Mid-Atlantic Superfund

EPA Region 3 (Mid-Atlantic)

Pennsylvania
Franklin County
5 miles north of Chambersburg

EPA ID# PA6213820503

3rd Congressional District

Last Update: June 2008

Other Names

Letterkenny Army Depot (LEAD)

Current Site Status

The Second Five Year Review Report of Letterkenny Army Depot is nearly complete. It is clear that numerous minor deficiencies exist that need to be corrected. Vapor intrusion remains a major concern and therefore the EPA will be deferring the protectiveness statement for the Five Year Review until enough sampling data is collected, as required by the SE OU 10 Record of Decision, to evaluate the risk caused by vapors from the VOC-contaminated groundwater into various buildings that overly the plume. Preliminary data indicates excessive sub-slab vapor concentrations of TCE and PCE in the vicinity of Buildings 37 and 47. Although the course remains uncertain, these issues may cause a delay in the Phase V BRAC property transfer or cause the need for an additional BRAC phase.

The BRAC boundary was revised in 2007 as a result of an agreement between the Letterkenny Industrial Development Authority and Letterkenny Army Depot, as sanctioned by the deputy assistant Secretary of the Army, to allow the depot to retain 225 acres of land adjoining the facility. As a result of the revised BRAC boundary, some of the sites that were administered under SE OU 8 are now administered under a new operable unit, SE OU 14, because they are to remain located in Army-retained land.
There are three remaining phases of BRAC property transfer planned for LEAD, Phase V, VI and VII. Each BRAC property transfer phase will be completed after a group of areas is deemed suitable for transfer after the CERCLA process is completed for the sites, which includes an RI/RA, FS, or Decision Document (as appropriate), PP, and ROD. In addition, a FOST will be prepared in accordance with the U.S. Army requirements.

Site Description

The Letterkenny Army Depot was originally a 19,243 acre Army facility, located 5 miles north of Chambersburg, Franklin County, Pennsylvania. Approximately 17,000 people live within 5 miles of the Letterkenny Army Depot. There are two NPL sites associated with the Letterkenny Army Depot. The first is referred to as the Letterkenny Army Depot Property Disposal Office (PDO) NPL site. The second is referred to as the Letterkenny Army Depot Southeast (SE) Area NPL site. This narrative will concentrate on the Letterkenny Army Depot SE area NPL site.

The Letterkenny Army Depot was established in 1942 for ammunition storage. Since 1947, however, activities at the Letterkenny Army Depot expanded to include (a) the testing, maintenance and overhaul of wheeled and tracked vehicles and missiles; (b) the storage and transportation of industrial chemicals and petroleum; and (c) storage, maintenance, demilitarization, and modification of ammunition. The Letterkenny Army Depot SE Area NPL site includes areas associated with the overhauling, rebuilding, and testing of wheeled and tracked vehicles, as well as warehousing operations.

The Letterkenny Army Depot was included in the 1995 Base Closure and Realignment Act (BRAC), with 1,462 acres designated for transfer to the private sector for local redevelopment, while the resulting 17,781 acres remain as part of the active Letterkenny Army Depot. To date, 792 acres have beeen transferred to the private sector, with 670 acres remaining to be transferred in the immediate future.

In 1983, volatile organic compound (VOC) contamination of the groundwater beneath the Letterkenny Army Depot (LEAD) SE Area was detected. In 1984, it was determined that the LEAD SE Area contained at least six major areas of VOC contamination and/or elevated levels of metals. Three of these areas were confirmed to have contributed VOC contamination to the groundwater. In particular, industrial waste lagoons located at the LEAD SE Area contributed to VOC groundwater contamination. The VOC contaminated groundwater plume migrated off-site and emanated from springs up to 2 miles to the east and south of the industrial waste lagoons. This same contaminated groundwater plume extended to off-post wells. After residential well sampling disclosed that presence of VOC-contaminated groundwater, the Army initially supplied affected residences with bottled potable water. By 1987, 38 residences and businesses were connected to the Guilford Water Authority water supply. In 1992, three additional residences were added to the water supply line.

Contamination from both NPL sites includes chlorinated organic solvents, blast media, paints, petroleum products, metals, and cleaning agents stored or disposed of in landfills, trenches, burn pits, or spilled from storage.

