Draft Remedial Investigation Report for Pine Street Canal Site Burlington, Vermont

Site; Sfe£_i^^4^A/\j e Break: ^- ^ SDMS DocID 457822 Other; ^i52:M^

VOLUME IA DRAFT REMEDIAL INVESTIGA REPORT FOR PINE STREET C BURLINGTON, V

MAY 1990

ROL NUMBER 27

U.S. EPA CT NO. 68-01-7448 WORK AS NT NO. 10-1L19

PREPARED BY PEER CONSULTANTS, P.C.

**COMPANY CONFIDENTIAL** This document ^hafe been prepared for the U.S. Environmental Protection Agency under Contract No. 68-01-7448. The inaterial contained herein is not to" be disclosed to, or discussed with, or made available to any person or persons for any reason without prior approval of a responsible official of the U.S. Environmental Protection Agency. DISCLAIMER

THIS DOCUMENT IS A DRAFT WHICH HAS NOT RECEIVED FINAL ACCEPTANCE FROM THE U.S. ENVIRONMENTAL PROTECTION AGENCY OR THE VERMONT DEPARTMENT OF ENVIRONMENTAL CONSERVATION. THE OPINIONS, FINDINGS, AND CONCLUSIONS EXPRESSED ARE THOSE OF THE AUTHORS AND NOT THOSE OF THE U.S. ENVIRONMENTAL PROTECTION AGENCY OR THE VERMONT DEPARTMENT OF ENVIRONMENTAL CONSERVATION. PERFORMANCE OF REMEDIAL RESPONSE ACTIVITIES AT UNCONTROLLED HAZARDOUS WASTE SITES

REM VI U.S. EPA CONTRACT No. 68-01-7448

DRAFT REMEDIAL INVESTIGATION REPORT FOR PINE STREET CANAL SITE BURLINGTON, VERMONT

EPA WORK ASSIGNMEN' DOCUMENT CONTROL No.<

Prepared by Jeffr^yT^U^^Pa^cs ' ^ ^ Site Manage^-^'^^

Reviewed by: Date: SVL/_^

Reviewed by Date: 5 /G 190 Peter A. Crowley,^h.D( Quality Assurance/ Quality Control Manager

Approve Date: M. Rascher n 1, RPM VOLUME IA TABLE OF CONTENTS SECTION PAGE EXECUTIVE SUMMARY 1.0 INTRODUCTION /./..._. 1-1 1.1 Purpose of the Remedial Investigation. /., J.,/. l-l 1.2 Site Background .X?-^VC./. 1-2 1.2.1 Site Description ./>>../>K. 1-2 1.2.2 Site History •X; •/ 1-9 1.2.3 Coal Gasification at Manufactured Gas Plants 1-10 1.2.4 Previous Investigations 1-27 1.3 Remedial Investigation Suiiiifi!txy«.^. 1-40 2. 0 STUDY AREA INVESTIGATION .\. •^s^^s> 7? 2-1 2.1 Surface Features ^s....y^ 2-1 2.1.1 Objectives and Methoaoltegies 2-1 2.2 Geophysical Investigations 2-2 2.2.1 Objectives and Methodologies 2-2 2.2.2 Suwey^gyipment 2-3 2.3 Air Inves1îg^^tion< .-^.. >>7 2-4 2.3.1 0b3.ectiVes and Methodologies 2-4 2.4 Surface Water andySeîment Investigation 2-9 2.4.1 Objectives 2-9 2.4.2 Methodologies 2-9 2Â^,3L„^^^ Surface Water Sampling Locations 2-13 /l.A.A\^ Sediment Sampling Locations 2-15 2 .p êologâlv Investigation 2-18 X.^/&vl / y)bjectives 2-18 2s.5rVV /soil Gas Survey Methodologies 2-18 2rfev3 /Surface Soils Methodologies 2-23 2.5.4Ny Subsurface Soil Methodologies 2-28 VOLUME IA TABLE OF CONTENTS (Continued)

2.6 Groundwater Investigation 2-37 2.6.1 Objectives and MethodologiesyC./ 2-39 2.7 Ecological Investigations /.,/,./^ 2-43

2.7.1 Wetlands Delineation >K«./T.-/: 2-43 2.7.2 Ecological Populations ^V.. .fy. 2-44 2.7.3 Biota Sampling />>^.. >K; 2-44 3.0 PHYSICAL CHARACTERISTICS OF PINE STREET CANAL SITE'. 3-1 3.1 Surface Features 3-3 3.2 Climatology v<..,L* ^~^ 3.2.1 Temperature.. ,\., ~^,J^TT>>»„. 3-5 3.2.2 Precipitation. .\. .\T>?> ... .^. 3-13 3.2.3 Dry or Drought Perio^.yTTV. 3-15 3.2.4 Storms \.,,,/. 3-15 3.3 Surface Water Hydrology \ . \ 3-16 3.4 Geology .\/ 3-18 3.4.1 Soils 3-18 3.4.2 Regi^nals.Geology 3-20 3.4.3 Sii!e ..Gôlbgy 3-27 3.5 Hydrogeol9Â../. ..^..>;7. 3-37 3.5.1 R^g:ionai Hydrogeology 3-37 3.5.2 SiteNHyd^rqgeology 3-39 3.6 Demography and LarKKTJse 3-45 3.7 Ecology 3-46 Wetlands 3-46 ''3.7.2 \ Ecological Receptors 3-51 r773\ \ Sampling Activities 3-57 3V.8 êld QVQP Procedures 3-60 ^.l^y /Quality Control Samples 3-60 3.8vji / Sample Custody 3-62

« • 11 VOLUME IA TABLE OF CONTENTS (Continued)

3.8.3 Field Logboo k 3-62 3.8.4 Eguipment Decontaminatio n 3-62 3.8.5 Sample Collectio nand Identic 3.8.6 Sample Container Labelling.

3.8.7 Chain-of-Custody Records../Vs ^.../ 3-65 3.8.8 Sample Shipping .>s..^V> . 3-66 3.8.9 Analytical Data Validation ^V^./^ 3-67 4.0 NATURE AND EXTENT OF CONTAMINATION 4-1" 4.1 Blank Samples 4-2 4.2 Contaminant Source(s).... ycv^v^* 4-6 4.3 Air Monitoring y,,. /TrrvNi^ 4-7 4.3.1 Real Time PersonXelNMoi^itoj^j/A g 4-7 4.3.2 Ambien tAir Monitoring. X 4-10 4.3.3 Conclusions X^../ . 4-19 4.4 Surface Water and Sediments... \ ./..- 4-23 4.4.1 Surface Water Analytical Results 4-23 4.4.2 Sedi Analytical Results 4 36 4.5 Soils Investy suits 4 -54 4.5.1 Samples 4- •54 4.5.2 amples 4* 57 4.5.3 c Surface Soil Samples 4 57 4.5.4 oil 4 -68 4.6 Groundwater Investigation Results 4-103 4.6.1 Volatil eand Semivolatile Organic Analyses.. 4-106 Inorganic Analyses 4-124 4-133

iii VOLUME IB TABLE OF CONTENTS SECTION 5.0 CONTAMINANT FATE AND TRANSPORT. .5-1 5.1 Physical/Chemical Characteristics and Associated Transport Mechanisms 5-1 5.1.1 Polycyclic Aromatic HydrocajfbohsyfPAHs). .5-4 5.1.2 Other Semivolatile Organics. A ,yi./. 5-9 5.1.3 Volatile Organics Vs.. ^S/ ./. 5-9 5.1.4 Trace Elements '^X; * * ^ 5-11 5.1.5 Cyanides >v../Vv. 5-14 5.2 Potential Routes of Migration ^V/ 5-16 5.2.1 Surface Soil 5-16 5.2.2 Sediment 5-18 5.2.3 Subsurface Soi^....TTT^*-,^..^.^ 5-20 5.2.4 Groundwater... A,. .Vr>^ . .77^ 5-22 5.2.5 Surface Water.. .\. .\./. ./rw/ 5-24 5.2.6 Biota \. .Y. / 5-25 5.2.7 Air Pollution \...(.,. 5-26 6. 0 HUMAN HEALTH EVALUATION .\ / 6-1 6.1 Introduction 6-1 6.1.1 Oroanlzardon of the Risk Assessment...... 6-2 6.2 Identifica/i s of Potential Concem...6-3 6.2.1 d^k^ Evaluation 6-3 6.2.2 Soil^ . >K. .' 6-6 6.2.3 Surfcibe Wa^er 6-15 6.2.4 Sedimentvy. 6-19 6.2.5 Groundwater 6-22 6.2.6 Air 6-25 6.3 ure Assessment 6-26 Potentially Exposed Populations 6-33 Identification of Exposure Pathways 6-34 uantification of Exposure 6-42 dentification of Uncertainties 6-62 VOLUME IB TABLE OF CONTENTS (Continued)

6.4 Toxcity Assessment 6-63 6.4.1 Carcinogenic Chemicals of Potentl Concem •/' •/ 6-70 6.4.2 Noncarcinogenic Chemicals of Poce^ie Concern /• •/* •/* *^ 6-77 6.4.3 Applicable or Relevant and Apprdpriat Requirements (ARARs) • "Xr • • • •/ 6-85 6.4.4 Identification of Uncertainties>Vv...>r. 6-89 6.5 Risk Characterization ^>yyi... .6-90 6.5.1 Current Lan dUse... 6-92 6.5.2 Future Land Use 6-106 6.5.3 Identification of Uncertainties in the RiskCharacteri2ationrrT>».^. 6-129 6.6 Summary of the Human Health Evaljaation^ 6-134

7.0 SUMMARY AND CONCLUSIONS X-.V.. 7-1 7.1 Summary >i 7-1 7.1.1 Geology and Topography 7-1 7.1.2 Nature/andBxtent of Contamination 7-2 7.1.3 Fate zmd'âi^sport 7-7 7.1.4 Human Health ^vih^ûation 7-9 7.2 Recommendat>^ri^v. J... ?">*/. 7-11 7.2.1 RecommerMed Remedial Action O jb ectives 7-11 7.2.2 Data Limit^tîpns and Recommendations for Future Research 7-12 REFERENCES ATTACHMENTS

11 VOLUME III TABLE OF CONTENTS

APPENDIX

B Previous Investigation Data Bl: Spreadsheets Containing Previous Investigation Data B2: Previous Investigation Data: Definit^arjd Estimated Concentrations Geotechnical Data Cl: Laboratory Geotechnical Data C2: Graphs Used in Estimating Hydraulic CondudtiVity C3: Previously Existing Laboratory Permeability Data C4: Previously Existing Consolidation Test Data C5: Previously Existing Grain "l^iz^ Distribution Curves Analytical Data Dl: Complete Analytical Data Re£ D2: Analytical Results Showing Onl^ Detected Values

TOC-i VOLUME IV TABLE OF CONTENTS

APPENDIX

E Air Samples El: Work Sheets E2: Calibration Charts E3: Data Charts Geologic and Hydrogeologic Data Fl: Visual Comparison of Well Depths reened Intervals F2: Soil Boring Logs F3: Well Logs

G Exposure Calculations

H. Toxicology Profiles

TOC-i VOLUME IA LIST OF FIGURES

Ficmre Title Page 1-1 General Hap of New England Area 1-3 1-2 State Map of Vermont 1-4 1-3 City of Burlington, Vermont 1-4 1-4 Pine Street Canal Site 1-6 1-5 Topographic Map of the Pine Street C 1-8 1-6 Cycles of a Carburetted Water-Gas ( 1-17 1-7 Cycles of a Carburetted Water-Gas ( 1-18 1-8 Cycles of a Carburetted Water-Gas (CWG) 1-19 1-9 Flowchart for a Carbureted Water-Gas 1-20 1-10 Previous Investigations 1-29 1-11 Burlington Southern Connector Vermont AOT Boring A2-A9 Locations l-33r 1-12 Burlington Southern Connector Permit Application, Groundwater Sample Locati 1-32 1-13 RCRA Facility Assessment /6amplil cations 1-35 1-14 Summary of Environmental Varif e GE Company, Burlington Facility Samplli^g 1-36 1-15 Ultramar Petroleum, Incorpo ifnvironmental Site Assessment Sample Locatlpns 1-38 ll 1-16 Wiessner Property and St. Joh Trucking Sites Subsurface Investigation Sampl cation 1-39 1-17 Blodgett Oven Company, Inc. Su rface Investigation Sample Locations 1-41

2-1 Ambient Air Locations 2-8 2-2 Surface Wa .cations 2-14 2-3 Sediment s 2-17 2-4 Soil Gas catrtbns 2-20 2-5 Systematic Sii' Soil Sampling Locations 2-24 2-6 Background,Surf il Locations 2-26 2-7 Sampling Location r Dioxin Screening 2-27 2-8 Monitoring Well and Boring Locations (Installed by PEER) 2-29 2-9 Boring Locations (Installed by PEER) 2-32 2-10 ing Well Locations (Installed by PEER) 2-36 2-11 ' L^te Monitoring Well Locations and Vstalled by PEER 2-42 2-12 .ing Locations 2-45

IV VOLUME IA LIST OF FIGURES (Continued)

riqur? Title 3-1 Pine Street Canal Site 3-2 3-2 Drainage Patterns 3-17 3-3 Physiographic Provinces 3-21 3-4 Geologic Map of Vermont 3-22 3-5 Geological Map of Burlington 3-23 3-6 Maximum extent of Glacial and Post es 3-25 3-7 Till and Clay Deposits 3-26 3-8 East-West Cross Section Line 3-29 3-9 East-West Cross Section 3-30 3-10 North-South Cross Section Line 3-31 3-11 North-South Cross Section 3-32- 3-12 Isopach Thickness of Sand Unit 3-34 3-13 Isopach Thickness of Peat 3-36 3-14 Isopach Thickness of Fill 3-38 3-15 Potentiometric Surface andT Sttriicial Aquifer 3-40 3-16 Potentiometric Surface ir\ Lo^i^-Sltfe..^ay Aquifer 3-44 3-17 Current Property Divisions 3-47 3-18 Species Habitat 3-55

4-1 Real Time Air Monitoring at Selepxed Drilling Locations 4-9 4-2 Well Locations and Estimated Real Time Air Monitoring Val

VI VOLUME IB LIST OF FIGURES

Fj-qure xm£ Pag?

6-1 Soil Opereible Units 6-11 7-1 Total PAHs in Surface Soils/Sediment 7-6

iii VOLUME IA LIST OF TABLES

Table Title Page 1-1 Site Remedial Chronology for Pine Street^Canal Site 1-11 1-2 Coal-Tar Constituents 1-21 1-3 Process Residuals from Manufactured Ga^ Plants 1-22 1-4 Predominant Chemical Classes Present Xn/Vroj£k9s Residuals 1-23 1-5 Physical and Chemical Properties of 1-26

2-1 Surface Water and Sediment Sample Locatiom and Descriptions 2-16 2-2 Boring Information 2-33 2-3 Soil Boring Sampling Locations and Descriptions 2-34 2-4 Monitoring Well Sample Locations and Descriptions 2-38 2-5 Monitoring Well InformatJ( 2-40

3-1 Temperature and Precipitatic lington. Vermont 3-6 3-2 Precipitation - Huntington Cerit Vermont 3-7 Frequencies of Selected Tempera^ e, etc.. 3-3 Burlington, Vermont 3-8 Probabilities of Freezing, etc., Burlington, 3-4 Vermont 3-9 Average Freqi^n^ o^ Possible Drying, etc., 3-5 Burlington, 3-10 Average Fr g, etc., Burlington, 3-6 Vermont 3-11 3-7 Weather Rec , Vermont 3-12 3-8 Owners and La at Pine Street Canal Site 3-48 3-9 On Site Vegetatr Wetland Indicator Status 3-52 3-10 Avi Fauna 3-58 3-11 Fish Sampling Results 3-59

4-1 served Concentrations in Blank Samples 4-4 4-2 erved Concentrations in Blank Samples 4-5 4-3 r Volatile Analyses, Round One 4-13 4-4 ir Semivolatile Analyses (ug/m') Round One 4-15

Vll VOLUME IA LIST OF TABLES (Continued) Tabl^ Titlg Page 4-5 Ambient Air Semivolatile Analyses (ug/m; ound Two 4-18 4-6 Ambient Air Semivolatile Analyses (ug/ ound Three 4-20 4-7 Organic Compound Concentrations in 9 face Water (ug/1) 4-24 4-8 Organic Compound Concentrations in Of Surface Water (ug/1) 4-25 4-9 Organic Chemicals Detected in Surface Wat^ 4-28 4-10 Inorganic Chemicals Detected in Surface Wate 4-32 Chemicals Detected in Background Surface Water 4-11 Samples (ug/1) 4-34 4-12 Organic Chemicals Detected in Sediments 4-37 4-13 Total BTEX Concentrations/foiL Canal Sediments 4-41 4-14 Total PAH Concentrations ediment Samples 4-44 4-15 Inorganic Chemicals Deted ts 4-51 4-16 Organic Chemicals Detected\in 'nd Soil 4-55 4-17 Inorganic Chemicals Detecte ckground Soil 4-56 4-18 Chemical Detected in Surface 4-58 4-19 Total BTEX for Each Subsurfac 1 Location 4-72 4-20 Summation Chart for Total PAH 6entrations for Subsurface Soils 4-82 4-21 Inorganic Chemicals Detected in the Subsurface 4-97 Soils ^ 4-22 y^ 4-104 4-23 Organic Chemicals Detected in Ground Water 4-126 4-24 Inorganic Chemicalsl©etected in Ground Water 4-134 4-25 Fish Tissusf Analysis Data^ (Golden Shiner) 4-136 4-26 Fish Tissu^ft\^lysi^~'tJ^t^ (Yellow Perch) 4-138 Fish TissueN^aly^s Da« (Northern Pike) 4-141 4-27 Summary of Fi ^ Trsisue Analyses

Vlll VOLUME IB LIST OF TABLES

TiU£ 5-1 Physical, Chemical and Fate Data for Site Specific Chemicals 5-1

6-1 Chemicals Detected in Surface Soil 6-8 6-1-1 Background Concentrations of Inorge Surface Soil •10 6-2 Chemicals Detected in Subsurface Soili •12 6-3 Chemicals Detected in Surface Water •17 6-4 Chemicals Detected in Surface (0-6") •20 6-5 Chemicals Detected in Ground Water 23 6-6 Chemicals Detected in Air •27 6-7 Summary of Chemicals of Potential Concem •28 6-8 Surface Soil Chemicals of,^^ncern by Operable Unit 30 6-8-1 Surface Water Cheicals o. n Operable Units One and Two 32 6-9 Summary of Potential Expd 35 6-10 Summary of Exposure Assess Current Land Use 6-47 6-11 Summary of Exposure Assessme Future Land Use •54 6-12 Toxicity Values: Potential Non^rcinogenic Effects •65 6-13 Toxicity Values: Potential Carcinogenic Effects 6 -68 6-14 Applicable or Relevant and Appropriate Requirements6 •86 6-15 Summary of Np^icarb^nogenic Risks Posed by the Ingestion in Surface Water by Swimmers Current La 6-94 6-16 Summary o c Risks Posed by the Dermal Ab micals in Surface Water While Swimm" rent Land Use 6-95 6-17 Summary of Ex ncer Risk Posed by the Ingestion and De ^ Absorption of Chemicals in Surface Water While Swimming Current Land Use 6-96 6-18 Summary of Noncarcinogenic Risks Posed by the Ingestion of Surface Soil" and Sediments by Child Tresp^sers Current Land Use 6-97 6-19 /e.„-«,,-^. Qf Noncarcinogenic Risks Posed by the of Surface Soil" and Sediment by Adult rs Current Land Use 6-98 6-20 Noncarcinogenic Risks Posed by the sorption of Chemicals in Surface Soil" lent by Trespassers Current Land Use 6-99

IV VOLUME IB LIST OF TABLES (Continued) Table 6-21 Summary of Excess Lifetime Cancer Risk Posed by the Ingestion of Chemicals in Surface Soil* ^U)d Sediments by Child Trespassers Current Land Use 6-100 6-22 Summary of Excess Lifetime Cancer Ri y the Ingestion Chemicals in Surface Soil' 'ments by Adult Trespassers Current Land Us 6-101 6-23 Summary of Excess Lifetime Cancer Risk^ the Dermal Absorption of Chemicals in Su Soil" and Sediment by Trespassers Current Use 6-102 6-24 Summary of Noncarcinogenic Risks Posed by the Consumption of Contaminated Fish by Local Residents Current Land Use 6-105 6-25 Summary of Noncarcinogeni isks Posed by the Ingestion of Groundwater as a Potable Water Supply Future Land Use 6-107 6-26 Summary of Excess Lifetim Posed by the Ingestion of Chemicals ter Used As a Potable Water Supply Fviture nd use 6-108 6-27 Summary of Noncarcinogenic Ri by the Ingestion of Surface Soil by c! ren Future Land Use 6-111 6-28 Summary of Noncarcinogenic Risk Posed by the Dermal Absorptipn of Chemicals in Surface Soil •-1 by Children F>l€ur^Land Use 6-112 6-29 Summary of ogenic Risks Posed by the Ingestion 1 by Adults Future Land Use 6-113 6-30 Summary o Risks Posed by the Dermal Ab^ icals in Surface Soil by Adults/G Future Land Use 6-114 6-31 Summary of etime Cancer Risk Posed by the Ingestion an al Absorption of Chemicals in Surface Soil by hildren Future Land Use 6-115 6-32 Summary of Excess Lifetime Cancer Risk Posed by the Ingestion and Dermal Absorption of Chemicals ace Soil by Adults/Gardeners nd Use 6-116 Noncarcinogenic Risks Posed by the f Soil by Children Following of Subsurface Soil Future Land Use 6-118 Noncarcinogenic Risks Posed by the rption of Chemicals in Soil by Chi^b4rej<' Following Disturbance of Subsurface Soil Future Land Use 6-120 VOLUME IB LIST OF TABLES (Continued) llils. 6-35 Summary of Noncarcinogenic Risks Posed by the Ingestion of Soil by Adults Following Disturbance of Subsurface Soil Future Land Use 6-121 6-36 Summary of Noncarcinogenic Risks Posec Dermal Absorption of Chemicals in Soi ts/ Gardeners Following Disturbance of Soil Future Land Use 6-123 6-37 Summary of Excess Lifetime Cancer Ri^ the Ingestion of Soil by Children Foll( Disturbance of Subsurface Soil Future 6-124 6-38 Summary of Excess Lifetime Cancer Risk PosedNCy the Dermal Absorption of Chemicals in Soil by Children Following Disturbance of Subsurface Soil Future Land Use 6-125 6-39 Summary of Excess Lifetinyf^-Gajicer Risk Posed by the Ingestion of Soil by/Adults"~Following Disturbance of Subsurface^ s5^1r--Iiitxirfe^~;Jiand Use 6-126 6-40 Summary of Excess Lifetimes Canc^ltisJc Posed by the Dermal Absorption of Cntemicals in Soil by Adults/Gardeners Following Disturbance of Subsurface Soil Future Land Future Land Use 6-127 6-41 Summary of Noncarcinogenic Risk^ Posed by the Inhalation of Chemicals in Ambient Air by On-site Resident9\Future Land Use 6-130 7-1 Summary of ilb-Qf Potential Concern at Pine Streei Site^\Burlington, Vermont 7-3 7-2 Summary of ^^Roteht^al Human Health Risks Estimated for the Pine street Canal Site 7-10

Vi LIST OF ACRONYMS

ACL Alternate Concentration Limits API American Petroleum Institute ARAR Applicable or Relevant and Appropriate Requirements ATSDR Agency for Toxic Substances and D^^ase^Registry AWQC Ambient Water Quality Criteria B/N Base/Neutral Extractables B/N/A Base/Neutral/Acid Extractables BTEX Benzene, Toluene, Ethylbenzene, Xylene BTU British Thermal Unit CAA Clean Air Act CAS Chemical Abstract Sei CC Coal Carbonization CERCLA Comprehensive EnvironmentalvJ^esponse, Compensation, and Liability Act of 1980, also known as Superfund: Amended in 1986 by the Superfund Amendments and Reauthoriztiti<^ Act (SARA). CLP Contra Program (EPA) CRL Cent oratory CRP Communit ions Plan CWA Clean Water CWG Carburetted Water Gas or Water Gas DMP H Management Plan DOT epartment of Transportation DQO ality objectives EPA . Environmental Protection Agency

IX LIST OF ACRONYMS (Continued)

FIT Field Investigation Team FOP Field Operations Plan GPR Ground Penetrating Radar GC/MS Gas Chromatography/Mass Spectres GWPS Ground Water Protection Strate HSP Health and Safety Plan ID Intemal diameter IRA Immediate Removal Action

IRIS Integrated Risk Info System Lead agency The agency, either eral agency, or appropriate State having primary responsibility and a for planning and i l executing the remediati a site. Maximum Contaminant Level Maximum Contaminant Level Goal Manufacttlred oas Plant Mean sea/lev^l^^\,_^ Natioh^ AiWDient Air Quality Standard Non-Ague OUS. Pheifie Liquids National Contingency Plan National Institute for Occupational Safety and 1th nal Pollution Discharge Elimination System al Priorities List 'Gas cupational Safety and Health Administration LIST OF ACRONYMS (Continued)

OSWER Office of Solid Waste and Emergency Response PA Preliminary Assessment PAH Polynuclear Aromatic Hydro (a.k.a. Polyaronatic Hydrocarbon and P Aromatic Hydrocarbon) ppm Parts per million ppb Parts per billion PRP Potentially responsible party QAPP Quality Assurance Project Plan QA/QC Quality assurance an^ qualTty-^ontrol RAS Routine analytical sei RCRA Resource Conservation covery Act RD Remedial Design RfD Reference dose RI/FS Remedial/lnvestigation/Feasibility Study ROD Recor^of^ DetzisionN^.^ RPM Remedial Project Meager SARA Superfund Amenoin^nts and Reauthorization Act, 1986 SAS Special analytical services SDWA Safe Drinking Water Act SI Investigation SITE und innovative technology evaluation SOP rd operating procedures SOW 'tement pf Work

XI LIST OF ACRONYMS (Continued)

SPCC Spill Prevention Control and Countermeasure SPDES State Pollution Discharge Elimination System SPHEM Superfund Public Health Evaluation/M^ual SWDA Solid Waste Disposal Act TAT Technical Assistance Team TBC To be considered TCL Target compound list TDM Technical directive memorandum TLV Threshold limit valu TSCA Toxic Substances ContjfoiTXct 1' VTAOT VT Agency of Transportation ' VTDEC VT Department of EnviroruMmt^l Control ,

Xll EXECUTIVE SUMMARY

INTRODUCTION

The Pine Street Canal Site Remedial Investigation (RI) was conducted under U.S. Environmental Protection Ag< (EPA) Work Assignment Number 10-1L19. The site is locj northwest Vermont, about one mile south of the centi te city of Burlington, along the shore of Lake Cham^ The site encompasses an 80 acre area, is owned by severa: nies and individuals (along with the State of Vermont and tl City of Burlington), and contains several active businesses at the northern and southern ends of the site. In the past, the site contained sawmills and lumber yards builder and coal yard, A manufactured gas plant (MGP) was he middle of the site on Pine Street. Heating and 1 'was produced from coal and oil at the plant between 19^8 d 1966. A canal and turning basin within the central portion\o the site was used for waste disposal, along with other areas of he site. The site was investigated by EPA and placed on the National Priorities List due to the presence of slic^ inNLake Champlain traceable to the site and extremely high L^els]of-—volatile and polycyclic aromatic hydrocarbons (PAH)/ jsi /soils ^tid groundwater. Remedial Investigation monitoring wa^performed in 1989 and 1990 throughout the site and in Lake Chamtelai^

OBJECTIVES

The this RI to:

he geology and hydrogeology of the site, the severity and extent of soil, sediment, er, surface water, fish, and air contamination. Evaluate existing and potential risks to public health and to the environment, and

ES-1 o Provide information to support a comprehensive ^n^ybi^ of remedial alternatives.

FIELD INVESTIGATIONS

Data presented in the Pine Street Canal RI repq ere collected during the following field activities:

o Magnetic, conductivity, and ground ing radar surveys; Ambient air investigations, including the analysis of nine samples for volatile organics and PAHs; Surface water sampling frop~.4^ie site and Lake Champlain (29 samples),

o Sediment sampling (28 samp o A soil gas survey. o Surface soil sampling (29 sa s, plus six special samples for dioxin analysis), Subsurface soil pling involving the collection of 113 samples from ngs and 10 monitoring wells, Groundwater i^nvolving the collection of 58 samples fr stalled in ten well clusters, along with 11s,

o Rising head slu in twelve wells. o Ecological investigations, including wetlands delineation, population surveys, biota sampling, and analysis of chemicals in fish.

ion and handling was conducted in accordance roved methods. All analyses were performed Contract Laboratory Program (CLP)'.

ES-2 MAJOR FINDINGS

The major sources of both organic and inorganic contc at the Pine Street Canal Site are process residues from operation of the manufactured gas plant. Volatile organics (benzene, toluene, ethylbenzene, xylenes), semivolatiles (mostly 2-6 ring PAHs), and inorganics (metals and cyanide) associate^ with process wastes from coal gas manufacture are tg/uivi jBt^ various concentrations in different media over most ol

The major area of subsurface soil and groundwate^spoii^mination covers approximately 38 acres of the 80 acre site. cJi^olindwater, surface water, soils, sediment and air all exhibit some degree of contamination. The contamination appears to have resulted from common, historical practices of disR|z$sih9-..Qfprocess wastes on-site and in the back-waters of the w^l"toids an9"^rom day to day operations of the gas manufacturing pr^nt\pa.^C7^eaks, inefficient eguipment, improper maintenance).

RISK ASSESSMENT

A baseline risk asse^menr\ was conducted to identify compounds which could pose a siflTii/ican"r'"health threat. All data collected from air, soil and vatex. s^p^Tln^g v^re evaluated.

Results show that the\pri^ry contaminants of concern under current land-use are benzene >k4Sd cyanide in surface water and PAHs in soil and sediment. The maximum individual excess risk of cancer was 3x10' ermal contact and incidental ingestion of surface water fo rs swimming in the canal; and the risk under average^ Id be 3x10" The maximum individual excess risk o direct contact and associated incidental ingestion y trespassers was 7x10-6 .; and the risk under average exposu ould be 5x10• 7 The maximum hazard index would

ES-3 be 0.5 under maximum plausible exposure, due to inc ingestion of cyanide in surface water by trespassers swi: site.

For the assumed future use of the Pine Street Canal Site as a residential development, the highest risks were ^om the use of contaminated near-surface groundwater for potabl rposes. This produced a maximum individual probability of Cj ne and a hazard index of 34 for maximum plausible expo er average exposure, the maximum individual cancer risk wou %; and the hazard index would be 0.7. The water is visibly con€^H^nlrt:ed, and the use of this water as a drinking water source is highly unlikely.

Dermal contact with subsurface iîl bfot _ the surface as a result of such development and asôciâ^^ dental ingestion could result in a maximum excess cancer v( sk of 3% (for adult gardeners ) and a hazard index of 1.6 ( ihildren) under maximum plausible exposure. Under average exposur o the subsurface soil. J the risk of cancer from soil contact would be 9x10''; and the hazard index would be 0.007.

Under future proj enzene, PAH and cyanide would remain the principa f concern. However, exposure to beryllium, cadmium, c rm, bis(2-ethylhexyl) phthalate, and methylene chloride would a of some concern.

CONCLUSIONS

Based ,ults of the RI; significant soil, sediment, ground ,ace water contamination exists at the Pine Street Risks to human health from current and projected land-use are clearly unacceptable, and alternatives Id be evaluated to remediate these risks.

ES-4 Treatability studies would be useful to help evaluate pott applicable remedial technologies, and conteuninant modeling and ecological studies are recommended to help evaluate the tradeoffs between alternative remedial actions.

ES-5 1.0 INTRODUCTION

1.1 Purpose of the Remedial Investigation

The Remedial Investigation and Feasibility Study (RI/FS) process is the methodology that the U.S. Environm^n^l Protection Agency's Superfund program has developed for c. izing the nature and extent of risks posed by uncontrollted OUS waste sites and for evaluating potential remedial opt The purpose of this Remedial Investigation is to determine ture and extent of contamination originating from the former :n&Qdfactured gas plant (MGP) at the Pine Street Canal Site in Burlington, Vermont and to develop a baseline risk assessment to determine the potential hazards that the site pi'e&ents to the exposed human population. The U.S. EPA is the\ le^id^gerrcy^ responsible for conducting this remedial investigati

The Pine Street Canal Site has b^n \the focus of several previous investigations (Section 1.2.4) ano an Immediate Removal Action (IRA). These previous activities and studies have created a preliminary data base/of information conceming the nature and extent of possible co at the site. However, each of these investigation ted in scope or concentrated 'on only a certain segm^ e. This Remedial Investigation analyzes results of pre studies, identifies gaps in the existing data base. additional data requirements. gathers the additional data required, and integrates all data into proprehensive data base for the entire Pine Street formation is then used to determine the actual f contamination and its potential impact on r, it will be used to support the assessment ial alternatives necessary to remediate the

1-1 Major activities performed during the RI included: rc existing site information; review of local geologic an^ geologic information; installation of monitoring wells and borings; field sampling of suI^face water, biota, soils, sediments and ground water; conduct of geophysical surveys of subsurface conditions; conduct of a health risk assessment; and t^^ review and interpretation of analytical data.

This Remedial Investigation Report presefv findings of these activities as well as the assessment of risk ting from site conditions.

1.2 Site Background

This section summarizes info ning descriptive features of the site, history of the ctured gas plants (MGP) and previous investigations and s^di that have taken place on or near the site.

1.2.1 Site Description

The Pine street Ls an uncontrolled hazardous waste site located in the (Figure 1-1) at the northwest corner of Vermont al shore of Lake Champlain (Figure 1-2). It is located le city limits of Burlington, VT (Figure 1-3), less than one .f mile south of the center of the city. The site encompasses approximately an 80 acre area with Lake Champlain fopoing the westem boundary. Pine Street as the eastem boundary,/Lake^d^NAvenue as the southern boundary and the northern property^ line o^tne former UltraMar Petroleum Company as the northezTi. srfc^ bounpayy (Figure 1-4).

1-2 North

Pine Street Canal, Burlington, VT

GENERAL MAP OF NEW ENGLAND AREA FIG. 1-1 PINE STREET CANAL SITE

1-3 1-4 CITY OF BURLINGTON, VT FIG. 1-3 PINE STREET CANAL SITE

1-5 /TN s§sssssssssssssss nLBLmtis-mtcT I I •! I I I I I I I I I I

SCALE (FEET) 100 200 300 400

LAKE CHAMPLAIN

SITE LOCATION MAP FIG 1-4 PINE STREET CANAL SITE

1-6 There are several active businesses at the norths southern ends of the site and along both sides of Pine StrC central portion of the site is a 30 acre section that contains a barge canal and turning basin, open fields with common shrubs, grasses and deciduous trees, and wetlands. The Vennont Railroad has two train tracks that run north and south n embankment between the canal and Lake Champlain. The s has been subjected to random filling throughout its hi 11ing has taken place principally from the north, east an perimeters of the site resulting in a low, uneven topography si enerally towards the canal. Surface drainage is poorly developbd^and much of the interior of the site is marshy lowland and wetlands. Surface elevations range from 107.5 feet above mean sea level (MSL) at Pine Street to approximately 97. MSL at the canal. The average water level for Lake Ch feet edjove MSL, however, this level fluctuates seasorii e highest levels usually occurring in the spring. The is connected directly to Lake Champlain and reflects the same r level and changes. Flooding is common, especially during the "Spring thaw, when much of the site is under water (Figure 1-5).

Two storm/sewer ty onto the site. The General Electric Company di act cooling water from three outfalls at its easte erty line and one outfall discharges into the southem end of al. Two drainage ditches that run east-west on the site appear^^o receive surface runoff from Pine Street. The Maltex Pond near the center of the site is a swampy area where thA-47.S. EPA conducted an Immediate Removal Action of approximately-SOO tons of soil. A berm was placed between the pond and the/Carfal, and vegetation consisting mostly of phragmites has reestab']

1-7 PINE STREET CANAL SITE TOPOGRAPHIC MAP FIGURE 1-5

IOW/Q

1-8 1.2.2 Site History

The Pine Street Canal site has been an industrial area for as^ long as records have been kept. The barge canal and turning basin were constructed in the mid-1800's to provide access to several sawmills, lumber yards, a boat builder and a coaly^rd. (Versar, 1988). The railroad embanJcment and railings appftrei}^ly predate the construction of the canal. (Alliance, 1987)

A coal gasification plant (i.e., manufactured^^s^plant) that produced heating and lighting gas for the Burlington atêar operated on the site from around 1908 until 1966. Process wastes, including coal tar, were routinely disposed of, or leaked into, low marshy areas around the plant and into the/can^l itself. Wood chips and iron filings used in scmibber Mier.a^ôns-~-wê also commonly disposed of on-site. As the gas plant\eâitde5t^ it produced gas mainly by the carburetted water gas (CWG) process, although it is unclear exactly when the plant switched\to\this type of operation and whether it used this process exclusive!^. In the early 1920's, a new, larger gas holder was built and one of the former gas holders was converted •be^'a'^êl oil holder. It is reported, but undocumented, that a LargOaiilLl^k (approximately 20,000 gallons) occurred from this tanl<^ 7ne>-«l2m^ was demolished in 1967.

The property now owfted bysGeneral Electric contains a landfill that began operation in th^/late 1800's. Aerial photographs indicate that the northern extent of General Electric's property was at one time marshy lowland that has since been filled-in. Various other pa^s of the site have also been used for a brush fiber manufacturing iplant, helicopter manufacturing, transportation equipment s^rage,) sawmills and lumber yards, a soft drink bottling plant, as^>lnaltNperrc>leum storage, and for construction debris and

1-9 fly ash disposal. Many active businesses still remain they will be discussed in Section 3.1.7.

Access to the site is largely unrestricted except for fences that surround some current businesses and warning signs stating that the area is a Superfund Hazardous Waste Site, y^^le 1-1 lists the chronology of activities taking place at the yPipte S;treet Canal Site.

1.2.3 Coal Gasification at Manufactured Gas P

The United States, during the 1800's and early 1900's, was heavily dependent for its lighting and heating needs on gas derived from fossel fuels produced by manufagttir^ gas plants (MGP). Three major processes were used to manuf<

o Coal carbonization (CC) o Water gas and/or carbure water gas (CWG) o Oil gasification

The Burlington Gas Plant at Pine Street operated under various names and own until 1966. The principal gas producing process e MGP was the water gas and/or carburetted water gas'

1.2.3.1 Process Descriptid^

Water gas (blue gas) is produced by passing steam through a bed of p form a gas composed of equal quantities of carbon hydrogen. This gas has a low heating value (300 B and is non-luminous due to a lack of rich hydrocarbd at treatment of coke or oil to produce gas was known as gasi on, whereas carbonization referred to the heat

1-10 TABLE 1-1 SITE REMEDIAL CHRONOLOGY FOR TEE FINE STREET CANAL SITE* BURLINGTON, VERMONT

Action Date

Burlington Gas Works moved to location on Pine Street and began to produce manufactured gas Large amount of potentially contaminated 1944 clay was excavated from the floors of the current GE Facility, and replaced by concrete flooring. Sludge, a by-product of the coal 1949 - 1966 gasification process, was sold to roofing & asphalt dealers. GE was disposing of potentially - 1967 hazardous wastes, in what officials think may be the north end of site. Army Corps of Engineers required GE clean up the area in 1979. Building Permit issued by city to April 1967 demolish all buildings/'^Tr^remises except gate station cvt Yerwpnt Gas Systems.

Investigation of oi ce. May 1, 1967 Free Press article stat 1 thought May 2, 1967 to have originated from oil depot.

Free Press article, after Interior May 6, 1967 Department_Jjivestigated the spill, concludedftha^^he spill was not from the oil/d*.

skewing demolition of May 29, 1967

* This chronoldgi^was compiled from a variety of sources including: PA/SI FIT Project Report, Pine Street Barge Canal Site Negotiation Support Document and Interviews by PEER Consultants.

1-11 TABLE 1-1 (Continued)

Action Date

Free Press article and picture of the July 14, 1967 fire in the foundation of the gas holder. Excavation for Burlington Electric 1967 Department headquarters. 20,000 cu yd of dirt removed, but no records of where it was disposed of. Westerb part of gas plant land sold by December\27/ 1967 the City to G. S. Blodgett. State investigated oil spills in the July 13, 1968 lake from the barge canal. Meetin held with landowners to discuss t: placement of a dike around the oi< installment of booms across the c to protect the lake. Request for equipment to dike Maltex Pond, but nothing significant done. Drainage ditch that had funneled oils and coal tar to the canal plugged. Coast Guard reported ng into the Lake and State n took place. A Vermont Association porta m was installed acros buth of the Canal to stem the fl into the Lake. Geology students from University of March 1971 Vermont studied oil contamination at Pine Street—sLite. They made an appeal to the State Attorney General for action y y€riiojit\)epartment of Water

1-12 TABLE 1-1 (Continued)

Action Date

launched an investigation of sewer outfall and public or private drains emptying into the canal. State meeting called to discuss the problems of Pine Street Site. Former E.B. and A.C. Whiting building demolished. Additional filling had taken place on Whiting property. An earthen dike was constructed on the western edge of the fill area, and area was no longer under water. Coast Guard notified EPA of oil rele ary 17, 1975 associated with warm weather. Fede funds used to remove approximately 1,000 gallons of oil. EPA notified Maltex Company owners of April 1, 1975 Federal Water Pollution Control Act liability. Large dike built aroun Between October, 1975 and April, 1978 Zinc, lead, cadmium, lyses 1977 - 1978 of the sludge perfo ng atomic absorption (AA) but inconclusive. Vermont AOT conducted soil borings. 1977 - 1978 Estimated that 150,000 - 200,000 cubic yards of jcontaoiinated material would have to/be reino\^ed. Vermont/A05 oordinated in 1978 - 1980 develi r evaluating and remedial e relating to the developmei proposed right of way. Indue bmittal of a draft Environmental pact statement.

1-13 TABLE 1-1 (Continued)

Action Date

Vermont DEC sampled water in the canal May 1981 and basin. EPA first visited site. Hazardous Ranking System used; site scored for inclusion on NPL National Priorities Listing of site; Nove Ranked 88th, Vermont's top priority Superfund site. Vermont DEC evaluated technology for Late 1981, early remediating the site including 1982 encapsulation and solidification, sealing the canal around the sit E.C. Jordan report of the site investigation discussed available remediation technology and concluded that additional geotechnical, hydrogeologic, and environmental sampling investigations were required. Preliminary Assessment/ Report issued June Investigation (PA/SI 1982 Ecology & Environme Vermont AOT initiate fined August 1982 to proposed right o Analytical data confirmed tl^e ptesence 1983 of organic compounds. Joroari proposed groundwater withdrawal system. Two pump tests-performed to test July 1983 feasibility of groundwater withdrawal system

1-14 TABLE 1-1 (Continued) Action

Burlington Southem Connector - Pine January 1984 Street Canal Site. Vermont Agency of Environmental Conservation Permit Application for Remedial Action and Highway Construction prepared by Perkins Jordan.

Maltex Pond - Immediate removal action December by EPA Region I. PRPs were notified of EPA's intention to April 19 perform an RI/FS of the site. Versar subcontracted to prepare a July 1987 negotiations support document to outline specific tests and regul guidelines to which an RI/FS for site would need to conform. Southern Connector & Subsurface June 1988 Contamination Search. Wiesner Property and St. Johnsbury February 1989 Trucking sites subsurface Contamination Delineatio»...^urvey U.S. EPA Work Assignme^ ^L19 June 27, 1988 issued to REM VI ondubt. RI/FS at Pine Street Ca Submittal of final RI/ March 20, 1989 documents to EPA.

Public Meeting, U.S. EPA, REM'^I team March 31, 1989 members and public. RI Field A les began —^ REM VI. April 24, 1989 Draft R mpling Visit Report Report Issued May GE F gton, VT, RCRA 1989 Facil Subsurface tion, Blodgett Oven Report Issued July Company, Inc; ^epared by Aquatec, 1989 Inc. Summary of Environmental Sampling at GE Report Issued Company Burlington Facility prepared October 1989 by Wehran Engineering.

1-15 treatment of coal. Because manufactured gas was used main lighting in the 1800s, it was necessary to "enrich** wa usually by the addition of gas produced from the cracking^^of (oil gas) to form carburetted water gas (CWG).

The craclcing was achieved by spraying oil v a carburetor onto hot brickwork or onto a bed of selected St. The oil gas, having a higher heating value (1700 B' oot) and hydrocarbon content than water gas, results as mixture comparable to coal gas (in terms of heating luminating values). Figure 1-9 illustrates the set-up a > typical Carburetted Water-Gas Plant. Figures 1-6 through 1-8" show the typical run cycle of a CWG plant. The carburetted water gas was also amenable to the same purific9.ôn processes as coal gas although less coke, tar and ammoni^ was lijced as compared to coal gas. Table 1-2 shows the diffe ^tar constituents between the coal carbonization (coke 'ând water gas (Curgi Gasifier) processes. Carburetted water asNêcame the predominant form of gas production in the U.S. and IS produced until the demise of the manufactured gas industry.

1.2.3.2 Process Resi

All three manu cesses produced residuals that reguired some form of ent. Table 1-3 shows the process residuals that can be exp from different manufactured gas plants.

Six mi ical classes have been identified as predominant in the iduals although not all six classes are associ h process. Table 1-4 illustrates the predomina^ classes in process residuals, from MGP depending on bcess employed.

