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Stantec PHASE II ENVIRONMENTAL SITE ASSESSMENT REPORT Laboratory Analytical Results and Screening March 31,2011 3.2 SOIL SAMPLE ANALYTICAL RESULTS Soil samples were collected from each soil vapor borehole during the hand augering of the boreholes. Selected soil samples from SS-1, SS-5, and SS-6 were chosen for chemical analyses based on locations of suspected historical features/existing subsurface impact (Tables 2 through 4). The soil samples were analyzed for TPH fuel fingerprint (LUFT method), VOCs (USEPA method 8260), and CAM 17 metals by BC Labs. The remainder of the soil samples were placed on hold, pending the soil vapor analytical results. Based on the soil vapor analytical results, soil sample SS-2 was analyzed for VOCs due to the PCE concentration observed in the sample. The following analytical results were reported in the soil samples: Volatile Organic Compounds: The VOC results for the soil samples are reported in Table 2. As part of the soil vapor investigation 4 soil samples were analyzed for VOCs out of the 6 soil samples collected. The soil samples were analyzed for VOCs at 5 feet bgs and were reporting in milligrams per kilogram (mg/kg). VOCs were not detected above the laboratory Method Detection Limits (MDLs) for any of the VOC compounds, except for trace amounts of tetrachloroethene (0.0033 J mg/kg) in sample SS-1 and trace amounts of toluene (0.0034 J mg/kg), 1,2,4-trimethylbenzene (0.0024 J mg/kg), total xylenes (0.0062 J mg/kg), p- & m- xylenes (0.0045 J mg/kg), and o-xylenes (0.0017 J mg/kg) in sample SS-6. The 'J' flagging are estimated values that are reported between the Practical Quantitation Limit and the MDL. All of the detections were below the USEPA Regional Screening Levels (RSLs) for shallow industrial soil and the RWQCB ESLs for shallow soils (<3 meters bgs) where groundwater is a current or a potential source of drinking water. The MDL reporting limits were generally several orders of magnitude below the RSLs and ESLs. The VOC analyses for soil sample for SS-2 was performed due to the PCE concentrations reported in the soil vapor sample. PCE was not detected in the soil sample SS-2. TPH Fuel Fingerprint: The TPH fuel fingerprint results for the soil samples are reported in Table 3. As part of the soil vapor investigation 3 soil samples were analyzed for TPH fuel fingerprint out of the 6 soil samples collected. The TPH fuel fingerprint results were not detected above the laboratory MDLs, except for detections of 55 and 31 mg/kg of TPH-hydraulic oil/motor oil in soil samples SS-5 and SS-6, respectively, and 87 mg/kg of TPH-diesel in soil sample SS-6. The laboratory chromatograms for soil sample SS-6 were not typical for TPH-hydraulic oil/motor oil and TPH-diesel, and appear to be more representative of a weathered hydrocarbon, due to very low volatile fraction. Although the TPH detections were slightly above the TPH-diesel ESLs for shallow soils (<3 meters bgs) where groundwater is a current or a potential source of drinking water, the lack of volatile hydrocarbon constituents in this weathered hydrocarbon is considered to lower the significance of this finding. The MDL reporting limits were at least one order of magnitude or more below the USEPA RSLs for shallow industrial soil and the RWQCB ESLs for shallow soils (<3 meters bgs) where groundwater is a current or a potential source of drinking water. is\projects\calpine\lodi\report\lodi.svrpt.do" 3.2