EPA/ROD/R03-00/018 2000

EPA Superfund Record of Decision:

TOBYHANNA ARMY DEPOT EPA ID: PA5213820892 OU 04 TOBYHANNA, PA 09/19/2000 RECORD OF DECISION TOBYHANNA ARMY DEPOT

DECLARATION

SITE NAME AND LOCATION

Tobyhanna Army Depot Operable Unit #4 Coolbaugh Township Monroe County, CERCLIS ID#_ PA5213820892

STATEMENT OF BASIS AND PURPOSE

This Record of Decision (ROD) presents the selected remedial action for Operable Unit Four (OU-4) at the Tobyhanna Army Depot in Coolbaugh Township, Monroe County, Pennsylvania (the "Site"), chosen in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980, as amended, 42 U.S.C. §9601 et seg. and, to the extent practicable, the National Oil and Hazardous Substances Pollution Contingency Plan (NCP), 40 C.F.R. Part 300. This decision is based on the Administrative Record for this Site.

The Commonwealth of Pennsylvania Department of Environmental Protection (PADEP) concurs with the selected remedy. The concurrence letter from the Commonwealth is contained in the Site Administrative Record.

ASSESSMENT OF THE SITE

If not addressed by implementation of the remedy selected in this ROD, the site identified in this ROD may present an imminent and substantial endangerment to public health and welfare, or the environment.

DESCRIPTION OF THE SELECTED REMEDY

OU #4, also referred to as Area of Concern (AOC) #55, consists of a former range that was used during World Wars I and II. There is a potential that unexploded ordnance (UXO) is present at OU-4; the UXO presents a threat to public

1 health and safety. The objectives of the selected remedy for OU-4 are as follows: to restrict access to UXO areas by onsite personnel or trespassers; ensure that proper clearance procedures are followed if or when any portion of the area is to be developed by the Army in the future; restrict future uses of the land; and educate the public/employees on the dangers of coming into contact with UXO.

The selected remedy for OU-4 is the recommended alternative identified in the Proposed Remedial Action Plan dated June 24, 2000. That alternative is institutional controls. The components of this remedy include:

Physical Controls - Maintenance of the barbed wire fence and 40 signs posted around-the perimeter of OU-4.

Security Patrols/Monitoring - Increased security patrols to minimize the number of willful trespassers onto OU-4, especially during periods of increased pedestrian activity (e.g., hunting season).

UXO Support - Use of Explosives Ordnance Disposal (EOD) trained personnel to provide support in the case that any future intrusive activities by the Army take place within OU-4. This requirement will be incorporated into the base Master Plan.

Proprietary Controls - Deed restrictions on the land if it is ever transferred outside the government.

Public/Employee Education - Informing the public and Tobyhanna Army Depot (TYAD) employees of the dangers of contact with potential UXO.

Periodic Review - In accordance with CERCLA, a review at a minimum of every five years to determine the effectiveness of the remedy.

Previous response actions have been selected and/or implemented to address Operable Unit One, which consists of contaminated groundwater attributable to AOCs #4 and #7, Operable Unit Two, which consists of a former PCB transformer substation, and Operable Unit Three, which consists of two former hazardous waste storage buildings.

2 STATUTORY DETERMINATIONS

The selected remedy is protective of human health and the environment, complies with Federal and State requirements that are applicable or relevant and appropriate to the remedial action, is cost-effective and utilizes permanent solutions to the maximum extent practicable. The remedy for OU-4 does not satisfy the statutory preference for treatment as a principal element of the remedy due to the cost-prohibitive nature and issues with implementability of treatment alternatives that would satisfy the statutory preference. The Army and EPA, with the concurrence of PADEP, believe that the selected remedy provides the best balance of trade-offs among the alternatives with respect to the response criteria.

3 RECORD OF DECISION

TABLE OF CONTENTS

SECTION PAGE I. SITE NAME, LOCATION, DESCRIPTION 7 II. SITE HISTORY 9 III. HIGHLIGHTS OF COMMUNITY 10 PARTICIPATION IV. SCOPE AND ROLE OF THIS RESPONSE 11 ACTION V. SUMMARY OF SITE CHARACTERISTICS/ EXTENT OF CONTAMINATION 12 VI. CURRENT AND POTENTIAL FUTURE LAND 15 USES VII. SUMMARY OF SITE RISKS 16 VIII. REMEDIAL ACTION OBJECTIVES 18 IX. DESCRIPTION OF ALTERNATIVES 19 X. COMPARATIVE ANALYSIS OF 24 ALTERNATIVES XI. PRINCIPAL THREAT WASTES 29 XII. SELECTED REMEDY 30 XIII. STATUTORY DETERMINATIONS 33 XIV. DOCUMENTATION OF SIGNIFICANT 35 CHANGES XV. RESPONSIVENESS SUMMARY 35

ATTACHMENTS NUMBE PAGE R 1 Glossary of Terms 38 2 Risk Assessment Procedures 40

4 FIGURES NUMBE PAGE R 1 Tobyhanna Army Depot Site 49 Location Map 2 Location of Radar Test Facility 50 3 Location of Fence Line 51 4 Surface Drainage Map 52 5 Firing Range Map 53

List of Acronyms and Abbreviations

AMC U.S. Army Materiel Command AOC Area of Concern ARARs Applicable or Relevant Appropriate Requirements Bgs Below Ground Surface Level CERCLA Comprehensive Environmental Response, Compensation, and Liability Act CFR Code of Federal Regulations DoD Department of Defense EE/CA Engineering Evaluation/Cost Analysis EMD Tobyhanna Army Depot Environmental Management Division EOD Explosive Ordnance Disposal FFA Federal Facility Agreement FUDS Formerly-Used Defense Site HE High Explosives HFA Human Factors Applications, Inc. HQDA Headquarters, Department of the Army NCP National Oil and Hazardous Substance Pollution Contingency Plan NFA No Further Action OE Ordnance and Explosives O&M Operation and Maintenance OU Operable Unit PCB Polychlorinated Biphenyls RAB Restoration Advisory Board RAC Risk Assessment Code ROD Record of Decision SARA Superfund Amendments and Reauthorization

5 Act of 1986 TBC To Be Considered TYAD Tobyhanna Army Depot USACE U.S. Army Corps of Engineers USEPA U.S. Environmental Protection Agency UXO Unexploded Ordnance

6 RECORD OF DECISION

TOBYHANNA ARMY DEPOT

DECISION SUMMARY

I. SITE NAME, LOCATION, AND DESCRIPTION

Tobyhanna Army Depot (TYAD) is located in Monroe County, Pennsylvania, approximately 15 miles southeast of Scranton, Pennsylvania, adjacent to the Village of Tobyhanna (Figure 1). The National Superfund electronic database identification number is PA5213820892.

TYAD was initially established as Camp Summerall when the United States purchased 33 square miles of land in northeastern Pennsylvania in 1909. The name of the installation, as well as its mission, has changed throughout the years. The area was used by the Army and National Guard for machine gun and field artillery training beginning in 1913, and later was renamed Tobyhanna Military Reservation. The reservation became an ambulance and regiment training center and an ordnance storage depot during World War I.

The installation was deactivated after World War I and remained inactive until 1932 (USATHAMA, 1980). However both regular Army and National Guard Field Artillery units trained at Tobyhanna during its supposedly deactivated period. From 1919 to 1932, it was the only site in Pennsylvania where live cannon fire was permitted. From 1932 to 1938, the Civilian Conservation Corps used the area as a camp. From 1938 to 1941, cadets from West Point used the area for field artillery training.

In 1942, the installation was reactivated as an Army/Air Force Service Unit Training Center. The area was also converted to a storage and supply area for gliders and other equipment of the Air Service Command in 1944. Tobyhanna continued to be used as an artillery range from 1942 to 1946 (USACE 1995). The installation was deactivated after World War II.

In 1949, the Commonwealth of Pennsylvania purchased approximately 21,000 acres from the United States War Assets Administration; from 1949 to 1951 that property was maintained

7 by the Pennsylvania Department of Forests and Waters and the Pennsylvania Game Commission. In 1952, approximately 1,293 acres were obtained by means of a quitclaim deed from the Commonwealth by the United States government for depot construction. The balance of the original 21,000-acre tract remained State-owned and today is largely State game lands and parks.

