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the presence of volatile organic compounds. The samples collected at three feet bgs from each of the four borings and one 16 to 1 laboratory composited sample consisting of the remaining soil samples (those collected every 5 feet) in each boring, were placed in a cooler with ice and submitted for laboratory analysis. Following soil sample collection, the borings were backfilled with cement grout to the surface. All drill cuttings, if any, were stored on-site in a 5-gallon container pending laboratory results. Copies of field notes are included in Attachment 1. Soil Sample Analysis The selected soil samples were transported, using chain-of-custody record, to State-certified NEI/GTEL Environmental Laboratories, Inc. for analysis. Samples from the four borings, five samples total, were analyzed for: priority pollutant metals (Sb, As, Be, Cd, Cr, Cu, Pb, Hg, Ni, Se, Ag, Tl, and Zn) by EPA 6010A; fuel fingerprinting (hydrocarbon screen) by EPA 8015M; benzene, toluene, ethylbenzene, and xylenes (BTEX), total petroleum hydrocarbons as gasoline (TPHg) by EPA methods 602/8020/8015; and organochlorine pesticides and PCB's by EPA method 8080. Copies of laboratory reports with chain of custody documentation are included in Attachment 2. Results Site boring logs and sediments encountered while drilling indicate that the site is underlain by generally two soil types, clay to approximately 3 to 5 feet bgs, and silt to 20 feet bgs. No petroleum hydrocarbons, BTEX, pesticides, or PCBs were detected in the soil samples analyzed. However, chromium, copper nickel, and zinc were detected above their corresponding laboratory detection limits in all the soil samples analyzed. The analytical results for these four metals were compared with the typical U.S. Mean and typical Bay Area concentrations in soil as presented in Summary of Typical Metals Concentrations in Soils and Surficial Materials, from U.S.G.S Professional Paper 1270 for the Conterminous United States (Attachment 3). In comparison, the metals detected appear to be at background concentrations. Conclusions No petroleum hydrocarbons, BTEX, pesticides, or PCB's were detected in the shallow soil samples or in the composite sample analyzed. Metals concentrations detected appear to be within natural background concentrations. No further investigation of the soil on-site appears to be warranted. The drill cuttings will be spread on-site pending PHS/EHD approval. All work described in this report was performed under the direct supervision of a California Registered Professional Engineer. wA97715VeportsVury4doe 2 SMTH