1-16 eowaumoN r Moeucra TO WASTE HEAT lOtLCR

AMM 1 l^\ t »

OENERATOR CAMURETOH •UPEHHEATER

BLOW, TO HEAT APPARATUS 21fi)t< Xlir !• blown through th* eok* b*d to b*«t tb* b*d. Air •nt*rs from th* bottoa ef th* b«d *nd flovs upward through th* cole*. Air Is ad&ifE%*d„to th* top ef tb* carburator, then i t bums carbon Bonoxta»>lAth* gas froa th* 9«narator, supplying aSdditLajial bait-~,^.(or tb* ehackarbricJcs. Tb* gasas flay dmftwanl throu&b tb* carburator, than upward throogta lh* «nparoaatt*^^Vif 111 ng froM th* top of th* suparbaatar v>d Uevlog to a wast* haac beUar.

AMI IN-

BLOVMtUN Tbis v*t, ef tb* cyels cellacts tb* earb«»> rich gaa frea tba ^anaracer bad and adds it ta gas. Tb« air flow is tha saa* as that duriag axcape ne air is addad at th* top of tb* and th* gas** ar* roatad through th* vashbeot aaias. SOURC^H{.S. ^DUCtlO N OF MANUFACTURED GASES

CYCLES OFF^ A-CARBURETTEW D WATER-GAS (CWG) SYSTEM FIG. 1-6 PINE STREET CANAL SITE

1-17 UP RUN SS=23in: During tha up-run, staaa is admitted te tba bai of th* ganarator, flows upward through tha b*d ef incandaacent coXa (forming blua gas), out tha top of tha ganarator to tha top of tha carburator (whara oil is sprayad into tha gas and onto tha checlcarbrielc, eracUitg tha hydrocarbona), down through tha carburator, upward through tha suparbaatar (whara additional craclcing ef tb* hydrocarbona occur), and out ttcQugb tha top of tb* suparhaatar and washbox to tha V^* BaltRB.v.During tb* up- run, tha bottom of tha colca b^d coola faatacthan does th* top. ^

PNOOUCTOM TOWASHMX

•TEAU

Down-run; Tb* dcnrt-raa (or back-run) is identical to tha up-run axcapt th^xyitaaa ia introduced at th* top of th* ganarator bad, flows down through tha bad, and tb«a to th* top of th* carburator. Tha top of tbe bed is cool ad during tha down-run, maintaining a hot area ia tb* cantar of tha bad. Mora efficient operation of th* rator la obtained with split runs (up and down) than antir* run ware performed in the same direction.

SOURC OF MANUFACTURED GASES N, V / CYCLES OF>i

1-18 <»• MOOUCTC TOWASHSOX

AIR PURGE

Air purtTgj The ai, actually starts the blov, but gas from the supe ent to the gas mains. This purges the appa Btu gases and recovers them as part of<

SOURCE: U:S* PROQUOTION OF MANUFACTURED GASES

CYCLES OF A CARBURETTES D WATER-GAS (CWG) SYSTEM FIG. 1-8 PINE STREET CANAL SITE

1-19 FUEL STORAGE

GENERATOR

OIL STORAGE

STACK -4 TAR SEPARATOR

WATER TAR WELL CONDENSER

INLET DRIP MARKET OUTLET DRIP

T^jTB^rn^Ton

fIFlERS

STATION METER STORAGE HOLDER FUEL OR GAS

AIR OR MAINS WATER GASES

WATER OR TAR SOURCE: STEAM FLOWCHARTFOR A CARBURETTED WATER-GAS PLANT FIG. 1-9 PINE STREET CANAL SITE

1-20 TABLE 1-2 COAL-TAR CONSTITUENTS (%)

Coke Oven Lurai Gasifier

Acenapthalene Anthracene Benzene Carbazole o-Cresol m-Cresol p-Cresol Diphenylene oxide Ethylbenzene Fluorene High-boiling tar acids Medium-soft pitch a-Methylnaphthalene b-Methylnapthalene Naphtha Naphthalene Phenanthrene Phenol Styrene Tar Bases Toluene o-Xylene m-Xylene p-Xylene Xylenols

Source: J.D. Enzminger

1-21 TABLE 1-3 PROCESS RESIDUALS FROM MANUFACTURED GAS PLANT

COAL CARBURETTED PROCESS RESIDUALS CARBONIZATION WATER GAS OIL GAS

Coal Tar Oil Tar X Leunpblack X Tar/Oil/Water Emulsion X Tar Decanter Sludge X Ammonia Saturator Sludge X Acid/Caustic Hydrocarbon Treatment Sludges Wastewater Treatment Sludges Coke Ash X X Spent Oxide/Lime X X Sulfur Scrubber Blowdowns X X Ammonium Sulfate

••X** indicates resid by the process

Source: Management of M^timf^tured Gas Plant Sites, Gas Research Insti^iite, October, 1987

1-22 TABLE 1-4 PREDOMINANT CHEMICAL CLASSES PRESENT IK PROCESS FROM MANXTFACTURED GAS PLANTS

CHEMICAL CLASS

LIGHT INORG. IN0R6. PROCESS RESIDUAL PAHs AROMATICS Pi N S METAL

Coal Carbonization Process: Coal Tar X Hydrocarbon sludges*^^ X Wastewater treatment sludges X X X Coke X X X Ash X Spent oxide/lime and liquid scrubber blowdowns -> Carburetted Water Gas Process: Coal tar and oil tar X Tar/oil/water emulsion X Wastewater treatment sludges X X Ash X Spent oxide/lime and li scrubber blowdowns

Oil Gas Process: Oil tar Lampblack Tar/oil/water emulsion X Wastewater treatment sludge X X Ash X Spent oxide/lime and liquid scrxibber blowdowns

emical class is expected to be present in the proces onia saturator, and acid/caustic treatment sludge

Source: Managem^t of Manufactured Gas Plant Sites, Gas Research Institute, October, 1987.

1-23 The primary sources of organic contamination are from, tar, oils and tar/oil/water emulsions. Purifier wastes, con of iron-impregnated wood chips or spent lime, constit* primary source of inorganic contamination.

Tars and oils were produced as by-products from all three (coal gas, water gas, oil gas) production processes. Coal tar represents the most complex of the hydrocarbon byî«'odu6te because it contains the broadest spectrum of molecular weign^ônstituents. Carburetted water gas plants, such as the Pine Sbj:;eetsCanal Site, produced less tar, coke and ammonia as compa^^^>to coal carbonization gas and there was a general lack of phenols. While some plants could recover tars and oils and sell them (as fuel or to tar refiners), or use them on site, smaller gas plants often produced tars in insufficient quantitlestc^-âistify their recovery. This was particularly true of carbuisetêa>-waterâs plants where the tars were usually disposed of with\thk/wavste condensate at the plant "dump".

Carburetted water gas manufacturers produced tars that were usually less viscous and dense than were tars produced by coal carbonization. Therefo }e tars tend to be more mobile in the environment than mos ^t must be emphasized that the effect and characte iS wastes and their fate and transport depend on a s^any variables. Properties of tars differed depending on >were collected in the purification process. The heavier tars (md^t viscous and dense) condensed first. Benzene, toluene and other volatile organics were scrubbed from the ga:ig'~oi^-sCondensed as "drip oil." How the wastes were managed on-srE^>.hoW the site was dismantled and reused, and what local ^n\^45°'^™®""\*A conditions existed all contribute to redistributiolvand/possible physical and/or chemical alteration of wastes over Tsime. /

1-24 Estimates of the gross quantity of materials which ma^ been produced at a MGP are usually unreliable. Documentati, not exist regarding methods of waste management and what of wastes were managed off-site versus on-site to determine the accurate quantity of environmental wastes.

1.2.3.3 Polynuclear Aromatic Hydrocarbons

MGP residual process wastes, the main cont<^ift(Vpts/of concem at the Pine Street Canal Site, contain high cb^ceircrations of Polynuclear Aromatic Hydrocarbons (PAHs). PAHs ar^sdi^ributed throughout the world in soils, sediments and surface wat^s at low concentrations. On-site land disposal has been a common method for dealing with MGP residual process wastes. This practice has led to extensive soil and groundwater /contamination at a number of sites in the United States. This is^ p\^lifC hea^h concem since many compounds in coal tar, largely Vhev^PAiis, are carcinogens. PAHs are formed during the high temj^rature pyrolysis of hydrocarbons. Exceptionally high levels Qf/PAHs are found in the waste streams of high temperature industrial processes such as the thermal cracking of coalyors^troleum.

PAHs make up a/diverge grbup of several hundred organic compounds consisting^^ at/leastN;yD benzene rings. Sixteen PAHs are on the U.S. EPA pH^ri'ty pollutant list (Table 1-5). All sixteen are found in cokl. thr. Coal tar is an extremely heterogeneous substance containing thousands of compounds. Included in this mixture are,single ring aromatics, such as benzene and toluen^T arid. PAHs ranging from naphthalene (2 rings) to compounds''^witir"^5.0 rings or more. Pitch, the coal tar fraction remaining a^er difetillation up to 377'C, contains PAHs of four or more condfei^e^Nxinigsy Approximately fifty percent of the compounds in pitch contain more than seven rings.

1-25 TABLE 1-5 PHYSICAL AND CE2MZCAL PROPERTIES OF PAHs

Water Vapor Molecular Solubility Pressure Substance Rings Weight ng/1 (torr )

Naphthalene* 2 128 0.0492 Fluorene * 3 166 5.0X10 Acenaphthylene * 3 178 6.8X10' Phenanthrene * 3 178 6.8X10* Acenaphthene 3 178 Anthracene 3 J).070 1.9X10" 2-Methylphenanthrene 3

2-Chloronaphthalene 3 192\ Fluoranthene * 4 202 ^V <^0.260 6.0X10 -6 Pyrene * 4 202 0.135 6.8X10' Benz(a)anthracene * 228 0.014 1.0x10 Chrysene * 228 0.002 5.0x10' Benzo(a)pyrene * 252 0.0038 5.5x10 Benzo(g,h,i)perylene * 276 0.00020 1.0x10 -10 Benzo(b)fluoranthene* 252 0.0012 5.0X10' Benzo(k)fluoranthene* 252 0.00086 9.6X10 •11 Indeno(1,Z,3-cd)pyrene 276 0.062 1.0x20 '10 Dibenzoia.A) anthracene 278 0.0005 I.OXIO •10

XT? Pollutants * U.S. EPA Prion Source: Brown, et al.

1-26 1.2.4 Previous Investigations

Existing data for the Pine Street Canal Site were aVa^abl from several sources, including: the U.S. Environmental Protection Agency, Region I; Vermont Agency of Transportation (VT AOT); General Electric (GE) Company, Burlington Facility; Ultramar Petroleum, Inc.; Blodgett Oven Co.; and the Ve Agency of Environmental Conservation. Information was col om these and other sources prior to and during the RI formation gathered was used to develop the courses of actio: during the RI field activities.

The Vermont Agency of Transportation (VTAOT) drilled a series of eight borings in 1976 as part of an investigation for a proposed highway right-of-way to be constructe^-^tiuiiough the site. These borings were geologically described %nd>^^ logged but were not subjected to laboratory chemical analysis\/Th^^b^ings are located along the center line of the proposed IvUrh^y. The southem most boring (B-1) is approximately 100 feet nc(rt)i of Lakeside Avenue. The remainder of the borings are 400 feet^part in a north-south line through the site. Th^logs describe "organic material" being detected between eight /md_J2l\feet in borings B-2, B-3, B-4 and B-6 (Figure 1-10).

The series of envixonmental investigations that have been performed at the Pine Street C^al Site began with a Preliminary Assessment and Site Inspection (PA/SI) conducted by Ecology and Environment in 1982 for the U.S. EPA. Several of the investigati at followed the PA/SI focused on determining the feasibility acing the proposed right of way for the Burlington Southern c thorough the Pine Street Canal Site. Subsurface contamin gations were conducted for the Blodgett, Wiessner an hsbury Trucking companies on their respective

1-27 PINE STREET CANAL SITE SAMPLING LOCATIONS FROM PREVIOUS INVESTIGATIONS FIGURE 1-10

2 z m tn 3 3) m

8I 111 3 |S

o properties. Other investigations focused on GE and Ult^ama Petroleum properties. (Figure 1-10)

Previous investigations included extensive sampling of soil, surface water and ground water, but not all the investigations analyzed samples for the same chemical parameter^/^in the seune media. All samples collected were analyzed for compounds (VOCs). Ground water samples from the were analyzed for VOCs only. Soil samples from the Wiessner property were all tested for VOCs, them had extraction procedure toxicity analyses and ground water samples from the Wiessner investigation (six wells, MWl-6) were analyzed for VOCs and base/neutral (B/N) extractable compounds. The analyses pex^f^rmed for samples from the RCRA Facility Assessment (GE) were t ^ , base/neutral/ acid (B/N/A) extractables, pesticides/ Is. Parameters tested for in the Southern Connector rface contamination search conducted for the Vermont Agency o nsportation (VA AOT) were VOCs, base/neutral extractables. es/ PCBs, and metals.

There are three eas of contamination identified by the previous investigat ; the vicinity of the former coal gasification plan est of the coal gasification plant; and the canal c al eind turning basin). Other contaminated areas on-sit are more localized are the General Electric facility and St. Johi^ trucking company located at the southern boundary of the site, north of Lakeside Avenue; Blodgett property, north of Lakeside Avenue along Lake Champlain; Wiessner property, je^ff site, south of Lakeside Avenue; and Ultramar property Xl9"9 thfe\no^±hern side of the turning basin.

The VOCs has been identified as the site of the former coal plant. During the FIT investigation all

1-29 ground water samples in the vicinity of the gas plant contain excess of 500 parts per billion (ppb) benzene, tolue: ethylbenzene. The seunple results from the Burlington S Connector Report showed volatile organic compounds and base/neutral compounds (B/N compounds) at parts per million (ppm) levels west of the former coal gasification plant, close to theênter of the site. These results are for a series of seven brings; A2 - A8 (Figure 1-11). VOCs present were benzeneXat ^?^16 ppn; ethylbenzene at 9-180 ppm; and toluene at 4^2-3>^y ppm. B/N compounds identified included acenaphthene a<^^ 24r300 ppm; fluoranthene at 20-140 ppm; naphthalene at 240-1000 p|OTrênzo(a) anthracene at 12-83 ppm; benzo(b)pyrene at 10-49 ppm; 3Y4-benzo fluoranthene at 10-35 ppm; benzo(k)fluoranthene at 10-34 ppm; chrysene at 12-83 ppm; acenaphthylene at 10-170 ppm; anthracene at 95-740 ppm; fluorene at 33-180 ppm; at 96-740 ppm; and pyrene at 12-140 ppm. In boring' icides aldrin, dieldrin, and heptachlor were detected"^ ppb. Analytical results from a ground water sample fromN itoring well (MW) 105 (Figure 1-12), on the vest side of the gasification plant showed the VOCs dichloromethane at 7 ppb;' benzene at 1200 ppb; toluene at 37 ppb, and xylene at 3900 ppb. B/N compounds detected from MW105 included the/P;ui& naphthalene at 2800 ppb; acenaphthene at 59 ppb; and fluorene yrt lÔppb^^^^ These contaminants are known VOCs and PAHs associatedN^^h/coh^^jgasification residuals (Tables 1-2 and 1-4).

The wetlands include a llSw-lying area at the center of the site, a large portion of the south end of the canal, and Maltex pond. In a-'seFies of borings at the wetlands area, ground water samples dra6. ^^ek wells all showed benzene, toluene, and ethylbe||{zei^ in excess of 500 ppb. Groundwater samples taken during the,^^Bih::ling'ton Southern Connector Permit Application for Remedial Actton, and/kighway Construction site investigations were

1-30 N I i ! i i ! I § S I 8 § I 8 8 § I 0 §§§§§§§§§§§§§§§§§ ajuRHSTJiEFr

M locMtooi tra ippfQdRMt

BURONGTON SOUTHERN CONNECTOR VERMONT AOT BORING A2.A9 LOCATIONS FIG. 1-11 PINE STREET CANAL SITE

1-31 N iiii § § § § I I I I

SCALE (FEET) 100 200 300 400

PREVIOUS ^ INVESTIGATION WELLS

LAKE CHAMPLAIN

BURLINGTON S OUTH^R N CONNECTOR PERMIT APPLICATION ROUNDWATER SAMPLE LOCATIONS GRO FIG. 1-12 PINE STREET CANAL SITE

1-32 from wells 104A, 104B (located to the west of Burlington Ele; Company), and 102 (located along the east side of the can the barge slip). Contaminants detected in 104A and 104B in^ dichloromethane at 4-17 ppb; chloroform at 1-21 ppb; benzene at 8 100 ppb; toluene at 16-160 ppb; ethylbenzene at 14-340 ppb; xylenes at 100-340 ppb; naphthalene at 21-750 ppb; acenaphtt^ne at 11-21 ppb; acenaphthylene at 28-43 ppb; fluorene at 30 pp]^(104A only); and anthracene at 19-46 ppb. Contzuninants deteote^T inûe ground water from monitoring well 102 were benzene a'bs^90Q/ppo; toluene at 6500 ppb; ethylbenzene at 3400 ppb; xylenebsat\5700 ppb; naphthalene at 710,000 ppb; acenaphthene at l2<),obo ppb; acenaphthylene at 88,000 ppb; fluorene at 28,000 ppb; anthracene at 330,000 ppb; fluoranthene at 84,000 ppb; pyrene at 110,000 ppb; chrysene at 76,000 ppb; benzo(b) fluojc^nthene at 19,000 ppb; and benzo(a)pyrene at 20,000 ppb (Figur^1-12)^^—iQMaltex pond a tar sample was taken in 3 fractions. In\fracoon l7?100% aliphatics was detected. In fraction 2, contaminakrtsôund were naphthalenes (methyl) at 81 ppm; naphthalenes (Viii^thyl) at 360 ppm; naphthalenes (trimethyl) at 371 ppm; fluorôjes (C-16 series) at 49 ppm; fluorenes (methyl) at 138 ppm; phenanthrenes (C-18 series) at 75 ppm; phenanthrenes (me^ at 53 ppm; phenanthrenes (dimethyl) at 107 ppm, phenanthr |imethyl) at 65 ppm; pyrenes (C-22 series) at 27 ppm; 138 ppm. In fraction 3, contaminants found (C-16 series) at 15 ppm, fluorenes (methyl) at 41 phenanthrenes (C-18 series) at 133 ppm; phenanthrenes (methyl) 55 ppm; phenanthrenes (dimethyl) at 180 ppm; phenanthrenes (trimethyl) at 98 ppm; pyrenes (C-22 series) at 109 ppm; pyrenes

Samp e canal and turning basin indicated above background 1 f volatile and B/N compounds. Surface water

1-33 samples taken from the canal, during the FIT project, contain excess of 500 ppb, total benzene, toluene and ethylbenze: series of nine sediment samples were analyzed from the cana the turning basin. Volatile and base/neutral extractable compounds associated with coal tars were found in the canal and at the location where the turning basin discharges into Champlain. These compounds were detected from samples S1-: Total VOC concentrations ranged from 5 to 2,089 ppb, neutral compounds ranged from 5780 ppb to 77,000 ppb. P s present in the turning basin at a concentration of 210 ppb further confirmed vith three additional sediment samples fro: basin vith concentrations of 1,500, 3,200 and 1,800 ppb total PCBs. Aqueous samples collected during the FIT investigation in the canal and turning basin showed traces of phtljalate esters, substituted anthracenes, and "saturated hydrocarpons;"^'""Sril^jwere less than 10 ppb.

Sampling was performed at General Ele Company, Burlington facility, for a RCRA facility investig on of releases of hazardous constituents. Four borings were completed in the Old Landfill, at the north General Electric property. Soil samples from boring #7 visible coal tar. Analytical results showed trichla ; benzene at 19 ppb; toluene at 70 ppb; ethylbenze nd total xylenes at 43 ppb. Soil samples from boring carbon disulfide at 2 ppb; trichloroethene at 15 ppb; 1,2-dichloroethene at 26 ppb; benzene at 2 ppb; toluene at 5 ppb; ethylbenzene at 8 ppb and total xylenes at 69 ppb (Figures 1-13, 1-14).

In from boring #2, minor amounts (<5 ppb) of benzene, benzene, and xylene were detected. The PCB, Aroclor- ted at 810 ppb. Ground water samples from these boring ntained 1,2-dichloroethene at 45 to 90 ppb.

1-34 N I I § I I I I § 8 8 8 8 8 8 8 I § (T ) SSSSSSS8S8SSS8SS8 ^ ^ I I I I I I I I I I I I I I I I I SCALE (FgT) 100 200 300 400 PT.|

UVKE CHAMPLAIN

X77^ RCRA FACI:lbTYAS(L sSESSMENT - SAMPLING LOCATIONS FIG. 1-13 PINE STREET CANAL SITE

1-35 ^ N § I I i I ! I 8 8 I 8 8 8 8 8 8 8 /T\ S8888S88888888S88 nMMItTltttT t i I I I I I M I I I II I I I

SCALJE(FgT)

100 200 300 400

LAJ

SUMMARYOF/ENVIRONMENTAL SAMPLING AT THE GE COMPANY, BURLINGTON FACILITY. SAMPLE LOCATIONS. FIG. 1-14 PINE STREET CANAL SITE

1-36 In borings #2 and 4, trichloroethene in the ground water than 5 ppb MCL was detected. Benzene was also detec; concentrations exceeding the 5 ppb MCL in all borings ( 1-13, 1-14).

The other area of contamination on General Electric property found during this sampling study vas boring #5 at ^^old gas pump #2, along the eastem edge of facility prope^ alytical results indicated a concentration of 1,2-dichlo] t 12 ppb; PCB, Aroclor-1254 at 3256 ppb; and copper at 90 pp) res 1-13, 1-14).

Ultramar Petrolevim, Inc. is located along the northern boundary of the turning basin. Analytical results of soil sampling show typical motor fuel contaminatioi/witn^aftges of benzene at 13 630 ppb; toluene at 240-970 ppb; ethylbeH^el^ at^;8o-1600 ppb; and xylenes at 1000-9900 ppb. Other VOCs found^were chloroform at 680 1700 ppb and methylene chloride at \45tK)-6000 ppb. B/N/A extractables ranged from 240 ppb (MW-5) toy47610 ppb (SB-1). SB 1 was the most contaminated location while MW-5 was the least. The ground water sample from^J4W^ contained 1000 ppb of benzene and total volatiles of 7500/pBbx(F!|.gure 1-15).

Other areas of nclude areas of the Wiessner property, a paint-lacque facility located south of Lakeside Avenue. On the Wiessner px^ y, test pits were excavated to a depth of five feet, and visually observed. Three soil samples were collected; two had EP toxicity analyses. All three were tested for VOCs. In $KldItibn to the test pits, soil borings were completed through t>{e/iSuitdingXfoundation slab, but only visual observations occurre^. \North ^f ^Lakeside Avenue, six monitoring wells were installea^a^on^stha/lyLght of way near and on St. Johnsbury trucking property (Figure I7I6).

1-37 N I i I I i ! I 8 8 8 8 8 8 8 8 § 8 /T^ 888S888SS8SSSS8SS aMmHSTnaT I I I I I I I I I I I I I

SCALE (FEET)

100 200 300 400 r J. I ilKUl OCFT. ^-^njB.on.'

^ ^ [=3 =d]'

U\KE CHAMPLMN TURNMOtUM

ULTft^MABtPETROLEUM, INCORPORATED ENVIRONMENTStTE ASSESSMENT SAMPLE LOCATIONS FIG. 1-15 PINE STREET CANAL SITE

1-38 N I 8 8 8 §18818888888 8 8 8 8 888888888888 lOLMmMfnmtT (D Illl I I I I I I I I I I I I

SCALE (FEET)

WIESSNER PROPERTY AND ST. JOHNSBURY TRUCKING SITES SUBSURFAOEHNVESTIGATION. SAMPLE LOCATIONS FIG. 1-16 PINE STREET CANAL SITE

1-39 The soil samples analyzed in the test pits had detec levels of ethylbenzene at 34 ppm; total xylenes at 250-140^ and in AS-19-SS-1 only, methyl cyclohexane at 3100 ppb (F' 1-16).

Of the subsurface soil samples analyzed from no of Lakeside Avenue, MW-2 and MW-6 had detectable levels of VO; 's y6f jnethylene chloride at 63 ppb, acetone at 100 ppb, and nts of benzene and toluene (<5 ppb). Base/neutral c pound found in monitoring wells 1, 2, 5, and 6 were fluoranthen*. atN410 ppb, benzo (a) pyrene at 330 ppb, pyrene at 390 ppb, phenanthr^e 4t 2300 ppb, and naphthalene at 970 ppb (Figure 1-16).

Sampling conducted during the subsua^face investigation for the Blodgett Oven Company located wear ofthe-^^^neral Electric facility, north of Lakeside AvenueX i^ctptde4,^^our subsurface borings with wells. These wells are locatedyOn Blodgett property adjacent to the west side of the railroadVtracks. Analytical results of the samples indicate that on^/sample (MW-2-15-17) contained trace amounts of phenanthrene, anthracene, pyrene and carbon disulfide (Figure Appendix H contains maps of locations and concentra available previous investigation data. The maps includ ell as previous data. There are six maps included^ are soil data, one each for BTEXs, Carcinogenic PAHs, PAHs. The remaining three are water samples for BTEX, Care nic PAHs and Total PAHs.

1.3 Remedial InvestiQat3,on Summary

On the U.S. EPA issued Work Assignment No. 10 1L19 to the , under Contract No. 68-01-7448, to perform an RI/FS at treet Canal Site.

1-40 N 11111118 8 18 8 8 8 8 8 8 88888888888888888 (XaURWSTRffT

BLODSETT OVEN COMPANY, INC. SUBSURFACfe/NVESTIGATION SAMPLE LOCATIONS FIG. 1-17 PINE STREET CANAL SITE

1-41 Preliminary activities included the collection and integx) of existing data, an initial site visit, and the preparati Work Plan, Field Operations Plan and other supporting doc Final organizational documents were accepted by the U.S. EPA on March 20, 1989 and a public meeting was held in Burlington on March 31, 1989. Attending the meeting were representatiyeiS of the EPA Region I; REM VI staff, including the Pine Canal Site Manager; and concerned citizens of the Burlingto lans for the conduct of the Remedial Investigation 'ented and discussed and questions from the public were answe*

Site field activities began on April 24, 1989. Geophysical surveys and a soil gas survey were conducted over the entire site. These surveys were used as quick efficient methods of characterizing the entire site, ind of concern, and previewing subsurface conditions. Du r and winter of 1989, field teams collected samples fri bus media throughout the site. Surface water and sediment sa were collected from on-site drainage areas, the canal and Lake !mplain. A biological study was conducted to characterize the wetlands and the flora and fauna present on site, pnmental air sampling was conducted before and during site ^t^ such as drilling to determine if there would be any pro^ issions caused by disturbing the soil. Surface so ed from locations established by a rectangular grid (wl foot intersections) to provide an unbiased sampling of the si The final major field activities were the installation ' of monitoring wells, the collection of subsurface soil samples from borings and wells and the collection of ground Vater Samples from all wells on-site (both previously installed/we!llskQd\ells constructed by the REM VI staff.

1-42 All sampling activities were focused on filling gaps irtv existing data to provide sufficient information to completeAheM: N^^^ and fully characterize the site. N. ^

In a parallel process, work was begun on the Feasibility Study portion of the RI/FS, starting with a preliminatv review of applicable and feasible technologies for site remediation. Once analytical data on the samples were received, thi^ >were validated and integrated with the existing data to crea%e eNco^lete and comprehensive data base. This data base provides ^le ih^rmation to determine the extent and concentrations of contaminaiits,^nd the effect any contamination present may have on the health and welfare of the public and the environment, and to support a comprehensive analysis of possible remedial alterna^^is^es.

1.4 Overview of Remedial Investigati

This Remedial Investigation (RI) NyRebort represents the compilation and integration of all activiti6;^conducted during the Remedial Investigation. The report consists of the following:

Section 2.0 Investigation - This section describes f and methodology associated with site cK

Section 3.0 - Phvslcai! Characteristics of Site - This section presents the results of field activities and describes the physical characteristics of the site as by these activities.

- Nature and Extent of Contamination - This Qi^cusses the laboratory chemical• analysis the various sampling efforts.

1-43 Section 5.0 - Contaminant Fate and Transport section discusses potential routes of migration, contaminant persistence in the environment contaminant migration.

Section 6.0 - Baseline Risk Assessment ^ Health and environmental risks are determined in th ection based on study results. Chemicals of conce tified, the exposure and toxicity assessment ained and risk characterizations for current and land use are discussed.

Section 7.0 - Summary and Conclusions - This section summarizes the findings and exclusions of the RI report.

1-44 2.0 STUDY AREA INVESTIGATION

This section discusses field activities and methodologi' were performed as part of the site characterization. These activities included the mapping of surface features and geophysical, air, surface water, sediment, soil, groundwater and ecological sampling.

2.1 Surface Features

Field activities and methodologies associated wi^h tHb^mapping of surface features are presented in the following para^z^phs.

2.1.1 Objectives and Methodologies

Prior to the commencement of sam es, topographic mapping of the site was initiated, purpose of this initial survey work was to establish a ngular grid over the site area. A north-south, east-west th lines spaced 100 feet apart was surveyed, using Pine Street as the base line. Each intersection was surveyed_for elevation as well as horizontal displacement. A wooden stake was driven into the ground to mark each transect, tem allowed sampling locations and site features t located spacially. It was particularly useful dux^ B geophysical surveys when the need for straight evenly space was critical. The survey also allowed the calculation of the^area of the site.

After ailrt.1 new monitoring wells were installed, the survey team retuj^n^ e site and the new wells were surveyed in. Three bencM r\the City of Burlington were located and all survey verted to the State of Vermont Latitude

2-1 Longitude System. Existing wells were resurveyed to compa previous survey results. Additional points were surve; establish better control of contour lines. Locations of bui drainage features, rubble piles, sewer/storm drain outfalls and other physical features of the site were noted and recorded. A staff gauge vas placed in the canal to measure the seasonal change of water levels in the canal. A small boat vas eiq>^yed to take vater depth measurements in the canal and tuming/z>asfh;^ Field biologists recorded vegetation types and locati^nsS^o^s^e.

2.2 Geophysical Investigations

Field activities and methodologies involving electromagnetic and ground penetrating radar surveys of the site are presented in the following paragraphs.

2.2.1 Objectives and Methodologies

Geophysical surveys were conducted o^c^ the site as a quick and efficient method of delineating subsurface features and contaminant plumes and i;ien^ifying the location of any buried metallic objects.

The geophysical consisted of total magnetic field and magnetic gra terrain conductivity, and ground penetrating radar surveys, d penetrating radar was found to be of only limited e ffectivene s due to high conductivity at the site.

gradiometer portion of the magnetic survey ff at 4 feet 5-3/4 inches and 9 feet 3/4 evel. Magnetic data were collected at 847

2-2 stations at the site. Stations were located every 20 feet north-south lines; these lines were spaced 50 feet apax^, in the vicinity of the former coal gasification plant whe spacings of 25 feet were used. All data were corrected to the first base value taken on the first day of the survey.

Terrain conductivity data vere collected at th e locations as the magnetic survey, except in those areas not urveyed and/or too thickly overgrown to maneuver the ty unit. "Background" conductivity data were collected fr allpark on Pine Street near the St. Johnsbury Trucking Company

2.2.2 Survey Ecjuipment

The antenna for the ground pene adar survey was towed by hand near the former coal gasifica 120 MHz antenna was selected and adjusted for a maxii^ ion depth of 20 feet after several test profiles were using both a 120 MHz antenna and a 300 MHz antenna.

The magnetic survey conducted using an EG&G Model G856 Proton Precession Portab^ etometer with a gradiometer option. This is a microproces d instrument with a resolution and accuracy of 0.1

The terrain conductivrty survey was measured along profiles using a Geonics EM31-DL terrain conductivity meter. This is an induction type unit that measures terrain conductivity without ground electrcdesvor contact. The unit has a resolution of 2% of full scal^ aTcd~~an abcuracy of 1 mmho/meter.

2-3 A Geophysical Survey Systems, Inc., Model SIR1-- 3 m!X>und penetrating radar system was used to conduct the ground penettalflM N^^ radar survey. ^ ^ N. \V

2.3 Air Investigation

The following paragraphs describe field activiji^i^ and discuss methodologies involved in site air monitoring ac;!

2.3.1 Objectives and Methodologies

Ambient air investigations were conducted at the Pine Street Canal Site to ensure safe working conditions during RI field activities and to measure releases from the site as an aid in evaluating risk to the local popu^tiorrr---,5eal time personnel monitoring was carried out during all >fi^d activities using a photoionization detector (PID) and/or a. fiain^ ionization detector (FID). These devices measure volatile org^mic vapors in the air in the parts per million (ppm) range. Ambi^n^ air monitoring using three stationary General Metal Works high volvune air samplers and three Gilian High Flow S^rie^ (HFS) sampling piimps was performed on three separate occas/i

Previous investr ly concentrated their efforts on the geologic and hyd gical aspects of the site omitting the potential migration pat! hat air represents.

The specific objectives of this air investigation were to:

site workers were properly protected;

2-4 o Characterize ambient air quality at and in the vie of the Pine Street Canal Site;

o Evaluate migration pathways for potentially contzuninated ambient air;

Provide ambient air quality data port the characterization of correct health tential future health risks, and the eff potential contaminant migration on nearby environme' eceptors;

Provide data concerning ambient air quality, contaminant migration, and other related parameters to evaluate remedial alternatives for sou^e control and management of migration alternatives .<

Prior to commencing any sit)e ^activities, a field reconnaissance trip was conducted during, tlie week of April 24, 1989. The objective of this preliminary field reconnaissance vas to determine the amount of organic vapors present at the site prior to any surface disruptin ivities in order to facilitate the selection of proper resp rotection for site activities, and to identify any vol a t spots." Two person teams traversed the site v r FIDS. The results of the reconnaissance trip were to verify assximptions in the site Health and Safety Plan.

Continuous real time monitoring by PID and FID was employed during all .fleld^^t«;tivities of the RI to provide personnel safety monitorinjg 9nd 167 preliminary screening of samples. Equipment employed^in^j^ded aN Foxboro Organic Vapor Analyzer (OVA) 128, and an HNu PlitU. with/a Ao.2 eV lamp. Real time monitoring is the

2-5 basis for occupational health and safety protocols while field, however, the equipment cannot be used to contaminants accurately or to detect many of the semivo contaminants suspected of being present at the site. Ambient air monitoring vas used to supplement real time monitoring alloving quantification and detection of all potential contaucinants.

Three rounds of ambient air monitoring for tile and semivolatile analysis vere conducted. Each r' onitoring involved the collection of six samples. Thre les vere analyzed for volatile organic compounds and three es for semivolatile organic compounds. The first round of ambient air monitoring vas performed on July 24, 1989 prior to any ground disroipting activities. This information vas needed to determine the amount of contamination associate jidisturbed surface of the site. This ssiTiipling round va^cdt ior to any veil drilling or soil boring activities thai have penetrated the surface, forming a "vent" for subsurfac* taminants to migrate through to the atmosphere. The second roui of air monitoring vas conducted on October 24, 1989. Drilling vas being conducted in the vicinity of the southemTTJarge slip, a suspected conduit for subsurface contamination. X7rhe\^hird sampling round vas performed December 1, 1989 duririg ^rilding ab^vities in the canal and veil development at varioubslobations throughout the site.

EPA Method TOI, "Meth^d^^r the Determination of Volatile Organic Compounds in Ambient Air Using Tenax Adsorption and Gas Chromatography/Mass Spectrometry (GC/MS)", and Method T013, "The Determinatiwi of'^^enzo (a) pyrene [B(a)p] and Other Polynuclear Aromatic / H^ro^axb^ns (PAHs) in Ambient Air Using Gas ChromatMrapJiy (GC\ and High Performance Liquid Chromatography (HPLC) Analvsi^v" verk used for ambient air monitoring collection.

2-6 These methods can be found in the "Compendium of Methods foyttva. Determination of Toxic organic Compounds in Air," U.S. EPA-?fe007Ar N. 84-041, April 1984.

Method TOI vas performed using Gilian Model HFS air sampling pumps. The air sampling pumps vere calibrated priocô and after each sampling event using a Gilibrator bubble calibra^r. Four to eight liters of air vere collected at a race/of/^0 cubic centimeters per minute. Flov calculation vork ^qteeî^/are found in Appendix F, Pine Street Canal Air Sampling Log Boô \ ^

Method T013 vas performed using General Metal Works (GMW) Model PS-1 Samplers. The PS-1 samplers vere calibrated prior to and after each sampling event usi^g the GMW-40 calibrator. Approximately 325 cubic meters of ai^ver^^&oliected over a period of at least 24 hours. Flov calculationNwo^ shears are found in Appendix F as referenced above. \ /

Volatile samples were collected from tW/aocations. The first location was several hundred yards north of the former coal gasification plant and cond location was northwest of the former coal gasificatio jacent to the filled in southern barge slip. A paralle llected at the second location for all three rounds anic sampling. Semivolatile samples were collected at locations. The first two locations were the same as for the vd e organic sampling and the third location was the northeast comer of the former coal gasification plant. Ambient air monitoring locations are shown in Figure 2-1.

Upwi air monitoring was performed to provide backgro levels. This information was needed to determine f contamination present unrelated to site

2-7 N iBiiiii8888S888l8 /y\ S88S8S8888888SS8S WLBUHwrrweer

AMBtENT AIR MONITORING LOCATIONS FIG. 2-1 PINE STREET CANAL SITE

2-8 activities. Downwind ambient air monitoring vas conduct locate contaminant migration pathvays and quantify prese^ potential future health risks. Meteorological data (vind vind direction, humidity and temperature) vere collected during all air monitoring events to provide information to be used in contaminant migration calculations.

2.4 Surface Water and Sediment Investigation

The folloving paragraphs summarize field ities and methodologies associated vith surface vater diment investigations at the site.

2.4.1 Obj ectives

The objectives of the sediment water sampling program vere to: determine the extent ree of sediment and surface water contamination on-site; ideii' background water and sediment quality conditions in the determine which contaminants, if any, are being deposited into the sediment matrix by surface water and runo^ etermine if contamination is leaving the site via surface wat provide data to evaluate potential risks to human health pnment. Sampling activities were conducted from M 989« Off-shore samples taken from Lake Champlain and from the middle of the canal were collected using a wooden ro

2.4.2 Methodologies

Real nitoring was conducted during all water and sedimen ations using either a Foxboro OVA 128 flame ionizatio ID), an HNu photoionization detector (PID),

2-9 or both. Continuous air sampling was employed before sa: began, during sample retrieval, and during sample prep; (homogenization). Field notes were also taken on all observations during sampling.

Shallow water samples were collected in clean ties obtained from the CLP Sample Bottle Repository, eliminating, possibility of cross-contamination during sample transfer, ntainers were submerged two to four inches below the wat Samples were taken of any floating immiscible layers when"

A Kemmerer bottle was used to collect water samplesât depth in Lake Champlain. Although samples were to be taken in the hypolimnion zone to best characterize the lake's overall water quality, measurements of dissolved/oxygerTêuid water temperature indicated no thermocline. Deep wê^^^^^S^mple^ were therefore collected approximately one foot from tê Hake bottom and from 200 to 300 feet from shore at each locati(m.\^ These are composite samples rather than grab samples due\to boat drift which necessitated filling the Kemmerer bottle several times to obtain the required sample voli

For all surface emperature, conductivity, pH, and dissolved oxygen' in the field using a YSI TLC 3000 Water Quality Mete sher electronic pH -meter, and a YSI 54ABP DO Meter. Water sam' es)^ analyzed for cyanide were field- tested for the presence of oxidizing agents using potassium-iodide starch test paper (Kl-Starch paper), tested for the presence of sulfides using^]>ad acetate test paper, pH adjusted to a pH less than or y^qu^l ~^^o il, and cooled to 4*C. Samples analyzed for volatil/ organics \ene preserved by pH adjustment to a pH of 2 or

2-10 less and cooled to 4*C. Samples analyzed for total metals preserved by pH adjustment to a pH of 2 or less

Surface water and sediment samples were taken from the same locations, whenever possible. In some cases, identical sample locations were impossible to attain due to boat drift or lack of sediments in some water sampling locations. Sediment/samples were collected using a steel shovel or stainless steed >6po^ytrhen the drainage course or water body was dry or shal^qw (l^s^ than six inches deep). A hand auger with a stainless steel Docket was used when the water was deeper. Samples were collected from'^êôp six inches of the substrate in all locations except the canal, where two samples were collected at each sampling location. The first sample at each canal location was collected from the sediment/water surface, the second was collected from apprd^cimêly one to three feet below the sediment surface.

The procedure for collection of canal sediment samples is as follows: one team member stabilized the boat/by rowing, the second team member augured into the substrate to the desired depth. Water depth in the canal varied 10 feet in the middle of the turning basin to six inches at end of the canal. Samples were transferred from the a stainless steel mixing bowl, and brought to shore ion and transfer to specially cleaned bottles obtained e Contract Laboratory Program (CLP) Sample Bottle Repository. es to be analyzed for volatile organics were collected prior to homogenization.

Surgica nitrile gloves were worn by all personnel collectin g samples. All equipment used to collect samples ated prior to and following collection of each samp iiiimize contamination transfer during canal

2-11 sampling, a temporary decontamination line and sample stati set up adjacent to the canal. All decontamination resid unused sample media were containerized in 55-gallon drums the deeper sediment sampling in the canal, difficulties arose in removing coal tar residues from the sampling equipment. Based on previous discussions with the EPA Region I CLP, it was decided to use acetone to remove this residue prior /to routine decontamination. Each piece of equipment detergent, rinsed with potable water, rinsed wi with isopropyl alcohol, and finally rinsed with Acetone was used to remove the tar adhering to equipment only during the canal sediment sampling.

Samples were identified, label packaged and documented according to EPA protocols (EPA CLP) 11^ I protocols were followed for maximum holding times, pr chniques, sample containers, blanks, duplicates, sample fg/custody reports and sample shipping. A total of eight trip and five duplicate samples were collected and shipped with t! sediment and surface water samples. Maximum holding times were not exceeded for any parameter. Analyses wer ormed by laboratories participating in the Contract Labor (CLP). Both sediment and surface water sampl d for complete CLP-Routine Analytical Services ics (volatile, B/N/A and pesticide/PCB) and CLP- ^rganics (23 metals plus cyanide) following EPA protocols (EPA ). In addition, selected sediment samples were analyzed for total organic carbon (TOC) under the CLP- Special Analytical Services.(SAS) program.

2-12 2.4.3 Surface Water Sampling Locations

Surface water sample locations were selected to det quality of surface water entering the site, quality of on-site surface vater, and the quality of surface vater in Lake Champlain. Surface vater samples vere collected from the Pine Street Canal and turning basin, near on-site vater outfalls, in drain^e paths and marshy areas, and from Lake Champlain (Figure 2

A total of 29 surface vater samples vere coil^te^. Tvelve samples were taken on-site. Five vere collected in rov ^ing or marshy areas at the edges of the canal (SW 018, 020), at the area referred to as the "landing pad" in previous reports (SW 017), and in and near the Maltex Pond (SW OQ4, 022). Five more vere collected from on-site ditches and other sltrC^ce depressions (SW 001, 002, 006, 019, 021, 022) and tvovere^llectid from outfalls (SW 003, 005).

Eight samples vere collected in the c^^n^l and turning basin. Seven samples (SW 009, Oil, 012, 013, 014, 015, 016) vere collected before canal sediment sampling activities began. An eighth vater sample (SW 027) vas collected i^om the middle of the turning basin at a later date to determine th^v^^ffect, if any, of sediment sampling activities wvthfes/eai(al wa£er quality.

Nine surface vater sampl^ were collected from Lake Champlain; three were collected along the shoreline (SW 007, 008, 010) north and south of the canal entrance from Lake Champlain. These samples were colleqt'ed'witi^in ten feet of shore in water one to three feet deep. Four Wate^Nsamples, further offshore (SW 023, 024, 025, 026) and wer^ collected\from seven to 13 foot water depths. Samples were also^spll^te^i ak. the lakeshore near the Burlington Water

2-13 SW-SURFACE WATER NOTE: tW-oa LAKE CHAMKAM WATER IffTAKI SW.03* BURUNOTON l>Jg8ID6AVE WATER IMTAia All loCTtbnt ir . ippraJmao

SURFXG E WATER SAMPLING LOCATIONS FIG. 2-2 PINE STREET CANAL SITE

2-14 Company intake (SW 029), and near the Champlain Water Districy pum station intake (SW 028). Both the Burlington and Champlai Districts use Lake Champlain for their raw water supply. 2-1 summarizes surface water sampling locations.

2.4.4 Sediment Sampling Locations

A total of 28 sediment samples were colleq; Samples were collected from the same locatio: samples whenever possible (Table 2-1). No sedime collected from the deep offshore Lake Champlain s sampling locations.

A significemt volume of relatively pure coal tar was anticipated in the canal bottom sedi etter characterize the sediments, both shallow (surfa r samples were collected from the canal. Shallow sampr collected from zero to two feet below the sediment surface; ^r samples were taken from two to six feet beneath the sedimen urface. A total of thirteen sediment samples were taken from the canal and turning basin. Sediment samples talcen. from the canal correspond to surface water samples except: SD-1I>N taken from the turning basin, equates to SW-27; and sample 3U-2L2 was collected from the western side of the canal, while SW-r2sWa¥^Qllected near the eastern bank.

Twelve other samples we^e^olleeted on-site; eleven correspond to surface water samples. No sediment was collected at SW-021. The samples were collected from depressions, drainage ditches, and outfalls. Anad^ltional sample was collected from a low area near the site ^r9:llerN(SD\30).

