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' 62 MW-450D Exploratory Boring ' The electrical geophysical log was used in conjunction with the lithologic log of the MW-450D exploratory boring to identify the permeable zones of the intermediate zone and to design the screen intervals for wells MW-450S and MW-450D. The 16- inch normal, 64-inch normal, focused guard and single-point resistivity logs indicated two lenses of coarser sediment interbedded with finer sediment. ' The poorly-graded fine to medium sand characterized from 140 to 160 ft bgs in the lithologic log corresponded with a peak resistivity of 56 ohm-meters measured on the focused guard log at 147 ft bgs(Figure 4). The screen interval for well MW-450S ' was designed to extend from 140 to 155 ft bgs to include the poorly-graded fine to medium sand in that interval. ' The poorly-graded fine sand characterized at 170 ft bgs in the lithologic log corresponded with the peak resistivity of 83 ohm-meters measured on the focused guard log at 173 ft bgs (Figure 4). The screen interval for well MW-450D was designed from 166 to 176 ft bgs to include the poorly-graded fine sand characterized in that interval. ' 7.0 Well Construction 7.1 Well MW-449D ' Well MW-449D was constructed with 4-inch diameter flush-threaded schedule 40 PVC casing. The bottom of the well was set at 185 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 i 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 set from 180 to 1.65 ft bgs. The annular filter pack was set from 180 ft bgs to 159 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. The well was swabbed with a surge block to collapse any bridging of the filter pack while it was installed. After the filter pack was set at the target depth ' of 159 ft bgs, three feet of No. 60 transition sand was set above the filter pack to 156, ft bgs. Thirteen feet of time-release bentonite pellets was set above the transition sand to 143 ft bgs. A neat cement mixture was set from 143 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-449D is included in Figure 5. ' The casing for well MW-449D 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 MWA50 7128.9 SPX Cooling Technologies Dudek Stockton,California Page 4 January 2013