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1 Following the placement of the sand pack, Woodward Drilling developed the well by the surge and purge method Following well development, three feet of hydrated bentonite chips were placed within the annular space between the borehole and the well casing A surface seal of neat cement grout was placed over the hydrated bentonite, under SJCEHD observation The top of the well was secured with a water-tight locking cap and an 8-inch diameter, traffic-rated utility box On April 20, 2005, Morrow Surveying (California Licensed Land Surveyor#5161) surveyed the newly-installed well into the existing monitoring well network Morrow Surveying located the well jand measured the elevation of the top of the well casing to the nearest 0 01 foot, referenced to the city of Stockton benchmark #113 (Elevation 19 51 feet) The surveyor's report is included as Appendix B 23 Remedial Feasibility Test Well Installations On February 23 and 24, 2005, under the supervision of Ramage Environmental, Woodward Drilling installed one nested vapor extraction well (SVE-1A/B/C) and one nested air sparge/soil vapor extraction well (AS-1ISVE-2B) in the vicinity of the former UST#3 (Figure 2) Both wells were installed with a BK-81 drilling rig and 10-inch diameter hollow-stem augers 2 3 1 Nested Soil Vapor Extraction Well Woodward Drilling installed the three-well soil vapor extraction well nest to a total depth of approximately 55 feet The nested well consisted of three casings in the same borehole All three of the wells consisted of two-inch diameter, Schedule 40, flush-threaded and machine-slotted (0 020-inch) PVC well screens and blank PVC casings The screen intervals spanned from 12 to 22 feet, 28 to 38 feet , and 44 to 54 feet bgs Woodward Drilling placed filter packs of Monterey#3 graded and washed sand around the screen intervals and approximately two feet above the tops of the screen intervals Overlying all three ' filter pack intervals, Woodward Drilling installed four-foot thick seals of hydrated bentonite Overlying the upper bentonite layer, the driller placed a surface seal of neat cement grout Each of the well casings was secured with a watertight locking cap, and the well nest was covered with an 18-inch diameter, traffic-rated, flush-mount street box • 7