In 1953, the installation was designated and established as Tobyhanna Signal Depot, a Class II installation, with an assigned supply mission. In 1962, Tobyhanna Signal Depot was transferred to the Material Command (AMC). Since 1962, the installation has been used for a variety of purposes including the Department of Defense household goods movement and storage and maintenance of the Army's central file of motion pictures and distribution of audio-visual materials.

The current function of TYAD is as a communication- electronics maintenance and supply depot specializing in the design, fabrication, repair, and modification of a wide range of communications and electronics systems. These systems, which range in size from hand-held radios to satellite communications ground terminals, are associated with navigation, aircraft survivability, surveillance, and electronics warfare.

On July 14, 1989, the Tobyhanna Army Depot (TYAD) was proposed for inclusion to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) National Priorities List (NPL), and subsequently added to the final NPL on August 30, 1990. The Department of the Army (DA) has been granted the authority to be the lead agency at TYAD under Executive Order 12580 and CERCLA, as amended by the Superfund Amendments and Reauthorization Act of 1986 (SARA). The United States Environmental Protection Agency (EPA) and the Commonwealth of Pennsylvania have authority at TYAD as support agencies.

Description of Area of Concern #55, the Former Artillery Range

The former Tobyhanna Artillery Range comprises approximately 21,100 acres, consisting of firing points and impact areas. Currently, the former site is subdivided into Pennsylvania State Parks, Pennsylvania Game Commission land, Coolbaugh Township Municipal Park, and the Tobyhanna Army Depot. This Record of Decision only addresses AOC #55, which is a portion of the original range is approximately 400 acres in size, and is currently part of the depot. The remainder of the artillery

8 range is considered to be a Formerly Used Defense Site (FUDS) and is under the jurisdiction of the U.S. Army Corps of Engineers.

The U.S. Army and National Guard used the range for artillery practice and machine gun training from 1912 until 1949. AOC #55 mainly received 37 and 75MM ammunition fire from two firing points, one on the southwest end of the depot and the other on the northwest side of the depot.

II. SITE HISTORY

In April 1987, EPA performed a preliminary review and visual site inspection to identify potential Solid Waste Management Units (SWMUs) and other areas of potential concern at TYAD (EPA, 1987). This study identified 52 SWMUs, one of which was the unexploded ordnance area. The 1987 EPA Study recommended that no further action be taken due to the area's low potential for migration of any chemical contaminants into the air, soil, groundwater, or surface water. The 1987 EPA Study did not address any potential for exposure to the UXO from a safety perspective.

On July 14, 1989, Tobyhanna Army Depot was proposed for inclusion to the CERCLA National Priorities List (NPL) and subsequently added to the final NPL on August 30, 1990. The EPA Region III and the Department of the Army (DA) negotiated a comprehensive Federal Facility Agreement (FFA) which was signed by EPA on November 19, 1990, and became effective on January 19, 1991. The primary purpose of the FFA was to ensure that environmental impacts associated with past disposal activities at TYAD were thoroughly investigated, and appropriate CERCLA remedial action alternatives developed and implemented to protect human health and the environment. The FFA identified sixty-five (65) Areas of Concern (AOCs) within TYAD, one of which was listed as AOC 455, the “UXO area”.

From October to December 1998, the Army conducted removal activities to clear approximately 20 acres of land within AOC #55 for construction of a radar testing facility. The footprint of the radar testing facility and an area 100 feet around the facility footprint were cleared to a depth of four feet. The fence line and fence line footprint were also cleared to a depth of four feet. All other areas within the construction site were cleared to a depth of one foot. The radar testing facility site is shown on Figure 2.

9 In August 2000, TYAD completed a CERCLA removal action at AOC #55 that involved the installation of a barbed wire fence and warning signs around the perimeter of the entire UXO area. The purpose of this removal was to prevent trespassers and other unauthorized personnel from entering the UXO area and inadvertently coming into contact with any ordnance. The fence line is shown on Figure 2.

III. HIGHLIGHTS OF COMMUNITY PARTICIPATION

Since March 1995, the plans and results of ongoing CERCLA investigations and actions have been presented to the Restoration Advisory Board (RAB) established for TYAD. The RAB includes representatives of Coolbaugh Township, former TYAD employees, and other interested parties.

In accordance with sections 113 and 117 of CERCLA, 42 U.S.C. '' 9613 and 9617, the Army, in conjunction with EPA and the State, issued the Proposed Remedial Action Plan (PRAP) for OU-4 on July 24, 2000. This document is included in the Administrative Record file and was made available for public review at the following public repositories:

Coolbaugh Township Municipal Building 5500 Memorial Boulevard Tobyhanna, Pennsylvania 18466 Phone: (570) 894-8490 Hours: 8:00 a.m. to 4:30 p.m.

Tobyhanna Army Depot Public Affairs Office 11 Hap Arnold Boulevard, Building 11 Tobyhanna Pennsylvania 18466-5076 Phone: (570) 895-6552 Hours: 7:30 a.m. to 4:00 p.m.

Notice of availability of the PRAP document was published in The Pocono Record, a general circulation newspaper serving the Monroe County area, on June 24, 2000. A public comment period was held from June 24, 2000 to July 24, 2000. In addition, a public meeting was held on July 20, 2000, to present the PRAP for OU-4, to answer questions and to receive public comments. The public meeting minutes have been transcribed and a copy of the transcript is available to the public at the repositories. A Responsiveness Summary, included as part of

10 this ROD, has been prepared to respond to the significant comments, criticisms, and new relevant information received during the comment period. Upon signing the ROD, the Army will publish a notice of availability of this ROD in The Pocono Record, and place the ROD in the Administrative Record located in the repositories.

IV. SCOPE AND ROLE OF OPERABLE UNIT OR RESPONSE ACTION

As with many Superfund sites, the environmental issues at TYAD are complex. As a result, EPA, PADEP and the Army have categorized the work into five manageable operable units (OUs):

! Operable Unit 1 (OU-1): Areas A and B ! Operable Unit 2 (OU-2): Former PCB Transformer Area ! Operable Unit 3 (OU-3): Former Hazardous Waste Storage Areas ! Operable Unit 4 (OU-4): UXO Area ! Operable Unit 5 (OU-5): Inactive Landfill

A remedy was selected for OU-1 in a ROD signed on September 30, 1997. OU-1 consists of a former burning area (Area A) and a former hazardous waste staging area (Area B) that were determined to be the sources of a VOC-contaminated groundwater plume that had migrated offsite and contaminated several private wells. Since the discovery of this plume, the Army has connected the affected residences to the depot water supply and has removed the source of contamination at Area B. The remedy selected for OU-1 consists of natural attenuation, long-term monitoring, and institutional controls. TYAD monitors the groundwater on a semi-annual basis, and VOC concentrations continue to decrease.

Remedies for OU-2 and OU-3 have also been selected. The selected remedy for OU-2, the two former hazardous waste storage buildings, was "No Further Action". This remedy was selected because the two hazardous waste storage buildings were remediated under a RCRA closure action and residual contaminants in soils were below risk-based levels. The selected remedy for OU-3, the former PCB transformer building, was "No Further Action". Soils contaminated with PCBs were removed from the site and residual levels of PCBs were below risk-based concentrations.

11 OU-4, the subject of this ROD, addresses the on-post area known to contain UXO. Exposure to UXO at this site could result in an imminent threat to human health or welfare and the environment if not remediated. In June 2000, TYAD performed a CERCLA removal action at AOC #55 that involved the installation of a barbed wire fence and warning signs around the perimeter of the UXO area. The purpose of this removal action was to prevent trespassers and other unauthorized personnel from entering the UXO area and inadvertently coming into contact with any ordnance. OU-5, the inactive landfill, contains a small VOC-contaminated groundwater plume. This OU is presently being evaluated; a final decision is expected this year. OU-5 will be the final action for the entire CERCLA site.

In addition to the above OUs, TYAD, EPA and PADEP have also completed investigation at 53 additional AOCs and have determined that none of them require further action. These determinations were documented in three Closeout Documents that were completed in 1998, 1999, and 2000.

V. SUMMARY OF SITE CHARACTERISTICS AND EXTENT OF CONTAMINATION

A. SITE CHARACTERISTICS

1. Site Topography

TYAD lies in the southern New York section (locally termed the Pocono section) of the Appalachian Plateau Physiographic Province. Mature glaciated plateaus of moderate relief with broad intervening lowlands characterize the section. Within TYAD, the relief varies over a range of approximately 220 feet (ft); the lowest elevation (1,930 ft) occurs south of Barney's Lake and the highest elevation (2,150 ft) occurs on Powder Smoke Ridge, the location of OU-4.

