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24 April 2013 AGE-NC Project No. 95-0135 Page 2 of 3 MW-6, MW-9, and MW-10 by pressure grouting techniques. PROCEDURES As required, a health and safety plan will be prepared in accordance with Occupational Safety and Health Guidance Manual for Hazardous Waste Site Activities(National Institute for Occupational Safety and Health Administration, U.S. Coast Guard and U.S. Environmental Protection Agency, 1985). Prior to drilling activities, each proposed drilling location will be clearly marked and an utility clearance obtained through Underground Service Alert. Well destruction boring permits will be obtained from SJCEHD and they will be notified a minimum of 72-hours prior to performance of field activities; additionally, and encroachment permit will be procured from the City of Stockton to access the locations of off-site wells MW-8, MW-9, and MW-10. Prior to destruction activities, all wells will be checked for total depth and integrity using a Solinst water level meter. Any obstructions found in the well will be removed. Ilk Wells MW-1A/B, MW-2A/B, MW-3A/B will bedrilled-out to one foot deeper then the total depth of the original soil boring utilizing 12-irich diameter hollow-stem augers; the augers �? will be centered on the deeper-screened well casings. Wells MW-4, MW-7, and MW-8 will be drilled-out to one foot deeper then the total depth of the original soil boring utilizing 8.25-inch diameter hollow-stem augers'For all drilled-out wells, the original well construction materials will be removed (including well casing, screen, filter pack, and annular seal) to ensure that no residual contamination is sealed within the abandoned borehole. Remaining boreholes will be backfilled to surface grade with neat cement and covered with concrete or asphalt, depending on the surrounding surface material. Wells MW-5, MW-6, MW-9, and MW-10 will be destroyed by pressure grouting techniques. For each well, the well box and cap will be removed to expose the well casing. Each well will be initially filled over its entire depth with a thick grout mixture (no less than 6 gallons of water per 94 bag of cement); all water forced out during the initial placement of the grout will be containerized and properly disposed. Once the well is filled with the grout mixture the well head will be fitted with a pressure tight adapter connected to a hose extending from a grout mixer. A thick grout mixture will be pumped into the well casing under „- +T approximatelT-1.5-20 pounds per square inch (psi) of pressure. The well will then be d 1 over-drilled to approximately 3 feet below surface grade (bsg) using a 20-inch diameter, - hollow stem auger or excavated. The top 2.5 feet of the well casing will then be cut and removed and grout will be used to fill the boring to approximately 0.5 feet above the top of the well casing. The remaining borehole will be backfilled to surface grade with neat Advanced CeoEnvironmental,Inc.