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Mr. Andrew A. Woods 14 September 1998 Page 2 PROPOSED SCOPE OF WORK Task 1 -Install Two Monitoring Wells Monitories Well Design Two monitoring wells will be installed at the approximate locations shown on Figure 1. The wells will be 2-inch PVC casing with locking caps and will be completed within steel standpipes that extend approximately 6 inches above grade. All pure will be responsible for installing the posts around the wells. The shallow well will be designed to match the existing wells and will be screened over the interval of 10 to 18 feet below the ground surface. The deep well will be screened from a depth of 25 to 35 feet below the ground surface, unless a clay confining layer is found at a shallow depth than 35 feet. Well screens will be fabricated with 0.010-inch factory cut slots. The annual space around the well screen will be filled with appropriately sized sand that will extend three feet above the well screen. A three-foot bentonite seal will be placed above the sand. The remaining annular space will be filled with a cement grout. The well will be completed in a vault with a locking cap. The well locations will be surveyed and tied in to the existing well network. Well Installation Borings for the wells will be drilled by hollow stem auger methods using 8-inch diameter augers. Soil samples will be collected from each borehole at five-foot intervals, beginning at the ground surface for logging and analytical purposes. Samples will be collected by advancing the auger to a point immediately above the desired sampling depth interval and then driving a modified California split-spoon sampler lined with three brass tubes into the undisturbed soil. The sampler will be driven using a 140-pound hammer with a 30-inch free-fall drop, in accordance with ASTM Standard Method D1586-84, "Penetration Test Split Barrel Sampling of Soil." Blow counts will be recorded in six-inch intervals for every sampling event. To minimize the potential for cross-contamination, all augers and associated equipment will be cleaned with a high-pressure hotwater washer prior to drilling each boring. The split-spoon sampler, associated sampling equipment and brass sample tubes will be cleaned with a trisodium phosphate wash and rinsed with water prior to collecting each soil sample. Collection of Soil and Groundwater Samples for Laboratory Analyses One soil sample collected from above the top of the uppermost saturated zone will be selected for analysis from the two groundwater monitoring well borings. This depth is expected to be 10 feet below the ground surface, but the actual depth may vary because of the recent rainsAfter the soil sample is retrieved from the split-spoon sampler, the ends of the middle sample tube will be sealed