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each at 3 feet). The data indicate that leakage has occurred from Tank #2 and Dispenser#2 into soil. A water sample collected from the tank pit was also contaminated. Six exploratory borings were drilled in and around the former underground storage tank pit in February 2003. The borings revealed TPHG, TPHD, MTBE and Bunker Oil in borings adjacent to the former tank pit and north of the building. Separate phase product was observed in Barings B-3, B-4 and B-5. Residual contaminants with low in BTEX are interpreted present in the tank pit vicinity. MTBE and low levels of TAME and TBA were present at B-1, B-2 and B-3. Since data was collected from uncased boreholes in which groundwater had not stabilized, a plot of groundwater was not prepared. The contaminant distribution indicates tank leakage has reached groundwater and moved in a roughly northerly direction. The northerly and easterly extent of the dissolved plume was not mapped during this assessment. Scope of Work 2.0 2000-foot Radius Well Survey and Sensitive Receptor Survey Wright will perform a 2000-foot radius search for wells around the Boyd Service Center site. The search will use the available information from the Department of Water Resources files and City of Tracy and County files to document municipal, domestic, agricultural, industrial and other wells. The information will be compiled into a summary table together with a map showing the well locations. Additional information will include a brief review of potential sensitive receptors in the area. 3.0 Field Methods—Drilling and Sampling Exploratory Borings Exploratory borings will be drilled at the locations shown on Figure 1. Drilling permits will be secured from SJC/EHD, and the above referenced underground utility clearance will be performed prior to doing the fieldwork. The soil borings are to be advanced to a depth of about 20 to 25 feet but not below the aquitard and are located to further define the dissolved plume northerly and easterly extent. The boreholes will be drilled with truck mounted GeoProbe direct-push drilling equipment. All drilling equipment and sampling tools will be cleaned prior to arriving, between each sampling borehole and before leaving the site. The probe will collect continuous cores of soil in each borehole. The sampler will then be retrieved and dissembled and soil sample intervals retained for chemical analysis will be cut from the liners at the desired depths. Each soil sample will be sealed with Teflon paper or foil and plastic endcaps, labeled, logged onto chain-of-custody forms and place in a chilled ice chest on crushed ice for transport to the laboratory. The boreholes will be continuously logged using the Unified Soil Classification System under the supervision of a professional geologist. Additional lithologic information will be collected as Page 2 of 6