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Mr. Michael Infurna June 14, 1999 Page 2 No groundwater was encountered during the tank removal. Based upon data from the San Joaquin County Flood Control and Conservation District, groundwater beneath the site is expected to occur at approximately 40 to 50 feet below ground surface (bgs) and flow generally southeast. SCOPE OF WORK Ground Zero will supervise the drilling and sampling of two soil borings in the vicinity of the former fuel dispenser. One boring will be placed in the center of the former dispenser, and one boring will be placed approximately 15-25 feet southeast of the former dispenser in an attempt to determine the lateral extent of soil contamination in the assumed downgradient direction. Proposed soil boring locations are shown on Figure 2. The borings will be advanced to a depth of approximately 20 feet bgs or until the vertical extent of soil contamination has been determined, based on field observations. A drilling company licensed in the State of California will advance the borings using a truck mounted Geoprobe 5400 direct push rig. Soil samples will be collected for logging and identification purposes at 5-foot depth intervals. Samples will be collected using a 1-inch diameter, 24-inch long core sampler lined with clear acetate sleeves. The portion of the sample to be analyzed will be immediately capped and preserved in an iced cooler at a temperature of approximately 4° Centigrade. No cuttings requiring disposal will be produced using the direct push drilling method. Borings will be backfilled to the ground surface with neat cement grout. Up to four soil samples (two from each boring) will be submitted for analysis of total petroleum hydrocarbons as diesel (TPHd) using EPA method 8015 modified; and benzene, toluene, ethylbenzene, xylenes (BTEX) using EPA method 8020. Selection of soil samples for laboratory analysis will be based on field evidence of petroleum hydrocarbon contamination such as discoloration, odors, and FID readings, as well as lithologic changes. All sampling and drilling equipment will be washed thoroughly with laboratory-grade detergent and water between uses to minimize the potential for cross contamination. All fieldwork will be conducted in accordance with the Site Safety Plan included in Attachment A. A technical report describing field activities, analytical results, conclusions and recommendations will be submitted to Mr. Arnie Taylor, PHS/EHD, and the California Regional Water Quality Control Board (CRWQCB). A completed drilling permit application and associated fees will be submitted under separate cover upon your approval of this workplan. taylor\reports\wp0699.doc