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

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' 7.4 Well MW-450S ' Well MW-450S was constructed with 4-inch diameter flush-threaded schedule 40 PVC casing. The bottom of the well was set at 160 feet below ground surface(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 155 to 140 ft bgs. ' The annular filter pack was set from 157 ft bgs to 136 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 136 ft bgs, three feet of No. 60 transition sand was set above the filter pack to 133 ft bgs. Eleven feet of time-release bentonite pellets was set above the transition sand to 122 ft bgs. A neat cement mixture was set from 122 ft bgs to land surface(Table 1). An as-built diagram of well MW-4505 is included in Figure 8. The casing for well MW-450S 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. 8.0 Initial Water Levels and Well Development ' The initial water levels at each well were measured the day the wells were developed on July 9 and 10, 2012. The first stage of well development included surging and bailing with a single surge block and a 3.5-inch diameter, 6-feet long stainless steel bailer(3 ' gallon volume). The bailer was used to remove drilling mud and heavy sediment (i.e. sand). The second stage of well development included pumping with a 3-inch diameter submersible pump. The submersible pump was first lowered approximately 10 feet ' below the water level and pumped to remove suspended solids from the well. The submersible pump was then lowered to the bottom of each well and raised gradually over the screen interval to remove drilling mud and fine sediment from the filter pack and ' enhance the hydraulic connection between the well and the native formation of the intermediate zone. ' An In-Situ Inc. Troll 9500 multiparameter monitoring and logging probe was used during the pumping phase of development to measure and record pH, temperature in degrees Celsius, specific conductivity in micro Siemens per centimeter(uS/cm), oxidation- reduction potential in millivolts (mV), turbidity in Nephelometric Turbidity Units (NTU), and dissolved oxygen in milligrams per liter(mg/L). The Troll 9500 was set in a flow- through cell with the development water pumped through the cell at an average rate of approximately 19 GPM. A totalizer in the flow line was used to measure the total gallons pumped during the development phase. The total gallons pumped during development ' ranged from 500 gallons at well MW-450D to 1,345 gallons at well MW-4505. The Troll 9500 was calibrated at the beginning of each day using a calibration kit ' supplied by In-Situ. Well Completion Report for Monitor Well Pairs MW-449 and MWA50 7128-9 SPX Cooling Technologies Dudek ' Stockton,California Page 6 January 2013