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Site 1: Fire Training Area
The former Fire Training Area (FTA) is an open field and wetlands area approximately 10.3 acres in size and located on the northern portion of Cutler’s VLF Area, north of the VLF antenna arrays. The former FTA is surrounded on all sides by undeveloped forested land with several freshwater wetlands (known locally as heaths) located nearby.
Historically, the former FTA is located within a former gravel burrow pit that was used by the Navy for firefighting training exercises from the early 1960s into the 1980s. These fire training exercises reportedly used two 4,200-gallon capacity tanks that were partially filled with water and topped with waste oil from the power plant. This oil was ignited for the training exercise. During the training exercises, as well as during rain and snow events, the two tanks would fill with water and overflow, releasing waste oil into the environment. Additionally, when the power plant switched from No.6 fuel oil to No.2 fuel oil in about 1980, the remaining No.6 fuel oil was reportedly removed from the three tanks at the power plant and spread on the ground at the former FTA.
In 2006 during the NTCRA, seven buried drums were identified and removed from the southwestern portion of the former FTA site. This Drum Disposal Area (DDA) was later surveyed using geophysical equipment to search for additional buried drums. In 2009, an additional 33 buried drums, scrap metal, and contaminated soils were excavated and removed for disposal. In 2010, additional soil sampling found PCB contamination at the DDA. Also in 2010, the DDA was designated as Site 5, and in 2012, the DDA (Site 5) was combined with the former FTA (Site 1) due to their geographical proximity and similar contaminants. As a results, Site 5 was closed and all contamination associated with Site 5 is being addressed as Site 1 (FTA).
In 2012, another geophysical survey located more metal anomalies with one additional buried drum being discovered, excavated, and removed from the DDA. In 2013, the Navy conducted additional cleanup and removal activities at the DDA. These activities were accomplished in two separate phases. The first phase of work involved drum removal and excavation of contaminated soil. A total of 35 buried drums, several crushed drums, some scrap metal, and two stockpiles (371.77 tons) of contaminated soil were excavated from the DDA. Also, post-excavation soil samples were collected and analyzed. The second phase of work involved the loading, transportation, and disposal of the contaminated soil and restoration of the DDA. A follow-up geophysical survey performed in 2013 found no additional buried drums or metal debris. This second phase of work was completed in November 2013. Environmental sampling detected soil and groundwater contamination. In response, the Navy conducted several investigations and several cleanup removal actions at the former FTA. In the fall of 1999, approximately 4,700 tons of petroleum contaminated soil were excavated and removed from this site. In 2001, a follow-up groundwater investigation was conducted at the former FTA. Between 2006 and 2009 a Non-Time Critical Removal Action (NTCRA) was performed to remove contaminated soil. During the NTCRA, approximately 24,000 cubic yards (31,200 tons) of petroleum-contaminated soil were excavated and transported to a landfill for disposal, approximately 1.8 million gallons of surface water were treated and release to infiltrated back into the ground, and seven buried drums and some scrap metal were discovered and removed from the site. In 2009, the excavated area was backfilled with clean soil and restored to a self-sustaining upland freshwater wetland (heath) using native vegetation. In 2010, after site restoration, the Navy evaluated residual levels of contamination in the soil and groundwater and estimated their potential human health and ecological risks. The risk evaluations concluded that after completing the NTCRA, no further soil removal was necessary. The risk evaluation of contaminant levels in the groundwater indicated that residual levels are within acceptable levels for current and foreseeable future uses, but that potential risks associated with potential future residential use may be above acceptable levels. The remedy for the remaining soil and groundwater contamination was determined to be monitored natural attenuation. Until the site is fully restored, land-use controls will most likely be established to restrict site usage. The former FTA site will continue to be monitored until soil and groundwater are cleaned up by natural attenuation to levels acceptable for unrestricted site use.
The Navy characterized the nature and extent of contamination in soil and groundwater at the Former FTA (Site 1) and completed a Remedial Investigation in 2017. The Feasibility Study, conducted to develop and evaluate soil and groundwater remedial alternatives, was based on the RI, and also completed in 2017. The Navy’s preferred alternative to address contamination was presented in a 2018 Proposed Plan. A public meeting to present the Proposed Plan was held on September 26, 2018, at the Bay Ridge Elementary School in Cutler, Maine. The selected remedy (soil excavation and off-site disposal, groundwater monitoring, and land use controls for Site 1 was documented in the Record of Decision signed in November 2019. A Remedial Design document was completed in September 2019. The Site 1 remedial action is planned for 2020-2021.
