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PROPOSED INVESTIGATION AND WORKPLAN The previous investigation results indicate the soil at this site is contaminated with TPHG, BTEX, and TOG. John P. Cummings and Associates (JPCA) , therefore, proposes to characterize the vertical extent of the soil contamination. The proposed tasks of the investigation are listed below: 1) Prepare a site health and safety plan. 2.) Obtain well drilling permits and contact U S Alert to mark any possible underground utilities. Notify the San Joaquin County Environmental Health Division (SJCEHD) 48 hours prior to initiation of field work. 3) Advance three soil borings which will be converted into 2 inch diameter monitoring wells to an approximate depth of 55 ft or ten feet into the saturated zone whichever occurs first, using a truck mounted drill rig and 8-inch diameter hollow-stem augers near the former Tank Pit area, as shown in Figure 2. The distance between wells will be 50 feet or more. The borings will be converted into wells, if groundwater is encountered at or above 45 feet, the boring will be advanced 10 feet below the existing groundwater level. The screened portion of the well will be fifteen feet in length, from the bottom of the well to approximately five feet above the existing groundwater level. Sand pack will extend 18 feet from the bottom of the well. Then three feet of Bentonite pellets for a seal will be place above the sand pack, the remaining portion of the well will be cement grout to approximately 1 foot below grade. A traffic proof vault will be placed at the well-head and a locking cap, with lock, placed on the casing to secure the well. The borings which will be converted into wells will be identified as MW-1, MW-2 and MW-3. A typical well construction diagram is enclosed as Figure 3. 4) Collect soil samples at each 5 ft level interval or at significant changes in lithology commencing at a depth of fifteen feet, using a split spoon tube sampler loaded with pre-cleaned brass tubes. It is assumed that the upper 15 feet is disturbed soil that is known to be backfill and would not provide meaningful data. A maximum of 18 soil samples are anticipated to be collected. 5) Sampling equipment will be decontaminated using tri-sodium 4