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• If no groundwater contamination is detected in boring #2, boring #3 will be drilled downgradient of GT-3 (Figure 2). The same procedures will be followed as in drilling boring 2, and if no groundwater contamination is detected in boring#3, it will be completed as monitoring well GT-5. Borings 4 and 5 will be drilled to further delineate the extent of soil contamination on the Gilliew property. Based on previous work, both of these borings are expected to penetrate several feet of slightly contaminated soil near the margins of the soil plume. Depending on the time available, the groundwater samples and some of the soil samples may be archived for later analysis in the stationary laboratory. At present, we estimate that a total of 25 soil samples and 5 water samples will be analyzed. The two monitoring wells will be constructed of 2-inch-diameter PVC casing. The screened interval will be from 80 feet to 60 feet. Details of the well construction are shown in Figure 3. Upon completion of all field and laboratory work, an assessment report will be prepared by a California registered geologist. The report will be include recommendations regarding future site investigations. 4.0 PROCEDURES 1)Notify San Joaquin EHD at least 48 hours prior to field work. 2)Drill five vertical borings to depths of 65 to 70 feet below grade using a hollow-stem auger drilling rig. 3)Collect discrete soil samples at 5-foot intervals,using a California modified split-spoon sampler loaded with three 6" brass sample sleeves. 4)Preserve the bottom sleeve by covering the ends with teflon sheets and plastic caps, and deliver to the on-site laboratory for analysis of TPH-g, TPH-d, and BTEX. 5) Screen the middle sample for the presence of organic vapors using a portable photo-ionization detector(PID) and record the measurement on the boring log. 6)Extrude the middle and upper sleeves and record the sample descriptions on the boring log in accordance with the Unified Soil Classification System. 7)Decontaminate the sampling equipment between samples. 8)Use a hydropunch-type sampling device to collect a groundwater sample from each boring. Place the sample in sterilized vials and amber bottles for laboratory analysis. 9) Steam clean the drilling equipment between borings. 10)Place auger returns on visquine.