Site 2: Salvage Yard Area
The Salvage Yard Area (SYA) is a grass and gravel-covered area approximately 7.01 acres in size and located on the northern portion of Cutler’s VLF Area, north of the VLF antenna arrays and east of the former FTA site. Approximately 0.44 acre of the 7.01-acre site consists of wetlands along the northern boundary of the SYA. Thick vegetation including trees and shrubs are present to the east, west, and south of the SYA.
The SYA was historically used as a temporary repository and storage location for materials and wastes awaiting off-site transport. Materials stored at the SYA included scrap metal, batteries, and other recyclable materials. Wastes stored at the SYA included lube oil, mercury, electronic equipment, batteries, asbestos, Cadweld powder (used for welding), and 55-gallon drums of solvents.
The SYA was initially investigated in 1991 as part of a Site Inspection (SI), which included field radiation screening, a soil vapor survey, soil borings, and installation of four monitoring wells (MW-5 through MW-8). The details of the SI results can be found in the 1994 SI Report located online in the Administrative Record. Petroleum hydrocarbons, PCBs, and chlorinated solvents were detected in the soil and groundwater samples collected from the SYA during the SI. The SI report recommended that test pits be dug to investigate underground anomalies that were identified during a geophysical survey and to include additional soil and groundwater sampling to further characterize the nature and extent of contamination.
In late 1999, several test pits were excavated to locate and remove buried materials and to collect soil samples. Buried materials encountered during test pitting were removed from the site and disposed of off-site. Materials removed from the SYA in 1999 included asbestos transite panels, empty drums, storage containers, steel cable, and office furniture. Also during the 1999 test pitting activities, a buried office trailer was discovered that contained paint cans and some miscellaneous materials.
During the summer of 2000, the remains of the buried office trailer were excavated and removed from the site and additional test pitting was performed throughout the SYA to look for any additional buried material and to visually inspect the soil for contamination. As a result of the 2000 test pitting activities, contaminated debris and soil were removed from the SYA during separate removal and disposal events in 2001 and 2002. Post-excavation sampling results revealed that concentrations of PCBs, petroleum hydrocarbons, and heavy metals remained in soils above the removal action cleanup levels and that additional soil and groundwater sampling was warranted.
In 2006, soil borings and monitoring well installation activities were completed with the objective of finishing the site characterization study for this site. The data collected during the 2006 investigation defined the extent of contamination in soil; however, additional sediment and groundwater investigations were recommended. Also, a geophysical survey performed in 2006 identified additional areas to the west and south that appear to have been used for the temporary storage of materials awaiting off-site transport and disposal. An additional subsurface investigation in these areas was recommended
In late 2010, an additional soil investigation was performed in the area south of the original limits of the SYA to evaluate the presence and nature of contaminants in soil where metal debris was found during the 2008-2009 test pitting activities. In 2011, a PCB soil removal action was conducted. In 2012, a geophysical survey and test pit program were performed to further investigate the SYA for the presence of buried debris. Additional metal and other debris including wire, roofing material, concrete, and sheet metal were observed in the test pits and removed from the site. In 2015, groundwater sampling activities were conducted at the SYA to provide additional data for the Remedial Investigation. In 2008, a hydrogeological investigation was performed to determine the extent of solvent contamination (i.e. trichloroethene (TCE) and tetrachloroethene (PCE)) in the groundwater and to conduct additional sediment sampling along the north boundary of the site. A geophysical survey and test pitting in the western and southern areas were also performed during the 2008 investigation which continued into 2009. After the 2008-2009 investigation, the extent of groundwater and sediment contamination, as well as the extent of debris to the west and south, had been adequately defined.
In summary, several environmental investigations and interim removal actions have been performed at the SYA between 1991 and 2015 to address contamination including geophysical surveys, test pitting, limited soil excavation, off-site disposal, and soil, sediment, surface water, and groundwater sampling. In addition to a few remaining areas of soil contamination, two separate areas of groundwater contamination exist at the SYA. One area is primarily composed of TCE and located beneath the western portion of the site. The second area is primarily composed of PCE and located beneath the eastern portion of the site. Groundwater sampling events conducted from 2002 to 2015 have defined the nature and extent of the groundwater contamination. The groundwater data over time indicates that both the TCE and PCE areas are not migrating and concentrations show stable to decreasing trends.
