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Monitoring wells, located approximately 1/2 mile north of the subject site, installed and maintained by GeoAudit, indicated a depth to groundwater of approximately 64 feet in February of 1994. 3.0 PROCEDURES 3.1 Excavation Procedures On June 6, 1994, the existing tank cavity was overexcavated to remove residual soil contamination. The excavator and operator were supplied by Bob Evans Trucking of Manteca,California.A photo-ionization detector(PID:Thermo Environmental Instruments, Inc. 580A, 10.0 e.V., calibrated to isobutylene) was used to monitor organic vapors during excavation procedures. The excavation was expanded approximately 2 feet to the south and west; excavation in the south and west directions was limited due to the property line (see Figure 2).The excavation was extended to a depth of approximately 15 feet. No groundwater was encountered during excavation. The excavated soil was stockpiled east of the excavation and existing stockpile. Approximately 100 cubic yards of soil were removed from the excavation. 3.2 Soil Sample Collection and Analysis Upon termination of excavation, three samples were collected from the floor, the west wall and the south wall of the excavation (B1-15, W1-9 and S1-11). Samples from the excavation were collected from the excavator bucket using a metric soil sampler. Two samples were also collected from the stockpiled soil. Sample locations are shown on Figure 2. Samples were 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 to McCampbell Analytical Inc. in Pacheco. The two stockpile samples were composited at the laboratory for analysis. The samples were analyzed for total petroleum hydrocarbons (TPH as gasoline and diesel) and BTE&X in accordance with EPA methods 8015m and 8020, respectively. 4.0 FINDINGS TPH as gasoline was detected in sample S1-11 (south wall of excavation, 11 feet) at a concentration of 1.1 mg/kg (parts per million, ppm).Xylenes were detected in the composite stockpile sample at 0.029 ppm. No other petroleum hydrocarbons were detected in any of the samples. Analytical results are summarized on Table 1. The laboratory report and chain of custody are included in Appendix A. 0.68.1 A.Q S.M..,I- 4�.... s