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July 14, 2014 <br /> Page 2 of 4 <br /> Reference: Well Destruction Report <br /> 7-Eleven Store #17334 <br /> 4501 North Pershing Avenue <br /> Stockton, California <br /> Well Destruction <br /> On May 15 through 20, 2014, Stantec supervised the destruction of four groundwater monitoring <br /> wells (MW-2, MW-3, MW74, and MW-5A/B) and two remediation wells (SPV-1 and SPV-2), by <br /> National Exploration, Wells, and Pumps (National EWP) of Richmond, California (Figure 2 and <br /> Table 1). <br /> Wells MW-5A/B, SPV-1, and SPV-2 were destroyed by overdrilling each well with hollow-stem <br /> augers to completely remove all well materials. Each void was then backfilled from total depth to <br /> the near surface with neat cement grout.The top of each void was finished with dyed concrete <br /> to match the existing grade. <br /> Due to the close proximity of underground utilities,wells MW-2, MW-3, and MW-4 were destroyed <br /> by pressure grouting, which consisted of:filling the well and filter pack with neat cement grout <br /> through a tremie pipe from total depth to top of the well casing.The grout was allowed to settle <br /> and then topped off before pressure was applied to the wells at 25 pounds per square inch for ten <br /> minutes. After applying pressure at MW-2 and MW-3, each well box was removed and the area <br /> around each well was cleared to.a depth of 2.5 feet below ground surface (bgs). Each casing <br /> was cut at two feet bgs and grout was poured in to surround the casing and create a "mushroom <br /> cap" around the well casing.The surface was finished with dyed concrete to match existing <br /> grade. <br /> Due to the presence of high-voltage electric lines running directly under the well box at MW-4,.the <br /> well box was left in place.The metal ring at the top of the well box was removed and the well box <br /> was filled with concrete to the surface. <br /> Approvals to pressure grout MW-2, MW-3, and MW-4, and to leave the well box in place at MW-4 <br /> were granted by the SJCEHD in emails dated May 9, 2014,and May 19, 2014 (Attachment A). <br /> Copies of the field notes summarizing well destruction activities are provided in Attachment C. <br /> Copies of the California Department of Water Resources (DWR) Well Completion Reports are <br /> provided in Attachment D. <br /> Design with community in mind <br />