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O8 July 1999 AGE-NC Project No. 95-0130 Page 8 of 10 8-inch diameter hollow-stem augers. Cuttings generated during drilling activities will be placed on plastic sheeting and covered. Rinseate will be containerized in properly labeled D.O.T. 55-gallon drums, and stored on-site in an area lacking public access. Disposal alternatives will be evaluated based on results of soil and water analysis. Soil samples will not be collected from replacement wells located near MW-I through MW-5; however,soil samples will be collected at five-foot intervals beginning at a depth of 15 feet bsg from all other proposed downgradient wells. Soil samples will be collected utilizing a California split- spoon sampler and brass sleeves. The sampler will be driven by dropping a 140-pound weight from a height of 30 inches (blow counts) and record the number of blow counts on the boring logs. Upon soil sample retrieval, the middle brass sleeve will be removed from the sampler. The ends of the brass sleeve will be immediately covered with Teflon or aluminum sheets, sealed with plastic end caps, secured with tape and immediately placed in a chilled container for storage pending transportation to a state-certified laboratory. Each sample sleeve will be labeled with the following: boring location, depth, time, date and sampler's initials. During sampling activities, sample duplicates will be monitored for the presence of organic vapor using a photo-ionization detector (PID: Thermo Environmental 580A, 10.0 eV, calibrated to isobutylene) and will be described on boring logs using the Unified Soil Classification System (USCS). All sampling tools and brass sleeves used for sample collection will be thoroughly rinsed with clean water after washing with a solution of Alconox. All hollow stem augers will be steam-cleaned prior to advancement in each borehole. 4.3. MONITORING WELL COMPLETION Following completion of monitoring well drilling, a 2-inch diameter, Schedule 40 PVC 0.020-inch slotted well screen and casing will be installed. Based on the depth of the boring and ground water table,a 20-foot length of well screen will be installed. It is anticipated that the well section will be placed across the top of the saturated zone with a portion of the well screen section extending five feet above the water table. After installing the well casing,filter pack material consisting of pre-washed#3 Lonestar sand will be added 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 (bentonite chips) will be placed above the filter pack to minimize Advanced GeoEnvironmental,Inc.