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A1.0 Drilling Methodologies Barings will be advanced using a hollow-stem auger. The minimum inside diameter (ID) for the 4-inch extraction well (EW-3) will be 6 inches. The minimum ID for the 2-inch monitoring/product recovery wells (MW-20 and MW-21) will be 4 inches. A wooden knock-out plug will be used, if necessary, to prevent heaving sands from entering the auger during well construction. The extraction well boring will be advanced to depth of 40 feet (for a 35-foot well completion). The boring for the monitoring/product recovery wells will be advanced to approximately 35 feet(for a 30-foot well completion). The monitoring well depths are intended to avoid having the wells go dry as a result of pumping in the adjacent recovery wells. AU Well Construction During well construction, all downhole measurements will be reported to the nearest 0.10 foot from a stable datum. All casing and screen will be held in tension during well construction. A minimum of two centralizers will be used for each extraction well (at the top and bottom of the screened interval, at a minimum). Following installation, distances from each of the well locations will be measured parallel and perpendicular from the nearest permanent building corner. Well elevations will be measured using an engineer's level, using the top of existing monitoring well MW-3 as a datum. The following subsections describe recovery and monitoring well construction. Al.1.1 Recovery Well Construction Well EW-3 will be constructed to a depth of approximately 35 feet bgs. The well will be constructed from 0 to 10 feet bgs using nominal 4-inch diameter Schedule 40 PVC blank casing. A total of 20 feet of 4-inch, 0.030-inch opening PVC well screen will be installed from 10 to 30 feet bgs, with a 5 foot Schedule 40 PVC sump to the total well depth of 35 feet. A filter pack consisting of No. 3 silica sand will be carefully poured through the augers as they are removed. The top of sand will be maintained at a maximum of 3 feet below the bottom of the augers as they are withdrawn from the boring. The top of the sand filter pack will installed to about 2 feet above the top of the well screen. Prior to placement of bentonite, the wells will be briefly surged, using a bailer or surge block, to settle the filter pack. The top of the filter pack will be measured again and the process will be repeated until filter pack settlement is less than 0.10 feet. After measurements confirm that settlement has been minimized, a 3-foot thick bentonite seal will be placed above the filter pack by pouring through the augers. The bentonite will be allowed to hydrate for a minimum of 45 minutes before grouting. The bentonite seal will be hydrated with potable water at a rate of 5 gallons per foot of bentonite. A concrete grout seal will be mixed and placed from the top of bentonite to ground surface in accordance with ASTM D5092. The grout seal will be allowed to cure for a minimum of 24 hours before any well disturbance. The surface completion will be installed in a flush-mount, traffic-rated vault. A1.1.2 Monitoring Well Construction Wells MW-20 and MW-21 will be constructed to a depth of approximately 30 feet bgs. The well will be constructed from Oto 10 feet bgs using nominal 2-inch diameter Schedule 40 PVC blank casing. A total of 20 feet of 2-inch 0.020-inch machine slot Schedule 40 PVC well screen will be installed from 10 to 30