Site Responsibility

This site is being addressed by Federal action and Base Closure (BRAC 1995).

NPL Listing History

The Letterkenny Army Depot SE Area was proposed to the National Priorities List of the most serious uncontrolled or abandoned hazardous waste sites requiring long term remedial action on October 15, 1984. The site was formally added to the list on July 22, 1987.

Threats and Contaminants

Groundwater beneath the Southeast Industrial Area of the depot (Site 1), as well as beneath an off-depot area of approximately 4,000 acres, extending at least 2 1/2 miles to the east, is contaminated with chlorinated organic chemicals. Soil has been found to be contaminated with chlorinated organic chemicals, including volatile organic compounds (VOCs). Individuals may be at risk if they accidentally ingest, inhale vapors, or come in direct contact with contaminated groundwater or soil, or consume fish from contaminated areas. Additional residential wells could become contaminated.

Contaminant descriptions and associated risk factors are available on the Agency for Toxic Substance and Disease Registry, an arm of the CDC, web site at http://www.atsdr.cdc.gov/hazdat.html

Cleanup Progress

Environmental Studies began in 1978 and continue. The majority of the two NPL sites were identified in 1995 as excess and to be returned to the community for local reuse. The Army, EPA, and Pennsylvania signed an Interagency Agreement in 1989. The Army, state and EPA formed a BRAC Cleanup Team (BCT) in 1996 which is working closely to streamline the cleanup process, to expedite the cleanup, transfer and reuse of excess property to facilitate local redevelopment. Franklin County has formed a Local Reuse Authority (LRA) referred to as the Letterkenny Industrial Development Authority (LIDA) to support reuse and cleanup priorities.

The Letterkenny Army Depot SE Area NPL site has 12 Operable Units:

SE OU 1 K Area Contaminated Soils

The K-Areas were used for the disposal of waste generated from LEAD activities. The K-1 area (or K-1 Lagoon) was used to dispose of waste solvents used in painting, paint stripping, and degreasing operations at LEAD. The K-1 Area was in use from 1957 to 1970. Its dimensions were approximately 200 x 50ft. The Area of VOC-impacted soil was approximately 78 x189 ft.

The K-2 area was in use from 1965 to 1970 and included five (5) partially revetted areas used to accumulate solid waste prior to disposal into a nearby landfill. Its dimensions were approximately 270 x 75ft. It appears that when the K-1 lagoon was closed some soil from K1 ended up at K-2. The area impacted at K-2 was a 60 x 20 x ~10ft deep.

The K-3 area was in use as a drum storage area from 1965 to 1970 and covered an overall area of approximately 100ft. by 40 ft. Based on available soil analytical data, the actual contaminated area was limited to a 50 x 50ft. area. The K-areas were located in the Disposal Area of the Depot.

In 1983, a RI identified that the K-Areas contained high levels of VOCs. In 1989, a DA-wide soil gas investigation identified that high levels of VOCs existed in the vadose zone soils of the K-Areas. In 1992 the boundaries of the K-Areas were delineated. K-1 contained up to 5.5 % TCE and lead up to 1.5%. PCBs and SVOCs were also discovered.

A ROD was signed in August 1991. Remedial Action started in July 1993 and was completed in October 1995. The VOC-contaminated soils were excavated, treated with Low Temperature Thermal Desorption, returned to the site, and capped as a Class II Residual Waste Landfill. The Remedial Action addressed all environmental concerns of this OU. VOC-contaminated groundwater at this site will be addressed by OU 3- Southeast Onpost Contaminated Groundwater.

An ESD was finalized May 7, 2004 to implement Institutional Controls, Long-Term Maintenance, and Cap Inspection. The first 5 Year Review was completed in November, 2001.

SE OU 2 – Industrial Wastewater Sewer System and Contaminated Soils

Problems with the Industrial Wastewater Sewers (IWWS) were first identified in the 1993 Remedial Investigation (RI) Report for the Southeastern Area. Studies of the IWWS lines showed that numerous breaks and/or leaks existed in both the IWWS and Stormwater Sewer lines. Leak testing and sampling indicated that VOCs had leaked from the IWWS and migrated to the soil/bedrock interface. Emergency repairs were made to the IWWS beginning in October 1994 and were completed in December 1995. An engineering evaluation/cost analysis (EE/CA) was prepared by LEAD to address the removal of contaminated soils associated with the leaking IWWS lines. LEAD conducted an emergency removal action of the IWWS-contaminated soils east of Building 370 in summer 1997.

