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r 13 September 2010 AGE-NC Project No. 95-0109 Page 2 of 3 Monitoring wells MW-1, MW-4, MW-8, MW-9 and MW-14 were destroyed by over-drilling to their total depths and backfilling with neat cement. The majority of the remaining wells were destroyed by grouting the well casings under pressure and over-drilling each well to three feet below surface grade(bsg). Due to their locations and at the direction of the EHD, wells MW-2 and MW-20 were not over-drilled to three feet bsg. Prior to commencement of well destruction activities each well casing was sounded with a Solinst water level meter to ensure that no obstructions were present in the casings. Wells MW-1, MW-4, MW-8, MW-9 and MW-14 were drilled-out to their total depth using a CME-95 hollow stem auger drill rig equipped with 8-inch diameter 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 then backfilled to surface grade with a grout mixture (A ratio of six gallons water for every 94-pound sack of portland cement will be utilized in preparation of the grout mixture). The remaining wells were fitted with a pressure tight adapter connected to a hose extending from the grout mixer. The grout mixture was pumped into each well casing for five minutes under approximately 5-10 pounds per square inch (psi) of pressure. The well boxes were then removed and the wells were over-drilled to three feet bsg (except MW-2 and MW-20) using a CME-95 hollow stem auger drill rig equipped with 8-inch diameter or 12-inch diameter (EW-1) hollow stem augers. The top three feet of the well casings were then removed and the borings were grouted to the near surface using the portland cement grout mixture. On 27 July 2010, all underground remediation piping was removed from the site. Trenches were excavated using a bobcat skid-steer loader equipped with a rock breaking hammer. Once the piping was exposed it was removed and disposed of properly. Trenches were backfilled with excavated soil and completed at the surface with concrete. The well construction materials, soil cuttings, and rinseate were hauled off-site for disposal at Chemical Waste Management in Kettleman City, CA. and Instrat Inc. in Rio Vista, CA. Copies of the non-hazardous waste manifests are included in Appendix B. Advanced CcoEnvironmental,Inc.