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� J 15 January 2007 AGE-NC Project No. 99-0669 Page 7 of 10 in wells installed within HU4. 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 utilizing a 2-inch well surge block to assist in settling the filter pack. Additional sand will be added if settling occurs. A three-foot bentonite seal(%-inch 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 slowly pouring the bentonite pellets into the annulus and allowing them to settle on the filter pack. The bentonite pellets will be allowed to hydrate for a minimum of one-half hour prior to grouting. The 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. The grout will be placed by pumping through tremie pipe. A grouting inspection will be scheduled with SJCEHD personnel.The proposed ground water well construction diagrams are depicted in Figures 3 (HU2) and 4(HU4). Upon grout completion, an eigbt-inch diameter, flush mount, traffic rated, steel well box will be installed over the well casings and secured with a bolted,steel well box cover.A reference point will be marked on the top of each well head, and surveyed by a California licensed surveying engineer to the nearest 0.01 foot to determine the elevation relative to a surveyed benchmark and to determine GPS coordinates for tracking on the State Water Resources Control Board(SWRCB)GeoTracker database system. 3.1.2. Well Development Development will consist of a combination of bailing 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 ground water pumping utilizing a two-stage submersible pump to finish the removal of sediment. Development activities will be continued until field parameter (pH, electrical conductivity, and temperature)readings have stabilized. 3.1.3. Ground Water Sampling Procedures Ground water sample collection will be performed in accordance with CVRWQCB and SJCEHD guidelines. Advanced GeoEnviconmental,Inc.