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FLUOR DANIEL GTI s were drilled out using a truck-mounted drill rig equipped with 8-to 10-inch-diameter hollow-stem augers Following removal of the well casings and sand annulus, each boring was grouted to within 6 inches of the surface with Portland cement The cement was pumped through tremie pipe installed to total depth of the boring to allow for proper settling of the grout Each boring location was topped with hot patch asphalt to match the existing grade On-site groundwater monitoring wells MW-7, MW-9, and PW-1, and off-site wells PW-2, MW-5, MW-8, MW-10, MW-11, MW-13, MW-14, MW-15A through MW-1513, MW-16, MW-18, and MW-19 were destroyed using pressure grouting techniques Portland cement was pumped through tremie pipe installed to total depth of the well Following grouting, 30 psi of air pressure was applied to the top of each casing to push the cement through the screened interval Air pressure was applied at 5 minute intervals and repeated three times to monitor the drop of grout inside the casing Following pressure grouting, the top 3 feet of well casing and annulus material in each boring was drilled out or excavated Additional cement was used to fill the resulting hole to approximately 6 inches below grade and topped with hot patch asphalt or native soil to match the existing grade Off-site well MW-12 was drilled out to total depth and grouted due to a submersible pump lodged In the well casing at approximately 23 feet below surface grade The two groundwater extraction wells RW-1 and PW-3, constructed of 12-inch- and 10-inch-diameter low grade carbon steel, respectively, were destroyed by perforating or ripping the well casing The casings were then grouted with Portland cement pumped through tremie pipe Hot patch asphalt and black-dye concrete was used at the surface to match existing grade Grouting of the borings was observed by Ms Mary Meays and Mr Harlin Knoll of the SJCPHS Field notes are included as Attachment 3 Waste Disposal All well-related materials, including well casings, well boxes vaults, and associated concrete were segregated from the well annulus material and the segregated materials were placed in two 20-yard bins located on site Approximately 15 cubic yards of soil was generated from the well destruction activities Two discrete soil samples were collected from the soil bin on November 7, 1996 The samples were collected in 6-inch brass sleeves sealed, labeled, and placed on ice in an insulated cooler for transport under proper chain-of-custody manifest to Western Environmental Science & Technology (WEST) in Davis, California for analysis The two samples were combined in the laboratory into one composite sample and analyzed for benzene toluene, ethylbenzene, and xylenes (BTEX), methyl-tert-butyl-ether (MTBE), and total petroleum hydrocarbons-as-gasoline (TPH-G) by EPA methods 8020/8015 total lead by EPA method 6010, and Waste Extraction Test (WET) for lead by EPA method 7421 The composite sample did not 023Dwdes 4rf5tN 5 11 t Summary of Well Destruction December 17 1996 The Southland Corporation 9110 Thornton Road Stockton CA 2