0.237 J 2 U IU 0.266 J MWII 3/26/2008 1.9 0.3 4.89 67.9 2 U 0.71 J 0.439 J 4 U 2 U 2 U MWII 6/19/2008 47 0 6.46 77.5 2 U 1.14J 0.663 J 4 U 2 U 2 U MWII 10/612008 -45 2.37 6.76 14.8 J IR 3.07 J 0.4 R 2 U IU 0.306 J MWII 1/12/2009 -119 0 9.26 9.81 IU 4.92 0.355 J 2 U IU 0.288 J MWII' 41712009 -106 0.38 6.48 4.3 J 10 U 10 U 4 U 20 U 10 U 10 U MWll 7/2812009 -187 0.65 6.25 1.2 IU 2.68 0.549 2 U I U IU MWII 10/16/2009 -177 0 7.39 0.625 J IU 16.9 0.645 2 U IU 0.362 J MWI2 111/92 5800 NO 7 MWI2 1/1/99 2500 NO NO MWI2 111100 450 NO 0.5 MWI2 3/2/2006 310.6 5.46 4.76 1180 IU IU 0.202 J 2 U I U IU MWI2' 10/22/2007 306 2.96 5.12

Page 3 of 8 MACTEC Project: 3350092494 • Prepared by: AECOM 12117/2010 4.0_0eliverables\4.I_Reports\Oraft\Tables\4.1 STI4 by well Checked by: SWR 01/2512010 Joillt Base Alldre»'s - First Five-Year Review November 2010 MACTEC Engineerillg and COllsulting. fllc . Table 4.1 ST-14 Groundwater Monitoring Data Summary

ORP DO TCE Benzene m,p-Xylene o-Xylene Toluene • Location Sample Date (mV) (mg/L) IpH (s.u.) (jl21L) CT (llglL) VC (!lglL) (!l21L) (!lglL) (!lglL) ("glL) SRG - - .­ - 5 5 2 5 500 * 500 * 300 MWI2 1122/2008 156 2.84 5.16 505 IV IV 0.4 V 2 V I V I V MWI2 3/25/2008 221.6 1.63 5.38 505 5 V 5 V 2 V IOV 5 V 5 V MWI2 6/1112008 97 0.77 5.38 457 2.5 V 2.5 V IV 5 V 2.5 V 2.5 V MWI2 10/312008 92 3.74 6.26 82.9 5 V 5 V 2 V 10 V 5 V 5 V MWI2 118/2009 63 2.34 5.2 237 I V I V 0.4 V 2 V I V I V MWI2 4114/2009 66 0.76 6 186 I V I V 0.4 V 2 V I V I V MWI2 7/29/2009 181 0.28 4.93 233 IV I V 0.4 V 2 V I V I V MWI2 10/1312009 125 3.53 5.38 182 IV I V 0.4 V 2 V I V I V MWI3 111/92 240 NO NO MWI3 1/1/99 1100 NO NO MWI3 1/1100 890 NO NO MW13 2/28/2006 301.9 2.76 4.55 687 IV I V 0.4 V 2 V I V I V MWI3 6/28/2006 83.67 0.11 5.31 275 IV I V 0.4 V 2 V I V IV MW13 8/30/2006 -152.6 1.61 5.7 560 IV I V 0.4 V 2 V I V IV MW13 1011112006 -118.1 2.46 5.82 232 2 V 2 V 0.8 V 4 V 2 V 2 V MW13 10/23/2007) -60 0 6.23 1.15 J 2 V 6.79 0.8 V 4 V 2 V 2 V MWI3 1/23/2008 -77 0.11 6.32 0.411 J I V 3.15 0.345 J 2 V I V I V MWI3 3/24/2008 -70 0.02 6.26 0.512 J I V 2.23 0.216 J 2 V I V I V MW13 . 6/1112008 -84.1 0.46 6.12 1.06. IV 1.73 0.282 J 2 V I V I V MWI3 10/312008 -144 0 7.21 0.382 J I V 1.9 0.233 J 2 V IV I V MWI3 1/7/2009 -131 0 9.69 0.304 J I V 0.964 J 0.251 J 2 V IV I V MWI3 4/912009 -108 1.56 6.36 0.277 J I V 0.679 J 0.229 J 2 U I V I V MWI3 7/22/2009 -158 3.52 6.58 0.333 J I V 0.984 J 0.225 J 2 V I V I V MWI3 10/1312009 -202 0 6.87 0.447 J I V 0.922 J 0.169 J 2 V I V I V MWI4 111/92 3 NO 57 MWI5 1/1/00 370 NO I MWI5 2/2812006 248.4 5.13 4.91 241 I V I V 0.4 V 2 V IV I V MWI5 6/28/2006 4.57 0.23 5.34 233 1 V I V 0.4 V 2 V I V I V • MWI5 8/30/2006 -79.4 0.48 5.45 243 1 V I V 0.4 V 2 V IV I V MWI5 10/10/2006 -105.07 0.42 5.68 265 1 V IV 0.4 V 2 V IV I V MWI5 10/23/2007 -95 0.03 6.45 3 2 V 2 V 0.8 V 4V 2 V 2 V MWI5 1123/2008 -110 . 0.85 6.6 0.814 J I V 0.416 J 0.4 V 2 V I V I V MWI5 3/24/2008 -138 0 6.72 0.52 J I V 0.513 J 0.4 V 2 V 1 V 1 V MWI5 6/18/2008 -140 0 7.12 0.411 J I V 0.587 J 0.4 V 2 V 1 V 1 V MWI5 10/3/2008 -179 0 7.25 0.422 J I V 1 V 3.13 2 V I V I V MWI5 1/7/2009 -164 0 10.13 0.421 J I V IV 0.384 J 2 V IV I V MWI5 4/9/2009 -128 0.51 6.86 0.351 J I V IV 0.4 V 2 V I V I V MWI5 7123/2009 -202 0.07 7.06 0.329 J I V 0.359 J 0.272 J .2 V I V I V MWI5 10/1312009 -166 0 7.4 0.462 J IV 0.463 J 0.368 J 2 V I V I V MWI6 111100 69 NO 1.3 MWI6 3/1/2006 509.3 0.76 4.66 64.8 I V 0.432 J 0.531 2 V IV I V MWI6 111812007 390 0.32 3.62 MWI6 1/1108 27.5 I V IV 0.321 J 2 V I V 1 V MWI6 3/26/2008 340.6 0.79 4.45 88.3 I V 0.674 J 0.804 2 V I V 1 V MWI6 6/16/2008 160 0.08 4.92 86.5 I V 0.743 J 0.839 2 V I V I V MWI6 10/3/2008 339 0 4.27 68.8 I V 0.887 J 0.611 2 V I V I V MWI6 1/9/2009 288 0 3.38 59.7 IV 0.388 J 0.42 2 V I V I'V MWI6 4/7/2009 277 0 4.18 75.4 I V 0.318 J 0.447 2 V I V I V MWI6 7/23/2009 210 0.26 4.58 67.3 IV 0.722 J 0.746 2 V IV I V MWI6 10/12/2009 313 0 4.68 65.2 IV 0.624 J 0.453 2 V IV I V MWI7 111100 1600 NO 27 MWI7 3/2/2006 249.7 0.59 4.89 1240 I V 2.25 J 7.74 1.33 J 0.294 J 0.26 J \ MWI7 1116/2007 206.7 0.96 4.78 MWI7 1/1/08 1380 I V 2.8 7.29 1.33 J 0.256 J IV MWI7 3/27/2008 33 0.13 5.59 1150 10 V 10 V 5.91 20 V 10 V 10 V MWI7 6/10/2008 0.8 0.35 5.87 402 10 V 10 V 5.57 20 V 10 V 10 V

Page 4 of8 MACTEC Project: 3350092494 • l Prepared by: AECOM 12/17/2010 4.0_Oeliverables\4.1_ Reports\Oraft\Tables\4.1 STl4 by well Checked by: SWR 01/25/2010 Joilll Base Andrews - First Five-Year Review November 2010 MACTEC Engineering alld Consultillg. Inc. Table 4.1 ST-14 Groundwater Monitoring Data Summary

ORP DO TCE Benzene m,p-Xylene o-Xylene, Toluene • Location Sample Date (mV) (mWl) IpH (s.u.) ("giL) CT (!1g1L) VC (J.lWl) (J.lglL) ("giL) ("giL) ("giL) SRG - - - - 5 5 2 5 500 * 500 * 300 MWI7 9/30/2008 -126 0 6.49 IOU 10 U 10 U 124 20 U 10 U 33.3 MWI7 1/812009 -119 0 9.16 5 U 5 U 1.66 J 5.52 10 U 5 U 5 U MWI7 4/14/2009 -131 0 6.09 2.68 I U 3.26 5.65 2 U 0.387 J IU MWI7 7/24/2009 -197 0.Q7 6.6 10 U 10 U 2.7 J 5.5 20 U 10 U 10 U MWI7 10/1312009 -196 0.61 6.8 20 U 20 U 20 U 8 U 40 U 20U 20 U MWI8 111100 NO NO NO MWI8 3/2/2006 516.3 1.59 4.62 IU I U I U 0.4 U 2 U IU I U MWI8 1116/2007 234.2 0.43 4.71 MWI8 3/27/2008 279.4 1.09 4.74 I U I U I U 0.4 U 2 U I U I U MWI8 7/912008 291 1.54 4.81 I U I U I U o U 2 U I U I U MWI8 9/30/2008 303 0 2.48 IU I U I U 0.4 U 2 U I U I U MWI9 111/00 390 ND I MWI9 3/2/2006 394.1 5.94 4.55 2610 0.47 J I U 0.567 2 U IU I U MWI9 10/22/2007 351 0.61 4.97 MWI9 1/22/2008 -29.8 5.61 5.03 2580 0.383 J I U 0.645 2 U IU I U MWI9 3/2512008 -38 0 5.1 1880 10 U 10 U 4 U 20 U IOU 10 U MWI9 6/11/2008 -42 0 5.85 1960 10 U 10 U 4 U 20 U 10 U 10 U MWI9 10/3/2008 -49 5.06 5.96 1170 20 U 20 U 8 U 40 U 20 U 20 U MWI9 118/2009 -92 0 5.92 412 10 U 10 U 4 U 20 U IOU 10 U MWI9 4/1412009 -136 0.45 6.15 8.25 J 10 U 10 U 4 U 20 U 10 U 10 U MWI9 7/29/2009 -142 0 6.4 2.93 J 5 U 5 U 0.905 J 10 U 5 U 5 U MWI9 10/1312009 -128 0 6.74 3.38 J IOU 10 U 4 U 20 U 10 U 10 U MW20 111100 NO NO 9.9 MW20 3/812006 377.9 2.49 4.36 I U IU I U 0.4 U 2 U I U I U MW20 1116/2007 369 0.25 4.02 MW20 3/27/2008 168 1.4 4.19 I U I U I U 0.4 U 2 U IU I U MW20 7/10/2008 319 1.53 4.62 IU IU I U o U 2 U I U I U MW20 1012/2008 274 0 4.05 IU I UL I U 0.132 L 2 U IU I UL • MW21 Jan-OO NO NO NO MW21 31112006 430.2 3.03 4.53 IU I U I U 0.4 U 2 U I U I U MW21 11/812007 422 2.35 3.89 MW21 7/10/2008 320 3.68 4.72 IU IU I U o U 2 U I U I U MW22 111100 15 33 NO MW22 7/15/2008 191 0.04 4.29 0.758 J I U I U o U 2 U I U I U MW22 10/8/2008 208 0 3.94 IU I U I U 0.4 U 2U I U I U MW22 1/12/2009 213 0 4.1 0.334 J I U I U 0.4 U 2 U I U I U MW22 4/8/2009 143 3.33 .5.17 I U I U I U 0.4 U 2 U I U I U MW22 7/27/2009 136 0 4.52 IU I U I U 0.4 U .2 U I U I U MW22 10/14/2009 225 0 4.81 IU I U I U 0.4 U 2 U I U I U MW23 111100 71 75 NO MW23 3/212006 299.9 6.26 4.97 37.2 29 I U O.4U 2U I U 0.351 J MW23 10/22/2007 196 1.44 5.18 MW23 1122/2008 -314.7 0.85 5.27 138 I U I U 0.4 U 2 U I U I U MW23 3/25/2008 -169.9 0.89 5.77 55.5 I U 0.341 J 0.4 U 2 U I U I U MW23 6/10/2008 42.5 0.2 4.72 46.8 I U 0.531 J 0.4 U 2 U I U I U MW23 10/2/2008 -125 0 '6.15 58.2 I U 0.621 J 0.4 U 2 U I U I U MW23 11712009 -122 0 6.01 42.4 I U l.l5 0.4 U 2 U I U I U MW23 4/912009 -136 0 6.13 0.483 J I U 0.26 J 0.4 U 2 U I U I U MW23 7/23/2009 -209 0.05 6.76 4.63 I U 0.358 J 0.4 U 2 U .1 U I U MW23 10114/2009 -191 0 7.24 0.487 J I U IU 0.4 U 2 U I U I U MW24 1/1/00 72 41 NO MW24 3/2/2006 336.4 1.39 4.69 64.1 14.5 0.602 J 0.4 U 2 U I U I U MW24 10/22/2007 414 0.91 4.67 MW24 1/2212008 27 0.64 5.53 31.8 8.73 IU 0.4 U 2 U I U I U

MW24 3/25/2008 53 0.1 5.44 29.4 5.25 0.417 J 0.4 U 2 U [ I U I U MW24 6/912008 89.7 0.73 5.51 35.1 16.2 0.596 J 0.4 U 2 U I U I U

Page 50f8 MACTEC Project: 3350092494 • Prepared by: AECOM 1211712010 4.0_0eJiverables\4.I_Reports\Oraft\Tables\4.1 STl4 by well Checked by: SWR 01/25/2010 Joilll.Base Andrews - First Five-Year Review November 2010 MA CTEC Engineering and Consulting, Illc. Table 4.1 ST-14 Groundwater Monitoring Data Summary

ORP DO TCE Benzene m,p-Xylene o-Xylene Toluene • Location Sample Date (mV) (mWL) ,pH (s.u.) (llglL) CT ("gIL) VC (llglL) (llglL) (llglL) (llglL) (llglL) SRG - - - - 5 5 , 2 5 500 * 500 * 300 MW24 1012/2008 68 0 5.27 25.2 L 17.4 L 0.39 L 0.4 UL 2 UL I UL I UL MW24 11712009 -50 0 5.65 26.6 4.26 0.74 J 0.4 U 2 U I V I U MW24 4/9/2009 -82 0 5.65 26.2 13.3 0.384 J 0.4 V 2 V I V I V MW24 7/23/2009 -108 0 6.03 22.7 7.26 0.669 J 0.4 U 2 V I V I U MW24 10/14/2009 -82 0 6.41 18.4 4.47 0.321 J 0.4 V 2 V IV I V MW25 111100 1.1 NO NO MW25 2/2812006 273.6 1.71 4.58 IU IU I U 0.4 U 2 V IV I V MW25 10/2412007 424 0.66 4.01 MW25 4/8/2008 382.7 0.92 4.41 0.262 J I U I V 0.4 U 2 U I V I U MW25 7/10/2008 210 0.57 4.65 I U I U I U Om 2 U I V I V MW25 1016/2008 339 0.47 4.2 I U I U I U 0.4 V 0.505 J I V 0.434 J MW25 1/912009 402 0.12 2.43 I U I U I U 0.4 V 2 V IV IV MW25 4/8/2009 444 1.66 3.94 I U IU I V 0.4 V 2 V I V IV MW26 111100 NO NO NO J MW26 3/1/2006 34.2 0.05 5.82 IV I U I V 0.4 V 2 V I V I V MW26 10/2512007 76 ' 0.07 5.31 MW26 4/8/2008 29.1 0.82 5.75 0.33 J I U I V 0.4 U 2 V IV I U MW26 7/1012008 19 0.71 5.74 I V I V I U o V 2 U I V I U MW26 1016/2008 9 3.64 6.3 I V IV I V 0.4 V 2 U I V I V MW26 1/12/2009 59 0 5.23 I V IV I U 0.4 V 2 V IV I V MW26 4/812009 40 0.38 5.32 I V I V I V 0.4 V 2 V I V I U MW27 111100 2.5 20 NO MW27 312/2006 406.5 1.29 4.29 5.31 3.72 I V 0.4 V 2.V I V IV MW27 1111/2007 440 0.29 4.56 MW27 4/8/2008 392.5 0.34 4.32' 2.27 4.06 I V 0.4 V 2 U I V 1 V MW27 711 0/2008 417 2.4 4.26 1.36 3.94 I V o U 2 U IV I V MW27 101712008 373 5.47 . 3.61 1.42 M 3.14 J I U 0.4 V· 2 V IV IV MW27 1/1312009 407 1.13 3.95 1.53 1.93 I U 0.4 V 2 V I V 1 V • MW27 4/15/2009 402 1.04 3.93 I.71 4.42 I U 0.4 V 2 V I V I V MW27 7/2312009 241 1.52 4.22 2.09 2.1 I U 0.4 V 2 V IV I V MW27 10/16/2009 386 0 4.23 2.88 3.89 IV 0.4 V 2 V IV I V MW28 111/00 NO NO 0.5 MW29 111100 NO NO NO MW29 312/2006 268.7 7.36 5.56 I V I V I V 0.4 U 2 U I V 1 V MW29 1112/2007 205 3.1 5.27 MW29 4/912008 408.7 2.18 4.27 I U I V I V 0.4 V 2 U I V I V MW29 7/15/2008 180 1.51 5.24 I V IV I V o V 2 V I V I V MW29 7/28/2009 189 0.24 5.53 I U IV I V 0.4 V 2 V I V 1 V MW29 10/14/2009 166 1.73 5.53 I V I U I U 0.4 V 2 V IV IV MW30 111100 NO NO 0.9 MW30 2/2812006 128.8 1.06 5.71 I V IV I U 0.4 V 2 V I V I V MW30 1118/2007 336 0.92 4.3 MW30 41712008 272.9 .3.81 4.87 I U I U I U 0.4 V 2 V IV I V MW30 7/1112008 311 4.64 4.95 I U I V I U o V 2 V I V IV MW30 101712008 339 2.87 4.7 I V I V I V 0.4 V 2 U IV I V MW30 1114/2009 184 3.63 4.3 I V I U I U 0.4 U 2 U I U I U MW30 4/8/2009 268 3.13 4.46 I V I U I U 0.4 U 2 U I V I U MW30 7/29/2009 214 4.87 4.86 I V I U I V 0.4 U 2 U I U I V MW30 10/12/2009 326 3.99 4.73 I V I V I U 0.4 V 2 V I V IV MW31 1/1100 _ 39 NO NO MW31 2/27/2006 420.23 3.8 4.35 0.579 J IU I V 0.4 U 2 V I U I U MW31 10/25/2007 300 2.03 5.2 MW31 41712008 259.9 4.21 5.33 13.4 I V I U 0.4 V 2 V I V I V MW31 711 0/2008 388 5.02 5.04 0.607 J I U I V o V 2 V I V I V MW31 101712008 221 2.39 5.35 9.16 I U I U 0.4 V 2 U I V I V MW31 1/9/2009 237 4.17 5.16 9.97 I V I V 0.4 U 2 U I V I V

