ARCHIVED REPORTS_WELL COMPLETION REPORT MW 4495D AND MW 4505D 20130301

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' 7.2 Well MW-4495 ' Well MW-4495 was constructed with 4-inch diameter flush-threaded schedule 40 PVC casing. The bottom of the well was set at 159 ft bgs. The bottom 5 feet of the well was a blank, 5-foot section of schedule 40 PVC casing(i.e. sump). The well ' screen was constructed with 4-inch diameter schedule 40 PVC casing perforated with 0.020-inch slots. The well screen was threaded to the 5-foot sump and was set from 154 to 139 ft bgs. IThe annular filter pack was set from 157 ft bgs to 133 ft bgs and consisted of Monterey No. 3 (8x20) sand. The filter pack sand was tremied into the annulus. The ' top of the filter pack was checked with a weighted engineer's tape as the filter pack was installed. After the filter pack was set at the target depth of 133 ft bgs, two feet of No. 60 transition sand was set above the filter pack to 131 ft bgs. Ten feet of time- release bentonite pellets was set above the transition sand to 121 ft bgs. A neat cement mixture was set from 121 ft bgs to 90 ft bgs. Bentonite pellets were installed from 90 ft bgs to 80 ft bgs to seal the borehole from the shallow zone. A neat cement mixture was then set from 80 ft bgs to land surface(Table 1). An as-built diagram of well MW-4495 is included in Figure 6. The casing for well MW-449S was trimmed to a final elevation below ground surface and a 12-inch diameter traffic rated well vault was installed in concrete with the final rim and lid elevation crowned approximately one inch above grade. ' 7.3 Well MW-450D Well MW-450D was constructed with 4-inch diameter flush-threaded schedule 40 ' PVC casing. The bottom of the well was set at 181 ft bgs. The bottom 5 feet of the well was a blank, 5-foot section of schedule 40 PVC casing(i.e. sump). The well screen was constructed with 4-inch diameter schedule 40 PVC casing perforated with ' 0.020-inch slots. The well screen was threaded to the 5-foot sump and was set from 176 to 166 ft bgs. ' The annular filter pack was set from 177 ft bgs to 162 ft bgs and consisted of Monterey No. 3 (8x20) sand. The filter pack sand was tremied into the annulus. The top of the filter pack was checked with a weighted engineer's tape as the filter pack ' was installed. After the filter pack was set at 162 ft bgs, four feet of No. 60 transition sand was set above the filter pack to 159 ft bgs. Eleven feet of time-release bentonite pellets was set above the transition sand to 148 ft bgs. A neat cement mixture was set ' from 148 ft bgs to 58 ft bgs and allowed to set overnight. Bentonite pellets were installed the next day from'58 ft bgs to 32 ft bgs to seal the borehole from the shallow zone. A neat cement mixture was then set from 32 ft bgs to land surface (Table 1). ' An as-built diagram of well MW-450D is included in Figure 7. The casing for well MW-450D was trimmed to a final elevation below ground surface ' and a 12-inch diameter traffic rated well vault was installed in concrete with the final rim and lid elevation crowned approximately one inch above pavement grade. Well Completion Report for Monitor Well Pairs MW-449 and MW450 7128-9 SPX Cooling Technologies Dudek ' Stockton,California Page 5 January 2013