Site 5 - Transformer Storage Boneyard
This site was the primary storage area for out of service transformers, (including PCB-containing transformers) from 1945-1985. According to the 1986 IAS, at least six transformers reportedly containing PCB oils were stored between 1979 and 1981 on the basement floor level of Building 226. This building has since been razed. In 1981, while the transformers were reportedly stored in the building, vandals removed the tops from six of them, spilled the contents onto the floor and stripped out the copper cores. The entire contents of the transformers (approximately 132 gallons of oil) were reportedly lost into the soil of the 100 square-foot storage area. Site conditions determined from the IAS indicated that there was a potential for soil contamination as a result of the spill, and also a potential for contaminant migration and exposure by potential receptors.
A RI Verification Step was conducted in 1991 to collect and analyze soil samples to verify the presence of PCB’s (if any) at the site; to determine the approximate degree of contamination (if present); and to plan an extended monitoring program (if required) or recommend no further action if PCB’s were not found.
According to the IAS, no cleanup of the site was conducted. The transformers were removed in 1985 and the area is currently used for road maintenance storage.
Soil sampling at the Mainside Transformer Storage Area was conducted in two phases, the first taking place in September 1987 and the second in June 1988. The results of sampling and analysis indicated that no PCB contamination of shallow soil occurred in the vicinity of and downgradient of Building 226; and that any contaminated soil had eroded or otherwise been removed, so that no residual contamination remained in the shallow soil of the area sampled. This included the area of the interior floor of the Building 226 basement where the spill reportedly occurred.
A RI conducted in 2010 and 2012 investigated soil and groundwater at Site 5. Using data from the 2010 and 2012 investigations, a risk assessment identified unacceptable risk under future residential and industrial/commercial land use scenarios from exposure to PAHs and several metals in soil, and one VOC and several metals in groundwater. Concentrations of PAHs in soil exceeded criteria protective of industrial/commercial and construction workers.
The Site 5 ROD was signed in 2014 which documents a remedy of LUCs to prevent exposure to contaminated soil and prevent groundwater use as a potable source. LUCs were implemented in May 2016 to restrict future use of the site, prohibit installation of groundwater wells other than for environmental sampling, and require annual inspections of the site to make sure LUCs are continuing to be implemented.
Previous investigations, plans and documentation at this site are: IAS; RI/RA; FS; PP; and a ROD.
LUCs have been implemented.