Page 6 of 8 MACTEC Project: 3350092494 • Prepared by: AECOM 12117/2010 4.0_Oeliverables\4.I_Reports\Oraft\Tables\4.1 STI4 by well Checked by: SWR 01/25/2010 Joillt Base Andrews - First Five-Year Review November 2010 MA CrEC Ellgineering and Consliiting, Illc. Table 4.1 ST-14 Groundwater Monitoring Data Summary

ORP DO TCE Benzene m,p-Xylene o-Xylene Toluene • Location Sample Date (mY) (mglL) [pH (s.u.) (~glL) CT ("giL) VC (,,~/L) (J.lglL) ("gIL) ("gil) (J.lglL) SRG - - - - 5 5 2 5 500 * 500 * 300 MW31 4/9/2009 254 3.86 5.08 9.35 I V I V 0.4 V 2 V I V I V MW31 7/27/2009 150 3.02 4.97 10.4 IV I V 0.4 V 2 V I V I V MW31 10/1512009 236 1.64 5.26 17.8 IV I V 0.4 V 2 V I V I V MW32 1/1/00 160 22 NO MW32 31112006 294.4 1.17 4.53 165 7.06 I V 0.4 V 2 V I V I V MW32 10/24/2007 427 0.34 4.03 MW32 111/08 388 3.46 2.5 V 0.394 J .5 V 2.5 V 2.5 V MW32 3/2512008 179.2 6.59 5.67 1 V IUJ I V 0.4 V 2 V IV IV MW32 6/12/2008 201 0.24 4.75 IV 4.26 IV 0.31 J 2 V IV IV MW32 10/6/2008 233 0.21 3.65 713 3.89 J 5 V 2 V IOV 5 V 5 V MW32 111312009 380 0.16 2.91 752 2.52 J 5 V 2 V 10 V 5 V 5 V MW32 41712009 344 l.3 4.16 835 2.86 2 V 0.8 V 4 V 2 V 2 V MW32 7/30/2009 366 0 4.39 694 2.02 J 5 V 2 V IOV 5 V 5 V MW32 10/1412009 -56 0 6.03 733 5 V 5 V 2 V 10 V 5 V 5 V MW33 1/1100 76 NO NO MW33 2128/2006 389.4 0.95 4.65 32.2 I V I V 0.4 V 2 V I V I V MW33 111112007 400 0.6 4.7 MW33 111/08 24.2 I V .I V 0.4 V 2 V IV I V MW33 3/24/2008 225 0.73 4.15 22.4 1 V IU 0.4 U 2 U IU 1 U MW33 6/1312008 459.3 0.88 3.42 19 I NO I NO o NO 2 NO I NO I NO MW33 10/6/2008 237 0.05 3.49 21.2 I V I V 0.4 () 2 V I U I U MW33 118/2009 321 0.29 4.28 16.4 I V I U. 0.4 U 2 V I U I U MW33 4/912009 380 1.1 4.19 21.6 I V I U 0.4 V 2 U I U I V MW33 7/29/2009 207 0.56 4.74 22.8 I U I U 0.4 V 2 U I U I V MW33 10/12/2009 352 0 4.57 16 1 U I V 0.4 V 2 U I V I V MW34 1/1100 54 NO 1.4 MW34 3/2/2006 237.9 1.26 4.17 137 I U I V 0.71 2 U IU I V MW34 1012312007 426 0.13 4.36 MW34 1/2212008 -89.6 4.08 5.13 105 I U I V 0.503 2 U I U I V MW34 3/2412008 233 0.38 4.88 100 I V I U 0.493 2 V I U I V MW34 6/12/2008 89 0 5.78 96.1 I V I U 0.497 2 V I U I U MW34 10/2/2008 -117 0 5.75 96.1 L I UL I UL 0.418 L 2 UL I UL I UL MW34 11712009 -97 0 5.87 26.8 1 U IU 0.562 2 U I U 1 U MW34 41712009 -174 0 5.88 29,9 I U IV 0.52 2 U 1 V I V MW34 7/2212009 -131 0 6.09 49.2 I V 1.08 0.393 J 2 V 1 V I U MW34 1011612009 -117 0 6.7 IV I V 0.87 J 0.462 2 V 1 U I U MW35 1/1103 77 3.4 8.87 4.2 NO NO MW35 31212006 35.9 5.05 12.35 1.01 I U I U 0.4 V 2 U I V 0.256 J MW35 11/112007 -34 2.27 11.79 MW35 111/08 7.8 I V I U 0.4 U 2 U I V I U MW35 4/3/2008 -59 5.26 1l.35 5.37 1 U 1 U 0.4 U 2 U I V 1 U MW35 7/10/2008 -97 4.14 -14.31 5.56 1 U I U o U 2 U I V 1 U MW35 101712008 -124 1.7 13.2 10.8 I U , I U 0.4 U 2 U I V I U MW35 119/2009 -89 5.72 11.76 8.85 I V I U 0.4 U 2 U I U I U MW35 411 012009 -50 6.44 11.8 7.33 I V I V 0.4 U 2 U I U I U MW35 7/2712009 -96 4.27 11.91 7.72 I V I V 0.4 U 2 V I U I U MW35 10/16/2009 -86 2.71 12.4 7.4 I V I V 0.4 U 2 V I V I U MW36 1/2/03 -3 4.26 11.41 NO NO NO MW37 1/3/03 277 2 4.45 340 NO 0.8 MW37 31112006 379.8 5.36 4.41 475 I V 2.01 0.611 2 U I V I U MW37 1111/2007 359 0.22 3.91 MW37 112312008 91 8.85 5.05 574 I U 3.76 0.661 2 U I V I U MW37 3/26/2008 220 3.28 4.25 684 5 U 2.96 J 0.96 J 10 V 5 V 5 U MW37 6/18/2008 205 1.53 4.75 901 IU 3.48 0.817 2 U 1.06 IV MW37 10/312008 337 0 4.18 1700 10 V 8.52 J 4 V 20 V 10 V 10 V MW37 119/2009 297 3.79 3.33 908 5 V 2.83 J 0.766 J 10 V 5 V 5 V

Page 7 of 8 MACTEC Project: 3350092494 • Prepared by: AECOM 12/17/2010 4.0_Deliverables\4.I_Reports\Oraft\Tables\4.1 STl4 by well Checked by: SWR 01125/2010 Joint Base Andrews - Firsl Five-Year Review November 2010 MA CrEC Engineering and Consulting, Inc. Table 4.1 ST-14 Groundwater Monitoring Data Summary

ORP DO TCE Benzene m,p-Xylene o-Xylene Toluene • Location Sample Date (my) (mglL) pH (s.u.) ("gil ) CT (,,~/L) VC ("gIL) ("giL) ("giL) ("gIL) ("g/L) SRG - - - - 5 5 2 5 500 * 500 * 300 MW37 4/9/2009 328 3:87 4.11 1120 5 U 5 U 4 U 10 U 5 U 5 U MW37 7/30/2009 197 1.26 4.61 1010 IOU 3.37 J ' 4 U 20 U 10 U 10 U MW37 10/12/2009 279 0 4.41 1020 10 U 5.15 J 4 U 20 U 10 U 10 U MW38 114/03 177 2.3 5.85 ND ND ND MW38 3/712006 286.6 2.88 5.02 I U ] U I U 0.4 U 2 U I U I U MW38 ]11612007 308 0.51 4.52 MW38 411/2008 275,6 3.85 5,01 1 U I U ] U 0.4 U 2 U I U 1 U MW38 7/10/2008 267 3 5.25 I U I U I U o U 2 U I U I U MW38 9/30/2008 211 1.59 5.25 I U I U I U 0.4 U 2 U I U I U

Notes: SRGs = Site Remediation Goals from Final Record of Decision, ST14, (USAF, US EPA, and MDE, 2007) ORP = oxidation-reduction potential TCE = trichloroethene CT = carbon tetrachloride VC = vinyl chloride mV = millivolts s.u. = standard units mgIL =milligrams per liter uglL = micrograms per liter * The SRG in the ROD is 500 "giL for total xylenes.

Data Flag Definitions: J = The analyte was positively identified; the quantitation is an estimation U = less than the reporting limit L = Estimated and bias-low quantity. The actual value is expected to be higher. ND = Not Detected, detection limit unknown

Page 8 of8 MACTEC Project: 3350092494 Prepared by: AECOM 12117/2010 4.0_DeIiverables\4.I_Reports\Draft\Tables\4.1 STI4 by well Checked by: SWR 01/25/2010 Joint Base Andrews - First Five- Year Review November 2010 M4CTEC Engineering and Consulting, Inc .

Table 4.2 • ST-14.Summary of Toxicity Value Updates

Chemical of Oral Referece Dose (RID) [m2/kWdayl Inhalation Reference Dose (RID) [m2lk2/dayl Oral Cancer Slope Factor (CSF) [mglkg/dayr\ Inhalation Cancer Slope Factor (CSF) [m2/k2/day!'\ Potential Concern Final RI Updated Final RI Updated Final RI Updated Final RI Updated (COPC) Value Source Value Source Value Source Value Source Value Source Value Source Value Source Value Source

Arsenic NA NA 4.3E-06 REL Barium om IRIS 0.2 IRIS Benzo( a)anthracene NA NA NA NA 0.39 CALEPA Benzo(a)pyrene NA NA 3.1 EPA 3.9 CALEPA Benzo(b )t1uoranthene NA NA NA NA 0.39 CALEPA alpha-BHC 0.0003 IRIS O.OOS IRIS' beta-BHC 0.0003 IRIS NA IRIS delta-BHC 1.8 IRIS NA IRIS 1.8 IRIS NA IRIS gamma-BHC 0.0003 IRIS NA IRIS 1.3 Heast .1.1 CALEPA NA NA 1.1 CALEPA bis(2-ethylhexyl)phthalate (chronic) 0.0037 EPA ND IRIS 0.014 EPA 0.0085 CALEPA Cadmium (chronic) 0.0002 NCEA 5.7E-06 REL Carbon tetrachloride 0.0007 IRIS 0.004 IRIS proposed 5.00E-02 ATSDR 2.90E-02 IRIS proposed 0.13 IRIS 0.07 IRIS proposed 0.053 IRIS 0.021 IRIS Proposed alpha~Chlordane 2.00E-04 IRIS ?OOE-OI IRIS gamma-Chlordane 2.00E-04 IRIS 7.00E-OI IRIS Chloroform (chronic) I AOE-02 EPA 8.60E-02 REL Cobalt 0.02 EPA 0.0003 PPRTV 5.70E-06 EPA l.7E-06 PPRTV 9.SE+00 EPA 9.0E+00 PPRTV Dibenzo(a,h)anthracene NA NA 3.9E+00 CALEPA Dibenzofuran 0002 EPA 0.001 PPRTV 1,2-Dibromoethane 2 IRIS NA IRIS cis(l ,2-dichloroethene) (chronic) 0.01 PPRTV 0.006 IRISproposed Indeno(I,2,3-cd)pyrene (chronic) NA NA 3.9E-OI CALEPA Iron 0.3 EPA 0.7 PPRTV Methyl-ter! butyl ether 4.00E-03 EPA 1.80E-03 CALEPA NA NA 1.8E-03 CALEPA 4-Methylphenol NA NA 0.17 REL • PCE 0.01 IRIS 0.004 IRIS proposed 0.14 EPA 0.07710005 ATSDR/IRlS proposed SAOE-OI EPA 1.00E-OI IRIS proposed 2.0E-03 EPA 70E-02 IRIS proposed Thallium (chronic) 6.5E-05 IRIS 0.00008 IRIS TCE 3.00E-04 EPA NNO.0004 NNIRlS proposed 0.011 EPA 0.0014 IRIS proposed 4.0E-0 I EPA 1.3E-02/2.0E-02 CALEPAJIRlS proposed 4.0E-OI EPA 7.0E-3/lAE-2 CALEPNIRlS proposed

Notes: IRIS - Integrated Risk Information System (December 2009) IRIS Proposed - Integrated Risk Information System (December 2009) - a Draft IRIS Assessment has been published for external peer review. ATSDR ~ Agency for Toxic Substances and Disease Registry Minimum Risk Level (MRL) (December 2008) CAL EPA - Califorrnia Environmental Protection Agency; slope factors (July 2009) and Reference Exposure Levels (RELs) (December 200S) NCEA - National Center for Environmental Assessment (NCEA) provisional dose-response value PPRTV - Provisional Peer Reviewed Reference Toxicity Value HEAST - Health Effects Assessment Summary Tables 2008 (obtained from Oak Ridge National Library Regional Screening Levels for Chemical Contaminants at Superfund Sites) PPRTV - Provisional Peer Reviewed Reference Toxicity Value

MACTEC Project: 3350092494 Prepared by: KASK 01/12/2010 • P:IProjec\s\Andrews AFB EnvironmentallFive-year reviewsl4 O_DeliverablesI41_ReportsIFmaIITablesI4.:! ST-14 DR summary Page I of I Checked by: JHP 0111212010 Joint Base Andrews - First Five- Year Review November 2010 MACTEC Engineering and Consulting. Inc. Table 7.1 FT -03 Groundwater Monitoring Data Summary

• Site ID: FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 Location ID: MWOI-FT03 MWOI-FT03 MWOI-FT03 MWOI-FT03 MWOI-FT03 MWOI-FT03 MWOI-FT03 MW02-FT03 MW02-FT03 MW02-FT03 MW02-FT03 Sample ID: Regulatory 2037 2038 MWOIFT03GW5108 . FT03-MWOI MWOIFT03GW6362 MWOIFT03GW6587 MWOIFT03GW6689 2039 MW02FT03GW5109 MW02FT03GW6363 MW02FT03GW6588 Sample Date: Standard 4/112002 4/112002 4/8/2003 7/1112005 10/30/2007 911712008 3112/2009 4/3/2002 4/9/2003 10125/2007 911612008 Sample Type: Sample Duplicate Sample Sample Sample Sample Sample Sample Sample Sample Sample

Metals - SW846 60108 Arsenic NA NA NA 0.0048 F NA <0.03 NA NA NA <0.01 0.0053 F Chromium NA NA NA 0.00092 F NA < O.oJ NA NA NA <0.01 <0.01

Metals - SW846 60108 Arsenic <0.03 < 0.03 <0.03 <0.03 <0.01 NA <0.03 <0.03 0.0064 F NA NA Chromium <0.01 <0.01 0.0024 F 0.0029 F <0.01 NA <0.01 0.0257 0.0026 F NA NA

<9.8 <9.9 <10 < 0.0092 <10.4 < 10 < 10 <9.5 < 10 < 11.8 <10 <9.8 <9.9 < 10 <6.2 < 10.4 <10 < 10 <9.5 <10 < 11.8 < 10

ounds - SW846 82608 u fL '. < I < I .< 1 <0.4 < 1 < I < I < I < I 1.6 8 < I

Notes: Regulatory Standards from USEPA's National Primary and Secondary Drinking Water Standards-Maximum Contaminant Levels (MCLS) (USEPA, June 2003) mg/L = milligrams per liter ugIL = micrograms per liter • Data Flag Definitions: < = Less than the Reporting Limit B = Blank contamination: The analyte was found in an associated blank above 112 the Reporting Limit, as well as in the sample F = Found: The analyte was positively identified but the associated concentration is an estimation above the Method Detection Limit and below the Reporting Limit J = The result is estimated due to discrepancies in meeting certain analyte-specific quality control criteria NA = Not Analyzed UJ = The analyte was not detected: however. the result is estimated due to discrepancies in meeting certain analyte-specific quality control criteria

'"h..RESULTEXCEEDS;REGULATORY,·S:TANDA'iW······ . .. "~. '. .. __ .-...... w.o.'. . . ..".;:~::....~_.lli.<.~, •.. ,::" .. _......