The Navy characterized the nature and extent of contamination in soil and groundwater at the Salvage Yard Area (Site 2) and completed a Remedial Investigation in 2017. The Feasibility Study, conducted to develop and evaluate soil and groundwater remedial alternatives, was based on the RI, and also completed in 2017. The Navy’s preferred alternative to address contamination was presented in a 2018 Proposed Plan. A public meeting to present the Proposed Plan was held on September 26, 2018, at the Bay Ridge Elementary School in Cutler, Maine. The selected remedy (soil excavation and off-site disposal, in-situ treatment of trichloroethene (TCE) in groundwater with monitored natural attenuation, and land use controls for Site 2 was documented in the Record of Decision signed in November 2019. A Remedial Design document was completed in September 2019. The Site 2 remedial action is planned for 2020-2021.
Site 3: Construction Debris Area
The Construction Debris Area (CDA) is approximately two acres in size and located on the northern portion of Cutler’s VLF Area, north-northwest of the VLF antenna arrays and west of the former FTA site. The CDA is a cleared and undeveloped area bordered by woods to the south, east, and west and by a gravel road to the north. The CDA was used as a storage area for metal debris and other discarded materials. While the operational history of the CDA is unknown, it is presumed to have been used from the early 1960s to before 1998, when the area was first identified as an environmental site.
Between 1998 and 2011, the CDA was inspected, tested, cleaned, and closed to allow for unrestricted use. The initial Site Investigation (SI) was conducted in 1998. In 1999, two PCB-containing capacitors plus 11.27 tons of PCB-contaminated soil were removed from the CDA. Diesel-range organics, PCBs, arsenic, and lead were detected in post-excavation confirmation samples. An additional 17.6 tons of impacted soil were removed in 2000 with an additional SI being conducted in 2002 to define the extent of the impacted soil remaining at the CDA. Seven soil removal areas were excavated in October through December 2002; however, analytical test results indicated that cleanup criteria were not met at all of the removal locations. Additional soil was removed in June and July 2003.
In 2005, a human health risk screening evaluation was prepared to determine cumulative human health risks and to determine appropriate risk-based cleanup goals. Recommendations were made for the removal of soil from 12 discrete areas where residual contaminant levels exceeded the risk-based cleanup goals, and for the removal of debris that was present on bedrock outcrops in the southern portion of the CDA. Based on a residential human health risk scenario, three contaminants (PCBs, arsenic, and benzo(a)pyrene) were identified as the primary risk drivers. From April to November 2009, an additional 145.5 tons of soil were excavated and disposal of off-site. Confirmation samples revealed that benzo(a)pyrene remained in the soil at concentrations that exceeded screening criteria. These remnant benzo(a)pyrene-contaminated areas were excavated in September 2010 with post excavation sampling showing that the current site conditions were protective of human health and the environment.
After a series of removal actions, a No Further Action Decision Document was prepared and accepted by Maine DEP in 2011. The decision document summarizes the activities conducted at the CDA and the selected remedy which was no further action. The CDA was the first site at Cutler to be fully restored to unrestricted use and closed through the Navy’s ERP.
Site 4: Very Low Frequency (VLF) Peninsula
The VLF Peninsula is approximately 1,800 acres in size and occupies the southern portion of Cutler’s VLF Area. The VLF Peninsula is the location of the Cutler VLF transmitter which supports two VLF antenna arrays consisting of a northern array and a southern array. The panels in each antenna array are supported by 13 main towers to include a center tower surrounded by six inner ring towers and six outer ring towers. The main towers are approximately 800 to 1,000 feet tall. Each main tower is supported by one or two counterweights, which are each supported by a tower that is approximately 200 feet tall. The main towers and counterweight towers are coated with alternating bands of orange and white-colored paint.
As a result of the paint deteriorating by weathering processes over time, the towers have been repainted several times since their construction in the late 1950s. According to historical documents, the helix houses and towers were originally painted around 1960. Navy records indicate that the repainting of the towers occurred in 1967-1968 and again between 1980 and 1984. It was believed that PCBs improved the adhesive properties of the paint. During these historic repainting operations, paint chips were water-blasted and/or manually scraped from the towers and buildings. At the time, no effort was made to collect or contain the paint chips, as it was common practice. As a result of the paint removal activities and natural weathering over time, paint chips and particles have fallen to the ground surface of the VLF Peninsula.
