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Field Activities Groundwater monitoring wells MW-9, MW-1 1 through MW_13, MW-14A;MW-16, MW-1.9, MW-20, MW-24, MW-25, VM- 1, VM-2,_-and ASW-1 through ASW-4 will be destroyed by pressure grouting the casing and annulus to-the total depth of each well. The sealing material will consist of neat cement with a 5% mixture of bentonite: The cement wily be introduced:with a tremie'pipe extending to the bottom of each monitoring well. Wells MWa9, MW-11 through.MW-13,.MW-14A, MW716, MW-19, MW-20, MW724 and MW725 are 4-inch-diameter wells and rang_e in depth from 60,to 91 feet. Wells VM-1 and VM-2 are 2-inch-diameter wells and are 60feet deep. Wells ASW-1 through ASW-4 are 1- inch-diameter wells and range in depth.from 72 to 96 feet.Well'concentrations details are presented on Table 1. After the wells are grouted to a depth of approximately'! feet below the ground surface, we will utilize a backhoe to remove the upper 3'feet of casing and the soil from an area 12 inches larger than the original boreholes. Once the soil has been removed, additional'grout.will be added to the casing and allowed to."mushrbom" over the.casing and-into the`surrounding 346ot=deep excavation. The excavation will then.be backfilled with soil and concrete to the ground surface. Black dye will be .applied to the concrete at the ground surface iii order to•blend with the surrounding asphalt. Per SJCEHD;requirements, due to minor contamination remaining in wells VEW-1 and VEW-2, these ' wells will be destroyed by overdrilling the casing'and annulus to the total depth of each well. Wells VEW-1 and YEW-2'are 6-inch-diameter wells and are 40 feet deep. After.removal-of the casing and annulus from each well,the wells will be backfilled with neat'cement as described above. The excavated soil wiltbe contained`in labeled Department of Transportation-approved, 55-gallon -drums and stored .temporarily onsite'until transportation to -an appropriate disposal facility'can be arranged. The well casing will be placed in a waste receptacle. Report Preparation A Well Destruction Report will be prepared to.transmit the field data. The Report will include (but not be limited to) the following: Project description Field observations Appendices including the SJCEHD Well Destruction Permit Vicinity Map arid.Site Plan indicating.the former-well locations We will"also submit.copies of completed California Department of Water Resources (DWR) Well _ Completion Reports for.each destroyed well under separate cover. Shop 10 Maintenance Station,Task Order No.94 Caltrans Contract 06Al1141,8A 43-910076 Project No.59200-06-94 -2 - June 29,2010