2-15 TABU 2-1

SURFACE UATER AID SEDItCMT SAMPLE LOCATIONS AND DESOtlPTIQNS

Locatfon/Sample Nuiter Location Dcscrfption

Surface Wjt«p fedfmfflt Low Area Hear Stte Trailer

SW-009 SD-009 NU corner of turning baafn SU-011 SE corner of turning basin SW-012 Canal north, eastern edge SU-013 SO-012S, •012D Canal north, weatcm edge SU-OU SO-OUS, -0140 Canal central SU-015 S0-015S, •01S0 Canal central; anuth of fonaer slip SU-016 SO-016S, •0160 Canal south west SU-027 SO-011S, S0-011D Approximately center of turning basin

Other On-site Locations

SU-001 SO-001 Along natural drainage which etrptiea into canal SW-002 SD-002 At mouth of natural ^^L^nage where it empties into carwl SW-003 SO-003 - Storm/sewer outfall SW-004 SO-004 Maltex Pond SU-005 SD-005 Stom/sewer outfal SU-006 SO-006 Marshy area, headuat SU-017 SO-017 "Landing pad" SU-018 SO-018 Moist area in Phragmite! and allowed to fill SU-019 SO-019 Drainage area in marsh canal SU-020 SO-020 Marshy area east of canal SU-021 Drainage entering NE corner ing basin SU-022 SO-022 North of Maltex Pond SO-30 Low area near site trailer

Lake Champlain

SU-007 SD-007 (south of site 75' south of a storm/sewer outfall) SU-008 SO-008 irallel to canal, south of entrance SU-010 shore ndp^h of canal entrance SU-023 bnal; 6' SU-024 south'^'si/canal; -9.5' SU-025 Offshoi^e from mouth of canal; 8' SU.026 tfshonKporth of canal; 15" SU-028 SD-028 tity water intake, south of canal SU-029 2' offMiprt^near city water intake, south of canal

2-16 N |8l88§l8g|8|§8g8| 88888888888888888 lOLMmfltlMtT 0 II I I I I 1 I I I II I I I I I

SCALE (FEET) 100 200 300 400

LEGEND SD-SEDIMENT

lAMCilOtAVt NOTE: SIVOa LAO CKAMPLAM WATEHMTAia 'SEMOTALONO All

SEDIMENT SAMPLING LOCATIONS FIG. 2-3 PINE STREET CANAL SITE J

2-17 Fewer lake sediment samples were taken than lake surface^ samples, due in part to interference from an extensive a large rock and sheet piling along the shoreline used to prevent erosion. The three sediment samples (SD-7, 8, 28) were collected at the same locations as corresponding surface vater szunples.

2.5 Geological Investigation

Summaries of field activities and methodologies ifnvolved in conducting the soil gas survey and surface and sb}^ur£ace soil investigations are presented in the folloving paragraph

2.5.1 Objectives

The objective of the geolo ation vas to: characterize the vertical and ho tent of soils contamination; characterize the phys erties of the soils, particularly as they relate to fluf ransport; determine geotechnical properties of the soils; and sess the relationship between contamination in the soils and contamination in the ground water.

2.5.2 Soil Gas S es

During the period of a^ine^through 12, 1989 a reconnaissance soil gas survey of volatile or^^^nic compound (VOC) contaminants was conducted to provide' contaminant delineation and placement information fgn^soil borings, and monitoring wells. Ninety-six soil gas samples wg^ciallected over the entire site. In areas where there was a^shal^w >d®pth to groundwater and soil vapor samples could not b^xcollected, saturated soil samples were siibstituted. Thirty-sijc^^tuisated/soil samples were collected, mostly in the

2-18 area around the canal and wetlands at the south end of the The transects of the grid surveyed over the site served as<^ location markers. Throughout most of the site, samples vere collected every 100 to 200 feet, depending on the terrain. Samples vere collected every 50 feet around the area of the former gas plant (Figure 2-4).

Samples vere analyzed for benzene, toluene,/e1^yl/ zene and xylene (BTEX). Occurrences of unidentified compounasy ere noted and tentative identifications vere made vhen possiv3

Sampling locations vere selected from previous investigations, systematic grid transects and initial findings. The soil gas survey vas conducted as a tvo step prcoe^s. In the first step, a large grid (200-foot spacing) vas us^ thcougHdutôst of the site. As the data was processed a tighter gria\ô^ lOOLând then 50 foot spacing vas sampled over areas \ needing more detailed characterization. \ \

Soil gas samples vere collected using a soil vapor probe driven to a depth of threjB'''fe^t. If groundvater vas shallover than three feet, a tvo-foot/sa2dpl>ing-4fP^^ ^^^ used. The probes vere purged of approximately ^ve/(S)~sVortmes of gas using a hand vacuum pump. Gas samples vere^ollected cy attaching a one liter Tedlar bag to the vacuum pump out^t>\Approximately 750 ml of vapor vas collected at each sampling location.

Saturated soil samples vere collected in areas vhere the depths to c^oundwa^r of less than two feet made soil gas sampling impractical/ Sa^rated soil samples were collected using a 24" long, 3/4" iMide diameter soil recovery probe. This probe was driven to its rtil]/2y" depth and twenty milliliters (ml) of soil

2-19 2-20 from the bottom six inches of the recovered core vere transf^rrec to a.forty millilter VOA sampling vial for storage and analysi^

The soil gas probes and the soil recovery probe vere cleaned betveen samples by vashing vith a solution of leiboratory grade detergent and rinsing vith distilled vater. The vacuum piimp vas cleaned by pumping ten to fifteen pump vol of ambient surface air through the pump betveen each sample ar bags used for soil gas sampling vere cleaned betveen y purging three volumes of ambient air and then three volume tra zero air.

Soil gas and saturated soil samples vere analyzed on site vithin three hours of collection usingL.^a Photovac 10S70 portable gas chromatograph. A chromatograph ^as eguippej|vith a capillary column lined vith 100% dimethyl poiysi3,oj^ne,,^7This column is suitable for the analysis of chlorinated yliydrocarbons, light aliphatic hydrocarbons (2 to 8 carbon \;hai.ns) and single ring aromatic hydrocarbons such as benzene, toluene and xylene.

For soil gas analysi instrument vas calibrated vith a gas sample containing aceto dichloromethane (2 ppm), benzene (0.5 ppm), toluene (1 ene (1 ppm), and o-xylene (1 ppm). The standard w injecting specific volumes of headspace over pure duct into a one liter Tedlar bag filled vith ultra zero air.

For saturated soil analysis the instrument vas calibrated against heeidspace^^^yer aqueous solutions containing acetone (.88 ppm), diclilo^methane. (3.98 ppm), benzene (.88 ppm), toluene (.87 ppm), et^ylM^enzene^ (487 ppm), and o-xylene (.88 ppm).

2-21 Soil gas samples vere Injected directly into the instrunentv from, the Tedlzur collecting bag using an automated s^plih^ \^ procedure.

Saturated soil samples vere flooded vith distilled vater to aid in disaggregating the sample and releasing the VOCs. A headspace seunple vas collected using a microboiMB ^yrjjige. All headspace samples vere manually injected/ ytiX.o/ joie gas chromatograph.

The gas chromatograph vas calibrated at the stki^t >^f each day's operation. The instrument vas recalibrated vhenever internal temperatures changed by more than tvo degrees Celsius from the temperature of calibration or vhen^^Fea^carrier gas flov rates changed.

A total of 52 system and samplingNequicTment blanks vere run over the course of the analyses in order \p establish baseline levels and to monitor decontamination proc^ures. Sample blanks collected by draving ambient surface air through the gas probes shoved that decontaminatiSn^rocedures vere reducing levels of contamination to belov ;tf!he''3etection limits of the instrvunent.

One duplica-te i ^ ^olAect^d^ for each fifteen samples. Duplicate soil vapor Bam^>3^sNi(ere collected by filling a second sample bag from a single ps:p)/e installation. Saturated soil duplicates vere collected by driving the soil recovery probe at a second location vithin 12 inches of the original location.

2-22 2.5.3 Surface Soils Methodologies

Surface soils vere collected from July 13 to October 20, This part of the investigation included the collection of systematic, selected and background soil semples. Analyses included full target compound list (TCL) organics amd inorganics and Special Analytical Services (SAS) dioxins and/xurans.

Sampling locations vere selected from the 2 0/foot grid, areas of interest indicated by previous investigati off site locations.

2.5.3.1 Systematic Surface Soils

Twenty-nine systematic surface^ ^s were collected over the site at grid transits (Figure"^ tive debris was cleared and samples were collected fr(^ to six inches belov ground surface. The volatile fraction of^ sample vas placed in a 40 milliliter vial before the remainc of the sample vas homogenized in a stainless steel bowl prior to being transferred to collection bottles. /'The. systematic surface soil sampling routine provided an unbias€d\sainpling of the entire site.

2.5.3.2 Background

Eight background surfac^ssoll samples vere collected from off site locations vithin a one-half mile radius of the site. The background surface soils vere also collected at a depth of one to six inchesy^lov gûnd surface. These samples vere collected to provide sîfficieht information on characteristics of soils not directlj(ass<îate

2-23 2-24 vith on site samples in the Baseline Risk Assessment. JThes^ samples vere collected in the same manner as the systematic/soilb.. \^^ Background surface soil locations are found in Figure 2-6. \^^ \,

2.5.3.3 Selected Soil Samples for Dioxin Screening

Selected surface soil samples vere coll locations and emalyzed for dioxins/furans. Thes collected fron three major areas of concem contamination had been reported on site, the coll six soil samples for dioxin analysis vas only a p screening routine. Vegetative debris vas cleared and the sample vas collected from zero to four inches belov the ground surface. The soil vas placed in a stainless steel^mixing bovl, homogenized, then transferred to collection bottles. ^^TheToc^tions of selected soil samples for dioxin are shown in \ig^inre727Z4^

All surface soil sampling equipment including spoons, augers, shovels, and mixing bowls were thoroughly c3^ned prior to initial sampling. Decontamination of equipment prior to use was performed as follows for all sampl<

o Scmb with o Rinse with o Rinse with o Rinse with distill

All sampling ersonnel wore, clean surgical and/or nitrile gloves when coll handling samples.

2-25 BACKGROUND SURFACE SOIL LOCATIONS FIG. 2-6 PINE STREET CANAL SITE

2-26 ^ N iliii!i§§g§§§§g8§ (J\ 8888S8SS88S8SSS8S wiauM N STicrr I I I I I I I I I I I I I I I I I

SCALE (FEEp 100 800 300 400

LAKE CHAMPLAIN

SAMPLINGXOCATIONuSoZi S FOR DIOXIN SCREENING FIG. 2-7 PINE STREET CANAL SITE

2-27 2.5.3.4 Analytical Methods

All systematic and background surface soil samples^ were analyzed, by a CLP participant, for full Routine Analytical Services (RAS-volatile, semi-volatile, and pesticide/PCB) and RAS inorganic analysis (total metals and cyanide).

Selected soil samples were analyzed by a C ry under special analytical services (SAS), for tetra th"! a dioxins and furans.

Three duplicates, two blanks and two performance evaluation spikes (for dioxin) were shipped to the CLP laboratories with the surface soil samples. During collect^ packaging and shipment, all samples were handled using EPA 1^ holding times, preservation techniques, sample cont^n Le tracking and sample shipping, iniere Region I had d rec[uirements than standard EPA policies. Region I protocol re followed.

2.5.4 Sxibsurface Soil Methodologies

Twenty-three soil and twenty-five monitoring well borings (in ten wel, e drilled during remedial investigation field acstivi re 2-8). Drilling activities began on October 18 and e 2, 1989. Soil samples were collected continuously from e/soil borings and at every five to ten feet from the deepest well boring in any well cluster. Two to three soil samples from each boring were sent to a CLP laboratory for complete orgahlc and inorganic analysis. Locations of the borings werer det^nnihed based on previous investigation results, locatioii^ ors^xistiyigjwells, the soil gas and geophysical surveys and previous saMlino'activities.

2-28 N iiliill§sg§§§§g8§ 88888888888888888 WLBUWN rWEET 0 I I I I i I I I II I I I I I I I SCALE (Fgp

too 200 300 400

• MONITORING WELLS (INSTALLED BY PEER) • BORINGS (INSTALLED BY PEER)

LAKE CHAMPLAIN

0 UWBSAJI

ALLVE ^ INSTALLED ONSITE MONITORING WELL AND BORING LOCATIONS FIG. 2-8 PINE STREET CANAL SITE

2-29 2.5.4.1 Soil Borings

Soil borings were drilled both on land and in the barge Canal borings were completed by the use of a small drilling rig mounted on a 12 foot by 20 foot barge constructed specifically for this purpose. A review of existing data indicated that the majority of coal gasification wastes vere encoiureered vithin 30 feet of the ground surface. Therefore this dec£h>va&/th^ nominal depth set for the termination of the soil boring^ A/geologist vas present at all times during field activities, anoJ^PIDscr FID vas used for screening soil samples. The rig geologist va^sres^onsible for logging the boring, describing the soil cores and determining the depth of termination of the boring. In all cases, except in the area of the former gas plant, the-borings vere drilled through all visible signs of contamination ano'through the complete thickness of the subsurface peat lay\r,\if/t'rese7?t in the boring.

A continuous sampler vas the preferred method of obtaining samples, hovever, problems vith the contitj^ious sampler precluded its use in most borings. These problems vere encountered vhen the sampler cable failed to , preventing the sampling barrel from rotating freely lt_ing in a disturbed sample. The decision vas then m amples by pushing the sample barrel or split spoo ahead of the auger flights. All soil borings were yer their entire depth. This change in sample retrieval method d no effect on analytical sample results.

the canal and turning basin were completed ge. These borings were completed using the h casing being utilized to keep the borehole the canal and turning basin were sampled

2-30 continuously using split spoon samplers. Boring locatic^s shown in Figure 2-9, and boring logs are presented in App^ Boring and sample depths are shovn in TeOole 2-2. Borings on land vere completed employing three drilling rigs. Borings in the canal and turning basin vere completed using a floating barge vith a small drilling rig mountedsôn it. Ten borings (BO 6, 7, 8, 9, 10, 11, 12a, 12b, and 22) vere completed in the vicinity of the former coal gas^f plant and the vetlands vest of it. This area vas knovn" bntaminated from previous boring logs and from anomalies uring the geophysical survey. The ten borings vere placel!k td better delineate, both vertically and areally, the extent of this area. BO 13 vas placed south of the Burlington Electric Department to assess conditions near the southem of drainage area emptying into the vetlands, and BO 14 vas :imately 400 feet further south to establish conditi le St. Johnsbury building. Three borings vere complex the barge canal and turning basin, requiring the use of a .ing barge (BO 15, 16, and 17). BO 5 vas drilled in the f illed^n southem boat slip, vhile BO 20 vas drilled just north of the boat slip to determine if visible contaminatioir'wEich was found during the installation of BO 5 was localized to tH^f^n^r slip. Borings BO 21 and BO 23, located north of the ôal/o^^fieAtion plant, were drilled to further evaluate contamination nbted irt previous boring logs. BO 4 was placed in the Mait^ i»^d. BO 1 was drilled on Ultramar property to evaluate a previ^^ diesel spill and to characterize the northern portion of the site, while borings BO 2 and BO 3 were completed to characterize the northern portion of the site near the turning b^sin (Tkbê 2-3).

2-31 i I I I i I i s § § § § § § § § §

SCALE (FEET) 100 200 300 400 ,.cf^

/3 ^ TUMNOaABN

LAKE CHAMPLAIN ao-11

AH leeOon. wo uppioidnw

BORIN^LOCATIONS (INSTALLED BY PEER) FIG. 2-9 PINE STREET CANAL SITE

2-32 TABLE 2-2 BORING INFORMATION

BORING LOCATION DEPTH (ft) SAMPLE

3-5, 4-5, 9^ , 2-3, 5-7, 24-25 1-5, 5-10, 4-5, 16-18, ll 10-15, 15-20, 25-30 0-2, 10-12, 25-27 8-10, 10-11, 12-13 15-20, 25-30 9-10, 22-24, 27-28 1.8, 19-21 L3 r-18 14-16, 20-22 v8-10, 25 i>, 17-19, 23-25 •15, 17-19, 27-29 0-5, 11-13, 13-15, 15-17, 17 7-12, 15-16, 20 7-8, 16-18, 27-30 7-8, 14-18, 21-30 13-16, 19-20 0-5, 10-15, 25-27.5 5-7, 38-40 5-7, 12-13, 13-14, 27-29 10-12, 15-17, 64-66 4-6, 28-30, 145-147 10-15, 15-20, 30-35 0-2, 10-17, 20-22, 70-90 5-7, 10-12, 15-17, 30-32 3.5-5, 14-16, 40-42 0-2, 10-12 10-12, 19-20, 25-27, 130-132

2-33 TABLE 2-3 SOIL BORING SAMPLING LOCATIONS AND DESCRIPTIONS

Location/Sample Number Location Description

BO-01 North end of site /uel storage area B0'02 North end of site by tjarnlng basin BO-03 North end of sites^y former Pepsi Co. building B0'04 Maltex Pond BO-05 Southern barge slip BO-06 Draina^fe-âjâ, north of gas plant BO-07 Gas pj BO'08 Gas pli B0'09 West of ge^s iânt area BO'lO West of gas plant area BO-11 / V Behind Burlington Electric Dept. B0-12A / /^"^ Isobath of gas plant area j B0-12B

2-34 2.5.4.2 Monitoring Well Borings

Ten well clusters with a total of 25 wells were drilled at Pine Street Site (Figure 2-10). Well locations were placed and well depths selected to take advantage of existing wells. As with the soil borings, a geologist was present at a^/lv^times during drilling operations. A PID or FID was used to breathing zone air and air from the borehole as well to 1 samples collected. Split spoon samplers were used to ci samples at five and ten foot intervals and at any changes. Depths of the borings ranged from eight feet to t. The installation of wells in these borings is described in Section 2.6.1.

Borings for wells were made u ow stem auger and mud rotary techniques depending oi^ and lithologic conditions.

Well cluster MW-01, just outside the )s£ fenceline and east of GE, and cluster MW-02, located on GE properi:y, were placed to determine the extent of o^ntaiainant migration downgradient from the old coal gasification

Well clusters MVK03 lind MW-W were placed near the old coal gasification plant itsePl. AS stated previously, this area was known to be contaminated bak^^on past boring logs and anomolies encountered during the geophysical survey. MW-03 was placed just north of where the old goal, gasification plant was located, next to an inteTmittentvdrainage ditch, while MW-04 is west of the old coal gasaficatiohvprant. Because this was such an important area, the de^est-sboring) ai MW-04 (176 feet) was continuously sampled.

2-35 N i i I i I i I § 2 I s § I 8 g § § S888SS8888S888S8S WlBURNSTWEgT 0 •3'»00 -2440 SCALE (FEET) •1-fOO 100 200 300 400 04<»

1440

IIW-1SA3 >-MK> ^ CD °d3' 94-00 4-M)0 LAKE CHAMPLAIN S-MO

•440

7-KIO

8-t-OO

••fOO

10-t-OO B^AHPgTHEFr 114-00

12-fOO

134-00

14-fOO

le-KX)

17-fOO

IB-fOO

1S-«-00

20-t-OO

21-fOO

22-»^00

23-t-OO

24.f00 LOCUST STBfcET 2S-i-00

26•^00

27-fOO

2a-f00 ST. JOHNSBURY TBUOONO 2»<«-00 ao-foo

314-00 I tOCMDOns M BPPfQOTMto 0 lfWDSA.S

MONITORINGKWELL LOCATIONS (INSTALLED BY PEER) FIG. 2-10 PINE STREET CANAL SITE

2-36 Well cluster MW-05 is located offsite, 500 feet south site. This well was drilled to provide background Cluster MW-07 was placed near the Maltex building and the Maltex Pond area (the site of a past removal action), in an effort to locate any possible contamination remaining after the Maltex Pond cleanup, and to determine if coal gasification was£^ are present to the north of the old coal gasification plant ^r^, Mid east of the canal.

Well clusters MW-08 and MW-09 were installed^ td\^stablish conditions at the northern and western edges of the "^4;^r while clusters MW-10 and MW-ii were installed to characterize the filled- in northern barge slip (MW-11). Table 2-4 provides well locations and descriptions.

A decontamination pad was cons ore any drilling began. All drill rigs and drilling e were steam cleaned upon arrival at the site and between ee^ oring. All sampling equipment was steam cleaned between each îng and washed with a detergent rinse and a distilled water rinse between each sample. All water from the decoâmihation pad was collected and drummed and all drill cutting^w;ê\containerized and moved to a central storage area.

2.6 Ground Water Investi

Field activities and methodologies used for installation of the monitorjjig-jwells and procedures used during the ground water investigatlon-^re^iscussed below.

2-37 TABLE 2-4

MONITORING WELL SAMPLE LOCATIONS AND DESCRIPTIONS

Location/Sample Number Location Description

MWOl East of GE property two MW02 Northern GE property two we] MW03 Gas plant site, four wells MW04 Gas plant site, two wells MW05 Off site sotitti^of Lakeside Avenue, tvo veils MW07 Behind Mali four veils MW08 Blodgett proi est edge on site. one veil MW09 West of turning laisin, four veils MWIO North end of site, tvo veils MWll 'ByN^outhem barge slip, four veils

2-38 2.6.1 Objectives and Methodologies

The objective of the ground vater investigation vas to identify the occurrence, distribution and migration of contaminants in the ground vater and, in conjunction vith the subsurface soil investigation, determine the contamination pathvays ahd receptors.

Tventy five veils vere drilled, ranging fn a^tti/rrom eight to 192 feet. These veils vere installed in Ibs^lu^ers, for a total drilling depth of 1260 feet. Well locationk\ar^N^hovn in Figure 2-10, and veil logs are presented in AppendiWc. Well depths and screening intervals are included in Table 2-5, and a visual comparison of veil depths, screened intervals, and sample intervals is included in Appendix yGr"~""~Allyel Is vere installed utilizing auger and/or rotary mud («sllXingj A~t:embination of the tvo was occasionally utilized, with\th^^/inf^ial borehole being augered to accommodate eight inch outeryca^ng. These wells were then completed using rotary mud drilling\ y

Each well consisted of^ a two inch diameter PVC riser, with a two inch diameter slot; 10) PVC screen at the bottom. In addition, sediment tr; ailed in the bottom when deemed necessary. Screens by 20# sand, generally to two feet above the screen^ the sandpack a two to three foot bentonite seal was establ

Wells were backfilled with grout above the bentonite seal, and capped wit ent surface.seal. Protective steel surface casing with locldib, overs were installed on all wells. Wells which penetr ^na\ted strata were cased with eight inch steel casing ace through the contaminated interval; some wells requi ^scoping design utilizing six inch steel casing

2-39 TABLE 2-5 MONITORING WELL INFORMATION

SCREENED INTERVAL DEPTH TOP BOTTOM WELL # (feet) (feet) (feet) reened Lithology

MW I A 11.0 MW I B 51.0 Silt/Clay MW 2 A 14.5 Peat MW 2 B 33.0 ilt/Clay MW 3 A 12.0 Peat^ MW 3 B 39.0 Lower Silt/Clay MW 3 C 67.0 Lower Silt/Clay, Till MW 4 A 37.0 Lower Silt/Clay MW 4 B 167.0 Till MW 5 A 15.0 Fill MW 5 B 35.0 Lower Silt/Clay MW 7 A 9.0 Fill MW 7 B 15.0 Peat MW 7 C 24.5 Sand MW 7 D 92.0 Lower Silt/Clay

MW 8 A 150.0 150.0 Bedrock MW 9 A 15.0 14.5 Fill MW 9 B 35.0 -28.0 Sand (Gravel) MW 9 C 192.0 192.0 Bedrock MW lO A 15.0 14.0 Fill, Peat MW lO B 25.0 24.0 Lower SiIt/Clay MW ll A 6.0 10.0 Fill MW II B 10.0 20.0 Peat MW lie 30.0 35.0 Lower Silt/Clay MW II D 118.0 128.0 Lower Silt/Clay

2-40 telescoped inside of eight inch casing to prevent contamination of multiple intervals.

All existing wells on the site were redeveloped in an effort to utilize existing data and to minimize the number of wells installed during RI field activities. Redeve^/0]^ment was by blocksurging with a two inch diameter stainle teel bailer. Wells were then purged until three equivalent/wi es were removed or the well went dry. This technique Pfetf: ^rmed on the 15 existing monitoring wells (in ten clusters) o th^N!*B" series (installed by Jordan, 1982), the seven wells of th series (installed by Emhart, 1981), and the five wells on Ultreunar property (designated "UM" and installed by ERM-Northeast, 1986). It was successful on all wells exceptr-.B^^B, which was found to be silted up to the water table (except durin^-~*lie winter, when the water table had risen above the level o^^^ltXz/ B-111 was found to have been destroyed. Locations of all existing monitoring wells on the site are included in Figure 2-ll\ \

Groundwater samples were collected from the 25 wells installed during the investigation from the 26 existing wells which were deemed suitable after ent. Groundwater samples were also collected from the wells on Blodgett property. Existing wells which elude: Wl, W2, W3, W4, W5, W6, W7, BIOIA and B, B102B, and B, B104A and B, B105, B106A, B107A, BIOS and B108A, B109 e five wells on Ultramar property. and three existing wells on Blodgett property.

yere recorded in all sampled wells on February he exception of MW4A, MW9B, MWllB, B104A, and The latter well water levels were recorded

2-41 N |S|!ili|2ISSI88SI S8SSS8SS88SS8SS88 I I I I I I I I I I I I I

SCALE (FEET) 100 200 300 400

• MONITORING WELLS (INSTALLED BY PEER) • BORINGS (INSTALLED BY PEER)

^ PREVIOUS INVESTIGATION WELLS

lAKE CHAMPLAIN

All knjtlui'n t n .pprodniMi

ALL O^^TE MONITORING WELL LOCATIONS AND PEER INSTALLED BORINGS FIG. 2-11 PINE STREET CANAL SITE

2-42 on March 21, 1990, although they are of only limited us( fluctuations in the water table. This information was determine potentiometric surfaces and hydraulic gradients for aquifers present at the site.

Rising head slug tests were performed on 12^ Is installed during RI field activities in order to characte, ydraulic conductivities of the different aquifers at th< hese tests were performed by withdrawing one liter of water e well and monitoring the resulting rise in water level usii^ an> In-situ pressure transducer and data logger.

2.7. Ecological Investigations

Ecological investigations were characterize the site and assess the type and extent ands; identify flora and fauna potentially affected by actua" potential contaminant ll release including threatened or endan^ ed species; and to determine contaminant concentrations in biota.

2.7.1 Wetlands Deli

A wetlands delin^troji w^s cbjj^cted following the methodology detailed in the Joint EPA-ArBiy Corps of Engineers "Federal Manual for Identifying and Delin^atinfcr Jurisdictional Wetlands." This methodology requires an assessment of wetlands hydrology, hydric soils, and hydrophytic vegetation. Soils identification was difficult b^cau&Bvthe site is composed mainly of fill material and is so cla«sj:fi^d^by\the Soil Conservation Service (Allen, 1974).

A ransect at approximately the centerline of the site and st-west transects were run. Data sheets were

2-43 completed at over seventy locations east of the Canal, species and percent cover were recorded. The wetland iii category was noted for each species based on the U.S. Fish and Wildlife Service Plant list for the Northeast (Reed, 1988).

After data analysis, each location was plac one of four categories: wetlands, probeQjle wetlands, pro^ and, and upland. A map tentatively delineating the w 'undary was then created.

2.7.2 Ecological Populations

During site characterization, ^pecial effort was made to locate two species of concern reportedly^-^-at the site (Vermont Natural Heritage Program). Comparison o^^"Sljte f eaStures with aerial photographs was accomplished by systematically walking the site. Diseased or dead trees and shrubs were notec^and vegetative species composition changes recorded to focus th^^i/etland investigation. Mammals, avifauna and heptofauna were noted (as well as indications such as burrows, nests, etsO during the survey and by all field personnel throughout the course of the remedial investigation.

2.7.3 Biota Sam'

Macroinvertabrate sam]^ies >rere taken in the same locations as sediment samples to correlate data. Twenty-one samples were collected on-site; one was collected at site 28, in Lake Champlain south of -^^ile'^^te; and a background sample was taken at the La Platte Rivea^'^SrshX Figure 2-12 shows macroinvertebrate sampling locations.CDissolyefl oxygen, temperature and pH were recorded at each sair^le Ibqation/ After collection, samples were preserved in alcohol and stained/with Phloxine B. For more sampling information

2-44 N rr\ 888S8S888888888S8 WLSUWtTWgr

SCALE (FEET) 100 200 300 400

LAKE CHAMPLAIN

ilOTA SAMPLE LOCATIONS FIG 2-12 PINE STREET CANAL SITE

2-45 see the Biological Technical Memo, September 1989. Samp taken to assess species numbers and composition on-site potential future sampling efforts.

Fish were sampled to provide data for both environmental and human health risk assessments. Target species one species each of generalized feeder, insectivore, and ton e trophic levels. Fish were sampled by gillnetting<^u 125-foot monofilament experimental gill net with 1-, 2-, nch stretch mesh panels. Three overnight sets were made May t three locations: mid-canal, canal entrance, and the control^rea, the La Platte River marsh.

All fish captured were weighe and inspected for signs of gross external pathology. anima)Es were released. A proportion of dead animals was for tissue analysis through CLP SAS for VOC, semi-volati pesticides/PCBs, and inorganics. For each species, a whole bo d fillet samples were analyzed.

2-46 3.0 PHYSICAL CHARACTERISTICS OF PINE STREET CANAL 81

This section describes the physical characteristics of the Pine Street Canal Site as determined by the activities described in the previous section. Surface Features. Surface features, climatology, surface water hydrology, geology, l^d/ogeology and ecology will all be discussed in this section.

3.1 Surface Features

The Pine Street Canal Site (Figure 3-1) encompasses^80 acres on the eastern shore of Lake Champlain, which delineates the site's western boundary.

The canal and turning basin are inctive features of the site. The turning basin measu: mately 300 by 300 feet and connects to Lake Champlain th: a narrow inlet under a railroad bridge. Average water depth e turning basin is 11 feet. The canal runs to the south from e turning basin. The canal is approximately 8^ eet wide although in some places the artificial banks are no in place and the canal merges with swampy areas. The can ^ately 1100 feet long with water depths ranging from urning basin to six inches at its southern end. Th hern end Of the canal turns into a wetlands and is directly w^ the former coal gasification plant location. Two filled-in bargVslips are located on the site, one to the north of the turning basin and one close to the southern end of the cana^t—Water elevation in the canal averages 96.5 feet MSL during tl

The emnants of the bulkheads and artificial banks of the cana he turning basin and northern end of the canal but little evi of the artificial nature of the canal remains

3-1 PINE STREET CANAL SITE SITE MAP FIG. 3-1 in the central and southem portion. In the central portj water depths decrease, the canal is becoming choked with d^ and flotsam. The progressive decrease in depth to the southem end of the canal is due to a corresponding increase in canal bottom sediments. The canal bottom sediments are fi grained and uncohesive. In the turning basin, their thic is from six inches to two feet and they overlay a more coh rse sand, pebble and clay base. At the juncture of ti(e and turning basin, sediment thicknesses vary from two to fo and at the southem end of the canal, uncohesive sediment averages ten feet. In the canal the sediments overlay a more cdKesive clay layer. The southern end of the canal gradates into a vegetation- choked wetland. The wetland/canal is contained on the west by a Vermont Railroad embankment that south between Lake w Champlain and the canal. The heigh kment is 104 feet ll> MSL or about eight feet above canal level. The southwest I portion of the wetlands is contained northern end of GE property which is at 100 feet MSL. wetlands area extends southward, between GE and the Burlington Electric Department and [ St. Johnsbury Trucking C ny (both located on Pine Street). This southem end of the ects surface runoff, cooling-water L (GE) and storm wate^ The Burlington Electric Company property and a berm' er gas plant (built in the late 1960's) contain the we in the eastem central portion of the site. Lakeside Avenue, forms the southem boundary of the site, has three businesses on^'the north (site) side: St. Johnsbury Trxicking occupies the southeast comer of the site; the General Electric occupies approximately 12 acres in the south- I center oi tlw the Blodgett Company occupies a triangle-shaped 12 acr^s 4f J een the Vermont Railroad embankment, Lakeside Avenue ai^d E plain. The average elevation at.this end of the site is\ MSL.

3-3 The former coal gasification plant was located just Street in the middle portion of the site. The Burlington< Department (BED) is to the south, the wetlands to the west and an^ E-W drainage ditch and open fields to the north. The BED, Pine Street, the E-W drainage ditch and the beinn containing the wetlands form the nominal boundaries of the coal gasificati«m plant area. This area is approximately 4.5 acres with an av^rasfe elevation of 104 feet MSL.

\ To the north of the former gas plant, occupyj^g xjie central portion of the site between Pine Street and the cam^^are open fields, the former southern barge slip and Maltex Pond. Trees line the drainage ditch, canal and Maltex Pond. The 300 square foot pond was once connected to the cana now has a berm separating 0 it from the canal. The northern site is occupied by businesses: The Maltex Buildirt Maltex Pond), an i office building; a former Pepsi Bottlirti any building; Citizens Oil Company; the former Ultra Mar Petrol torage facility, which is directly north of the turning basin d contains• the former northern barge slip; and the Burlington Street Department whose property forms the nort)r^rrr^oundary of the site.

3.2 Climatology

The following is a. discussion of climatological factors affecting the Pine Street Can^Site. Data on temperature, winds, precipitation and local' weather patterns are included.

Ampl 1, moderately warm summers, and fairly cold winters ^eristic of Burlington, VT. The climate is predominan ental. A moderating influence is Lake Champlain^ e >0f the north-south orientation of the Champlain Valley, winds are in these directions. They tend to

3-4 blow from the south in summer, but in winter north winds a; winds are about equal in frequency.• Topography is onl] influence on climate in the western part of Chittenden County, where elevations are mostly less than 500 feet above sea level. The influence of Lake Champlain is readily shown by the presence of the shore fruit belt. Inland highlands are mosre^restricted to hay, pasture, and forests. Small-scale topogra atures and even kinds of soil also affect climate nea und. For example, low spots into which cold air drain^ calm clear nights are frost prone. A soil having a higli ic-matter content, such as muck and peat, is a poor conductor of red heat. The surface layer of muck and peat therefore may cool much more during a calm clear night than that of a sandy soil in a comparable C location. A small weather station was installed oiST-the site to measure 1 temperature, wind speed and direction, barometric pressure and relative humidity, especially during \irS sampling events. A weather seirvice observation station is^located at' Burlington [ Airport, where climatological data (Tsible 3-1 and Tables 3-3 through 3-7) are recor t are representative of much of the t westem part of the/c Iso, at the Huntington Center, climatological da ) are recorded that are [ representative of a in the rougher foothills area of the eastern part of the court' or every 1000 feet of increase in i; elevation, climate in the tem highlands average 3® to 4® F. cooler than in the western part of the county.

3.2.1

:h, July, averages about 70** F, The number of days when""^e "tijfmnirature is 90° or higher averages ten or less throughout th^\C9unty in most summers, but may vary from none to

3-5 TABLE 3-1 TEMPERATURE AND PRECIPITATION, BURLINGTON, VT^

[ElevUleix, 333 feet; data for tha period liMi to IMT] / I Temperature / yfteemlUttiti

Two yeanfax 10 One year BvlO ATerage daDr— wiU hsTe At lesst 4 willhaTo-iv ' ( Bays with— dAys with— ^ S. ^ \ Mo&tb A^ersR "s. Arersre mobtUy Mvdmum Minimum monthly snow^s / Predpi. tempera t«mpers- total faU Snow> Snow Ution Muzimum Mini™v"i' Mesa ture equsl tnre equal Less More falll eoTer 0.10 to or to or th.n than— inch or 1 inch ineli lower lower mors or more or more • t««TV th»n— ^^_ / ^.....^^ •/. •/. HAa ^Mbt^>%. HAa '»**• January.... •r25L. 4 4 9 18*r.. 2 *r. 43 -11 ""^* 17.8 5 26 Februarr 27.1 17.4 42 -13 \\L7^1 i^ ..^as 17.7 5 23 MsTch,.. 3&3 17.7.e0 28.7 58 0 NSLllS ^-;a9 ~-^F2 s 1L3 3 17 &Z4 sao 41.3 70 21 V63 . /^Y 3.8 2.1 1 1 ^.:::::: 6&4 413 53L8 82 30 zN» V vF*s 4.8 a2 P> « 1 Juna...... T7.1 5L2 »4.2 89 42 /|.6 5.4 0 w*0 0 July 8L9 5&0 92 46 ai3.85i S ^ 0 0 0 0 Ancust . . 79.6 53.8 ea68.o7 92 46 3.37 SiaoS 0 0 0 September.. 7a 6 4&1 58.4 88 35 3.31 \\/ S 5 s 4.9 0 0 October 5&S 3«.« 47.6 75 27 Z97 » L 4 4.6 'i. ^ • ^ ^ [ MoTember.. 4X4 27.1 3&3 60 17 Z62 L3 4.4 5.6 2 4 December... 3a2 IZS 2L5 50 -9 Z13 3.9 1SL8 4 19 Yaat 54.1 3Z2 43.2 «-20 33.21 2&as2 39.3 7a 6 20 90 80 ^ ^ is i Leas than 0.5 inch a day. c »Trv». * ATer&ge annual highest miximnm. [ * Average '"""^J lowest miTiininm [ L

Source: Soil Su^v^y ^t Chittenden County, VT, USDA Soil Conservation Service Jan. '89.

3-6 TABLE 3-2 PRECIPITATION, HUNTINGTON CENTER, VT^ r IJ

[ I I

^ Source: USDA, Jan^^89

3-7 TABLE 3-3 FREQUENCIES OF SELECTED TEMPERATURE, ETC. BURLINGTON/^^^

c i [ t I [ 1

1 \/ Source: USDA, Jan. '89

3-8 TABLE 3-4 PROBABILITIES OF FREEZING, ETC., BURLINGTON,

r Dates for (iTes probability and^tMi, Probability 32* F. or lower 28* F. or lower 24* F. or lower 20* F. or lower 16* F. or lower

Spring: 1 year in 10 later than... May 23 May 13 April 14 April 8 2 years in 10 later than.. May 19 May 8 April 9 AprU3 5 years in 10 later than.. May 11 April ~ March 29 March 24 8 yean in 10 later than.. May 3 April March 18 March 14 Fan: 1 year in 10 earlier than. September 19 October November 1 November 10 2 years in 10 earlier than September 23 October 5 Norember 6 N'orember 15 i 5 years in 10 earlier than September 30 October 13 Norember 16 November 25 8 years in 10 earlier than October 7 October 21 NoTember 26 December 5 [ E C [ I

Source: USDA, JanX/89

3-9 TABLE 3-5 AVERAGE FREQUENCY OF POSSIBLE DRYING, ETC., BURLINGTO

r Number of possible runs of specified length > Rxm V\ ^ / length I (days) January February March April May June July August October Novem Decem Annual L tember ber ber 2 12 4 lao 1L5 ILO lao lai ia8 lao 12 0 10 4 IZl isas 3 7.6 a3 7.3 a7 ao ai •~-^* ai 7.5 a4 7.4 8a2 4 5.4 4.3 4.9 4.4 3.9 4.0 (/oi *•^! 4.0 5.0 4.2 5.1 5316 I 5 4. 1 3.2 3.5 3.1 Z7 Z8 \ 2^«^ ^3.0 --4J 3.7 ai 3.8 38.8 6-7 3.2 Z4 Z7 Z6 3L1 2.1 \?^2\ ^^2 M Z8 Z4 Z9 29.7 8-10 1.9 L 4 1.8 L4 12 1.1 --J/2 1.5 L3 1.6 ia8 11-15 Ll a9 a9 a9 ao a3 ^ ^ A-^ ao a8 a7 09 8.8 16-20 a8 as a4 a2 a2 ai <>-k va/0/ 2 a2 a3 ai 04 3.1 I 21-25 a3 a2 a2 ai ao3 aoTy ( ai ai ai az 14 28-30 ai a 1 ai ao3 ao3 K \ ao3 ao3 ai a2 as 31-35 ao3 ao3 ao3 ao3 \ > ao3 ao3 ai as 38-40 ao3 ao3 \ / ao7 41-45 ao3 ao3 V , ao7 c 45+ ao3 ao3 ao7 > From daU for 29 years, 1937-1906. [ [ [

^ Source: USDA, Jan. '89

3-10 TABLE 3-6 AVERAGE FREQUENCY OF DRYING, ETC., BURLINGTON, VT

r , Number of discrete runs of specified length Run ^\y length (days) January February March April May June July August Sep. October Novem Decem AnnpiJ temoer ber ber

2 as as as 07 as 05 /TtT- -,.07 ao a4 04 a4 ai 3 a4 04 a5 ao 06 05 / 06 06 a4 05 as ao 4 ai 02 as 04 04 05 \ •'^'f- _ 05 ^-M. a4 03 as 4.3 6 a4 04 02 OS 02 04 \*>LT ^ * ay OS OS a3 4.0 8-7 05 a4 04 a4 OS a7 \a«^ V A5, -~~X4 a7 05 as &9 8-10 as 02 as as as 06 ^s its a4 05 as &4 11-15 05 a4 05 02 0^3 \Ar a4 05 a4 &0 16-20 a2s ai ai aoi ai 01 aK 9/* 01 a2 a0 s 02 1.4 21-25 ai ai a2 ai 0 0 01 V 5S12 ai Ol Ol 28-30 ai ai 0 0 0 0 00oo3s 003 ai as 28-40 0 0 0 0 0 0ao s 0 \ o\ 0 0oo s 0 0 0a z 41-45 0 0 0 0 0 0 0 \?/ 0 0 .> 0 0 0 48+ ao3 0 aos 0 0 0 0 V0 0 0 0 0 ao7 I rn m daU for 29 years, 1937-1960.

^ Source: USDA, Jan. '89

3-11 TABLE 3-7 WEATHER RECORD, BURLINGTON, VT^

I E C

' la Langieya, or pam-calories per square centimeter. * Letm than 0.5 da>. I 'Trace.

c for BwitJigton, Vamtmt

Source:

3-12 as many as 20 to 30. Nights are almost always cool, eve; warmest summers. Tcible 3-1 contains extreme temperatures to occur with the stated probability. These temperatures, which should occur at least four times a month in at least two years in 10, generally are near the average monthly extreme. They may be used as a rough estimate of the extremes to be expeobed each month for any year. Table 3-3 shows the average freguejrcy y6f:^ specified temperatures by month.

Table 3-4 shows the probability of freezing tei^>^atiu:es after r specified dates in spring and before specified dates ii^vfall. For example, at Burlington, there is 1 chance in 10 that the E temperature will drop to 32° or lower after May 23. The 50-50 chance day is May 11. A 32° freez seriously damaging E to very sensitive plants, but har withstand even lower temperatures. The average date^ t freeze in spring E varies from early in May along the Champlain shore to the middle of May over much of the county and the end of May at some of the highest elevations. The average date of the first freeze E in fall varies from the middle of September in the extreme eastem highlands to after Octc^er X\ along Lake Champlain. The average length of the freeze-free seWsonHs about 150 days along the shore.

E 3.2.2 Precipitatia

In the western half of the county, annual rainfall generally is about 32 to 35 inches except at the higher elevations, where it .5 50 inches or more on the highest ridges. There L seasons, but precipitation during the summer ercent greater than during the winter. There short but fairly common dry spells in summer. ells there always is an adequate supply of

3-13 irrigation water because the seasonal total precipitation is as compared with the rest of the nation.

Snowfall varies considerably from one winter to another. It may also vary greatly from place to place in the same season. The average seasonal snowfall is between 60 and 80 in most of the county but is as much as 100 inches at som the highest elevations. A continuous snow cover, one inch d occurs for at least a month practically every winter. inters the snow cover may not last this long at the lower ions. At E Burlington the average duration is 61 days, starting ecember 28 and ending by Febiniary 26; the extremes range from 16 to 134 days.

E At Burlington the average sea depth of snow is 15 inches. The date of the maxim snow usually is E February 8. E In most of Chittenden County, the miplmum depth of snow is about six to twelve inches, whereas the maximum depth is from two E to four feet. For Burlington, currence of snowfall in 1 day E is as follows:

Amount in Inches Frequency in davs per season E Average Extremes 20 11 to 31 I 11 5 to 20 4 0 to 8 1 0 to 3 0.4 0 to 2

Tabl 3-2 contain additional snowfall data.

3-14 3.2.3 Dry or Drought Periods

Frequencies were calculated from the Burlington daily r

Table 3-5 gives the average monthly and annual number of droughty runs of specified length. Any day that had/^less than 0.15 inch precipitation was counted as dry, with one excejition. If any day had 0.05 inches or more, and the next/ day/h^ enough precipitation to make a total of 0.20 inch or<ôrfesAor two days, both days were counted as wet days. All rvins ofN^ô^^nsecutive E days or more were tabulated. If a run ended in anoth^ônth, it was assigned to the month in which the larger part of tne period occurred.

A long run also may be consid ain several shorter runs. For example, a 12-day run corf ect, three four- I day runs or four three-day runs, reason, the average number of all possible runs of various len were also computed and are listed in Table 3-6. Because the do not appear to vary E much from one place to another, they may be used as estimates for E any part of the county. Table 3-7 conta ata available for Burlington. E They are based upon brd or more, except for data on solar radiation, which rages for a period of only 3 years.

3.2.4 Storms

L Thunderstorms occur on an average of 20 to 30 days a year, though tne/num^fer varies considerably. Most of these storms do littlesdamage; instead, they bring beneficial rain. But heavy rains thatsaccsmuanVthe more severe storms cause soil'erosion and injure plant^>.- Spring and summer storms are accompanied by hail

3-15 about once or twice a year at a given location, but the hail^ seldom are numerous enough to cause extensive crop or p^ damage. Some local damage may be severe. Hurricanes Chittenden County only about once in 20 years. Strong winds and heavy rains from coastal storms, or "northeasters," are more frequent. They usually do not cause serious damage, hovever, because Chittenden County is located far inland ^nd/is sheltered by the Green Mountains. Tornadoes have struck in n County but are not common, and they usually affect ^ 1 all area. Personal injuries and significant property damage , yet the E danger should not be minimized.

