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r 29 July 1999 AGE-NC Project No. 98-0426 Page 4 of 6 4.1. SOIL BORING ADVANCEMENT Soil borings will be advanced to a depth of approximately 35 feet bsg using a truck-mounted drill rig and 8-inch diameter hollow stem augers. Auger returns will be stockpiled on plastic sheeting on the property adjacent to the east (123 East Park Street). 4.2. SOIL SAMPLING PROCEDURES Soil samples will be collected using a California split-spoon sampler loaded with three 2-inch by 6- inch brass sleeves. The sampler will be driven by dropping a 140-pound hammer from a height of 30 inches. The number of blows required to advance the sampler in 6-inch increments will be recorded on the boring log. Upon removal from the sampler,the ends of the lead sample sleeve will be covered with Teflon sheets, capped and sealed with tape. Each preserved sample sleeve will be labeled with the boring location, depth,time and date. Appropriately sealed and labeled samples will be placed on ice in a chilled container and transported under chain-of-custody procedure to a DHS- certified laboratory. Soils encountered in the borings will be visually classified by an AGE geologist in accordance with the Unified Soil Classification System (USCS). Additionally, soil samples with be field screened for the presence of volatile organic compounds using an organic vapor meter equipped with a photo- ionization detector (PID) precalibrated to isobutylene. 4.3. MONITORING WELL COMPLETION Following completion of drilling, a 2-inch diameter Schedule 40 PVC 0.020-inch slotted well screen and casing will be installed. A 20-foot section of well screen will be installed, extending approximately 15 feet below and five feet above the top of the ground water table. The filter pack material, consisting of pre-washed 43 Lonestar sand, will then be added extending from the bottom of the borehole to approximately two feet above the screened interval. Following placement of the filter pack, the well will be surged to assist in settling the filter pack. Additional sand will be added if settling occurs. A nominal two-foot bentonite seal will be placed above the filter pack to minimize the potential of grout penetration into the screened section of the well. The bentonite seal will be formed by pouring bentonite chips into the annulus and allowing them to settle on the filter pack. Bentonite chips will be hydrated using five gallons of water. The bentonite chips will be allowed to hydrate for a minimum of 20 minutes prior to grouting. The casing, filter pack and bentonite seal will be placed into the borehole through the interior of the hollow-stem augers. Advanced CcoEnv ironmental.Inc.