2. Surface Water Hydrology

Figure 4 shows the surface drainage features at TYAD. No through-flowing drainage ways exist on TYAD. Surface drainage, originating within TYAD, flows principally into Cross Keys Run, Barney's Lake, and Hummler Run. Oakes Swamp receives drainage from the western and northern portions of TYAD and discharges to the north-northwest.

12 3. Geology

The shallow, geologic materials present at TYAD primarily consist of materials derived from continental glaciation (i.e., differentially scoured bedrock or deposited glacial material). Deposits include peat of Holocene age, which occurs in level, undrained or poorly drained swampy areas in natural lowland depressions.

A number of deposits of Pleistocene age are also present at TYAD. Boulder field material, consisting of poorly sorted angular to rounded boulders ranging in size from a few centimeters to a meter in diameter, has been identified on site. These deposits are tightly to loosely packed, with abundant open interstices except where covered by vegetation.

End moraine material of Pleistocene age is also present and is comprised of materials ranging from till to ice-contact stratified drift materials. The till is reddish-brown, sandy to very sandy, stony to very stony with a minor clay content, moderate to high porosity and permeability, and compact and coherent to relatively noncohesive. Boulders commonly present may be up to 2.4 meters in diameter. The ice-contact stratified drift is composed of subangular-to rounded-pebbles, cobbles, and sand of variable thicknesses and degree of sorting. It is characterized by marked hummock topography with small hills and undrained depressions. Local relief on these materials is variable, but generally 3 to 6 meters. The typical thickness of these deposits is variable, with a range of 3 to 29 meters, and an average thickness of 14 meters.

Pleistocene ground moraines, comprised of reddish-brown to dark-brown till (unsorted mixture of clay, silt, sand, and gravel), are also present. This till can be sandy, stony to very stony, with variable clay content, moderately cohesive, generally containing a complete range of particle sizes of angular to rounded pebbles, cobbles, and boulders up to a few feet in diameter. Ground moraines, comprised of till, generally conform to the preglacial topography of the underlying bedrock, with surfaces generally even and relatively smooth; scattered boulders on the land surface are rare to common. Stony ground moraine is comprised of till with surface and topography similar to that for ground moraine except for the number of surface boulders. Boulders up to 1.2 to 1.5 meters in diameter are common and often completely cover the till surface. The thickness of these materials is variable, with a range of 1.5 to 23 meters and an average of 11 meters.

13 The soils covering much of AOC #55 are generally classified as extremely stony loam and extremely stony silt loam, at slopes ranging from 1 to 25 percent. The site is also wooded, with dense underbrush and marshy low spots.

4. Ecology

AOC #55, located on Powder Smoke Ridge, is a forested ridge that rises from approximately 1,930 to 2,150 feet mean sea level. This northern portion of TYAD is forested and is the most natural and least disturbed area of TYAD. Varied habitats are located in this natural area including upland forest, boulder fields, forested wetlands, marshes, bogs, ponds and streams. Wildlife is very abundant in upland- forested habitats of TYAD. Mammals that were observed in the area of AOC #55 include: white-tailed deer, black bear, red squirrel, eastern chipmunk, and deer mouse. Species that are expected to inhabit this area are opossum, raccoon, bobcat, coyote, gray fox, striped skunk, flying squirrel, porcupine, and gray squirrel. Numerous species of birds and reptiles are also present in this habitat. (PMC, 2000)

B. EXTENT OF CONTAMINATION

The UXO Archive Search Report (USACE, 1995) included copies of incident reports showing that UXO at AOC #55 has been dealt with on an "as-found" basis. When a UXO or suspect UXO item is observed, Army Explosive Ordnance Disposal (EOD) personnel are brought in to identify and dispose of the item(s). Both live and inert items have been found in this area in the past. For example, in May 1995 a fuzed 155 mm high explosive (HE) projectile was discovered and detonated in place approximately 1,000 feet from TYAD's water tower (USACE 1995).

From October to December 1998, the Army conducted removal activities to clear approximately 20 acres of land within AOC #55 for construction of a radar testing facility. The footprint of the radar testing facility and an area 100 feet around the footprint of the facility were cleared to a depth of four feet. The fence line and fence line footprint were also cleared to a depth of four feet. All other areas within the construction site were cleared to a depth of one foot. The following list is the Ordnance and Explosives (OE)/UXO found in this area:

14 OE/UXO Type Amount 37 mm Projectile 187 75 mm Projectile 26 81 mm Mortar 2

M38 Fuze 1 M49 Flare 1 Adapter Booster 1 U.S.C.G. 3 Projectiles

UXO is an explosive ordnance which has been primed, fuzed, armed, or otherwise-prepared for action, and which has been fired, dropped, launched, projected, or placed in such a manner as to constitute a hazard to operations, installations, personnel, or materiel, and remains unexploded either by malfunction or design or for any other cause.

Not all munitions and related items encountered at AOC #55 have been or are expected to fit the definition above. Some munitions used for training are inert and contain no or only small charges or pyrotechnics. However, because detailed records of types and quantities of munitions fired over the years at TYAD have not been discovered, it is conservative to assume that all items encountered are UXO and should be treated as such unless proven otherwise by professional EOD personnel.

Attachment 2 contains technical information on the types of explosives and other ordnance that may have been fired at the Tobyhanna artillery range. Comparing (Figure 2) and the firing range map (Figure 5), shows that the 20 acre radar testing facility construction site is directly within the former impact area on the top of Powder Smoke Ridge. Therefore, it is reasonable to assume that UXO found at the 20 acre site would be representative of the types and density of UXO present in the entire former impact area, and that UXO present on the rest of AOC #55 (outside the former impact area) would generally be of the same types, but probably at a lower density.

VI. CURRENT AND FUTURE LAND USES

AOC #55 is hounded on the north and east by lands of the , and on the west by Gouldsboro Road, a two-lane state road connecting the towns of Tobyhanna and

15 Gouldsboro. State Game Lands lie to the west, beyond the state road. A portion of the southern boundary runs along Oakes Swamp, continuing through a wooded area to the eastern TYAD boundary. (See Figure 2). The perimeter of AOC #55 is currently patrolled on a regular basis "by TYAD security. Warning and no trespassing signs are posted along the entire perimeter of AOC #55.

Construction of a radar-testing facility is nearing completion at this time on 20 acres of AOC #55. As discussed in Section V.B., this area was cleared of UXO prior to construction. The radar testing facility, which will be used on a regular basis, will be fenced off from the remainder of AOC #55. In addition, two water towers used for the storage of drinking water are located in AOC #55. The water towers are also fenced off from the remainder of AOC #55. There are currently no other uses of the remaining acreage of AOC #55.

Future land use will in all likelihood remain the same as the current land use. TYAD presently has no plans to develop any more of AOC #55.

VII. SUMMARY OF SITE RISKS

The presence and handling of UXO present significant physical hazards. Access to the UXO site must be controlled to minimize the threat of explosion and injury to people. If UXO is discovered, it may also cause injury if it is not handled properly.

Exposure to explosive chemical hazards or chemical warfare material is not anticipated because chemical munitions were not used at the depot. However, if UXO is eroded to a condition where the explosive is exposed, there exists a slight possibility of chemical exposure through skin absorption. There is no hazard from inhalation since explosives are cast into the round.

As part of the UXO Archive Search Report, USACE performed a risk assessment following Army explosive safety policies (USACE, 1995). This risk assessment was performed for the former Tobyhanna Artillery Range as a whole, except for the area that is now listed AOC #55. AOC #55 was not evaluated in the 1995 USACE Archive Search Report because it is within the current boundary of an active Department of Defense (DoD) installation; the UXO Archive Search Report process focused on Formerly Used Defense Sites (FUDS) -- those ranges on property outside the

16 TYAD boundary. However, the findings of the 1995 UXO Archive Search Report were consistent with the UXO found during construction of the radar testing facility on Powder Smoke Ridge (HFA, 1999), particularly with respect to the types and density of the UXO encountered in the impact area. In addition, the U.S. Department of Health and Human Services, Agency for Toxic Substances and Disease Registry performed a Public Health Assessment for Tobyhanna Army Depot in 1997. That report concluded that on-post precautions, such as a fence and warning signs, would be protective, but where a fence and signs were not installed, UXO may pose a physical hazard to hunters and the public.