In 1996, paint chip samples collected from the ground within the VLF antenna arrays were found to contain lead and PCBs. In 1997, the Navy began a construction project with the objective of removing lead- and PCB-laden paint and repainting them with contaminant-free orange and white-colored paint. During this repainting project, collection and containment systems were used to minimize the release of paint chips and particle to the environment. This construction project was completed in 2008.
In 2006, the Navy, Maine DEP, and U.S. Environmental Protection Agency (USEPA) evaluated various methods for soil sample collection and processing that would meet the objectives of characterizing the nature and extent of contamination and assess the potential human health and ecological risks associated with the release of paint chips from the towers to the ground surface. In 2007 and 2008, a two-phase pilot study was performed in an effort to develop soil sample collection procedures that were appropriate to quantify contaminant concentrations in soils so that human health and ecological risk assessments could be prepared for Site 4. Phase I was conducted in 2007 to evaluate the feasibility of one particular soil sample processing method. Phase II was conducted in 2008 and 2009 to evaluate which types of sample collection and processing approaches would be most effective in producing data with an acceptable level of variability to support the Remedial Investigation. In 2009, the Remedial Investigation Work Plan was developed.
In 2010, the Remedial Investigation field work began. Surface and near surface samples were collected. Each soil sample consisted of a five-point composite sample. Soil and sediment samples, and a few terrestrial biota (earthworm) samples, were collected for laboratory testing. These sampling efforts were designed to characterize the nature and extent of paint chip-related contamination at the towers, in nearby streams, in wetland areas, and along the shoreline of the VLF Peninsula. In addition, sediment and biota samples were collected from two background reference locations west of the VLF Peninsula.
As described above, numerous environmental investigations have been performed for the VLF Peninsula. The primary concern at Site 4 is the release of paint chip-related contamination to include PCBs and lead). The Navy characterized the nature and extent of contamination in soil at the VLF Peninsula (Site 4) and completed a Remedial Investigation in 2016. The Feasibility Study, conducted to develop and evaluate soil remedial alternatives, was based on the RI, and completed in 2017. The Navy’s preferred alternative to address contamination was presented in a 2018 Proposed Plan. A public meeting to present the Proposed Plan was held on September 26, 2018, at the Bay Ridge Elementary School in Cutler, Maine. The selected remedy (soil vacuum excavation with off-site disposal and land use controls for Site 4 was documented in the Record of Decision signed in November 2019.
After observing the Site 7 South Helix House remedial action (soil excavation with off site disposal) in October and November 2019 and additional discussions with facility and operational staff regarding excavation on the VLF Peninsula, an Explanation of Significant Difference (ESD) was completed to modify the remedy from soil excavation and backfilling to the installation of a protective soil cover to prevent exposure to contaminated paint chips and soil at the ground surface. The ESD was signed in April 2020. A draft Remedial Design document was also completed in April 2020. The Site 4 remedial action is planned for 2021-2022.
Site 5: Drum Disposal Area
The Drum Disposal Area (DDA) is located on the southwestern portion of Site 1, the former Fire Training Area (FTA), and approximately one-quarter mile north of the VLF antenna arrays. The DDA and FTA are located in a former gravel burrow pit that was used for firefighting training activities which reportedly began in the late 1950s and continued until the late 1980s. The DDA was discovered in 2006 during site preparation for a soil removal action at the former FTA. While grading the site to establish a staging area for treatment equipment, seven buried drums were encountered in an area separate and distinct from the FTA contaminated soil removal area. The drums were removed and a sample of oily product collected from the drums indicated that the substance in the drums contained petroleum hydrocarbons.
The DDA was initially investigated as AOC 31, since it was not immediately evident that the contamination present posed a significant threat to human health or the environment. During 2007 and 2008, AOC 31 was investigated to evaluate whether there were additional buried containers. Geophysical surveying and test pitting activities concluded that additional buried items were present and that further removal actions were warranted.