MACTEC Project: 3350092494 Prepared by: M. Barker 01/26/20 I 0 • P:IProjectslAndrews AFB Environmental\Five-year reviewsI4.0_DeliverablesI4.I_ReponsIFinalITablesI7.1 FT03-BY WELL 1-28-10 Page lof6 Checked by: C.Crow 01/27/2010 Joint Base Andrews - First Five- Year Review November 2010 MACTEC Engineering and Consulting, Inc. Table 7.1 FT-03 Groundwater Monitoring Data Summary

Site ID: FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 ' FT03 FTO] Location ID: MW02-FT03 MW03-FT03 MW03-FT03 MW03-FT03 MW03-FT03 MW03-FT03 MW03-FT03 MW03-FT03 MW04-FT03 MW04-FT03 MW04-FT03 Sample ID: Regulatory MW02FT03GW6690 2040 MW03FT03GW5110 MW03-FT03-03 FT03-MW03 MW03FT03GW6364 MW03FT03GW6589 MW03FT03GW6691 2041 MW04FT03GW51 I I FT03-MW04 Sample Date: Standard 3/1112009 4/212002 41712003 4/9/2004 711112005 10/26/2007 911712008 3/12/2009 4/312002 4/8/2003 7112/2005 Sample Type: Sample Sample Sample Sample Sample Sample Sample Sample Sample Sample Sample

Metals - SW846 60108 Arsenic < 0.03 NA NA <0.01 < 0.03 NA NA NA NA NA <0.03 Chromium < 0.01 NA NA . <0.01 <0.01 NA NA NA NA NA <0.01

Metals - SW846 60108 Arsenic NA <0.03 <0.03 <0.011 <0.03 < 0.01 <0.03 <0.03 O.O~Z;W:J· 0.0073 F 0.0049 F Chromium NA <0.01 0.0064 F 0.003 B 0.0018 F <0.01 <0.01 <0.01 <0.01 <0.01 0.0018 F

Semi-Volatile 0 Benzo(a)pyrene <10 <9.6 < 10 <0.19 < 0.0092 < 10.2 < 10 < 10 <9.4 <10 0.047 Naphthalene < 10 <9.6 < 10 <0.94 < 6.2 < 10.2 <10 <10 <9.4 <10 <6.2

ounds - SW846 82608 u < I < I < I

Notes: Regulatory Standards from US EPA's National Primary and Secondary Drinking Water Standards-Maximum Contaminant Levels (MCLS) (USEPA, June 2003) mg/L = milligrams per liter ug/L = micrograms per liter • Data Flag Definitions: < = Less than the Reporting Limit B = Blank contamination: The analyte was found in an associated blank above 112 the Reporting Limit, as well as in the sample F = Found: The analyte was positively identified blit the associated concentration is an estimation above the Method Detection Limit and below the Reporting Limit J = The result is estimated due to discrepancies in meeting certain analyte-speci NA = Not Analyzed UJ = The analyte was not detected: however, the result is estimated due to discr ~~!l~T ~GJi:~DS RE9IIk~tQ~YSf,fNDJ\~~;j-'~

MACTEC Project: 3350092494 Prepared by: M. Barker 01126/2010 • P:IProjec(slAndrews AFB Envirorunenta\IFtve-year reviewsI4.0_Deliverab\esI4.I_ReportsIFinalITablesI7.\ FT03-BY WELL \-28-\0 Page 2 of6 Checked by: C.Crow 01/27/2010 Joint Base Andrews - First Five- Year Review November 2010 MACTEC Engineering and Consulting, Inc. Table 7.1 FT -03 Groundwater Monitoring Data Summary

• Site ID: FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 Location ID: MW04-FT03 MW04-FT03 MW04cFT03 MW05-FT03 MW05-FT03 MW06-FT03 MW06-FT03 MW06-FT03 MW06-FT03 MW06-FT03 MW06-FT03 Sample ID: Regulatory MW04FT03GW6365 MW04FT03GW6590 . MW04FT03GW6692 2042 MW05FT03GW5112 2043 MW06FT03GW5113 \tfW06FT03GW5113-F FT03-MW06 MW06FT03GW6367 MW06FT03GW6592 Sample Date: Standard 101'1.6/2007 9/1912008 3/12/2009 512012002 41712003 5/20/2002 411012003 4110/2003 7/12/2005 10/26/2007 9/17/2008 Sample Type: Sample Sample Sample Sample Sample Sample Sample Duplicate Sample Sample Sample

Metals - SW846 60108 Arsenic NA 0.0062 F 0.0062 F NA NA NA NA NA <0.03 < 0.01 NA Chromium NA 0.00072 F <0.01 NA NA NA NA NA <0.01 < 0.01 NA

Metals - SW846 60108 Arsenic 0.0049 F NA NA <0.03 <0.03 <0.03 <0.03 0.005 F <0.03 < 0.01 < 0.03 Chromium < 0.01 NA NA <0.01 <0.01 <0.01 0.0024 F 0.0023 F 0.0076 F <0.01 < 0,01

ounds - SW846 8270C u < 10.1 < 10 <10 <9.5 < 10 <9.2 < 10 <10 < 0.0092 < 10.3 < 10 ffiiWIKor~7~F~ < 10 ~"Il\"o£J7~5F.a <9.5 <\0 <9.2 <\0 < 10 < 6.2 < 10.3 <10

ounds - SW846 82608 u i~fl~7$iB~~ < 1 ~;J~:O;6ijjJFim-3i~l < I < 1 < 1 < 1 < I <0.4 < 1 < 1.0

Notes: Regulatory Standards from USEPA's National Primary and Secondary Drinking Water Standards-Maximum Contaminant Levels (MCLS) (USEPA, June 2003) mg/L = milligrams per liter ug/L = micrograms per liter • Data Flag Definitions: < = Less than the Reporting Limit B = Blank contamination: The analyte was found in an associated blank above 112 the Reporting Limit. as well as in the sample F = Found: The analyte was positively identified but the associated concentration is an estinJation above the Method Detection Limit and below the Reporting Limit J = The result is estimated due to discrepancies in meeting certain analyte-speci NA = Not Analyzed UJ = The analyte was not detected: however, the result is estimated due to disci" r~~~!~§!~D®U!iATO:BY;1i1AEQ~!_i..•.:~:]

MACTEC Project: 3350092494 Prepared by: M. Barker 01/26/2010 P:IProjects\Andrews AFB EnvironmentallFive-year reviewsI4.0_DeliverablesI4.I_Rep0rlsIFinaiITablesI7.1 FT03-BY WELL 1-28-10 Page 3 of6 Checked by: C.Crow 01/27/2010 Joint Base Andrews - First Five- Year Review November 2010 MACTEC Engineering and Consulting, Inc. Table 7.1 FT-03 Groundwater Monitoring Data Summary

• Site ID: FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 . Location ID: MW06-FT03 MW07-FT03 MW07-FT03 MW07-FT03 MW07-FT03 MW07-FT03 MW07-FT03 MW07-FT03 MW07-FT03 MW08-FT03 MW08-FT03 Sample ID: Regulatory MW06FT03GW6694 2044 MW07FT03GW5114 MW07FT03GW6368 MW07FT03GW6369 MW07FT03GW6593 MW07FT03GW6594 MW07FT03GW6695 MW07FT03GW6696 2045 MW08FT03GW5115 Sample Date: Standard 3/12/2009 5/17i2002 4/10/2003 10/30/2007 10/30/2007 911712008 911712008 3/12/2009 3/12/2009 3/29/2002 4/512003 Sample Type: Sample Sample Sample Sample Duplicate Sample Duplicate Sample Duplicate Sample Sample

Metals -SW846 60108 Arsenic < 0.03 NA NA NA NA NA NA NA NA NA NA Chromium <0.01 NA NA NA NA NA NA NA NA .NA NA

Metals - SW846 60108 Arsenic NA < 0.03 0.0057 F <0.01 <0.01 < 0.03 <0.03 < 0.03 < 0.03 <0:03 < 0.03 Chromium NA <0.01 0.0042 F <0.01 0.0016 F <0.01 <0.01 < 0.01 < 0.01 <0.01 < 0.01

ounds - SW846 8270C u IL < 10 <9.6 < 10 < 10.4 UJ <10.4 <10 < 10 <10 <9.4 < 10 < 10 <9.6 <10 < 10.4 UJ <10.4 < 10 < 10 <10 <9.4 <10

ounds - SW846 82608 u < 1.0 < 1.0 ·OJ5. F ;Ji~.,·

Notes: Regulatory Standards from USEPA's National Primary and Secondary Drinking Water Standards-Maximum Contaminant Levels lMCLS) (US EPA, lune 2003) mgIL = milligrams per liter ugIL = micrograms per liter • Data Flag Definitions: < = Less than the Reporting Limit B = Blank contamination: The analyte was found in an associated blank above 1/2 the Reporting Limit, as well as in the sample F = Found: The analyte was positively identified but the associated concentration is an estimation above the Method Detection Limit and below the Reporting Limit 1 = The result is estimated due to discrepancies in meeting certain analyte-speci NA = Not Analyzed Ul = The analyte was not detected; however, the result is estimated due to discr fREiJL~fl~§j~pii,MG]Er:ffiRYRWIlA@1:-,~,~,i

MACTEC Project: 3350092494 Prepared by: M. Barker 01/26/2010 • P'IProjects\Andrews AFB EnvironmentallFive-year reviewsI4.0_Deliverab\esI4.\_ReponsIFinalITab\esI7.\ Ff03-BY WELL \-28-10 Page 4 of6 Checked by: C.Crow 01/27/2010 Joint Base Andrews - First Five-Year Review November 20 I 0 M4CTEC Engineering and Consulting, Inc. Table 7.1 FT-03 Groundwater Monitoring Data Summary

• Site ID: FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 FT03 Location ID: MW08-FT03 MW08-FT03 MW08-FT03 MW09-FT03 MW09-FT03 MW09-FT03 MW09-FT03 MW09-FT03 MW09-FT03 MWIO-FT03 MWIO-FT03 Sample ill: Regula/ory FT03-MW08 MW08FT03GW667I MW08FT03GW6697 2046 MW09FT03GWSI16 MW09FT03GW637I MW09FT03GW6672 MW09FT03GW6680 MW09FT03GW6698 2047 MWIOFT03GWSI17 Sample Date: Standard 7/111200S 12/16/2008 311112009 3/29/2002 41S12003 10/2S12007 12/19/2008 1211912008 3/12/2009 411/2002 41712003 Sample Type: Sample Sample Sample Sample Sample Sample Sample Duplicate Sample Sample Sample

Metals - SW846 6010B Arsenic <0.03 NA NA NA NA <0.01 <0.03 <0.03 <0.03 NA NA Chromium <0.01 NA NA NA NA <0.01 <0.01 < 0.01 <0.01 NA NA

Metals - SW846 6010B Arsenic <0.03 <0.03 <0.03 <0.03 < 0.03 NA NA NA NA <0.03 <0.03 Chromium 0.0014 F <0.01 <0.01 <0.01 0.0023 F NA NA NA NA <0.01 <0.01

ounds - SW846 8270C u IL < 0.0092 <10 < 10 <9.4 < 10 < 10.2 < 10 < 10 <10 <9.9 <\0 <6.2 < 10 < 10 <9.4 <10 < 10.2 <10 <10 <10 <9.9 < 10

Dunds - SW846 8260B u L ·<0.4 < I < 1

Notes: Regulatory Standards from USEPA's National Primary and Secondary Drinking Water Standards-Maximum Contaminant Levels (MCLS) (USEPA, June 2003) mgIL = milligrams per liter ugIL = micrograms per liter • Data Flag Definitions: < = Less than the Reporting Limit B =Blank contamination: The analyte was found in an associated blank above 112 the Reporting Limit, as well as in the sample F = Found: The analyte \vas positively identified but the associated concentration is an estimation above the Method Detection Limit and below the Reporting Limit J = The result is estimated due to discrepancies in meeting certain analyte-speci NA =Not Analyzed UJ = The analyte was not detected; however, the result is estimated due to discr 1iESlT~!;~GEEDS:REGY)l~~Ql~xJ~@D.•··'

MACTEC Project: 3350092494 Prepared by: M. Barker 01126/2010 • P:IProjectslAndrews AFB EnvironmentallFive-year reviewsI4.0_DehverablesI4.I_ReportsIFinaIITablesI7.I FT03-BY WELL 1-28-10 Page S of6 Checked by: C.Crow 01/27/2010 Joint Base Andrews - First Five- Year Review November 2010 MACTEC Engineering and Consulting. Inc. Table 7.1 FT -03 Groundwater Monitoring Data Summary

Site ID: FT03 FT03 FT03 FT03 FT03 FT03 FT03 Location ID: MWIO-FT03 MWIO-FT03 MWIO-FT03 MWIO-FT03 MWII-FT03 MW12-FT03 MW12-FT03 Sample ID: Regulatory FT03-MWIO MWIOFT03GW6372 MW IOFT03GW6597 MWIOFT03GW6699 FT03-MWII FT03-MWI2 FT03-MW12 Sample Date: Standard 711112005 10/25/2007 9116/2008 3/1212009 711112005 711112005 7/1112005 Sample' Type: Sample Sample Sample Sample Sample Sample Duplicate

Metals - SW846 60]08 Arsenic <0.030 <0.01 NA < 0.03 0.0059 F <0.03 <0.03 Chromium <0.01 <0.01 NA < 0.01 <0,01 0.0021 F 0.0012 F

Metals - SW846 60108 Arsenic 0.0059 F NA 0.0046 F NA 0.0077 F <0.03 <0.03 Chromium 0.0039 F . NA <0.01 NA 0.064 0.0083 F O.Q]

< 0.0092 < 10.8 < 10 <10 0.013 < 0.0092 < 0.0092 < 6.2 < 10.8 < 10 <10 < 6.2 < 6.2 < 6.2

ounds - SW846 82608 u O.35;i'F\·)Ja~ < I

Notes: Regulatory Standards from USEPA's National Primary and Secondary Drinking Water Standards-Maximum Contaminant Levels (MCLS) (US EPA. June 2003) mgiL = milligrams per liter ugiL = micrograms per liter • Data Flag Definitions: < = Less than the Reporting Limit B = Blank contamination: The analyte was found in an associated blank above 112 the Reporting Limit. as well as in the sanlple F = Found: The analyte was positively identified but the associated concentration is an estimation above the Method Detecti~n Limit and below the Reporting Linlit J = The result is estimated due to discrepancies in meeting certain analyte-speci NA = Not Analyzed UJ = The analyte was not detected; however, the result is estinlated due to discr ~slILij:xCEEDS:~ORY;ST~p~

MACTEC Project: 3350092494 •• Prepared by: M. Barker 01126/2010 P:IProjectslAndrews AFB EnvironmentallFive-year reviewsI4.0_DeliverablesI4.I_ReportsIFinaIITablesI7.1 Fr03-BY WELL 1-28-10 Page 60f6 Checked by: C.Crow 01/27/2010 » "'tI "'tI rn 2 C >< • »

• Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011) •

APPENDIX A PUBLIC NOTICES

•

• P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0':" Oeliverables\4.1_Reports\Final\AndrewsAFB _5-Yr Review _Revised March 201l.doc CAPITAL FLYER - Friday. DecemberJ.8. 2009 Public Notice: Five yearreview . .of.;,environmental sites:-' ,-, , _. -: .. :". The~Forceis cummtly performing detaiiingthe five-year reviews in \Natch the first ~ewide five-year review at August 2010. Fb110wing releaEJe of the Andrews Air Force Base (AFB), Prince reports, the Air Fofre will alSo issue a Your George's _CountY. Maryland, in accor·public notice and fact sheet. Questions daDce with the i'eqUirements of the orconiments on the preparation Or the lURCH Comprehensive Environmental Res­ fiva.year reviews or other environmen­ I.MO B'usiness ponse, CompensatiOn, and Liability Act tal activities at Andrews AFB- may be ywine Rd, (CERCLA) Section 121 (c). The purpose directed to: Jhl. GROVV ofthe five-year review is to evaluate the 316th Airlift Wing Public Affairs performanCe ofprEwiouSly implemented Office (316 WGlPA) cleanup remedies to ensure these rema. 1535 Command Drive,: , t, 11:00am­ vvhen dies remain protective ofhumanhealtb _Andrews AFB, MD 20762-7002 _ Noon & and.the environment; the purpose is not Telephone: 301·981·7888 " you to reconsider these remedies. Should Fax: 301·981-4588 astor any remedy be found perfomrlng below EmaiJ.:316PAcomrel@andreWs:i1fmi1

I Pastor demgn.: expectations, the Air Force' will MORE INFQRMATION ' Christ advertise recommend improvements as part of Additional information about sites the fiva.Yem' ~The review~ also;, .4le1,~ded in "th:~ fiv&:year -~~,-~ provide a SlllIimai:Y ofilia 6.lrreht StatUs: mid-' other Andl-eWs AF'B :si~ is;a\rall­ ofon base CERCLA sites that do not yet able in theAdministrative.Reoord which in have-remedies in place. ' , is kept -at the Environmental Flight, - Twelve on baseenvironmentaIsiteB3466North Carolina Avenue, Andrews the-, will be included in the five year-review: AFB. For the convenience ofthe public, ProfessionaI .Fl'-02, Fire Tra.iniilg Area 1; Fl'-03, Fire a copy of the Administrativ.e Record is, Training Area 2; FT-04, Fire Training maintained in an Information' Directory Area 4; LF-05, Landfill 5; LF-06, RepOsitory located at: Landfill 6; LF-07, -Landfill 7; SI)..23, 'Prince George's County Memorial Sludge Disposal Area; ss.26,Hangar UlJrary-SUITatts.clinton Branch 15; 88-27, Former Dry Cleaner; 88.28, 9400 Piscataway Road , Building 1206; ST-I0, PD~80 Spill Site;· Clinton, MD 20735 and S'i'-14, East Side Gas Station.Ase~ . Phone 301~9200 Call arate five-~ review will be performed concurrently for SS·Ol·Brandywine Hours: -to Place DRMO, 'loCated approximately eight , Monday-Wednesday 10 am·9 pm Thursday-Friday 10 am~ pm. Your miles south-of AncirewsAFB. The Air Force plans to issue reports SatUrday 10am-5_ pin Ad

301 - 8EPREPARED fOR - 70-254 ]M jiIlJIjRd I'Mwtf' FREAK 'OUT WITH MASSAGE ENVY GIfT CARDS

It.ad.FortWashington, MD 2074~ ]!I The ~ev. Dr., Robert K Degges, Pastor. ~, '.; Worship SelVlce: 11 a.m., ...a

I rnili~arv The Gazette • 9030 Comprint Court, Gaithersburg, MD 20877 301-846-2100

This is to certify that the annexed advertisement of PUBLIC NOTICE AFB was published in the Clinton/Ft Washington Gazette newspapers, a weekly newspaper published in Prince Georges' County, Maryland. The ad appeared once a week for 1 week (s), before 1214/09.