3.3 Surface Water Hydrology

The Pine Street Canal Site e both developed and undeveloped property and for the m^ haracterized by D poorly developed drainage (Figure he barge canal and turning basin are the major collectors surface vater runoff. C The highest part of the site runs along Pi treet at an elevation of 108 feet MSL. The lowest part of the site is the canal. Average water elevation ^e canal during the summer is 97 feet, C Water level changes in nplain are reflected in water level changes in the canal, directly connected. Flooding E is common at the sit iring the spring thaw. This is caused by the rise in wa stye Is from Lake Champlain and not from E the collection of surface from the site into the canal. The record high water mark for the site is 101.8 feet MSL, at which E time a large portion of the site is under water. The Vermont Railroad e;ii6an}mfei^ that runs north and south at the western edge of the site/is""^Ntopographic high at 104 feet MSL. The embankment forms 2/wat^shed,\with surface water on the western side draining into LakeN^a^plain atnd surface water on the eastern side draining into the camti.; The topography at the southem end of the site is

3-16 mrnmm^ mmm

PINE STREET CANAL SITE SURFACE WATER HYDROLOGY FIGURE 3-2

f^r

N/SEWEH ILLS OXqEOUTFAUS relatively flat because of the development of businesses a Lakeside Avenue. However, GE discharges non-contact cooling into' a drainage area on the east side of their plant. T also a storm/sewer outfall and drainage ditch in this area. This area forms the southern most area that collects surface water and channels it northward towards the southem end of the canal and the wetlands. There is another storm/sewer outfall al comer of the vetlands. GE also discharges water from the northwest corner of their property. Tl well developed drainage ditches that run east^ surface runoff toward the canal. One, located ji former coal gasification plant, empties into the other one, further north, directs surface water toward the Maltex Pond area. Two other poorly developed east-west drainage ditches channel runoff into the turning basi

3.4 Geology

3.4.1 Soils

The soils of n have been classified by the United States Departm^ Agriculture in cooperation with the Vermont Agricultural "Expe station and the Vermont Department of Forest and Parks.

Soil spient classify soil profiles, which are natural layers oi in a soil extending from surface to parent materia] eries and soil phases. A soil series is made up of s^ similar profiles. With the exception of a different the surface layer, the soils of a series all

3-18 have similar thickness and arrangements in the major horizons, series are named for a town or geographic feature near the where it was first identified. The soil series are further into soil associations. A soil association is a landscape that has a distinctive proportional pattem of soils. It is usually made up of one or more major soils and at least one minor soil.

In Chittenden County, where Burlington is fifteen soil associations have been identified. These f ciations have been grouped into three types of landscapes:

(1) Soils forming in water-deposited materiai>Vin the Champlain Valley. Water-deposited materials range from sand to clay in texture.

(2) Soils that form in glacial amplain Valley, and

(3) Soils that form in the Green >fbun^ains and associated foothills. These soils are found on the main range and the foothills o^f-^he Green Mountains, located in the eastern part of the\ounty.

The Pine Street ng within the water-deposited soils. The nine soil iations that have formed in this environment are:

Vergennes-Covington Association jn Association lately-Vergennes Association lam-Scantic Association Lgrade-Munson Association ludley-Winooski Association

3-19 (7) Muck & Peat Association (8) Adam-Windsor Association (9) Colton-Stetson Association

The associations that cover the Pine Street Canal site are mainly the Adam-Windsor and the Enosburg-Whately-Vergennes Associations. The Adam-Windsor Association are/6o2ls that are level to steep, excessively drained, sandy soil tas, old lake beaches, and terrace locations. Most of t re formed in deep sandy materials that were deposited by va^ an.extinct lake. In certain places, the sandy material is n vith loamy or clayey lacustrine deposits at depths less th^ 5 feet. The Enosburg-Whately-Vergennes Association are level to steep, moderately veil drained and poorly drained sandy, loamy, and clayey soils, on old beaches of lake plains. MSrterlal consists of sand deposits that are underlain vith loa^ ^^te^ial^ depths of less than 40 inches.

3.4.2 Regional Geology

Burlington lies i Champlain Lovland physiographic province (Figure 3-3), dominated by the Lake Champlain drainage basin. Loca ^ m of the broad valley betveen the Adirondacks of N reen Mountains of Vermont, the Champlain Lovland is r cent of a lake plain, although it consists of irregular top y. Rocks forming hills and lov mountains tend to be erosional remnants of former ridges which were dislocated by compressive stresses and pushed westward along low angle frac^ttire~">cmes, resulting in an eastward dip to the rock (Stewartyi9^3y>v. cWjlogic maps of Vermont and the Burlington area are shown In Figures\3-4 and 3-5.

3-20 FINEST CANAL

SHOWING FVIYSOGRAPHC SUBOtVlSJONS VERMONT

PHYSIOGRAPHIC PROVINCES FIG. 3-3 PINE STREET CANAL SITE

3-21 VE.PMONT GEOLOGICAL SURVEY Charles G. Doll, State Geologist

Thr morf deuiird C«nt*nnial CMlogic Map of Vcrmoni, arde ] 254000, ivgilablr from Scai« Librarian, Vermont SMI « Ubrary, Montpclwr, Vermont 0^602. Wrilc tor |iublic*iion liat.

IZED GEOLOGIC MAP OF VERMONT •

•OLOGIC MAP OF VERMONT FIG. 3-4 PINE STREET CANAL SITE of tie KineibLrg lyndinorkxTt, Wegt

3-23 There are several prominent north-south trending thrust f «mil in the area, similar to thrusting seen elsewhere in the Appalachian chain. The Champlain thrust is a major fault in thi^\ôup^ extending from the Canadian border south to Snake Mountain. This fault passes just west of Burlington, near the mouth of Shelburne Bay. In the vicinity of Burlington, the thrust sheet has a base of Monkton quartzite, and overlies a footwall of/Trenton Group shale. This fault was active during the Taconic oro^ny^f middle to late Ordovician time (Stanley, 1980). The Clâmplain lowland is also cut by numerous, high angle east-west faultsNôu^t to have been active during the Mesozoic Period. This Mesozoic^ûl^: system cuts the Champlain Lowland into a series of horsts and/grabens (Stanley, 1980). Stanley (1980) reports that these extensional faults are cut by alkalic dikes of early Cretaceous age (McHone and Corneille, 1980) . Bedrock has undergcmemSmyêformational events, and has undergone chlorite grade met*

Bedrock in the Champlain Lowland Aisually consists of carbonates (both limestone and dolomitic\mai:bles) and guartzite (Stewart, 1972) . Carbonates to the south tend to be coarse grained marbles, while to the ng. carbonates are of a finer grain, resembling limestone, (1972) asserts that these fine grained carbonates ha ^ome recrystallization and are therefore true marble es contain erosional features carved into bedrock, wh other localities these features are confined to the overlying s^ nts.

Sediments above bedrock are usually lake or marine detritus (see Figur |ind 3-7) , deposited within the last 6000 years following^ at of Wisconsin age glaciers (Stewart and MacClin The marine sediments were deposited as the glaciers m the St. Lawrence Valley, allowing saltwater to briefly f rom the Atlantic Ocean and form the shallow.

3-24

bed map based on detailed field mapping by Stevrart)

LL AND CLAY DEPOSITS FIG. 3-7 PINE STREET CANAL SITE

3-26 inland Champlain Sea (Fisher, 1980; Hunt, 1980). Isostatic reboun following the retreat of glaciers eventually dammed up the pasâ to the Atlantic, and the Champlain Sea reverted back to a freshwater lake named Lake Vermont. Figure 3-6 shows the position of the Pine Street Canal Site relative to the former lake. Hunt (1980) reports that there is little lithologic difêiênce between the marine and nonmarine sediments. Lake bottom s be fine grained, except in localities where ma the lake or sea (Fisher, 1980)., The Winooski the sea approximately 1500 years ago near Burlington (Versar, 1988). The marine sands of the underlay extensive areas of South Burlington.

Peat was formed in this area in ^lized, boggy backwaters. The composition of peat can vary n bogs, but as a function of depth within the same bo il fill, present at virtually any old, industrial area. Specially common near the shoreline and in boggy areas near Champlain. Former landfarming practices commonly involved the lling-in of wetlands.

3.4.3 Site Geology

Bedrock was found 9t a/dejath ^>^ 68 feet in well cluster MW3 (near the eastern ed^8kof^th4 site^, 166 feet in cluster MW4 (a little south of center)v 1^^ feet in cluster MW8 (near the southwestern edge of the siteV, and 170 feet in MW9 (near the northwestern edge). Bedrock at the site is a light red to pinkish dolomite, belonging to the interbedded quartzites and dolomites of the Cambrlam Monkton formation (Ecology and Environment, 1982). Bedrock was/roum!k arx a maximum depth of 68 feet in MW3C. Of the two wel4s cc^mpletep \n bedrock, one (MW9) showed good recharge after bai14^ng>swKilfe the other (MW8) showed extremely poor recharge. Tiiis Suggests the presence of fractures or the

3-27 development of secondary porosity in the bedrock. Bedrock is ne the surface north and south of the site. Supported by topog information, this has led to the suggestion that the site a filled paleo-drainage channel. East-west and north-south cross sections and location maps are presented in Figures 3-8 through 3-11.

Stratigraphically above the bedrock lies gravel or glacial till. This unit consists of g inches diameter, generally in a clay or silty s vas one veil screened in this unit (MW4B), and one completed in this unit and the overlying silt/clay (

The lover silt/clay unit consists of post-glacial sediments deposited vithin the last 6,000 yea^ffe>.,.^olloving the retreat of Wisconsin-age glaciers (Doll, 1970; ^te\«irtarKh-M^Clintock, 1969; Hunt, 1980). These sediments vary be^e^/Cl^tyey^ silts and silty clays, but tend to become more clayey vith d/^th. Both marine and non-marine sediments are present here, and\small bivalve shells vere observed near the southern edge of th« site. The thickness of this unit was found to be a maximum of 136 feet in MW9C and a minimum of 50 feet in he color of this unit is a mottled bluish, greenish, or gray. Readings from a pocket penetrometer indica etence of this unit varies widely, from 0.75 tof^ to over 4 tons/square inch, Occasional, apparently inuous, thin sand stringers are encountered in this These stringers reach a maximum thickness of five inches. Pieces of gravel become increasingly frequent as contact with bedrock approaches. Ten wells were completed nit during RI field activities (MWIB, 2B, 3B, 3C, 4A,/i OB^ lie, IID), one of which included the till below ('

3-28 N iilli!l§§i§§§§g8§ •rT\ s§sssss§ss§gsssss I I I I I I I I I I I I I

SCALE (FEET)

100 200 300 400

3-29 PINE STREET CANAL SITE EAST-WEST CROSS SECTION FIG. 3-9

MW3 (109.46)

nU: CUT/SILT ».. ^ PEAT LOWCR CUr/SILT g ^ CRAVEU COBBIXS. SANO BEDROCK W ^ nil: CRAVEU SANO, ASH • WSTAUED BT PCRKMS-JOmAN FOR HSL CIJEVATIONS IN PMCNTHCSCS N illil!i§si§§§gg8§ (D §§§§§§§§§§§§§§§§§ wuuHMrrwEET

SCALE (FEET) 100 200 300 400

LAKE CHAMPLAIN

Nb^T^SOUT H CROSS SECTION LINE FIG. 3-10 PINE STREET CANAL SITE

3-31 3-32 A sand unit was observed to overlie the lower silt/clay in northern portion of the site. South of NWll, the sand disappears as a distinct unit, although traces of it can s seen as sandy silt located just below the peat in the lower silt/clay. Jordan (1983, 1986) reported this sand to be wedge shaped, thinning eastward and thickening northward; and suspected that this unit extended below the canal and railrj tracks and possibly into the lake. Fluctuations in water ere seen during slug tests in MW7C from train traffi ing the interpretation that the sand extends under the 'ad tracks. Various investigations have interpreted the norther unit to be continuous with sand reported in borings on GE prop^^s^ at the southern edge of the site, however, borings in the canal failed to establish a connection between the two. A close examination of the GE boring logs reveals that this sand fill. Based upon the texture and geometry of the sa n (1983, 1986) suggested that the sand is a submerge bcalized channel deposit. Another plausible interpretat that the sand unit represents the southern edge of the WincJ Delta, a sand unit found just north of the site. An isopach of sand thickness is included as Figure 3-12. This map contours sand thickness, showing that the sand is thicke the railroad tracks (18 feet) and pinches out near the ^o f of the site. For reference purposes, a dotted o al complex and wetlands have been included on the i map. Two wells (MW7B and 9C) were completed in this unit.

Stratigraphically above the lower clay/silt (or sand, where present) is-^r-lrarge peat deposit. The peat appears to be a natural geologic /f ioitv occurring in the former Lake Champlain backwatet./ Aldri<;h\ (1978) reported the peat to be nearly 100 percent "b^^aftic and t/o burn readily when dried. It is dark brown and fibrous/Nand^n/Places contains stringers of silt or sand. It

3-33 1100 2100 I i I i ii 4000

3000

2000 2000

'''»''»'»' 1000 2100 ALL THICOfESSES ARX Df TOT

CH THICKNESS OF SAND UNIT FIG. 3-12 PINE STREET CANAL SITE

3-34 is composed of decaying organic matter, small tree stximps branches were occasionally visible. The peat reaches thicknesses of approximately 12 feet between the Bur* Electric Department and Maltex Pond, but tapers out near the eastem, western and southern edges of the site. The top of the peat is normally encountered between five and fifteen feet below the surface. There is a correlation between the thoci^ess of peat and the thickness of overlying fill material; in/place^^here the greatest thickness of peat is found there i

From the surface o. extending down to the peat unit (where present) is The fill material mostly resembles the lower in areas where the peat is absent the contact bet^ 11 material and the lower clay/silt is either difficult to esta or undefinable. This fill varies between clayey silts arid silty clays, while lenses of relatively pure silt or clay are common. Present in the fill are areas of sand and s r woodchips. In some of these areas the sawdust or woodc thick layer (five feet or more) which is diffic gu^sh from peat (the laboratory which tested the Shelby t at they could not make a distinction without first drying" pie in an oven). This difficulty affects the

~~3-35 /::i~~

~~1100 2100 II I I I I I 4000 4000~~

~~3000~~

~~- 2000 ~~

~~I I I I I I I I I 1000 2100 ALL TKiaOOSSES ARX DC TEXT~~

~~ACH THICKNESS OF PEAT FIG. 3-13 PINE STREET CANAL SITE~~

3-36 thic)cnesses of fill and peat reported in boring logs. Also in/th fill are tires, pipes, bricks, rocks, and concrete. Thickrv^sse of fill across the site can be seen in the isopach map f thickness (Figure 3-14). Seven wells were completed in this unit (MWIA, 2A, 5A, 7A, 9A, lOA, llA), two of Which included the peat below (MW2A and lOA).

~~3.5 Hydrogeology~~

~~3.5.1 Regional Hydrogeology~~

Bedrock is a major source of groundwater in the Norttteastem Appalachians. Fractured, non-porous bedrock is the most abundant lithologic unit in the region, although large well yields are reported more frequently from solubleHa^drocks (such as limestone or dolomite) than from any other tM>e•.>5£/^^'3rQck (Hydrogeology. 1986). This is probably a functionXoK f^actiir^^g and solution enlargement creating flow paths for theSgroimdwater, Faulting can also be responsible for high yields in betirotek. For example, well yields of 300 and 1000 gallons per mimi*^ are attributed to faulting in two wells which show uncharacteristically high yields. Characteristic yields wells in this area of the Green Mountains are four to minute (Stewart, 1973). Other sources of groundwat are from till, unconsolidated lake bottom sediment olidated sediments in stream valleys. Although not u widely as bedrock, coarse grained stratified drift deposits e most productive aquifers in the northeast Appalachians fHydrogeology. 1986). Water levels usually reach their highest point each year during the spring freshet, then decline d\^^ng_ th^growing season fHydrogeology. 1986).

~~3-37 ^~~

~~4000 4000~~

~~3000~~

~~ALL TgOPfEVrra A8I W TtXT~~

~~J ISOPACH THICKNESS OF FILL FIG. 3-14 PINE STREET CANAL SITE~~

~~3-38 3.5.2 Site Hydrogeology~~

-Groundwater near the Pine Street Canal Site is not a of drinking water nor is it used for other residential or municipal N. \. purposes; potable water in the Burlington area is obtained from \/ Lake Champlain. The intake for the Burlington Water Resources Department Plant is located approximately 7500 feetrsnorthwest of the turning basin. Nearby wells are industrial production wells which are completed in the bedrock aquifer at thf'G^, V^i^ing, and Blodgett plants.

There are four aquifers present at the Pine Stree€N^niH Site. The aquifers are only semi-confined, and can leak into those aquifers located directly above or below. The surficial aquifer is the uppermost aquifer and consis^^^ of the peat unit and overlying fill material. Stratigr^hicali^'"Sa^low the surficial aquifer at the southern half of the ^ire^lfe tji^lower silt/clay aquifer, while to the north a sand unit>aqui£er exists between the surficial and lower silt/clay aquifers. ^elW the lower silt/clay aquifer is the bedrock aquifer. \ /

The water level in tfre -ficial aquifer is three to four feet below the ground surf site. The water level in this aquifer decreases to :his gradient indicates that flow in the surfici fends towards the west, vith potentiometric surfaces a sating the outline of Lake Champlain (Figure 3-15). During the i elation of veil cluster MW2 at the GE facility, a water table was reached in the fill material, and the aquifer remained saturated until the bottom foot of peat, where it abrupt^ ended^ The underlying clay/silt unit was then unsatura^d/^for several feet, indicating that the peat and fill aquifer\is p^ched jatj the GE facility. This perched aquifer stems from extenfej^ye^nd /illing of the GE site in an effort' to fill in

~~3-39 1100 2100. ^~~

~~4000 4000~~

~~2000 2000~~

~~POTENTIOMETRIT^b^EJi^C SURFACE IN SURFICIAL AQUIFER FIG. 3-15 PINE STREET CANAL SITE~~

~~3-40 the wetlands. The weight of overlying fill has compressed/t: peat, resulting in a reduction of hydraulic conductivity Ajid causing it to act as an aquitard in this area.~~

The potentiometric surface of the surficial aquifer fluctuates between four to six feet each year, with water levels in theaquifer responding similarly to water level fluctuation! the canal (Jordan, 1984). Higher groundwater levels obsj ing the spring appear to result more from elevated canal, ring this period than from increased regional recharge, altl anal level fluctuations leave groundwater gradients relative onstant (Jordan, 1984). Jordan also interpreted groundwater f! in the peat to be westward in the southern portion of the site but to nose sharply to the north in the northern half, near the contact with an underlying sand aquifer. Jordan axtribtit^d this to a hydraulic connection with the sand body, and stateî^^that changes in hydraulic head in the peat parallel those in tlê \andf^ âter level data gathered during RI field activitiesX do6s not support this interpretation. The discrepancy may a^s^ from the relative scarcity of existing wells (and hence, data points) at the time of Jordan•s interpretation.

~~Hydraulic conduc e fill material range from 4.9 X 10*^ cm/sec to 3. (with an average of 1 x 10'* cm/sec) as measured by ting (PEER, 1990; Jordan, 1984).~~

Porosities in the fill material approximate fifty-five percent (Appendix G). A drop in hydraulic head of six feet over a linear distance of^'T^O'^Ceet is representative of the body of the site, yielding ya Iiy3i^lr9 gradient of .00857. Flow velocities range from .2/fe4t/day .3 X 10 feet/day at the extremes, with an average df,,^4.2vX ib"^/feet/day.

3-41 The hydraulic conductivity in peat vas found to be hi variable, vith values ranging from 1.9 x 10*"* cm/sec to 7.7 cm/sec (as measured by slug testing). The average hy conductivity is 5 x 10*-5 ' cm/sec

An extremely high value of .12 cm/sec vas recorded in veil MW3A, but since this value is so much greater recorded value, it is believed to be the result problem. With the hydraulic gradient of the (.00857), and assuming a porosity of 0.92 ( velocities in the peat are calculated to range f feet/day to 1.9 x 10*' feet/day vith an average veloci 10*^ feet/day.

Underlying the peat in the nort ortion of the site is a sand aquifer. The sand unit may be each deposit or be continuous vith sands of the Winoo nd north of the site, but data on the sand unit aquife acking to the north. During slug testing in MW7 (near the Malte ilding), fluctuations vere observed in the vater level of th^ sand aquifer vhich correlated to train traffic on the railroad tracks. This suggests that the sand extends belov\these tracks to the vest (it vas observed as far as MW8,/whe[rel--it contained a gravel layer) and quite possibly into/tH^ l^loerrv \his sand unit also has the potential to be in contact }A.th the turning basin or canal. The hydraulic conductivity ofN^hi^Nunit was measured to be 7.7 x 10*^ cm/sec by slug testing. Thfes/nydraulic head for this unit was observed to be lower than, either the overlying peat and fill aquifer or the-jinderlying silt/clay aquifer, suggesting partial discharge e aquifers into the sand unit aquifer. A minimum/6f is needed to determine a hydraulic gradient. Since on re screened in the sand aquifer, no hydraulic

~~3-42 gradient could be determined. This lack of a hydraulic grad makes it impossible to calculate flow velocities in the san~~

The potentiometric surface of the lower silt/clay aquifer trends towards the west-northwest (Figure 3-16). This potentiometric surface does not mirror the outline of the lake, indicating that the lake has less of an immediate im^ct upon this aquifer than it does upon the overlying su aquifer, Hydraulic conductivities in the lower silty^ fer (as measured by slug testing) range from 2.5 x 10 xcm, to 7.4 X 10*^ cm/sec, vith an average of 3.5 x 10*' cm/sec ydraulic gradient across the body of the site for the 1 It/clay aquifer is 5.12 x 10*'. The porosity of this aquifer approximates 55 percent (Appendix G). Groundvater flow velocities range from 6.2 X 10*' ft/day to 1.84 x 10*' ft/da^, ^ an average velocity of 8.6 X 10** ft/day. Vertical permeabiliti unit (laboratory tested) are similar to those of the p\Bat\an^ aquifer.

Few data points exist for the bedrockv aquifer. Two monitoring wells were installed into this aquifer during RI field operations, and no other bedrock monitoring wells exist in the vicinity of the site. The hydraulic co ity of this aquifer, as measured by slug testing in MW9C, i/sec. MW8 showed extremely poor recharge when baile urposes. This suggests the presence of fracture secoKdary porosity through which groundwater is flowing, i event the screen in MW8 failed to intercept any transmissive ures. As in the sand aquifer, a hydraulic gradient could not, be determined for this aquifer and no flow velocities-^could be calculated.

~~3-43 <~~

~~POTENTIOMETRIC SIJRFACE IN LOWER SILT/CLAY AQUIFER FIG. 3-16 PINE STREET CANAL SITE~~

~~3-44 3.6 Demography and Land Use~~

The Pine Street Canal Site is located vithin the city l^jdits of Burlington, VT, less than a half mile south of the center of the city. The site is in a mixed commercial, industrial and residential area. The population of Burlington is 38,275, according to the later census information.

The Pine Street Canal Site encompasses approkij^tely/80 acres of land (Figure 1-4) vith various p2irts of thV^site^ ovned by individuals, businesses smd local and state governmenrSs^ There are a number of active businesses operating on-site incl\ldjLng the Burlington Electric Department, Burlington Street Department, a General Electric manufacturing division. Citizens Oil Company, St. Johnsbury Trucking Company, and a sm building housing a restaurant, health club and several sm^ Pine Street, running north-south and forming the ea ry of the site, is lined vith commercial, manufac and residential establishments. There are residential co ties to the east and south of the site. An eighty-unit apartm complex, a public park, an elementary school nd several churches are all located vithin one half mile of e. Overall, the population around the Pine Street Canal terogeneous mixture typical of a developed urban are

Potable vater is supplied bV the city. Rav water supplies are obtained from Lake Champlain; wfere are no known domestic drinking water wells within one mile of the site. Several businesses in the area obtain groundwater from production wells for use in industrial processes/(e/gT>snonT^contact cooling).

~~The Canal Site has been an industrial area at least since €! 00's. Section 1.2.2 described the historical~~

3-45 uses of the land at the Pine Street Canal Site. Currently, are 17 Potentially Responsible Parties (PRPs) who are list former or current property owners of portions of the Pine Canal Site. Many of the current land owners are operating businesses at the site. The active businesses are along the streets that form the boundaries of the site. Several acres of the site were acquired by the Vermont Agency of Transport^Tb^on (VT AOT) in anticipation of highway construction (Sou Connector) through the center of the site. Figure 3-17 sho\^ oximate current legal divisions of the Pine Street Cana Table 3-8 identifies current owners of various land parcels am current uses of the land.

~~3.7 Ecology~~

Despite Its urban/industrial loc lation from other wetlands, the Pine Street Barge Ca a variety of wildlife. In a recent survey of Burl wetlands, the site scored 87 (of a possible 105) for g 1 wildlife habitat (Parsons, et al 1988).

The site is compose en water, marsh and shrub wetland. The U.S. Department of tional Wetlands Inventory (NWI) characterizes the si , open water and forested scrub-shr\ib deciduous , seasonal, or semi-permanent flooding regime. The site disturbed and consists mostly of fill. A large barrier to lake is created by the railroad embankment.

~~erface between water and land, provide a ,n addition to supporting a range of wildlife~~

~~3-46 il!iill§s§§§§§g§§ §§§§§S§§§§§§§§§§§ II I I I II I I I I I II I I I~~

~~SCALE (FEET) ^ "ia LOT 339 100 200 300 400~~

~~3-47 TABLE 3-8 OWNERS A2n> LA2n> DSE8 AT PINE STREET CANAIi SITE~~

~~Lot/Area Number Owner Land Use Lot 339 City of Burlington Burlington Street Dept. r(^fices and vork/s'^rage arei Lot 345 City of Burlington used but ce.~~

Lot 377 Citizens Oil Co. Active business. Lot 405 Louis Farrell Former PEPSI tling Co. Var3[ously used for ^^rage or retail business. Lot 431 Maltex Partnership Office building used by several small businesses, health club and restaurant. Lot 453 Empty field, no buildings, mostly tall grasses, some trees. Area 12<-69 Pine s^^tet Seune as Lot 453. Associal Area 12-80 Maltex Partnership Location of former coal gasification plant; no buildings currently on site.

~~3-48 TABLE 3-8 (Continued) OWNERS AND LAND USES AT PINE STREET CANAL SITE~~

~~Lot/Area Number Owner Land Use Lot 501 VT Gas Systems Gas transmission subs^^ion, fenc Lot 585 City of Burlington~~

Lot 609 City of Burlington Burlingtc Electric Department parking and work building. Lot 645 St. Johnsbury St. Johnsbury Trucking operates a king terminal 'the south half of the lot. The north half of the lot is densely covered by construction rubble and trees. A drainage area that connects to the canal is in the northwest comer of the lot.

Area 12-73 and f Vermont Lots purchased by Area 12-71 VT AOT in anticipation of highway cons trxict ion. Currently wooded fields bordering canal. Maltex Pond and southern barge slip are located in these areas.

~~3-49 TABLE 3-8 (Continued) OWNERS AND LAND USES AT PINE STREET~~

Lot/Area Nximber Owner Land Use Area 12-79 and Blodgett Co. Termination of Area 12-81 canal/And vetlands arei Area 12-82 and Lot General Electric ess. 128 Company Area 12-92 VT Railway Empt^ betveen canal ain embankmei Area 12-83 Davis Development Svampy area usually flooded by canal. Area 12-68 and BCV Associate py area Area 12-70 liy flooded by canal, vetlands. Unmarked lot on Blodgett Co. Active business southwest comer of site

~~3-50 populations. The barge canal nutrient retention and sto, capacity is potentially high. It is moderately effect trapping sediments; but groundvater recharge and dis functions are considered lov.~~

On-site vetlands vary from seasonally vet to in dated. Soil mottling and coloration (compared vith the Munsel lor charts) indicate generally hydric soils, although the va of fill make this characteristic less reliable. Vegetat^n e ranged from a predominance of obligate wetland plants (sp^oies hich have a greater than 99 percent probability of occurring in itli ds) to obligate upland (probability greater than 99% of the speclfes occur in nonwetlands). Table 3-9 lists the primary on-site species and includes the wetland indicator status for each.

The wetland delineation iden€ ative eastem boundary for the wetlands. Four categ wetlands, probable wetlands, probable upland, and uplan were used in the delineation. "Probable" indicates the gen' trend of evidence. which is inadequate to precisely identify wetland or upland. The boundary is continuous e for a break in the drainage ditch from Pine Street where vegetation borders the street. In another discontinuity e, east of the former coal gasification plant, s roportion of upland species. Essentially the entire save a proportion- of the eastern boundary, is wetlands.

~~3.7.2 Ecological Receptors~~

A s ade to locate two rare species of plants reporte Buffaloberry fSheperdi?i canadensis ) and Boarder M^ alictrum venulosum). Buffaloberry was known from an area e canal entrance, but the area is now covered

~~3-51 TABLE 3-9 ON-SITE VEGETATION AND WETLAND INDICATOR STATUS~~

~~SPECIES~~

~~TREES/SAPLINGS Silver Maple ABtr 5?~~

~~•INDICATOR CATEGORIES (Reed, 1988)~~

Obligate Wetland (OBI^). Occur almost always (estimated probability >99%)) under natural conditions in wetlands. Facultative Wetland^fFACW). ally occur in wetland (estimated probability 67-99%), but occasionally found in nonwetlaiids/ Facultative (FAC) occur in wetlands or nonwetlands (estimated probability 34%-66%).

Facultative Upland occur in nonwetland (estimated probability 67%-99%), but occasionally found in wetlands (est ability l%-33%). Obligate Upland fUPLV OcctiKin wetlands in another region, but occur almost always (estimated probability >99%) under natural conditions in nonwetlands in the Northeast.

~~•f\-. Indicates more/less frequently found in wetlands.~~

~~Species without an indicator status are not considered wetlands species anywhere in the country.~~

~~3-52 TABLE 3-9 (Continued) ON-SITE VEGETATION AND WETLAND INDICATOR STATUS~~

GRASSES, HERBS AND FORBS WETLAND 4N0IC A*FOR STATUS*

Marsh Horsetail Eouisetum palustre FACW Field Horsetail Eouisetum arvense FAC Cinnamon Fern Osmunda cinnamomea FACW Sensitive Fern Onoclea sensibilis FACW White Water Lily Nvphaea odorata OBL Broad-Leafed Arrowhead Sagittaria latefolia OBL Japanese Knotweed Polygonum cuspjdatum FACU Yellow Iris Iris pseudacorus OBL Broad-Leafed Cattail Trvpha latifolia OBL Eastern Bur-Reed Sparganium americanum OBL Giant Bur-Reed Sparganium eurvcarpum BL Reed Canary Grass Phalaris arundinacea FACW Blue-Joint Reedgrass Calamagrostis canadensis FACW+ Sedge QSISJLSPP OBL to FACU Flowering Rush OBL Butomus umbellatus FACU Daisy Fleabane Erjgeron annus Chicory Cichonum intvbus Butter *n Eggs Linaria vulgaris Queen Anne*s lace Paygvs g^rgta Common Yarrow Achillea millefolium FACU Black-Eyed Susan Rudbeckia hirta FACU Musk Mallow Malva moschata Blue Vervain Verbena hastata FACW+ Jewelweed Impatiens pallida FACW White Clover Trifolium reoens FACU Red Clover Trifolium pratense FACU Yellow Sweet Clover MelHgni»J?fficinalis FACU Common Blue Violet Purple Vetch FAC? Tall Buttercup FAC+ Black Nightshade FACU Field Mustard Goldenrod _jidagfi<5Pp OBL to FACU+ Yellow Avens Geu>n alenbi(Mim FAC White Avens Geum danad^se FACU Large-Leaf Avens Geum ma^rwhvllum FACW Common Mullein Verbascum thapsus Broad-Leaf Meadowsweet Spiraga latifolia FAC+ False Nettle Boehmeria cvlindrica FACW+ Ragweed Ambrosia SDP FAC to FACU White Woodsopfel/' Oxalis montana FAC Common Boneser Eupatorium perfoliatum FACW+ Moneywor^ C Lvsimachia nummularia OBL Silverwed \ ^ ^ Potentilla anserina OBL Trefoil ^ ^ Desmodium SDP FAC

~~3-53 with riprap that forms the base of the bike path and park. Nei species was located.~~

Three vegetative anomalies were discovered during the site survey. At the southem end of the site, in the "probable upland",a six to eight meter square group of shrubs (approximately two meters high) showed heavy insect damage and ^P^ few leaves remained intact. Several dead trees line the canz^ /The^^ape and growth form suggest Silver Maple (Acer sacchai4ntntt^ /Many are girdled and have wood chips surrotinding the basi^ig, indicating beaver activity as the probaible cause of demise. A th^rd ibcation, known as the "landing pad", is completely devoid of vegetation; the soil is stained blue-black at the center of the denuded area.

The vegetation survey identified^ al habitats on-site: the canal; emergent wetland; scrub-sh ested wetland; wooded; and herbaceous (grass/herb/fo habitats are delineated in Figure 3-18. Vegetation ical fauna found in each are described below.

The deeper portion^ the canal has little emergent vegetation; however, due) (] imna spp) and submergent vegetation are in evidence season^ }gs ai stumps dot the canal on which painted turtles fCh^set sun. Green frogs (Rana clamitans) also inhabit he anal edge. Fish species including minnows, rockbass (Amblopl es^yupestris), yellow perch (perca flavescens), pumpkinseed (Lepomis gibbosus), golden shiners (Notemioonus crvsoleucas) and northern pike (Esox lucius) and chain pickerel (Es€Sr~nlaer) enter the turning basin. Great blue heron (Ardea herodi:^¥T^labJc-crowned night heron (nvcticorax nycticorax) sr\(Ceryle alcyon) feed in the canal. Mallard (Anus pla1 ^ xerring gull (Larus argentatus), barn swallow (Hirundo rustica) \d tree swallow fTachvcineta bicolor) have been

~~3-54 N iiii tl 0 §§§§§§§§§§§§ MLauHMtmar~~

SCALE (FEET) 100 200 300 400 EwnaENTWcnAfe, tHMOUna, CATTAIU SCIIU»4HnUB WCUAND (JM) tiLvcn ANO HEO MAPLE, BuctcmoRNe, ALSEH, RED OSIER DOOWOOD, WIUOW POREtTEDWITUNO SILVER MAPLE, COTTONWOOD, ORECN ASt i ^ ORAM, HERBS, raiin fT-l WOODED C A COTTONWOOD, B. LOCUST, a ASK BOX ELDER, RED MAPLE, AMERICAN EUl

~~NOTE: PINE STREET CANAL ANO MALTEX POND SEASONAaV VEOnATEO.~~

~~UVKE CHAMPUMN~~

~~SPECIES HABITAT FIG. 3-18 PINE STREET CANAL SITE~~

~~3-55 observed in or over the canal. Dragonflies and damselfld (Odonata), mosquitos, gnats, and water stridors provide food ^ r many of these species.~~

Beaver also inhabit the canal. An active lodge is located midway up the canal on the westem bank. Gnawed trees are found throughout the site. Although not observed, muskrat/anfl racoon are also probably found here.

Emergent vetlands are dominated by cattails rTB;^ha/latifolia) and the common reed f Phragmites austral is). A neariv. pul!^ stand of Phragmites extends from the landing pad in a broad st^i|$ to the canal. Emergent vetlands are best developed at the southern end of the site and cemal, in a depression vest of the canal, and Maltex Pond. Painted turtle and/sn2[ppLing turtle (Chelydra serpentina) have been observed in \hi^^-Jiabitat^and red-vinged blackbird (Agelaius phoeniceus) nest

Scrub-shrub wetlands by definitionV a^e characterized by vegetation less than six meters in height, silver maple, red maple (Acer rubrum), European buckthorn (Rhamnus francmla), speckled alder (Alnus rugosa), red osier dogwood (Cornus stolonifera) and willows (Salix spp) liredominat^v. This habitat is primarily adjacent to the cana3(^and,,jiiucK'~'6ftne avifauna that utilize the canal for feeding find cover 4iere.

Also adjacent to the canki are forested woodlands dominated by silver maple, green ash (Fraxinus pennsylvanica) and cottonwood (Populus delt:oldes) greater than six meters in height. Kestrel (Falco spz^ryerlus) \nest in a snag on the canal. Understory consists/of

~~3-56 (Picoides pubescens) also nest here. Several ribbon s (Thamnophis sauritus) were observed in this habitat.~~

The wooded areas are also dominated by trees (> 6m.). Here, however, a larger variety of facultative species - cottonwood, green ash, red maple, box elder (Acer necmndo), American elm (Ulmus americana) - are in places interspersed with blackylo^st (Robinia pseudoacacia), a more upland species.

Open herbaceous areas are dominated by grasse uals and forbs. In a dense thicket of Japanese knotweed ygonum cuspidatum) near the Burlington Electric Company, a cecropia moth (Hyalaphera cecropia) and a dead red fox (Vulpes fulvft) were found. Although the cause of death could not be...4^^3^™^'^^^ (the animal was too badly decomposed for rabies analysisL^ twd^-ether mammal remains were found on-site; a groundhog and a

Groundhogs (Marmot?^ monax) were a>ctiVe in the northern, western embankment, and southem portions o!^/the site. Adults and young were seen. Although not observed, racoon and muskrat probably also frequent the~~'^te. A variety of passieriformes (songbirds) were observi^ J5p\o4^^te personnel. Table 3-10 lists avifauna observed during/xheycoufse'^ the Remedial Investigation.

~~3.7.3 Sampling Activi~~

Macroinvertebrate samples did not undergo taxonomic analysis. However, only a few snails were evident during collection. Based on this irrformation, the canal apparently does not support a diverse benthic faunl

~~TableN3-l es^nts fish sampling results. A total of 108 fish were nett the canal in two sets; 88 were captured at the~~

~~3-57 TABLE 3-10 AVIFAUNA OBSERVED DURING THE REMEDIAL INVESTIGATION~~

Mallard AT)US pi^tYrhvn American Kestrel Falco sparver Great Blue Heron Ardes herodi Green Heron Butorides st_ Black-Crowned Night Heron Nvcticorax nvcbicor Killdeer . Charadrius vocifCTi Herring Gull Larus argentatus Rock Dove Columba livia Mourning Dove Zenaida macroura Belted Kingfisher Carvle alcvon Common Flicker Colaptes auratus Downy Woodpecker Pi6o3:des pubescens Eastern Kingbird T<^ranr{us êv^^qnus" Eastern Phoeve Sô^pTS-sphoev^ Barn Swallow HirHr;d\^ Tree Swallow Tachycinetâ bicolor American Robin Turduk mjgratoritis European Starling Stumuk vulgaris Yellow Warbler Dendroica/petechia House Sparrow Passer domesticus Red-winged Blackbird Agelaius phoeniceus Common Grackle Ouiscalus guiscula Northern Cardinal Cardinalis carinalis American Goldfinch Careulis tristis

~~3-58 TABLE 3-11~~

~~FISH SAMPLING RESULTS~~

~~Mid-Canal Cana] Entrance La Platte Marsh~~

~~Generalized Feeders Golden Shiners 73 20 (N?t?miRonus crvsoleucas) Brown Bullhead ~— (Jsiaiiiiiis. nvbviQsus) Percent of Catch 9I<) 71%~~

~~Insectivores Pumpkinseed 1 (Lepomis gibbosus) Yellow Perch 2 (P?rca n?vf5«ns) Percent of Catch 4%~~

~~Top Carnivores~~

~~Chain Pickerel — 1~~

~~Northern Pike — 4 (Esox lupju?)~~

~~Rock Bass 4 (Ambloplites rupestris)~~

~~Percent of Catch 11% 10%~~

3-59 control site. Golden shiner (Notemioonus crysoleucas) was the abundant species netted. Species diversity was highest control area La Platte River marsh (7 species) and lowest ii^ canal (4 species). Brown Bullhead do not inhabit the canal and the generalized feeder trophic level is composed entirely of golden shiner. Based on catch data, the canal has a lower percentage of insectivores than the control area. The top camiv^eyan the canal is rock bass (Ambloplites rupestris), although c^jai/i pj^k)erel and northern pike apparently frequent the turning b

All rock bass netted in the canal had a red circular Tungus- like growth near the caudal peduncle. None of the control group had this anomaly. Other than injury due to netting, there was no additional external evidence of tumo):s or disease in the canal fish.

Approximately two-thirds of the s aught in the center of the canal were less than 15 centimet .whereas less than 15 percent of the control group were in this gth class. The two perch caught in mid-canal were juveniles. These limited data indicate the canal may nursery for some species. For additional catch data, collection report submitted to the Vermont Agency of Nat ROSS, 1989).

~~3.8 Field OA/QC Procedu~~

~~3.8.1 Quality Control Samples~~

~~f quality control samples were collected sampling program; these were field blanks, equipment rinsate samples and duplicate~~

3-60 Field blanks vere used to assess the degree, if any^, contamination generated in the field and potential contamination betveen samples occurring during sample coll or preparation/packaging. Field blanks vere prepared and carried by sampling teams throughout the day, along vith other samples collected during the day. They vere analyzed Xpr the seune parameters as the samples they vere collected vi

Distilled vater blanks vere prepared and &entN^ lahs along vith other vater samples. These samples vere^prepared using commercial distilled vater and vere analyzed for all pa)^^ebers for vhich field samples vere being analyzed. They vere used to provide a check on sample preparation and handling by field and laboratory personnel. Distilled vater blanks ver/a^sent at the rate of one for every 20 samples.

~~Equipment rinsate samples vere \ c from sampling equipment after decontamination. These es vere collected to determine the adequacy of decontaminat procedures betveen collection of samples.~~

Duplicate samples lected at the rate of one for every 20 samples throughout^ rts. Duplicate samples vere analyzed for the s as the original sample. Analytical data from thes es vas used to determine laboratory reproduc ib i1ity.

Reviev of analytical data from these quality control samples indicates that no^^mpounds other than laboratory contaminants vere detected yiri/any^f ^he samples. Quality control samples vhich contained fab contaminants were properly qualified.

~~3-61 3.8.2 Sample Custody~~

Each sample shipped to CLP laboratories for processing vas properly documented to ensure complete and accurate analysis for all parameters requested, and to support use of sample data in potential enforcement actions conceming the site. Kê EPA Region I system of documentation provided the means oy tracking each sample from the time of collection through finayd^â êpbrting.

~~3.8.3 Field Logbook~~

The field logbook is a controlled evidentiary document and vas maintained accordingly. Field logbooks provided a means for recording all data collection activi^ti^s performed at the site. Entries were as descriptive and detailedas"~-^Q§sible, so that a particular situation could be reconst3ns,ctVdyitJveuj: reliance on the collector's memory.

All measurements made and samples cd^ected were recorded. All logbook entries were made with indelible black ink and legibly written. No erasures werC~{>^rmitted; if an incorrect entry was made, the entry was ^Q^s>«^d L,QUt with a single strike mark, initialed, and dated..

~~3.8.4. Equipment Decon~~

All equipment used to collect samples (spoons, shovels, bailers, submersible pumps,.etc.) was decontaminated prior to and followin•*-"'•'"" g ^---..-v— Qf each sample. The following decontamination procedure id:

~~o detergent o potable water~~

~~3-62 o rinse with isopropol alcohol o rinse with distilled water~~

Large sample collection equipment (augers, drill rigs, etc.) vas rinsed with a high pressure vasher. All decontamination liquids generated on-site vere containerized in 55/^llon drums; these drums remain on-site. Drums at the site are jQl/coinsolidated in the decontamination area.

~~Clean, surgical and/or nitrile gloves vere personnel decontaminating or otherwise handling sampling~~

~~3.8.5 Sample Collection and Identification~~

Samples were collected in specf ottles obtained from the CLP Sample Bottle Repository.^ ely ten percent air space (except for volatile organic es) was allowed for water samples so that the container was ri ull at 130"F.

Samples were collected using clean, decontaminated sampling equipment, and placed iimRifediately into sample containers. Clean surgical and/or nitrile/^oves.. were worn by all personnel collecting or otherwise i^andlin?^sables.

A coding system was ^isedXto identify each sample collected during the sampling programXy This coding system provided a tracking procedure to allow retrieval of information concerning a particular sastpXe and ensured that each sample and sample location was unique^Ly J^nti^ied.

~~Eac ion identification number was composed of three compd are described as follows:~~

~~3-63 Project Information - A two-letter designation used tso identify the same collection site. For the Pine Stre^ ^Sh^ \^ Site the designation was "PS".~~

~~Sample Type - A two-letter designation used to identify the specific type of sample being taken. The sainple types that were collected during the remedial site invea^iqation were:~~

o SS - surface soil sample o DS - dioxin soil sample o SD - sediment sample o SW - surface water sample o MW - soil boring sample from monitoring well location o BO - soil boring samj^le o AS - air sample o EB - equipment blank o FB - field blank o TB - trip blank o BS - off-site background soil sample o GW - groundwater sample

Sample Number - esignation used to number the sample within ^ The samples were numbered consecutively withi sample type and were not related to the date of collectio "D" following the sample number indicates that the sample was a duplicate sample for that location. Well clusters were numbered 01 through 10 with a lette;?'''as~a"^ffix designating individual wells. "A" always denotes'^^H^shallowest well.

