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detector (PID: Thermo Environmental Instruments, Inc. 580A,`Tt -O e.V., calibrated to isobutylene) was used to monitor organic vapors during excavation procedures. Samples collected during the UST removal (Table 1) indicated that impacted soil was present only near the north end of the excavation. Therefore, excavation was concentrated only in this area. The UST excavation was deepened from a depth of approximately 16 feet to a depth of approximately 31 feet. The length and width of the excavation were not expanded significantly (see Figure 2). No groundwater was encountered during excavation. Soil was also removed from two areas near the original dispensers, immediately north and northeast of the former USTs. Near the former west dispenser island, soil was excavated to a depth of 9 feet. Near the former east dispenser island, soil was excavated to a depth of 8.5 feet. Excavated soil was stockpiled at the south end of the site; soil excavated during the UST removal was also moved to this area. Approximately 75 cubic yards of soil were removed from the excavation on Februaiy 6, 1995. 3.2 Soil Sample Collection and Analysis One soil sample was collected from the floor of the UST excavation; two soil samples were collected from the dispenser/piping areas. All samples were collected from the excavator bucket using a metric soil sampler. Soil samples were collected under the supervision of Mr. Ron Rowe of the San Joaquin County Public Health Services - Environmental Health Division (PHS/EHD). Samples \\,ere collected in clean, 2 by 3-inch brass sleeves. The ends of the sleeves were covered with aluminum sheets, capped and sealed with tape. The samples were stored on ice and transported under chain-of-custody to McCampbell Analytical Inc. (MAI) in Pacheco. No soil samples were collected from the excavated soil. At the direction of the PHS/EHD, the samples were analyzed for total petroleum hydrocarbons (TPH as gasoline) and BTE&X in accordance with EPA methods 8015ni and 8020, respectively. 4.0 FINDINGS TPH as gasoline was detected in sample NB-1, collected from the floor of the UST excavation, at 240 mg/kg (parts per million, ppm). Benzene, toluene, ethylbenzene and xylenes were also detected in sample NB-1 at concentrations of 0.12 ppm. 3.0 ppm, 1,5 ppm and 21 ppm, respectively. No petroleum hydrocarbons were detected in the samples from the dispenser areas. Analytical results are summarized on Table 2. The laboratory report and chain-of-custody are included in Appendix A. OW10 iui A,&Se mimes,Inc. [ SG95-0l-1076-0ZCOUNTRY MART/u rq J v