Remedial Investigation (RI) and Risk Assessment (RA) Reports were completed in September 1998 and June 2002, respectively. A Final FS was completed in November 2004 and a Proposed Plan was finalized in May 2005. A final Record of Decision (ROD) for SE OU 2 was signed in September 2006. The selected remedy for SE OU 2 was cleaning followed by abandonment of the sewer and drain lines at Building 37 and 57 to prevent future use of the existing sewers. The remedial action was completed in spring 2006. The risk assessment showed that there are acceptable risks for industrial and/or commercial use; therefore, the chosen remedy includes land use controls to prevent the use of the property for residential housing, elementary and secondary schools, child care facilities, and playgrounds.

SE OU 3 – Disposal Area VOC-Contaminated Groundwater

SE OU 3 was divided into two OUs (SE OU 3A and SE OU 3B) in 2002 so that the area upgradient of the VOC-contaminated groundwater from the Disposal Area source could be managed separately as SE OU 3B to facilitate the BRAC transfer.
SE OU 3A addresses on-post groundwater contamination in the Disposal Area (DA). Groundwater in the vicinity of the DA is contaminated with chlorinated solvents. Dye studies have shown that water from areas within SE OU 3A is discharging off-post (see SE OU 6). The source of this contamination was the DA. Although the primary sources of contamination have been addressed, VOCs are still being detected, most likely due to the presence of contaminated subsurface soils and VOC contamination within the bedrock matrix, which is continuing to act as a secondary source.
A Focused Feasibility Study (FFS) was initiated for the DA, which includes more recent RI data and risk assessment (RA) evaluations. A recirculation well Pilot Study has been completed. An In-situ H2O2 Pilot Study was completed in April 2000. Additional investigations to verify the vertical extent of groundwater contamination were conducted from 2005 to 2006. The results of the additional investigations will be reported in the FFS. A vapor intrusion pilot study was conducted from July 2004 to January 2006, and a draft report was submitted to EPA and PADEP in May 2006. The vapor intrusion sampling plan, which incorporated regulatory agency comments, was finalized in 2007. A remedy will be selected based on the completion of the feasibility study and documented in a ROD.

SE OU 3B is a BRAC OU that addresses the area upgradient of the VOC-contaminated groundwater from the DA source. Groundwater sampling was initiated in August 2003 and a final SI Report was finalized in May 2005. A Proposed Plan was issued for public review in May 2005. A no action ROD and a FOST were completed and signed in June 2006. The ROD specifies no action for SE OU 3B groundwater and for soil associated with four parcels that consist of a portion of SE OU 8; two of these parcels are to be transferred as part of the Phase IV BRAC property transfer.

SE OU 4 – Stormwater Sewer Lines and Associated Drainageways

SE OU 4, which is located in both the BRAC and ER,A portions of LEAD, consists of the stormwater sewer system and associated sediments. Prior to installation and connection to the IWTP, industrial wastewaters from the SE Area at LEAD were discharged, untreated, to the Depot stormwater sewer system. An EE/CA was prepared to cover the removal of contaminated sediment from the Southeast Drainage Way (between the headwall and Salem Road) and Rowe Run (between the headwall and State Route 997) and to address the emergency repair of associated sinkholes. An emergency removal of the sediments and filling of the sinkholes was completed by the spring of 1997. A total of 1,037 tons of contaminated sediment was removed and disposed of as residual waste.
A Removal Action Summary Report for SE OU 4, which indicated no unacceptable risk to human health or the environment, was finalized in September 2003. A Proposed Plan was issued for public review in November 2004, and a Record of Decision was completed in August 2005. The selected remedy was no further remedial action.

