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02 January 2009 AGE-NC Project No. 99-0682 Page 5 of 7 Laboratory reports for soil/or and ground water analysis, testing methods, laboratory quality assurance/quality control (QA/QC) reports, and sample chain of custody documentation will be presented in a report with findings and recommendations. All sampling tools and brass sleeves used for sample collection will be thoroughly rinsed with clean water after washing with a solution ofAlconox. All hollow stem augers will be steam-cleaned prior to advancement of each borehole. 3 .4 . WELL COMPLETION Soil boring MW12 will be single-completed as ground water monitoring wells utilizing 2-inch diameter Schedule 40 polyvinylchloride (PVC) 0.010-inch slotted well screen and blankwell casing. Based on geologic/hydrogeologic conditions, a 10-foot length of well screen is anticipated for installation of the monitoring well; the bottom of the screen interval will be placed at 70 feet bsg. A proposed well construction diagram is depicted on Figure 3 . After installing the well casing, filter pack material consisting of pre-washed #2/12 Lonestar sand will be added from the bottom ofthe 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 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, then hydrating them using approximately five gallons of tap water and allowing them to swell and hydrate for a minimum of one-half hour prior to grouting. ISI Remaining annular space will be filled to 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. Grout will be placed by pumping through a tremie pipe. A grout inspection will be scheduled with the EHD personnel at least forty-eight hours prior to drilling. 3 .5 . WELL DEVELOPMENT AND SURVEY Development of the proposed well will consist of a combination of bailing with a Waterra inertia pump 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 submersiblepump to finishthe removal of fine-grained sediment. Developmental purging activities Advanced GeoEnvironmental, Inc.