In 2009, an additional 33 buried drums, scrap metal, and associated contaminated soils were discovered, excavated, and removed from the DDA. After the removal of soil in 2009, soil disposal samples and excavation sidewall and bottom samples were collected for laboratory testing. These samples revealed the presence of PCBs. Based on the 2009 soil sampling data, the vertical and horizontal extent of PCB contamination was not defined, so a work plan for delineation was developed. As a result of discovering PCBs, the Navy elevated AOC 31 to Site 5 in 2010. Also in 2010, a soil investigation to delineate the horizontal and vertical extent of PCBs was completed at the DDA in order to estimate the volume of contaminated soil for an additional soil removal action. As noted in the site description for the former FTA, a geophysical survey conducted in 2012 located additional metal anomalies. One additional drum was discovered, excavated, and removed from the DDA in 2012.
In 2013, the Navy conducted cleanup and drum removal field activities at the DDA. The field activities were accomplished in two separate phases. The first phase of work involved drum removal and excavation activities. A total of 35 buried drums, several crushed drums, some scrap metal, and two stockpiles (371.77 tons) of contaminated soil were removed from the DDA. In addition, post-excavation soil samples were collected and analyzed for PCBs. The second phase of work involved the loading, transportation, and disposal of soil, and restoration of the DDA. In addition, a follow-up geophysical survey performed in 2013 found no additional buried drums or metal debris. This second phase of the work was completed in November 2013.
For additional details regarding the DDA, refer to Site 1, the former Fire Training Area’s site description. Site 5 was closed in 2012, but a closure letter was not provided at that time. Based on historical information that was provided in a Summary Memorandum for Basewide Areas of Concern and Sites report dated June 6, 2016 and the submittal of No Further Action Concurrence Request letter from the Navy dated July 19, 2016, the Maine DEP agreed with no further action for Site 5 in a letter dated August 1, 2016 and Site 5 was closed.
Site 6: Fire Training Area (FTA) Access Road
The FTA Access Road is a gravel road that was historically used to access the former FTA (Site 1). A significant portion of this road is still passable by vehicle, but the last several hundred feet of roadway have been overgrown by vegetation and is no longer accessible to vehicle traffic.
In 2006, one abandoned 55-gallon drum was discovered by Cutler personnel in the woods located approximately 100 feet south from a hilltop clearing at the end of the old access road to the former FTA. The closed-top drum was found empty and on its side. The drum had a slight petroleum odor and stained soil was observed on the ground surface beneath the drum. A hole in the drum had allowed rainwater to accumulate inside. The drum contents were sampled prior to disposal. The drum contents were characterized as non-hazardous and the drum was placed in an over-pack container and removed from the site.
In 2007, the Navy conducted a soil and groundwater investigation to evaluate the presence and nature of contamination and to determine whether the drum’s spilled contents resulted in contamination that might present a risk to human health or the environment. Soil samples were collected at the drum location and one monitoring well was installed as part of the environmental study. Laboratory testing detected petroleum and metals in the soil and groundwater.
In 2009, eight additional surface soil samples were collected and tested for contamination. Based on the results, AOC 32 was elevated to Site 6 in 2010; however, no contaminants were found above screening or background levels. The 2009 Site Investigation Report recommended no further action for soil and groundwater.
In December 2010, Maine DEP agreed with the recommendation of no further action; however, a no further action letter was not provided at that time. Based on historical information that was provided in the Summary Memorandum for Basewide Areas of Concern and Sites report dated June 6, 2016 and the submittal of a No Further Action Concurrence Request letter from the Navy dated July 19, 2016, the Maine DEP agreed with no further action for Site 6 in a letter dated August 1, 2016 and Site 6 was closed.
Site 7: South Helix House
The South Helix House (SHH) is located at the center of the southern VLF antenna array on the VLF Peninsula. According to historical records, a spill occurred from an electrical transformer switch located inside the Hoist Transformer Room (HTR) in the early to mid-1980s. The HTR is located in the southeastern portion of the SHH building complex. An estimated volume of 40 to 50 gallons of PCB-laden dielectric oil spilled onto the floor and walls of the HTR. The spill traveled through the doorway of the HTR and along the southwest wall of the HTR. Historical data indicates that the oil migrated downward through the soil to varying depth and was also tracked across the ground surface to the east and south away from the spill area.