~~PS-SS-001) formation - Pine Street Canal* Site~~

~~3-64 Sample type - Surface Soil Sample Sample number - First surface soil sample colle(^e~~

~~3.8.6 Sample Container Labelling~~

A separate sample tag was completed and secured^o each sample bottle to be analyzed. The sample tags were suppl y EPA Region I and met specifications in Characterization o us Waste Sites A Methods Manual. Volume I. Site Investige PA/600/4 84/075, April 1985. The following details vere ed on each sample tag:

Project code (case number designated by the Contract Laboratory Program). o Station number. o Month, day, and year. o Time sample vas collected. o Designation of whether the sample^as grab or composite. o Sample location. o Signature of sampler. o Indication of wjiether the sample was preserved. o Indication of/che~±ype of analyses to be performed on the sample.

~~3.8.7 Chain-of-Cust~~

A chain-of-custody record was completed for all samples requiring laboratory analysis. Custody seals were affixed to each sample and ^Ceach sample shipping cooler. The chain-of-custody records were" &uppried by EPA Region I and met or exceeded specifications in\:haracterization of Hazardous Waste Sites - A Methods wantJal^ Vqlunle I. Site Investigations^ EPA/600/4-84/075,

~~3-65 April 1985. The following details were included on the cha^-o custody record:~~

o Project name. o Signature of sampler. o Station number (sample code) for each sa: o Date of sample collection. o Time of sample collection. o Indication of whether sample was gra osite. o Description of the sample collection stet o Total number of containers. o Number of each type of container under the corresponding analysis, o Sample tag numbers, o Airbill number.

~~3.8.8 Sample Shipping~~

~~When sent by common carrier, the p^bc^aging, labeling, and shipping of hazardous wastes and substances is regulated by the U.S. Department of Transaorta$:ion (DOT) under CFR 49.~~

~~Samples collect ne Street Canal Site were classified as enviro Environmental samples are those that contain of contaminants and require implementation of limited p tionary procedures.~~

Sample containers were .enclosed in clear plastic bags through which sampW'^ags^^d labels were visible. Dioxin samples or those suspected/to^^coi^tainv dioxin were enclosed in metal paint cans or placed i(n rwo plasnicj bags. The outer metal can was labeled with the numbe^Nof the s^mi^le contained inside. All samples were packed in plastic orNnetal/coolers, surrounded by vermiculite.

3-66 For the following sample types, ice was used to co(^ sample to 4*0: water samples for low- or medium-level analysis; water samples for low-level inorganics analysis; and all cyanide samples. All other samples were shipped without ice. Low- and medium-level water samples fbr volatile and inorganics analysis were preserved as directed by Region I. /V

Samples processed through the CLP were packa^d for/shipment in compliance with current U.S. Department of Transpbrt^ion (DOT) and commercial carrier regulations. All requireo^gcveinment and commercial carrier shipping documents were filled out and^hipment classifications made according to current DOT regulations.

~~Traffic Reports, SAS Packing Lis .^hain-of-Custody Records, and any other shipping/sample do ^companying the shipment were enclosed in a waterproo '^nd taped to the underside of the cooler lid.~~

Coolers were sealed with custody seals/in such a manner that the custody seal would be broken if the cooler were opened. Shipping coolers had cl isible return address labels on the outside. Samples for nic and inorganic analyses were shipped "Priority ,to avoid compromising the integrity of the sampl 1 samples were shipped through a reliable commercial ca such as Federal Express, Emery or Purolator.

~~3.8.9 Analytical Data Validation~~

~~analysis, sample data packages were sent to alidation. Metcalf and Eddy, under contract reviewed each data package for completeness~~

~~3-67 and accuracy. Guidelines followed for data validation of SAS data are for Data Quality Objective (DQO) Level IV.~~

Validated data packages included analytical data with data qualifiers and case narratives describing any analytical problems or data limitations. Data qualifiers associated vith the analytical data are defined in Section 4.0. VajAd^ted data vas transmitted to project staff both in hard copy ^d y6n^ computer disk.

~~3-68 4.0 NATURE AND EXTENT OF CONTAMINATION~~

Past activities at the Pine Street Canal Site have in the potential for. contamination of air, soils, surface vater and groundwater. The primary source of information for the assessment of contamination in these media is the chemical ana^sis of samples collected during the Remedial Investigation, ormation from previous investigations is used to support data uring the RI. Any chemical analyses from previous ations are considered unvalidated data and their use will in this report.

E This section presents the results of the geologic, hydrogeologic, soil, sediment, surfac^water, groundwater, air and biological investigations. The discussi^T-ofresults is divided into subsections, by media. Summary\ta^le§^j3.sting number of samples per media, compounds detected\ freqaency of detection for i each compound detected, concentration rimg^s, and location of the maximum concentration are presented in\/each subsection. In C addition, a subsection summarizes the results of blank sample t analyses. Appendix D pres ed summary tables showing each compound analyzed fo' tions of each compound detected in each sample, the liro etection for each compound and data qualifier codes. Data qua codes are defined as:

~~U compound was not detected, detection limit is presented. the detection limit is estimated. he data is rejected.~~

~~4-1 the associated numerical value is an es quantity and this data should be us caution.~~

~~In addition, a second set of summary tables shows only the compounds detected for each sample. This table uses only non qualified or J values.~~

~~4.1 Blank Samples~~

Sampling devices and analytical equipisiatit ^ e re-used. Decontamination of equipment between samples ma^v nob. be 100% effective, and small amounts of residue (from previous^samples and from reagents used to clean eguipment, such as acetone) may remain and be analyzed with subsequent samples, In addition, equipment may become contaminated (during sto use) with small amounts of material other than from the sa en (e.g., due to vapors in the laboratory, dust, etc.)> re, the containers used to store samples may be contam\na d. To determine the significance of such residue, blank s re taken and analyzed.

Equipment blanks are taken by rinsing field sampling equipment with double-distilled d collecting the rinsate in bottles identical to those us/d samples. Field blanks are taken by filling sample le-distilled water and taking the bottles into along with the bottles used for sampling. Lab method are conducted by the analytical laboratory by analyzing nant-free water that has never been exposed to field conditions.

~~ks, field blanks and lab method blanks which a specific sample group submitted to the lared to the actual site samples submitted in a validator. The following actions were taken~~

~~4-2 by the data validator after comparing the concentration chemicals detected in the blanks to the concentrations of t| chemicals detected in the site samples:~~

~~o If a chemical concentration detected in the sample was less than the Contract Required Quantitation Limit (CRQL), the chemical was reported "as njot^ detected" (U qualifier).~~

An action level was developed based 6Q th^ cpncentration [ of a chemical detected in a blank. If^t}^ ct^emical was a common lab contaminant (acetone, methyleh*^ ^loride, L phthalate esters, etc.), the action level was set at ten times the concentration detected in the blank. If the [ chemical was not a commoiwlab contaminant, the action level was set at five ti^es^thelrsncentration detected i in the blank. If the concentration of a chemj-cal detected in a sample C was greater than the CRQL but lek^than the action level, the chemical was reported as not detected (U qualifier) [ in the sample.. [ If the cong'e chemical detected in a sample was greate L and greater than the action level, the 1 was reported at the detected [ concentration, uri Ified.

I As previously stated, the data validator only compared blank results to/£hes^fecific sample group with which they were analyzed; further >6om6ari^ns\ of sample results to applicable blanks are presented'^ this ^selction. Tables 4-1 and 4-2 show the highest observed OQnc^tra^ipns detected in blanks associated with soil and

~~4-3 TABLE 4-1 HIGHEST OBSERVED CONCENTRATIONS IN BLANK SAMPLES FOR SOIL PINE STREET CANAL SITE~~

~~Max. Concentration Conteu&inant Observed (ug/kg) ank Type~~

Volatiles •Toluene 3.0 ipment blank •Acetone 58.0 II N Benzene 2.0 Semi-Volatiles Phenanthrene 3.0 Equipment blank *Bis(2-ethylhexyl) phthalate 798.0' •• 11 •Butyl benzyl ' phthalate 264.0 Jnorqanios Iron Equipment blank Lead II II Aluminum tl II Calcitim II n Arsenic n II Magnesium II II Manganese n 11 Zinc n If Silver II II Barium n n Nickel n II Chromitim n II Potassium n II Cobalt tl n Sodium II If Coppe; It II Vanajc n It Ant II 11

~~Commo ry Contaminants (EPA, OERR, Dec. 1989)~~

~~4-4 TABLE 4-2 HIGHEST OBSERVED CONCENTRATIONS IN BLANK SAMPLES FOR WATER . PINE STREET CANAL SITE~~

~~Max. Concentration Contzuninemts Observed (ug/1) Lank Type~~

~~Volatiles~~

•Acetone 120 EqiH jjment blank •Methylene Chloride 13 S. *s \ " II Carbon disulfide 58 > ^ Inorganics Calcium 673 Field blank Iron 11.Q II If Lead 3-? II II Magnesium 57.6 It It Manganese 4.9 II tl Sodixim 214 tl tl Antimony 23.9 H N Zinc 38.4 tt tl Altminum 105 tl II

~~Common Laboratory nants (EPA, OERR, Dec. 1989)~~

4-5 water sampling. Further comparison of sample results to b^ will be consistent with the procedures of the data va] described above. If a common laboratory contaminant is in a sample at less than 10 times the concentration detect^ applicable blank, it will not be considered site-related. If anon- laboratory contaminant is detected in a sample at less than 5 times the concentration detected in an applicable blank,/s^t will not be considered site-related. r 4.2 Contaminant Source(s) The major source of both organic and inorganic^'Xonttimination at the Pine Street Canal Site are process residues from operation of the manufactured gas plant from 1908 until 1966. Volatile organics (benzene, toluene, ethylbenzene, xylenes), semivolatiles (mostly 2-6 ring PAHs), and inc>rgariicS^~.-X|aetals and cyanide) i associated with process wastes from\;oa^""âs manufacture are found at various concentrations in different\meâ/over most of the site. The major area of subsurface soil and\gr^ndwater contcimination [ covers approximately 38 acres of the 80âcre site. Groundwater, surface water, soils, sediment and air all exhibit some degree of [ contamination. The cont^Hvination appeared to have resulted from common, historical pra disposing of process wastes on-site [ and in the back wat :lands and from the day to day operations of an r racturing plant (i.e., leaks, r inefficient equipment. )er maintenance). Because the entire 80 acre site is and has always been an 1 industrial/commercial area, there are other areas of the site that are possible sources of contamination that may or may not be distinguishecSTfes^rbm the overall contamination of the gas plant site. /Fo£ exampiV* \in 1986 the former fuel storage area at the north eiM., ofXthe /si;ce had a documented No. 2 fuel oil spill of

4-6 20,000 gallons. Number 2 oil has many of the same constitu MGP process wastes and, with the possibility of mixin diesel with already present gas plant wastes, it would be d£ to distinguish between the two contaminant sources. In the same situation, some of the organic contamination at the southem end of the site may be related to business activiti^ of the St. Johnsbury Trucking Company. The General Eleorr/c Compan y is undergoing a RCRA facility assessment (see prey tigations discussions in Section 1.2.4). While the GENpro^ does have organic and inorganic contamination associated wi^ gas plant site, there is also chlorinated organics contaminatidlvth^t is not related to gas plant operations. There are also various, minor 1^ point sources of contaminants (solvents, pesticides) that are associated with any industrial area.

~~As stated in the introduction t scope of the RI il was restricted to determining ure and extent of contamination originating from the anufactured gas plant.~~

~~[ 4.3 Air Monitoring~~

[: Air monitoring co d)at the site can be divided into two types, real time per g and ambient air monitoring. [ Real time personnel isted of using direct reading hand-held instrumentati ile ambient air monitoring involved [ drawing a known volume of hrough a sorbent media which was then analyzed in a laboratory.

~~I 4.3.1 e Personnel Monitoring~~

~~soVinel monitoring was conducted using a flame ionizatio FID) and/or a photoionization detector (PID). The FID used oxboro Organic Vapor Analyzer (OVA) Model 128,~~

~~4-7 and the PID was an HNU model PI 101 equipped vith a 10.2 e; Both of these instruments detect volatile organic vapo parts per million (ppm) range.~~

Real time personnel airborne contaminant monitoring conducted during the field reconnaissance trip of April 17^^1989 indicated no concentrations above background for measurable organic compounds. This information alloved non-intrus^/ve/ii^d^ctivities to be performed vithout respiratory protection

During veil drilling activities, above backgrdtiqd Revels of organic contaminants were detected on real time instrtiments at li; three locations. Well locations MW-11 (southern barge slip) and MW-3 and MW-4 (coal gas plant area) Jjad detectable levels venting from the boreholes ranging from 1.^ to l^T-ppjp on the HNU and 10 100 ppm on the OVA (Figure 4-1). i Readings taken directly above boi;eh6J.es with the OVA were [ generally an order of magnitude higher than/the HNU due to the lack of methane detection by the latter instrument. The HNU does not detect methane because theônization level of methane is above [ that of the 10.2 eV p^be-susfed. Readings in the breathing zone were generally less lân lyO ppmN^th occasional ceilings of 2.0 r ppm depending on wfnd alyeclfionv.v Drill rigs were configured to allow adequate ventilation >si^ the borehole. See Figure 4-1 for drilling locations and râil Ifeime air monitoring contamination readings.

Durinj boring activities, ten locations had above backgrouj s detected on the HNU and/or the OVA. Soil boring 07, B09, BOlO, B012B, B016, B017 and B022 (Figure elded real time concentrations o^ airbome contaminant ackground. Most of these borings were in the

~~4-8 N iilii!l§§gs§§gg§§ §§§§§§§§§§§§§§§§§ WtBUHWrrHEET~~

~~REALTIME AIR MdNJtORING ATSELECTED DRILLING LOCATIONS. READINGS IN PPM IN THE BREATHING ZONE FIG. 4-1 PINE STREET CANAL SITE~~

4-9 coal gasification plant or southern barge slip area. BO-o; BO-017 were in the barge canal. Similar to the well lo? ingeneral terms, readings around these boreholes were 1.0 on the HNU and 10-100 ppm on the OVA. Because of the rapid dispersion and dilution of contaminants in the air, levels in the breathing zone were generally less than 1.0 ppm but occasionally reached a maximum of 2.0 ppm.

Well purging and sampling activities vfer< odndticted from October 1989 through March 1990. This fieldv worj^ was also r monitored using the OVA and HNU instruments. AllN^el^s vith the exception of MW-llA, B102, B104 and B105 produced cohcywitrations I of less than 1.0 ppm in the breathing zone on both instruments. .Volatile organic emissions from MW-llA, B102, B104 and B105 (Figure I 4-2) ranged from 1.0 ppm to 5.0 ppm; these values are only estimates because the ambient air vere 40 to 50*F 0 belov the standard operating range 'the HNU and OVA. Ambient air temperatures during Decemb e routinely belov O'F. The minimum operating temperature as s ied in the operating c manuals is 50'F for the OVA and 35'F for t HNU. Figure 4-2 shovs veil locations and estimated real time airborne organic contaminant [ emission concentrations, ells yielding elevated levels (above background) of org purging and water sampling [ activities. As wit adings, these elevated levels were at the southern slip and the coal gasification [ plant locations. 4.3.2 Ambient Air Monitoring \ f ambient air sampling for semivolatile organic successfully completed, however, total semi s cannot be directly compared between rounds. analyzed for complete semivolatiles while the

~~4-10 N il!il!lg§i§§§§g§§ T ^ SSSS8SSSSSSSS8SSS MJUWwrTtEE T ^ I I I I I I I I II I I I I I II~~

~~SCALE (FEET) 100 200 300 400~~

~~WELL LO5CATl< 5 NS AND ESTIMATED REAL TIME AIR MONITORINJGVALG LUEl S DURING PURGING AND SAMPLING FIG. 4-2 PINE STREET CANAL SITE~~

4-11 second and third rounds were only scanned for PAHs. The round excluded analysis of 2-Methylnaphthalenewhich was de;i to' be the second most abundant PAH in the first two rounds. Because of the nonuniformity of the analyses, a direct round-to-round comparison is difficult.

~~Two rounds of volatile sample collecizl were also successfully completed and will be discussed be^o~~

The first round of air sampling began at 133.0 ho-.,organics detected only chloroform in the three primary collSfition tubiss and the blank. Two of the primary tubes were run^ i)v pa(rallel to collect a duplicate sample and revealed the samevre/ults. In addition the blank contained no compounds except chloroform. The concentration of chloroform in the primary tubes was less than that detected in the matrix spike; therefore, chloroforTn is believed to be present due to laboratory contamination. The only other volatile organic compounds detected were/xomid^^hs^ backup tube. The contaminants were benzene, tolue/ej^^^t^l/B^Jiizene and total xylene; all, with the exception of totalsxyl^ne, were also detected in the matrix spike. It is believed^tl:iatN:he backup tube contamination and chloroform detection wer^^ direct results of laboratory contamination and that no site-related volatile organic contaminants—we;^ present during this round of sampling (Table 4-3).

~~Rd olatile analyses indicated the presence of thirteen c eight of which were PAHs. The remaining five~~

~~4-12 TABLE 4-3~~

~~AIMUltlNl AlK VULA iiLt Ar>lALYdC a - < (ng/Sample Tube) \ yX N ROUND ONE \ > ,~~

~~Sample Tube Number Compound CRQL 001 002 003 003B^ ^00. 005MS 1~~

8U Heptane 6U 7U 5U / ^ 1 I-heptene 5U 5U 5U >/ / / S\i 5U 1 Chloroform 4J 5U 4J ^^V K5 ^ /W 6J l,2,dichloroethane 5U 5U 5U ^ SIT 5U 1,1,1-trichloroethane 14U 25U 15U lOUNv26l K 15U Carbon tetrachloride 5U 5U 5U 5U ^«y > 5U l,2,dichIoropropane 5U 5U 5U 5U 5U>/ 5U Trichloroethene 5U 5U 5U 5U 5U 160 J Benzene IIU 12U lOU llOU 7U 190J Bromoform 5U 5U 5U 5U 5U 5U Tetra chloroethene 5U 5X1 5U 5U 5U 5U Toluene 28U /lU ^ ^4ay 810J 46U 380J Chlorobenzene 5U \51V> 50^ ^40U 5U 170 J Ethyl benzene 5U \U\ ":?U/>^ 27bJ 5U 8J Xylene Total 30U 2iu ^\26U ^ T500J 15U 16U 1,2,dibromomethane 3U 3l \ ^It 3U 3U 3U Isopropyl benzene 5U 5U\ $U 27U 5U 7U Bromobenzene 3U 3U ^ 3U 3U 9J 1,3 dichloropropane 3U 3U \ ^ 3U 3U 3U

Dilution Factor. 1.0 1.0 1.0 1.0 1.0 / J»^'•° Date Sampled 7/24 1/2A 7/24 7/24 7/24 / / ) W Date Analyzed: //^}K./7/3 1 7/31 7/31 7/31 7/31 \ " Sample Tubes 001,002, 003 were^ttdmar^ollection tubes 003B was a back-up tul> v > 004 was a blank \ / OOSMS matrix spike

4-13 compounds were 1,4-dichlorobenzene, benzoic acid and phthalates which are believed to be laboratory conte Total PAH concentration was most abundant (0.395 ug/m') at AS-002, the former coal gasification plant. Naphthalene, followed by 2-methylnaphthalene had the highest concentrations. Sample AS 003 collected just east of the filled-in southem barge slip had a total PAH concentration of 0.214 ug/m'. Samp -001 located farthest from any known hot spots, had th amount of contamination (0.130 ug/m'). Table 4- down PAH contaminants for Round One samples and Fi 3 indicates location and total PAH concentrations.

Round two samples were collected on October 24, 1989 during drilling activities. A well cluster was being installed at the location of the filled-in south;^rrr"~i>a3:ge slip where visual contaminants were present. Volatile J^mpl^s frbjn this round were not validated due to laboratory coivtaiiî^'blon; A PAH scan was i performed on the semivolatile fraction rndi/ating naphthalene again as the most abundant contaminant and 2êtthylnaphthalene as the c second most abundant. Highest concentrations (0.398 ug/m') of PAHs were detected in sample AS-005 the most downwind sample. Table I: 4-5 lists PAH concentrations by compound. Figure 4-4 depicts sampling locations ana total coJtcentrations for PAHs. C Round three samplfeswerfe collected during the most unfavorable E meteorological conditionsXi«ev, temperatures between 10 and 20'F and winds gusting to 30 mpnr Volatile samples were collected November 30, 1989 and semivolatile samples were collected for a 24 L hour period^-endîîg December 1, 1989. Measured concentrations were very low volatiles and semivolatiles at all monitoring locatio ite the fact that drilling operations were occurr ighly contaminated part of the canal, meteorolog tions were not favorable for ambient air

~~4-14 TABLE 4-4 AMBIENT AIR SEMIVOLATILE ANALYSES (ug/m') ROUND ONE~~

~~Sample Location Compound AS-OOl AS-002 AS-003~~

Naphthalene R 0. 230^ \y /0.066 2-Methylnaphthalene 0.080 0. 100 ^\ / 0.032 Acenaphthene 0.012 0. 015 N. \0.006 Fluorene 0.012 0. 013 \ ^ 0>006 Phenanthrene 0.021 0. 028 \/.009 Anthracene R R 0.095 Fluoranthene 0.003 0. 006 R Pyrene 0.002 0, 003 R

~~TOTALS 0.130 0.214~~

~~R - Data rejected during validation prices, monitoring. Strong winds in a north/souBhyiirection and very low temperatures contributed to low emissionsMnd high dispersion~~

~~4-15 N il!ii!l§§i8si88i§ rf\ s§ssssss§§s§ssss§ WLBUWN rmEET~~

~~I I I I I I I I I I I I I •S-fOO~~

~~SCALE (FEET) •1-t-OO~~

~~100 200 300 400 O-fOO~~

~~1-«-00~~

~~2-fOO~~

~~3-fOO~~

~~LAKE CHAMPLAIN 4400 s+oo •+00 74-00 • -fOO~~

~~••••oo~~

~~lO-t-OO~~

~~11+00~~

~~METEOROLOGICAL DATA F 12+00 WIND DIR. FROM THE' 13+00 WIND SPEED 0-1 mph 14+00 TEMP 73-85°F 15+00 HUMIDITY 67% 16+00 BAROMETER 33 17+00 18+00~~

~~1»+00~~

~~20+00~~

~~21+00 BUnUNOTON ELECmC 22+00 DEPT. 23+00~~

~~24+00~~

~~uossrmjEEr 2S+00~~

~~26+00~~

~~27+00~~

~~26+00 IT. joHNsumr THUCtONO 29+00 30+00~~

~~31+00 LAKE SIDE AVE M loeMiani v« vpnKrral.~~

~~AMBIENT AIR "MONlTd RING LOCATIONS, TOTAL POLYNUCLEAR AROMATIC HYD'DROCAR ARSONP S (ug/tn ), FIRST ROUND-JULY, 1989. RG. 4-3 PINE STREET CANAL SITE~~

~~4-16 N illiiiig§§5Si8g§§ §§§§§§§§§§§§§§§§§ WLBUWN ITWEET 0 I I I I I I I I I I I I I I I I I SCALE (FgT) B • 100 200 300 400~~

~~LAKE CHAMPLAIN~~

~~METEOROLOGICAL DATA WIND DIR. FROM THE SOUTH/SOUTHWEST WIND SPEED 0-4 mph TEMP 45-58°F HUMIDITY 50% BAROMETER 30.5~~

~~AMBIENT Ai RFSjjONi fORIN G LOCATIONS TOTAL POLYNUCLEAR AROMATIC HYDrOROCAR ARSONF S (ug/m^, SECOND ROUND-OCT. 1989 FIG. 4-4 PINE STREET CANAL SITE~~

~~4-17 TABLE 4-5 AMBIENT AIR SEMIVOLATILE ANALYSES (ug/m') ROUND TWO~~

~~Sample I>3gatj,on,~~

~~Compound AS-005 AS-006 AS-007 t 4 Naphthalene 0.260 2-Methylnaphthalene 0.110 Acenaphthene 0.006 Fluorene 0.006 Phenanthrene 0.011 Anthracene U Fluoranthene 0.002 Pyrene 0.003~~

~~TOTALS 0.398 0.326~~

~~U undetected~~

4-18 rates. Volatile contaminants detected were four chlor;i compounds and heptene, heptane, benzene, toluene, ethyl and xylenes. The BTEXs are believed to be a result of exhaust. Several pieces of equipment were in use during the seunpling event including a drilling rig, an outboard boat motor, kerosene heaters, a generator and multiple vehicles. • This equipment was being operated approximately 100 upwind of the sampling device where the BTEXs were detected^ hlorinated compounds detected are believed to be laborato ants. Low temperatures and low vapor pressures ass with the r contaminants make it unlikely that they are a of site activity.

The semivolatile PAH scan revealed the lowest total PAH levels for all three rounds. The labofatorx failed to analyze 2 Methylnaphthalene for an unknown i^easpn^anahaehthalene was not II detected. Table 4-6 lists individualNPAftvo6n!:f§n^rations and Figure 4-5 shows locations and total PAHs. [ 4.3.3 Conclusions l! 4.3.3.1 Real Time Per^nnel Monitoring

[ The characteristics ^f/the ^feal time monitoring equipment limit the use of data^^qollected to semiquantitative purposes. It [ cannot be used to quantif^i^cohtaminants or to characterize the air quality. Most emissions wer^^ikely due to methane and appear to be rapidly dissipated since no contaminants were detected only a [ few feet fro]n_tJie source. This occupational safety and health data was collated fi

~~4-19 TABLE 4-6 AMBIENT AIR SEMIVOLATILE ANALYSES (ug/n') ROUND THREE~~

~~Samole Location~~

Compound AS-009 AS-OlO / /> AS-011 Naphthalene U /^U 2-Methylnapthalene NT " NT / /v002 Phenanthrene U 0.005 \9^004 Anthracene 0.006 0.006 0.005 Fluoranthene U U U Pyrene 0.002 0.001 0.001 Benzo(a)anthracene U 0.0003 Chrysene 0.001 /•^-^-.^^ 0.0003 < ^^^^^^^^---.^ TOTALS 0.015 W/-" 0.016 U - undetected \5 NT - not tested

~~4-20 N I I I i I i I § 8 8 8 § I 8 i i I §§§§§§S§§§§§§§§§§ lillllll~~

~~SCALE (FEET) 100 200 300 400~~

~~LAKE CHAMPLAIN~~

~~METEOROLOGICAL DAT/ WIND DIR: INITIALLY FROJ SOUTH, THEN FROM THE NORTH WIND SPEED: INITIALLY 5-10 mph WITH UP/TO 30 mph GUSTS, THEN 5 MPH WITH0U7GUSTS. TEMP10-20°F HUMIDIP<30^ BAROMETER30.3~~

~~AMBIENT^IR M~~

~~4-21 throughout the entire investigation. Site health and, records indicate workers were at no time overe contaminants as a result of improper levels of respirato: protection.~~

~~4.3.3.2 Ambient Air Monitoring~~

Ambient air monitoring indicated a clear on between Icnown "hot spots" at the site and airborne co Airbome concentrations of semivolatile compounds appear riginating 1 at the former coal gasification plant, especially surface penetrating activities. The contamination concentrations are very strongly affected by meteorological conditions. On hot, calm days, ambient air concentrations were thQ-.>greatest and on cold, gusty r days, concentrations were minimal.< E Based on the second round of sam semivolatile compounds appear to be released from the subsurf^ y drilling activities, Total semivolatile levels for roun one monitoring were [ significantly less than for round two. Round two showed a 30% increase in semivolatil ound levels after surface penetrating r activities began. Th results were approximately 90% lower than round o in total PAHs during similar [ drilling activities Missions are influenced more by meteorological conditio^ n site drilling activities. 1 The current OSHA permissible exposure limit PEL for coal tar pitch volatiles (anthracene, benzo-a-pyrene, phenanthrene, I acridine pyrene) is 0.2 mg/m' benzene-soluble fraction (8-hour ed average (TWA)). NIOSH considers coal tar produc: nogenic. The NIOSH recommended 10-hour TWA exposure coal tar products is 0.1 mg/m' (cyclohexane extractabl ) . The American Conference of Governmental

4-22 Industrial Hygienists (ACGIH) designates coal tar pitch vo as a human carcinogen with an 8-hour TWA of 0.2 mg/m' solubles). Because the more sensitive EPA sampling mettv used, for the PAH ambient air monitoring, a direct comparison between values detected and the above-mentioned standards is not appropriate. However, the values detected and the^bove standards can be compared on an order of magnitude b The most concentrated total PAH sample collected ovei^ ur period contained 0.398 ug/m', well below three magnitude difference, taking the collection time into ac Currently there are no National Ambient Air Quality Standards shed for either carcinogenic or noncarcinogenic PAHs.

~~4.4 Surface Water and Sediments~~

~~4.4.1 Surface Water Analytical~~

Organic compounds were detected ih. ei^fht (out of 20) on-site samples and in one (out of nine) off-site. C^ake Champlain) sample (Tables 4-7, 4-8). Unlike the other on-site sample locations. sample location SW-017 the former gas plant and the wetlands (referred to he"\"landing pad" in previous reports) , is not considered t entative surface water sample. This sampling point e of a twenty foot circle where no vegetation was growi^ is believed to be the location where purifier wastes were dumpe e sample was collected from a small depression in the center of circle. The water sample collected had a pH <3. This sample was collected to typify this one location and was not us^cl to characterize overall site surface water conditioils.y

~~Compoun" deyecjced at SW-017 but not at other on-site sampling points wersT pn^nari (145 ug/1), 4-methyl phenol (3 ug/1).~~

~~4-23 TABLE 4-7 ORGANIC COMPOUND CONCENTRATIONS IN ON-SITE SURFACE WA (ug/I)~~

Sample Location Compound SWOOl 003 005 006 017 019 021 022 Volatiles acetone chloroform 1.0 2-butanone 7.0 benzene 23.0 7.0 1.0 toluene 2.0 ethylbenzene 15.0 3.0 xylenes (Total) 15.0 1.0 Semivolatiles Thenol 2-methyIphenol 2.0 4-methylphenol 2,4-dimethylphenol benzoic acid acenaphthylene 4.0 naphthalene flouranthene pyrene chrysene benzo(b) fluoranthene Pesticides gamma-BHC (lindane) 0.01 heptachlor epoxide 5.0

~~^ Probable or possible human carcinogbi\ic P~~

~~4-24 TABLE 4-8 ORGANIC COMPOUND CONCENTRATIONS IN OFF-SITE SURFACE (ug/1)~~

~~Sample Location Compound SW-OOl~~

Chloroethane Acetone Carbon Disulfide 1,1-Dichloroethene 1,1-Dichloroethane 1,2-Dichloroethene (total) Chloroform 1,2-Dichloroethane 1,1,1-Trichloroethane Carbon Tetrachloride Bromodichloromethane cis-1,3-Dichloropropene Trichloroethene Dibromochloromethane 1,1,2-Trichloroethane Benzene Trans-1,3-Dichloropropene Bromoform Tetrachloroethene 1,1,2,2-aTetrachloroethane Toluene Chlorobenzene Ethylbenzene Styrene Total Xylenes

4-25 2,4-dimethylphenol (9 ug/1), benzoic acid (4 ug/1), natphtnalen^ (3 ug/1), fluoranthene (2 ug/1), pyrene (2 ug/1), chry^Mte ug/1), benzo(b)fluoranthene (1 ug/1), and a pesticide, heptachlor epoxide (5 ug/1). The phenol concentration is well below both the EPA health advisory (20,000 ug/1) and EPA ambient water criteria (AWQC) (3,500 ug/1), while there are no stanÎkrds for the methylphenols and benzoic acid. The PAHs are /abê^PA water quality criteria (0.0028 ug/1); they are believecr t^be/solubilized by the acidic conditions at this location. Since the I'AHs are at low concentrations (1-3 ug/1) and are not found ihs^tkar on-site surface water, it is not believed that the PAHs are mi^r^tlng from this location to surface waters. Other compounds detected at this location were: 2-methylphenol (8 ug/1), acetone (45 ug/1), chloroform (4 ug/1), benzene (1450 ugÔs), toluene (10 ug/1), and xylenes (98 ug/1). Acetone and 2-it(ethylpheiiDi..4iaye no criteria, chloroform is below its MCL (100 ugXl) \bui ^bsj/e EPA AWQC (.19 ug/1), toluene and xylenes are both belW PM^T^s (2000 ug/1, 10,000 ug/1) ; however, benzene is above both itsv.MCL and AWQC (5 ug/1 and .66 ug/1) \ /

At the seven oth -site locations, seven volatiles (benzene, toluene, eth xylenes, acetone, chloroform and 2-butanone), two semi-;; hylphenol and acenaphthylene) and 9 pesticides (ga )) were detected. Benzene (1 ug/1), ethylbenzene (2 nd xylenes (l ug/1) were detected near the outfall entering tft rshy area at the southem end of the site (SW-005), and benzene (7 ug/1) was detected at an outfall between the former gas plant and the Burlington Electric Company (SW-003). /<5hlorof<^ (SW-006, 1 ug/1), toluene (SW-019, 3 ug/1), and 2-methyl^henbl (Sw-019, 2 ug/1) were detected in samples from the mar^ Sirea so\itH of the canal. Acenaphthylene (4 ug/1), benzene (21 ug/QJ y el/hylbenzene (15 ug/1), and xylenes- (15 ug/1) were detecteoNin the E-W drainage ditch north of the gas plant

~~4-26 (SW-001) and 2-Butanone (7 ug/1) and toluene (2 ug/1) were sample from north of Maltex Pond (SW-022).~~

Benzene exceeded its MCL at SW-001 and SW-003 and AWQC at SW-005. Chloroform exceeded AWQC at SW-006 and acenaphthylene exceeded AWQC at location SW-001. Except for J&ei& 4 ug/1 of acenaphthylene at SW-001 (and PAHs at SW-017), r\^oX.Yie.ji PAHs were detected in on-site surface water.

~~The pesticide, gamma-BHC (lindane) was detected ats. 009 ug/1 at SW-021 in the northeast comer of the turning basin>sawQC (and Vermont water quality standards) for this pesticide are 0.06 ug/1.~~

Organics were detected in onl off-site surface water sample, SW-008, a small beach area of Lake Champlain west of the site. Seventeen chlorin c compounds (0.7 to 4 ug/1) were detected in this sam| ut not in any other surface water samples either on-site or Of these seventeen compounds, all are below federal drinking w standards; however, 1,1-dichloroethene, 1,2-dichloroethene, carbon tetrachloride. trichloroethene, and trichloroethene are above AWQCs. Acetone (10 ug/1), chl ug/1), benzene (2 ug/l), toluene (4 ug/1), ethylbenze xylenes (1 ug/l) were also detected at SW-008. compounds are below federal standards, but chlorofo benzene are above AWQCs. No PAHs were detected in any off-s surface water samples. Also, no pesticides were detected in off-site water samples, and no PCBs were detected in any surface water samples at all.

~~Tab nts pertinent information on all organic chemica surface waters and applicable water standards and crite map showing BTEX concentrations at surface water samplin s is presented in Figure 4-6.~~

~~4-27 TABLE 4-9~~

~~ORGANIC CHEMICALS DETECTED IN SURFACE UATER PINE STREET CANAL SITE, BURLINGTON, VERMONT~~

GEOMETRIC FEDERAL USEPA UATER CONTRACT RANGE OF MEAN OF LOCATION DRINKING OUALITY CRITERIA NUNBER OF REQUIRED DETECTED DETECTED OF UATER AND VERMONT CHEMICAL DETECTIONS/NO. QUANTITATION CONCEN. CONCEN. MAXIMUM STANDARDS STANDARDS CLASS Of SAMPLES LIMIT (ug/L) (ug/L> (ug/L) CONCEM. (ug/L)" (ug/L)**

VoUtUes 1 USD SU-017 S MCL 0.66 1-96 SU-017 10,000 PMCL 3-15 SU-001 700 PMCL 1,400 2-10 SU-017 2.000 PMCL 14.300 Chlorofoni 1-4 SU-018 100 NIPDUR 0.19 Acetone 10 10-4S SU-017 Chlorobenzene A SU-008 Chloroethane 10 0.7 SU-008 Carbon DUuUide 1 SU-008 1,1-Dichloroethene 3 SU-008 7 MCL 33 I 1,1-Dichloroethane 4 SU-008 L (J t,2-0Ichloroethane 3 SU-008 09 (total) 1,2-DIchIoroethane SU-008 5 MCL 0 94 1,1,1-Trlchloroethans SU-008 200 MCL 18,400 Carbon Tetrachloride SU-008 5 MCL 0 4 Iroandlchloroawthana M-00& 100 NIPOUR mt Cit-1,3-dichloropropent SU-008 100 LTHA 87 Trichloroethene SU-008 5 MCL 2 7 DI broanch t or oaw thane SU-008 1,1,2-TrIchloroethane SU-008 5 TMCL 0 6 trans-1,S-dichloropropane SU-008 L 87 BroMofona SU-008 100 NIPDUR Styrene SU 5/100 PMa 2-Butanone SU TABLE 4-9 (Continued)

~~ORGANIC CHEMICALS DETECTED IN SURFACE UATER PINE STREET CANAL SITE. BURLINGTfM, VERMONT~~

GEOMETRIC FEDERAL USEPA UATER /^\ CONTRACT RANGE OF MEAN OF LOCATION DRINKING (aUALITT CRITERIA NUMBER OF REQUIRED DETECTED DETECTED OF UATER ANO VERMONT CHEMICAL / \ DETECTIONS/NO. QUANTITATION CONCEN. CONCEN. MAXIMUM STANDARDS STANDARDS CLASS ^EMIP

Se«l-Volatitea ./• 24lethylphMfol I 2/29 10 2-8 4 SU-017 • •• / <^enBphthylene / 1/29 10 SU-001 *•• 0.0028 \ V. Phetsol.^/ / 1/29 10 145 SU-017 20.000 LTHA 3.500 \4-Methylp»w»^ 1/29 10 SU-017 • •« ... Z>4£DlmttSy I phenol 1// ^ V 10 SU-017 • *• ... Benzoic acid 1729 \ v 50 SU-017 ...... Naphthelene /l/29/ SU-017 2.000 LTHA 0.0028 Fluoranthene / \iyi \\\i \ o^° SU-017 ... 0.0028 Pyrene / ^^ ) v° SU-017 ... 0.0028 Chrysene* / AI^\_ y /IO SU-017 0.2 MCL 0.0028 Benzo(b)flueranthcnc* / /v2 9 y " SU-017 0.2 TMCL 0.0028 8enzo(a)pyr«ne* C / 1/29^ Y 10 SU-017 0.2 THCL 0.0028 4k I Petticides/PCB's Heptachlorepoxide 1/| / / 0.05 5.0 SU-017 0.2 PMCL • • • K) gamM-BHC( lindane) / 0.05 0.009 SU-021 0.2 PMCL 0.06 VO ' ^ --^

~~Probeble or possible human carcinogen PAH.~~

~~The Federal Drinlcing Uater Standards listed were selected iiosed on availabll^t^ accordhtq /o tl/e fotteuing hicrarchyt~~

MCL • Maximua Contaminant Level PMCL • Proposed Maximua Contaminant Level THCL • Tentative Maximua Contaminant Level NIPDUR • National Interim Primary Drinking Water Regulation LTHA - Longer-Tena Health Advisory (70 kg adult) L • Listed for regulation Source: U.S. EPA. Office of Drinking Water, Drinking Water Regulations end Health Advisories. April 1990.

Source for U.S. EPA Aafcient Water Quality Criteria (AUOC) and State of Vermont Water Quality Standards! StatK^Vennnt, Agency of Natural Rcsour5^s. Department of Environmental Conservation Proposed Water Quality Criteria for Proaulgation as Water Quality Standards, 1990. SW-SURFACE WATER ALL CONCENTTRATIONS IN ug/l NOTE: SW-028 LAKE CHAMPLAIN WATER INTAKE - 0 SW-029 BURUNQTON WATER INTAKE-0 Alt fiTcONCENTRATIONS IN SURFACE WATER SAMPLING LOCATIONS FIG. 4-6 PINE STREET CANAL SITE

4-30 A wide variety of inorganic chemicals were detected surface water samples collected from the Pine Street Canal Champlain. Table 4-10 lists the inorganics detected in' these samples, the range of detected concentrations, the mean of the detected concentrations and applicable federal and state drinking water standards and ambient water quality criteria

~~Barium was detected in every surface wate^ however, all of the detected concentrations were wel applicable drinking water standards and ambient water guality a (AWQC).~~

Arsenic was detected in twelve surface water samples spaced throughout the canal and Maltex Pond. All detected concentrations of arsenic were below the MCL (JS^l.ing/1) and all detected concentrations were above the AWQC ^.0(^^22 U^/UL* Arsenic was not detected in Lake Champlain.

Copper was detected in seven samples, spaced through the canal at concentrations well below drinking watiyr standards. Selenium was detected in two samples from the southern portion of the canal at concentrations well beXOw.^^drinking water standards and AWQC. Silver was detected in/on«~^urface water sample, also well below drinking water stande^d?^an^ AWQC.

Calcium, iron, maghîihn^ manganese, potassium, and sodium were detected in over 85% oK.the surface water samples. Zinc was detected in over 60% of the samples. These inorganics are essential human nutrients for which no drinking water standards or AWQC have bênpôposed. These chemicals were also detected in

~~4-31 TABLE 4-10~~

~~INORGANIC CHEMICALS DETEaED IN SURFACE UATER PINE STREET CANAL SITE, BURLINGTON, VERMONT~~

GEOMETRIC FEDERAL USEPA UATER CONTRACT RANGE OF MEAN OF LOCATION DRINKING QUALITT CRITERIA NUMBER OF REQUIRED DETECTED DETECTED OF UATER AND VERHONT CHEHICAL DETECTIONS/NO. QUANTITATION CONCEN. CONCEN. MAXIMUM STANDARDS STANDARDS aASS OF SAMPLES LIMIT (ug/L) (ug/l) (ug/L) CONCEN. (ug/D* (ug/L)'b

Inorganics 34.8-59,750 444 SU-017 L 17.7 SU-004 10/5 THCL 146 1.4-20.7 3.9 SU-019 50 NIPDUR 0.0022 7.0-852 41 SU-019 5000 PHCL 1000 Ca 5.3 SU-017 5 PMCL 10 CalciiM 17.800-343,000 42,969 SU-018 ... Chromiua 4.1-127.0 13.3 SU-017 100 PMCL (total) 50 (hex) Cobalt 39.0-85.0 57.6 SU-017 ... Copper 5.2-82.6 29.0 SU-017 1300 PMCL Iron 106-400,000 1,548 SU-017 * «• Lead 13.6-548 65.9 SU-017 5 PMCL SO Magnesium 4.260-76,900 10,870 SU-0t8 V** Manganese 5.0-30,000 272 SU-018 ... I Mercury 0.5-8.0 2.0 SU-017 2 PMCL 0.144 u Nickel 260 SU-017 100 THCL 13.4 Potassiua 1,120-24,900 SU-019 ... Selenium 1.9 SU-001 SO PHCL 10 Silver SU-018 50 NIPDUR SO Sodius SU-019 ... SW-024 2/1 TMCL Thalliua 13 Vanadiua SU-017 L Zinc SW-017 L 8W-017 200 TMCL Cyanide 200

~~The Federal Drinking Water Standards listed Mere selected based on availability, accordiitf^o the following httran~~

MCL a Maximum Contaminant Level PMCL • Proposed Maximum Contaminant Level THCL • Tentative Maximiai Contaminant Level NIPOUR • National Interim Primary Drinking Uater Regulation LTHA > Longer-Term Health Advisory (70 kg adult) L • Listed for regulation

~~Source: U.S. EPA, Office of Drinking Water, Prinking Water Regulations and Healtti Advisories. April 1990.~~

** Source for U.S. EPA Anbient Water Quality Criteria (AUOC) and State of Vermont Uater Quality Standards: State of Vermont, Agency of Natural Resoyiês^ t of Environmental Conservation Proposed Water Quality Criteria for Promulgation as Water Quality Standards, 1990. blanks, but the sample concentrations exceeded 5 time concentration detected in blanks in some instances and thus/c be disregarded due solely to blank contamination. When coittiâring the site sample results to background samples (SW-028, SW-029; Table 4-11) collected at two drinking water intakes on Lake Champlain approximately two miles from the site, irpn, manganese, and sodium concentrations appear to be significant evated. The mean concentrations of manganese and sodium wer the mean background concentration. The mean iron concentât' •m on-site surface water was 85 times the mean backgroun entration. Calcium, magnesium, potassium, and zinc mean s were all within approximately 2 times the background mean tration. It should be noted that the highest concentration of iron (400,000 ug/l) was detected in sample SW-017, which, as described in the previous discussion on organic contamina?rbs.^tis not considered a representative surface water sample.Xo-^^jSrîgnlfcLcantly elevated levels of iron (11,000 - 85,300 ug/l\ ware/no^d in the south eastern portion of the canal and the Maxtex^Pond.

Aluminum was detected in 13 samples throughout the canal and from Lake Champlain; cobalt-..was detected in only two samples (SW 017 and SW-018) and vana^Uum wks detected in only two samples (SW 017 and SW-002) . There ^are Viopi^l^sed drinking water standards or AWQC for these iiiorg2wyund samples.

Antimo detected in only 1 sample (SW-004), taken from the Malte e concentration was above proposed drinking water s ;Ut\ below AWQC. Chromium was detected in 7 samples xrom^ anal and lake. All of the detected concentratio omium were below drinking water standards and

~~4-33 TABLE 4-11 CHEMICALS DETECTED IN BACKGROUND SURFACE WATER SAMP PINE STREET CANAL SITE, BURLINGTON, VERMONT (ug/l)~~

~~Range of Detection GeometricyMean of Inorganics Concentrations Detected /CoriceDtrations~~

~~Alximinum 724 As 3.0 Ba 30.0/7.0 Ca 24,000/19,300 Cr 7.5 Fe 3,640 Pb 18.2 Mg 5,150/4,510 Mn 477/5.0 K 1,410/1,430 Na 7,930/8,570 Zn 37.4~~

~~Samples SW-028 and SW-029~~

4-34 AWQC except for sample SW-017, which was above drinking standards. Mercury was detected in 2 samples (SW-017 and The concentration of mercury was below proposed drinking water standards in sample SW-018, but above AWQC. Sample SW-017 exceeded drinking water standards and AWQC for mercury.

