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05 December 2007 AGE-NC Project No. 97-0327 Page 6 of S 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. 3.3. WELL COMPLETION Soil boring MW-5 will be completed as a ground water monitoring well utilizing 2-inch diameter schedule 40 polyvinylchloride (PVC} 0.020-inch slotted well screen and blank well casing. Based on geologic/hydrogeologic conditions, a 20-foot length of well screen is anticipated for installation of ground water monitoring well MW-5; a proposed well construction diagram is depicted in Figure 3. After installing the well casing, filter pack material consisting of pre-washed #2112 Monterey 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 three-foot transition seal (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 chips will be allowed to hydrate a minimum of one-half hour prior to grouting. The remaining annular space will be filled to within 1 foot of the ground surface with a cement grout seal. The grout mixture will consist of Type 1/I1 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 grouting inspection will be scheduled with SJCEI-1D personnel. A traffic-rated well box will be installed over the top of the well casing. 3.4. WELL DEVELOPMENT Development of the proposed well will consist of a combination of bailing with a stainless steel bailer to remove the major portion of fine-grained sediment from inside the well, surging to flush out or draw in sediment from the filter pack and additional ground water evacuation{purging) with a submersible pump to finish the removal of fine-grained sediment.Developmental purging activities will be continued until field parameter(pH,electrical conductivity, and temperature)readings have stabilized and purged water is visually sediment-free. Advanced GeoEmironmentai,Inc.