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F " ~ 77 Ms. Margaret Lagorio February 28, 2003 Page 2 of 3 SCOPE OF WORK Ground Zero will supervise the drilling and sampling of a single soil boring at the south end of the former UST, near where residual gasoline constituents were detected. Figure 2 presents the proposed location of the soil boring. The boring will be advanced to a depth of approximately 25-30 feet bgs, until the vertical extent of soil contamination has been determined, or to first groundwater, as appropriate 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 drilling rig. Soil samples will be collected for logging and identification purposes at 5-foot depth intervals. Samples will be collected using a 1.5-inch diameter 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. We anticipate collecting three soil samples and one groundwater sample from the boring for chemical analyses. Soil samples from approximately 15 feet bgs, 20 feet bgs, and 25 feet bgs will be submitted for analysis of volatile organic constituents (VOCs), including benzene, toluene, ethylbenzene, xylenes (BTEX), MTBE, TBA, and other oxygenated gasoline additives using EPA method 8260B. One discrete groundwater sample will also be collected from the boring and analyzed for the constituents listed above. The sample will be collected by driving the sampler to the desired depth and exposing the screen to the formation. The groundwater sample will be collected using a length of polytetrafloroethylene (PTFE) tubing equipped with a stainless steel bottom check valve. The tubing will be inserted into the probe rods and pushed to the bottom of the sampler at the desired depth. The groundwater sample will be brought to the surface by gripping the top of the tubing and rapidly moving the tubing up and down creating a positive displacement effect, thereby forcing the water sample to the surface where it will be collected directly into the sample containers. 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 field work 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 The Record, EHD, and the California Regional Water Quality Control Board (RWQCB). G:\GROUNDZE\neRecord\workpluLdoe