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3.10 Groundwater Sample Collection Water samples were collected from each well using a new disposable plastic bailer. Each water sample was collected in two 40 ml VOA vials. A one-liter amber bottle of water was .J also collected from MW-1. Samples were transported in a chilled container to MAI and analyzed for TPH as gasoline and BTE&X in accordance with EPA methods 5030 and 602, respectively. 3.11 Monitoring Well Surveying On November 4, 1994, the casing elevations of MW-1, MW-2 and MW-3 were surveyed relative to the top of a crash pole located at the northeast corner of the store. The pole was J assigned an arbitrary elevation of 100.00 feet. 3.12 Groundwater Monitoring - December 1994 On December 5, 1994, the depth to groundwater was measured in the three wells on-site. Each well was then purged and samples collected and analyzed following the procedures described in Sections 3.9 and 3.10. 4.0 FINDINGS 4.1 Analytical Results of Excavation Samples •1 No contamination was detected in any of the soil samples collected during the excavation. Petroleum hydrocarbons were detected in the water sample collected from the excavation. Table 2 summarizes the laboratory results. The laboratory report and chain-of-custody are included in Appendix A. 4.2 Analytical Results of Stockpile Samples TPH as gasoline was detected in initial samples collected from SP-1, SP-2 and SP-3 at concentrations of 1,100 ppm 3.8 ppm and 390 ppm respectively. Toluene, ethylbenzene and xylenes were also detected in stockpiles SP-1 and SP-3. No benzene was detected in any of the stockpile samples. Concentrations of petroleum hydrocarbons decreased over time after inoculation with the bacterial medium. No petroleum hydrocarbons were detected in stockpiles SP-3 and SP-4 during the first and second confirmatory samplings, and this soil was subsequently returned to the excavation. 0 1&.1 A.&s.M w 1� 10 CA D1lOM...~-9S