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r - 29 July 2013 AGE Project No. 95-0135 Page 2 of 3 PROCEDURES Well destruction activities were performed on 28, 29, 30, and 31 May 2013 and 03 and 04 June 2013 by All Well Abandonment of Sacramento, California. 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. /411 kdal Abd n�ayT:�c..lr S�y.r d S Well MWAA/B was drilled-out to a depth of 75 feet bsg and wells MW-2A/B and MW-3A/B were drilled-out to one foot below total depth of the wells using a CME-75 truck-mounted drill rig equipped with 12.2rnch.diameter hollow stem augers; refusal was encountered at 75 feet below surface grade (bsg) in MWAA/B and the EHD approved terminating drilling activities at 75 feet bCg. For the destruction of nested wells MW-1A/B, MW-2A/B, MW-3A/B, the augers were centered on the deeper well using a stinger bit. Additionally, wells MW-4, MW-7, and MW-8 were drilled-out to one foot below total depth of the wells using either a CME-75 truck-mounted drill rig or limited access drill rig (LAR); both drill rigs were equipped with 8.25-inch diameter hollow stem augers. All well boxes were removed during the over-drill process. All original well construction materials were removed (including well casing, screen, filter pack, and annular sea[) to ensure that no residual contamination was sealed within the abandoned borehole. Following over-drilling,each well was grouted to near surface using a Portland cement grout mixture (A ratio of six gallons water for every 94-pound sack of Portland cement was utilized in preparation of the grout mixture); the surfaces at each location were then completed with a rapid setting concrete mixture. Wells MW-5 MW-6, MW-8, and MW-9 were destroyed by grouting the well casings under pressure and over-drilling each well to three feet bsg. The well caps were removed to expose the well casing. Each well was initially filled over its entire depth with a Portland cement grout mixture (A ratio of six gallons water for every 94-pound sack of Portland cement was utilized in preparation of the grout mixture). All water displaced during the initial placement of the grout was containerized in properly labeled, Department of Transportation (D.O.T.)-approved 55-gallon drums and stored on-site for proper disposal. The wells were then fitted with a pressure tight adapter connected to a hose extending from the grout mixer.The Portland cement grout mixture was pumped into each well casing for five minutes under approximately 20-25 pounds per square inch (psi)of pressure. The well boxes were then removed and wells MW-5, MW-6, MW-8,and MW-9 were over-drilled to three feet bsg using an 18-inch diameter asphalt cutter and widened to 20 inches in diameter by hand clearing to three bsg. The top 2.5 feet of the well casings were then removed and the borings were filled with the grout mixture to near surface. The surfaces at each location were then completed with a rapid setting concrete mixture. Advanced GeoEnvironmental,Inc.