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Overdrilled Wells: • MW-3 (screened 8-28 ft bgs) 10.5 bags of cement and 60 gallons of water • MW-4 (screened 5-25 ft bgs) 12 bags of cement and 69 gallons of water • MW-7 (screened 30-35 ft bgs) 15 bags off cement and 86 gallons of water For wells that were pressure grouted, only two wells existed in unpaved areas (MW-5 and MW-6, off-site within City of Stockton right-of-way along the north side of Harbor Street). The covers and cement pads were completely removed and all locations had the 2" PVC cut below grade. Wells on-site, in paved areas (MW-1, MW-10, MW-11, and MW-12) had the cover and interior box removed, maintaining only the outer ring to limit the disturbance to the surrounding paved area. Once completely sealed, the rings were cemented flush with the surrounding paved area. All wells that were pressure grouted followed the same mix ratio as stated above and consistent with the EHD approved workplan procedures, the sealing material was pumped via tremie pipe to the bottom of each well location. Once sealing material was at the ground surface, the wells were pressurized with 25 psi for a period of 5 minutes. Additional sealing material was placed to top off and/or periods of pressurization were conducted until the wells were sealed to the surface and pressurization no longer caused the material to settle as documented below: Pressure Grout Wells: • MW-1 (screened 8-28 ft bgs): one pressurization, negligible settling, 17 gal. used • MW-2R (screened 8-28 ft bgs): one pressurization, minor settling, 20 gal. used • MW-5 (screened 5-25 ft bgs): one pressurization, minor settling, 20 gal. used • MW-6 (screened 5-25 ft bgs): two pressurizations, minor settling, 21 gal. used • MW-10 (screened 5-25 ft bgs): three pressurizations, significant settling, 40 gal. used • MW-11 (screened 8-28 ft bgs): one pressurization, negligible settling, 17 gal. used • MW-12 (screened 30-35 ft bgs): one pressurization, minor settling, 20 gal. used The finalized permit forms (DWR 188) and associated boring/well logs are included for your review. FINAL DISPOSITION OF INVESTIGATIVE DERIVED WASTE Upon arrival on site, H&H determined that two (2) drums of soil and one (1) drum of soil and grout from the previous project in 2008 still existed on site, obstructed by equipment owned by Penny Newman Grain. These solids were disposed along with the newly derived waste from the abandonment project including three (3) drums containing over- drill cuttings from MW-3, MW-4, and MW-7; one (1) drum of concrete/manhole covers from abandoned wells MW-3, MW-4, MW-5, and MW-7; and one (1) drum of sludge remaining in empty purge water drums that was consolidated and disposed. Therefore, a total of eight (8) drums of solid waste totaling 2.79 tons were hauled by Advanced Chemical Transport on March 3, 2010 and disposed at the Forward Landfill in Manteca, CA under waste acceptance #9462 dated March 9, 2010, R:IC0NTGRAN\Stockton1We11 Closure 20091Post Abandon and Disposal Letter.doc