In October 1999, the Navy conducted an investigation of the soils impacted by a spill of dielectric oil containing PCBs. The horizontal and vertical extent of PCB contamination was evaluated by collecting soil samples in a grid pattern spanning the presumed limits of the spill area. The results from this investigation determined that in most of the shallow soils (0 to 1 foot) sampled, PCB concentrations exceeded screening levels. Where soil samples were collected from the 0 to 1 foot depth interval exceeded screening levels, a soil sample was collected from the 1 to 2 foot depth interval for field screening and potential laboratory analysis. This approach to delineation was repeated to a depth of up to 8 feet throughout the investigation area.
In November 1999, an interim soil removal action was completed at the SHH. The removal action consisted of excavating PCB-contaminated soil to a depth of approximately 2 feet. Approximately 19.9 tons of contaminated soils were excavated and transported off-site for disposal. A layer of polyethylene sheeting was placed in the excavation before it was backfilled in order to separate clean backfill from underlying contaminated soil. The excavated area was restored to grade with stone. Confirmatory soil sampling was not conducted during this interim removal event.
A second removal action was performed during the summer of 2000. This removal action consisted of excavating contaminated soil to a depth of up to 5 feet throughout the spill area. The first stage of excavation resulted in the removal of 49.16 tons of soil. After soil removal, 21 confirmation soil samples were collected to evaluate PCB concentrations remaining in the soil. Laboratory test results revealed that several sample locations exceeded the screening criteria. A second soil excavation event was performed to remove soils containing greater that the interim cleanup criteria. During this second event, 31.96 tons of soil were excavated and removed from the site and a second round of confirmation samples were collected on September 6, 2000. The analytical test results revealed that soils exceeding the cleanup criteria remained at the site.
In 2010, additional surface soil sampling was performed to determine the horizontal extent of the remaining PCB contamination. The horizontal extent of contamination was defined; however, the vertical extent of contamination next to the HTR was not defined. Due to the presence of facility structures, not all of the PCB-contaminated soils could be defined beneath the site. Subsequently, the vertical extent of subsurface soil contamination adjacent to and possibly beneath the HTR could not be determined and will remain in place until such a time when access to these soils is provided.
Based on evaluations of soil data collected at the SHH, it appears that physical migration of the PCB-laden oil occurred from the spill area to the perimeter gravel access road as a result of pedestrian traffic and activities such as snow management. The Navy characterized the nature and extent of contamination in soil at the the South Helix House (Site 7) and completed a Remedial Investigation in 2016. The Feasibility Study, conducted to develop and evaluate soil and groundwater remedial alternatives, was based on the RI, and completed in 2017. The Navy’s preferred alternative to address contamination was presented in a 2018 Proposed Plan. A public meeting to present the Proposed Plan was held on September 26, 2018, at the Bay Ridge Elementary School in Cutler, Maine. The selected remedy (soil excavation with off-site disposal and land use controls) for Site 7 was documented in the Record of Decision signed in August 2019. A Remedial Design document was completed in January 2019. Field activities for the remedial action were performed in October and November 2019. Approximately 276 cubic yards of PCB-impacted soil and 468.5 cubic yards of PCB-impacted gravel were vacuumed excavated and disposed of off-base. Confirmation samples were tested and the excavations were backfilling. A Construction Completion Report is being prepared and will summarize the remedial action.
Site 8: Maintenance Building and Shed
The Maintenance Building and Shed area is approximately 3.3 acres in size and located on the northern portion of Cutler’s VLF Area, north-northeast of the VLF antenna arrays near the front gate. The maintenance building (Building 132, also known as the “Boathouse”) is currently used for the storage of construction materials and tools necessary for facility maintenance. Historically, another building was located at the current Building 132 location. This former building was used for the storage of clay pigeon targets used at the former skeet range. Two other maintenance buildings are located in the vicinity of Building 132 and several contractor trailers also exist nearby. A sanitary leach field, a ravine, a drinking water well, and paved and unpaved access areas are also located within the Maintenance Building and Shed area.
The Maintenance Building and Shed area is approximately 3.3 acres in size and located on the northern portion of Cutler’s VLF Area, north-northeast of the VLF antenna arrays near the front gate. The maintenance building (Building 132, also known as the “Boathouse”) is currently used for the storage of construction materials and tools necessary for facility maintenance. Historically, another building was located at the current Building 132 location. This former building was used for the storage of clay pigeon targets used at the former skeet range. Two other maintenance buildings are located in the vicinity of Building 132 and several contractor trailers also exist nearby. A sanitary leach field, a ravine, a drinking water well, and paved and unpaved access areas are also located within the Maintenance Building and Shed area.
