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27 October 2009 AGE-NC Project No. 95-0128 Page 2 of 3 • Wells MW-8 through MW-10,and MW-13 through MW-17 were single completed as 2-inch ground water monitoring wells to 45 feet below surface grade (bsg). • Wells MW-11 AB and MW-12 AB were dual completed as independent 2-inch monitoring wells. Wells designated with an "A" were completed to a total depth of 45 feet bsg; wells with a"B" designation were completed to 60 feet bsg. • All four of the sites vapor extraction wells were completed as 2-inch wells. VW-1 was completed a depth of 50 feet bsg and VW-2 through VW-4 were completed to 35 feet bsg. • EW-1 and EW-2 were single completed as 6-inch ground water extraction wells to total depths of 45 and 55 feet bsg, respectively. PROCEDURES Well destruction activities were performed on 21 through 24 September and 28 through 30 September 2009 All Well Abandonment, Inc. of Placerville, California. Monitoring, vapor extraction, and ground water extraction wells were destroyed by either pressure grouting or over drilling using 8 or 12-inch augurs. 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 at the site were abandoned either by pressure grouting or over drilling. A total of 18 monitoring,vapor extraction and ground water extraction wells(MW-1 through MW-4, MW-6 through MW-9, MW-11 A &B,MW-12 A &B, MW-13, VW-1 through VW-4, and EW-1 and EW-2) was destroyed by over drilling techniques. Wells that were over drilled were first sounded for total depth and verify that the well was free of obstructions. After the total depth was confirmed, a five-foot column of Lapis Luster#3 Monterey Sand was used to fill the inside of the inside of the PVC casing. A guide rod was then lowered through the length of the well casing and secured in the column of sand. After the guide rod was tightly secured in the sand, hollow stem augurs (either 8 or 12-inch dependent on borehole diameter)were used to over drill the entire depth of the well. Once the augurs reached total depth an attempt was made to pull the entire length of the well casing from the borehole using the drill rig's wench assembly. If the attempt to remove all well casing failed,due to breaks in casing during over drilling,all augurs were removed,and a wood plug was inserted at the leading end of the first augur and claw bit, and the well was over drilled to its total depth. Upon completion of destruction activities the well boxes were removed and the boreholes were completed to surface grade using either native soil, concrete, asphalt patch or the required city median material.