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CSK Auto#4025 GeoTek Project No.:BC122-4025 Tracy,California 95376 Page Iof 5 March 7,2000 2.0 ASSESSMENT ACTIVITIES Field investigation and sampling activities were conducted on February 17, 2000, under the supervision of GeoTek. Prior to the commencement of assessment activities, a utility locating service was contacted to locate utilities on or adjacent to the areas identified for soil borings. Drilling of the soil boring was performed by using a direct push (Geoprobe) method. The Geoprobe advances a 2.0-inch outside diameter, hollow-core stainless steel macro- sampler into the subsurface soils. Soil samples were extracted at continuous 4-foot intervals within a 4-foot long, 1-3/4 inch diameter acetate liner. The soil sample interval submitted for laboratory analysis was prepared by separating the acetate liner at the appropriate interval, covering the ends of the liner with Teflon sheeting, and then sealing each end with air tight caps. Each sample container was labeled with the soil boring number, depth of sample, site identification, date and time of sample collection, and initials of person collecting the sample. The samples were placed in a refrigerated ice chest containing dry ice or crushed ice. The samples were then shipped on ice by overnight courier service under chain of custody to the laboratory. All soil sampling equipment was cleaned with a laboratory grade detergent and triple rinsed with de-ionized water to prevent cross contamination of the samples. Upon completion of the soil borings, soil cuttings and/or grout was used to abandon the soil boring holes. Locations of the soil borings are shown on Figure 1, with pertinent field information summarized in Table 1. Pursuant to our scope of work, three soil borings 4025/SB-1/9'-10', 4025/SB-2/4'-5' and 4025/SB-3/4'-5' were advanced to an approximate depth of between five and ten feet below ground surface (bgs) at the locations corresponding to Figure 1. Soil samples from each boring were generally collected at various intervals using a stainless steel sampler and screened in the field for volatile organic vapors using a calibrated Photoionization Detector (PID). One soil sample from each of the three soil borings was submitted to the laboratory for Total Petroleum Hydrocarbon (TPH) analysis by EPA Method 8015 Mod. The soil samples exhibiting the highest PID response from each boring location were selected for laboratory analysis. In locations where soil samples exhibited no PID response, samples were submitted for laboratory analysis from the greatest depth sampled. Soil samples were submitted to Del Mar Analytical in Irvine, California (ELAP Certificate #1197) under chain of custody by overnight carrier for analysis. A complete copy of the laboratory analytical report is attached, and a summary of the analytes detected in soil is provided in Table 1.