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' OES-Idlewild Market September 26,1994 Page-4- ' 6 0 RESULTS OF ANALYSES Laboratory analyses of the soil samples collected from SB 1 and SB2 at depths of rapproximately 15 and 20 feet below the ground surface indicated no evidence of the hydrocarbon constituents analyzed for at the reported laboratory detection limits Additionally, field screening with ' the OVA-FID Indicated no evidence of petroleum hydrocarbons in any of the soil samples collected from SB 1 and SB2 1 7.0 CONCLUSIONS AND RECOMMENDATIONS ' Field observations made during the over-excavation and the installation of SBI and SB2 indicated a continuous layer of silt-pan was present in the area of Pit 1 from approximately 6 feet to 11 feet below the ground surface Light- to medium brown sand, with minor amounts of silt was present beneath the silt-lean Laboratoryanalyses of the soil samples collected from SB 1 and SB2 at depths of Y P P Iapproximately 15 and 20 feet below the ground surface indicated no evidence of the hydrocarbon constituents analyzed for at the reported laboratory detection limits Additionally, laboratory analyses of soil samples collected beneath the silt-pan from a depth of 12 to 17 feet below the ground surface following the tank removal and over-excavation indicated no evidence of petroleum containmation at Ithe reported laboratory detection limits The source(s) of contamination (the USTs) have been removed from the site Condor estimates that a small volume of approximately 6 to 7 cubic yards of contaminated soil is present from a depth of 6 to I I feet beneath the south end of the canopy foundation at Idlewild Market The results of laboratory analyses of the soil sample collected beneath the former location of T2 at a depth of approximately 12 feet below the ground surface, in addition to soil samples collected from the floor and south, east and west sidewalls of Pit I following over-excavation, indicate that the vertical migration of the contaminates has not extended below a depth of 12 feet Phis conclusion is supported by field observations (staining, petroleum odors and OVA measurements) and the results of laboratory analyses of soil samples collected from angle borings drilled beneath the canopy foundation In addition, the small volume of contaminated soil is located beneath the concrete canopy foundation The concrete foundation will limit infiltration and subsequent migration of surface water through the fvadose zone and thereby decrease the potential for mobilization of contaminates • k CONDOR