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i a Monitoring Well Installation Report-Tosco(Former BP)Service Station No 11192 SepleMber 26.2001 California (FLAP #1271) The soil and groundwater samples were analyzed for TPHg by Environmental Protection Agency (EPA) Methods 8015 Modified, BTEX and MtBE by EPA Method 8020, Ethanol, tert-Butyl alcohol (TBA), MtBE, Di-isopropyl ether (DIPE), ethyl tert-butyl ether (ETBE), 1,2-Dichloroethane (1,2-DCA), tert-Amyl methyl ether (TAME) and Ethylene dibromide (EDB) by EPA Method 8260 In addition, the groundwater samples were analyzed for Methanol by EPA Method 8015 modified Also, the stockpile sample was analyzed for total lead by EPA Method 6010 Copies of the laboratory analytical reports and chain-of-custody records are included in Appendix E 4.3 Soil Analytical Results Soil samples collected from wells MW-8, MW-9 and MW-10 did not contain detectable concentrations of any of the hydrocarbon constituents analyzed Soil sample MW-11-14, collected at 14 feet bgs, contained 17 ppm of MtBE The stockpile sample, Comp-1(A-D), contained MtBE at 0 22 ppm and lead at 7 ppm These results were acceptable for landfill disposal Soil chemical analytical data are summarized in Table 3 4.4 Groundwater Analytical Results The groundwater samples collected from MW-8, MW-9 and MW-10, did not contain detectable concentrations of any hydrocarbon constituent anaylzed TPHb and BTEX were not detected in the groundwater sample from MW-1 However, MtBE was detected in MW-11 at 170 ppb (EPA Method 8020) and 110 ppb (EPA Method 8260) Groundwater chemical analytical data for the four new wells are summarized in Table 1 4.5 Waste Disposal All waste water generated by cleaning the drilling equipment and well development and sampling procedures was removed from the site and transported to the Tosco Refinery in Rodeo, California, for disposal Drill cuttings were placed on and covered with plastic sheeting and stored onsite pending disposal One two part composite sample [Comp-1(A-D)] was collected from the stockpile and submitted to the laboratory for analysis and disposal characterization The analytical results from the composite soil sample were submitted to Allied Waste's Forward landfill in Manteca Allied Waste has A copy of the Forward Iandfill acceptance letter is included in Appendix F 5.0 CONCLUSIONS AND RECOMMENDATIONS r Analytical results of the groundwater samples from offsite wells MW-8, MW-9, and MW-10 show no detectable concentrations of dissolved hydrocarbon, indicating the lateral extent of the plume in the shallow water table is well defined Analytical results of the initial sample from deep monitoring well MW-11 indicated 110 ppb of MtBE It is GR's experience that initial sample 14024505-2 7