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The casing will be assembled, run into the bore hole and temporarily set on the bottom of the hole <br />to assure proper placement of the screened interval. Once the screened interval is determined the casing <br />string will be suspended properly from the drill rig. <br />The screened interval in each well will be filter packed with pre-washed, No. 3 sand from total <br />depth to approximately two feet above the top of the screened interval. The augers will be slowly <br />withdrawn from the bore hole as the filter pack material is added. Once the filter pack reaches the <br />appropriate depth, the well will be bailed to assure settlement of the filter pack. <br />After the filter pack is installed, a minimum one-foot thick bentonite seal will be placed above <br />the filter pack using bentonite pellets. The remaining augers will be withdrawn, and if necessary, distilled <br />water will be added to assist in hydrating the bentonite. <br />Once the bentonite is adequately hydrated, the remaining annular space will be backfilled with <br />a cement/bentonite mixture. Each well casing will be cut off to approximately six inches below ground <br />surface, fitted with a locking pressure cap , capped with a labelled PVC cap, and enclosed in a waterproof <br />vault box. <br />Well elevations will be surveyed following completion of all wells. <br />B.2.2 Monitoring Well Development <br />Monitoring wells will be developed using a combination of bailing, surging with a surge block, <br />and pumping with a submersible pump. A Smeal 5-T or similar type development rig will be used for <br />the development of the wells. Measurements of pH, specific conductivity and temperature of the well <br />development water will be taken at regular intervals. Development will proceed until these parameters <br />are stabile and the water is relatively free of sediment. A minimum of ten casing volumes of water will <br />be removed during the development of the wells. Water produced during development will be placed in <br />DOT-approved drums, sealed, labeled appropriately, and placed in a designated area on-site. The <br />disposition of each drum will be determined upon completion of laboratory analyses of groundwater <br />samples. All water and containers will remain the responsibility of Metropolitan Stevedore. A field <br />PROP06.005 <br /> B-4 <br />DAMES & NIOORE