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Well Destruction Work Plan University Park 1252 North Stanislaus Street Stockton,CA Page 2 be pumped into the well through the center of the augers, starting at the bottom of the hole and moving upward to the surface. The grout will be placed in one continuous operation if possible. Any groundwater displaced to the ground surface will be collected and contained in approved Department of Transportation (DOT) drums, sealed, labeled,and characterized for disposal. Monitoring wells MW-6 and MW-9 will be abandoned in place by filling the wells with a neat-cement grout slurry to displace the water in each well. The traffic boxes and soil will be removed from around each well casing to attach a pressure fitting, and the casings will be pressurized at approximately 20 pounds per square inch(psi) for approximately five to ten minutes to allow for maximum displacement of grout from the well casing into the sand pack. The volume of neat cement injected will be recorded for each well and additional grout slurry will be added to the well casings as needed. Following the grouting procedure, each well will be over-drilled to approximately three feet below ground surface (bgs) and the PVC casing destroyed. Additional grout slurry will be placed into the over-drilled borings to within approximately one half to one foot below ground surface and existing surface conditions restored. A representative from the SJCEHD, if available, will verify that an adequate seal has been installed. The estimated volume of grout required for each monitoring well was calculated assuming complete over- drilling of monitoring wells MW-1, MW-2, MW-3, and MW-5 with 10-inch augers, over-drilling MW-4 with 12-inch augers, and pressure-grouting of MW-6 and MW-9. The estimated volume of grout required for monitoring wells MW-7 and MW-8 was calculated assuming complete over-drilling with 8-inch augers inside the 83/8-inch steel conductor casing which is set in cement to depths of 84 and 86 feet, respectively. The conductor casing will become part of the well destruction seal. The over-drilling using 8-inch augers through the 8 3/8-inch conductor casing will remove all well construction materials. The estimated volume of grout required for each well is shown in Table 1, below. Table 1: Estimated Grout Volumes Installation Destruction Estimated Casing Diameter Total Depth Grout Well I.D. Boring Diameter Boring Diameter (inches) (inches) (inches) (feet) Volume (gallons) MW-1 2 8 10 45 182 MW-2 2 8 10 45 182 MW-3 2 8 10 45 182 MW-4 4 10 12 49 285 MW-5 2 8 10 49 198 MW-6 2 8 Pressure Grout 49 30.3 MW-7 2 8 8 93 242 MW-8 2 8 8 93 244 MW-9 2 8 Pressure Grout 94 32.0 The soil cuttings, pieces of PVC casing, and any broken asphalt or concrete will be placed in DOT- approved 55-gallon drums, sealed, labeled, and left on-site pending laboratory analyses for characterization and disposal. Traffic boxes will be recycled or disposed of in the trash. Samples will be analyzed for total petroleum hydrocarbons quantified as gasoline (TPH-G) by EPA Method 8015M, for benzene, toluene, ethyl benzene, total xylenes (13TEX), and selected gasoline oxygenates/additives by EPA Method 826013, and for lead (soil only) by EPA Method 6060 or equivalent method. Gasoline i� CONDOR