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%.s 20 January 2011 AGE-NC Project No. 02-0950 Page 2 of 3 WELL DESTRUCTION PROCEDURES On 29 and 30 December 2010, monitoring wells MW-1 through MW-7 were destroyed at the site, under EHD oversight, utilizing a CME-75 truck-mounted drill rig equipped with 8.25-inch diameter hollow stem augers. The drill rig and three-person crew were supplied by RSI Drilling, of Woodland, California. Prior to destruction activities, each well casing was sounded with a Solinst water level meterto ensure no obstructions were present in the casings.Subsequently,well boxes and caps were removed to expose the well casings. On-site monitoring wells MW-1, MW-2, MW-4, MW-6 and MW-7 were drilled-out to the total depth of each boring, using 8-inch hollow-stem augers. All original well construction materials were removed (including well casing, screen, filter pack and annular seal) to ensure that no residual contamination was sealed within the abandoned borehole. The remaining borehole was backfilled to surface grade with a grout mixture and completed at the surface with native soil. A ratio of three gallons of water for every 50-pound sack of portland cement was utilized to prepare the grout mixture. Off-site monitoring wells MW-3 and MW-5 were destroyed by grouting the well casings under pressure. The wells were fitted with a pressure tight adapter connected to a hose extending from a grout mixer. A grout mix ratio of approximately three gallons of water for every 50-pound sack of portland cement was pumped into each well casing under approximately 5-10 pounds per square inch (psi)of pressure.A 21-inch diameter area was excavated to a depth of approximately 4 feet bsg, around the well casing of well MW-5. The area around well MW-3, located in the roadway(Figure 2)was not excavated. The top three feet of each well casing was removed and the borings were grouted to the near surface using the portland cement grout mixture and either completed at the surface with concrete (MW-3) or backfilled with native soil (MW-5). Well construction materials and auger returns generated by drilling were containerized in properly labeled Department of Transportation (DOT)-approved model 17H 55-gallon drums and were stored on-site. NON-HAZARDOUS WASTE DISPOSAL On 06 January 2011 , approximately 3,160 pounds of soil cuttings and solid waste (i.e. well materials)were containerized in 55-gallon drums and were removed from the site by Slaby Environmental, Inc., of Borrego Springs, California. Non-hazardous solid waste was Advanced GeoEnvironmental,Inc.