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2.1 Drilling and Well Installation Prior to being damaged,well MW-17 was a 2-inch Schedule 40 well completed to a depth of 23 feet below ground surface. Sampling records indicate that this well had been installed in early May 1991;however, construction records for this well are not known to exist. Depth to water in this well has always been greater than 10 feet below top of casing(which is near ground surface). The well is largely intact; however, attempts to develop it in July 2010 resulted in the production of filter pack sand,indicating that the well screen had been damaged. Since the well is mostly intact,it will be overdrilled to 23 feet below ground surface (the depth of the existing well)using 4 '/<-inch ID (approximately 8-inch OD)hollow-stem augers and the existing well casing and screen will be removed. The replacement well will be installed in the same borehole and will be constructed using new materials. Well construction will be performed within the hollow-stem augers. The well screen will consist of 10 feet of 2-inch diameter 10-slot flush joint threaded Schedule 40 PVC with an end cap. The bottom of the screen will be placed at a depth of 23 feet. The well casing will extend to ground surface and will consist of 2-inch diameter flush-joint threaded Schedule 40 PVC with a locking cap. After the well screen and casing are placed, a filter pack, consisting of 10/20 mesh silica sand will be poured through the augers to a depth of approximately 11 feet(two feet above the top of the well screen. A tow foot-thick bentonite seal will be place on top of the filter pack to an approximate depth of 9 feet below ground surface. The remainder of the annular space will be backfilled with cement grout conforming to ASTM D5092. The well is located in the landscaping materials outside of the office area and as such is not subject to traffic disturbance. It will be protected from access and physical damage using a bolted 8-inch diameter well vault that will be grouted in a small concrete apron to promote drainage away from the well. 2