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i f � C 2.0 EXCAVATIONAND STOCKPILING The four areas containing TPH concentrations greater than the SJC action level of 100 mg/kg included the perimeter ditch behind the wash area (Area 1 ), underneath the machine room waste bins (Area 4), outside the west doors of the repair shop (Area 8), and the west side of the equipment storage area (Area 2). Areas 3, 5, 6, and 7 had significant surface staining, but had concentrations of TPH lower than the SJC action level. These areas are shown in Figure 2. Approximate dimensions of each excavation were estimated prior to the start of field work, using analytical results from the Phase II investigation. The dimensions of the actual excavation were measured in the field by the field geologist. The final measured dimensions are shown on Figure 2. IC The soils were removed from the excavations with a backhoe. Excavation continued Cuntil all visibly stained soil was removed. The soils removed from each excavation iwere stockpiled on and covered with plastic sheeting (Figure 2). The stockpile of soils from all areas except Area 1 contained approximately 31 cubic yards of soil. t� The soil removed from the ditch behind the wash area (Area 1 ) was placed on and covered with plastic sheeting in a separate stockpile. The results from the Phase II Site Assessment indicated that this area contained elevated levels of lead and cadmium, which could require that the excavated material be disposed of at a licensed CClass I landfill. The ditch stockpile contained approximately 40 cubic yards of soil. C2. 1 Storm Drain During excavation of the of the ditch behind the wash area, the end of a drain pipe Cfrom the on-site storm water collection system was uncovered. This 1 2-inch diameter steel pipe was connected to a 8-inch steel pipe running down the middle of the ditch. CCIMAIN\FMC\5042\FMCRM.DOC 2_1 99IHYORO-SERRCHAI G A Tetra Tech Company I - -