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' 18 July 2002 . AGE-NC Project No 96-0254 ' Page 3 of 17 2 4 UST REMOVAL ' AGE was informed that three USTs, dispensers and piping i were removed from the site on 31 July P 1991, and that the removal was witnessed by a representative of the EHD, additional information regarding history of the UST use, tank tests, product inventory and repairs are not known to AGE Six soil samples were collected from the sidewalls during the 31 July 1991 excavation, at a depth of five feet below surface grade (bsg), no excavation floor samples were collected because groundwater was encountered in the excavation at a depth of approximately six feet In addition,one ' grab groundwater sample was collected from the excavation and one soil sample was collected beneath the piping/dispenser area The soil and ground water samples were analyzed for TPH-g, BTEX, Iead and ethylene dibromide (EDB) IConcentrations of TPH-g and BTEX compounds were detected in each soil sample collected from the UST excavation TPH-g was detected from the east wall of the UST excavation at a maximum concentration of 62 milligrams per kilogram(mg/kg)and from the west wall of the UST excavation at a maximum concentration of 26 mg/kg Benzene was not detected above the elevated detection limits in the soil samples collected from the UST excavation walls Lead was detected at a maximum . concentration of 10 mg/kg EDB was detected in one sample at a concentration of 2 9 mg/kg TPH-g and BTEX compounds were detected in the water sample at concentrations of 150,000 micrograms per liter (gg/l) and 25,000 gg/l, 43,000 µg/l, 5,700 µg/1 and 32,000 µg/l, respectively Lead was detected at a concentration of 0 67 µg/1 in the water sample,however, EDB was not detected I3.0. ASSESSMENT OF HYDROCARBON-IMPACTED SOIL AND GROUND WATER On 24 June 1997, a total of nine soil probe borings(B 1 through B9)were advanced at the site under ' EHD oversight Probe borings were advanced in the area of the farmer USTs,and northward towards the property line(Figure 2) Soil in probe borings BI through B5 were continuously sampled(cored), whereas soil in probe boring B6 was sampled at the vadose zone/ground water interface In addition, I grab ground water samples were collected from B 1 through 139 The grab ground water samples and selected soil samples were analyzed for TPH-g,TPH-d,BTEX and methyl tert-butyl ether(MTBE), however, soil samples collected from probe boring B1 were not analyzed, because field screening with a organic vapor monitor (OVM) indicated that the samples were not impacted by petroleum hydrocarbons • TPH-g was detected in six soil samples collected from four of the probe borings,B2,B3,B4 and B5 TPH-g was detected at concentrations as high as 5,000 mg/kg (B5-6') at depths of 8 feet bsg or less TPH-g concentrations detected in soil from depths greater than 8 feet bsg Iadvanced GeoEnvsronmental,Inc I