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Working To Restore Nature Following excavation, confirmation samples were collected under the direction of Ms. Turkatte. Soil sample locations are depicted on Plate 3. Four sidewall samples and one floor sample were collected from the excavator bucket at least three inches below the surface of the soil The samples were collected into prewashed brass liners, sealed with Teflon sheets and plastic end caps, placed in air-tight bags and preserved on ice pending shipment to Sequoia Analytical (DHS Cert #1210) in Redwood City, California. Sample location and lithologic descriptions are included in Attachment i Soil samples were transported under chain-of-custody protocol to the laboratory for analysis of benzene, toluene, ethylbenzene, and xylenes (BTEX) and total petroleum hydrocarbons as diesel (TPHd) using EPA methods 8020 and modified 8015, respectively Former Waste Oil Tank Location Approximately 15 cubic yards of soil were removed prior to sampling in the former waste oil tank location No olfactory or visual evidence of residual contamination was noted during over- excavation At Ms Turkatte's request, the pit was backfilled with the excavated soil Prior to backfilling, a floor sample was collected from approximately 9 5 feet below grade from the excavator bucket as described above The sample was submitted for analysis of BTEX utilizing EPA method 8020, TPHd and TPHg utilizing EPA method 8015, total oil and grease utilizing SM5520 E/F, halogenated volatile organics (HVOs) utilizing EPA method 8010, polychlonnated biphenyls (PCBs) utilizing EPA method 8080, and cadmium, chromium, lead, zinc, and nickel Analytical results are summarized in Table 1 Stockpiled Soil Petroleum hydrocarbon impacted soil was underlain and covered with 6-mil plastic sheeting One 4-sleeve composite sample was collected from the stockpiled soil and analyzed for BTEX and TPHd by the methods described above as well as for HVOs, total threshold limit concentration (TTLC) metals, and corrosivity, ignitability, and reactivity The excavated soil was transported to Forward Landfill in Manteca, California for disposal Copies of the non- hazardous waste manifests are included in Attachment 2 ANALYTICAL RESULTS Former Diesel Tank Location Laboratory analysis determined that no BTEX constituents were present in any of the confirmation samples collected from the former diesel tank pit TPHd (20,000 ppm) was reported in the sample from the north wall of the pit where excavation was limited by public easements Low levels of TPHd were also reported in the samples from the floor (2 8 ppm), the east wall (5.2 ppm), and the south wall (1.9 ppm). TPHd was not detected in the sample from the west wall of the pit >;xcnv FNL 3