Problems/Comments

The Shop Site is located north of the Copper River Highway along the road that passes through the quarters facility. There are a waste storage area, cistern, pumphouse, concrete pad, transformer, and a waste drum storage area at this site. Waste oil was stored in four or five 55-gallon drums near the southeast corner of the shop building for approximately 10 years. A pumphouse (Building 607) south of the shop contains a groundwater well and pump equipment. This well is approximately 30 feet deep. It serves facilities on the north side of the Copper River Highway. Six sumps were also believed to be situated west of Building 304. Sumps 1 and 2, constructed of buried, perforated, 55-gallon drums, were removed in 1995. Four additional sumps were suspected to be present. Upon excavation, a buried drum was found at Sump 3; no drums or dry wells were encountered at the remaining three locations. The sumps were abandoned by installing a plumber’s plug at either end and filling it with non-shrink grout at the sump end. Approximately 75 cubic yards of contaminated soil was excavated from the sump areas and thermally remediated in 1997. In 1994, three ASTs were addressed at the Shop Building #304. AST 35-E-1 was a 500-gallon, welded-steel tank north of the shop on a wooden frame used to store heating oil. Petroleum stains were evident on the ground surface at the former tank location. The probable sources of the staining include overfills and spills during fuel delivery. Approximately 1/8 cubic yards of potentially contaminated soil was excavated. A 1,000-gallon, welded-steel AST was formerly located west of the shop on a wooden frame. The tank was removed in 1994. On October 14, 1994, evidence was noted of a fuel release northwest of the shop which was associated with the 1,000-gallon AST. However, results of the field-screening and laboratory sample analyses at the former location of the 1,000-gallon AST did not indicate a fuel release. A 500-gallon AST temporarily stored northwest of the shop was removed before 1994. Field-screening sample results at the former AST location did not indicate a fuel release. In 1996, residual contamination at Drum Storage Area was DRO and RRO from composite samples of the floor and wall at 1,300 mg/kg and 2,400 mg/kg respectively. The remaining residual contamination is at least 5 feet above the estimated groundwater level. Residual contamination at Sumps 7 and 8 had DRO measured from the floor of the pit at 1,600 mg/kg (7’ bgs). Pipe extending southward from Sumps 7 and 8 is PVC of unknown length and destination. The depth of the pipe is approximately 5’ bgs. Additional investigation is recommended to determine the final discharge point and potential for downstream contamination. It is suspected that the pipe leads to a leach field. In 1996, based on confirmational sampling results, the sump areas to the west of Building 304 and the area north of the concrete pad have been restored to below action levels and do not require further action. Metals concentration results were consistently near background levels and do not warrant action. In July 1997, additional soil was excavated and confirmatory soil and groundwater samples were collected from the two areas: The Drum Storage Area and the former location of Sumps 7 and 8. Confirmation soil samples collected from both areas showed either non-detect or low levels of DRO. The highest level of DRO was 24 mg/kg

Action Information

Contaminant Information

Control Type

Requirements

No associated sites were found.