Copy of Ad Attached Ad Order Number G538747 Publication Dates

1213/09 •

Gazette Legal Advertising Department • • PUBLIC NOTICE

The Air Forc~ is currently performing the first basewide five-year- review at Andrews Air Force Base (AFB), Prince George's COlJnty, Maryland, in, accordance with the requirements of the Comprehensive Environmental Response, Compensation, and Uability Act (CERCLA) Section 121 (c). The purpose of the five-year review is to evaluate the performance of previously implemented cleanup remedies to ensure .these remedies­ remain protective of human health and the-environment; the purpose is not to reconsider these remedies., Should any remedy be found performing below design expectations, the Air Force will recommend improvements as part" of the five-year review. The review will also provide,a summary of the current status of on base CERCLAsites that do not yet have remedies in place.

" Twelve on base environmental sites will be incl,uded in the five year review: FT-02, Fire Training Area 1; FT-03, Fire Training Area 2;FT-04,

I Fire Training Area 4; LF-05, Landfill 5; LF-06, Landfill 6; LF-07, Landfil,"7; ­ SD-23, Sludge Disposal Area; SS-26, Hanger 15; SS-27, Former DrY Cleaner; SS-28, Building 1206; ST-10, PD-680 Spill Site; and ST-14, East Side Gas Station; A separate five-year review will be performed concurrently for SS-01 Brandywine DRMO, located approximately eight" , miles south of Andrews AFB .

. The Air Force plans .to _issue reports_ ,detai'ling the five-year reviews in -August 2010. Following release oUhe reports, the Ai/" Force will also • issue a public notice and fact sheet. Questions or comments on the .preparation of the five-year reviews or other environm!;1ntal activities at A!1drew$ AFB may be ~irected to:

_316th Airlift Wing Public Affairs Office (31SWG/PA) , 1535 Command Drive ' Andrews AFB, MD 20762-7002 _Telephone: 361-981-7888 -Fax: 301-981-4588 Email: [email protected]

-MORE INFORMATION Additional information aboLJtsites included in the five-year review report ',and other Andrews AFB sites is available in the Administrative Record which is kept at the Environmental Flight; 3466 North Carolina Avenue, Andrews AFB. For the convenience of the public, a copy of the Administrative' Record ,is maintained in an Information RepOSitory -located ,at:'

Prince George's County Memorial-l:.ibrary-Sur~atts-Clinton Branch 9400 Piscataway RoaQ - Clinton, MD 20735 Phone (301) 868-9200' Hours: Monday-Wednesday 10 am-9 pm Thursday-Friday 10 am-6 pm Saturday 10 am-5 pm (12-3-09) , • G538747 > • "tI "tI m Z C >< a:I

•

• Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011) •

APPENDIXB FT-04 ARARS, MANN-KENDALL TEST RESULTS

•

• P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0 _ Deliverables\4.1 Reports\Final\AndrewsAFB _5-Yr Review _Revised March 201l.doc ­ • • • Table B-1 Summary of Potential Federal and State ARARs FT-04 Record of Decision, Andrews AFB; Maryland , Type Federal or State Statute, Regulation or of ARAR Guidance Summary of Requireineni ARAR Cate~ory Comments ,"~.;:; , , ., •••..<:" .' .': ".'.•... ",' ,,:,.;: , . ," .>.>~., ~.;"'. ~ ,"}.,,, • y~. ... ~ :~:.G; .. :>"~ ~.« \~. _":" · ...N·.·.'.«-.:,·,':'*" ,,",:, ...... ~~~":' -', .~=':.'" ,,:" '.,' ~;f: Water!: ;' ...... ~ .~ .--. , Safe Drinking Water Act, Public Law 93 - Provides Maximum Contaminant Levels (MCLs) RA Chemical Potential cleanup standards for groundwater at the site, 523,40 CFR Part 141· for the concentration of common contaminants in public drinking water supplies. Maryland Drinking Water Quality Standards, These rules parallel the Federal drinking water RA Chemical Potential cleanup standards for groundwater at the site; apply to the COMAR 2604.01.06, riJles. extent that they are more stringent than the federal standard. COMAR 26.04.01.07 Maryland Water Supply and Sewerage Prohibits the installation of individual wells for TBC Action, Drinking water supplied to Andrews AFB through public utility Planning, COMAR 2603.01.05 drinking water supply in areas already served by Location (WSSC). Installation of new wells for drinking water supply is adequate community drinking water supplies. therefore prohibited at any site at Andrews AFB, including FT-04. Maryland Water Pollution Regulations, Establishes criteria and standards for surface water RA Chemical May apply to treatment system injection material. COMAR26.08 and groundwater discharge limitations and policy for anti-degradation of waters of the State. Maryland issues a water quality certification for proposed discharges into waters of the state: certification ensures that water quality standards are not violated...... {",tv• " ~ _., •. h·, ~ •.• _. '" :J>'.f; . .:",,'",: ~ . ~ • h • ~.' ." ~ ••• <~'~!;-. ...::: ' ...... ,,,. .. Miscellaneous ...... " /,. ,.:" ;·j;:~;\'t~;~5.it.:<.:·: .. .. , . " Maryland Water Supply, Sewage Disposal, Provides specifications for well construction and RA Action Restoration of groundwater quality may be required. Also applies to and Solid Waste Regulations, abandonment. well construction and abandonment. COMAR 26.04.04.04, COMAR 26.04.04.07, COMAR 26.04.04.11 Maryland Board of Well Drillers Provides licensing requirements for persons A Action Applies to installation of new monitoring wells. Regulations, drilling and installing wells in the State. AssiJres COMAR 26.05.0 I, that monitoring wells are installed by qualified COMAR 26.05.02 well drillers.

A = Applicable Requiremeilt Action = Action-specific standard CpMAR 26 = Code of Maryland Regulations Title 26, Department of the Environment (January 7, 2005) RA = Relevant and Appropriate Requireinent Chemical = Chemical-specific standard TBC = To Be Considered Location = Location-specific standard Chemical-specific ARARs are regulatory health- or risk-associated numerical values that govern acceptable concentrations of a chemical in environmental media such as soil, water, or air. Action-specific ARARs are determined according to the specific technologies or activities taking place under an alternative. Location-specific ARARs are determined according to site-related characteristics such as geoiogy, floodplains, wetlands, sensitive ecosystems and habitats,and historic places,

Page I of I :MAROS Mal111-Kel1dall Statistics Summary .

Project: Andrews Air Force Base User Name: Washburn Location: Camp Springs State: Maryland

Time Period: 4/16/20041 to 9/17/20092 Consolidation Period: No Time Consolidation Consolidation Type: Median Duplicate Consolidation: Average ND Values: 1/2 Detection Limit .J Flag Values: Actual Value

All SourceJ Number of Number of Coefficient Mann·Kendall Confidence Samples Concentration nND" ? Well Tail Samples .Detects of Variation Statistic in Trend Trend

Arsenic

MW0302·Fr04 S 9 6 0.58 4 61.9% No NT MW0304-Fr04 T 9 4 0.50 0 46.0% No 5 MW0401-Fr04 T 9 5 0.65 -18 96.2% No 0 MW0402-FT04 T 7 6 0.66 ·3 61.4% No S MW0403-Fr04 T 7 .. 4 0.57 -6 76.4% No S MW0405-Fr04 ·T 4 0 0.17 3 72.9% Yes NO MW0501-Fr04 ·T 9 4 0.65 17 95.1% No MW8801-Fr04 T 8 1 0.58 15 95.8% No I • MW9302-Fr04 T 8 2 0.28 -7 76.4% No S MW9303-Fr04 T 8 2 0.48 15 95.8% No Benzene

MW0302-Fr04 S 9 8 1.82 14. 91.0% 'No PI MW0304-Fr04 T 9 4 2.93 -28 99.9% No 0 MW0401-Fr04 T 9 1 0.41 -1 50.0% No S MW0402~Fr04 T 7 7 1.36 -11 93.2% No PO MW0403-Fr04 T 7 4 .1.35 -10 90.7% No PO .MW0405-Fr04 T 4 4 0.75 2 62.5% No NT MW0501-Fr04 T 9 0 0.38 8 76.2% Yes NO MW8801-Fr04 T 8 0 0.17 0 45.2% Yes NO MW9302-Fr04 T 8 1 0.43 -9 83.2% No 5 MW9303-FT04 T 8 8 0.47 -5 68.3% No 5 Carbon tetrachloride

MW0302-FT04 S 9 2 2.96 -7 72.8% No NT· MW0304-Fr04 T 9 1 2.99 -8 76.2% No NT· MW0401-FT04 T 9 0 0.05 2 54.0% Yes NO MW0402-FT04 T 7 0 0.05 0 43.7% Yes NO. MW0403-FT04 T 7 1 0.90 -7 80.9% No 5, MW0405-FT04 t 4 0 0.06 -3 72.9% Yes NO, MW0501-Fr04 T 9 5. 1.16 -26 99.7% No 0 MW8801-FT04 T 8 5 1.63 1 50.0% No ·~NT MW9302-Fr04 T 8 0 0.06 0 45.2% Yes NO • MW9303-FT04 T 8 8 0.71 16 96.9% No I Manganese

MW0302-Fr04 S 9 9 0.39 14 91.0% No PI

MAROS Version 2,.2 2006, AFCEE Friday, January 29,2010 Page 1 of 2 Project: Andrews Air ForceBase User Name: Washburn Location: Camp Springs \ State: Maryland •

All Sourcel Number of Number of Coefficient Mann-Kendall . Confidence Samples Concentration Well Tail Samples Detects of Variation Statistic in Trend "NO" ? Trend

Manganese

MW0304-FT04 T 9 9 0.33 -14 91.0% No PD MW0401-FT04 T 8 8 0.24 -6 72.6% No S MW0402-FT04 T 7 7 0.26 16 99.0% No I MW0403-FT04 T 7 7 0.93 -3 61.4% No. S MW0405-FT04 T 4 4 0.11 0 37.5% No S MW0501-FT04 . T 8 8 0.28 -9 83.2% No S MW8801-FT04 T 7 7' 0.51 -17 99.5% No D MW9302-FT04 T 7 7 0.64 50.0% No NT MW9303-FT04 T 7 7 0.35 11 93.2% No PI

Note: Increasing (I); Probably Increasing (PI); Stable (5); Probably Decreasing (PO); Decreasing (D); No Trend (NT); Not Applicable (N/A)­ Due to insufficient Data « 4 sampling events); SourcefTaii (SfT)

The Number of Samples and Number of Detects shown above are post-consolidation values. •

• MAROS Version 2,.2 2006, AFCEE Friday, January 29,2010 Page 2 of2 •

):0 "'tI "'tI m 2 C X C")

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• Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting. Inc. Project Number 3350092494 (Revised March 2011) •

APPENDIXC ST-IO ARARS, MANN-KENDALL TEST RESULTS

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• P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0 _ Deliverables\4.1_ Reports\Final\AndrewsAFB _ 5-Yr Review_Revised March 201l.doc !

Table B·1 • Action·Specific• ARARs • ST·10 Record of Decision Andrews Air Force Base, Ma land ARAR Action Requirement Prerequisite Citation Determination Comments

Discharge to porn Pretreatment standards. Controllhe introduction of pollutants into POTWs Discharge to POTW. 40 CFR 403.5 Potentially applicable Remedial actions at ST-10 may include the discharge of so as to: prevent interference with the operation of a POTW; prevent pass treated groundwater to a POTW. through of pollutants through a treatment works; and improve opportunities to recyde and redaim municipal and industrial. wastewater and sludges.

:.:ons thai affect Promulgates National Primary Drinking Water Standard Maximum Actions that affect drinking water supply 40 CFR 141 Relevant and approriate MCls are ARARs for remedial actions at ST-l0 Site that inking water Contaminant Levels (Mels) affect groundwater. ~ pply

State Action-Specific ARARs

Quality of Drinking MCls of inorganic and organic chemicals in drinking water Actions thai affect drinking water supply COMAR 26.04.01.06 and .07 Applicable State Mels are ARARs for remedial actions at ST-l0 Site. Waler

nslallation of new Provides criteria for installation of individual water supply and sewerage An individual water supply or individual sewerage COMAR 26.03.01.05 Applicable Installation of any water supply 'NEllis at ST-10 will not be water supply wells systems. system may not be permitted to be installed where permiHed by the State because the existence of an an adequate community water or sewerage facility adequate public water supply and sewerage systems. is available.

Groundwater Groundwatrr quality standards for aquifers in the State and protection of Actions that affect groundwater quality and COMAR 26.08.02.09 and Applicable Remedial actions at ST-10 will affect the groundwater Quality Standards the aquifers. degradation of waters of the State 26.08.02.04 quality. .

r"'ell Construction To ensure a dean and adequate supply of underground drinking water, the Drilling and installation of groundwater monitoring COMAR 26.04.04.02, Applicable The remedial action at ST-10 may include the installation of ~nd Abandonment State carries out programs to prevent contamination of aquifers from. 'M!lIs. 26.04.04.07,26.04.04.11 groundwater monitoring wells. improper ~II construction and well abandonment.. )3Oiirdof w.n:tirine... Drilling and Establishes licensing requirements for persons drilling and installing wells Drilling and installation of ~lIs. COMAR 26.05.01,26.05.02 - Potentially applicable The remedial action at ST-10 may indude the installation of Installation of Wells in the State, to ensure that monitoring wells are installed by ·qualified well General Regulations - Well groundwater monitoring 'M!lIs. drillers. Drillers

Statutes and policies. and their citations, are provided as headings to identify general categories of potential ARARs. Specific potential ARARs are addressed in the table below each heading. ~cronyms used in the table: OSHA - Occupational Safety and Health Administration ~PEN - Air Pollution Emission Notice. PCBs - Polychlorinated Biphenyls ~RAR - Applicable or relevant and appropriate requirement. POTW· Publidy o'NJ'led treatment works. CM - Clean Air Act. ppm - Parts per million. CAMU - Correction action management unit. ppmw - Parts per million by \Wight. ReRA - Resource Conservation and Recovery Act. RA - Relevant and approp.riale. FR - Code for Federal Regulations. RACT - Reasonably Available Control Technology.

WA - Clean Water Act ..J CERCLA - ComprehenSive Environmental Response, Compensation, and EPA - U.S. Environmental Protection Agency. Uability Act. LAER - lowest achievable emission rate. SDWA - Safe Drinking Water Act. MCls - Maximum contaminant levels. SIP - State Implementation Plan NMQS - National Ambient Air Quality Standards (primary and secondary). TSCA - Toxic Substances Control Act NESHAP - Nationat emiSSion standards for hazardous air pollutants. USC - United States Code. NCP - National Contingency Plan. TSCA - Toxic Substances Control Act NPDES - National Pollutant discharge elimination system. .VOCs - Volatile Organic Compounds. TABLE B-2 Chemical-Specific ARARs and TBCs ST-10 Record of Decision Andrews Air Force Base, Maryland· •

ARAR - 2004 Federal and State COC MCl (ug/l) TBC (ug/l)

!Arsenic 10 - Benzene 5 - NA 18.2" Naphthalene

NA - Not applicable. An MCl does not exist for these constituents. Source: 2004 Edition of the Drinking Water Standards and Health Advisories (USEPA 822-R-04-00S) "Cleanup criterion is a site-specific risk-based standard calculated using guidance developed by USEPA Region III

•

• ~ . ~iVIAROS Mal1l1-Kendall Statistics SUlllil1ary

Project: Andrews Air Force Base User Name: Washburn Location: Camp Springs State: Maryland

Time Period: 3127/2001 1 to· 9/16/2009 1 Consolidation Period: No Time Consolidation Consolidation Type: Median Duplicate Consolidation: Average . ND Values: 1/2 Detection Limit J Flag Values: Actual Value

All Sourcel Number of Number of Coefficient Mann-Kendall Confidence Samples Concentration· Well Tail Samples Detects of Variation Statistic in Trend "Non? Trend

Arsenic ,dissolved

MW02-ST10 S 7 7 0.27 11 93.2% No PI MW03-ST10 T 8 8 0.38 2 54.8% . No NT MW04-ST10 . T 8 8 0.27 5 68.3% No . NT Note: Increasing (I); Probably Increasing (PI); Stable (S); Probably Decreasing (PD); D.ecreaslng (D); No Trend (NT); Not App!lcaple (N1A)- Due to insufficient Data « 4 sampling events); SourcEilTall (SIT) . • . . '. . . '. The Number of Samples and Number of Detects shown aboVe are post-consolidation values ..

