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28 December 2009 <br /> AGE-NC Project No. 97-0300 <br /> Page 2 of 3 <br /> well destruction permit(Appendix A).Well destruction activities were conducted by Gregg Drilling <br /> of Martinez,California.Prior to destruction each well casing was sounded with a Solinst water level <br /> meter to ensure that no obstructions were present in the casings. <br /> Once it was determined that each monitoring well was free from any obstructions,a mixture of neat <br /> portland cement was pumped into each well from a truck mounted grout hopper. Each batch of <br /> cement was prepared in the hopper using a ratio of seven,47 pound bags of cement and 21 gallons <br /> of clean water.After the pumped mixture reached the top of each well casing,the well was fitted and <br /> sealed with a 2-inch well-head attachment and pressurized at a minimum of 25 pounds per square <br /> inch for 10 minutes. <br /> After the well was properly pressure grouted,a vacuum truck system and crew from Gregg Drilling <br /> cleared(air-knifed)a 20-inch diameter area surrounding the PVC casing and removed all well boxes <br /> and soil to a depth of three (3) feet bsg. Once the area around the casing was cleared to the proper <br /> width and depth, the top three feet of the casing was removed and the void space was "mushroom <br /> capped"with the cement mixture a minimum of 1-foot above the removed casing depth. Cuttings <br /> removed during air-knifing were used to backfill the remaining void space to approximately one- <br /> half foot bsg.The remainder of the void spaced was filled with a mixture of concrete and completed <br /> flush to surface grade. <br /> All of the aforementioned wells were destroyed following the above procedures,with the exception <br /> of monitoring well MW-3. During air-knifing activities at well MW-3, two unknown metal pipes <br /> were encountered at a depth of approximately 1.5 feet bsg.As a safety precaution,and approved by <br /> Ms.Vicki McCartney,air-knife clearing was terminated and the top 1.5 feet of casing were removed. <br /> The remainder of the void space was filled with the neat cement mixture and then finished to grade <br /> with concrete. <br /> The residual soil not used to backfill well locations,along with the removed well casing,were hauled <br /> under uniform non-hazardous waste manifest to U.S. Ecology Nevada Inc., of Beatty Nevada. A <br /> copy of the waste manifest is included with Appendix B. <br /> i <br /> Advanced GeoEnvironmental,Inc. <br />