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07 January 2013 AGE-NC Project No. 98-0500 Page 3 of 4 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. Wells will be drilled-out to one foot deeper then the total depth of the well utilizing 8.5-inch diameter hollow-stem augers for wells. 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. Pressure grouting will entail the following: well boxes and caps will be removed to expose the well casings of the grouted well. 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 within the contaminated soil plume area, will be stored on-site pending disposal in bulk (secured in plastic) or placed into a pile for landfill disposal or transportation bin for land fill disposal,which ever has been determined to the most cost effective and protective of the environment. Clean soil or soil drilling occurring outside the apparent contaminated soil plume, may be piled on-site for fill material and tilled into site soil. All liquid 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. Soil vapor and air-sparge piping will be removed from the site surface and underground piping will be capped with grout portland cement. The soil vapor extraction equipment will be removed and either salvaged or recycled, if appropriate. REPORTING 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.