Thalli\im was detected in only 1 sample (SW-02 cted from off-shore Lake Champlain. The concentration o detected in this sample (8,390 ug/l) was greatly in exce proposed drinking water standards (Tentative Maximum Contamin el (MCL) - 1 ug/l) and AWQC (13 ug/l).

Nickel and cadmium were only detected in sample SW-017. The concentration of nickel was above cfrinl^ing water standards and AWQC; the concentration of cadmium v/as ^14ghtly--aljpve the drinking water standard but below the AWQC.

Lead was detected in 6 samples from, tHe canal and one from Lake Champlain. All of the sample results \^re above the proposed MCL (5 ug/l) and in some cases exceeded the AWQC (50 ug/l). The sample collected from plain (SW-007, 53 ug/l of lead) was located south of the shoreline and may have been influenced by boating arby sewer outfall. Lead was detected near the ve the canal (SW-021, 22 ug/l), near the Maltex Pond (SW^ .6 ug/l), and in the marshy area near the south-eastern end o e canal (SW-017, 548 ug/l; SW-018, 420 ug/l; SW-019, 81 ug/l). Lead was also detected in one of the background les (SW-028, 18 ug/l).

Cya: cted in seven surface samples, all located along t portion of the canal. All of the detected concentrat knide were less - than the proposed drinking water standar tative MCL - 200 ug/l) and AWQC (200 ug/l),

~~4-35 except for samples SW-017 (9,110 ug/l) and SW-018 (720 Cyanide was not detected in any blanks or background samp~~

The overall quality pf surface water in the vicinity of the site does not appear to be affected by on-site contaminant conditions. Besides the specific conditions at SW-017, frequencies of detections and concentrations for organic contamii^nts are both low. This is probeUsly due in large part/tpr tKe> relative insolubilities of the major site contaminant, ^AHi

Most of the highly elevated concentrations of iira^aj^cs were found in the samples collected from the marshy area in the southeastern portion of the canal near the old coal gasification plant (SW-017, SW-018, SW-019) and the marshy area near the Maltex Pond (SW-022, SW-004). The samples^colT&ct^d in these locations do not reflect the overall surface \(at^(r""miality7, but do present the degree of contamination present i\trWse/marshy areas.

~~4.4.2 Sediment Analytical Results~~

Organic contaminat i^ more extensive (in degree and areal extent) in site sedi an in surface water. Of the 28 sediment samples coll^t^ on-site sample collected from the Maltex Pond (SD -site samples, collected along the shore of Lake Champ D-007, 008), contained no detectable organics. Table 4-12 summ organic chemical concentrations. Because of the high concentra ion of organics (particularly PAHs) in canal sediments as compared to other sediment samples, the twelve caiMti'-Siftdiinent samples (SD-001 through SD-016) will be discussed/seP3i^ateI>

~~4-36 TABLE 4-12~~

~~ORGANIC CHEMICALS DETECTED IN SEDIMENTS PINE STREET CANAL SITE. BURLINGTON, VERMONT~~

GEOMETRIC CONTRACT RANGE OF MEAN OF GEOMETRIC MEAN LOCATION REQUIRED DETECTED DETECTED OF BACKGROUND OF CHEMICAL / \ FREQUENCr QUANTITATION CONCEN. CONCEN. CONCEN. MAXIMUM CLASS CHEHTCALX,^ OF DETECTION LIMIT (ug/kg) (ug/kg) (ug/kg)) (ug/kg) CONCEN.

Volatiles /„/\\ 12/28 10-1250 11-30,000 372 SO-020 / Tot^ XyteneJ 10/28 5-625 375-270,000 12.878 C E^ylbenzeny / 10/28 5-6?5 305-210.000 14,815 B / / Menene / 1 7/28 5-625 111-240,000 10.556 * \ Hfev 5-625 1,900 • 2-Butanone //28/v . \10-1250 33 A Chlorobenzene /MZy \ \5-625 14.000 SO-014 780 SO-011 Tetrachloroethene / '' ^ ) V**"' Pesticides/PCBs Dieldrin / /l>28 ^^"-^ 16^-240 62 SO-009 Endrin / / 1/28\ ^-.^.0-21,0 66 SO-009 itw 4,4<-00T >v/ 2/28/ ) 16.0-240 1.700-2,100 1.889 SO-014 1 4,4«-DOD 1/2»^ / 16.0-240 1,000 SD-015 vl Semi-Volatiles Naphthalene 11/28s^/ 10-1250 11,000-2.7JI^S 136.774 110 SD-014 2-Hethylnaphthalene 11/28 10-1250 5,200;?d5M S 115,580 130 SO-014 Acenaphthylene 9/28 10-1250 9,000;^,00a / 21.502 152 SD-014 Acenaphthene 11/28 10-1250 40.0D<^930J)flff / 108.677 SD-014 Dibenzofuran 11/28 10-1250 ^^oo-iAoTogft ;( 14,069 SO-014 / 2.4-Dinitrotoluene 3/28 10-1250 ./ 7.100-^0(10 / 10,588 SO-013 flourcne 11/28 10-1250 ^S2^<t)0 / 65,705 SO-014 4-Nitrophenol 1/28 50-6250 ^200/ SO-014 Phenanthrene 15/28 10-1250 1,700-I.6M / 74,960 /v 177 SO-014 Anthracene 15/28 10-1250 220-51d,00(y 27,293 SO-014 39,978 / \w SO-014 Fluoranthene • 15/28 10-1250 2,50O-43O:«QP / /v'^ Pyrene 15/28 10-1250 2.800-650,000 57,587 V SO-014 Benzo(a}anthracene* 16/28 10-1250 270-200,000 14,729 / /NM^ / SO-014 Chrysene* 16/28 10-1250 330-160,000 14,516 / / ^^'C "« ^" ^ SO-014 BiB(2-ethylhexyl) 11/28 10-1250 320-160,000 3,129/ /\ > SO-014 phthalate / 8enzo(b)fluoranthene* 13/28 10-1250 1,000-78,000 10,890s y / N27Z3 SO-014 Benzo(k)fluoranthene* 12/28 10-1250 660-97,000 11,484 273 SO-014 Benzo(a)pyrene* 15/28 10-1250 250-150,000 10,855 157 SD-014 lndeno(1,2,3-cd)pyrene* 15/28 10-1250 490-58,000 7,414 130 SO-014 D{benz(a,h)anthracene* 6/28 10-1250 270-5,300 3,935 SD-015 Benzo(g,h,i)perylene 14/28 10-1250 260-64,000 7,964 161 SO-014 Dimethylphthalate 1/28 10-1250 3,100 * Besides the canal sediment samples, thirteen sediment wer& collected in on-site drainage and depressions an sediment samples were collected off-site along the shore of Lake Champlain. Seven volatile organics were detected in these samples and only three of them were detected more than once. Methylene chloride was detected four times: at a storm/sewer/'onfall at the southern end of the site, SD-005 (220 ug/kg); at^ drai*iage ditch just north of the previous (SD-005) location, SJS-0^9 /296 ug/kg); at the "landing pad" west of the former gas pla: (1300 u g/1); and in the marshy area between the wetlands former gas plant, SD-020 (660 ug/kg). Acetone was detected times; however, only two samples had concentrations above levels established by blank contamination. A sediment sample from the east-west drainage ditch north of thfS~~-94s plant (SD-001) had a concentration of 2000 ug/kg. Sample Nloc>ation5©-<120, downgradient from the drainage ditch, had an acet^e\c(nicentration of 30,000 ug/kg. Benzene was detected twice: xn the east-west drainage ditch (SD-001) at 160 ug/kg; and at a s^rm drain/sewer outfall between the former gas plant and the BurliVjgton Electric Company (SD-003) at 2800 ug/kg. Ethylbenzene and xylenes were both detected once at locati ^001 at 350 ug/kg and 390 ug/kg, respectively. Toluene d once at the drainage ditch at the south of the si 1 ug/kg and 2-butanone was detected at 38 ug/kg ea north of Maltex Pond (SD 022), No yoiatile contami was detected in the three off-site samples, SD-007, 008, and

Semivolatiles were detected in four of the 16 non-canal sediment samples.^^s(2-ethylhexyl)phthalate was the only non-PAH semivolatile^dete^eoN, (six times) but no concentration values were above th'ose <^terminedj by blank contamination. The drainage ditch in the sotrt^erlv^nd^ of the site (SD-019) had a total PAH concentration^^^la/soo ug/kg. SD-020, between the wetlands and

4-38 former gas plant, had a total PAH concentration of 22,700 u Location SD-030 near the middle of the site had a tot/l concentration of 850 ug/kg. This location was near a grave that provided access to the interior of the site. Sample SD-028, collected along the shore of Lake Champlain approximately a mile north of the site, was the only off-site sample /^at detected semivolatiles. This sample had a total PAH concent^^on of 13,900 ug/kg.

Two pesticides were detected at one locatioh^ in\{ion-canal sediments. Location SO-009 at the entrance of the ca)^l yto Lake Champlain had 62 ug/kg of Dieldrin and 66 ug/kg of Endrin. No PCBs were detected in non-canal sediments.

Twelve sediment samples were collected six locations in the Pine Street Canal. At each loc i^ny'i :icial sediment sample (0-2 feet) and a deeper (2-6 f -tV-imple was collected. Scimple SD-011 was collected in the midd the turning basin. SD-012 through SD-015 were collected down length of the canal and SD-016 was collected at the southern end of the canal in the wetlands. The "S" suffix/'fos^sample numbers denotes the shallow sample, the "D" suffix ^n^yb^s Y^he deeper sample.

The major volati amination in the canal is due to BTEXs. Three othe tiles were detected once each: tetrachloroethane, 780 ug/]^ D-OOlD) in the turning basin; methylene chloride, 24,000 ug/kg (SD-014S) in the middle of the canal; and chlorobenzene, 14,000 ug/kg (SD-014D). Acetone was detected tw the turning basin at 6300 ug/kg (SD-OOID); and at the soyx: f the canal at 5000 ug/kg (SD-016S). BTEXs were no ither sample collected in the turning basin (SD-OOIS, deeper sample for SD-012 through SD-015 exhibited values than the shallow sample. This trend

4-39 is reversed in sample SD-016 where the shallower sample greater BTEX value. The general trend was for the shallow to detect only ethylbenzene and/or xylenes and for the creeper samples to also detect benzene and toluene. SD-016 detected all forms of BTEXs in both samples. There was also a trend for BTEX values to increase from the turning basin to the $iouth in both shallow samples (0 ug/kg, SD-DllS to 698,700 ug/kj D-016S) and deeper samples (0 ug/kg, SD-OllD to 431,000 ug/kj ). The largest concentration for benzene was 47,000 ug/ toluene, 80,000 ug/kg, both in SD-015D. The largest cd ^ation for ethylbenzene (300,000 ug/kg) and xylenes (350,000 ug/ e both in SD-016S. Table 4-13 presents the total BTEX values ^or each sample and Figures 4-7 and 4-8 are BTEX concentration maps for the shallow and deep sediments.

For semivolatile analyses, all t pies contained complete or almost complete suites PAHs analyzed for. Dibenzofuran was also detected in eve ample. There were infrequent detects of four other semivola s: 4-chloroaniline (5900 ug/kg, SD-014S); 4-nitrophenol (5200 ug/kg, SD-014S); 2,4 dinitrotoluene (7100 ug/k D-012D, 19,000 mg/kg - SD-013S, and 8800 mg/kg - SD-015S) ; a ethylhexyl)phthalate (7300 ug/kg SD-013D, 160,000 ug/kg 8300 ug/kg - SD-014S). Table 4-14 presents total each sample. As with BTEX concentrations, there is d of increasing PAH concentrations to the southern end of the an>il. However, there is no trend between PAH concentrations and deep or shallow samples. This may be due to the relative insolubility of PAHs compared to VOCs. Figures 4-9 0 are Total PAH concentration contour maps for both shall, samples. As can be seen on Table 4-14, total PAH val ent value (i.e., 1% total PAH at SD-014) towards nd of the canal. Figures 4-11 and 4-12 are concentratioi^ maps for total carcinogenic PAHs. The

~~4-40 TABLE 4-13 TOTAL BTEX CONCENTRATIONS FOR CANAL SEDIMENTS~~

~~Concentrations fua/kal Sample Shallow Deep~~

~~SD-001 0 SD-012 3300 SD-013 7400 SD-014 19,400 SD-015 10,300 SD-016 698,700~~

~~4-41 4-42 ^ N IJ I i i ! I g 2 I 8 S § 8 8 I § (T\ SSSS§SSS§SSSSSS8§ NLBUIMVmCET illlil~~

~~SCALE (FEET) 100 200 300 400~~

~~LAKE CHAMPLMN~~

~~(A a CONCENTRATIONS IN PPB) Hloutam m9 apfxmtrm~~

~~DEEPER CANAL SEDIMENTS FIG. 4-8 PINE STREET CANAL SITE~~

~~4-43 TABLE 4-14 TOTAL PAH CONCENTRATIONS FOR CANAL SEDIMENT SAMPLES~~

~~Concentrations fua/ka> Sample Shallow / v Deep~~

~~4-44 N liliiiisssssis §§§§§§§§§§§§§§ I I I I I I I I I I I I I r~~

~~SCALE(FEET)~~

~~4-45 -N I I I i I ! I 8 8 § 8 8 § 8 8 § § (T\ SSSSSS§§§§§§SSSSS WLaUWN STWEET~~

~~SCALE (FEET)~~

~~100 200 300 400~~

~~LAKE CHAMPLAIN~~

~~(A a CONCENTRATIONS IN PPB)~~

~~TOTAL PAH'S IN DEEPER CANAL SEDIMENTS FIG. 4-10 PINE STREET CANAL SITE~~

~~4-46 ii!iili88l8S§88§8 §§§§§§§§§§§§§§§§§ I I I I I I I I I I I I I I I I I SCALE (FgT) 100 200 300 400~~

~~(ALL CONCENTRATIONS IN PPB) x^V/g CARCINOGENIGfeN|0C PAH'l S IN SURFACE SOILS/SEDIMENTS FIG. 4-11 PINE STREET CANAL SITE~~

~~4-47 §iSSI8S888§8 mi §§§§§§§§§§§§ MLBU)*! STKET i i I I I I I I I I I I~~

~~(ALL CONCENTRATIONS IN PPB)~~

~~CARCINOGE=Nt^AHN ' S IN DEEPER CANAL SEDIMENTS FIG. 4-12 PINE STREET CANAL SITE~~

~~4-48 contour outlines are similar to total PAH contours; howevei\, because carcinogenic PAHs are only seven of the sevente^/^X^s \ ^ analyzed for, the total concentrations are lower. \.^^ ^ s~~

Two pesticides were detected in two canal sediment samples. The pesticide 4,4*-DDT was detected at 2100 ug/kg in SD-014S and 1700 ug/kg in sample SD-015D. Sample SD-015D also /letected 1000 ug/kg 4,4'-DDD. No PCBs were detected in any sefliment/s^ples.

While there is both volatile and semlvoo^trs^e organic contamination in almost all sediment samples on-site, xhegreatest concentrations of all organics is in the sediments of the canal. There is a noticeable decrease in contaminant concentrations in all compounds from the south to the north. Historic air photographs of the former gas plant indicate two ^ t of the gas plant with drainage patterns that indicate hf fluids flowed from these outfalls into the wetlands, quite possible that one of these outfalls was from the gas t oil/tar separator. Water containing from five to seven per emulsified process wastes are not uncommon in this type of operation. The process is then set up for the canal be acting as a settling pond; as the emulsified tars/oils mo down the canal, they slowly settle out of the water and m. incohesive canal sediments. This scenario would rge volume of PAHs in canal sediments. It is possi)^ t the higher concentrations of PAHs near the southern barge s e due to the settling of large quantities of emulsified wastes with high specific gravities. It is estimated that there are 30,000 cubic yards of unconsolidated sediments in-'tHe'^sanal complex. The PAHs detected in the off-site sediment sampIe"^-028, a mile north of the site, are unexplained but are/no4 belieVeoi to be associated with Pine Street Canal sediments^

4-49 As would be expected in any sediment samples, an ext eunount of inorganics were detected in the sediment sample Pine Street Canal Site. Table 4-15 lists all the inorganics detected, the range and geometric mean of the detected concentrations, and the geometric mean of the eight background surface soil samples collected within one-half mil^of the site. The concentrations detected in the sediment samples will be compared to the site specific background soil saffipl^s^ana regional background concentrations (Shacklette and Boeri^geny 3^84) listed in Table 6.1.1.

The geometric mean concentrations of aluminum, arsenic, bariiom, beryllium, chromium, cobalt, copper, iron, lead, manganese, and vanadium were all found to be belj3W.2 times the geometric mean of the site specific background soi would generally indicate that these inorganics are n ed contaminants. However, the maximum detected concentra f aluminxim, chromium, cobalt, copper, iron and lead were all a the maximum regional concentrations, indicating that certain as may have elevated concentrations of these inorganics. The geometric mean concentrations of lead, and chromium were also above maximum regional value

Lead concentratil>ns ^r^/higfte^t in samples SD-014 and SD-015 (458 - 609 mg/kg), which ^were^'^cated in the south-central portion of the canal. These concent^a;cions are well above the regional background maximum (20 mg/kg) and the site specific background maximum (i59 mg/kg). Elevated lead concentrations were noted in samples SD-?d'05/~S!>^16, SD-017 (262, 263, 304 mg/kg) located in the southem/pordon\Df\:he canal; SD-012 and SD-013 (244 mg/kg, 236 mg/kg),

~~4-50 TABLE 4-15~~

~~INORGANIC CHEMICALS DETEaED IN SEDIMENTS PINE STREET CANAL SITE. BURLINGTON, VERMONT~~

GEOMETRIC CONTRACT RANGE OF MEAN OF GEOMETRIC MEAN LOCATION REQUIRED DETECTED DETECTED OF BACKGROUND OF CHEMICAL FREQUENCY QUANTITATION CONCEN. CONCEN. CONCEN. MAXIMUM CLASS OF DETECTION LIMIT (mg/kg) (mg/kg) (mg/kg) (mg/kg) CONCEN.

Inorganics 28/28 40 1.150-19,500 8,780 6,330 SO-017 3/28 12 2.3-9.0 7.4 SO-006 27/28 2 1.80-15.10 6.80 8.5 SO-017 28/28 40 7.3-195.0 68.9 46.7 SO-015 6/28 1 0.11-1.00 0.22 0.46 SO-006 8/28 1 0.98-8.3 2.76 SO-014 28AaK« 1,000 652-197.000 8,096 2,997 SO-004 Chromium 28/28 " V 2 5.1-163.0 30.2 15,36 SO-017 Cobalt /7/28.S ^ v 10 2.0-21.7 10.2 6.4 SO-020 Copper /rt m \ \ 5 5.5-275 41.0 29.9 SO-014 Iron / 28/28 N \ 20 6,720-47.800 25,108 13,417 SO-014 Lead / 28/»\ ^ 1 ^ 6.1-609 98.3 60.0 SO-014 Magnesium / /tt^ m ^-^ / 1,000 1.530-11,500 5,950 2,326 SO-0160 Hanganese ' / 28/av , ^ 3 91.2-1,030 362 300 SO-018 Mercury \ y i6/2y ) "-^ 0.20-2.3 0.76 SO-017 Nickel 28/26 / 8 5.3-56.0 23.3 13.7 SO-014 Potassiua 28/28 / 1,000 109-2,590 1,153 490 SO-017 Selenim 13/38/ 1 0.28-9;^. 2.2 0.94 SO-017 I Silver 8/28^^ 2 17.0;*^4 ^s 13.7 SO-014 Ul H Sodium 20/28 1,000 ipzil.6W / 468 50.4 SO-006 Vanadium 28/28 10 y(>.Q-y(h 1' 20.3 17.2 SO-014 Zinc 28/28 4 y Z rz.yS.^ti I 171 65.6 SD-006 Cyanide 13/28 10 > -^ ^-5^7 / 12.9 SO-015 Iron concentrations were also highest in samples SD-0 SD-015 (46,100 mg/kg to 47,800 mg/kg). These concentrat Eibove the regional background maximum (3,000 mg/kg) and the s specific background maximum (17,000 mg/kg). Elevated levels of iron were also noted in SD-012 (39,200 mg/kg) and SD-013 (39,900 mg/kg), located in the central portion of the canal;/SD-017 and SD 001 (42,800 and 43,200 mg/kg), located in the southeastern portion of the canal; and SD-011 (37,100 mg/kg), locatea xn tne/northem portion of the canal.

Chromium concentrations were also elevated in sadtple^ SD-014 and SD-0015 (81.6 to 138 mg/kg), but the highest value was noted in sample SD-017 (163 mg/kg). These concentrations are above the regional background maximum (2 mg/)cg:i and the site specific background maximum (36.5 mg/kg). A^with iSad...,^nd iron, elevated concentrations of chromium were netted Niriy^saBi^^s SD-011 (87.7 mg/kg), SD-012 (79.8), and SD-013 (64.60^, which are spaced through the north and central portions of the canalN.

Cobalt, copper, and aluminum concentrations follow the same general pattern as lead,/j:rein, and chromivim. Elevated levels, cibove regional and site/sp^if^c background maximums, were noted in the sediment sampX©^talcen dibex:tly from the canal (SD-011 through SD-015) and instheNtrea soiitheast of the canal (SD-017, SD 001) near the old coal g^tsifib^ion plant.

The geometric mean of the detected concentrations of magnesium, mercury, nickel, antimony, potassium, and sodium were all above the geometric mean of the site specific background tf^tions. However, the maximum detected concent se inorganics were less than the maximum regional oncentrations, and for this reaison these inorganics we Considered to be site-related contaminants.

4-52 The geometric mean of zinc (171 mg/kg) and calcium ^9/Hg) detected concentrations were above 2 times the g mean of the site-specific background concentrations (65.6 and 2,997 mg/kg respectively). The maximum detected concentrations of zinc (1030 mg/kg) and calcium (197,000 mg/kg) were also above the maximum regional background concentrations (45 an6K2,800 mg/kg respectively). Concentrations of zinc and cal elevated throughout the site. It should be noted that thj nics are essential human nutrients which are not general to humans. except in very high doses.

~~Cadmium, silver, and cyanide were detected in on-site samples and were not detected in site-specific or regional background samples, which indicates that these a?7»-.si.te-related contaminants.~~

Concentrations of cadmium were hr pies SD-014 (8.3 mg/kg) and SD-015 (3.9 mg/kg), as many of the other inorganics. Cadmium was detected in eig! her sediment samples spaced throughout the site at levels of 1 2.2 mg/kg.

Concentrations of si were also highest in samples SD-014 (96.4 mg/kg) and SD-015 g) . Silver was also detected in sample SD-013 at 23.6 at 17 mg/kg, and in 5 other samples spaced throug: a concentration of 2 mg/kg.

Concentrations of cyanioejwere again highest in samples SD 014 (44.9 mg/kg) and SD-015 (73.7 mg/kg). Cyanide was detected in sample SD-bl6 (32.3 mg/kg) located in the southern portion of the canal and iiaTseven^her sample locations at concentrations ranging from 2.0 mg/^cg t^\l3\L mg/kg.

~~Inorg nants appear to have accumulated in the canal sediments to est degree directly west and northwest of the~~

~~4-53 old coal gasification plant. This would correlate with the geheraK. runoff pattern of the site and the expected transport: df \. contaminants generated at the old coal gasification plant. x. ^~~

~~4.5 Soils Investigation Results~~

The soil gas survey, geophysical surveys, atic and selected soils investigation, the soil boring a ing well installation program and results from previous ations can all be synthesized to create a complete picture o chemical contamination of soils at the site. Soil samplesXc^lected throughout the site and surrounding area are divided into groups depending upon the rationale for which the sample was collected. These groups are: systematic surf|rce..^oils; selected surface soils; background soils; and subsuri

~~4.5.1 Background Soil Samples~~

Eight background soil samples were corQ/ected within one half mile of the site. Organic chemicals detected in off-site background soil samples ar€'"pt^sented in Table 4-16, and inorganic chemicals are presented/in^'^^34e-^-17.

Chloroform, a common lat/con-raminant, was the only volatile organic detected in backgrbrnidNiDils (2 ug/kg at both BS-OOl, 002). Sixteen semivolatiles were debased in background soils, 14 of them being PAHs. The two non-PAH semivolatiles detected were: benzoic acid detected five times, ranging from 79 to 410 ug/kg; and butylbenzyljmthalate detected once at a concentration of 66 ug/kg. The 14 PMs/dete^tea\ off-site are the same as detected on-site, althoughCno^individpa^ PAH had a concentration greater than 1200 ug/kg off-kite.

~~4-54 TABLE 4-16~~

~~ORGANIC CHEMICALS DETEaED IM BAOCGROUND SOIL PINE STREET CANAL SITE. BURLINGTON. VERMONT~~

~~NUMBER OF RANGE OF DETECTED CHEMICAL DETECTIONS/NO. CONCENTRATIONS LOCATION OF GEOMETRIC MEAN FOR CLASS OF SAMPLES (ug/K) MAXIMUM CONCENTRATIONS DETECTED CONCENTRATIONS~~

~~Volatiles 2/8 2 - 2 BS-001 BE-002~~

Semi-Volatiles ^Benzoic/Acid BS-002 169 Kalei BS-002 ^Methy^n^tlialena BS-002 Acensptithylene BS-005 152 Phenanthrene BS-005 177 Anthracene BS-005 89 Fluoranthene BS-005 300 Pyrene BS-005 302 Butylbenzylphthalate BS-007 Benzo(a)Anthracene* BS-005 152 Chrysene* BS-005 218 Benzo(b)Fluoranthene* BS-005 273 I BS-005 Ul Benzo(k)Fluoranthene* 273 Ul Benzol a)Pyrene* BS-005 157 Indenod,2,3-cd)Pyrene* BS-005 130 Benzo(g,h,i)Perylene BS-005 161

~~Pesticides/PCBs 4.41-ODE BS-005 429 4,4 -DDT BS-005 243~~

~~Probable or possible husan carcinogen PAH. TABLE 4-17~~

~~INORGANIC CHEMICALS DETECTED IN BACKGROUND SOIL PINE STREET CANAL SITE. BURLINGTON, VERMONT~~

~~NUMBER OF RANGE OF DETECTED CHEMICAL DETECTIONS/NO. COHCENTRATIONS LOCATION OF GEOMETRIC MEAN FOR CLASS OF SAMPLES (ug/K) MAXIMUM CONCENTRATIONS DETECTED CONCENTRATIONS~~

Inorganics 8/8 3250 - 9790 BS-008 6330 7/8 4 - 25 BS-002 8.5 8/8 27-81 BS-001 46.7 2/8 0.40 - 0.60 BS-002 .46 8/8 1310 - 7010 BS-001 2997 8/8 9 - 36 BS-002 15.4 /V 8/8 3 - 9 BS-001 6.4 Copper \. 6/8 16.2 - 70.9 BS-002 29.9 Iron ^. \ 8/8 6960 - 17000 BS-008 13417 Lead 24.1 - 159.0 BS-005 60.0 Magnesius A \ N8/8 606 - 5440 BS-001 2326 Manganese / X v« 55.3 - 531.0 BS-004 300 Nickel .\ ^-)^ 3/>88 8.9 - 19.4 BS-001 13.7 Potassiua \ , / 7 269 • 956 BS-001 490 Selenium ) \ 7 0.6 - 3.7 BS-002 0.94 Sodiua 27.2 - 550.0 BS-002 50.4 I / / 7 Thalliua ( / ^ 0.50 BS-002 Ul Vanadium \l • 13«6 - 20.7 BS-008 17.2 Zinc ^ 8 Jtf.l >M38.0 BS-005 65.6 No PCBs were detected in off-site soils; however, pesticides were found. 4,4'-DDE was detected three times maximum concentration of 4400 ug/kg. 4,4'-DDT was also detected four times with a maximum concentration of 5900 ug/kg. Inorganic data was compared to published background soil data (Shacklette and Boeringen, Table 6-1). Of the nineteen inorganic me^SLLs detected, six (arsenic, chromium, selenium, copper, lead and/zi/u;) /Jiad higher concentrations than published data.

~~4.5.2 Selected Soil Samples~~

~~Six surface soil samples were collected from various parts of the site to be analyzed for dioxin/furans. No dioxin/furans were detected at any concentrations in anyr«f,^he selected samples.~~

~~4.5.3 Systematic Surface Soil Sam;~~

~~Twenty-nine surface soil (0-6" depthjv samples were collected, using a 200 x 200 foot grid, over the entir^site. This sampling provides data for an unbiased characterization of surface soils.~~

~~Table 4-18 provide of chemicals detected, frequency of detection and othe~~

~~4.5.3.1 Volatile Organi~~

Six volatile organics were detected in on site surface soils. While the isoil gas survey detected BTEX vapors from two to three feet below yCne su^^ce, no BTEX's were detected in surface soils (Figure 4

~~4-57 TABLE 4-18~~

~~CHEMICALS DETEaED IN SURFACE SOILS PINE STREET CANAL SITE. BURLINGTON, VERMONT~~

GEOMETRIC GEOMETRIC CONTRACT RANGE OF MEAN OF MEAN OF LOCATION NUMBER REQUIRED DETECTED DETECTED BACKGROUND OF CHEMICAL OF DETECTIONS/ QUANTITATION CONCEN. CONCEN. CONCEN. MAXIMUM CLASS NO. OF SANPLES LIMIT (ug/kg) (ug/kg) (ug/kg) (ug/kg) CONCEN.

~~Volatiles 5 1-13 SS-005 10 2-53 SS-006 5 1-5 SS-026 10 7-10 ss-ooa Trichloroethene 5 3 SS-011 Chloroform~~

Semi-Volatiles Naphthalene 79-6,400 SS-031 Acenaphthylene 36-5.200 SS-031 Acenaphthene 110-220 SS-005 Dibenzofuran 140-560 SS-018 Fluorene 120-220 SS-005 Phenanthrene 51-6.700 SS-031 46-2.800 SS-031 I Anthracene 11 Ul Fluoranthene 23/29 3.000 SS-018 09 Pyrene 23/29 6.000 SS-031 Benzo(a)anthracene* 19/29 6.000 SS-031 Chrysene* 21/29 •6.800 SS-031 Benzo(b)fluoranthene* 22/29 -13,000 SS-031 Benzo(k)fIuoranthene* 12/29 4,400 SS-018 Benzo(a)pyrene* 23/29 42-6.200 SS-018 lndeno(1,2,3-cd)pyrene* 20/29 40-3,400 SS-031 Dibenz(a,h)anthracene* 6/29 62-1,400 SS-005 Benzo(g,h,i)perylene 17/29 36-3,500 SS-031 Benzyl alcohol 1/29 730 SS-015 SS-015 Nitrobenzene 1/29 730 SS-018 2-Hethylnaphthalene 6/29 37-3,100 SS-020 N-nitrosodiphenylamine 1/29 780 SS-018 Di-n-butylphthalatc 1/29 500 SS-022 Bis(2-ethylhexyl)phthalate 11/29 49-1,100 SS-024 Benzoic acid 2/29 35-130 SS-033 2,4-Dini trotoluene 1/29 39 Butylbenzylphthalate Pesticides/PCBs 4,4'-0OT 1/29 16.0 53 SS-015 alpha-BHC 1/29 8.0 320 SS-030 4,4'-0DE

~~Probable or possible hunan carcinogen PAH. TABLE 4-18 (Continued)~~

~~CHEMICALS DETECTED IN SURFACE SOIL PINE STREET CANAL SITE. BURLINGTON. VERMONT~~

• GEOMETRIC GEOMETRIC / / \ \ CONTRACT RANGE OF MEAN OF MEAN OF LOCATION / /N \ NUMBER REQUIRED DETECTED DETECTED BACKGROUND OF CHEHICAL / / / / 1 11 OF DETECTIONS/ QUANTITATION CONCEN. CONCEN. CONCEN. MAXIMUM CLASS / •• ytHEMICAL / / NO. OF SAMPLES LIMIT (mg/kg) (mg/kg) (mg/kg)) (mg/kg) CONCEN.

Inorganics ^vAluainua^/ 29/29 40 3,060-16.900 6,515 6,330 SS-008 Aht4ei8ny 11/M \ 12 5.6-38.5 10.7 SS-005 Arsenic My29 ^\ 2 1.20-11.90 4.28 8.5 SS-014 Bariun /9/2«^ \ 40 7.2-451 38.2 46.7 SS-018 Berylliua /l5/ / ^N \ ^ 0.10-0.81 0.32 0.46 SS-020 Cadmiua / 16/29 ; ) ^ 0.28-4.1 0.57 SS-022 Calciua / ;i^/29\ _ y / 1000 11,290-254.000 5,058 2,997 SS-007 Chromiua / /29>29 y 2 7.10-43.00 15.60 15.36 SS-011 Cobalt <^ / 20/29) 1r- ^ 10 4.5-18.9 7.86 6.4 SS-014 Copper \ ^ 25/2*/ 5 7.2-63.2 19.4 29.9 SS-018 I Iron 29/2^ /' 20 8,280-35,600 16.621 13,417 SS-008 Ul Lead 29i ^ / 1 3.5-873 33.8 60.0 SS-018 Magnesium 29/Xj 1,000 /''^M-H.OOO 3.968 2.326 SS-005 Hanganese 29/29 3 y y 1747b-789.0 323 300 SS-008 Mercury 10/29 yZ . 0/08-9.4 0.25 SS-032 Nickel 29/29 °-^• / > y ] 9/0-236.1 19.5 13.7 SS-032 1 Potassiua 29/29 1,MP ^ y / f 0-1.820 686 490 SS-008 Seleniua 6/29 <^ ^ \ / /0.12-1.3 0.49 0.94 SS-011 Silver 2/29 V ^ / 1.10-342 19.4 SS-032 Sodium 29/29 1,00\i/0 ^ N. /l.76-1,060 •252 50.4 SS-018 Thalliua 5/29 2 / / 0.08-7.7 0.23 /v 0.49 SS-032 Vanadium 29/29 10 / / 5.6-31.3 12.9/ \ . 17.2 SS-011 Zinc 29/29 4 X/ 9.0-722 a.ji /v^* SS-020 Cyanide 6/29 10 0.71-1.86 0/95 / \ \ SS-029 Acetone, which was detected in six samples, was eli from consideration because the highest concentration detec€ ug/kg) was below the concentration detected in blank samples for soil (58 ug/kg).

Methylene chloride was detected six times} SS-001 (1.0 ug/kg), SS-002 (2.0 ug/kg), SS-003 (9.0 ug/kg), S 0 ug/kg) and SS-006 (2.00 ug/kg) all in the field area i le of the site; and SS-027 (5.0 ug/kg), at the north end of te.

Carbon disulfide was detected five times: SS-017 (3.0 ug/kg), SS-018 (2.0 ug/kg), at the north end of site; SS-026 (5.0 ug/kg), west part of site; SS-031 (1.0 ug/kg) between the former gas plant and Burlington Electric Department; ^nd sS^="&3.3^(5.0 ug/kg) at the former gas plant.

~~2-butanone was detected twice: SS- (7.0 ug/kg), and SS 019 (10 ug/kg), both at the former fuel ^ge area.~~

While the soil gas s did detect tentatively identified concentrations of trichl a\e in the wetlands just north of GE, trichloroethene was on ce in surface soil samples at location SS-029 (6.0 a workshop of the Burlington Electric Department.

~~These results indicate that there is no extensive volatile contamination of surface soils.~~

~~4.5.3.2 il^ Organic Analyses~~

~~Twen latiles were detected in surface soils, with PAH's occurri the greatest frequency. Eliminating bis(2~~

4-60 ethylhexyl)phthalate because of blank contamination, seven nc^ semivolatiles were detected, all in three samples or less, north end of the site, dibenzofuran was detected at SS-0 ug/kg) and SS-019 (140 ug/kg); at SS-015, benzyl alcohol was detected at 130 ug/kg and nitrobenzene was found at 730 ug/kg; and at SS-018 di-n-butylphthalate was detected at 500 uji/kg

Dibenzofuran was also detected in the midd}^ SS-005 (170 ug/kg). N-nitrosodiphenylamine w an unpaved parking lot (SS-020) near the Bur Department at 780 ug/kg. At SS-033, in the gas pla dinitrotoluene was detected at 39 ug/kg and benzoic acid at 35 ug/kg. Benzoic acid was also detected at SS-024 (130 ug/kg) a grassy area at the western edge of the site. Results suggest that non-PAH semivolatile concentrat iong--

PAH concentrations were detected irw 24C of 29 samples. Four to six ring PAH's were detected more frequeirtly (approximately 20 out of 29 samples) than 2 to 3 ring PAH's (approximately 5 out of 29 samples). Figure 4-13 total PAH concentration contour map. As can be seen from re, total PAH concentrations of greater than 1,000 ug/ of the site soil surface. The highest concentratio 6,900 ug/kg) in the gas plant area. It should be note total PAH concentrations for soils, while present over most of s^te at concentrations greater than 1,000 ug/kg, are two orders magnitude lower than total PAH concentrations for sediments in the canal.

~~Figu a concentration contour map of total carcino' e 1,000 ug/kg contour for carcinogenic PAH's covers a and more closely follows the shape of the wetlands, ca urning basin.~~

~~4-61 N 8 § 8 8 8 J 8 8 8 8 8 18 i s i i i i s s § s § § § I I I I I. I I I~~

~~(ALL CONCENTRATIONS IN PPB)~~

~~TOTAL PAH'S IN SURFACE SOILS/SEDIMENTS RG. 4-13 PINE STREET CANAL SITE~~

~~4-62 N iiliiil88§SS§888i (T\ SSSSSSSSSS88S§S§S II i I I I I I I I I I I I. I I I~~

~~SCALE (FEET)~~

4-63 No PCB's and only two pesticides were detected in surfacze samples. 4,4-'DDT was detected at SS-015, just east of the Wming basin (53 ug/kg). Behind a Burlington Electric workshop (SS-029), alpha-BHC was detected at 320 ug/kg.

~~4.5.3.3 Summary~~

~~Volatile contamination in the surface soi Street is minimal. BTEX's were not detected in any surf a samples. probably because of their high volatility.~~

PAH contamination is more widespread, covering most of the site with total PAH concentrations greater than 1,000 ug/kg. Since this entire area is prone to flood possible that this mechanism is responsible for the sp •s^ By comparing Figures 4-13 and 4-14, it can be see n Figure 4-14, the carcinogenic PAH (mostly less soluble avier 4-6 ring PAHs) concentrations are highest in the low ly reas centered around the canal. When the relatively lighter 2-3 ring PAH's are added to the total PAH concentrations, the 1,000 ug/kg contour line covers those areas most/feu^a^ect to flooding (Section 3.3, Figure 3-2) .

~~4.5.3.4 Inorganic Anal~~

An extensive number of inol^anics were detected in the surface soil samples. The concentrations of inorganics detected on-site were compar;ed to<^^ the site specific background surface soil concentrati^OT?^ and TO regional background soil concentrations (Table 6^1-4.) to determine if on-site concentrations are above naturallyNjccTirringy levels.

4-64 The geometric mean concentrations of barium, beryl]^ manganese, nickel, selenium, arsenic, copper, potassium, sodi; vanadium in the on-site surface soil samples were all.less times the geometric mean concentration of the site specific background samples. Also, the maximum detected concentrations of these inorganics on-site were less than the maximum regional background concentrations and/or the maximum >^te specific background concentrations (whichever is greater) / /Consequently, the concentrations of these inorganics are not/c^jms^epred to be elevated on-site.

The geometric mean concentrations of aluminxOTv ydalcium, chromium, cobalt, iron, lead, magnesium, mercury, thallium and zinc detected in on-site surface soil samples were all less than the geometric means of the site specific baqjcground samples. However, the maximum detected concentration^ ofthe^fe^-j^jorganics on-site were all above the maximum regional back^rpun^ concentrations and/or the maximum site specific \back^ound concentration (whichever is greater) . This would indicate \hat the concentration of these inorganics are elevated at certain\^ocations on-site, but the overall concentration on-site is not excessively above background levels.

Elevated concent, num (11,000 mg/kg to 16,900 mg/kg) were detected samples SS-001, SS-003, SS 008, SS-011, SS-012 and 4. These soil samples were all collected in the area of rmer southern barge slip in the central pori:ion of the site. All other detected concentrations of aluminum on-site were below the maximum regional background concentrati^ (1^>€K)0 mg/kg).

~~Elevat f calcium (> 10,000 mg/kg) were detected at sampling pislnt o)/ghout the site. The highest concentrations~~

~~4-65 were detected in samples SS-007 (254,000 mg/kg) and SS-005 mg/kg) collected near the former southern barge slip. The regional background concentration of calcium was 2,800 mg/lc(~~

Elevated levels of chromium (22.6 mg/kg to 43 mg/kg) were detected in samples SS-001, SS-003, SS-008, SS-011, SS-012 and SS 014 which were collected near the former southern/barge slip. These concentrations are significantly above the/maximua^egional background concentration (2 mg/kg) but not sWieSjimxamum site specific background (36 mg/kg). ^ v x.

Elevated levels of cobalt (12.7 mg/kg. to 18.9 mg/kg) were detected in samples SS-002, SS-003, SS-008, SS-011, SS-012 and SS 014. Again, these elevated concentra;feions were located near the former southern barge slip. All othe/detected..^concentrations were below the maximum regional backgrouna\co^^l)tra^ti^ (10 mg/kg).

Elevated concentrations of iron wareV^detected in samples collected throughout the site. The highesv concentrations were detected near the former southern barge slip (35,600 mg/kg) and near the former fuel oil steraae tanks (31,900 mg/kg). The maximum regional background conc^nj^i^tiion of iron was 3,000 mg/kg.

The three highes' entrations of lead were found in locations spaced acr entire Pine Street Canal site in samples SS-005 (173 mg/kg)^ 18 (873 mg/kg) and SS-022 (172 mg/kg). Concentrations of lea ranging from 40 to 60 mg/kg were also noted across the site, The regional maximum background concentrati 0 mg/kg for lead. The maximum site specific backgroun ion was 159 mg/kg.

~~The entrations of magnesium were detected in samples SS-00 mg/kg) and SS-008 (10,900 mg/kg) which were~~

~~4-66 collected near the former southern barge slip. The maximum regional background concentration of magnesium was 10,000^o/k^v ^v~~

One elevated concentration of mercury (9.4 mg/kg) was detected ^ ^ in sample SS-032 collected near the former coal gasification plant. All other detected concentrations of mercury/vere less than 1 mg/kg. The maximum regional background concepxi^tion was 5.1 mg/kg for mercury.

~~One elevated concentration of thallium CTSJ lug/kg) was detected also in sample SS-032. All other detected cohqenj^rations were less than 0.5 mg/kg; the maximum site specific background concentration.~~

The highest concentrations of ^ing wer tected in samples SS-018 (614 mg/kg) and SS-020 (722 iple SS-018 was collected in the north portion of the s^ r the former fuel oil tanks; sample SS-020 was collected in th lUthern portion of the site near the St. Johnsbury Trucking Co. T maximum site specific background concentration of zinc was 138 mg/kg.

Antimony was not d site specific background samples, but was detected on-s t concentration was detected in sample SS-005 (38. cted near the former southern barge slip. All other de concentrations were below 15 mg/kg. The maximum regional d/concentration was 18 mg/kg.

Silver and cyanide were detected in on-site samples, but not in site sp^cificNbackground samples and were not reported in regional bacjCgrobiiid data. The highest concentration of silver (342 mg/kg) vtas o^ectedNinj sample SS-032 collected near the former coal gasification pl^t/ ySilver was detected in only one other sample at a concent^ation/of 1.1 mg/kg. The highest concentration of

~~4-67 cyanide (2.9 mg/kg) was detected in sample SS-029 collected sou of the Burlington Electric Department. The other detejffted concentrations of cyanide were all below 1 mg/kg.~~

Elevated concentrations of several inorganics were noted in the surface soil near the former southern barge slip. Other elevated concentrations were noted near the/ former coal gasification plant and the former fuel oil stos4ig6 ti£hics. The majority of inorganics appeared at or near backgrouo

~~4.5.4 Subsurface Soil~~

Subsurface soil samples were collected from soil borings and borings drilled for monitoring well installation. Sample depths ranged from one to 147 feet below t^e strriAce. One hundred and thirteen samples were collected and

~~4.5.4.1 Volatile Organic Analyses~~

Nineteen volatile organics were detected in subsurface soils. The most frequently detected volatiles (30-40% of samples) were benzene, toluene, ethylbenzene/v xylene and acetone. The remaining fourteen volatiles wer/s deteq:te3^^15% of the time or less. Four volatiles were detect^

l,l,2,2-tetrachloroetfi^K5e v)as detected in a sample from MW-10 (10-12 feet) at the north enff of the site at 3 ug/kg. 1,2 dichloroethene was detected in boring MW-02 at 5-7 feet (6 ug/kg) and at 12-ia--feet (34 ug/kg) , and in boring MW-01 at 5-7 feet (1,700 ug/kg|-r--^<5^ borings are on or near GE property. Chlorobenzei;{e was aetacted in BO-23, in the center of the site, at 25-27 feet. (5N^/kgi .1 Boring BO-23 also detected bromodichloro methane at 2SH27 r«4t/(l ug/kg) ; 1,1,1-trichloroethane at five feet

~~4-68 (5 ug/kg), 10-15 feet (5 ug/kg) and 25-27 feet (2 methylene chloride at 25-27 feet (93 ug/kg); and chlorofo feet (3 ug/kg), 10-15 feet (3 ug/kg) and 25-27 feet (7 ug/kg).~~

Besides Boring BO-23, bromodichloromethane was detected in boring MW-04, near the gas plant, at 145-147 feet (^/^212 ug/kg) and in boring MW-05, off site to the south, at 15 to 2 et^(4 ug/kg) and at 30-35 feet (1 ug/kg). Boring MW-05 alscj carbon tetrachloride at 15-20 feet (2 ug/kg); 1,1,1-tri ane at 15 20 feet (2 ug/kg) and at 30-35 feet (7 ug/kg); carH ^Ifide at 15-20 feet (210 ug/kg) ; methylene chloride at 10- t (6.2 ug/kg); and chloroform at 15-20 feet (13 ug/kg) and at 30-35 feet (10 ug/kg). Besides borings BO-23 and MW-05, 1,1,1-trichloroethane was detected in MW-04 at 145-147 feet/-ti7 ug/kg) .

