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. 25 August 1998 AGE-NC Project No. 98-0481 Page 2 of 7 2.2. PREVIOUS INVESTIGATIONS AGE reviewed available reports for two previous environmental assessments conducted at the site. A brief summary of previous investigation findings is presented below. 2.2.1. Phase II Site Assessment In May 1993,WHF Environmental,Inc. conducted a Phase lI Site Assessment to evaluate subsurface soil for possible petroleum hydrocarbon contamination resulting from historical hydrocarbon fuel storage and distribution operations at the site. During the Phase 11 investigation, four soil borings (B-1 through B-4) were advanced in the vicinity of the three former fuel USTs and the former dispenser island. Approximate boring locations are illustrated on Figure 2) Soil samples were collected from each of the borings at depths of 15, 20, and 25 feet below surface grade (bsg) and submitted for laboratory analysis. No benzene,toluene, ethyl-benzene, total xylenes (BTEX), total petroleum hydrocarbons as diesel (TPH-d) or total petroleum hydrocarbons as gasoline (TPH-g) were detected in soil samples ianalyzed. Soil samples were not analyzed for fuel oxygenates or lead. During drilling activities, groundwater was not encountered in any of the borings. 2.2.2. Underground Storage Tank Removal In July 1997, Walton Environmental, Inc. excavated and removed the three fuel USTs, one waste oil UST, the fuel dispenser island and associated product piping. As part of the removal activities, Grayland Environmental collected a total of eleven soil samples for laboratory analysis beneath the USTs,pump island, and associated product piping. Approximate soil sample locations are illustrated on Figure 2. Soil samples were collected at approximately 12 to 14 feet bsg in the UST area; approximately 4 feet bsg in the fuel dispenser island and product piping areas; and approximately 8 feet bsg in the waste oil UST area. Soil samples were analyzed for BTEX, TPH-d, TPH-g, methyl tertiary-butyl ether (MTBE), and total lead. BTEX, TPH-d, TPH-g, MTBE or total lead were not detected 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. BTEX concentrations were detected as high as 0.14 pars per million (ppm), 0.75 ppm, 0.021 ppm and 0.73 ppm, respectively. Advanced GeoEnvironmental,Inc.