In light of the findings in the 1995 USACE Archive Search Report, the 1997 HHS Public Health Assessment, and the UXO discovered during construction of the radar testing facility, the Army has adopted a conservative approach that favors protecting the public.

As described in "The Risk Assessment Procedures for Ordnance AD Explosive (OE) Sites", (Attachment 2), a risk assessment is composed of two factors: hazard severity and hazard probability. "Hazard severity" is a qualitative measure of the worst credible mishap resulting from exposure to various types and quantities of UXO items. The UXO items discovered at AOC #55 have been medium to large caliber conventional ordnance (20 mm and greater), yielding a scoring value of 10. As previously noted, a single 81 mm mortar containing white phosphorus was discovered, which also yields a scoring value of 10. No bulk explosives, bulk propellant, chemical or radiological weapons were found on any of the other ranges, and none were found during the construction support/clearance within AOC #55; thus, it is assumed that none of these are present, yielding scoring values of zero for each of these three categories. The total hazard severity value for AOC #55 is 20. This results in a Category II (Critical) hazard.

As explained in Attachment 2, "hazard probability" is the probability that a hazard has been or will be created due to the presence of UXO. UXO items have been discovered on the ground surface at AOC #55, yielding a scoring value of 5. The nearest occupied structure is the new radar testing facility on Powder Smoke Ridge,,less than 1,250 feet away; this yields a scoring value of 5. More than 26 buildings are within a 2-mile radius of AOC #55, yielding a scoring value of 5. Many buildings of varying uses are within the 2-mile radius, yielding an additional scoring value of 5. AOC #55 is within the boundary of

17 TYAD, and there are no current or future plans to transfer the land from Government ownership; this yields a site dynamics scoring value of zero. The total hazard probability value for AOC #55 is 20, which is a Level B (Probable) hazard.

As shown in Attachment 2, the hazard severity value and the hazard probability value are combined to determine a risk assessment value. The point on the risk assessment table where the severity and probability values intersect is called the Risk Assessment Code (RAC). Combining the values for AOC #55 yields a RAC of 2, which indicates a high priority site where further action is recommended.

While the hazard severity assessment is a function of the types of UXO found the risk assessment process shows that the risks can be reduced by changing the area, extent, and/or accessibility of contamination. The distance to the nearest occupied building is unlikely to change unless TYAD's mission is changed. Since a mission change is not anticipated, the scoring value for this category is not likely to change. Likewise, the number and types of buildings within a 2-mile radius is also unlikely to change. The barbed wire fence and warning signs would reduce accessibility to the site, but without annual maintenance and other institutional controls, access to the UXO will not be minimized. Thus, the two avenues available at AOC #55 to reduce the hazard probability to a Level C (Occasional) hazard are changing the location of the UXO hazard clearance and reducing accessibility to the site.

The response action selected in this Record of Decision is necessary to protect public health and welfare from actual or threatened releases of hazardous or dangerous substances and which may present an imminent and substantial endangerment to public health or welfare.

VIII. REMEDIAL ACTION OBJECTIVES

The Remedial Action objectives for AOC #55 are to:

! Reduce potential exposure to UXO by onsite workers or trespassers.

! Ensure that proper UXO clearance procedures are followed if or when any portion of this area is to be developed by the Army in the future.

18 ! Restrict future uses of the land.

! Educate the Public/Employees on the dangers of UXO at AOC #55.

IX. DESCRIPTION OF ALTERNATIVES

Alternative #1 - No Further Action (NFA)

This alternative means that no action will be performed under existing or future land-use scenarios. No UXO would be removed from the AOC #55, and no additional institutional controls would be established. This alternative is included as a baseline for comparison to other alternatives.

Capital Costs: $0 Operation and Maintenance ("O&M") costs: $0 Total Cost $0 Time to complete 0 years

Alternative #2 - Institutional Controls

This alternative involves actions that do not include removal of UXO from AOC #55, but lower the risk to TYAD personnel or visitors and the public by reducing the chance of UXO exposures or accidents. Important components of this alternative are access controls, UXO support from EOD-trained personnel during potential future intrusive activities, incorporation in the base master plan, and ongoing education. These actions limit access to areas in which surface UXO is likely to be encountered, prevent an accidental detonation during future intrusive activities, and warn TYAD personnel or visitors and the public of potential UXO hazards. Alternative #2 consists of the following actions:

Physical Controls - Maintenance of the barbed wire fence and signs posted around the perimeter of OU-4.

Security Patrols/Monitoring - Increased security patrols to minimize the number of trespassers onto OU-4, especially during periods of increased pedestrian activity (e.g., hunting season). In addition, the Environmental Management Division ("EMD") will monitor OU-#4 as part of the division's AOC monitoring plan.

19 UXO Support - Use of EOD-trained personnel to provide support in the case that any future intrusive activities by the Army take place within OU-#4. This requirement will be incorporated into the base Master Plan. All plans for future use of the area will be reviewed by EMD.

Proprietary Controls - Deed restrictions on the land if it is ever transferred outside the Government.

Public/Employee Education - Informing the public and TYAD employees of the dangers of contact with potential UXO.

Periodic Review - In accordance with CERCLA, a review at a minimum of every five years to determine the effectiveness of the remedy. In addition to the five-year review, a report will be provided annually to the EPA reviewing the effectiveness of the monitoring program.

Capital Costs: $0 O&M costs: $165,000 Total Cost $165,000 Time to complete 30 years *

* A 30-year time period is used by the Army to analyze "Cost to Complete". "Cost to Complete" is a term of art used to estimate costs. Actual completion time could exceed 30 years.

Alternative #3 - UXO Surface Clearance with Institutional Controls

This alternative includes a surface clearance to remove all UXO accessible without excavation. The major benefit of this alternative is that the most readily accessible UXO (which would account for most UXO exposures) would be removed. In addition, the costs for surface clearance are significantly lower than for a subsurface clearance since time is not spent excavating every, subsurface contact.

Surface clearance of AOC #55 would cover the entire site as shown in Figure 2, with the exception of the newly constructed test facility on Powder Smoke Ridge, as clearance has already been performed in that area as described earlier. The total area to be cleared is approximately 300 acres; the majority of this area is wooded with dense underbrush, and the ground surface ranges from uneven and rocky to low-lying and swampy.

20 EOD-trained personnel would perform surface clearance using magnetometers. All UXO recovered would be disposed of in place by detonation according to established Army procedures. Inert items and scrap would be sent for off-site disposal as appropriate. Quality control procedures would be in place to ensure that performance requirements are being met.

Even if a surface UXO clearance is conducted, it is anticipated that the institutional controls described in Alternative #2 would be required to meet the remedial objectives.

Because UXO could remain beneath the ground surface and be worked to the surface by frost heave and/or erosion, warning signs, gates, and education would still be needed. Security patrols could be decreased or dropped, but because the patrols exist currently and serve to keep unauthorized access to TYAD property to a minimum, it is likely that patrols would continue around the perimeter of AOC #55 regardless of whether UXO clearance is performed.

The need for construction support during intrusive activities would be unchanged, as no subsurface UXO would be removed in this alternative. Periodic review required by CERCLA would still be necessary because UXO would remain on-site. As part of the periodic review, a surface sweep of selected areas would be performed no less than every five years to assess the extent to which potential UXO has migrated to the surface.

Capital Costs: $ 493,700 O&M costs: $1,107,300 Total Cost $1,601,000 Time to complete 30 years*

Alternative #4 - UXO Clearance to 1 Foot with Institutional Controls

This alternative includes removal of potential UXO detected at or above one (l)- foot below ground surface, including surface UXO.

Clearance of UXO to 1-foot below ground surface of AOC #55 would cover the entire site as shown in Figure 2. Because AOC #55 is wooded with dense underbrush, Explosive Ordnance Disposal (EOD) trained personnel would employ magnetometers to

21 detect metallic objects on the surface and magnetic anomalies in the subsurface. All anomalies would be excavated until the source of the anomaly is found or until a depth of 1 foot is reached.

As with the surface clearance alternative, all UXO recovered would be disposed of in place by detonation according to established Army procedures. Inert items and scrap would be sent for off-site disposal as appropriate. Quality control procedures would be in place to ensure that performance requirements are being met.

