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26 March 2012 AGE-NC Project No. 99-0592 Page 2 of 3 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. Also to be submitted with this work plan, are the monitoring well destruction permits and associated fees,and the SJCEHD Master File Record (MFR)information form to expedite the well destruction activities. Prior to destruction activities, wells will be checked for total depth and integrity using a Solinst water level meter. Any obstructions found in the well will be removed. ?v Wells MW-1 and MW-8 will be drilled-out to one foot deeper then the total depth of the well utilizing 8.5-inch diameter hollow-stem augers for well MW-1 and utilizing 10.5-inch diameter hollow-stem augers for well MW-8(four inch casing).All 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. Well boxes and caps will be removed to expose the well casings of wells MW-2 through MW-7. Well heads will be fitted with a pressure tight adapter connected to a hose extending from a grout mixer.A thin grout mixture (to easily penetrate the screen openings of the casing under pressure) will be pumped into the well casing under an approximate pressure of 20 pounds per square inch (psi)over a minimum of ten minutes. Wells will then be over-drilled to approximately 3 feet bsg to a thickness of at least one foot larger in diameter than the original boring diameter using hollow stem augers (approximately 20-inches wide). 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. Remaining boreholes will be backfilled to surface grade with neat cement and covered with concrete or asphalt, depending on the surrounding surface material. Soil cuttings generated during drilling activities and rinseate will be containerized in properly labeled Department of Transportation (D.O.T.)-approved 55-gallon drums or a landfill disposal container, and stored on-site for proper disposal. Upon completion of field work and disposal of soil-cuttings, a well destruction report describing well destruction activities and procedures, including documentation of waste disposal from well destruction and other activities will be prepared and submitted to the Central Valley Regional Water Quality Control Board (CVRWQCB) and SJCEHD.