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IThree limited excavations in the north east edge of the former dispensers removed an estimated 150 cubic yards of significantly petroleum-impacted soil The total depth of the three excavations was eight feet bsg The sidewalls and floor of excavations EXE2 and EXE3 exposed hydrocarbon- impacted soil Hydrocarbon-stained soil was not apparent in the final sidewalls and floor of 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 (EXE1) 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 m as 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 Img/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 wa de ctl B-1,B-6, B-7 and B-8 and MTBE was only detected in grab ground water samples fromS- 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 piping joining 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 ground water,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 cPT_ z(Y 1101 - 4u"—C Advanced Geolinviron mental,Inc 1