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excavation EXE 1 Soil samples were collected from the excavation side walls at depths of 8 feet bsg and a soil sample was collected from the floor of the southern most excavation (EXE I) at a depth of 8 feet bsg The analytical data indicated that the highest concentrations of TPH-g were in excavations EXE2 and EXE3 at the northeastern edge of the dispenser area,near well MW-2 TPH-g was detected in the eastern soil sample from excavation EXE2 at a concentration of 17,000 mg/kg TPH-g was also detected in the soil sample from the southern edge of excavation EXE3 at a concentration of 11,000 mg/kg BTEX compounds were detected at concentrations as high as 2,300 mg/kg The highest concentration of benzene, 15 mg/kg, was detected in the eastern sample from excavation EXE2/Fuel additives were detected samples from in excavations EXE2 and EXE3 TPH-d was detected in the soil samples from EXE2 and EXE3 that were also impacted with TPH-g and BTEX compounds Low concentrations of only TPH-d were detected in two soil samples from EXE1 The stockpile soil was impacted by low to moderate concentrations of petroleum hydrocarbons and fuel additives Soil from B-1,B-2, and B-7 at 15 feet bsg had low concentrations of hydrocarbons,while soil from B-1, B-6, and B-7 at 10 and 15 feet , B-2 at 10, 15, and 20 feet bsg had low concentrations of fuel additives(MTBE) Hydrocarbon impacted ground water wasQ e e teed a J3-1, B-6,B-7 and B-8 and MTBE was fly detected in grab ground water samples from-6 and -7 MTBE was detected by EPA method 8260 in all grab ground water samples up to 150 µg/1 (B-6) The general release of hydrocarbons and fuel additives emanated from the eastern edge of the northern dispenser island,and the product pipingjoining the two island northern most islands Once released into the subsurface,the shallow soil near the dispensers and a coarse grained,poorly to well sorted sand was impacted Once dissolved in the groundwater,the hydrocarbons only appear to have migrated to well MW-2 and MTBE has migrated laterally to well MW-3 and MW-2 Lower concentrations of MTBE have been detected in well MW-1, near the UST area Recent ground water analysis of well MW-4 has indicated an increasing, yet unpredictable trend of dissolved MTBE,while MTBE concentrations at well MW-3 have remained steady or declined The ground water at the location of monitoring well MW-5 has not been impacted by hydrocarbons and fuel additives The domestic well on the site has not been impacted by hydrocarbons and fuel additives The vertical extent of impacted ground water(hydrocarbons and fuel additives)appears to be limited the upper 35 feet of the water bearing strata on the site GfrT" �Vm • Advanced GeoEnWron mental,Inc