Trans-1,3-dichloropropene was de n boring BO-05, in the southern barge slip, at 4-5 fee ug/kg) and at 18-20 feet (18 ug/kg). 2-butanone was detect BO-03, east of the turning basin, at 2-3 feet (14 ug/kg), 5-7 et (93 ug/kg) and at 24-25 feet (6 ug/kg). BO-03 also detected methylene chloride at 5-7 feet (98 ug/kg) and a .4 feet (220 ug/kg). 2-butanone was also detected in BO-13, .ington Electric Department, at 2-4 feet (820 ug/kg). jected carbon disulfide at 2 4 feet (210 ug/kg) arf jne at 14-16 feet (27 ug/kg). In BO-04, in Maltex Pon Itanone was detected at 20-25 feet (1,200 ug/kg). BO-01, in 5rthern former fuel storage area, it was detected at 10-15 feet (62 ug/kg) while methylene chloride at 5-10 feiet (62 ug/kg) and styrene at 10-15 feet (4 ug/kg) were also found./^2-bilt#inone was again detected in boring MW-02 (GE property)/at' 13^H^ ^eet (56 ug/kg). MW-02 also had: carbon disulfid^ atsl2-13 iJeejb (4 ug/kg) ; trichloroethene at 5-7 feet (15 ug/kg) andN^t 1^1^ f^et (23 ug/kg).

4-69 Besides borings BO-13, MW-02, and MW-05, carbon disulf detected in: BO-02, east of the turning basin, at 9-16 ug/kg); BO-19, west of the gas plant, at 19-20 feet (26 ug/kg); and in MW-04, in the gas plant area, at 4-6 feet (69,000 ug/kg). The concentration of carbon disulfide at MW-04 was orders of magnitude greater than any other carbon disulfide concentrat

Bromomethane was detected in BO-05, in th^ ge slip, at 4-5 feet (170 ug/kg). Besides borings nd MW-02, trichloroethene was detected in MW-01, east of (J 5-7 feet (1,600 ug/kg) and in MW-04 at 145-147 feet (2 ug/kg) 01 also had methylene chloride at 38-48 feet (36 ug/kg) Methylene chloride was also detected in: MW-11, by middle of canal, at 130 132 feet (40 ug/kg); BO-11, west /o€:>..,.^the Burlington Electric Department, at 5-7 feet (11 ug/kg) and ^it,lp^^t8-<^et (5 ug/kg) ; BO 14, by St. Johnsbury Trucking, at 8-\o Se^ f'S^JJ^/kg) ; BO-17, in middle of canal, at 19-21 feet (20 ug/lwO ; ajW in BO-21 at 30 feet (4 ug/kg). \ \

Styrene was detected in: MW-04, by the gas plant, at 4-6 feet (1,200,000 ug/kg), and feet (4,000 ug/kg); BO-16, in the canal, at 17-19 feet ( ); BO-17, in the canal at 11-13 feet (450,000 ug/kg (590,000 ug/kg), 15-17 feet (780,000 ug/kg), 17- 0 ug/kg) and 19-21 feet (110 ug/kg); BO-22, in the we£ at 19-20 feet (100 ug/kg); and BO 09, in the gas plant area, a -20 feet (13,000 ug/kg) and 25-30 feet (11,000 ug/kg).

Besides ;asly mentioned borings, chloroform was detected in: MW-sywt OX the site at 30-32 feet (3 ug/kg); MW-04, gas plant a 7 (11 ug/kg) ; MW-07, in the middle of the site, at 1 ug/kg) and at 20-22 feet (2 ug/kg); MW-11,

~~4-70 by the canal, at 10-12 feet (5 ug/kg); and in BO-22, i wetlands, at 19-20 feet (48 ug/kg).~~

There is very little pattern in either the vertical or horizontal distribution of the non BTEX volatiles. 1/2 dichloroethene was detected only around tha^ GE plant. Trichloroethane was only detected around the GE prmer gas plant area. Bromodichloromethane and 1,1,1-tr kne were only detected in the same three borings (BO , MW-05). The largest concentrations of styrene were all ii^ anal/gas plant area.

~~BTEXs~~

In contrast to the above, the and distribution of BTEXs exhibit a definite pattern, tration of BTEX compounds increases with depth, from sur bil and sediment down through the fill layer and into the peat Below the peat in the lower silt and clay, the concentration ecrease rapidly with depth. Table 4-19 is a summation table of total BTEX for each subsurface soil location^/''Tlrgure 4-15 is a concentration contour map of BTEX concentrataoifgNii\,_^e fill. The BTEX subsurface contamination plume iss em "I/' sj^p^^-jbhat includes the former gas plant, wetlands and troa^^sottthern nsriCf of the canal within a 1,000 ug/kg contour. A separate liK^g/kg contour encloses the former fuel storage area at the n^s:±^ end of the site. The maximum concentration of BTEX in the fill is at BO-17, in the canal, at 5,190,000 ug/kg. Figure 4-16 is a BTEX concentration contour map for BTEX coiricentrktlons in the peat. In the peat layer, the "L" shaped pliime/isstllrs, evident. The maximum BTEX concentration is again in

~~4-71 TABLE 4-19~~

~~TOTAL BTEX CONCENTRATIONS FOR SUBSURFACE SOIL SAMPLES~~

~~SUM OF LOCATION CODE MEASUREMENTS^ug/kg)~~

BO-01 •10-15 100. BO-01 •3-5 BO-01 •5-10 3 BO-02 •16-18 3 BO-02 •4-5 1 BO-02 •9-16 180 BO-03 •12-14 0 .0000 BO-03 2-3 25 .0000 BO-03 •5-7 928 .0000 BO-04 •1-5 0 .0000 BO-04 20-25 0 .0000 BO-04 •5-10 0 .0000 BO-05 16-18 000 BO-05- 18-20 00 BO-05 4-5 000 BO-06 10-1 ;oo .0000 BO-06- 10-15 '00 .0000 BO-06- 15-20 3la30&00 .0000 BO-06- 15-20 294J0OOO .0000 BO-06- 25-30 70000 .0000 BO-07- 10-12 111140 .0000 BO-07- 25-27 5 .0000 BO-08- 10-11 0 .0000 BO-08- 12-13 0 .0000 BO-08- 8-10 0 .0000 BO-09- 15-20 888000 .0000 BO-09- 15-20 908000 .0000 BO-09- 15-20 877000 .0000 BO-09- 15-20 321000 .0000 BO-09- 15-20D 334000 .0000 BO-09- 15-20D 359000 .0000 BO-09-25-30 287000 .0000 BO-10- 22:?: 58000 .0000 BO-10 41200 .0000 BO-10 14140 .0000 BO-1 1023000 .0000 BO- 23 .0000 BO-li 8 .0000 BO-11- 17 .0000 B0-12A 1700 .0000 B0-12A 0 .0000 B0-12B 5070 .0000 B0-12B 3460000 .0000

~~4-72 TABLE 4-19 (Continued)~~

~~TOTAL BTEX CONCENTRATIONS FOR SUBSURFACE SOIL SAMPLES~~

~~SUM OF LOCATION CODE MEASUREMENTS^ug/kg)~~

BO-13-14-16 BO-13-2-4 BO-13-20-22 BO-14-25 BO-14-4 BO-14-8-10 0 BO-15-0-5 0 .0000 BO-15-17-19 0 .0000 BO-15-23-25 0 .0000 BO-16-13-15 4120000 .0000 BO-16-13-15D 2390000 .0000 BO-16-17-19 JOOOOO .0000 BO-16-27-29 0000 BO-17-0-5 .ci;Doo BO-17-11-13 000 BO-17-13-15 )00 .0000 BO-17-15-17 >490000 .0000 BO-17-17-19 |86X)00 .0000 BO-17-19-21 ^782 .0000 BO-19-07 0 .0000 BO-19-12 140000 .0000 BO-19-15-16 1234000 .0000 BO-19-19-20 608 .0000 BO-20-16-18 0 .0000 BO-20-27-30 0 .0000 BO-20-7-8 0 .0000 BO-20D-27-30 0 .0000 BO-21-14-18 0 .0000 BO-21-14-18 0 .0000 BO-21-30 0 .0000 BO-21-7-8 0 .0000 B0-22-fl3-16 1530000 .0000 BO-22-19 3390 .0000 BO-23-( 0 .0000 B0-237^-i 0 .0000 BO-23^: 15 .0000 B0-: 0 .0000 B0-: 0 .0000 BO-2 3' 0 .0000 BO-23-25-^ 0 .0000

~~4-73 TABLE 4-19 (Continued)~~

~~TOTAL BTEX CONCENTRATIONS FOR SUBSURFACE SOIL SAMPLES~~

~~SUM OF LOCATION CODE MEASUREMENTS^(ug/kg)~~

MW-01-38-40 MW-01-5-7 MW-02-12-13 MW-02-13-14 MW-02-27-29 O.OOOT MW-02-5-7 1.0000 MW-03-0-2 0.0000 MW-03B-10-12 384600.0000 MW-03B-15-17 0.0000 MW-03B-64-66 0.0000 MW-04-145-147 574.0000 MW-04-145-147 0000 MW-04-145-147 3 63."^00 MW-04-28-30 158'3T3VOOOO MW-04-4-6 982/ZK>00.0000 MW-04-4-6 \93aoooo.oooo MW-05-10-15 0.0000 MW-05-110.15D 0.0000 MW-05-15-20 0.0000 MW-05-15-20 0.0000 MW-05-15-20D 15.0000 MW-05-15-20D 0.0000 MW-05-15-20D 18.0000 MW-05-30-35 0.0000 MW-05-30-35D 0.0000 MW-07-0-2 0.0000 MW-07-10-17 0.0000 MW-07-20-22 0.0000 MW-07-70-90 0.0000 MW-08-10-12 0.0000 MW-08-15-17 0.0000 MW-08-3( 0.0000 MW-08 0.0000 MW-09/ 0.0000 MW-( 0.0000 MW 0.0000 MW 0.0000 MW-10 5.0000 MW-10-10-^ 2.0000 MW-11-10-12" 3508.0000 MW-11-130-132 0.0000 MW-11-19-21 1931000.0000 MW-llB-25-27 270.0000

~~4-74 N 0 §ilii!l88l8S88888~~

~~SCALE (FEET)~~

~~100 200 300 400~~

~~• PEER WELLS~~

~~• PEER BORINGS~~

~~• PREVIOUS INVESTIGATIONS~~

~~(CONCENTRATIONS IN PPB)~~

~~IN RLL (SOIL SAMPLES) FIG. 4-15 PINE STREET CANAL SITE J~~

~~4-75 N I I i I I I I 8 8 § 8 § I 8 8 § 8 (D §§§S§§§§§§§§§§§§§ lOLBUim STNCET~~

~~SCALE (FEET) 100 200 300 400~~

~~• PEER WELLS~~

~~• PEER BORINGS~~

~~L^KE CHAMPLWN~~

~~IN PEAT (SOIL SAMPLES) FIG. 4-16 PINE STREET CANAL SITE~~

4-76 northern barge slip, suggesting a possible secondary contam^a source. For the silt/clay soils below the peat layer, to of 30 feet below ground surface, the concentration contour is similar to that for the peat layer, but the total concentrations are significantly less (Figure 4-17). The maximum concentration of BTEX in the lower silt and clay is 3,000,000 ug/]j;g in a sample from BO-17 taken just below the peat layer. Th as the only sample above 1,000,000 ug/kg in the lower silt/ nly two other samples (BO-16, BO-09) were above 10 ^kg. No concentrations of BTEX were found in soil sampl^ 30 feet from the ground surface (Figure 4-18).

~~4.5.4.2 Semivolatile Organic Analyses~~

~~Twenty-seven semivolatiles were in subsurface soils. Seventeen PAH's had the greatest s and highest frequency of detection. Five non-PAH aem es were detected only once.~~

3,3'-dichlorobenzidine was detected once in boring MW-08, in the west area of site, at ::02 feet (870 ug/kg) . 2-methylphenol was detected once at BO- he E-W drainage ditch north of the gas plant, at 25-30 fe 4-nitrophenol was detected once at BO-19, west o 19-20 feet (800 ug/kg). Di n-octyl-phthalate was de once at BO-21, in the middle of the site, at 7-8 feet (150 ug/j^ 2,4-dimethyl phenol was detected once at MW-11, near the southei barge slip, at 10-12 feet (1,700 ug/kg). Benzoic,-«c±d-^as detected twice above background level of 340 ug/kg: B0/02^'~east >3f the turning basin at 9-16 feet (900 ug/kg) and B0-2y; ^n thert^ddleo f the site, at 14-18 feet (630 ug/kg).

~~4-77 N 8 8 I 8 8 iisSI8S§8888 VT\ i s 8 i i §§§§§§§§§§§§ ajum tTncCT I I I I I I I I I I I I~~

~~BTEX TO ADEPTH OF 30 FEET IN LOWER SILT/CLAY FIG. 4-17 PINE STREET CANAL SITE~~

~~4-78 iilli!i88§8888888 I I I I I I I I I I I I I I I I I~~

~~SCALE (FEET) 100 200 300 400~~

~~• PEER WELLS~~

~~• PEER BORINGS~~

~~LAKE CHAMPLAIN~~

~~BTEX BELOW ZO^E T IN LOWER SILT/CLAY (SOIL SAMPLES) FIG. 4-18 PINE STREET CANAL SITE~~

4-79 . Butylbenzylphthalate was detected three times ab background level of 130 ug/kg: BO-14, at the south end of site, at 8-10 feet (1,800 ug/kg); BO-15, in the turning basin, at 17-19 feet (170 ug/kg; and BO-23, north of the E-W drainage ditch by the gas plant, at 3-5 feet (260 ug/kg).

~~Di-n-butylphthalate was detected once abo ckground level of 500 ug/kg at boring MW-11, near the so krge slip. at 10-12 feet (1,200 ug/kg).~~

Bis(2-ethylhexyl)phthalate was detected nine times above the background concentration of 1,600 ug/kg. Of these, five were at concentrations more than ten times the/-biank levels for this common laboratory contaminant: BO-03, at the n9rtlielT4-.^f the site, at 2 3 feet (24,000 ug/kg) and 5-7 feet (4a,OOo7bg/kg/; BO-05, in the southern barge slip, at 18-20 feet (llOVOOO i:^/kg) ; MW-02, on the GE property, at 13-14 feet (27,000 ug/kg)\ahd MW-10, at the north end of the site, at 10-12 feet (24,000 ug/Kg).

PAH's make up t st extensive concentrations of semivolatiles in subs Is. As with the BTEX's, the concentration of tota es with depth, from surface soil and sediment dow ill layer and into the peat layer. Below the peat, i pwer silt/clay, the concentrations decrease rapidly with depth. ure 4-19 is a cross section with concentration plots from several borings superimposed. This figure graphically illustrates how the peat is the strata containing the highest PAH/concei?trations.

~~Ta ummation table of total PAH values for all subsurface re 4-20 is a concentration contour map of total PAH Ions in the fill. Total PAH concentrations of~~

~~4-80~~

~~TABLE 4-20 SUMMATION CHART FOR TOTAL PAH CONCENTRATIONS FOR SUBSURFACE SOILS~~

~~SUM OF LOCATION CODE MEASUREME g/kg)~~

BO-01-10-15 BO-01-3-5 13641 BO-01-5-10 BO-02-16-18 BO-02-4-5 BO-02-9-16 000 BO-03-12-14 0000 BO-03-2-3 0000 BO-03-24-25 0000 BO-03-5-7 0000 BO-04-1-5 0000 BO-04-20-25 0000 BO-04-5-10 0000 BO-05-16-18 0000 BO-05-18-20 ^2600 000 0 BO-05-4-5 '5000 000 0 i BO-06-10-15 12830 000 0 BO-06-15-20 13200 000 0 BO-06-15-20 ilOOO 0000 [ BO-06-25-30 264710 0000 BO-06-25-30 338200 0000 BO-07-10.12 1276000 0000 BO-07-25-27 75880 0000 c BO-08-10-11 0 0000 BO-08-12-13 0 0000 BO-08-8-10 0 0000 c BO-09-15-20 18725000 0000 BO-09-15-20D 13967000 0000 BO-09-15-20D 20318000 0000 E BO-09-25-30 390400 0000 BO-09-25-30 1022400 0000 BO-10-22-24 105720 0000 BO-lO-ri 13938 0000 L BO-K 54300 0000 B0-: 88110001 000 0 BO^ 24390 0000 BO-i< 1960 0000 B0-: 5980|. 000 0 B0-12A-^ 11030 0000 BO-12A-6 0 0000 BO-12B-17-l§' 196500

~~4-82 TABLE 4-20 (Continued) SUMMATION CHART FOR TOTAL PAH CONCENTRATIONS FOR SUBSURFACE SOILS~~

~~SUM OF LOCATION CODE MEASUREMENTS (ug/kg)~~

BO-12B-7-8 BO-13-14-16 BO-13-2-4 BO-13-20-22 BO-14-25 [ BO-14-4 BO-14-8-10 BO-15-0-5 BO-15-17-19 E BO-15-23-25 BO-16-13-15 BO-16-13-15D BO-16-17-19 BO-16-27-29 BO-17-0-5 i BO-17-11-13 BO-17-13-15 BO-17-15-17 BO-17-17-19 [ BO-17-19-21 BO-19-07 BO-19-12 I! BO-19-15-16 BO-19-19-20 BO-20-16-18 BO-20-27-30 BO-20-7-8 BO-20D-27-30 BO-21-14-18 BO-21-30 BO-21-7-8 BO-22-13-16 [ BO-22-ia=Z0 BO-2: B0-: BO BC BO BO-2:

~~4-83 TABLE 4-20 (Continued)~~

~~SUMMATION CHART FOR TOTAL PAH CONCENTRATIONS FOR SUBSURFACE SOILS~~

~~SUM OF LOCATION CODE MEASUREMENTS (ug/kg)~~

MW-01-38-40 12616/rooD o MW-01-5-7 55100 .0000 MW-02-12-13 /o ,>ioo6 MW-02-13-14 .obta MW-02-27-29 2400 >a()oo MW-02-5-7 0 .ootx^ MW-03-0-2 8928 .0000 ) MW-03B-10-12 3372000 .0000 .1 MW-03B-15-17 71 .0000 MW-03B-64-66 0 .0000 MW-04-145-147 71 .0000 MW-04-28-30 ----5^900 .0000 MW-04-28-30 158^5^0.,000 0 MW-04-4-6 52>00000><^000 0 MW-05-10-15 \//^' 0000 i MW-05-10-15D 0000 MW-05-15-20 V /\ °"°'000 0 MW-05-15-20D \ / ^2°000" 0 MW-05-30-35 V 0. 0000 MW-05-30-35D 0, 0000 MW-07-0-2 0. 0000 MW-07-10-17 0. 0000 MW-07-20-22 0. 0000 MW-07-70-90 0. 0000 MW-08-10-12 0. 0000 MW-08-30-32 0. 0000 MW-08-5-7 0. 0000 MW-09-14-16 0. 0000 MW-09-3.5-5 0. 0000 MW-09-40-42 0. 0000 MW-10-0-2 15510. 0000 MW-10-10-12 12300. 0000 MW-11-; 1286800. 0000 MW-1] 0. 0000 MW 22620000. 0000 MW 37720. 0000

~~4-84 N SSfiiil 8 8 8 8 8 8 8 8 8 8 i § § i § § i §§§§§§§§§§ I I I I I I I I I I I I I I I I I SCALE (FgT) 100 200 300 400~~

~~• PEER WELLS~~

~~• PEER BORINGS A PREVIOUS r INVESTIGATIONS~~

~~LAKE CHAMPLAIN~~

~~[ [ r L~~

[

~~y^A L PAH'S IN FILL (SOIL SAMPLES) FIG. 4-20 PINE STREET CANAL SITE~~

4-85 1,000 ug/kg or more are present in the southern end of th^ the former gas plant area, the wetlands, the northern poj GE property, the canal and southern barge slip, the turnii and former fuel storage area at the north end of the site. The area of greatest concentration of total PAH in the fill (> 1,000,000 ug/kg) is centered on the former ga plant area, wetlands, south end of the canal and the southern e slip. This contour map shows that total PAH concentratioi fill are widespread but still center on the gas plant. and canal. The concentration contour map for carcinogenic j.n the fill (Figure 4-21) is similar to that for total PAH's e total concentration values are lower.

Figure 4-22 is the concentration contour map for total PAH's 1 in the peat. The "L" shaped soil coirtamin?mt...^ume similar to that for BTEX is evident. The largest totair~l^ concentration in the peat is 162,000,000 ug/kg at boring V? /in the canal. PAH I concentrations in the peat above l,000,\oo\ug/kg are found in the gas plant area (MW-3, B0-12B, BO-IO, BO-0€j/BO-22) and canal (BO [ 16, BO-17, MW-11). There is only a small concentration contour at the north end of the sit. The PAH contamination at this end of c the site is more exten the fill than in the lower strata. The concentration c carcinogenic PAH's is again [ similar to that s only at lower overall concentrations (Figure Carcinogenic PAH concentrations greater than 1,000,000 ug, :e centered in the gas plant area I (BO-09), wetlands (BO-22) and southern end of canal (BO-16, BO-17, [ MW-11). ay soils below the peat layer, to a depth of nd\ surface, the concentration contour outlines similar to the peat layer, but the total ignificantly less (Figure 4-24). The maximum

~~4-86 /2 N iil§§!i88l8S8888S §§§§§§§§§§§§§§§§§ lOLmjwN mcET 0 I I I I I I I I I I I I I I I I I SCALE (FgT)~~

~~100 200 300 400~~

~~• PEER WELLS~~

~~• PEER BORINGS A PREVIOUS INVESTIGATIONS~~

~~1 LAKE CHAMPLAiN 1~~

~~cSqNOGENIC PAH'S IN RLL (SOIL SAMPLES) FIG. 4-21 PINE STREET CANAL SITE~~

~~4-87 4-88 N 11111118818888818 • 0 KILaURN STnEET~~

~~SCALE (FEET) 100 200 300 400~~

~~• PEER WELLS~~

~~• PEER BORINGS~~

~~LAKE CHAMPLAJN~~

~~CARCr •NIC PAH'S IN PEAT (SOIL SAMPLES) FIG. 4-23 PINE STREET CANAL SITE~~

~~4-89 N 8 8 8 8 I § 18 8 18 8 8 8 8 18 § § § § i §§§§§§§§§§§ IQLBum STREET 0 Illl lilli~~

~~SCALE (FEET) 100 200 300 400~~

~~• PEER WELLS~~

~~• PEER BORINGS~~

~~LAKE CHAMPLAJN~~

~~(CONCENTRATIONS IN PPB)~~

~~TOTAL P A DEPTH OF 30 FEET IN LOWER SILT/CLAY FIG. 4-24 PINE STREET CANAL SITE~~

4-90 concentration of total PAHs in the lower silt/clay is 27,^0,^00 ug/kg in BO-17. Only one other sample had a tojl concentration greater than 1,000,000 ug/kg (B0-16)> carcinogenic concentration contour map (Figure 4-25) is similar but with a maximum concentration of 4,300,000 ug/kg at BO-16.

There are two areas where total PAH concentr ns (Figure 4 26) and carcinogenic PAH concentrations (Figu are found below 30 feet from ground surface: MW-01 just property to the east had a total PAH concentration of 1 ug/kg and a carcinogenic PAH concentration of 833 ug/kg in >K solkl sample collected at 38-4 0 feet below ground surface. While noxorings on i: GE property go deeper than 30 feet, a soil sample collected at 27 29 feet showed a total PAH concentration of 2,400 ug/kg. This suggests the possibility that PAH cc i^on may exist below 30 feet on parts of the GE property;\th^ cation in which i contamination was found below 30 feet' -^4 (near the former coal gasification plant), in a sample from 145 to 147 feet (BTEX, 360 ug/kg; Total PAH, 71 ug/kg) s sample was taken in [ the till layer, just above bedrock. Given 'the great depth of clay above and the lack of contajnination in groundwater screened over [ the same interval, the/coptamdnation in this sample is suspected of being an outlier. [ 4.5.4.3 Pesticides/P' [ Fourteen pesticides were aetected in subsurface soils. Gamma- r chlordane. was the most frequently detected pesticide (8 out of I 113): Gamm dane was detected at: BO-06, E-W drainage ditch, at 10-15 fe 0 >4g/kg) and 25-3 0 feet (15 ug/kg) ; BO-O, west of the gas/D] -20 feet (540 ug/kg) and at 25-30 feet (16 ug/kg); south end of site, at 4 feet (28 ug/kg) and at 8-10 fee kg); BO-15, in the turning basin, at 1-5 feet

~~4-91 N I I I i i § I 8 8 I 8 8 8 8 8 § 8 /T\ sssssssssssssssss ttxaufHaTPest I I I I I I I I I I I I I~~

~~SCALE (FEET)~~

~~100 200 300 400~~

~~• PEER WELLS~~

~~• PEER BORINGS [ I I LAKE CHAMPLAIN i [~~

~~[• li [~~

~~JAROINOGENIC PAH'S TO A DEPTH 30 FEET IN LOWER SILT/CLAY FIG. 4-25 PINE STREET CANAL SITE~~

~~4-92 N I I 8 8 8 § 18888888888 i i i i § §S§§§§§§§§§ § miauMNvraEEr 0 I I I I M I I I 1 1 i t I I I I SCALE (FEET) 100 200 300 400~~

~~• PEER WELLS I • PEER BORINGS~~

~~LAKE CHAMPLAIN c E [ I I~~

~~TOTAL PAH'S BELOW 30 FEET IN SILT/CLAY (SOIL SAMPLES) FIG. 4-26 PINE STREET CANAL SITE~~

~~4-93 N I I I B I ! I 8 8 I 8 8 8 8 81 8 /T\ sssssssssss§sss§s MLCUnNSnCE T~~

~~^^ I I I I I I I I I I I I I I I I I -31-00~~

~~•S-KOO SCALE (FEET) •1-fOO 100 200 300 400 O'fOO~~

~~14-00~~

~~• PEER WELLS 2-fOO~~

~~a-MM • PEER BORINGS 4-I-00~~

~~9+00~~

~~•4-00~~

~~74-00~~

~~•4.00~~

~~•4-00 LAKE CHAMPLAIN 104-00 114-00~~

~~12-t-OO~~

~~134-00~~

~~14400~~

~~154-00~~

~~1«400~~

~~17400~~

~~1S4-00~~

~~1>4-00~~

~~204-00~~

~~214-00~~

~~224-00~~

~~23400~~

~~244-00~~

~~254-00~~

~~26400~~

~~— 27+00 — 28+00~~

~~— 29400~~

~~— 30+00 (CONCENTRATIONS IN PPB) lAKESIOeAVE Mk /^ • ^.RbfNOfeiENIC PAH'S BELOW 30 FEET \py/ER SILT/CLAY (SOIL SAMPLES) FIG. 4-27 PINE STREET CANAL SITE~~

~~4-94 (4.8 ug/kg); and MW-4, in the gas plant area, at 4-6 fee ug/kg).~~

Endosulfan I was detected at: BO-05, in the southern barge canal, at 4-5 feet (490 ug/kg); BO-09, in the gas plant area, at 15-20 feet (750 ug/kg) ; and at MW-04, in the gas p^i^ area, at 28 30 feet (76 ug/kg).

Endosulfan II was detected with EndosulfanSI at^W-04, 28-30 r feet (120 ug/kg). Methoxychlor was detected at: BO^l, a^hind the BED, at 5-7 feet (2,000 ug/kg); and MW-04, in the gas^^Tant area, at 4-6 feet (57,000 ug/kg). Dieldrin was detected at: BO-05, in the southern barge slip, at 16-18 feet (980 ug/kg); BO-11, behind the BED, at 5-7 feet (310 ug/kg); ^[n^->rfe-JlW-04, in the gas plant area, at 4-6 feet (8,600 ug/kg). i Endrin was detected at BO-05, ^ 4^5 feet (360 ug/kg); Aldrin was detected at MW-04, at 28-30 feet\(9.2 ug/kg); 4,4'-DDT c was detected at BO-14, at 8-10 feet (65 ug/kg); 4,4'-DDD was detected at: BO-05, at 16-18 feet (720 ug/kg) and BO-14, at 8-10 [ feet (8.4 ug/kg); Alp detected at MW-04, at 4-6 feet (2,600 ug/kg); Delta pted at: BO-05, at 4-5 feet (570 [ ug/kg), MW-01, east<^ feet (280 ug/kg); and at MW 04, at 28-30 feet (9. Gamma-BHC was detected at BO-09, gas plant area, at 15 t (39 ug/kg); Archlor-1254 was I detected at BO-11, behind ED, at 19-21 feet (830 ug/kg) ; L Heptachlor epoxide was detected at BO-05, at 4-5 feet (150 ug/kg). ticides were detected in the gas plant area and n\barge slip. The area behind the Burlington nd north of St. Johnsbury Trucking was where feticides were detected, except for the gamma

~~4-95 chlordane, found in the turning basin. Most of the pestici^fes^we found from one to 30 feet below the surface.~~

~~No PCB's were detected in any soil samples.~~

~~4.5.4.4 Conclusions~~

~~There is extensive organic contamination/at~~

[ 4.5.4.5 Inorganic An^ys r An extensive number dS/ inorganics were detected in the subsurface soil, as would be expected in any soil samples. Table inorganics detected in the subsurface soil, the I ted concentrations and the geometric mean of pn$. The concentrations of inorganics in the compared to site specific background surface 4-17) and regional background soil' samples

~~4-96 TABLE 4-21~~

~~INORGANIC CHEMICALS DETECTED IN SUBSURFACE SOILS PINE STREET CANAL SITE. BURLINGTON, VERMONT~~

GEOMETRIC CONTRACT RANGE OF MEAN OF LOCATION NUMBER REQUIRED DETECTED DETECTED OF CHEMICAL OF DETECTIONS/ OUANTITATION CONCEN. CONCEN. MAXIMUM CLASS NO. OF SAHPLES LIMIT (ug/ko) (ug/kg) (ug/kg) CONCEN.

~~Inorganics~~

Aluminum 40 463-32,200 8.706 BO-Ol-S-10 Antimony 12 2.9-27.3 6.5 BO-16-13-15 Arsenic 2 0.42-64.0 6.4 BO-13-14-16 Bariun 40 4.9-216 47.0 MW-02-12-13 Beryltium 1 0.3-13.0 0.93 BO-22-19-20 Cadnium 1 1.0-15.7 1.62 MU-02-12-13 Calcium 1000 15-49.700 6.198 MU-04-145-147 I Chromium 107/113. 2 1.1-1.850 22.5 MU-02-12-13 VO Cobalt 98/11 10 3.0-25.0 10.8 BO-OS-18-20 -J Copper 103/113 5 2y»»210 27.8 MU-02-5-7 Iron 113/113 20 25A'-^r 14.1 BO-17-0-5 Magnesiui 113/113 1000^ U

~~• protMbte or possible hunan carcinogen PAH. (Table 6-1-1) to determine if contaminant concentration^ w: elevated on-site.~~

The geometric. mean concentrations of Barium, Beryllium, Arsenic, Magnesium, Manganese, Nickel, Potassium and Sodium wereall found to be below approximately 2 times the geometric mean of the site specific background samples. The maxim oncentrations I detected of these inorganics were also below t^ regional background values. Consequently the cone of these I inorganics are not considered to be elevated on Calcium, iron, and zinc were detected at concentrations exceeding site specific and regional maximum background concentrations. The highest concentration of calcium (49,700 c mg/kg) and iron (171,000 mg/kg) we in soil samples from monitoring well MW-04, located di of the old coal II gasification plant. The high concentr calcium was detected at a depth of 145 feet; the high concent' .on of iron was detected at 4 feet. The highest concentration inc (3,410 mg/kg) was [ detected in boring B0-12B, located southwest of the coal gasification plant at epth of seven feet. In general, [ concentrations of cal n, and zinc are highest in the area adjacent to the old/Co on plant; however, there does c not appear to be any n; elevated concentrations were detected in samples from depths of 3 to 145 feet. The I maximum regional backgroui^ jncentrations of calcium, iron and zinc are 2,800 mg/kg, 3,000 mg/kg and 45 mg/kg respectively. The maximum 6ite specific background concentrations of calcium, iron I and zinc v^'reTToiO mg/kg, 17,000 mg/kg and 100 mg/kg respectively.

~~mean concentrations of aluminum, chromium, cobalt, c<^pe" a^, and vanadium were all less than .2 times the geometric mfei of/the site specific background concentrations.~~

4-98 However, the maximum detected values for these inorganics we^ above the maximum regional background concentrations, inc thai: specific areas may have elevated concentrations inorganics, but the overall site concentrations are not excessively above the site specific background.

Elevated concentrations of chromium wer detected in subsurface samples from MW-02 (862 mg/kg at a d feet and 1850 mg/kg at 12 feet) and MW-04 (190 mg/k .). The concentrations detected at these two sampling pd generally r an order of magnitude greater than the remaiqin^ detected concentrations on-site. The maximum regional X^ckground I concentration of chromium was 2 mg/kg; the maximum site specific F background concentration was 15.9 mg/kg. Elevated levels of aluminum ( and cobalt (>15 mg/kg) were noted in numerous subsur pies from borings and wells located throughout the site ths from 5 to 40 feet. The maximum regional background concen ions of aluminum and [ cobalt are 10,000 mg/kg and 10 mg/kg respectively, maximum site specific background concentrations are 9,790 mg/kg and 9.7 mg/kg [ respectively.

[ Two of the highc'st'i^etyctedsconjfcentrations of copper were also noted from MW-02. The\conc^trations detected at depths of 5 feet [ (4210 mg/kg) and 12 feetN(4 44sing/kg) were generally on order of magnitude higher than most >o£ the on-site concentrations. An elevated concentration of copper was also noted from MW-04 (678 r mg/kg) at a,-4ie^h of 4 feet. The maximum regional background 3per is 20 mg/kg.

~~detected concentrations of lead were from MW- depth of 12 feet) and BO-17 (764 mg/kg) at a~~

4-99 depth of 5 feet. BO-17 is located in the central portion^ canal near the former southern barge slip. Elevated levels (>i00 mg/kg) were noted in subsurface soil samples from^ borings and wells spaced throughout the site, but most frequently in the central portion of the site just east of the former southern barge slip from BO-20 (116 mg/kg at 7 ft.), BO-5 J195 mg/kg at 4 ft.), and BO-23 (195 mg/kg at 5 ft.). The >toa?cimum regional background concentration of lead was 20 mg/kg.

The highest detected concentration of vanadium ^^s from the subsurface soil samples at MW-11 (2530 mg/kg at a a^trtsof 10 ft and 576 mg/kg at 19 ft.). MW-11 is located directly aajacent to the former southern barge slip in the central portion of the site. Vanadium was detected in boring 12B at a concentration of 209 mg/kg; all other detected concentra^ions~~w«a::e less than 100 mg/kg. The maximum regional background conceh^^Ti^ion^f vanadium was 70 mg/kg. \ \/ ,

Antimony, cadmium, mercury, seleniVm/ silver, thallium and cyanide were detected 22 to 3 6 out of the 113 subsurface soil samples. These inorganipsêre either not detected in background samples or the maximupr bâpkgôund concentrations were below the maximum on-site conce

Elevated concen-^satidus of antimony were detected in sxibsurface soil samples fi^9m "&0-16 (27.3 mg/kg at a depth of 13 feet) and BO-05 (16 mg/kg at a depth of 18 feet), located near the former southern barge slip; and from MW-02 (14.8 mg/kg at 5 ft. and 29 mg/kg at-T2~tt..). All other detected concentrations of antimony were helow/^the maximum regional background concentration (10 mg/kg)^

4-100 The highest concentrations of cadmium were detected\in subsurface soil samples from MW-02 (15.7 mg/kg at 12 tt.) Ana.^^oxB> MW-04 (11 mg/kg at 4 ft.). All other detected concentrations cadmium were less than 5 mg/Kg. Cadmium was not detected in site specific background samples and not reported in regional background data.

An elevated level of mercury (18 mg/kg) ed in one subsurface soil sample from MW-01 at a depth<^f MW-01 is located at the far southern end of the canal. A" detected concentrations of mercury were below the max regional background concentration (5.1 mg/kg).

The highest concentrations o selenium were detected in subsurface soil samples from BO-16 at a depth of 13 ft. and 4 mg/kg at 17 ft.); BO-17 (6.7 t. and 3.9 mg/kg at 13 ft.); and MW-11 (7.1 mg/kg and 6.3 ug/kg at 19 ft.). These sample points are all locat ear the former southem barge slip. Other detected concentration f selenium ranged from 0.6 to 4.6 and were located throughout the site. The maximum regional background concentration of selenium was 0.5 mg/kg.

The highest c ^ of silver were detected in subsurface soil sam; 75.6 mg/kg at a depth of 5 ft.) and MW-02 (10 mg/kg at and 9.6 mg/kg at 12. ft.). All other detected concentrations of r were 2 mg/kg or less. Silver was not detected in site specific background samples and not reported in regional background data.

~~oncentrations of Thallium were detected in es from MW-04 (2 mg/kg at 145 ft.), MW-05 (2 30 ft.) and BO-23 (2 mg/kg at 5 ft., 10 ft., OA and BO-23 are located northwest and southwest~~

~~4-101 of the former coal gasification plant; MW-05 is located the Pine Street Site. Thallium was not detected in site background samples and was not reported in regional ba data.~~

Elevated levels of cyanide were detected in subsurface soil samples from MW-04 (666 mg/kg at a depth of 4 f/• ^» BO-09 (39.8 mg/kg at 15 ft.), BO-11 (162 mg/kg 15 5 ft.), mg/kg at 7 ft.), B0-12A (13 mg/kg at 11 ft.), and BO-10 at 9 ft.). These sampling points were all clustered west an west of the former coal gasification plant and near the Burl Electric Department. An elevated concentration of cyanide was so noted in BO-17 (30.1 mg/kg at 5 ft.) located near the former southern barge slip. Cyanide was not detected in site specific background samples and was not reported in regioi'iai,.,background data. All remaining on-site detections of cyaHid'^'-weare a^~~i?oncentrations of 3 mg/kg or less.

Elevated concentrations of inorgaiii.cs appear to have accumulated in the subsurface soil around the former southern barge slip and the former coal gasification plant. A number of elevated concentrations of inoroizmics vtere also found in the subsurface soil at MW-02 located sout^hwest of tHiSv^canal turning basin.

~~4.5.4.6 Volume Esti~~

Volume calculations werVperformed by dividing the relevant area into squares and calculating the square footage of the contaminated-~crrea. The areas enclosed by the 1,000 ug/kg, 10,000 ug/kg, anfcl yar7^ao,aQ0 ug/kg total PAH concentration contours were calculated^ Theh, ah average thickness was determined for each square aj:id^iie t)'iiakness of the square was multiplied by the respective surfctce/area to obtain a volume estimate.

4-102 The area enclosed by the 1,000 ug/kg PAH concentration in the fill is 193,300 square yards or approximately 39 ac areas enclosed by the 10,000 and 1,000,000 ug/kg PAH concen contour lines are 126,000 and 48,000 square yards respectively.

~~Thicknesses ranged from three feet at the o er edge to 25 feet at the coal gasificaton plant and 18 feet e canal. The resulting volumes are presented below:~~

~~Soil PAH Contaminant Contour fug/kg) > 1,000,000 192,000 > 10,000 633,000 > 1,000 966,500~~

~~4.6 Groundvater Investigation Resu~~

Groundwater samples were collectved ^from monitoring wells installed during the Remedial Investigation and from wells installed during previous studies that were reconditioned during the RI. Fifty-eight samples were collected from fifty- one wells. The 58 include four duplicates and repeat samples from three v nated wells (102B, 104A, 104B). Table 4-22 lists ounds detected, frequency of detection and other pe t data. Additionally, three wells on Blodgett property were n March 1990 for which there is no analytical data as of yet. of laboratory error, there are no semivolatile analysis results for seven wells at the north end of the sijbe—(MW-lOA, lOB and UM 1-5) . Semivolatile analyses gathered/fronrweirs UM 1-5 in 1986 were used for the north end of the site.< WellsXMWy-SA and MW-5B (off-site, south of site) were used to"^st^bJ.ishyb^kground water quality.

~~4-103 GROUNDWATER TABLE 4-22~~

~~ORGANIC CHEMICALS DETECTED IN GROUNOUATER PINE STREET CANAL SITE. BURLINGTON, VERMONT~~

GEOMETRIC GEOMETRIC FEDERAL VERHONT PRIMARY CONTRACT RANGE OF MEAN OF MEAN OF LOCATION DRINICING GROUNOUATER NUMBER OF REQUIRED DETECTED OFF-SITE DETECTED OF UATER QUALITT CHEMICAL DETECTIONS/ QUANTITATION CONCEN. UELL HU-05 CONCEN. MAXIMUM STANDARDS STANDARDS CLASS CHEN I « OF SAHPLES LIMIT (ug/L) (ug/L) (ug/L) CONCEN. (og/D* (ug/L)

Volatiles Toluene 21/58 2-2500 22 B-104A 2000 PMCL 2.420/1,210 Total Xyleri 18/58 1-1500 60 MU-llB 10.000 PMCL 400/200 Benzene 16/58 1-4000 73 HU-4A 5 MCL 5/0.5 Ethylbenzene 2-2000 68 B-104A 700 PMCL 680/340 Acetone 11-550 78 200 HU-4A Methylene Chloride 5-530 87 HU-4A 5/2.5 Carbon Disulfide 2-26 7 B102B Chloroform 1-7 3 7 HU-SB 100 NIPDUR 2-Hexanone 10-280 39 14 MU-11C Vinyl Chloride 43-1100 217 MU-2A 2 MCL 2.0/0.2 1,2-Dichloroethene (total) 9 HU-IA 70/35 2-Butanone 190 HU-IA Trichloroethene 1-25 B-102B 5 MCL 5/0, Styrene 40-440 MU-4A 5/100 PMCL 5/0.

Semi-Volatiles Naphthalene 16/58 10-1250 2000 LTHA 2-Hethylnaphthalene 12/58 10-1250 Acenaphthylene 11/58 10-1250 Acenaphthene 12/58 10-1250 Dibenzofuran 7/58 10-1250 l-» Fluorene 12/58 10-1250 7-15.000 O 4-Hethylphenol 3/58 10-1250 6-19 9 4^ Phenanthrene 12/58 10-1250 18-31,000 21 Anthracene 10/58 -10-1250 4-7,200 356 Fluoranthene 11/58 10-1250 6-12.000 357 Pyrene 11/58 10-1250 9-15,000 425 Benzo(a)anthracene* 8/58 10-1250 3-5,300 124 Chrysene* ' 10/58 10-1250 11-6,400 233 Benzo(b)fluoranthene* 9/58 10-1250 8-1,700 122 Benzo(k)fIuoranthene* 5/58 10-1250 11-4,300 222 8enzo(a)pyrene* 8/58 10-1250 17-3,300 214 Bis(2-ethylhexyl)phthatate 4/58 10-1250 6-920 95 Indenod,2,3-cd)pyrene* 5/58 10-1250 15-1300 94 Benzoic Acid 1/58 50-6250 10 Benzo(g,h,i)perylene 4/58 10-1250 15-1,000 83 Dibenz(a,h)anthracene* 2/58 10-1250 1-3 2 GROUNOUATER TABLE 4-22 (Continued)

~~ORGANIC CHEMICALS DETECTED IN GROUND UATER PINE STREET CANAL SITE, BURLINGTON. VERMONT~~

GEOMETRIC GEOMETRIC FEDERAL VERHONT PRIHARY CONTRACT RANGE OF MEAN OF HEAN OF LOCATION DRINKING CROUNDUATER NUMBER OF REQUIRED DETECTED OFF-SITE DETECTED OF UATER QUALITY CHEMICAL DETECTIONS/ QUANTITATION CONCEN. UELL MU-05 CONCEN. MAXIMUM STANDARDS STANDARDS CLASS CHEMICAL « OF SANPLES LIMIT (ug/L) (ug/L) (ug/L) CONCEN. (ug/L)' (ug/L)"

Pesticides/PCBs Hethoxyth(oi> 3/58 0.5-62.5 32-510 191 B-102B 400 PMCL 340/170 Endofidl-f 2/58 0.05-6.25 2.8-38 10 B-104B ...... Die|;drin 1/58 0.1-12.5 58 B-102B 2 LTHA 0.002/0.002 EndrhvKet 1/58 0.1-12.5 35 B-102B ...... alpha-Bl 1/58 0.05-6.25 6.6 B-104B ...... Endj^in 1/58 /\0.1-12.5 27 B-104B 2 TMCL • 4,4,-DOT 1/58/ ^ ^gU-12.5 14 B-104B ...... 4,4 -ODD 1/58/ ^ 0>sl2.5 1.8 MU-11B ......

