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Mr.Mike Oliphant—CEMC Soil and Groundwater Investigation Report March 29,2013 Ahern Road—Vernalis Page 4 of 6 RESULTS OF ANALYSES BTEX were not detected in any soil samples. Concentrations of TPHc above screening levels were detected in soil samples collected from borings SB-1 through SB-3, but not in borings SB-4 through SB-9. The PAHs benzo(a)anthracene, benzo(a)pyrene, 1-methylnaphthalene, and naphthalene were also detected above screening levels in borings SB-1 through SB-3. Naphthalene was the only compound detected above screening levels in soil samples collected from borings SB-4, SB-5, and SB-9. PAHs were not detected above screening levels in borings SB-6 through SB-8. Analytical results from analysis of soil samples are summarized in Tables 1 and 2. Due to the presence of SPO, groundwater samples were not collected from SB-1 and SB-3. The depth-discrete groundwater sample collected from SB-2 at 84 feet bgs contained concentrations of TPHd at 250 micrograms per liter(gg/L), which slightly exceeds the screening level. BTEX were not detected in the water sample collected from SB-2. Benzo(a)pyrene and dibenz(a,h)anthracene were the only two PAH detections that exceeded screening levels in the water sample collected from SB-2. With the exception of SB-4, BTEX compounds were not detected in the groundwater samples. Ethylbenzene and xylenes were detected in the grab groundwater sample collected from SB-4; the xylenes result(28 µg/L)exceeded the most conservative screening level (20 µg/L). The water sample collected from SB-6 contained 660 gg/L of TPHd. TPHd concentrations were also detected in SB-5, but did not exceed the screening level. TPHd concentrations were not detected in SB-4 and SB-7 through SB-9. The PAHs anthracene and benzo(a)pyrene were reported above screening levels in SB-5. PAH were not detected above screening levels in SB-4 or SB-6 through SB-9. None of the water samples from the most down-gradient borings (SB-7, SB-8, and SB-9) exceeded any screening levels. A general minerals analysis was also performed on the water sample collected from SB-4. Several parameters were detected in excess of RWQCB WQOs, and therefore groundwater beneath the site is not a suitable source for consumption based on its inherent qualities. Analytical results from analysis of groundwater samples are summarized in Tables 3, 4, and 5. A map showing the concentrations of the constituents in soil and groundwater and the extent of affected soil and groundwater is provided on Figure 3. A data usability discussion and the laboratory analytical report are included as Attachment D. The data usability evaluation determined that all analytical data are usable. SAIC also submitted a soil sample to Chevron Energy Technology Company (ETC) for fuel-fingerprint analysis. The soil sample was collected from boring SB-1 at 39 feet bgs. ETC concluded that, "The soil sample contains moderately weathered crude oil. The normal alkanes have been lost due to biodegradation with the iso-paraffins as the prominent peaks. The sample shows an UCM(unresolved complex mixture)hump stretching from C20-C44 hydrocarbon range. It has a very similar biomarker region ranged from C28-C32 compared with SJV crude oil." Fuel-fingerprint results are summarized in Table 6, and the ETC reports are provided as Attachment E.