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3.0 SAMPLING METHODS 3. 1 Confirmatory Samples Confirmatory samples were taken from Area 1 and from excavations in areas with TPH concentrations greater than the SJC action level. If the excavation was less than three feet deep, confirmatory samples were taken only from the floor of the excavation. If the excavation was three feet deep or greater, confirmatory samples were also taken from excavation sidewalls. Confirmatory samples were not collected from areas with TPH concentrations below the SJC action levels. CTwo confirmatory samples were collected from each of the long sidewalls at a depth i of 2 feet below ground surface (bgs) (Figure 2)• Confirmatory samples were also taken in Area 4 from all four walls at 3 feet (bgs). Areas 2 and 8 were less than three Cfeet deep so only floor samples were taken. Soil was removed from Areas 3, 5, 6, and 7 to a depth of 0.5 foot because of surface staining and no confirmatory samples were taken. Confirmatory samples were taken using a soil core sampler fitted with a clean 2" x 6" brass tube. The core sampler was driven into the soil using a slide hammer attached to the core sampler. Both ends of the brass tubes were covered with Teflon° tape and a fitted plastic cap. The samples were labeled with the date, time, site name, sample number, sampler's initials, and the required analyses. The samples were stored in a chilled, insulated cooler and transported to Pace Analytical Laboratories in CPetaluma, California, within 24 hours for analysis. The confirmatory samples were analyzed for TPH using EPA method 8015, modified. ' 3.2 Stockpile Samples ! The stockpiles were also sampled using clean 2" x 6" brass tubes. The samples were i collected from below the surface of the stockpile using a clean stainless steel scoop : C (^ C:\MAIN\FMC\5042\FMCRM.DOC 3.1 i! i C WHYDRO-SEARCH, II IC. A Tetra Tech Company