•

MAROS Version 2,.2 2006, AFCEE Friday, January 29,2010 Page 1 of 1 MAROS Mal111-Kelldall Statistics SU1TIlnary :-

Project: Andrews Air Force Base User Name: Washbum Location: Camp Springs State: Maryland

Time Period: 3127/2001.1 to 9/16/2009 1 Consolidation Period: No Time Consolidation Consolidation Type: Median Duplicate 'Consolidation: Average NO Values: 1/2 Detection Limit J Flag Values: Actual Value

All Sourcel . Number of Number of Coefficient Mann-Kendall Confidence Samples Concentration Well Tail Sa~ples Detects of Variation Statistic in Trend "NO"? Trend

Arsenic ,total

MW02-ST10 S 10 10 0.19 15 89.2% No NT MW03·ST10 T. 11 11 0.31 13 82.1% No NT MW04-ST10 T 11 11 0.26 19 91.8% No PI Note: Increasing (I); Probably Increasing (PI);.Stabla (S); Probably Decreasing (PC); Decreasing (0); No Trend (NT); Not Applicable (NfA)­ Due to insufficient Data « 4 sampling events); SourceITall (SIT) The Number of Samples a.rid Number of Detects shown above are post-consolldation·values. '.

• MAROS Version 2,.2 2006, AFCEE Friday, January 29,2010 Page 1 of 1 l> "'tI "'tI m Z C >< C • Joint Base Andrews - First Five- Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 201 I) •

APPENDIXD ST-14 ARARS, MANN-KENDALL TEST RESULTS, REGRESSION PLOTS

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• P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0 _ Deliverables\4.1_ Reports\Final\AndrewsAFB _ 5-Yr Review_Revised March 20 II.doc TA8LE 8-1 • Synopsis of State Action-Specific Applicable or Relevant• and Appropriate Requirements for the Selected Remedy • ST-14 Record of Decision Andrews Air Force 8ase, Maryland

REGULATORY CHEMICAL CONSIDERATION IN THE REMEDIAL REQUIREMENT STATUS REQUIREMENT SYNOPSIS AUTHORITY MEDIUM RESPONSE PROCESS State Groundwater Groundwater Quality Applicable Maryland Antidegradation Policy: Remedial action at ST-14 will Standards COMAR actions cannot degrade state require discharges to the 26.0S.02.04(A) thru waters. Section 09(8) identifies groundwater, affecting the (C) and Maryland groundwater groundwater quality. 26.0S.02.09(8) thru classifications. Section 09(C) and (D) (D) regulate discharges to the und~rground of the State. State Groundwater Well Construction and Applicable To ensure a clean and adequate The remedial action at ST-14 may Abandonment supply of underground drinking include the installation of COMAR 26.04.04.02, water; the State carries out groundwater monitoring wells. 26.04.04.07, programs to prevent 26.04.04.11 contamination of aquifers from improper well construction and well abandonment. State Groundwater Drilling and installation Applicable Establishes licensing requirement The remedial action at ST-14 may of wells COMAR for persons drilling and installing include the installation of 26.05.01.01 thru .OS wells in the State, to ensure that groundwater monitoring wells. monitoring wells are installed by qualified well drillers. State Soil and Sampling and Applicable Establishes specific analytical The remedial action at ST-14 will Groundwater Analysis CO MAR requirements for testing and generate soil and groundwater 26.13.03.02 evaluating solid, hazardous, and IDW from monitoring well water wastes. installation and groundwater sampling. Notes: CFR = Code of Federal Regulations COMAR = Code of Maryland Regulations lOW = Investigation-Derived Waste TABLE B-2 Synopsis of Federal and State Chemical-Specific Applicable or Relevant and Appropriate Requirements for the Selected Remedy ST-14 Record of Decision Andrews Air Force Base, Maryiand

REGULATORY CHEMICAL CONSIDERATION IN T~HE REMEDIAL REQUIREMENT StATUS REQUIREMENT SYNOPSIS AUTHORITY MEDIUM . RESPONSE PROCESS Federal Groundwater Safe Drinking Water Applicable The National Primary Drinking Active treatment will be conducted Act, National Water Regulations establish MCLs to meet MCLs in groundwater. Primary Drinking for common organis; and inorganic Monitoring will be performed to Water Regulations, contaminants. MCLs specify the measure changes in contaminant Maximum maximlim permissible concentra­ concentrations or migration. Contaminant Levels tions of contaminants in public MCLs Wilroe achieved through (MCLs) [40 CFR drinking water supplies. MCLs are active treatment and natural 141.61(a)(1) thru (3) federally enforceable standards attenuation processes. and (5).] based in part on the availability and cost of treatment techniques.

State Drinking Water Drinking Water Applicable MCLs for organic chemicals in State MCLs are ARARs for Standards COMAR drinking water remedial actions at ST-14. 26.04.01.07(0)(1 ) thnj (3) and (5) CFR - Code of Federal Regulations COMAR = Code of Maryland Regulations MCLs =Maximum Contaminant Levels

• • • :'~MAROS Mal111-Kendall Statistics Sumlnary. "

Project: Andrews AFS User Name: Sinks

Location: Camp Springs State: Maryland,

Time Period: 3/1/2006 to 1011/2009 Consolidation Period: No Time Consolidation Consolidation Type: Median Duplicate Consolidation: Average NO Values: 112 Detection Limit J Flag Values: Actual Value

All Source! Number of' Number of Coefficient Mann-Kendall Confidence Samples Concentration Well Tail Samples Detects of Variation Statistic In Trend '''NO'' ? Trend

TRICHLOROETHYLENE (TCE)

MW03-3471 , T 8 0.19 50.0% No NT MW10-ST14 T 8 1.50 -5 68.3% No NT MW11-ST14 S' 13 13 1.34 -68 100.0% No o MW12-ST14 S 9 9 0.84 -25 99.6% No, o MW13-ST14 S 13 13 1.76' -56 100.0% No o MW15-ST14 S 13 13 1.55 -54 100.0% No o MW16-ST14 T 9 9 0.27 -2 54.0% No S MW17-ST14 T 9 5 1.31 "19 97.0% No o Mw18-ST14 T 4 o 0.00 o 37.5% Yes NO • MW19-ST14 S 9 9 0.94 -32 100.0% No o MW20-ST14 T 4 o 0.00 o 37~5% Yes NO MW21-ST14 T 2 o 0.00 o , 0.0% Yes NO MW22-ST14 T 6 2 0.26 -3 64.0% No 5 MW23-ST14 T 9 9 1.00 -18 96.2% No o MW24-ST14 T 9 9 0.43 -28 99.9% ' No o MW25-ST14 T 6 0.21 3 64.0% No NT MW26-ST14 T 6 0.15 3 64.0% No NT MW27-ST14 T 8 8 0.56' 4 64.0% No NT MW29-ST14 T 5 o 0.00 o 40.8% Yes NO MW30-ST14 T 8 o 0.00 o 45.2% Yes NO MW31-ST14 T' 8 8 0.66 16 96.9% No MW32-ST14 T 9 7 0.72 17 95.1% No I ,MW33-ST14 T 9 9 0.22 -18 96.2% No o MW34-ST14 T 9 8 0.64 -29 '100.0% No o MW35-ST14 T 9 9 0.40 10 82.1% No NT MW37-ST14, T 9 9 0.39 24 99.4% No I MW38-ST14 T 4 o 0.00 o 37.5% Yes NO ST14-MW01 T 8 8 0.53 2 54.8% No NT ST14-MW02 T 8 7 0,87, 10 86.2% No NT ST14-MW03 T 9 9 0.11 -10 82.1% No S ST14-MW04 T 9 9 0.99 2 54.0% No NT ST14-MW05 T 9 9 0.50 16 94.0% No PI ST14-MW06 T 8 8 0.72 -5 68.3% No 5 ST14-MW07 T 9 9 1.08 6 69.4% No NT ST14-MW08 T 8 7 1.85 -16 96.9% No o • ST14-MW09 T 9 4 0.44 -12 87.0% No 5 MAROS Version 2,.2 2006, AFCEE ' Wednesday, January 27, 2010 Page 1 of2 Project: Andrews AFB User Name: Binks Location: Camp Springs State: Maryland •

All Sourcel Number of .Number of Coefficient Mann-Kendall Confidence ·Samples Concentration Well Tail Samples Detects of Variation Statistic In Trend "NO" ? Trend

TRICHLOROETHYLENE (TCE)

Note: Increasing (I): Probably Increasing (PI); Stable (S); Probably Decreasing (PD);Decreasing (D); No Trend (NT); Not Applicable (N/A)­ Due to insufficient Data « 4 sampling events); SourcelTaii (Srr)

The Number of Samples and Number of Detects shown above are post-consolidation values.

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MAROS Version 2,.2 2006, AFCEE • . Wednesday, January 27,2010 Page 20f2 , - - -, ' )MAROS 'Manll-Keridall Statistics Summary . ­ ./. ~- , - . . -

Project: Andrews AFB User Name: Binks Location: Camp Springs State: Maryland

Time Period: 3/1/2006 to 1011/2009 Consolidation Period: No Time Consolidation Consolidation Type: Median Duplicate Consolidation: Avera.ge NO Values: 1/2 Detection Limit J Flag Values: Actual Value

All Source! Number of Number of Coefficient Mann·Kendall ,Confidence Samples Concentration Well Tail Samples Detects of Variation Statistic In Trend "NO"? Trend

CARBON TETRACHLORIDE

MW03-3471 T 8 o 0.00 o 45.2% Yes ND MW10-ST14 T 8 o 1.SO -5 68.3% Yes ND MW11-ST14 T 13 1 1.2" ·1 SO.O% No NT MW12-ST14 T 9 o 0.85 -6 69.4% Yes ND MW13-ST14 T 13 o 0.33 ·10 70.5% Yes ND MW15-ST14 T 13 o 0.26 -4 57.1% Yes' ND MW16-ST14 T 9 o 0.00 o 46.0% Yes ND MW17-ST14 T 9, o 0.83 13 89.0% Yes ND MW18-ST14 T 4 o 0.00 o 37.5% Yes ND • MW19-ST14 T 9 2 0.69 8 76.2% No NT MW20-ST14 T 4 o 0.00 o 37.5% Yes ND MW21-ST14 T 2 o 0.00 o 0.0% Yes ND MW22-ST14 S 6 o 0.00 o 42.3% Yes ND MW23-ST14 S 9 1 2~59 -8 76.2% No NT MW24-ST14 T 9 9 0.52 '·10 82.1% No S MW25-ST14 T 6 o 0.00 o 42.3% Yes ND MW26-ST14 T 6 o 0.00 o 42.3% Yes ND MW27-ST14 T 8 8 0.27 -4 64.0~ No S MW29-ST14 T 5 o 0.00 o 40:8% Yes ND MW30-ST14 T 8 o 0.00 O· 45.2% Yes ND MW31-ST14 T B o 0.00 o 45.2% Yes ND MW32-ST14 T 9 8 0.52 ·16 94.0% No PD MW33-ST14 T 9 o 0.00 a 46.0% Yes ND MW34-ST14 T 9 o 0.00 o '46.0% Yes ND MW35-ST14 T 9 o 0.00 o 46.0% Yes ND MW37-ST14 T 9 o 0.73 21 98.3% Yes ND MW38-ST14 T 4 o 0.00 o 37.5% Yes ND, ST14-MW01 T 8 8 0.15 3 59.4% No NT ST14-MW02 T 8 o 0.31 .7 76.4% Yes ND STl4-MW03 T 9 5 0.43 -16 94.0% No PD STl4-MW04 T 9 0:86 3 58.0% 'No NT STl4-MW05 T 9 9 0.55 12 87.0% No NT STl4-MW06 T 8 1 0.15 50.0% No NT STl4-MW07 T 9 5 0.69 -19 97.0% No D STl4-MWQB T 8 1 0.15 7 76.4% No NT • ST14-MW09 T 9 o 0.00 o 46.0% Yes ND MAROS Version 2,.2 2006, AFCEE Wednesday, January 27, 2010 Page 1 of2 Project: Andrews AFB User Name: Binks Location: Camp Springs State: Maryland ".

All Sourcel Number of Number of Coefficient Mann-Kendall Confidence -Samples Concentration Well Tall Samples Detects of Variation Statistic In Trend "NO"? Trend

CARBON TETRACHLORIDE

Note: Increasing (I): Probably Increasing (PI): Stable (S): Probably Decreasing (PO): Decreasing (D); No Trend (NT): Not Applicable (N/A)­ Due to insufficient Data « 4 sampling events); SourcelTaii (SIT)

The Number of Samples and Number of Detects shown above are post-consolidation values.

•

MAROS Version 2,.22006, AFCEE • Wednesday, January 27, 2010 Page 2 of2 . . -~MAROS Mann-Kel1dall Statistics Sumniary .' ..

Project: Andrews AFS User Name: Sinks Location: Camp Springs State: Maryland

Time Period: 3/1/2006 to 1011/2009 Consolidation Period: No Time Consolidation Consolidation Type: Median Duplicate Consolidation: Average NO Values: 112 Detection Limit J Flag Values: ActualValue

All Sourcel Number of Number of Coefficient Mann-Kendall Confidence Samples Concentration Well Tail Samples Detects of Variation Statistic in Trend "NO" ? . Trend BENZENE

MW03-3471 T 8 8 0.36 10 86.2% No NT MW10-ST14 S 8 8 0.99 -10 86.2% No 5 MW11-ST14 T 13 8 0.98 41 99.4% No MW12-ST14 T. 9 1 0.85 ·11 84.6% No S MW13-ST14 T 13 8 0.30 -8 66.2% No S MW15-ST14 T 13 ·4 1.69 22 69.8% 'No NT MW16-ST14 T 9 9 . 0.32 o 46.0% No S MW17-ST14 T 9 8 2.07 -24 99.4% No D MW18-ST14 T 4 o 0.00 o 37.5% Yes NO • MW19-ST14 T 9 3 0.58 10 82.1% No NT MW20-ST14 T 4 0.19 ·3 72.9% No S MW21-ST14 T 2 o 0.00 o 0.0% Yes ND. MW22-ST14 T 6 o 0.00 o 42.3% Yes NO MW23-ST14 T 9 o 0.00 o 46.0% Yes NO MW24-ST14 T 9 o 0.00 o 46.0% Yes NO MW25-ST14 T 6 o 0.00 o 42.3% Yes NO MW26-ST14 T 6 o 0.00 o 42.3% Yes NO MW27-ST14 T 8 o 0.00 o ·45.2% Yes NO MW29-ST14 T 5 o 0.00 o 40.8% Yes NO MW30-ST14 T 8 o 0.00 o 45.2% Yes NO MW31-ST14 T 8 o 0.00 o 45.2% Yes NO MW32-ST14 T 9 2 0.61 21 98.3% No I MW33·ST14 T 9 o 0.00 .0 46.0% Yes' NO MW34-ST14 T 9 9 0.18 -14 91.0% No PO MW35-ST14 T 9 o 0.00 o 46.0% Yes NO MW37-ST14 T 9 5 0.50 22 98.8% No I MW38-ST14 T 4 o 0.00 o 37.5% Yes NO ST14-MW01 T 8 o 0.00 o 45.2% Yes NO ST14-MW02 T 8 7 0.90 8 80.1% No NT ST14-MW03 T 9 9 0.49 -34 100.0% No D ST14·MW04 S 9 9 0.27 -28 99.9% No o ST14-MW05 T 9 9 0.32 -4 61.9% No S ST14-MW06 T 8 1 0.07 3 59.4% No NT ST14-MW07 T 9 4 0.79 -2 54.0% No S ST14-MW08 T 8 1 p.10 7 76.4% No NT ST14-MW09 T 9 o 0.00 o 46.0% Yes NO • ETHYLBENZENE MAROS Version 2,.2 2006, AFCEE Wednesday, January 27,2010 Page 1 of4 Project: Andrews AFB User Name: Binks' Location: Camp Springs State: Maryland •

All Sourcel Number of Number of Coefficient Mann-Kendall Confidence Samples Concentration Well Tail Samples Detects of Variation Statistic In Trend "NO"? Trend ETHVLBENZENE