Even if a UXO clearance is conducted to a depth of 1 foot bgs, it is anticipated that the institutional controls described in Alternative #2 would be required to meet the remedial action objectives because UXO would remain in the subsoil.

Because UXO could remain beneath the 1-foot mark but above the frost line, UXO could still be worked to the surface by frost heave and/or erosion. Hence, warning signs, gates, and public education would still be needed. Security patrols could be decreased or dropped; because patrols support the depot’s mission, it is likely that the patrols would continue around the perimeter of AOC #55 regardless of whether UXO clearance is performed.

Construction support during intrusive activities would be required because Army policy requires clearance to the depth of excavation plus a safety factor; a one-foot clearance would not provide any safety factor for intrusive activity. CERCLA periodic reviews would still be necessary because UXO would remain on site. As part of the periodic review, a surface sweep of selected areas would be performed, no less than every five years to assess the extent to which potential UXO has migrated to the surface.

Capital Costs: $ 882,750 O&M costs: $2,445,300 Total Cost $3,398,000 Time to complete 30 years*

Alternative #5 - UXO Clearance to Four (4) feet with Institutional Controls

This alternative includes removal of potential UXO detected at or above four feet below ground surface, including surface UXO. Clearance to four feet represents the approximate

22 reliability limit of current UXO detection technology.

Clearance of UXO to 4-feet below ground surface would include all of AOC #55 described in Figure 2. Because the area consists of woods and dense underbrush, EOD-trained personnel would employ magnetometers to detect metallic objects on the surface and magnetic anomalies in the subsurface. All anomalies would be excavated until the source of the anomaly is found or until a depth of 4 feet is reached.

This alternative would be especially difficult to accomplish with reliability because the majority of the site contains extremely rocky sub-soils. In addition, clearance to four feet typically is very disruptive to the natural environment if a significant number of digs and/or detonations is required. Given the rocky nature of the majority of site soils, no penetration calculations have been performed; hence, it is also unknown if buried ordnance would exist to a depth of four feet.

As with the other clearance alternatives (Alternatives 3 and 4), all recovered UXO would be disposed of in place by detonation according to established Army procedures. Inert items and scrap would be sent for off-site disposal as appropriate. Quality control procedures would be in place to ensure that performance requirements are being met.

If a UXO clearance is conducted to a depth of four feet, which is beneath the frost line, the potential for UXO movement due to frost is decreased. Only significant erosion would expose additional UXO remaining beneath the surface. For this reason, institutional controls such as warning signs, gates, and education would probably be unnecessary. In addition, security patrols could be decreased or dropped, but given the military mission of the depot, it is likely that patrols would continue around the perimeter of AOC #55 regardless of whether UXO clearance is performed.

The need for construction support during intrusive activities would be removed for shallow excavations (less than three feet), as long as Army policy regarding safety factors was met. Periodic CERCLA reviews would still be necessary because UXO below the four foot level could not be detected with available technology in this terrain and the potential for erosion or significant frost upheaval would still exist. As part of the periodic reviews, a surface sweep of selected areas

23 would be performed, no less than every five years to assess the extent to which potential UXO has migrated to the surface.

Capital Costs: $1,255,800 O&M costs: $1,433,500 Total Cost $2,690,000 Time to complete 30 years*

X. COMPARATIVE ANALYSIS OF ALTERNATIVES

The purpose of this section is to provide a comparison of the five alternatives against each other and the nine evaluation criteria outlined in the NCP at 40 CFR § 300.430(e)(9),(iii). The criteria are as follows:

Threshold Criteria

" Overall protection of human health and the environment. " Compliance with Applicable and Relevant and Appropriate Requirements (ARARs)

Primary Balancing Criteria

" Long-term effectiveness " Reduction in toxicity, mobility, or volume through treatment " Short-term effectiveness " Implementability " Cost

Modifying Criteria

" State acceptance " Community acceptance

Overall Protection of Human Health and the Environment

Overall protection of human health and the environment addresses whether each alternative provides adequate protection of human health and the environment and describes how risks posed through each exposure pathway are eliminated, reduced, or controlled, through treatment, engineering controls, and/or institutional controls.

24 Of all five alternatives, only the NFA alternative is not believed to be sufficiently protective of human health and the environment. Although there is a fence in place and warning signs, there would be no institutional controls to ensure that the fence is maintained. Also there would be no provisions for UXO support in the event that future use of the area is anticipated.

Compliance with Applicable or Relevant and Appropriate Requirements

Section 121(d) of CERCLA and NCP h300.430(f)(1)(ii)(B) require that remedial actions at CERCLA sites at least attain legally applicable or relevant and appropriate Federal and State requirements, standards, criteria, and limitations which are collectively referred to as “ARARs”, unless such ARARs are waived under CERCLA section 121(d)(4).

Applicable requirements are those cleanup standards, standards of control, and other substantive requirements, criteria, or limitations promulgated under Federal environmental or State environmental or facility siting laws that specifically address a hazardous substance, pollutant, contaminant, remedial action, location, or other circumstance found at a CERCLA site. Only those State standards that are identified by a state in a timely manner and that are more stringent than Federal requirements may be applicable.

Relevant and appropriate requirements are those cleanup standards, standards of control, and other substantive requirements, criteria, or limitations promulgated under Federal environmental or State environmental or facility siting laws that, while not "applicable" to a hazardous substance, pollutant, contaminant, remedial action, location, or other circumstance at a CERCLA site address problems or situations sufficiently similar to those encountered at the CERCLA site that their use is well-suited to the particular site. Only those State standards that are identified in a timely manner and are more stringent than Federal requirements may be relevant and appropriate.

Compliance with ARARs addresses whether a remedy will meet all of the applicable or relevant and appropriate requirements of other Federal and State environmental statutes or provides a basis for invoking a waiver.

25 With respect to AOC #55 UXO contamination, there are no ARARs addressing TJXO contamination at inactive ranges. DoD and the Army, however, have issued policy and/or guidance addressing explosive safety concerns which are “to be considered” (“TBC”) for the UXO clearance and control of Alternatives 3, 4 and 5.

The Army uses several policy documents or directives that address explosive safety. These TBCs are:

C Department of Defense Directive 6055.9-STD, Department of Defense Ammunition and Explosives Safety Standards, July 1999.

C Department of Defense Directive 4715.12, Environment and Explosives Safety Management on DoD Active and Inactive Ranges within the United States, August 17, 1999.

C Headquarters Army Letter 385-98-1, Explosives Safety Policy for Real Property Containing Conventional Ordnance and Explosives, June 30, 1998.

C Army Regulation 385-64, Ammunition and Explosives Safety Standards

C Army Pamphlet 385-64, Ammunition and Explosives Safety Standards

With the exception of the NFA alternative, all alternatives would meet the Army TBC safety requirements for clearance and control of property containing UXO.

Long Term Effectiveness and Permanence

Long-term effectiveness and permanence refers to expected residual risk and the ability of a remedy to maintain reliable protection of human health and the environment over time, once clean-up levels have been met. This criterion includes the consideration of residual risk that will remain onsite following remediation and the adequacy and reliability of controls.

With the exception of the NFA alternative, all alternatives would significantly reduce the risk of exposure to UXO at AOC #55. Because TYAD is expected to remain an active military facility, the existing perimeter security patrols will continue, and land use decisions at AOC #55 will be controlled by the Army, implementation of Alternative #2, institutional controls, will significantly reduce the risk to the public, because it

26 will prevent trespassing on Army property. Maintenance of the fencing that was installed as a removal action would be critical to the long-term effectiveness of this remedy.

The three alternatives involving UXO clearance (Alternatives #3, #4 and #5) would all be limited by the rocky terrain and dense ground cover at AOC #55. Alternative #3 would be effective in removing the most hazardous (surface) UXO, but to ensure long-term protection UXO clearance would need to be performed at regular intervals until a sufficient number of intervals have passed without the discovery of additional UXO on the surface. This also applies to Alternative #4, clearance to one foot below ground surface. If UXO remains above the frost line, surveying for UXO migration resulting from frost heave or erosion will be necessary to ensure clearance for the future.

Alternative #5, clearance to four-feet, would be effective in the long term, if clearance to that level can be achieved given the site constraints (terrain and ground cover) and the limits of UXO detection technology.

