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' A minor amount of additional over-excavation was conducted on January 7 and 11 , 1993 to remove soil determined to contain elevated levels of TPH-G from the west and southwest sides of the UST excavation Additional confirmation soil samples were obtained from the excavation and submitted to Chromalab, Inc , a state of ' California-certified laboratory in San Ramon, California The maximum depth of the ' excavation was approximately 12 feet below the ground surface (bgs) in the immediate area around the former USTs and the southeast quarter of the excavation ' The depth to groundwater during the excavation activities was approximately 9 5 feet bgs ' Figure 3, Soil Sample Location Map, illustrates the final extent of the excavation around the former USTs Field observations and PID measurements of the sods as they were being removed from the excavation were used to identify areas containing ' residual hydrocarbons Confirmation soil samples were then obtained from these areas with a hand operated core sampler for laboratory analysis The analytical results of the confirmation samples obtained from the excavation are presented in Table 2 (samples SW-2, SW-4, SW-5, SW-9 through SW-11 , PB-1 , and PB-2) The final ' confirmation soil samples listed in Table 2 are presented in the shaded rows and in bold type The other samples were from areas that were removed during further excavation Based on the field observations and the results of the confirmation soil sample results, the majority of the hydrocarbon affected-soil above the water table ' was removed In addition, the heavily affected soil to approximately 2 to 3 feet below the water table was also removed during the excavation The groundwater present in the UST excavation contained a partial hydrocarbon sheen on its surface Therefore, immediately prior to the backfilling of the excavation approximately 1 ,320 gallons of groundwater were pumped out of the pit While ' pumping water out of the excavation, a device was used which allowed the sheen to be skimmed off the surface of the water The water was pumped directly into two /"iftelhauser C 0 R P O R A T 1 0 N P2188R006 wP{031941 4