MW03-3471 T 6 8 0.55 -12 91.1% No PO MW10-ST14 S 8 8 1.19 -8 80.1% No NT MW11-ST14 T 13 o 1.21 7 64.0% Yes NO MW12-ST14 T 9 o 0.85 -6 69.4% Yes NO MW13-ST14 T 13 o 0.33 -10 70.5% Yes ND MW15-ST14 T 13 o 0.26 -4 57.1% Yes ND MW16-ST14 T 9 o 0.00 o 46.0% Yes ND MW17-ST14 T 9 3 1.95 13 ·89.0% No NT MW16-ST14 T 4 o 0.00 o 37.5% Yes ND MW19-ST14 T 9 o 0:68 9 79.2% Yes ND MW20-$T14 T 4 a 0.00 o 37.5% Yes' ND MW21-ST14 T 2 a 0.00 o 0.0% Yes ND MW22-ST14 T 6 o 0.00 o 42.3% Yes ND MW23-ST14 T 9 o 0.00 o 46.0% Yes NO MW24-ST14 T 9 o 0.00 o 46.0% Ves ND MW25-ST14 T 6 .0 0.00 o 42.3% Yes ND MW26-ST14 T 6 o 0.00 o 42.3% Yes ND' MW27-ST14 T 6 o 0.00 o 45.2% Yes NO MW29-ST14 T 5 o 0.00 o 40.8% Ves NO MW30-ST14 T 8 o 0.00 o 45.2% Ves NO MW31-ST14 T 6 o 0.00 o 45.2% Yes ND MW32-ST14 T 9 o 0.63 17 95.1% Ves NO MW33-ST14 T 9 0.00 46.0% Yes NO • o o MW34-ST14 T 9 o 0.00 o 46.0% Ves NO MW35-ST14 T 9 o 0.00 o 46.0% Ves NO MW37-ST14 T 9 o 0.73 21 96.3% Ves NO MW36-ST14 T 4 o 0.00 o .37.5% Yes NO ST14-MW01 T 8 o 0.00 o 45.2% Ves ND ST14-MW02 T 8 6 1.20 7 76.4% No NT ST14-MW03 T 9 9 0.45 -26 99.7% No o ST14-MW04 S 9 9 0.16 -19 97.0% No D ST14-MW05 9 0.28 69.4% .' T 9 6 No NT ST14-MW06 T 6 o 0.00 o 45.2% Yes NO ST14-MW07 T 9 o 0.93 6 69.4% Yes NO ST14-MW06 T 6 o 0.00 o 45.2% Yes NO ST14-MW09 . T' 9 o 0.00 o 46.0% Ves NO TOLUENE

MW03-3471 T 6 2 0.20 -1 SO.O% No S MW10-ST14 S 6 8 1.01 -8 80.1% No NT MW11-ST14 T 13 5 1.34 5 59.4% No NT MW12~ST14 T 9 o 0.85 -6 69.4% Yes NO MW13-ST14 T 13 o 0.33 -10 70~5% Yes NO MW15-ST14 T 13 o 0.26 -4 57.1% Yes NO MW1.6-ST14 T 9 o 0.00 o 46.0% Yes NO MW17-ST14 T 9 2 1.51 14 91.0% No PI MW18-ST14 T 4 o 0.00 o 37.5% Yes ND . MW19-ST14 T 9 o 0.68 9 79.2% Yes ND MW20-ST14 T '4 o 0.00 o 37.5% Yes NO MW21-ST14 T 2 o 0.00 o 0.0% Yes ND • MAROS Version 2,.2 2006, AFCEE Wednesday. January 27,2010 Page 2 of4 erOject: Andrews AFB User Name: Binks

Location: Camp Springs State: Maryland

All Source! .Number of Number of Coefficient Mann-Kendall Confidence Samples Concentration Well Tall Samples Detects of Variation Statistic In Trend "NO"? Trend

TOLUENE

MW22-ST14 T 6 o 0.00 o -42.3% Yes NO Mw23-ST14 T 9 0.10 8 76.2% No NT MW24-ST14 T 9 o 0.00 o 46.0% Yes ND MW25-ST14 T 6 0.06 . -1 50.0% No 5 MW26-ST14 T 6 o 0.00 o 42.3% Yes ND MW27-ST14 T 8 o 0.00 o 45.2% Yes ND MW29-ST14 T 5 o 0.00 o 40.8% Yes ND MW30-ST14 T 8 o 0.00 o 45.2% Yes, ND MW31-ST14 . T 8 o 0.00 o 45.2% Yes ND MW32-ST14 'T 9 o 0.63 17 95.1% Yes ND MW33-ST14 T 9 o 0.00 o 46.0% Yes ND MW34-ST14 T 9 o 0.00 o 46.0% Yes ND MW35-ST14 T 9 '1 0.17 8 76.2% No NT MW37-ST14 T 9 o 0.73 21 98.3% Yes ND MW38-ST14 T 4 o '0.00 o 37.5% Yes .ND ST14-MW01 T 8 o 0.00 o 45.2"10 Yes ND ST14-MW02 T 8 6 1.12 17 97.7% No I ST14-MW03 T 9 9 0.61 -24 99.4% No D ST14-MW04 5 9 9 0.35 -20 97.8% No D ST14-MW05 T 9 9 0.33 ,-8 76.2% No S ST14-MW06 T 8 0.61 -3 59.4% No 5 • ST14-MW07 T 9 o 0.93 6 69.4% Yes ND ST14-MW08 T 8 o 0.00 o 45.2% Yes ND ST14-MW09 T 9 o 0.00 o 46.0%' Yes ND XYLENES, TOTAL

MW03-3471 T 8 3 0.28 -4 64.0% No ,5 MW10-ST14 S 8 8 0.93 "12 91.1% No PD MW11-ST14 T 13 o 1.21 7 64.0% Yes ND MW12-ST14 T, 9 o 0.85 -6 69.4% . Yes ND MW13-ST14 T 13 o 0.33 -10 70.5% Yes ND MW15-ST14 T 13 o 0.26 -4 57.1% Yes ND MW16-ST14 T 9 o . 0.00 o 46.0% Yes ND MW17-ST14 T 9 3 0.81 10 82:1% No NT MW18-ST14 T 4 o 0.00 o 37.5% Yes ND MW19-ST14 T 9 o 0.68 9 79.2% Yes ND MW20-ST14 T 4 o 0.00 o 37.5% Yes ND MW21-ST14 T 2 o 0.00 o 0.0% Yes ND MW22-ST14 T 6 o 0.00 o 42.3% Yes ND MW23-ST14 T 9 o 0.00 o 46.0% Yes ND MW24-ST14 T 9 1 0.55 o 46.0% No S MW25-ST14 T 6 1 0.22 -1 50.0% No S MW26-ST14 T 6 o 0.00 o 42.3% Yes NO MW27-ST14 T 8 o 0.00 o 45.2% Yes NO MW29-ST14 T 5 o '0.00 o 40.8% Yes NO MW30-ST14 T 8 o 0.00 o 45.2% Yes NO MW31-ST14 T 8 o 0.00 o 45.2% Yes NO MW32-ST14 T 9 o 0.63 17 95.1% Yes NO MW33-ST14 T 9 o 0.00 o 46.0% Yes NO • MW34-ST14 T 9 0.55 o 46.0% No 5 MAROS Version 2,.2 2006, AFCEE Wednesday. January 27, 2010 Page 3 of4 Project: Andrews AFB User Name: Binks Location: Camp Springs State: Maryland •

All Source! Number of Number of Coefficient Mann-Kendall Confidence Samples Concentration Well - Tall Samples Detects -of Variation Statistic in Trend "ND" ? Trend

XYLENES,TOTAL

MW35-ST14 T 9 0 0.00 0 46.0% Yes ND MW37-ST14 T 9 1 0.73 23 99.1% No I MW38-ST14 T 4 0 0.00 0 37.5% Yes NO ST14-MW01 T 8 0.57 -1 50.0% No S ST14-MW02 T 8 6 1.15 9 83.2% No NT ST14-MW03 T 9 6 0.83 -5 65.7% No S ST14-MW04 S 9 9 0.21 - -10 82;1% No S ST14-MW05 T 9 9 0.30 12 87.0% No NT ST14-Mw06 T 8 0.40 -3 59.4% No S ST14-MW07 T 9 0 0.93 -6 69.4% Yes NO ST14-MW08 T 8 0 0.00 0 45.2% Yes NO ST14-MW09 T 9 1 0.00 0 46.0% No S

Note: Increasing (I); Probably Increasing (PI); Stable (8); Probably Decreasing (PO); Decreasing (D); No Trend (NT); Not Applicable (N/A)­ Due to Insufficient Data « 4 sampling events); 80urcefTall (8fT)

The Number of Samples and Number of Detects shown above are post-consolidation values. •

MAROS Version AFCEE • 2,.2 2006, Wednesday, January 27,2010 Page 4 ,?f4 ST-14 Trichloroethene• Regression Analysis •

MW12 Days Cone 03/02/06 Mar-06 MW12 0 1180 1400 10/22/07 Nov-07 MW12 590 1200 01/22/08 Jan-08 MW12 680 505 1000 03/25/08 Apr-08 MW12 743 505 800 06/11/08 Jul-08 MW12 819 457 600 ...... Series1 10103/08 Oct-08 MW12 931 82.9 400 --linear (Series1) 01 /08/09 Jan-09 MW12 1026 237 200 04/14/09 Apr-09 MW12 1122 186 0 07/29/09 Jul-09 MW12 1227 233 0 500 1000 1500 10/13/09 Oct-09 MW12 1301 182 slope = -0 .794929 days = 1478 years = 4.0

MW16 Days Cone 03/01/06 Mar-06 MW16 0 64.8 100 11/08/07 Nov-07 MW16 607 80 01/01/08 Jan-08 MW16 660 27.5 03/26/08 Apr-08 MW16 745 88.3 60 ...... series1 06/16/08 Jul-08 MW16 825 86.5 40 10/03/08 Oct-08 MW16 932 68.8 --linear (series1) 20 01/09/09 Jan-09 MW16 1028 59.7 04/07/09 Apr-09 MW16 1116 75.4 0 07/23/09 Jul-09 MW16 1222 67.3 0 500 1000 1500 10/12/09 Oct-09 MW16 1301 65.2 slope = 0.005768 days = not calculated years = not calculated

1 of 2

P:\Projects\Andrews AFB\Five-year reviews\4.0_Deliverables\4.1_Reports\Draft\Appendix D ST-14\ST14 regression .xls 2/18/2010 ST-14 Trichloroethene Regression Analysis

MW24 Days Cone 03/02/06 Mar-06 MW24 0 64.1 70 ~ 10/22/07 Nov-07 MW24 590 60 01/22/08 Jan-08 MW24 680 31 .8 50 03/25/08 Apr-08 MW24 743 29.4 40 ------~ 06/09/08 Jul-08 MW24 817 35.1 30 ----- ... -+-Series1 .... ~~ 10/02/08 Oct-08 MW24 930 25.2 20 ..... --Linear (Series1) 01/07/09 Jan-09 MW24 1025 26.6 10 04/09/09 Apr-09 MW24 1117 26.2 0 07/23/09 Jul-09 MW24 1221 22 .7 o 500 1000 1S00 10/14/09 Oct-09 MW24 1302 .18.4 slope = -0.032663 days = 1809 years = 5.0

MW33 Days Cone 02/28/06 Mar-06 MW33 0 32.2 35 ,------­ 11/01/07 Nov-07 MW33 601 30 ~-=~------01/01/08 Jan-08 MW33 661 24.2 25 +------~~~K_------~---- 03/24/08 Apr-08 MW33 744 22.4 20 +------~~~~~-,---- 06/13/08 Jul-08 MW33 823 19 15 +------~~--~~-- -+-Series1 10/06/08 Oct-08 MW33 936 21.2 10 +------Linea r (Series1) 01/08/09 Jan-09 MW33 1028 16.4 5 +------­ 04/09/09 Apr-09 MW33 1119 21 .6 o 07/29/09 Jul-09 MW33 1229 22.8 o 500 1000 1500 10/12/09 Oct-09 MW33 1302 16 slope = -0.010267 days = 2649 years = 7.3

Prepared by SWR 01/14/2010 Checked by

2 of 2 P:\Projects\Andrews AFB\Five-year reviews\4.0_Deliverables\4.1_Reports\Draft\Appendix D ST-14\ST1;..a:.ession.xls 2/18/2010. • • Plot of• Chlorinated Ethene Molar Concentrations vs. Time • MW11-ST14 Andrews Air Force Base, Maryland

Mass Concentration, ug/L Calculated Molar Concentration, mmollL Date PCE TCE c-1,2-DCE t-1,2-DCE VC PCE TCE c-1,2-DCE t-1,2-DCE VC Total Mar-06 624 28.8 1 1 0.000 4.749 0.297 0.010 0.016 5.073 Jun-06 545 22.3 1 1 0.000 4.148 0.230 0.010 0.016 4.404 Aug-06 209 8.41 1 1 0.000 1.591 0.087 0.010 0.016 1.704 Oct-06 378 15.2 1 1 0.000 2.877 0.157 0.010 0.016 3.060 Nov-07 32.1 3.12 5 5 0.000 0.244 0.032 0.052 0.080 0.408 Jan-08 145 9.95 1 1.14 0.000 1.104 0.103 0.010 0.018 1.235 Apr-08 67.9 6.26 2 0.71 0.000 0.517 0.065 0.021 0.011 0.613 Jul-08 77.5 35.1 2 1.14 0.000 0.590 0.362 0.021 0.018 0.991 Oct-08 14.8 152 2.7 3.07 0.000 0.113 1.568 0.028 0.049 1.758 Jan-09 9.81 140 0.359 4.92 0.000 0.075 1.444 0.004 0.079 1.601 Apr-09 4.3 123 10 10 0.000 0.033 1.269 0.103 0.160 1.565 Jul-09 1.2 86.9 0.372 2.68 0.000 0.009 0.896 0.004 0.043 0.952 Oct-09 0.625 137 0.639 16.9 0.000 0.005 1.413 0.007 0.270 1.695 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 * Values less than reporting limit = reporting limit Plot of Chlorinated Ethene Molar Concentrations vs. Time 6.000

5.000

4.000 -+-PCE _ TCE -l 3.000 C/) .....c-l,2-DCE "0 2.000 E ~ t - l , 2-DCE E 1.000 ~ VC

0.000

P:\Projects\Andrews AFB Environment al\Five-year reviews\4.0_Deliverables\4.1_Reports\Draft\Appendix 0 5T-14 ARARs, MK Test Results, Regression Plots\files\Ceth vs time MWll 4/26/2010 Plot of Chlorinated Ethene Molar Concentrations vs. Time MW13-ST14 Andrews Air Force Base, Maryland

Mass Concentration, ug/L Calculated Molar Concentration, mmol/L Date PCE TCE c-1,2-DCE t-1,2-DCE VC PCE TCE c-1,2-DCE t-1,2-DCE VC Total Mar-06 687 47.1 0.477 0.000 5.229 0.486 0.005 0.016 5.736 Jun-06 275 20.9 1 0.000 2.093 0.216 0.010 0.016 2.335 Aug-06 560 45.7 0.461 0.000 4.262 0.471 0.005 0.016 4.754 Oct-06 232 227 2 2 0.000 1.766 2.342 0.021 0.032 4.160 Nov-07 1.15 197 2 6.79 0.000 0.009 2.032 0.021 0.109 2.170 Jan-08 0.411 162 1 3.15 0.000 0.003 1.671 0.010 0.050 1.735 Apr-08 0.512 153 1 2.23 0.000 0.004 1.578 0.010 0.036 1.628 Jul-08 1.06 155 1 1.73 0.000 0.008 1.599 0.010 0.028 1.645 Oct-08 0.382 162 1 1.9 0.000 0.003 1.671 0.010 0.030 1.715 Jan-09 0.304 137 1 0.964 0.000 0.002 1.413 0.010 0.015 1.441 Apr-09 0.277 121 1 0.679 0.000 0.002 1.248 0.010 0.011 1.271 Jul-09 0.333 126 1 0.984 0.000 0.003 1.300 0.010 0.016 1.328 Oct-09 0.447 100 1 0.922 0.000 0.003 1.032 0.010 0.015 1.060 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 * Values less than reporting limit =reporting limit Plot of Chlorinated Ethene Molar Concentrations vs. Time 7.000

6.000

5.000 .....PCE 4.000 _ TCE 3.000 ...... c-1 ,2-DCE rn 2.000 ""'*-t-1 ,2-DCE 1.000 -..VC - Total 0.000

p:\prOjectiAndrews AFB Environmental\Five-year reviews\4 . 0_Deliverables\4 . 1 _Reports\Dra~pendix 0 ST-14 ARARs, MK Test Results, Regression Plots\files\Ceth vs time MW13 • ./2010 Plot of Chlorinated Ethene Molar Concentrations vs. Time • MW15-ST14 Andrews Air Force Base, Maryland

Mass Concentration, ug/L Calculated Molar Concentration, mmollL Date PCE TCE c-1,2-DCE t-1,2-DCE VC PCE TCE c-1,2-DCE t-1,2-DCE VC Total Mar-06 241 14.2 1 1 0.000 1.834 0.146 0.010 0.016 2.007 Jun-06 233 12.7 1 1 0.000 1.773 0.131 0.010 0.016 1.931 Aug-06 243 12.8 1 1 0.000 1.849 0.132 0.010 0.016 2.008 Oct-06 265 14.9 1 1 0.000 2.017 0.154 0.010 0.016 2.197 Nov-07 3 190 2 2 0.000 0.023 1.960 0.021 0.032 2.035 Jan-08 0.814 156 1 0.416 0.000 0.006 1.609 0.010 0.007 1.632 Apr-08 0.52 162 1 0.513 0.000 0.004 1.671 0.010 0.008 1.694 Jul-08 0.411 137 1 0.587 0.000 0.003 1.413 0.010 0.009 1.436 Oct-08 0.422 126 1 1 0.000 0.003 1.300 0.010 0.016 1.329 Jan-09 0.421 96.9 1 1 0.000 0.003 1.000 0.010 0.016 1.029 Apr-09 0.351 63.6 1 1 0.000 0.003 0.656 0.010 0.016 0.685 Jul-09 0.329 79.5 1 0.359 0.000 0.003 0.820 0.010 0.006 0.839 Oct-09 0.462 83.8 1 0.463 0.000 0.004 0.864 0.010 0.007 0.886 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 * Values less than reporting limit =reporting limit Plot of Chlorinated Ethene Molar Concentrations vs. Time 2.500

2.000 .....PCE 1.500 ~ TCE

1.000 ...... c-1,2-DCE

~ t-1 ,2-D CE rn 0.500 -+-VC

P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0_Deliverables\4.1_Reports\Draft\Appendix 0 ST-14 ARARs, MK Test Resu lts, Regression Plots\files\Ceth vs time MW15 4/26/2010 Plot of Chlorinated Ethene Molar Concentrations vs. Time MW17-ST14 Andrews Air Force Base, Maryland