CERCLA reviews at least every five years would be necessary to evaluate the effectiveness of any of the five alternatives because UXO would remain on-site and would continue to present a risk to trespassers.

Reduction of Toxicity, Mobility, or Volume through Treatment

Reduction of toxicity, mobility, or volume through treatment refers to the anticipated performance of the treatment technologies that may be included as part of a remedy.

Alternatives #1 and #2 would not reduce the volume of UXO at AOC #55. Alternatives #3 through #5 would reduce the volume through clearance, and the magnitude of the reduction would increase as the clearance depth increases from surface to four-feet below ground surface.

Short-Term Effectiveness

Short-term effectiveness addresses the period of time needed to implement the remedy and any adverse impacts that may be posed to workers, the community and the environment during construction and operation of the remedy.

All of the alternatives including Alternative #1, the No Further Action Alternative, are effective in the short term

27 because the fence, signs and gates that have been erected as a result of the removal action, effectively control access to AOC #55. However, Alternative #2, institutional controls would be inherently safer for workers than the UXO clearance alternatives (Alternatives #3, #4, and #5), which would require handling pf the UXO. Strict control of site access would be maintained, as necessary, by the EOD-trained personnel during clearance and detonation activities to minimize risks to other personnel and the public. Alternatives #3, #4, and #5 are also effective in the short term because UXO would be removed. However, UXO clearance in Alternatives #3, #4, and #5 would be very disruptive to the environment at AOC #55. Underbrush may be cut, numerous digs to identify anomalies would be conducted for the subsurface clearance activities, and items detonated in place would disrupt wildlife and create craters in the ground surface. Surface clearance (Alternative #3) would be less intensive and would pose fewer adverse impacts to workers than clearance to one foot (Alternative #4). Similarly, these alternatives would be less intensive and pose fewer potential adverse impacts to workers than clearance to four feet (Alternative #5).

Implementability

Implementability addresses the technical and administrative feasibility of a remedy from design through construction and operation. Factors such as availability of services and materials, administrative feasibility, and coordination with other governmental entities are also considered.

Alternatives #1 and #2, institutional controls, do not pose significant technical issues; however, the UXO control components of Alternatives #3, #4 and #5 are expected to pose significant technical difficulties and have the greatest number of unknowns. Because the area has not been used as an artillery range in more than 50 years, it is wooded with dense underbrush, much of which would need to be removed to facilitate the surface UXO clearance. Powder Smoke Ridge is also very rocky and covered with large boulders in many areas, which makes clearance to any depth difficult, especially to a relatively deep four feet below ground surface.

There are no administrative difficulties anticipated with any of the alternatives.

Cost

28 The estimated present worth costs for the alternatives, not including the No Further Action Alternative, range from $100,000 for Alternative #2 to $3.3 million for Alternative #4. The cost of each alternative increases as the clearance depth below ground surface increases.

State/Support Agency Acceptance

The Commonwealth supports Alternative #2. The Commonwealth does not believe that Alternative,#1 provides adequate protection of human health and the environment. The Commonwealth does not support Alternatives #3, #4 and #5 because of cost and implementability factors.

Community Acceptance

The community supports Alternative #2. At the Restoration Advisory Board (RAB) meeting held on July 20, 2000 the RAB members in attendance concurred with Alternative #2. The RAB members support Alternative #2 because it is protective of human health and the environment while being the most cost effective.

XI. PRINCIPAL THREAT WASTES

The NCP establishes an expectation that EPA will use treatment to address the principal threats posed by a site wherever practicable (NCP §300.430(a)(1)(iii)(A)). Identifying principal threat wastes combines concepts of both hazard and risk. In general, principal threat wastes are those source materials considered to be highly toxic or highly mobile which generally cannot be contained in a reliable manner or would present a significant risk to human health or the environment should exposure occur.

Because UXO would present a significant risk to human health should exposure occur, it is considered to be a principal threat waste. All of the alternatives, except Alternative #1. would address the principal threat waste. Alternative #2, Institutional Controls, would be effective in addressing the principal threat waste by containing it and restricting access to it rather than treating it. While treatment of the principal threat waste is preferred, the complexity of the site (e.g. dense underbrush and rocky terrain) makes implementation of treatment technologies virtually impracticable, particularly in light of the limitation of current UXO detection equipment. In addition, implementation of a treatment-based remedy (i.e.,

29 clearance and detonation in place as described in Alternatives #3, #4 and #5) would result in greater overall risk to human health and the environment due to risks posed to workers during implementation.

XII. SELECTED REMEDY

Summary of the Rationale for the Selected Remedy

The Army and the EPA, in consultation with PADEP, have selected Alternative #2, Institutional Controls, as the selected remedy for AOC #55. This alternative includes maintenance of the physical controls (i.e., fencing and signs), increased security patrols, proprietary controls, if necessary, public education, and periodic review. Alternative #2 meets the remedial action objectives of personnel and public education, protection from surface UXO, and protection from subsurface UXO during possible future intrusive activities.

The selected remedy is believed to provide the best balance of trade-offs among the alternatives with respect to the NCP response criteria. The Army, the EPA and PADEP believe that the selected remedy would be cost effective. This remedy is also favored over other alternatives with respect to its implementability. Although this action does not reduce the volume of UXO by treatment, the implementability of any alternative that would satisfy this criterion would be much more costly and would be difficult to implement due to the terrain and the overgrowth of the, area.

Although there are no Applicable or Relevant and Appropriate Requirements (ARARs), the Army will refer to To Be Considered (TBC) documents related to explosives safety.

The selected remedy is also endorsed by the Commonwealth and the community.

Detailed Description of the Selected Remedy

The selected remedy for OU #4 has the following components:

Physical Controls - In September 2000, TYAD completed construction of a barbed-wire fence around AOC #55 to prevent or deter access to the UXO area. In addition, warning signs were installed at regular intervals around the perimeter and at access points such as roads. Gates were installed across depot

30 roads to prevent unauthorized, inadvertent access by TYAD personnel or visitors; and the keys to the access gates will be controlled by depot Security personnel. Maintenance of the fencing and signs will be required.

Security Patrols/Monitoring - Also as part of the institutional controls, existing security patrols would be increased to minimize trespassing on TYAD property and AOC #55. Vehicle patrols will traverse the perimeter patrol roads on a regular basis. Trespassers will be fined, and the TYAD Environmental Management Division will keep a record of the number of trespassers. In addition, patrols will be increased during times when the area is expected to have increased pedestrian use (i.e., hunting seasons).

UXO Support - UXO support will be obtained from Army EOD-trained personnel if future intrusive activities occur within AOC #55, and the activities either exceed the depth of previous clearance actions, are in an area that was not cleared to the frost line, or are in an area that was not cleared because of the presence of pavement, buildings, or other structures. UXO support would not be required when modifying, servicing, removing, or otherwise accessing existing underground utilities or other structures that were installed after artillery training ceased at TYAD, as long as intrusive activities do not expand beyond the limits of the original excavation. This requirement will be incorporated into the base Master Plan. EMD will review all plans for use of the area.

Public/Employee Education - TYAD personnel and visitors with business in the vicinity of AOC #55 will be informed of the potential for UXO in the area. Information to be conveyed would include: a disclosure that the site was used for military training including the use of live ordnance, and that UXO may remain; the potential hazards associated with UXO; where UXO is likely to be found; what types of activities may be especially hazardous in the area; how to recognize potential UXO; what to do and what not to do when potential UXO is encountered; and whom to notify when potential UXO is discovered. Education may include display boards at roads leading into the AOC #5S area and/or posting on display boards in TYAD office spaces, public areas, and at the main gate where visitors sign in. Display boards are not required at points where the general public may approach AOC #55, such as along the boundary with Tobyhanna State Park. The intent of warning signs and patrols would be to keep the public out, and display boards are typically used to convey information only when access is encouraged or required.

31 Proprietary Controls - Deed restrictions will be placed on the land if it is ever transferred outside the Government.

Periodic Reviews - The purpose of periodic reviews is to ensure that this remedial action remains effective in protecting the public. Periodic reviews would be performed, at a minimum, at five-year intervals in accordance with CERCLA until it can be determined that reviews are no longer necessary. Each review would evaluate all aspects of the,selected remedy including UXO support and,response actions required, and the effectiveness of physical controls and education.

