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01 January 2007 AGE-NC Project No. 97-0290 Page 2 of 3 grouted in a"traditional"manner.However,procedures for abandonment of remediation wells and remediation piping will have to be modified, due to development of the site and current conditions a the property. AGE requests a "variance" from the San Joaquin County Environmental Health Department for the modified abandonment. MONITORING WELL ABANDONMENT PROCEDURES For the six off-site monitoring wells, each well cover box will be removed and the well will be subsequently excavated or over-drilled to a depth of approximately 3 feet below surface grade. A truck-mounted drill rig equipped with 12-inch diameter hollow stem augers will be utilized. Each well will then be pressure-grouted; pressure (15-20 psi) will be applied to each well for approximately three minutes to ensure grout penetration into the filter pack. The top three feet will then be backfilled with neat cement. For well MW-2,the well box will be carefully removed from the top of the concrete bench and the well will be pressure-grouted.No drilling is feasible at MW-2, since the elevation of the well was raised 3 feet above surface grade during development. The grout mixture for all wells will consist of Type I/II portland neat cement and not more than 6 gallons of water per 94-poundsack of cement. REMEDIATION WELL ABANDONMENT PROCEDURES For the remediation wells and horizontal remediation piping,grout will be pumped via the horizontal piping at the manifold. Pressure (15-20 psi) will be applied to the entire system for at least five minutes to ensure grout penetration into each well filter pack. If necessary, additional grout will be pumped through the manifold after a short period of"stabilization". The grout mixture for remediation wells and horizontal remediation piping will consist of Type I/II portland neat cement and approximately 10 gallons of water per 94-pound sack of cement. A "thinner" grout will likely be required in order to appropriate abandon the remediation wells. WASTE MANAGEMENT Any waste generated during the abandonment procedures,including rinse water,will be placed into 55-gallon DOT drums and stored along the north side of the theater building pending disposal. Drums will be disposed within 30 days of abandonment. Advanced GeoEnviron mental,Inc.