Mass Concentration, ug/L Calculated Molar Concentration, mmol/L Date PCE TCE c-1,2-DCE t-1,2-DCE VC PCE TCE c-1,2-DCE t-1,2-DCE VC Total Mar-06 1240 236 1.48 2.25 0.000 9.438 2.434 0.015 0.036 11.923 Jan-08 1380 215 1.54 2.8 0.000 10.503 2.218 0.016 0.045 12.782 Apr-08 1150 229 10 10 0.000 8.753 2.362 0.103 0.160 11 .378 Jul-08 402 1230 10 10 0.000 3.060 12.688 0.103 0.160 16.011 Oct-08 10 18.7 10 10 0.000 0.076 0.193 0.103 0.160 0.532 Jan-09 5 2260 4.04 1.66 0.000 0.038 23.313 0.042 0.027 23.419 Apr-09 2.68 1580 5.43 3.26 0.000 0.020 16.298 0.056 0.052 16.427 Jul-09 10 1540 3.49 2.7 0.000 0.076 15.886 0.036 0.043 16.041 Oct-09 20 1380 20 20 0.000 0.152 14.235 0.206 0.320 14.914 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 * Values less than reporting limit = reporting limit Plot of Chlorinated Ethene Molar Concentrations vs. Time 25.000

20.000 -.-PCE 15.000 _ TCE

10.000 ...... c-l ,2-DCE -*-t-l,2-DCE rn 5.000 ~ VC

0.000 _ Total

P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0_Delive rables\4.1_Reports\Draft\Append ix D ST-14 ARARs, MK Test Results, Reg ression Plots\files\Ceth vs t ime MW17 • • ./2010 Plot of• Chlorinated Ethene Molar Concentrations vs. Time • • MW19-ST14 Andrews Air Force Base, Maryland

Mass Concentration, ug/L Calculated Molar Concentration, mmol/L Date PCE TCE c-1,2-DCE t-1,2-DCE VC PCE TCE c-1,2-DCE t-1,2-DCE VC Total Mar-06 2610 15.4 0.354 1 0.000 19.865 0.159 0.004 0.016 20.043 Jan-08 2580 11.4 0.294 1 0.000 19.636 0.118 0.003 0.016 19.773 Apr-08 1880 15 10 10 0.000 14.309 0.155 0.103 0.160 14.727 Jul-08 1960 21.4 10 10 0.000 14.918 0.221 0.103 0.160 15.402 Oct-08 1170 9.43 20 20 0.000 8.905 0.097 0.206 0.320 9.528 Jan-09 412 1420 10 10 0.000 3.136 14.648 0.103 0.160 18.047 Apr-09 8.25 987 10 10 0.000 0.063 10.181 0.103 0.160 10.507 Jul-09 2.93 1230 5 5 0.000 0.022 12.688 0.052 0.080 12.842 Oct-09 3.38 1260 10 10 0.000 0.026 12.997 0.103 0.160 13.286 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 * Values less than reporting limit =reporting limit Plot of Chlorinated Ethene Molar Concentrations vs. Time 25.000

20.000 -+-PCE 15.000 ___TCE "' I P 10.000 .....c-1,2-DCE

~ t-1,2 - DCE W5. 000 ....-VC

0.000

P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0_Deliverables\4.1_Reports\Draft\Appendix 0 ST-14 ARARs, MK Test Results, Regression Plot s\files\Ceth vs time MW19 4/26/2010 Plot of Chlorinated Ethene Molar Concentrations vs. Time MW34-ST14 Andrews Air Force Base, Maryland

Mass Concentration, ug/L Calculated Molar Concentration, mmollL Date PCE TCE c-1,2-DCE t-1,2-DCE VC PCE TCE c-1,2-DCE t-1,2-DCE VC Total Mar-06 137 1B.1 1 1 0.000 1.043 0.1B7 0.010 0.016 1.256 Jan-DB 105 11.5 1 1 0.000 0.799 0.119 0.010 0.016 0.944 Apr-DB 100 11.5 1 1 0.000 0.761 0.119 0.010 0.016 0.906 Jul-OB 96.1 11.2 1 1 0.000 0.731 0.116 0.010 0.016 0.B73 Oct-DB 96.1 10.6 1 1 0.000 0.731 0.109 0.010 0.016 0.B67 Jan-09 26.B 56.6 1 1 0.000 0.204 0.5B4 0.010 0.016 0.B14 Apr-09 29.9 67.B 1 1 0.000 0.22B 0.699 0.010 0.016 0.953 Jul-09 49.2 73.4 1 1.0B 0.000 0.374 0.757 0.010 0.017 1.159 Oct-09 1 102 1 0.B7 0.000 O.OOB 1.052 0.010 0.014 1.0B4 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 * Values less than reporting limit =reporting limit Plot of Chlorinated Ethene Molar Concentrations vs. Time 1.400

1.200 ..

1.000 .. ~. ~ -+-PCE 0.800 - /' _ TCE -"'\. ~.-6 0.600 ""-c-l,2-DCE

0.400 V ~ t-l , 2-DCE

rn 0.200 / \. ~ .....VC 1- J - - ~ 0.000 - - ."'-. _ Total

P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0_Deliverables\4.1_Reports\Draft\Appendix D 5T-14 ARARs, MK Test Results, Regress ion Plots\files\Ceth vs time MW34 • • .2010 •

l> ""CI ""CI m :2 C >< • m

• Joint Base Andrews - First Five-Year Review November 2010 •• MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011)

APPENDIXE FT-02 ARARS

•

• P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0 Deliverables\4.1 Reports\Final\AndrewsAFB 5-Yr Review Revised March 201l.doc ,- - -­ • • • Table B-1 Summary of Potential Federal and State ARARs FT-02 Record of Decision, Andrews AFB, Maryland

Federal or State Statute, Type of ARAR Regulation or Guidance Summary of Requirement ARAR Category Comments 0; . :'> .' , ' ~, ~~'r ...·,)S~r ~ , .,;.,', , .::\~:~~ -,' " ". .• '::':.. . Site Cleanup .. '.', ',', ' . USEPA Guidance: Selecting Provides for the use of RBCs in TBC Chemical Applies to risk assessment. Exposure Routes and COCs by coinparison to existing concentrations at Risk-Based Screening (use current a site to screen out contaminants of RBC tables) concern. RCRA Subtitle C, 40 CFR Part 264 General Facility Standards provide for RA Action Applies to investigation-derived waste. Subparts B, C, D, and F security at the'site, periodic inspections, management of inc~mpatible wastes, contingency planning, monitoring and corrective action for releases, etc.

o • -.;,.:v=: ~ '. .. " "-;~"\~; .-:>t:"-·s··:' ..... ; ~; ;', " ,.,,', . ,}' ~ ' .. ";,:,'..'~:<.,tt " <,;,t.,:::;" .. 'V'.";"''/Y!1. '...... :.,.., d',' '..: .... "/",,':..,, Water'ry·" ;;;,.:: .'.>,', '.;:,.... , ...... Safe Drinking Water Act, Public Provides MCLs for the concentration of A Chemical Potential cleanup standards for groundwater at the Law 93 -523,40 CFR Part 141 common contaminants in public site. driilking water supplies. Maryland Drinking Water Quality These rules parallel the Federal drinking RA Chemical Potential cleanup standards for groundwater at the Standards, COMAR 26.04.01.06, water rules. " site; apply to the extent that they are more CO MAR 26.04.01.07 stringerit than the federal standard. Maryland Water Supply and Prohibits the installation of individual TBC Action, Drinking water supplied to Andrews AFB through Sewerage Planning, COMAR wells for drinking water supply in areas Location public utility (WSSC). Installation of new wells 26.03.01.05 already served by adequate community lfor drinking water supply is therefore prohibited at drinkiilg water supplies. any site at Andrews AFB,including FT-02. Maryland Water Pollution Establishes criteria and standards for A Chemical May apply to injection material. Regulations, CO MAR 26.08 surface and groundwater discharge limitations and policy for anti­ degradation of waters of the state. Maryland issues a water quality certification for proposed discharges into waters ofthe state; certification ensures that water quality standards are ilOt violated.

Pagelof2 Table B-1 SuimiIary of Potential Federal and State ARARs (Continued)

Federal or State Statute, Type of ARAR Regulation or Guidance Summary of Requireinent ARAR Category Comments ',:·"Y. ,", , .•.. < " '. , •. )!~'!il . .:~(: ~ , .... ,,< .~ . ",~. ".,<,'." '. f:: . .'~ >.. " ,""., .Misceilaneous ..:' .:. Maryland Occupational, Industrial, Provides limits on the maximum A Action Applies to site investigation and remedial and Residential Hazards allowable levels of noise anhe site activities. Regulations, COMAR 26.02 boundaries during site remediation work to protect the health, general welfare, and property of the people ofthe state. Maryland Water Supply, Sewage, Provides specifications for well RA Action Restoration of groundwater quality may be Disposal, and Solid Waste construction and abandonment. required. Also applies to well construction and Regulations, COMAR 26.04 abandonment. Maryland Board of Well Drillers Provides licensing requirements for A Action Applies to installation of new monitoring wells. Regulations, CO MAR 26.05 persons drilling and installing wells in the state. Assures that monitoring wells are Installed by qualified weli drillers. Applicable FAA regulations FAA waivers and Airfield Construction RA Location Applies to site investigation and remedial waivers required for site investigation activities. and construction activities. A - Applicable RequIrement RA = Relevant and Appropriate Requirement TBC = To Be Considered COC = chemical of concern COMAR 26 = Code of Maryland Regulations Title 26, Department-of the Environment (January 7, 2005). CFR = Code of Federal Regulations FAA = Federal Aviation Administration MCL = Maximum Contaminant Level RBC = risk-based concentration RCRA= Resource Conservation and Recovery Act USEPA = United States Environmental Protection Agency Action = Action-specific ARAR; detennined according to the specific technologies or activities taking place under an alternative. Chemical = Chemical-specific ARAR; regulatory health- or risk-associated numerical value that governs acceptable concentrations of a chemical in environmental media such as soil, water, or air. Location = Location-specific ARAR; determined according to site~related characteristics such as geology, floodplains, wetlands, historic places, and federal regulation of air facilities. • • •

l> ""C ""C • ITI Z C >< ."

• Joint Base Andrews - First Five-Year Review November 2010 MACTEC Engineering and Consulting, Inc. Project Number 3350092494 (Revised March 2011) •

APPENDIXF FT-03 MANN-KENDALL TEST RESULTS

•

• P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0 _ Deliverables\4.1_ Reports\Final\AndrewsAFB _ 5-Yr Review_Revised March 201l.doc '" . -..'" . )MAROS MaIln-Kendall StatIstICS. Summary ." .

Project: Andrews Air Force Base User Name: Washburn Location: Camp Springs State: Maryland

Time Period: 3/29/20021 to 3/12/20091 Consolidation Period: No Time Consolidation Consolidation Type: Median Duplicate Consolidation: Average NDValues: 1/2 Detection Limit J Flag Values: Actual Value

All Sourcel Number of Number of Coefficient Mann·Kendall Confidence Samples Concentration Well Tail Samples 'Detects of Variation Statistic in Trend "ND" ? Trend,

Arsenic

MW01-FT03 S 6 1 0,34 -1 50.0% No S MW02-FT03 T 5 2 0,56 -1 '50.0% ' No S MW03-FT03 T 7 0 0.40 -1 50.0% Yes ND MW04-FT03 T 6 6 0.35 -8 89.8% No S MWO&:FT03 T 5 0.37 -1 50.0% No S MW07-FT03 T 7 0.48 4 66.7% No NT MWOB-FT03 T 5 0 0.00 0 40.8% Yes ND MW09-FT03 T 5 0 0.34 0 40.8% Yes ND • MW10-FT03 T 6 2 0.46 -6 81.5% No S 8enzo(a)pyrene

MW01-Ff03 S 6 0 0.49 . 4 70.3% Yes ND MW02-Ff03 T' 5 0 0.09 3 67.5% Yes ND MW03-Ff03 T 7 0 0.67 4 66.7% Yes ND MW04-FT03 T 6 1 0.49 4 70.3% No NT MW06-FT03 T 5 0 0.56 3 67.5% Yes ND MW07-Ff03 T 7 0 0.03 2 55.7% Yes ND MWOB-Ff03 T 5 0 0.56 3 67.5% Yes ND MW09-FT03 T 5 0 0.03 3 .67.5% Yes ND MW10-FT03 T 6 0 0.49 4 70.3% Yes ND Naphthalene

MW01-FT03 S 6 0 0.18 4 70.3% Yes ND MW02-FT03 T 5 0.16 3 67.5% No NT MW03-Ff03 T 7 0.40 6 76.4% No NT MW04-FT03 T 6 2 0.48 -8 81.5% No S MW06-FT03 T 5 0 0.20 3 67.5% Yes ND MW07-FT03 T 7 0.03· 5 71.9% No NT MWOB-FT03 T 5 1 0.19 5 82.1% No NT MW09-FT03 T 5 0 0.03 3 67.5% Yes ND MW10-FT03 T 6 0.17 4 70.3% No NT Note: Increasing (I); Probably Increasing (PI); Stable (S); Probably Decreasing (PO); Decreasing (D); No Trend (NT); Not Applicable (N/A)­ Due to insufficient Data « 4 sampling events); SourcelTaii (SIT)

• The Number of Samples and Number of Detects shown above are post-consolidation values.

MAROS Version 2,.2 2006, AFCEE Friday, January 29,2010 Page 1 of 1 •

•

:t:o "'tI "'tI m Z C >< C') Joint Base Andrews - First Five-Year Review November 2010 • MACTEC Engineering and Consulting. Inc. Project Number 3350092494 (Revised March 2011)

APPENDIXG RESPONSES TO REGULATORY COMMENTS

• P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0_Deliverables\4.I_Repolts\Final\AndrewsAFB _5-Yr Review_Revised March 201l.doc • RESPONSE TO COMMENTS FIRST FIVE-YEAR REVIEW

(' JOINT BASE ANDREWS MARYLAND

United States Air Force

Prepared for: The Air Force Center for Engineering and the Environment

Contract No. F AS903-0S-D-S775 Delivery Order 52

Prepared by: 'MACTEC MACTEC Engineering and Consulting, Inc. . Portland, Maine

October 2010 (Updated March 2011) • ) USEPA Comments dated September 17,2010

• Overall Comments 1. As far as submitting an administratively complete five-year review draft document, USAF's environmental consultant has done an excellent job, tracking the structure and requirements of the EPA guidance on five-year reviews very closely. In a few places, the order in which certain subsections appears deviates from how the guidance laid out, but all the necessary components appear to be included. However, I thought it important to flag a few substantive issues of concern regarding the following four sites on Andrews AFB: FT-04, ST-10, ST-14, and FT-03.

Response: Comment noted. No response required.

2. The title is conjilsing because many of the sites listed do not have the remedial action completed and therefore, no remedy is in place. The title could be simplified to state that the review is for Andrews AFB.

Response: Agreed. Also, to reflect the 2009 name change at the Base, the title will be changed to First Five-Year Review, Joint Base Andrews, Maryland.

Specific Comments

3. Site FT-04 (Fire Training Area): Manganese concentrations in groundwater remain a problem. It remains unclear whether USAF will meet the goal of reducing manganese concentrations at this site before 2015. Pilots on standby sleep at the Air Sovereignty Alert • (ASA) facility on the site, and there may be a risk of VOC vapor intrusion. The document suggests that VOCs in groundwater, which could vaporize and pose a risk to personnel at the site, is migrating away from the occupied building, so the concern is minimal at present. The USAF plans to continue to monitor wells on the site for benzene. The document asserts that ifa decreasing trend in VOC concentrations immediately surrounding the building are not observed in ji/ture tests of groundwater samples, then additional evaluation of this vapor intrusion pathway will be considered.

Response: The USAF will continue to monitor vot and manganese concentrations in groundwater at FT-04 and may perform additional risk assessment and remedial actions based on data evaluation.

4. Site ST-JO (PD-60 Spill Site): Apparently, USAF is considering constructing a new cargo­ handling building at this location, which could create a new exposure pathway for VOCs in the groundwater (i.e., vaporization). This construction is still at the planning stage, however, and otherwise, progress at this site is moving along in accordance with the ROD.

Response: Comment noted. No response required.

1 of9 • P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0_Deliverables\4.I_Reports\FinaI\Appendix G Resp to Regulatory Comments\Response to regulatory comments_JBA_5-yrReview.doc 5. Site ST-14 (East Side Gas Station Site): First, there is a monitoring issue for this site. The ROD for Site ST-14 requires extensive groundwater monitoring; § 2.12.2.2 ofthe ROD "anticipated to include quarterly groundwater monitoring for the first 18 months of the remedy • implementation, semi-annual monitoring for the second 18 months, and annual monitoring for years 4 through 30 or until the cleanup criteria are achieved." Remedial actions at this site were initiated in October 2007, soon after the ROD was signed. Section 4.3.3 of the draft review (P82) indicates that "[f}ive quarterly groundwater sampling events were completed through April 2009 as part ofthe performance monitoring program. " Section 4.6.1 ofthe draft review states that "[gJroundwater monitoring is presently being performed quarterly." However, monitoring well samples from late 2009 are the most recent groundwater data included in this draft review. It seems that more recent monitoring data should be included.

Response: The data evaluated in the Five-Year Review were the most recent available to the authors at the time the report was drafted.