Elements of the periodic review are expected to include but are not limited to: • Review existing documents to determine what actions were proposed, what actions were completed, where UXO was suspected to exist and the rationale for that determination. • Obtain and review new data, such as: additional interviews not included in previous information; changes in site conditions such as construction, erosion, storm damage (uprooted trees), and changes in land use; documented UXO findings/incidents, if any; and evaluation of the video surveillance and other institutional controls. • Prepare a preliminary site analysis and work plans, if necessary, evaluate remedy effectiveness based on previous and new data, and identify additional data gathering requirements. • Perform fieldwork, if necessary, such as site visits, interviews, and verification sampling. • Prepare a final periodic review report, either substantiating that the remedy implemented is still protective of human health, or recommending that additional removal actions are needed.

Capital Costs: $0 O&M costs: $165,000 Total Cost $165,000 Time to complete 30 years *

Expected Outcomes of Selected Remedy

Upon implementation of the remedy for AOC #55, there is no anticipated change in use of the 400 acres of AOC #55. The

32 installation expects to own the land as long at Tobyhanna Army Depot is in operation. If portions of the land were to be used, or sold to a third party, the proprietary controls component of the institutional controls selected as part of this remedial action would come into effect to prevent any exposure to UXO.

XII. STATUTORY DETERMINATIONS

Pursuant to CERCLA §121 and the NCP, the selected remedy must be protective of human health and the environment, comply with applicable or relevant and appropriate requirements or justify a waiver, be cost-effective, and utilizes permanent solutions and alternative treatment technologies or resource recovery technologies to the maximum extent practicable. In addition, CERCLA includes a preference for remedies that employ treatment that permanently and significantly reduces the volume, toxicity, or mobility of hazardous wastes as a principal element and a bias against off-site disposal of untreated wastes. The following sections discuss how the Selected Remedy meets these statutory requirements.

Protection of Human Health and the Environment

The selected remedy, Alternative #2, will protect human health and the environment by preventing exposure to the UXO. Although no UXO would be removed under this alternative, it is believed that the maintenance of the fence and warning signs would reduce the risk of contact with potential UXO at AOC #55. The continuance of UXO support requirements during future construction activities at AOC #55 would protect construction personnel, and education efforts should help further reduce the risks from potential UXO. Also as part of the institutional controls, existing security patrols would be increased to minimize trespassing on TYAD property and AOC #55. Periodic reviews would assess the effectiveness of this alternative.

Compliance with Applicable or Relevant and Appropriate Requirements (ARARs)

There are no ARARs for the selected remedy. The selected remedy, Alternative #2, will comply with DoD and Army safety policies for the clearance and control of property containing UXO or potential UXO.

Cost-Effectiveness

33 The Selected Remedy is cost-effective and represents a reasonable value for the money. In making this determination, the following definition was used: "A remedy shall be cost- effective if its costs are proportional to its overall effectiveness." (NCP §300.430 (f) (1) (ii) (D)).

In making a determination of cost-effectiveness, the Army evaluated the “overall effectiveness” of any alternative that satisfied the NCP threshold criteria (i.e., were both protective of human health and the environment and ARAR- compliant). Overall effectiveness was then evaluated by assessing three of the five NCP primary balancing criteria (i.e., long-term effectiveness and permanence; reduction in toxicity, mobility, and volume through treatment; and short-term effectiveness). Overall effectiveness was then compared to costs to determine cost-effectiveness. The relationship of the overall effectiveness of this remedial alternative was determined to be proportional to its costs and, hence, this alternative represents a reasonable value for the money.

The estimated present worth cost of the Selected Remedy is $165,000.00. This is significantly less than the clearance alternatives and is much easier, faster, safer and less disruptive to the environment to implement.

Utilization of Permanent Solutions and Alternative Treatment Technologies (or Resource Recovery Technologies) to the Maximum Extent Practicable

A permanent solution for AOC #55 would require detection and detonation of all UXO. Existing detection technology is inadequate given the terrain at AOC #55.

The Army and EPA, in coordination with PADEP, have determined that the selected remedy represents the maximum extent to which permanent solutions can be utilized in a practicable manner at AOC #55. Alternative treatment technologies and/or resource recovery technologies were found to not be appropriate for site conditions. Of those alternatives that are protective of human health and the environment and comply with ARARs, the Army and EPA have determined that the selected remedy provides the best balance of trade-offs in terms of the five balancing criteria.

Preference for Treatment as a Principal Element

34 Treatment of UXO consists of detection and detonation. Because available detection technology is inadequate for this AOC, treatment is not a viable remedy.

Five-Year Review Requirements

Because this remedy will result in hazardous or dangerous substances, pollutants, or contaminants remaining at AOC #55 above levels that allow for unlimited use and unrestricted exposure, a statutory review will be conducted within five years after initiation of remedial action to ensure that the remedy is, or will be, protective of human health and the environment.

XII. DOCUMENTATION OF SIGNIFICANT CHANGES

The Proposed Plan for OU 4 was released for public comment on June 24, 2000. The Proposed Plan identified Alternative #2, institutional controls, as the Preferred Alternative. The Army, the EPA and PADEP reviewed all written and verbal comments submitted during the public comment period. It was determined that no significant changes to the selected remedy, as originally identified in the Proposed Plan, were necessary or appropriate.

XIII. RESPONSIVENESS SUMMARY

The purpose of the Responsiveness Summary is to provide the public with a summary of citizen comments, concerns, and questions about OU #4.

No written comments were received from the general public during the 30 day public comment period. In addition, no verbal comments were presented from the general public at the July 20, 2000 public meeting regarding OU #4.

REFERENCES

Phase II RCRA Facility Assessment Report for Tobyhanna Army Depot, A.T. Kearney, Inc., and Baker/TSA, May 1987

Evaluation of Solid Waste Management Units, TYAD, Groundwater Quality Survey No. 38=26-K914-90, United States Army Environmental Hygiene Agency, 26-30 March 1990

35 Letter from EPA Region III to TYAD, February 8, 1991 regarding Determination of No Action Areas of Concern

Letter from EPA Region III to TYAD, April 26, 1991 regarding Determination of Remaining Action Areas of Concern

Letter from EPA Region III to TYAD, June 28, 1991 regarding Verification Studies

Archives Search Report, Conclusions and Recommendations for the former Tobyhanna Artillery Range, Tobyhanna, Monroe and Wayne Counties, Pennsylvania, Project Number C03OA39602, U.S. Army Corps of Engineers, Rock Island District, September 1995

HQDA, 1998, Letter, Subject: Explosives Safety Policy for Real Property Containing Conventional Ordnance and Explosives. Headquarters, Department of the Army (HQDA), June 1998

Final Report, Construction Support Tobyhanna Army Depot, Tobyhanna, Pennsylvania, Human Factors Application, Inc., February 21, 1999

Engineering Evaluation/Cost Analysis Area of Concern 55 UXO Area on Powder Smoke Ridge, Program Management Company, April 17, 2000

36 ATTACHMENTS

37 ATTACHMENT 1

GLOSSARY OF TERMS

Administrative Record File: A compilation of documents that contains all information used to make a decision on the selection of a response action under CERCLA. The file is established at or near a Superfund site and is available for public review.

Area of Concern (‘AOC’): Geographical areas within TYAD that were identified in the Federal Facility Agreement and include Solid Waste Management Units under the Resource Conservation and Recovery Act, as well as other locations potentially representing a threat to human health and the environment.

Comprehensive Environmental Response, Compensation, and Liability Act (‘CERCLA’): A federal law enacted in 1980 and subsequently modified by the Superfund Amendments and Reauthorization Act of 1986 (SARA) and various other amendments. This Act resulted in the creation of a Trust fund, commonly known as Superfund, to investigate and clean up abandoned or uncontrolled hazardous waste sites.

Federal Facility Agreement (‘FFA’): An enforceable legal agreement between EPA and a Federal Facility in which the Federal Facility agrees to perform all activities related to site cleanup. The purpose of the FFA is to ensure that environmental impacts associated with known and potential areas of contamination are thoroughly addressed in accordance with applicable state and federal laws.

Information Repository: A location where documents and data related to a Superfund site investigations and response actions are maintained to allow the public access to this material.

National Priorities List (‘NPL’): EPA’s list of the most serious uncontrolled or abandoned hazardous waste sites identified for possible long-term remedial response actions.