SE OU 5 – Areas A and B Contaminated Soils

SE OU 5 is comprised of two areas of contaminated soil, which are designated Areas A and B. They were initially investigated in the 1980s. Area A is primarily contaminated with total petroleum hydrocarbons (TPH) and metals, with a small amount of VOCs. The most recent rounds of sampling to delineate the extent of contamination were completed in July 1995, when a localized spill area of elevated VOC concentrations was identified. An EE/CA was prepared and an emergency removal action was conducted in summer 1997 to excavate and dispose of the VOC-contaminated soil in the spill area. The remainder of Area A was evaluated as part of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) RI process.
Area B was a former Oil Burn Pit (OBP). The soil in this area was found to contain TPH, metals, and a small amount of VOCs; groundwater was also found to contain VOCs. Area B was further evaluated as part of the CERCLA RI process.
VOC contamination at Areas A and B is attributed to the K Areas (SE OU 1) and the Area A spill area. A Final RI/RA was completed in October 2004; these were published separately as an RI and an RA. A worm bio-uptake study was conducted in accordance with comments from EPA Biological Technical Assistance Group (BTAG), and as a result, a draft addendum to the ecological RA was submitted in September 2006. The RA addendum is currently being revised to address EPA comments. An FS will be prepared following resolution of EPA comments on the ecological RA.

SE OU 6 – VOC-Contaminated Groundwater North of Gate 6 and East of East Patrol Road (Rowe Run Drainage System)

SE OU 6 includes the discharge points of 6 VOC-impacted off-post springs and off-post VOC-contaminated groundwater associated with SE OU 3A and SE OU 11, including residential drinking water wells. A final dye study, initiated in September 1995, included the placement of dye in on-post monitor wells located near LEAD’s property line and in Rowe Run (boundary trace). This study was completed in December 1995.

In addition to the springs, off-post wells were also evaluated as part of SE OU 6. Approximately 50 wells were sampled and results were analyzed for VOC and metals concentrations during the past 2 years. The results from this sampling indicated no additional VOC-contaminated off-post wells other than those previously identified.

A third study area of the off-post groundwater impacts was an evaluation of animals and animal products located on farms near the SE Area. Samples of eggs, milk, and meat were collected from numerous farms. VOCs and metals were detected at concentrations within the literature values or regional background levels for the media sampled.
A final RI/RA Report for SE OU 6 was submitted in November 2004. Additional investigations to verify the vertical extent of groundwater contamination were conducted from 2005 to 2006, the results of which will be included in the SE OU 6 FS. A vapor intrusion pilot study was conducted from July 2004 to January 2006, and a draft summary report is currently being revised to address regulatory comments. In order to address residual on- and off-post VOC-contaminated groundwater associated with SE OUs 6 and 11 at LEAD, a Work Plan for the Evaluation of the Vapor Intrusion Pathway at SE OUs 6 and 11 was finalized in June 2007. Vapor intrusion sampling is currently being conducted and will continue in the spring/early summer of 2008.
A draft Feasibility Study is expected for SE OU 6 in early 2008.

SE OU 7 – Truck Open Storage Area

Sampling of SE OU 7 was initially conducted in summer 1994. This area consisted of an open storage area for trucks and an abandoned septic tank and leach field system formerly used as an oil/water separator. Analytical results from this sampling have shown no significant soil contamination present at SE OU 7. The detected groundwater contamination is attributable to SIA sources, such as the formerly leaking IWWS gravity lines associated with Building 37. Groundwater at SE OU 7 was addressed under SE OU 10. During the investigation of SE OU 7, an abandoned septic system was found. The septic system was used as an oil/water separator for the disposal of sanitary sewage from LEAD holding tanks. A removal action was conducted in spring 1997, which consisted of characterization, solidification and removal of the tank contents, backfilling of the tank, and restoration of the site.
A supplemental investigation was conducted in 1999 for the presence of polychlorinated dibenzo-p-dioxins and dibenzofurans (dioxins/furans), and polychlorinated biphenyls (PCBs). The results of the investigation were published in July 2000 and showed that the presence of dioxins/furans in burned material was at concentrations greater than the published industrial screening levels for direct contact. A time-critical removal action was completed in this area in December 2000.

A draft Current Conditions Human Health Screening Level Risk Assessment and Screening Level Ecological Risk Assessment (SLRA/SLERA) was prepared for the TOSA/WOS site in August 2007. SE OU 7 is included in the Phase V BRAC property transfer, which will take place following the Army’s completion of the FS, PP, ROD, and FOST for the Phase V BRAC Parcels. This process, leading to FOST completion, is expected to begin in the fall of 2007.

