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08 November 2005 i AGE-NC Project No. 98-0481 ' Page 2 of 8 2.2. UNDERGROUND STORAGE TANK REMOVAL In July 1997,Walton Environmental,Inc. excavated and removed three fuel USTs, a waste oil UST, a fuel dispenser island and associated product piping. As part of the removal activities, Grayland ' Environmental collected a total of I I soil samples for laboratory analysis beneath the USTs, dispensers, and associated product piping. Soil sample locations are illustrated on Figure 2. Soil samples were collected at approximately 12 to 14 feet below surface grade (bsg) from the base of the fuel UST excavation; approximately 4 feet bsg beneath the fuel dispensers and product piping; and approximately 8 feet bsg from the waste oil UST excavation. Soil samples were analyzed for benzene, toluene, ethylbenzene, total xylenes (BTEX), total petroleum hydrocabons as diesel (TPH-d) and gasoline (TPH-g), methyl tertiary-butyl ether (MTBE), and total lead. ' There were no detections of BTEX, TPH-d, TPH-g, MTBE or total lead in the six soil samples collected beneath the three fuel USTs or product piping located between the tank excavation and the fuel dispenser island. However, BTEX, TPH-d, TPH-g, and MTBE compounds were detected in three soil samples collected beneath the fuel dispenser island and product piping located along the southern side of the fuel dispenser island. The highest concentrations of target compounds were detected in soil samples collected beneath the fuel dispenser island;benzene at 0.14 milligrams per � . kilogram(mg/kg),toluene at 0.75 mg/kg, ethylbenzene at 0.021 mg/kg,total xylenes at 0.73 mg/kg, TPH-d at 140 mg/kg, and TPH-g at 1.9 mg/kg (Table 1). In addition, benzene, TPH-d, and MTBE were detected in the soil sample collected beneath the waste oil UST. Duringthe excavation of the USTs and product piping, excavated soil was stockpiled and allowed to aerate on an adjacent parcel located east of Emil's Liquors.A total of five composite soil samples were collected from the stockpiles for laboratory analysis. TPH-d was detected in one composite stockpile sample;and BTEX,MTBE,and TPH-g were detected in two composite stockpile samples. In addition,concentrations of total oil and grease,halogenated volatile organic compounds(HVOCs) and LUFT metals were detected in the soil sample collected from the waste oil UST soil stockpile. 2.3. PREVIOUS SITE INVESTIGATIONS In May 1993, WHF Environmental, Inc. conducted a Phase II Site Assessment to investigate subsurface soil for possible petroleum hydrocarbon contamination resulting from historical hydrocarbon fuel storage and distribution operations at the site. During the Phase II investigation, ' four soil borings (B-I through B-4) were advanced in the area surrounding the fuel USTs and the dispenser island; the approximate locations of the soil borings are illustrated on Figure 2. Soil samples were collected from each of the borings at depths of 15, 20, and 25 feet bsg for laboratory analysis. The laboratory reported no detections of BTEX, TPH-d or TPH-g for any of the soil samples analyzed (Table I). Advanced GeoEnvironmental,Inc..