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(vATc A s s n C I A ? E S I N C 2.1 Drilling Activities On May 4, 2001, ATC supervised the advancement of two soil borings to 36 feet below -ound surface (bgs). A site plan with soil boring locations is shown on Figure 2. Fisch Environmental, California License C57 683865, advanced the borings using a truck mounted Geoprobe® narrow diameter rig employing direct push technology. Soil samples were collected from boring 3 SB 1 and SB2 at five-foot intervals in acetate sampling tubes and were described according o the Unified Soil Classification System. Descriptions of soil types encountered, field observations, and sample collection intervals are presented on the boring logs contained in Appendix A. 2.2 Soil Sampling and Analysis Each soil sample was field screened with a Flame Ionization Detector (FID) for the presence of volatile organic compounds. FID readings were never measured above the background level of 7 parts per million by volume. Sample tubes were then sealed at each end using Teflon tae and plastic end caps, labeled, and placed on ice. Selected soil samples were kept on ice and del vered under chain-of-custody documentation to State-certified Argon Laboratories Inc. (FLAP Cert. No. 2358) for chemical analysis. Following sample collection, the borings were grouted to the surface with neat cement. Two soil samples from each boring were analyzed for total petroleum,hydrocarbons as gasoline (TPHg) and total petroleum hydrocarbons as diesel (TPHd) by EPA Methods 8015, and for benzene, toluene, ethylbenzene, xylenes (BTEX) and methyl tertiary butyl ether (MTBE) by EPA Methods 8020. The samples were analyzed on a 24-hour turnaround time. 3.0 SUBSURFACE CONDITIONS Soil from borings SB 1 and S132 consisted of silty clay from the surface to depths between 16 and 19 feet bgs with a layer of sandy silt present in boring SB2. Soil in boring SBI contained silty sand from depths between 16 and 19 feet bgs to 21 and 24 feet bgs. Soil in boring SB 1 contained silty clay and sandy clay from depths between 21 and 24 feet bgs to 36 feet bgs, the maximum depth explored. Soil in boring SB2 contained sandy silt from depths between 16 and 19 feet bgs and 31 and.34 feet bgs with a layer of sand present. Soil in boring S132 contained silty cla from depths between 31 and 34 feet bgs and 36 feet bgs, the maximum depth explored. Soil I oring- logs with a detailed description of soil types are contained in Appendix A. 4.0 RESULTS None of the soil samples collected from borings SB 1 or S132 contained detectable concentr tions of TPHg, TPHd, BTEX, or MTBE. Analytical results of soil samples are summarized in TE ble 1. Laboratory data sheets and chain-of-custody documentation are presented in Appendix B. w190754\br55\55Wsum.doc 2 .