Site 8 was identified in the 2007 PSA Report as AOC 9. Initially, there was suspicion that buried drums were located behind (north of) the Maintenance Building and Shed area. It was also thought that solvents, pesticides, and herbicides were released into the environment through an on-site underground septic system and leach field that serves the Maintenance Building. In addition, historical records from 1992 indicate that approximately 400 gallons of fuel oil were spilled onto the ground during a tank removal project and that the spill was cleaned up.
In 2007, soil, groundwater, and geophysical investigations were performed around the Maintenance Building and Shed area to evaluate the presence and nature of contamination in order to determine whether historical activities resulted in contaminant levels that might present a risk to human health or the environment.
In 2009 and 2011, field investigations, test pitting, and two removal actions were performed at the Embankment Debris Sub-Area (ravine) and at the Northeast Geophysical Anomaly Sub-Area (septic field) located to the north of the Maintenance Building. Empty drums, empty containers, and other metal debris were found in the ravine behind the Maintenance Building and Shed area. In addition, four groundwater monitoring wells were installed at Site 8. Laboratory testing of soil and groundwater samples collected during these investigations detected just a few contaminants above screening criteria.
Based on the detection of contamination above screening criteria during the initial investigations, AOC 9 was elevated to Site 8 in 2010. However, due to the relatively low levels of contamination, the completion of two removal actions, and performance of geophysical surveys, Site 8 was recommended for no further action. Based on historical information that was provided in the Summary Memorandum for Basewide Areas of Concern and Sites report dated June 6, 2016 and the submittal of No Further Action Concurrence Request letter from the Navy dated July 19, 2016, the Maine DEP agreed with no further action for Site 8 in a letter dated August 1, 2016 and Site 8 was closed.
Site 9: Dirt Roads
The Dirt Roads area consists of 1.4 miles of gravel roadway located on the northern portion of Cutler’s VLF Area, immediately north of the VLF antenna arrays between the Maintenance Building and the Power Plant. The concern for this site was the spreading of waste oil, possibly containing PCBs, for dust suppression. According to former Cutler personnel, the waste oil was reported to have been lubrication oil originating from the generators located at the Power Plant. The duration of these oil-spreading activities and volume of oil applied are unknown.
In 2007 and 2009, field investigations were performed along the extent of the dirt roads to evaluate the presence and nature of contamination and to determine if historical activities resulted in contaminant levels that might present a risk to human health or the environment.
During the investigations, a total of 22 soil samples and two surface water samples were collected and tested for PCBs, metals, and petroleum. PCBs were detected, but at concentrations below screening criteria. Metals were generally within the range of background concentrations. Petroleum constituents were detected, but below screening criteria. PCB and petroleum concentrations were not detected in the two surface water samples. The metals detected were essential nutrients and included calcium, magnesium, potassium, and sodium. The detected PCBs appeared to be paint chip related and will be addressed with paint-related contamination across the VLF Peninsula as part of the Site 4 investigation.
Given the relatively low concentrations of PCBs, metals, and petroleum, the 2010 Site Investigation report recommended no further action. However, the Dirt Roads area was elevated from AOC 13 to Site 9 in 2010. At the conclusion of the 2010 SI Report, no further action was recommended, but a closure letter was not provided at that time. Based on historical information that was provided in the Summary Memorandum for Basewide Areas of Concern and Sites report dated June 6, 2016 and the submittal of No Further Action Concurrence Request letter from the Navy dated July 19, 2016, the Maine DEP agreed with no further action for Site 9 in a letter dated August 1, 2016 and Site 9 was closed.
UXO 1: Former Skeet Range
The Former Skeet Range is located on the northern portion of Cutler’s VLF Area, north-northeast of the VLF antenna arrays and east of Site 2, the Salvage Yard Area. The exact dates of operation are unknown. Interviews with installation personnel indicate that the Former Skeet Range was constructed prior to 1990. The Former Skeet Range was temporarily shut down in 1990 and reopened for about one year in 1995. The Former Skeet Range was only used for recreational purpose and was not used for training.