~~' Federal Applicable or Relevant and Appropriate Require ted were selected tiased on availability, according to the following hierarchy:~~

HCL * Maximum Contaminant Level PHCL B Proposed Maximum Contaminant Level I H TMCL a Tentative Maximum Contaminant Level O NIPOUR c National Interim Primary Drinking Uater Regulat LTHA « Longer-Term Health Advisory (70 kg adult) L B Listed for regulation

~~Source: U.S. EPA Office of Drinking Uater, Drinking Uater Regulations and Health 1990~~

Vermont Primary Groundwater Quality Standards (Enforcement Standard/Preventive State of Vennont, Agency of Natural Resources, Department of Environmental Conservation, Chapter 12, Ground Uater Protection Rule'and 1989. 4.6.1 Volatile and Semivolatile Organic Analyses

In nineteen of the 51 wells sampled, no organic contamination was detected in the groundwater. These wells were mostly in the central portion of the site (B-110, W-1, W-2, W-6, W-7, B-103A, B 103B, B-106A, B-108, B-108A, MW-llA) or deep wells/^ip-OS, MW-llD, MW-03C, MW-04B, MW-09C). Two wells (MW-9A, UM-05/ a^t the north end f the site and one well in the wetlands (B-IOIA^^ 9lsc/dj<6 not have any detected organics.

Samples from eight wells in six well clusters (Hik^Sfi, MW-4A, MW-llB, MW-llC, B-102B, B-105, B-104A, B-104B) detected greater than 1000 ug/L total PAH concentrations in the groundwater. These eight wells are in the area of the fOTsa^r gas plant, wetlands and southern extent of the canal and \> define tfte--âjor groundwater organic contamination plume. The rW»aîmg/-a3/^wells had lesser amounts of organic contamination Veteaxed. The vertical groundwater contamination pattern is similar to the contamination pattern discussed in the section on soilîn that contamination concentrations increase from the surficial fill to the underlying peat, where contaminanXcohfentrations are greatest, and then decrease in the lower.

The most frequen^l^W detected volatile organics in groundwater samples were BTEXs, det^«tea\in approximately 4 0% of the wells. Ten other volatiles were detfe^ed in 5% of the wells or less. Two of these volatiles can be eliminated from consideration because they are below federal/state standards. Chloroform, detected five times, W21S eliminated because its highest detection (7 ug/l) was well below/the MCL\)f 100 ug/l. 1,2-Dichloroethene (total) was elimin44^aiaecausa tne one detection of 9 ug/l was below Vermont standardsNaf 3^/ug/1. Acetone was detected in both-background

4-106 wells (MW-5A, 160 ug/l; MW-5B, 250 ug/l) and in three other w^ B-IOIB in the wetlands (11 ug/l); MW-4A in the gas plant arj ug/l); and MW-7C behind the Maltex building (12 ug/l). chloride was detected in three wells: B-IOIB, in the wetlands ug/l); MW-ilB, by the southern barge slip (250 ug/l); and in MW-4A in the gas plant area (530 ug/l). All these concentrations were below the Vermont standard of 5 ug/l. Carbon/^îsulfide was detected only twice: MW-7A, behind the Maltex b^ (2 ug/l); and B-102B, by the southem barge slip (26 ug^ e are no standards for 2-3 hexanone, detected three -lie (280 ug/l); and the two background wells, MW-5A (21 ug, MW-5B (10 ug/l). 2-butanone, detected only in well B-102B by he/southem barge slip at 25 ug/l, was well below the Vermont Standard of 170 ug/l. Styrene was detected in three wells: B-104A (180 ug/l) and B-104B (40 ug/l), both in the southe;?nêtlands area; and MW-4A in the gas plant area (440 ug/l). All e of 5 ug/l, the rest are above the Vermont Preventive Action Limit of 0.5 ug/l. Vinyl chloride was detected in/'i^^Ôvwells: MW-IA, east of GE (43 ug/l); and MW-2A (1100 ug/l) ./Bptti o^these concentrations are above the MCL (2.0 ug/l). Vinyy^ chIoride"^4g a decomposition product of trichloroethene, anofcl^rVontamiha^(t found in the GE wells.

Of the above-listecK^^^olatiles, vinyl chloride and trichloroethene are associated with operations at GE. The other volatiles' are in wells associated with the gas plant/canal complex except for^eliMW-7 behind the Maltex building and MW-5A and B, the two jiSf^^sit^veXls to the south.

4-107 Figure 4-28, 4-29, 4-30, and 4-31 are contour maps for^ BTEX concentrations. These figures demonstrate the fact tt concentrations in groundwater increase with depth dov clay/silt layer just below the peat layer after which they begin' to decrease.

As stated earlier, the highest BTEX concentr n in the fill is in well UM-1 (benzene 830 ug/l, and ethyl 0 ug/l) at the north end of the site. In this one ar ^hest BTEX concentrations are in the near surface soils believed to be related to a fuel oil spill in 1986. Six other completed in the fill have BTEX concentrations: UM-3 (27 ug/l ^^^^Xene) j MW 7A (3 ug/l toluene); B-IOIB (3 ug/l toluene); MW-2A (6 ug/l benzene, 2 ug/l ethyl benzene and 1 ug/l toluene); MW-lA (1 ug/l benzene, 4 ug/l ethyl benzene, 2 ucf7l~-«iilene) ; and MW-7A (3 ug/l toluene) . Only those wells enolosjpd^ intsAtours have BTEX concentrations above the federal/sta

The highest concentration of BTfiX \3640 ug/l) in wells screened in the peat was in well B-104B (8©0 ug/l benzene, 670 ug/l toluene, 1600 ug/l ethyl benzene, 510 ug/l xylenes). Seven other wells screened in the p BTEX concentrations: MW-7B (4 ug/l each of BTX) ; MW-11 xylenes) ; well 105 (500 ug/l benzene, 380 ug/l e ug/l xylenes); MW-3A (16 ug/l benzene, 39 ug/l tolu ug/l "ethyl benzene, 150 ug/l xylene); 107A (39 ug/l benzene); ug/l toluene); and B-109B (2 ug/l toluene). As can be seen in gure 4-29, a BTEX contaminant plume shape has developed similar in appearance to the contaminant contours for -subsurface soils.

~~4-108 N illl i § § g § § § § g I § •0 i i §§§§§§§§§§s MLSUnNVmECT~~

~~SCALE (FEET) 100 200 300 400~~

~~• PEER WELLS~~

~~^ PREVIOUS WELLS~~

~~(WELLS SCREENED IN FILL) FIG. 4-28 PINE STREET CANAL SITE~~

~~4-109 i i i iiiS§l§§§Sg§ § I I I I II I I I I~~

~~SCALE (FEET) 100 200 300 400 3~~

~~• PEER WELLS~~

~~^ PREVIOUS WELLS~~

~~LAKE CHAMPLAJN~~

~~(WELLS SCREENED IN PEAT) FIG. 4-29 PINE STREET CANAL SITE~~

~~4-110 N S S I S g i i § § g 8 S S 8 g S 8 s § s s s ssssssssssss AauMNSTnOT I I I I I I I I I I I I I I I I I~~

~~SCA1£(FEET) 100 200 300 400~~

~~• PEER WELLS ^PREVIOUS WELLS CD 1£1'~~

~~LAKE CHAMPLAIN~~

~~BTEX (WELLS^E^ED ABOVE 40 FEET IN LOWER SILT/CLAY) ^^^^^ 1 FIG. 4-30 PINE STREET CANAL SITE~~

~~4-111 N i I ! i i I I S 8 g 8 S g g g I 8 SSSSSSSSSSSSSSSSS tOLMumtmSr 0 II i I I. I I I I I 1 I I I I I I SCAL£(FEET) 100 200 300 400~~

~~• PEER WELLS~~

~~^ PREVIOUS WELLS~~

~~LAKE CHAMPLAIN~~

~~BTEX (WELLS SCREENED BELOW 40 FEET IN LOWER SILT/CL^Y) FIG. 4-31 PINE STREET CANAL SITE~~

4-112 - The highest concentration of BTEX detected in a gro\md«^a^«^r X,^^ sample (7350 ug/l) was from a well screened in the silt/clay just^v ^ below the peat (MW-4A) located west of the former gas plant. This ^ ^ well had 3800 ug/l benzene, 2100 ug/l toluene, 690 ug/l ethyl benzene and 760 ug/l xylenes. BTEX was detected iivosnly one other well screened in the silt/clay above 40 feet in Qmp;ui.^ MW-3B had 3 ug/l toluene and 4 ug/l xylenes.

Groundwater contained volatile contaminants Dônlv two wells screened more than 40 feet below the ground surface .^sêê wells are MW-IB (next to GE, screened from 35 to 50 feet) where ethyl benzene was detected at 2 ug/l, and MW-7D (behind the Maltex building parking lot, screened from/WLô 90 feet), where toluene was detected at 3 ug/l.

Semivolatile compounds were detedted' i/i twenty-one of the 51 wells sampled. As stated previously, elgnt of these wells have total PAH concentrations greater than 1(><^ ug/l. There are no water standards for the PAHs. Seven PAHs do have proposed MCLs in the range of 0.1 to 0.4 far under the concentrations detected in the plume at this r other semivolatiles beside PAHs were detected in gr s. Dibenzofuran was detected in four wells, a! ith large (>1000 ug/l) PAH concentrations: MW-3A, ant area (100 ug/l); MW-llB, middle of canal (540 ug/l); B-104B> th end of wetlands (140 ug/l); MW 4A, gas plant area (23 ug/l). 4-methyl phenol was detected in three wells: MW-llA (6 ug/l); MW-IA, east of GE (19 ug/l); and MW 9A, north^^end offsite between the turning basin and Lake Champlain (6 ug/l)y/ ^\These were all shallow wells. Bis(2 ethylhfe^ry^thalate] was detected in four wells: MW-5B, off-site well (6 u5/l)>sMW^4W, gas plant area (150 ug/l); MW-3C, gas plant area (920 ug/l) ; X"*^ MW-9C, between turning basin and lake (100

~~4-113 ug/l). Benzoic acid was detected in well B-IOIB (in the we at 10 ug/l.~~

Besides the eight wells with >1000 ug/l total PAH, three wells had lesser concentrations of PAHs: well 107A, north of the Burlington Electric Department (5 ug/l naphthale MW-4B, gas plant area (9 ug/l naphthalene); and MW-3B, in ant area (1 ug/l acenaphthalene), For the eight well the PAH contaminant plume, total PAH concentrations incre pm the fill to the peat before beginning to decrease in t: erlying clay/silt. This is in contrast to the BTEX concentrati6ns that were greatest just below the peat. This is probably because of the greater solubility and mobility of BTEXs in groundwater. Figure 4-32 is a contour map of total RAHtonQentrations for wells screened in the fill. Five wells scr^^isd inthe fill detected PAHs, four of the wells were at the northNfnd/^^^he site, (NOTE: Values for total PAH concentrations at \he morth end of the site are from a previous investigation in 1986\an'^ should be used with caution.) Total PAH concentrations for wells screened in t^be fill were: UM-1, 81 ug/l; UM-2,^5 ug/l; and UM-3, 96 ug/l.

For wells screenc i^, the highest concentration of total PAHs was detect ^r from well B-104B at 231,500 ug/l. This well is at end of the wetlands and had about three feet of Dense Non-Ac Phase Liquid (DNAPL) in the bottom of the well when sampled. The ill was resampled after bailing and purging. A total PAH concentration of 112 ug/l was detected in the second samp . other wells had large PAH concentrations: MW IIB, 48,23<> L02F, first sample, 37,940 ug/l, second sample, 757 ug/2/i ^102B, Xirfet sample, 28,980 ug/l, second sample, 83,780 ug/l; and^MWHA, 19,285 ug/l. Figure 4-33 is the total PAH

~~4-114 "^ N Il!iiil88g8g8gggg sssssssssssssssss tojaumwrmer 0 I I I I I I I I I I I I I I I I I~~

~~SCALE (FEET) 100 200 300 400~~

~~• PEER WELLS~~

~~^ PREVIOUS WELLS~~

~~LAKE CHAMPLAIN~~

~~(CONCENTRATIONS IN PPB) l>Kt»IOC»Vt~~

~~TOTAbPAH'Sb ^ S (WELLS SCREENED IN FILL) FIG. 4-32 PINE STREET CANAL SITE~~

~~4-115 N N ! i i!!! 18 g g g 8 5 g g s g sssssssssssssssss •OLSUMSTnCIT 0 I 1 I I I .1 I I I I I I I I I I~~

~~SCALE (FEET) 100 200 300 400~~

~~• PEER WELLS crv^ ^ PREVIOUS WELLS~~

~~LAKE CHAMPLAIN~~

~~TO)T)WJ^AHT ' S (WELLS SCREENED IN PEAT) FIG. 4-33 PINE STREET CANAL SITE~~

~~4-116 concentration contour map for wells screened in the peat. T ug/l contour is basically the outline of the groundwater contaminant plume.~~

Only two wells screened down to a depth of forty feet (Figure 4-34) had PAHs detected in the silty clay below th^ eat. MW-4A, just west of the gas plant, was screened from 2 3^5 feet and detected 7250 ug/l of total PAH. MW-3B in the area was screened fron 28 to 38 feet and detec ug/l of acenaphthylene. No PAHs were detected in any well ned below 40 feet from the surface (Figure 4-35).

Figures 4-36, 4-37, 4-38 and 4-39 are concentration contour maps for carcinogenic PAHs in the different horizons. The contours are similar to those for total PAH^ for tK^~-re^pective horizons; however, they are orders of magnitude

Eight pesticides were detected in fourVells. All four wells are within the organic contaminant plume b^jmdary. Well B-104B at the south end of the wetlands detected five pesticides: alpha-BHC, 7 ug/l; Endosulfan I, 38 Endrin, 27 ug/l; 4,4*-DDT, 14 ug/l; and Methoxychlor, 430 1 B-104A in the same well cluster detected two pestici I, 3 ug/l; and Methoxychlor, 32 ug/l. Dieldrin xychlor (510 ug/l) and Endrin Ketone (35 ug/l) were ed in well B-102B near the former southern barge slip. Well IB just north of B-102B detected 4,4'-DDD at 1.8 ug/l.

~~4-117 S8|gillg8g8Sggggg SSSSSSSSSSSSSSSSS~~

~~SCALE (FEET) LJ p. 100 200 300 400~~

~~• PEER WELLS~~

~~^PREVIOUS WELLS~~

~~LAKE CHAMPLAIN~~

~~X"^/ TOTAL PAH'S (WELLS SCREENED ABOVE 40 FEET IN LOWER SILT/CLAY) FIG. 4-34 PINE STREET CANAL SITE~~

~~4-118 lilMllgggssgggig SSSSSSSSSSSSSSSSS I I i I I I i I i I I I I I i i I~~

~~SCALE (FEET) a 100 200 300 400 D~~

~~• PEER WELLS~~

~~^ PREVIOUS WELLS~~

~~: CHAMPLAIN~~

~~X^^ TOfAt^PAH'S (WELLS SCREENED BELOW 40 FEET IN LOWER SILT/CLAY)^ FIG. 4-35 PINE STREET CANAL SITE~~

~~4-119 li!iBlg88l8ggggg8 SSSSSSSSSSSSSSSSS i I I I I I I t I I I I I I I I 1~~

~~SCAL£(FEET) 100 200 300 400~~

~~• PEER WELLS~~

~~-*- PREVIOUS WELLS CD~~

~~LAKE CHAMPLAIN~~

~~CARCINOGENIC PAH'S (WELLS SCREENED IN FILL) FIG. 4-36 PINE STREET CANAL SITE~~

~~4-120 N n ! g ' (T\ S S 8 S~~

~~SCALE (FEET) 100 200 300 400~~

~~CARCINOC PAH'S (WELLS SCREENED IN PEAT) FIG. 4-37 PINE STREET CANAL SITE~~

~~4-121 N I I § g g I I g g g g 8 g g g g 8 S s s s s s s sssssssss s WJUWNSTWItT 0 I I I I I .1 t I I I I I I I I I I~~

~~SCALE (FEET) B too 200 300 400~~

~~• PEER WELLS~~

~~^ PREVIOUS WELLS~~

~~LAKE CHAMPLAIN~~

~~(CONCENTRATIONS IN PPB) Mk~~

~~CARCINOG^Et^ PAH'S (WELLS SCREENED ABOVE 40 FEET IN LOWER SILT/CLAY) FIG. 4-38 PINE STREET CANAL SITE~~

~~4-122 . N I 8 § § i iigggggggggg S s s s s sssssssssss s nukMianvrr 0 Mill. I I I I I I I 1 1 I I I SCALE (F ^ 100 200 300 400~~

~~• PEER WELLS~~

~~^ PREVIOUS WELLS~~

~~LAKE CHAMPLAJN~~

~~(CONCENTRATIONS IN PPB)~~

~~CARC^^OfeNIC PAH'S (WELLS SCREENED BELOW ^AQ FEET IN LOWER SILT/CLAY) FIG. 4-39 PINE STREET CANAL SITE~~

~~4-123 Summary~~

The major BTEX and PAH groundwater contamination plvunes overlie virtually the same area. This plume is "L" shaped and encloses the former gas plant property, the wetlands and the southem extension of the canal. In a vertical pijcSfê, the BTEX contamination plume has percolated into the top^ horizon underlying the peat while the PAH plume^ peat layer. This would be expected because solubility of the BTEX and because of the sorptive qu^ peat and PAH. An analysis of the individual PAH groundwater samples shows that 2-ring PAHs (naphthalene and 2 methylnaphthalene) usually make up approximately 50% of the total PAH concentration value. Five and îjT'tîig^PAHs (Indeno (1,2,3 cd) pyrene and Dibenzo (a, h)antnrsid^n€^l normally make up approximately 2 percent of total PAH conc^tr4^ron values (Figure 4-40). This is due in a large part to^the/insolubilities of the larger ring PAHs. This ratio could have sian^ficant impact on such factors as biodegradability (2-ring PAHs degrade easier than 6-ring PAHs) and total carcinogenic PAH concentrations (carcinogenic PAHs tend to have more rinos). j^ln analysis of groundwater samples failed to reveal a "front/wave'^-dl^smore mobile 2- and 3-ring PAHs. The ratio of 2- to

~~4.6.2 Inorganic Analyses~~

Occurr f inorganics in groundwater samples were widely variable kfei centration and frequency of detection. Table 4-23 pi;«seT ary of inorganics detected, frequency of detectio ertinent data. Groundwater data from two wells insta ite, to the south of the site, were used to

~~4-124 18000 ~~

~~NAPHTHALENE~~

~~16000 ~~

~~14000 ~~

~~12000 2-METHYLNAPHTHALENE~~

~~a. 10000 ~~

~~8000 ~~

~~6000 PHENANTHRENE~~

~~4000 CENAPHTHENE~~

~~m PYRENE 2000 t i T 1 - T 2 3 4 6 6 NUMBER OF BENZENE RINGS~~

~~TYPICAL DISTRIBUTION OF PAH'S IN GROUND WATER SAMPLES FIG. 4-40 PINE STREET CANAL SITE~~

~~4-125 CROUNDUATEIt TABLE 4-ZS~~

~~INORGANIC CNENICAIS DETECTED IN GROUND UATER PINE STREET CANAL SITE, 8URLINGT0N, VERMONT~~

GEOMETRIC GEOMETRIC FEDERAL VERMONT PR(MART CONTRACT RANGE OF MEAN OF MEAN OF LOCATION DRINKING GROUNOUATER NUMBER OF REQUIRED DETECTED OFF-SITE DETECTED OF UATER OUALITT CHEMICAL DETECTIONS/ QUANTITATION CONCENCEN. WELLS MU-05 CONCEN. NAXIHUN STANDARDS STANDARDS CLASS CHEMICAL 1 or SAMPLES LIMIT

Inorganics AluiiiniM 55/55 200 77-1,100,000 11.451 50066 MU-2B ... • M* Antimony 17/55 60 13.9-400 36 30.2 MU-2B 10/5 TMa ••« Arsenic / 52/55 10 2.4-93.4 21.1 32 V-4 50 NIPOUR 50/25 Bariu* / 55/55 200 32.1-2,970 201 353 MW-2B 5000 PMCL 1000/500 Beryl t Itai / 11/55 5 1.5-24.8 3.6 3.9 HU-2B 1 TMa —. Cadmiua 2/55 / . 5 13.9-41.0 23.9 HU-IA s PMa 5.0/2.5 Calciua 55/55 y^fVU^k. 9,490-1,400,000 138,534 131,076 MU-BA —. ... Chromiua 4«/55 / 10^S . 6.7-1.900 53.7 87 MU-2B 100 PMa 50/25 Cobalt A6/55 \ 3.9-929 25.9 67 NU-2B ...... Copper / /v NU-2B ... 46/55 / / ^\ \ 4.9-1,940 50.0 105 1300 PMa Iron 55/55 / MW ) 116-2,160.000 55,482 135,950 MW-2fl ...... Lead 58 HU-2B 52/55 / /^^*- -y J 2.3-822 29.6 SPMa 20/10 Hagnesiua 55/55/ / 5>000 10,700-666,000 47,491 66.803 MU-2B ... *•• Manganese 55/55S v/ ]" y, 23.6-45,400 2,991 10.702 HU-2B ... • *• Mercury \ 0.20-9.7 MU-IA I 24/55 /.2 ] 0.43 0.42 2 PMa 2.0/1.0 »-» Niclcel 50/55 7.1-2,540 58.4 145 MU-2B 100 TMa 350/175 to Potassiua 55/55 / V 2,320-151.000 11.134 19,208 HU-2B ...... Silver 2/55 V"\io» 5.5-37.2 14J ^ \ .. . MU-IA 50 NIPOUR 50/2S Sodiua 55/55 5,000 17.000-1,380,000 vsyx\ ^80,218 MU-5A —. • •• VaoMllua 52/55 50 2.6-1,530 y^'^^'>i / 102 MU-2B L • *• Zinc 20 9.8-4.710. NU-2B L • *• 5S/SS y^ liq / ^^ Cyanide 13/55 10 10.2-1,>

* Federal Applicable or Relevant and Approprlat* Rcqulre*Knt« (ARARt) (itted were Miected based(on |ivsll«bUlty, accordtno t^lwV^lMlna hierarchy:

M a • Haxlaaja Contaialnant Level PMCL • Proposed Maxlaua ContaMlnant Level TMCL a Tentative MaxlMua Contaailnant Level NIPDUR > National Interim Prinary Drinking Water Regulation LTHA • Longer-Tena Health Advisory (70 kg adult) L > Listed for regulation

~~Source: U.S. EPA Office of Drinking Water, Drinking Water Regulations and Health Advisories. April 1990~~

^ Venaont PriMry CroundMter Duality Standards (Enforccawnt Standard/Piheventlve Action Liiilt) froai State of Venaont, Agency of Natural Resources, Departaent of Envirormental Conservation, Chapter 12, Ground Uater Protection Rule and Strategy. 1989. establish background water quality and a geometric meapT f comparison to site specific groundwater concentrations.

Of the twenty-three metals and cyanide analyzed for in all groundwater samples, two metals, selenium and thallium were not detected in any samples. Sixteen metals were dete/Dted in almost every sample. Cadmium and cyanide were the only^two inorganics detected in on-site groundwater but not in the/oeiiwcgrou^d wells. Twelve of the inorganics detected were compared ra federal and state water cpaality standards and criteria.

If there were no accepted criteria or standards, individual concentrations of each substance were compared "to the geometric mean of the background samples to det^a:mine if concentrations were above background.

Antimony concentrations were detect^ JLn 17 wells. All 17 detections, with a range of 13.9 ug/l to\40X) ug/l, were above the Tentative MCL of 10 ug/l. However, one ^^undwater field blank had a concentration 23.9 ug/l of antimony. Nine groundwater samples (MW-3B, 47.7 ug/l 4A, 54.3 ug/l; MW-llD, 89.4 ug/l; MW 8A, 35.2 ug/l; MW-5B, 1; MW-llC, 72.5 ug/l; MW-IB, 30.8 ug/l; MW-2B, 400 ug/ 69 ug/l) had concentrations above this blank co 1 the wells were in the gas plant, southern canal ^rea except MW-5B, off site to the south and MW-8A, a bedrock' on the western boundary of the site. Well MW-2B had the largest concentration of antimony at 400 ug/l. No vertical contamination pattern was evit3ent.

Ars ations were detected in 52 wells. Fourteen groundw had concentrations above the 50 ug/l MCL ranging 1/1 (MW-3B) to 93.4 ug/l (W-4). Wells MW-3B (50.2 ug/l). (84.5 ug/l), B-IOIA (55.8 ug/l), MW-llB (88.0

4-127 ug/l) and MW-llc (52.3 ug/l) are all in the gas plant/cana wells MW-IB (64.9 ug/l), MW-2B (50.3 ug/1), B-104A (85 u B-104B (86.2 ug/l) are on or near GE property; W-4 (94.4 ug/l), B 106A (69.9 ug/l), W-7 (59.8 ug/l) are all in the central portion of the site; UM-3 (56.8 ug/l) and MW-9B (53.6 ug/l) are at the north end of the site and MW-5B (71 ug/l) is off sit4 jfeo the south. These wells are all shallow wells.

Barium was detected in all wells but onlyvone /groundwater sample was above the Vermont Primary Groundwater Qua>45ty^Standards Enforcement level of 1,000 ug/l, MW-2B (GE) detected 2/Mjo ug/l of barium. The level was not above the proposed EPA MCL of 5,000 ug/l.

All of the eight detections were above the Tentative MCL of 1.0 ug/l. Wells MW /I), MW-llD (8.6 ug/l), MW-4A (3.4 ug/l), and MW-3A ( g/1) are in the gas plant/canal area; wells MW-IB (2.2 ug/l), B (24.8 ug/l), B-104A (2.0 ug/l) and B-104B (6.6 ug/l) are on or ear GE property; wells W-4 (1.5 ug/l) and MW-7D (2.2 ug/l) are in the middle of the site; MW-lOA (2.2 ug/l) is aty^e nbrth end of the site; and MW-8A (2.2 ug/l) is a bedrock well on ti^e^Tfe^ side of the site. No vertical pattern was evident.<;^ 'raf }{igK^^ pfencentrations were in the gas plant/canal/ GE area.

Cadmium was detected twi^«^ and both concentrations were above the Vermont Standard and Proposed MCL of 5.0 ug/l. Well MW-2A, on GE property^^--det^cted 13.9 ug/l of cadmium and well MW-IA, east of GE, detected,--4i ug;

~~Chix^mivim, concjenurations were above the Vermont Standard and MCL of 50 \ig/l 1^1^ wells. Wells MW-IA (1,160 ug/l) ; MW-IB (244 ug/l), MW-2A CS9.y ug/l), MW-2B (89.8 ug/lg), B-104A (63.2 ug/l)~~

4-128 and B-104B (172 ug/l) are on or near GE property; wells MW-11 ug/l), MW-llD (576 ug/l), MW-4A (292 ug/l), MW-4B (87.4 ugy^ 3A (93.4 ug/l), MW-3B (161 ug/1), MW-3C (59.8 ug/l) are in € plant/canal area; wells W-7 (71.5 ug/l), B-108A (60.9 ug/l), W-4 (89.5 ug/l) and MW-7D (107 ug/l) are in the central part of the site; MW-8A (288 ug/l) is the deep well to the west,/and MW-5B (311 ug/l) is the off site well to the south. No vert&cyl contaminant pattern was evident.

~~Only one well, MW-2B, had a copper concentr above the proposed MCL of 1,300 ug/l. This well, on GE pro had a copper concentration of 1,940 ug/l.~~

Lead was detected in all but fou groundwater samples (UM-4, MW-9B, W-6, B-102B). Nineteen we^l i^ections above the Vermont Standard of 20 ug/l. These IS are from deep and shallow wells throughout the and exhibited no concentration patterns either areally -tically.

~~There was only one detection of mercury above the PMCL of 2.0 ug/l. This was from MW-Wr't9v.7 ug/l), east of GE property.~~

~~Nickel was dete ,above the Vermont Standard of 350 ug/l: MW-5B (3 te to the south; MW-llC (691 ug/l) and MW-llD (721 ug r the canal; and MW-2B (2,540 ug/l) on GE property.~~

~~Silver was detected twice, but neither detection was above the MCL of 50~~

~~ted four times above the Vermont Standard of ells are in the gas plant/canal area: MW-4A~~

~~4-129 (250 ug/l), MW-llC (336 ug/1), Well 105 (860 ug/l) and 104By(l^ ug/l), these are all shallow wells.~~

Since there are no accepted groundwater guality standards for the trace metals, aluminum, calcium, cobalt, iron, magnesium, manganese, potassiua, sodiiin, vanadium and zinc, a/Value of twice the respective geometric mean of concentration yal;aes>^from wells MW-5A and MW-5B was used to determine which Qon^ntra)£lons were above background for the individual metals.

Aluminum was detected seven times above the back^sp)Zhd level of 100,000 ug/l. Wells MW-4A (144,000 ug/1), MW-llC (273,000 ug/1) and MW-llD (340,000 ug/l) are in the gas plant/canal area; MW-IB (132,000 ug/l) and MW-2B (l,100,00'0-->4;g/l) are on or near GE property; MW-8A (129,000 ug/l) is -wie ^d^ep^^eilto the west; and MW-5B is an off site well to the stouth.y' The^ wells are both shallow and deep but all are at the so^h end of the site.

Calcium was detected six times above\me background level of 260,000 ug/l. Wells W-2 (280,000 ug/l) and W-4 (451,000 ug/l) are in the middle of the /^It^ MW-4A (480,000 ug/l) and MWA-llD (759,000 ug/l) are in/t)

~~Cobalt was detectedxourNtiwes above the background level of 130 ug/l. Wells MW-llC (259N^1) , MW-llD (281 ug/l), canal area; MW-5B (155 ug/l), off site well; and MW-2B (929 ug/l) GE property.~~

Iron cted five times above the background level of 270,000 MW-llC (483,000 ug/l), MW-llD (574,000 ug/1), canal ,160,000 ug/l) and B-104B (372,000 ug/l), GE property; '(306,000 ug/l), off site to the south. These wells are bot low and deep in the southern third of the site.

~~4-130 Magnesium was detected three times above the backgrou of 130,000 ug/l. W-4 (203,000 ug/l), in the middle of site; MW llD (306,000 ug/l), by the canal; and MW-2B (660,000 ug/l), on GE property.~~

~~Manganese was detected only once above the nd level of 21,000 ug/l. This was in well MW-2B ( on GE property.~~

Potassium was detected six times above the backgfbuhd level of 38,000 ug/l. MW-llC (48,900 ug/1), MW-llD (57,500 ug/l) and MW 4A (45,900 ug/l), in the gas plant/canal area; MW-2A (108,000 ug/l) and MW-2B (151,000 ug/l), on GE prop^fftyT-aiid MW-5B (43,000 ug/l), off site well to the south.

Sodium was detected four times aboVe t^e background level of 560,000 ug/l. Wells W-2 (986,000 ug/l) ahd W-4 (643,000 ug/l), in the middle of site; UM-5 (1,090,000 ug/l) ,^at north end of site; and MW-5A (1,090,000 ug/l)jOff site. All these wells are shallow wells near areas that receivk snow melting materials during the winter.

Vanadium was detected eight times above the background level of 200 ug/l. Wells MW-IB rs^lbq/l) and MW-2B (1,530 ug/l), B-104B (277 ug/l), on or near GE property; MW-llC (465 ug/l), MW-llD (585 ug/l), MW74A (307 ug/l), in the gas plant/canal area; MW-8A (396 ug/l), a de^p-we^l to the west; and MW-5B (285 ug/l), an off site well.

~~four times above the background level of 740 (1,210 ug/l) and MW-llD (1,910 ug/l), by the~~

~~4-131 canal; MW-2B (4,710 ug/l), on GE property; and MW-5B (911 an off site well.~~

There does not appear to be a general pattem in the vertical distribution of inorganic contaminants, although the higher concentration values were usually detected in theysh^llower wells except for calcium, in MW-8A. MW-8A is a bedrockywejd irtslimestone (calcium carbonate).

Areally, a group of wells are consistently abov^ o&ckground or groundwater guality standards for many trace metals: TJW-3B (At, Ar, Ba, Cr) gas plant area; MW-4A (At, Ar, Be, Cr, Cyanide, Al, Ca, K, Vd) gas plant area; MW-llC (At, Ar, Be, Cr, Ni, Cyanide, Al, Co, Fe, K, Vd, 2n) near canal; MW-11 , Cr, Ni, Al, Ca, Co, Pe, Mg, K, Vd, Zn) near canal; MW-1B\( r, Al, Vd) east of GE; MW-2B (At, Ar, Ba, B*e, Cr, Cu, Co, Fe, Mg, Mn, K, Vd, Zn) on GE property; 104B (At, Cr, Cyanide, Fe, Vd) on GE property; MW-5B (At, Cr, Ni, Al, C , K Vd, Zn) off site well to south; and MW-8A (At, Be, Cr, Al, a Vd) bedrock well at west of site.

Above acceptable nide were found only in the gas plant area. Wells and MW-IA and MW-IB contained the only detected or a ^ceptable limits of cadmium, mercury, barium and copper. Well ,had the highest frequency (16 out of 22) of high concentrations

The de $n of cadmium only on or around GE property, the highest maximum concentrations of trace metals on GE propert detection of above background/standards concent be metals in a well south of the site suggest that the gasification plant may not be the sole source of contaminati the site.

~~4-132 4.7 Biota~~

Eighteen samples of fish caught during gillnetting activities were analyzed, nine from the site and nine from the control area, the La Platte River Marsh. The following were analvzed for each site: golden shiner (Notemigonus crvsoleucas) ow perch fPerca flavescens) whole body, fillet, and r after filleting; northern pike fEsox lucius) fillet Inder; and chain pickerel fEsox nicer) whole body. Results analyses for volatiles, semi-volatiles, pesticides/PCBs and ics are presented in Table 4-24, 4-25 and 4-26. Samples 01 throug'h 06 were from the site, samples 07 through 12 were from the control area.

Methylene chloride was found i ^ner guts only (690 ug/kg). Acetone was found in all t on-site perch fillet. The highest acetone conce (1200 ug/kg) was detected in shiner fillet. Carbon dis i^de was detected in 7 samples and in all species except pike; s of these samples were from the control area. The highest concentrations of 2-butanone were in gut samples fro; site (pike, 770 ug/kg) and control area (perch, 1000 ug/ xylenes, and benzene were detected more freque tiy higher concentrations in control area samples'^ , styrene, and chlorobenzene were detected only in ofi^ shiner samples.

Semi-volatiles were detected in both on-site and control area samples. ' The compounds, and sample with highest concentration, include: /^^^meEhyphenol (420 ug/kg in on-site shiner fillet); di-n-butyl tjfitliJtlatk (1700 ug/kg in control area perch); bis-(2 ethylhexylK-Phtharata (1100 ug/kg in on-site shiner guts) ; and benzoic ab4dcA600/ug/kg in on-site shiner guts, an order of

~~4-133 TABLE 4-24 FISH TISSUE ANALYSIS DATA (ug/kg)'~~

Golden Shiner fNotemigonus crvsoleucas) MsL Gut? _ Whole Bodv Compound 01 07 OIG 07GG/ N 02 08 Volatiles Methylene chloride 690BE' Acetone 1200BE 260E 120B Carbon disulfide 2J 7 3J 2-butanoae 44B Toluene IJ 2J Ethyl benzene IJ Styrene IJ Total Xylenes 3J 2J Benzene Chlorobenzene Semi-Volatiles 4-methyl phenol 420J 460 Benzoic Acid 2100 J 1400J 88J Naphthalene 3900 3200 Di-n-Butyl phthalate 480BJ 300BJ 120BJ Bis-(2-ethylhexyl) phthalate 370BJ 740B 400BJ 380B Benzaldehyde 2600J 6100J Pesticides/PCBs 4,4'-DDE 29X 4,4'-DDD

^ Samples 01-06 from the site; 07-12 ft^ >controI area ^ B - analyte found in blank, but sample concentration is at least an order of magnitude higher. £ - calibration exceeds calibration range of GC/MS instrument. X - concentration < but > 1/2 mass corrected CRQL.

~~4-134 TABLE 4-24 (Continued) nSH TISSUE ANALYSIS DATA (mg/kg)'~~

~~Golden Shiner fNotemigonus crvsoleucas) Whole Bodv 02 08~~

~~Aluminum Barium Calcium Chromium Copper Iron Lead Magnesium Manganese Mercury Potassium Selenium Silver Sodium Zinc Moisture Content^ Lipid Content^~~

~~' Samples 01-06 from the site; 07-^ from the control area ^ Unqualified data only, mg/ki ' Percentage~~

~~4-135 TABLE 4-25 nSH TISSUE ANALYSIS DATA (ug/kg)'~~

~~Yellow Perch fPerca flavescens)~~

_Eil£L Guts whpig Body 03 09 03G ^/ ^ ^ ^° Volatiles Methylene chloride Acetone nOBE^ 130B 230BE Carbon disulfide 7DJ 2-butanone 360E lOOOE Toluene 6DJ Ethyl benzene Styrene Total Xylenes 3J 3J 7DJ Benzene IJ 3DJ Chlorobenzene Semi-Volatiles Benzyl Alcohol 70J 4-methyl phenol 86J 89J 180 J Benzoic Acid 120 J 130J 240J Naphthalene Di-n-Butyl phthalate 300BJ M 260^ 880B 180BJ 1700B Bis-(2-ethylhexyl) phthalate 560B 550B 390BJ 710B 6S0B 520B Benzaldehyde 2800J 3700J 4900J 2900J 5900J Pentachlorophenol noj Pesticides/PCBs 4,4'-DDE -x^ 72 72 18X 52 4.4'-DDD J9X 27X

' Samples 01-06 from the site; 07-12 from the control area. ^ B - analyte found iii^ blank, but sample concentration is at least an order of magnitude higher. E - calibration^xceiasscalibration range of GC/MS instrument. X - Concenjfratijja-<.but\l/2 mass corrected CRQL.

~~4-136 TABLE 4-25 (Continued) FISH TISSUE ANALYSIS DATA (mg/kg)'~~

~~Yellow Perch fPerca flavescens)~~

MSL g«t8 „/ . ytiple Body 03 09 03G 09Ga/ y 04 10 Inorganics* Aluminum 16.3 Barium Calcium 45,300 52.600 7230 Chromium ij6 Copper ZO Iron 36.4 45.8 Lead Magnesium 1550 579 Manganese 13.1 5.1 Mercury .41 .52 Potassium 11,200 7390 Selenium SUver Sodium 3490 1650 Zinc 62 38.1 Moisture Content' 69.3 Lipid Content' 2.1

~~' Samples 01-06 from the site; 0 * Unqualified data only, mg/f ' Percentage~~

~~4-137 TABLE 4-26 FISH TISSUE ANALYSIS DATA (ug/kg)'~~

Northern Pike fEsox lucius) Chain Pickerel fEsox nieer) -EM. gytt Whole PPdY 05 11 06 12 Volatiles Methylene chloride Acetone 230BE 71 62B Carbon disulfide IJ 2-butanone Toluene IJ Ethyl benzene Styrene Total Xylenes IJ Benzene IJ Chlorobenzene Semi-Volatiles 4-methyl phenol Benzoic Acid 200J \ 1301/ 130J 210J Naphthalene Di-n-Butyl phthalate 21 OBJ 3200B l«mj\ llOBJ 230BJ 650B Bis-(2-ethylhexyl phthalate 440B 550B 280BJ 470B 380B 470B Benzaldehyde 630J Pesticides/PCBs \ 4,4'-DDE Aox) 25X 50 26X 4,4'-DDD 14X >

^ Samples 01-06 from the site; 07-1•12frb2 {f n 1 th^control area. ^ B - analyte found in blank, but sample concentration is at least an order of magnitude higher. £ - calibration exceeds calibration range of GC/MS instrument. X - Concentration is < but > 1/2 mass corrected CRQL.

~~4-138 TABLE 4-26 (Continued) nSH TISSUE ANALYSIS DATA (mg/kg)'~~

Northern Pike fEsox lufiius) Chain Pickerel fEsox niger) FUct Guts Whole Bodv 05 11 05G II Gz > 06 12 Inorganics*

Aluminum 713 Barium Calcium 12,700 38,300 17,600 Chromium Copper 2.0 4.5 Iron 43.1 145 Lead Magnesium 1050 1090 Manganese 5.2 10.7 Mercury 0.57 1.3 Potassium 11,700 11.700 Selenium Silver Sodium 2480 3230 Zinc 118 170 Moisture Content' 73.6 76.3 Lipid Content' 2.7 1.1

~~' Samples 01-06 from the site; 07 control area. ^ Unqualified data only, mg/r ' Percentage~~

~~4-139 magnitude higher than control samples). Pentachloro was detected only in one off-site perch sample.~~

The pesticide 4/4'-DDE was found in tissues of all species (but not all samples) both on-site and off-site, The highest concentration (72 ug/kg) was found in on-site and co: pi areaperch gut samples. Only on-site pike and perch samples tained 4,4* DDD. Interestingly, PCBs were not detected, y/ sample, Previous studies have found measurable concent f PCBs in canal fish and in perch (0.02 ppm) from Lake ain near Burlington (Langdon, et al, 1988).

For inorganics, selenium (2.1 mg/kg) and silver (1.1 mg/kg) were detected only in on-site shineass^^^ Aluminum (9 samples), barium (3 samples), chromium (11 samiples)r'"Tt«a^.^^(5 samples) and mercury (12 samples) were detected iivvl3ak;h^an4l^nd control area fish tissues. The highest concentration of/aluminum (713 mg/kg) was in on-site pickerel tissue. Barium W s detected only in shiner; chromium was found in all species^^cept pickerel. Four of five tissue samples containing lead were from on-site; the off- site perch fillet sampl tained an intermediate level 0.81 mg/kg. Mercury was fo ently in control fish tissue (8 of 9 control sampl ecies. This metal was found in less than half aken on-site (4 of 9) and concentrations were lowe

Table 4-27 summarizes fish contaminant data and provides ranges and sample with highest concentration for on-site and control area's^ ^n^site shiner tissues generally had the highest contaminaxu:/concentations, although similar, and occasionally slightli^' higher, \al|ues were found in control area samples. However, rhxee\yol«iti(les, one semi-volatile, one pesticide, and two inorganic^swere/detected only in tissues from canal fish:

~~4-140 TABLE 4-27 SUMMARY OF FIBH TISSUE ANALYSIS~~

~~On-site Tissue Samples (ug/Ko)' Off-Site Tissue Samples fug/Kg) Concentration Proportion Concentration Proportion Range of Detects MAX Range of Detects MAX~~

~~Volatile^~~

methy^en< 1/9 GIG acetoi 8/9 01 62-400 9/9 07G carbon ^tl^lfij 1/9 01 1-7 6/9 07,10 2-butanone 5/9 OSG 110-1000 3/9 096 toluene 3/9 OIG 1-6 4/9 10 total xylenes 2/9 01 1-7 5/9 10 benzene 1/9 OIG 1-3 3/9 10 styrene 1/9 01 ethyl benzene 2/9 01 ch1orobenzene 1/9 DIG I Semi-Volatiles Benzyl alcohol 70 1/9 10 4-methyl phenol 86-460 110-180 2/9 10 Benzoic Acid 130-4600 88-240 5/9 07 di-n-butyl phthalate 160-1600 110-3200 8/9 11 Bis-(2-ethylhexyl) phthalate 280-1100 380 8/9 07 Benzaldehyde 630-21,000 2600-5 4/9 10 Naphthalene 3200-12,000 Pentachlorophenol 1/9 96 Pesticides

4,4'-DDE 16-72 8/9 03G 20-72 6/9 4,4'-DDD 14-27 3/9 036 r Samples 01 and 07 shiner filet; 02 and 08 - shiner whole body; 03 and 09 - perch 05 and 11 - pike fillet; 06 and 12 - pickerel whole body? 6 - remainder of fish filleting. TABLE 4-27 (Continued) SUMMARY OP PISH TISSUE ANALYSIS

~~On-site Tissue Samples fmg/Kg)' Off-Site Tissue Samples fmg/Kg) Concentration Proportion Concentration Proportion Range of Detects MAX Range of Detects MAX~~

~~Inorganl~~

Aluraln 10.9-713 5/9 06 16.3-73.1 4/9 08 Bariu 27.1 1/9 02 23.2-24.9 2/9 08 Calcium 12,700-82,900 9/9 036 7230-105,000 9/9 076 Chromium 0.9-; 7/9 02 - 0.76-2.0 4/9 076 Copper 1.3y 8/9 01 1.5-4.8 7/9 08 Iron 17./4-< 9/9 01 27^-155 9/9 08 Lead 4/9 01 0.81 1/9 09 Magnesium 9/9 02 579-2820 9/9 076 Manganese 9/9 02 5.1-49.9 9/9 076 Mercury 4/9 05 0.35-1.3 8/9 12 Potassium 6850- 9/9 06 7390-13,000 9/9 11 I Selenium 1/9 02 (-» Silver 0.96-J 2/9 016,-^\ K> Sodium 1910-3490 9/9 03^^ 7 1650-339 9/9 076 Zinc 50.7-232 9/9 x^-vi / 38.1-170 9/9 12

Samples 01 and 07 shiner filet; 02 and OS'''^ sltlner irhole body; 03 and 09 - petch filet; 05 and 11 - pike fillet; 06 and 12 - pickerel wholf body; 6 - remainder of fish after filleting methylene chloride; styrene; ethyl benzene; chlorobe naphthalene; 4,4'-DDD; selenium; and silver. Benzyl alco! pentachlorophenol were detected in control area fish only.

It is significant that no bullhead were found to inhabit the canal. This species is known for its susceptibility to PAH contamination. Generally, fish richness was reduced^iiv^he canal compared with the control area.

~~4-143~~