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19 March 2004 AGE-NC Project No. 02-0886 Page 6 of 8 4.1. SOIL BORINGS AND SAMPLING Up to three soil borings may be advanced at the site to a depth of 70 feet bsg utilizing a truck- mounted CME-75 drill rig equipped with 8.25-inch hollow-stem augers. Three pilot borings will then be completed as ground water monitoring wells, if necessary. Soil will be collected ahead of the lead drill auger with a three-inch wide core barrel. Soil samples will be collected from each soil boring at five-foot intervals. Relatively undisturbed soil samples will be collected in each of the borings using a 2-inch diameter by 6-inch long brass sleeves. The exposed ends of the soil sleeve will be covered with Teflon sheets, capped and sealed with tape. Soils sampled in the borings will be visually classified by an AGE geologist in accordance with the Unified Soil Classification System (USCS). Additionally, soil samples will be field screened for the presence of volatile organic compounds using an organic vapor meter(OVM) equipped with a photo-ionization detector(PID: Thermo Environmental 580B, 10.0eV [or equivalent], calibrated to isobutylene). Soil sample descriptions and OVM readings will be recorded on a log for each boring. Following sample collection,each preserved sample sleeve will be labeled with the boring location, depth,time,date and sampler's initials. Appropriately sealed and labeled samples will be placed in a chilled container under ice and transported under chain-of-custody procedure to a DHS-certified laboratory. 4.2. WELL COMPLETION AND WELL ELEVATION SURVEY The 8.25-inch diameter pilot borings will be single-completed as ground water monitoring wells utilizing one 2-inch diameter schedule 40 polyvinylchloride (PVC) 0.020-inch slotted well screen and blank well casing. A 20-foot length of well screen is anticipated for installation of the monitoring well. A proposed monitoring well construction diagram is depicted in Figure 3. After installing the well casing in each boring,a filter pack material consisting of pre-washed#2/12 Lonestar sand will be added through the augers over the screen interval 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(non-coated bentonite pellets)will be placed above the filter pack to minimize the potential for grout penetration into the screened section of the well. The bentonite seal will be formed by pouring bentonite pellets into the annulus and allowing them to settle on the filter pack.The bentonite pellets will be allowed to hydrate for up to one-half hour prior to grouting. The remaining annular space will be filled within one foot of the ground surface with a cement grout. The grout mixture will consist of Type I/II portland neat cement and not more than 6 gallons of water per 94-pound sack of cement. The grout will be placed by pumping through tremmie pipe. A Advanced GeoEnvironmental,Inc.