Wetlands, thick vegetation, moss, and root mat layers cover the majority of shooting range. There is no historical or physical evidence of the types of munitions that were used, but the type of shooting range (skeet) indicates that the munitions would likely have included small arms ammunitions such as shot gun ammunition (e.g., 12 gauge). The primary munitions constituent (MC) of concern at the Former Skeet Range is a release of metals (primarily lead) associated with lead shot. Although not considered a MC, polycyclic aromatic hydrocarbons (PAHs) associated with clay pigeon debris may also be present as a result of the skeet shooting activities. In general, clay pigeon debris can typically be found within 75 to 100 yards of their launch location. No evidence of clay pigeon debris was noted in the 2009 or 2011 field notes. However, a few clay pigeon fragments were seen in the vicinity of one of the skeet launching houses in 2016. In June 2017, these fragments were manually collected, containerized, and disposed of at a landfill. Given the extremely low quantities of clay pigeon debris observed and the reported limited use or the range, impacts associated with PAHs were not detected.
Several investigations have been performed to address potential environmental contamination. In 2007, a Preliminary Site Assessment (PSA) was performed. According to the PSA, soils on the skeet range were suspected to be impacted from past shooting activities that involved the use of lead-pellet shotgun shells and that elevated lead concentrations may occur in surface soils. In 2009, surface soil samples were collected and tested for lead. In 2011, additional step-out soil samples were collected from select locations and tested for lead. Soil testing results revealed that several metals concentrations were detected above background and project screening levels. In 2016, additional soil samples were collected for lead and PAH testing in order to confirm the presence or absence of environmental impact from the former skeet range activities. Laboratory results revealed that detected metals concentrations appeared to be at background levels.
Based on field investigations, the laboratory findings, and the historical, infrequent use of the Former Skeet Range, no further action was recommended for the Former Skeet Range. A few clay pigeon fragments were observed in the vicinity of one of the skeet launching houses. These fragments were manually collected and containerized on June 21, 2017, and disposed of at a landfill the following month. Following the skeet fragment removal action, Maine DEP agreed that the site required no additional remedy. Site closure was approved by MEDEP by letter dated November 20, 2017.
Summary of Areas of Concern (AOCs)
In support of the Cutler ERP, numerous AOC investigations have been performed to address potential CERCLA contaminants identified at NCTAMS LANT Det Cutler. The following is a brief summary of this work. In addition, key reference documents are noted as pointers to additional detailed information that are available online in the Administrative Record.
In 2007, a Preliminary Site Assessment (PSA) was performed for the entire Cutler facility. This PSA report provides historical information on past operational and storage activities, site-specific data, historical sampling results, and identified 33 potential AOCs (Tetra Tech, Inc. 2007). During the fall of 2007 and summer of 2008, additional sampling events were performed at nine AOCs with their findings presented in a report titled Final Results/Recommendations of the AOC Site Investigation (Tetra Tech NUS 2009). During the fall of 2009, sampling was performed at four more AOCs and additional samples were collected at six previously investigated AOCs that were recommended for further investigation. The findings of this fall 2009 investigation are provided in a report titled Fall 2009 Site Inspection Report for AOCs (Tetra Tech NUS 2010). In 2011, additional sampling was performed at six other previously investigated AOCs. This 2011 sampling data was provided in a report titled Final 2011 Areas of Concern (AOCs) Investigation Transmittal dated April 21, 2014 (Tetra Tech NUS 2014). The 2011 sampling data along with other historical AOC data were used to prepare a report titled Areas of Concern Summary Memorandum dated December 2, 2014 (Resolution Consultants 2014). The purpose of this 2014 Summary Memorandum was to update the 2007 PSA recommendations and to provide a path forward for each AOC.
In 2016, a report titled Summary Memorandum for Basewide Areas of Concern and Sites dated June 6, 2016 (Resolution Consultants 2016) was submitted to Maine DEP. This report updated the 2014 Summary Memorandum and provided recommendations for all ten sites and 33 AOCs. In response to the June 2016 Summary Memorandum, the Maine DEP requested the Navy to prepare and submit a concurrence letter for AOCs that do not require further action. This letter, dated July 19, 2016, was titled No Further Action Concurrence Requests for AOCs and Sites (Navy 2016). As a result of submitting this July 2016 letter, the Maine DEP agreed with the recommendations of no further action for 30 of the AOCs. In addition, AOC 4 was provided with a no further action response in October 2016, AOCs 12 and 17 and UXO1 were provided with a no further action response in November 2017, and in July 2018, AOC 16 was retired by combined its contaminants into Site 4 as a result of being located in the same geographic area designated for remediation under Site 4.