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Mr. Gerald Djuth, P.E. November 3,2003 Page 4 Well Construction One boring location believed to be free from impacts (based on odor)will be completed as a monitoring well and will be constructed and developed in accordance with ASTM D 5092-90 using threaded, 1-inch PVC with 10 feet of 10-slot screen to limit silt production. The well will be completed with a PVC slip cap. The anticipated boring depth will be about 18 feet,with the screen positioned to straddle the water table (anticipated at about 10 feet below grade)at about midpoint. The filter pack will consist of 10/20 silica sand (compatible with formation materials and the selected screen size) and will be poured to two feet above the top of the screen. A two-foot thick bentonite seal will be placed on top of the sand and a minimum 5-inch diameter Portland/bentonite grout seal (to allow for a 2-inch annular seal)will be placed by pouring. It will extend from the top of the bentonite seal to ground surface. Surface completion will consist of a traffic-rated, flush-mounted vault. Up to 5 casing volumes will be removed from the well during development,using a disposable, polyethylene bailer and/or a peristaltic pump. Boring Abandonment and Waste Disposal After the borings have been completed and sampled,they will be abandoned by backfilling with ' cuttings and/or bentonite chips. Because concentrations are expected to be low in downgradient locations, excess cuttings will be disposed in an on-site LFC dumpster. Liquids generated during sampling will be contained and transported to the LFC oil-water separator for subsequent treatment in the on-site wastewater treatment system. Groundwater Sampling A groundwater sample will be collected from the new monitoring well and at selected locations described above. Sampling from the well will be preformed after the completion of development. If sampling immediately follows development, additional purging will not be required, provided that pH, temperature and conductivity measurements from the final three casing volumes are all within 15%. Purging may be performed using a disposable bailer,peristaltic pump with new and/or dedicated polyethylene and silicone tubing, or other equivalent method. When stable conditions have been documented, a groundwater sample will be collected and submitted to Sequoia Analytical in Sacramento for diesel hydrocarbon analysis by DHS LUFT. Samples will be transferred directly into laboratory-supplied containers. Samples collected directly from the Geoprobe borings will be transferred directly into laboratory-