Operable Unit (‘OU’): A portion of a Superfund site that has been conceptually separated to facilitate planning, management, and implementation of investigations and/or response actions.

38 Record of Decision (‘ROD’): A legal document that describes in detail the remedy selected for an entire Superfund site or a particular Operable Unit. The ROD summarizes the results of the investigative studies and includes a formal response to all comments supplied by the public.

Removal action: A response action taken to quickly address unacceptable risk to human health or the environment.

Unexploded Ordnance (‘UXO’): Explosive ordnance which has been primed, fused, armed, or otherwise prepared for action, and which has been fired, dropped, launched, projected, or placed in such a manner as to constitute a hazard to operations, installations, personnel, or materiel, and remains unexploded either by malfunction or design or for any other cause.

39 ` B. Pyrotechnics. (For munition not described above) VALUE

Munition (Container) Containing 10 White Phosphorous or other Pyrophoric Material (i.e., Spontaneously Flammable)

Munition Containing a Flame or Incendiary Material (i.e, Napalm, 6 Triethlaluminum Metal Incendiaries

Flares, Signals, Simulators, Screening 4 Smoke (other than WP) _

Pyrotechnics (Select the largest single value) 6

What evidence do you have regarding pyrotechnics? N/A

C. Bulk High Explosive (Not an integral part of conversion ordnance; uncontainerized.)

VALUE

Primary or Initiating Explosive 10 (Lead Styphnate, Lead Azide, Nitroglycerin, Mercury Azide Mercury Fulminate, Tetracene, etc.)

Demolition Charges 10

Secondary Explosives 8 (PETN, Composition A, B, C, Tetryl, TNT, RDX, HMX, HBX, Black Powder, etc.).

Military Dynamite 6

Less Sensitive Explosives 3 (Ammonium Nitrate, Explosive D, etc.).

High Explosive (Select the largest single value) 0

What evidence do you have regarding bulk explosives? N/A

D. Bulk Propellants (Not an integral part of rockets, guided missiles, or other conventional ordnance; uncontainerized)

VALUE

Solid or Liquid Propellants 6

Propellants 0

Propellants (Select the largest single value) 0

What evidence do you have regarding propellants? N/A

A 41 RAC Worksheet - Page 2 B. Chemical Warfare Material and Radiological Weapons VALUE

Toxic Chemical Agents 25 (Choking, Nerve, Blood, Blister)

War Gas Identification Sets 20

Radiological 15

Riot Control and Miscellaneous 5 (Vomiting, Tear)

Chemical and Radiological (Select the largest single value) 0

What evidence do you have of chemical/radiological OEW? N/A

TOTAL HAZARD SEVERITY VALUE

(Sum of the Largest Value for a through E--Maximum of 61) 10

Apply this value to Table 1 to describe Hazard Severity Category.

TABLE 1

HAZARD severity Description Category Hazard Severity Value

CATASTROPHIC I 21 and greater

CRITICAL II 10 to 20

MARGINAL III 5 to 9

NEGLIGIBLE IV 1 to 4

**NONE 0 0

* Apply Hazard Severity Category to Table 3.

** If Hazard Severity Value is 0, you do not need to complete Part II , Proceed to Part III and value a RAC score of 5 to determine your appropriate action.

RAC Worksheet - Page 3 A

42 Part II. Hazard Probability. The probability that a hazard has been or will be created due to the presence and other related factors of unexploded ordnance or explosive materials on a formerly used DOD site.

AREA, EXTENT, ACCESSIBILITY OF CONTAMINATION (Circle all values that apply)

A. Locations of OEW Hazards VALUE

On the surface 5

Within , Pipes, Vessels 4 or Ocher confined locations

Inside walls, ceilings, or other 3 parts of Buildings or Structures

Subsurface 2

Location (select the single largest value) 5

What evidence do you have regarding location of OEW? SI Team and Pictures

B. Distance to nearest inhabited locations or structures likely to be at risk from OE hazard (roads, parks., playgrounds, and buildings) VALUE Less than 125O feet 5

1250 feet to 0.5 miles 4

0.5 miles to 1.0 miles 3

1.0 miles to 2.0 miles 2

over 2 miles 1

Distance (Select the single largest value) 5

What are the nearest inhabited structures? The nearest building is 1 or 2 miles. However, are hiking trails through the State Park (Area "A") and live rounds have been found less than 1250 feet off the trail.

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43 C. Number of buildings within a 2 mile radius measured from the OE hazard area, not the installation boundary. VALUE 26 and over 5

16 to 25 4

11 to 15 3

6 to 10 2

1 to 5 1

0 0

Number of Buildings (Select the single largest value) 5

Narrative: There are approximately 20 buildings within the 2 mile radius which includes 4 State Park buildings. Additionlly many campers with tents and trailers, are there for the Spring, summer and Fall outings.

D. Types of Buildings (within a 2 mile radius)

VALUE Educational, Child Care, Residential, Hospitals, 5 Hotels, Commercial, Shopping Centers,

Industrial, Warehouse, etc. 4

Agricultural, Forestry, etc. 3

Detention, Correctional 2

No Buildings 0

Types of Buildings (Select the largest single value) 5

Describe types of buildings in the area. State park Maintenance buildings, Offices, Residential, Restaurant, Camping Trailers, Camping Tents and Storage Facilities for equipment and supplies/materials.

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44 E. Accessibility to site refers to access by humans to ordnance and explosive wastes. Use the following guidance: BARRIER No barrier or security system Barrier is incomplete (e.g., in disrepair or does not completely surround the site). Barrier is intended to deny egress from the site, as for a barbed wire fence for grazing. A barrier, (of any kind of fence in good repair) but no separate means to control entry. Barrier is intended to deny access to the site. Security guard, but no barrier Isolated Site a 24-hour surveillance system (e.g., television monitoring or surveillance by guards or facility personnel) which continuously monitors controls entry on the facility, or An artificial or natural barrier (e.g., a fence combined with a cliff), which completely surrounds the facility; and a means to control entry, at all times, through the gates or other entrances to the facility (e.g., an attendant, television monitor, locked entrance, or controlled access to the facility). Accessibility (Select the circle largest value) 5 Describe the site accessibility: There are no fences, but they do have a Few road gates (but not on all roads), although it wouldn’t matter, because anyone can have access to the area on foot. A main highway runs along the state Park (route 423) and there are main roads leading into the park itself. F. Site Dynamics - This deals with site conditions that are subject to change in the future, but may be stable at the present. Example would be excessive soil erosion by beaches or streams, increasing land development that could reduce distance from, the site to inhabited areas or otherwise, increase accessibility. VALUE Expected 5 None Anticipated 0 Site Dynamics (Select largest value) 0 Describe the site dynamics: This is Pennsylvania State Property and it is not anticipated they will sell off off any of the property, althrough they could expand the camping area. This would draw more visitors to the park. RAC Worksheet - Page 6

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Total Hazard Probability value (Sum of Largest Values for A through F--Maximum of 30) Apply this value to Hazard Probability Table 2 to determine Hazard Probability Level. TABLE 2 HAZARD probability Description Level Hazard Probability Value

FREQUENT A 27 or greater PROBABLE B 21 to 26 OCCASIONAL C 15 to 20 REMOTE D 8 to 14 IMPROBABLE E less than 8

* Apply Hazard probability Level to Table 3.

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46 Worksheet - Page 7 Part III. Risk Assessment, The risk assessment value for this site is determined using the following Table 3. Enter with the results of the hazard probability and hazard severity values.

TABLE 3

Probability FREQUENT PROBABLE OCCASIONAL REMOTE IMPROBABLE Level A B C D E Severity Category:

CATASTROPHIC I 1 1 2

CRITICAL II 1 2 3 4 5

MARGINAL III 2 3 4 4 5

NEGLIGIBLE IV 3 4 4 5 5

RISK ASSESSMENT CODE RAC

RAC 1 Expedite INPR, recommending further action by CEHND - Immediately call CEHND-ED-SY--commercial 205-955-4968 or DSH 645-4968.

RAC 2 High priority on completion of INPR - Recommend further action

RAC 3 Complete INPR - Recommend further action by CEHND.

RAC 4 Complete INPR - Recommend further action by CEHND.

RAC 5 Usually indicates that no further action (NOFA) is necessary. submit FOFA and PAC to CEHND.

47 FIGURES

48 49 50 51 52 53