SE OU 8 – BRAC Waste Sites

The SE OU 8 area is composed of potential waste sites identified in the to-be-excessed portion of the SE Area. SE OU 8 is being investigated under the BRAC investigation program.

Findings of Suitability to Lease (FOSLs) have been signed for the following SE areas: Buildings 6, 9, 19, 412, 416, 500, 522, 2291, 7, 8, and 42. Two FOSLs were also signed that covered the remainder of the BRAC buildings in the SE area. Property transfers under BRAC are being performed in phases. The following is a summary of the status of property transfers within the SE OU 8 area:

• Phase I — Properties within the SE portion included Parcels 1 through 13, Parcels 16 through 27, and Parcel 31. A ROD for the Phase I areas was signed in September 1998. A FOST was signed in October 1998. Phase I BRAC Property Transfer was completed in November 1998. The ROD for Phase I documented selection of land use controls to prevent contact with contaminated groundwater and to ensure that the land use remains commercial/industrial.
• Phase II — Properties within the SE portion included Parcels 2-35 through 2-77 (with the exception of Parcel 2-73), consisting of structures and property above the seasonal high groundwater table. A ROD for the Phase II areas was signed in July 2001. A FOST for the Phase II parcels was finalized in November 2001. Phase II BRAC Property Transfer was completed in May 2002. The ROD for Phase II documented selection of land use controls to prevent contact with contaminated groundwater and to ensure that the land use for certain areas remains commercial/industrial.
• Phase III — Phase III parcels are located within an area referred to as Southern Martinsburg Shale Region (SMSR). A no further action ROD for Phase III was signed in August 2003. A FOST for the Phase III parcels was signed in August 2003.
• Phase IV - A Proposed Plan was issued for public review in May 2005. The Phase IV Parcels ROD and FOST were signed in June 2006. Phase IV comprises approximately 60 acres (parcels 4-92 and 4-93). The ROD specified that no further remedial action is necessary for soil (SE OU 8) and groundwater (SE OU 3) to protect human health and the environment.
• Phase V – An FS is currently being prepared for the Phase V BRAC Parcels, which includes 19 SE OU 8 BRAC waste sites and SE OU 7, the TOSA/WOS site. The process leading to FOST completion is expected to begin in the fall of 2007.

SE OU 9 – Landfill J

SE OU 9 consists of a landfill that has been designated Landfill J, which is located west of Building 320. Landfill J was discovered in 1995 while trenching for utilities. The extent of the landfill was determined using geophysical techniques and trenching. The characteristics of the soils and groundwater were evaluated through several sampling efforts. An emergency removal action was conducted in June 2001. A finalized Removal Action Summary Report, which included the RI/RA data, was completed in October 2004. A draft FS was completed in May 2005 and is currently being revised to address regulatory review comments.

SE OU 10 – SSIA VOC-Contaminated Groundwater South of Gate 6 (Conococheague Drainage System)

SE OU 10 consists of contaminated groundwater south of Gate 6. SE OU 10 was created when SE OU 3 was divided at the groundwater/surface water divide near Gate 6. The sources of the groundwater contamination for SE OU 10 are the formerly leaking IWWS lines in the vicinity of Building 37 (VOC-contaminants) and a release from a diesel tank fuel line in the vicinity of Building 37.

A FFS Final Report was issued in September 2003. A final Proposed Plan was completed in February 2005, and a ROD was completed in March 2006. The selected remedy for SE OU 10 is Enhanced Biodegradation with Monitored Natural Attenuation and Land Use Controls (to prevent contact with contaminated groundwater until the time the groundwater is safe for use). A final Remedial Action Work Plan was completed in April 2007. The final sodium lactate injection for the selected remedy was completed at SE OU 10 in June 2007. A long-term groundwater monitoring program has been implemented for SE OU 10 and the most recent sampling event was conducted in August 2007.

SE OU 11 – NSIA VOC-Contaminated Groundwater North of Gate 6

SE OU 11 consists of the VOC-contaminated groundwater associated with the IWTP lagoons and IWWS gravity lines. The groundwater discharges off-post (see SE OU 6). A pilot study was initiated in September 2001 to evaluate the feasibility of treating DNAPL sources and reducing off-site contaminant migration concentrations at the property line. This study was completed by January 2003. Additional investigations to verify the vertical extent of groundwater contamination were conducted from 2005 to 2006. The results of the additional investigations will be reported in a focused feasibility study (FFS).