6. Second, there is an issue relating to vinyl chloride. The ROD listed vinyl chloride as a COC, setting a cleanup criterion of 2 ppb. According to § 4.5.4.6 of the draft review (P91), a "detailed Mann-Kendall test was not performed on the vinyl chloride data" to evaluate the trend ofconcentrations ofthis COC and whether the cleanup criteria will be achieved in the estimated 20-to 30-year timeframe contemplated by the ROD. Although the review asserts that, in the most recent sample, vinyl chloride concentrations are under "either the reporting limit or the SRG," samples from at least one well had vinyl chloride concentrations greatly exceeding the MCL (MW37-STI4 has concentrations between 2.8 and 8.5 ppb). A more detailed analysis needs to be performed regarding vinyl chloride.

Response: Vinyl chloride is a reductive dechlorination degradation byproduct of TeE and DeE. The degradation rates are different, however, and as TeE concentrations decrease, DeE and vinyl chloride concentrations can, and often do, increase temporarily before ultimately decreasing. Based on review of available monitoring data, the conditions monitored at MWll and MW37 are in the increasing vinyl chloride concentration stage. Although the long-term persistence of vinyl chloride would be a concern, in the short term the presence of vinyl chloride is an indicator that TeE and DeE are being degraded. DeE remains to be degraded at MWll, and TeE and DeE remain to be degraded at MW37. Slight increasing trends in vinyl chloride concentrations at MWll and MW37 do not allow estimation of cleanup times.

The text of Subsection 4.5.4.6 will be revised as follows to indicate data trends and provide greater detail:

"Of the 36 monitoring wells evaluated for vinyl chloride, 34 had concentrations less than either the reporting limit or the cleanup criterion in their most recent (October 2009) sample, and 33 had concentrations less than either the reporting limit or the cleanup criterion in all four of the 2009 quarterly samples. Samples from three monitoring wells had vinyl chloride concentrations greater than the cleanup criterion at least twice in 2009. At MW11-ST14, vinyl chloride concentrations showed an increasing trend from 1.1 to 16.9 f!g/L between January 2008 and October 2009, coincident with a TeE decrease from 145

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P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0_Deliverables\4.I_Reports\Final\Appendix G Resp to Regulatory Comments\Response to regulatory comments_JBA_5-yrReview.doc to less than I IlglL. At MWI7-STl4, vinyl chloride concentrations increased from 2.2 to 3.6 IlglL between March 2006 and April 2009, and decreased to less than reporting limits in October 2009, coincident with a decrease in TeE from 1,240 Ilg/L to less than reporting • limits. There was no clear overall trend. At MW37-STI4, vinyl chloride concentrations varied between 2.0 and 8.5 Ilg/L between March 2006 and October 2009, and decreased slightly after that without a clear trend.

Under conditions of reductive dechlorination such as those at ST-14, TeE breaks down into DeE, vinyl chloride, and ultimately non-chlorinated end products. During this process, vinyl chloride concentrations can, and often do, increase temporarily as reductive dechlorination of TeE and DeE occurs. The elevated vinyl chloride concentrations at MWII-STI4, MWI7-STl4, and MW37-ST14 are indicative of the reductive dechlorination of TeE and DeE and may remain elevated until degradation of TeE and DeE is complete. They are expected to return to levels less than the cleanup criterion after degradation of TeE and DeE is complete. The increasing or unclear concentration trends for these three wells cannot be used to estimate a cleanup time. As noted above, however, the concentration of vinyl chloride in 34 of 36 monitoring wells was less than the cleanup criterion. Vinyl chloride concentrations will continue to be monitored for attenuation as part of the ongoing long term monitoring program at ST-14 during the timeframe required to attain site cleanup levels."

7. Site FT-03 (Old Fire Training Area/Golf Course): The ROD for Site FT-03 required installation of groundwater monitoring wells. A network of wells has yet to be installed, although a team "is currently discussing the appropriate location for possible additional monitoring wells." According to USAF's draft, it is unclear whether progress is on track to satisfy the ROD for FT-03 in a timely manner.

Response: Subsection 7.3.3 will be edited to state that the Tier I team agreed on the location of additional monitoring wells in May 20 I 0 and that sampling will resume as soon as the wells are installed.

USEPA Comments dated September 23, 2010 (Federal Facilities Restoration and Reuse Office)

1. Pg 2, paragraph that begins as "five year review reports identify deficiencies .... "thai statement is not really true. The purpose of the review is to determine whether the remedy remains protective and to evaluate the performance ofthe remedy.

Response: The sentence will be edited to read " ... identify issues that affect protectiveness ... "

2. Pg 10 states that the ROD for FT-04 was signed in November 2005. Is this the ROD that triggered thereview or is it ST-10 ROD? As it read the report, the ST-JO ROD deals with petroleum waste and would not trigger a CERCLA action? From the report, 1 am confused about what action has triggered the five-year review.

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• P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0 _ Deliverables\4.1_ Reports\Final\Appendix G Resp to Regulatory Comments\Response to regulatory comments_JBA_5-yrReview.doc Response: As stated on page 1, the signature date of the ST-lO ROD, September 28,2005 has been used as the trigger date for the Five-Year Review. The rationale is discussed in Subsection 3.1. •

3. As a reminder that if the remedial action has not been determined, you can not make a protectiveness determination. Therefore, for site FT-02, a protectiveness statement should not be made.

Response: The remedial action for FT-02 was selected in the October 2009 ROD, but had not been implemented when the Five-Year Review was drafted. Based on review of site information, Subsection 6.9 will be edited to read as follows:

"There has been insufficient time since ROD signature to implement the selected remedy at FT-02; therefore, a protectiveness statement cannot be made."

4. For those area where there is no further action and there was no remedial action selected, a protectiveness statement should not be made.

Response: For sites LF-06, LF-07, SS-26"SS-27, and SS-28, the protectiveness statement subsections will be edited to read as follows:

"A remedial action has not been selected for (site name); therefore, a protectiveness statement cannot be made."

5. Need a table that lists the issues, recommendations and milestones. Refer to page 4-13 in the 2001 Comprehensive Guidance.

Response: A table summarizing issues, recommendations and milestones will be prepared for each site with recommendations (FT-04, ST-IO, ST-14, and FT-03).

Comments contained in USEPA markup of Five-year Review text, September 17, 2010 The following comments are excerpted from USEP A's markup of the report text. Most of EPA's markup comments were editorial in nature and have been addressed/incorporated directly in the revised text and are not enumerated here.

1. Subsection 2.2.4.2. The reviewer noted that the vacuum enhanced recovery system operated at FT-04 from 1999 to 2000 was ineffective.

Response: Subsection 2.2.4.2 will be edited to include the following statement:

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P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0_Deliverables\4.I_Reports\Final\Appendix G Resp to Regulatory Comments\Response to regulatory comments_1BA_5-yrReview.doc "A comparison of the results of post-pilot test soil sampling with the soil sampling results from 1993 did not conclusively show a reduction in VOC concentrations in source area • soils, and the system was determined to be ineffective."

2. Subsection 2.3.2.2. The reviewer noted that USAF construction at FT-04 destroyed many ofthe monitoring wells that are needed to effectively monitor the performance and effectiveness of the remedy.

Response: The following text will be added to Subsection 2.6.1:

"During construction of the ASA facility, several monitoring wells were abandoned/destroyed. This was anticipated in the ROD which described the post-ROD monitoring well network as 3 existing wells (MW0401-FT04, MW9302-FT04, MW8801- FT04) and 6 replacement monitoring wells whose tentative location, based on the anticipated ASA facility footprint, was shown on ROD Figure 2-7. The USAF installed six replacement monitoring wells (MW0701-FT04 through MW0706-FT04) in 2007 and one (MW0901-FT04) in 2009. The result was a monitoring well layout consistent with the tentative layout in the ROD figure. Because fewer wells were destroyed than anticipated in the construction of the ASA facility, an extensive array of monitoring wells is available for sampling." ,

The Air Force believes this is consistent with the ROD and does not constitute failure of the institutional controls.

3. Subsection 2.3.2.2. The reviewer asked whether Institutional Control Monitoring Reports for • FT-04 have been submitted annually as required by the ROD. Response: The status of LUC monitoring is discussed in Subsection 2.6.1 which will be edited to indicate that the 2009 report was in preparation during the drafting of the Five-Year Review.

4. 'Subsection 2.5.6. The reviewer commented that the Five-Year Review should include interviews with community members.

Response: The 2001 Comprehensive Guidance does not mandate interviews with community members and they were not perfom1ed during the Five-Year Review. Public notice of the Five-Year Review was, however, published in the Capital Flyer and the ClintonlFt Washington Gazette newspapers. Interviews will be considered in future five-year reviews.

No change to the text is planned.

5. Subsection 2.6.2. The revie'vver commented that the vapor intnlsion exposure pathway should be evaluated at FT-04.

50f9 • P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0_Deliverables\4, I_Reports\Final\Appendix G Resp to Regulatory Comments\Response to regulatory comments_1BA_5-yrReview.doc Response: The USAF is in the process of evaluating the vapor intrusion exposure pathway and will provide a report when complete. • 6. Subsection 2.7. They reviewer noted that the cleanup level for manganese at FT-04 may not be met within the 1O-year goal.

Response: Please refer to the response to USEPA Specific-Comment 3 (September 17, 2010).

The Technical Assessment Summary in Subsection 2.6.4 will be revised tOJead as follows:

"It may take several years for anaerobic groundwater conditions resulting from injection of HRC® at Injection Area 3 to flush through the site, thereby allowing aerobic conditions conducive to precipitation of manganese to return. It is unclear whether aerobic conditions will return in time to meet the goal of attaining the manganese cleanup criterion by 2015; however, the HRC® injection at Injection Area 3 was not anticipated or considered in setting the 2015 cleanup goal. Although injection of ORC or similar product might accelerate the return of aerobic conditions and reduction of manganese concentrations, allowing anaerobic groundwater to flush naturally should be considered. This will allow full advantage to be taken of anaerobic conditions for degradation of carbon tetrachloride and for groundwater to return to aerobic conditions naturally."

7. Subsection 3.6.2. The reviewer commented that USEPA should be notified of any changes regarding the planned cargo-handlingfacility at ST-10. Response: USEPA will be kept apprised of plans for ST-10. • 8. Subsection 4.5.4.6. The reviewer asked why the Mann-Kendall test was not performed on the vinyl chloride data for ST-14.

Response: Please refer to the response to USEPA Specific-Comment 6 (September 17, 2010).

9. Subsection 4.6.1 (System Operations/Operation and Maintenance). The reviewer asked why more recent monitoring was not used in assessing remedy performance.

Response: Please refer to the response to USEPA Specific-Comment 5 (September 17,2010).

10. Subsection 7.3.3. The reviewer questioned the fact that discussions were ongoing pertaining to additional monitoring wells at FT-03.

Response: Please refer to the response to USEPA Specific-Comment 7 (September 17, 2010).

60f9 P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0_Deliverables\4.I_Reports\Fin'al\Appendix G Resp to • Regulatory Comments\Response to regulatory cOlilments_1BA_5-yrReview.doc USEPA Comments dated February 17, 2011 (from Division Director Ronald J. Borsellino)

1. Table of Contents, List of Appendices, Appendix G: Please delete all references to the FFA • Lists ofSites.

Response: The requested changes will be made.

2. Page 2, 1.1 Purpose and Scope, paragraph 6: Delete the reference to the FFA Appendix G.

Response: The requested change will be made.

3. Page 27, 2.5.6 Interviews. The purpose of interviews is to document community outreach to the public about the Five Year Review between the Air Force (AF), EPA, MDE, and Prince Georges County Health Department and the affected community members. It is not to document the contractors' discussions with the AF. Please reference and include outreach to the community such as, but not limited to, the vapor inhalation sampling, the contact between the AF and the Community with the installation of co detectors, as well as any community meetings attended where the cleanup progress has been discussed.

Response: The section on Interviews will be modified to indicate that no interviews were conducted, but that the public was notified through notices in the local papers and no comments or questions were received. The specific outreach activities mentioned in the Director's comment relate to the remedial program at Site SS-Ol, Brandywine DRMO, and will • be discussed in the Five-Year Review Report for that site. 4. (No comment was entered under Item 4 in the EPA Comment Letter. To avoid confusion, the numbering in the EPA letter will be retained in this Response to Comments.)

5. Page 28, 2.6.1 Question A: FT-04. Is the remedy functioning as intended by the decision documents? Please answer Yes or No. Then follow with the explanation. This occurs throughout the entire document. Please correct this for each ofthe sites included in the Five­ Year Review.

Response: The requested changes will be made for each site that received a full five-year review. The sites that received "Status Reviews" (i.e., sites at which a remedy had not been selected or not fully implemented at the time of the review, or sites with "No Further Action" remedies) will retain their current formatting.

6. Page 30, last paragraph: The report states that the ASA facility should be evaluated for the

"potential completeness of the vapor intntsion pathway n. On page 31, paragraph two, states "Collectively, the information suggests that VOCs in groundwater do not pose a vapor intrusion concern for the ASA building at FT-04." YOLI should also add that at this time the

70f9 • P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0_Deliverables\4.I_Reports\Final\Appendix G Resp to Regulatory Comments\Response to regulatory comments_JBA_5-yrReview.doc ASAfacility is unoccupied. Furthermore, you should note that the EPA and its toxicologist for the site has reviewed the current information and the potential for vapor intrusion into the ASA e facility and that EPA and its toxicologist agree with the conclusions that based upon the groundwaterflow direction as well as the concentration ofbenzene in MW0302-FT04 does not pose a vapor inhalation risk. .

Response: The suggested changes will be made to the text.

7. Page 33, Question C: Has any other information come to light that could call into question the protectiveness ofthe remedy? Previously, you mentioned the vapor inhalation potential at the ASA facility. However, review of the information suggests that there is no vapor inhalation risk at FT-04 due to the benzene contamination in the up gradient monitoring well. Moreover,

1 it is impossible to conduct a vapor inhalation risk assessment without having a building or structure present at the site. A vapor inhalation risk was considered but sampling to collect data to determine the risk could not be conducted because there was no building present during the remedial investigation, there is no direct correlation between groundwater ofsoil gas vapor concentrations and the potential for a vapor inhalation risk. .

Response: This section will be revised to indicate that the potential for a completed vapor intrusion pathway was considered and was determined to not pose an unacceptable risk. The text will also point out that no indoor air sampling was conducted during the RI, because no structures were present on site at that time.

8. Page 34, 2.7 Table. Yes, the protectiveness of the remedy as it relates to the ASA facility is warranted. Current and future protectiveness was determined to be protective because ofthe specific issues identified on page 33, 2.6.4 Technical Assessment Summary, paragraph two and e EPA's review of the iriformation. So, the Table should be Nand N for curre.nt and future protectiveness.

Response: The Table will be revised as suggested.

9. Page 34, 2.8 FT-04 Recommendations and follow-up actions. Based upon the iriformation presented and analytical data discussed on page 33, paragraph one: Vapor intntsion was evaluated and it was determined that there is no potential risk. So, the Table should be changed to "N" and "N" based upon 2.9 FT-04 Protectiveness Statement. Stating that the remedy is protective in 2.9 is contradicted by the two tables above on page 34 which states that the Current and Future Protectiveness is in question because ofthe vapor inhalation potential. Please correct this contradiction. .

Response: The apparent contradiction will be corrected.

10. Page 55,3.6.1 Question A: Is the remedy functioning as intended by the decision documents at ST-10? Please answer "yes" or "No".

Response: The response to Question A will be re-formatted to clearly answer "Yes".

80f9 e· P:\Projects\Andrews AFB Environmental\Five-year reviews\4.0_Deliverables\4.I_Reports\Final\Appendix G Resp to Regulatory Comments\Response to regulatory comments_1BA_5-yrReview.doc 11. Page 3.6.3 Question C: Haas any other information come to light that could call into question • the protectiveness of the remedy at ST-I0. Please correct to the following. "No. No other information has come to light that calls into question the protectiveness of the remedy other than the potential vapor inhalation risk if construction of the cargo handling building is constructed at the site. " .

Response: The suggested change will be made to the text.

12. Page 61, ST-10 Protectiveness Statement: ST-10 is protective currently. If and when the cargo building is planned to be constmcted, a vapor inhalation evaluation will need to be conducted to determine ifthere is the potential for a vapor inhalation risk so that engineering measures can be implemented in the design ofthe cargo building.

Response: The text will be revised as suggested in the comment.

I / 13. Page 73, 4.3.1, Remedial Action Objectives, bullet 4: "Prevent residential exposure to soil. " There is no cleanup criterion for soil yet the RAOs include "Prevent residential exposure to soil." Please clarify..

Response: This point will be clarified in Section 4.2.5, by indicating that the slight risk to a hypothetical future child resident from exposure to soil contaminants was assumed to be • addressed through institutional controls, and therefore no soil cleanup levels were established. 14. Page 91, 4.6.1 Question A: .Is the remedy fimctioning as intended by the decision documents at ST-14? Please answer "yes" or "No".

Response: The response to Question A will be re-formatted to clearly answer "Yes".

15. Page 98, 4.9 ST-14 Protectiveness Statement: Please add the following: The installation of additional monitoring wells and with sampling and analyses ·will be used to evaluate the performance of the remedy in the short and long-term. The installation of these monitoring wells will be used to determine ifadditional injections are necessary in accordance with the record ofdecision or ifadditional remedial measures are necessary.

Response: The requested change will be made to the text.

16. Appendix G Federal Facility Agreement List ofSites: Please delete.

Response: Appendix G will be removed from the document.

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