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• <br /> WELL INSTALLATION AND DEVELOPMENT PROCEDURES <br /> BECK DEVELOPMENT SITE <br /> • Tracy,California <br /> • The fourth groundwater monitoring well at the Beck Development site will be drilled using <br /> the hollow stem auger technique. Drill cuttings will be inspected and the stratigraphy <br /> logged by an AEMC staff geologist. Maximum well depth will be twenty-five feet and the <br /> well will be constructed by installing flush threaded, four-inch schedule 40 PVC casing and <br /> • factory slotted 0.010-inch well screen down through the hollow stem of the auger. The well <br /> will be screened from five feet below grade to the bottom of the well boring. The sand <br /> pack will be placed by backfilling the annulus between the borehole wall and the well <br /> casing with Lonestar 1/20 mesh sand as the auger casing is retracted. <br /> • A two foot bentonite seal will be placed above the sand pack, followed by a <br /> cement/bentonite grout seal to the surface. The bentonite grout seal will be placed in the <br /> same manner as the sandpack. The well will then be completed above grade and enclosed <br /> inside a locking monument box. A typical monitoring well completion diagram is included <br /> • as Attachment 1, Monitoring Well Design. <br /> Approximately 24 hours after installation, the monitoring well will be developed by <br /> swabbing the inside of the well with a surge block in a plunger-like fashion and then <br /> pumping the wells with a submersible pump until the discharge water clears. This <br /> procedure is repeated twice. Surging will also take place during the pumping phase of <br /> development by turning off the submersible pump (with its check valve removed) <br /> intermittently during pumping. <br /> • <br /> • <br /> • <br />