A vapor intrusion pilot study was conducted from July 2004 to January 2006, and a draft report is currently being revised to address regulatory comments. The Work Plan for the Evaluation of the Vapor Intrusion Pathway at SE OUs 6 and 11 was finalized June 2007. Vapor intrusion sampling will be conducted in the winter of 2007 and in the spring/early summer of 2008. The FFS Draft Report is expected to be produced in 2007.

SE OU 12 – Landfill G

The LEAD Installation Assessment identified this area as active from 1964 through 1978, when it was leveled to match the existing terrain. The area was used to dispose of residue from nearby trash revetments and IWTP sludge. Visibly contaminated leachate (metals) was reported to emanate from this site into a nearby drainage ditch. A 1991 SI identified several magnetic anomalies, which were cross trenched in 1993. All anomalies were related to drums that were buried and formerly contained caustics. Sampling indicated that these buried drums had caused no environmental problems. Another anomaly showed a large number of solvent containers, which were drummed and disposed of in this area. This site consists of contaminated soil, groundwater, and surface water. The 1995 SI follow-on identified this site as requiring a Remedial Investigation (RI). A Work Plan for the RI was finalized in June 2006.
The initial round of the RI field work was completed in July 2006. The test trenching conducted during the RI showed that primarily municipal-type waste is present in the landfill. The analytical results for the RI indicated that additional test trenching, soil sampling, and analysis needed to be conducted to further assess elevated levels of PCBs. The additional site investigation work was conducted in July 2007. Containers of black tar-like substance, thought to be discarded adhesive material, were encountered during the second round of the RI. The material had a petroleum-like odor. The size of the area where the containers were found is approximately 10 ft by 15 ft and 6 ft deep. The containers were encountered at about 4 ft below ground surface and the depth of the affected area did not extend beyond 6 ft deep. The preliminary analytical results show that contaminants of potential concern are benzene, lead, zinc and 2-methylphenol. A removal action was completed in January 2008 - the action removed the containers, associated waste and affected soils.

SE OU 13 – Southern Martinsburg Shale Region Groundwater

SE OU 13 encompasses BRAC property. The Southern Martinsburg Shale Region (SMSR) is a region at LEAD that contains an area of shale bedrock surrounded by downgradient limestone bedrock. This shale bedrock is generally more resistant to weathering than the surrounding limestone formations and therefore, forms the “highland” or elevated ridges within the Phase III parcel areas. Several groundwater and surface water divides along this ridge in the SMSR cause groundwater to flow away from the SMSR.
The SMSR was originally considered to be part of VOC-contaminated groundwater SE OU 10 and SE OU 11. Based on its geologic and topographic setting, it was thought that the SMSR would be unaffected by the known and potential VOC sources located downgradient of the SMSR because groundwater flows from the SMSR into the lower lying valley areas underlain by limestone. Therefore, a groundwater investigation was initiated in 1999 to establish that the SMSR was not impacted by any previous industrial activities at Letterkenny. The results of four rounds of groundwater sampling, conducted in late 1999 through 2000 and in 2002, showed no VOC groundwater contamination in the SMSR. Based on this finding, the SMSR was redefined as SE OU 13, and a no further action ROD was signed for SE OU 13 in August 2003. SE OU 13 was part of the Phase III BRAC property transfer completed in January 2004.

SE OU 14 – Former Test Track Area

SE OU 14 was created in 2007 to track sites in Army-retained land that were formerly administered under the BRAC program and are now in the ER,A program as a result of the revised BRAC boundary. SE OU 14 consists of the Former Test Track in the Disposal Area, Areas E and F, and the Building 349 Soil Staging Area. The RI/RA for the Former Test Track and Areas E and F was finalized in 2004. This RI/RA showed that risks are within acceptable levels for commercial/industrial use. A RI was also conducted for the Building 349 Soil Staging Area and a report was drafted in 2003.

The Army also formed a Restoration Advisory Board (RAB) with the regulators, citizens and local government members to give input to final cleanup decisions. Funding for cleanups comes from both Army BRAC and Installation Restoration Programs accounts. Further study is also needed for additional transfer of BRAC parcels, including possible transfers prior to final cleanup.

Contacts

Site Contacts

Administrative Record Locations