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., Chevron Products Company 2 Chevron Station#9-2396 25650 Highway 99 North Acam o California JuIv 12 2001 three new 12,000-gallon USTs. Analytical results for soil samples reported low levels ✓ (1.9 ppm to 410 ppm) of total petroleum hydrocarbons calculated as gasoline (TPHg), benzene (0.008 ppm to 0.11 ppm), toluene (0.009 ppm to 6.7 ppm), cthylbenzene (0.008 ppm to 69 ppm), and xylenes (0.009 ppm to 46 ppm). On June 24 and July 28, 1994, water samples were collected from the domestic water supply well located near the frontage road, west of the pump islands. Analytical results reported non-detectable levels of TPHg, and benzene, toluene, ethylbenzene, and xylenes (BTEX) on both occasions. ASSESSMENT ACTIVITIES AND FINDINGS On April 26 and 27, 2001, SECOR supervised Cascade Drilling of Rancho Cordova, California in drilling three soil borings to approximately 79 feet below ground surface (bgs). The soil borings (SB) were drilled using hollow stem augers. The exploratory borings were advanced at the general locations shown in Figure 2; one boring (SB-1) was located in the area adjacent to the gasoline USTs, one boring (SB-2) was located between the fuel facilities and the on-site domestic well, and one boring (SB-3) was located in the area of the former waste oil UST. Soil samples were collected every five feet for logging and field screening. The 65-foot interval and 75-foot interval soil samples from each boring were submitted for analysis. A groundwater sample was also collected from each borehole and submitted for analysis. A groundwater sample was also collected from the on-site domestic water well. Field and laboratory procedures are presented as Attachment A. The findings of this assessment are summarized below: • Lithology. Primarily sands and silt-sand mixtures were encountered from below the asphalt surface to the total depth of the borings. Soil boring logs are included as Attachment B. • Soil Analytical Results. Select soil samples were submitted to a California state-certified laboratory and analyzed for the presence of: purgeable hydrocarbons (i.e.TPHg), BTEX, fuel oxygenates, and total lead. Fuel oxygenates include tert-butyl alcohol (TBA), methyl tert- butyl ether(MtBE), di-isopropyl ether (DIPE), ethyl tert-butyl ether (EtBE), tert-amyl methyl ether(TAME), ethanol, 1-2 dichloroethane (1-2 DCA) and ethylene dibromide (EDB). TPHg and BTEX were analyzed using the DHS/LUFT method, fuel oxygenates were analyzed using EPA Method 8260A, and lead analysis was performed using EPA 6000/7000 series. The laboratory did not detect these constituents in soil samples. Certified analytical reports and chain-of-custody record are presented in Attachment C_ I:1ChevronW23961Reports1.1u1y 2001 Site Assessment Report.doc