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of the diesel tank overburden stockpile sample STP-EMR-002, revealed 11 ppm gasoline, 0.038 ppm toluene, 0.457 ppm ethyl benzene and 0.41 ppm total xylenes. Both stockpile samples were found to contain total lead concentrations equivalent to natural background levels, and were found to be non-reactive, non-corrosive and not ignitable. Analysis of the overexcavation verification soil samples SSA-EMR-006, SSA-EMR-007 and SSA-EMR-008 (collected from the gasoline tank excavation floor and southern sidewall following overexcavation), revealed no detectable petroleum hydrocarbon concentrations. _ Analysis of the overexcavation stockpile sample STP-EMR-003, revealed 260 ppm gasoline, 0.49 ppm benzene, 1.9 ppm toluene, 2.8 ppm ethyl benzene, 20 ppm xylenes and 0.31 ppm MTBE. A total lead concentration equivalent to the natural background level was encountered in the STP-EMR-03 sample upon analysis. The sample was determined to be non-reactive, non-corrosive nd not ignitable upon analysis. All soil sample analytical results are listed in Table 1 with laboratory reports included in Appendix F. 2.5 New Tank Installation and Excavation Backfill After gasoline tank overexcavation verification soil sample analyses were complete, the analytical data was submitted to Harlan Knoll of the SJCPHS-EHD for review and authorization to install the new 15,000 gallon split tank in the gasoline UST excavation, and backfill above the new tank with clean fill material. Authorization was also given to reinstall the gasoline tank overburden stockpile in the diesel tank excavation, as no detectable petroleum hydrocarbon concentrations had been encountered in the composite sample collected from that stockpile. Reinstallation and backfill approval was received on May 3, 1996, with field operations beginning on May 6, 1996. The new tank was emplaced and clean pea gravel and base rock were then introduced to the hole by Aronson representatives, in the quantities necessary to return the level to grade. As pea gravel achieves 90% compaction by nature, no mechanical compaction was required at the site. Following completion of all backfilling activities, resurfacing was then completed at the site by representatives of Aronson Engineering. 2.6 Soil Disposal During UST removal and gasoline tank overexcavation activities, two overburden and one overexcavation soil stockpiles (approximately 430 yd' of soil) were generated. The gasoline 5