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GeoHydrolagic Consultants Inc Michael Infurna of SJCEHD was present onsite during all well abandonment activities along with GHC staff. Existing well MW-12 was abandoned by over drilling on December 1, 2007, by Test America Drilling with a guide rod to make sure that the auger stayed true to the original borehole and the well was completely removed. MW-12 was overdrilled through the existing 12-inch diameter steel conductor casing using an 8.5-inch diameter O.D. hollow stem auger to total depth of 74 feet. The well was then filled with bentonite grout from the bottom of the borehole upward via 1-inch diameter tremie pipe.A total of 150 gallons of bentonite grout were placed in the borehole and topped with 4 bags of bentonite chips to a depth of approximately 16 feet below grade,which was up inside the steel conductor which was later removed during UST removal activities. Existing dual-nested well M W-11NW-3.was abandoned by over drilling on December 1, 2007, by Test America Drilling Co. with a guide rod to make sure that the auger stayed true to the original borehole and the well was completely removed. This well overdrilled through the existing 12-inch diameter steel conductor casing using a 10.5-inch diameter auger; however,the auger hooked on the steel conductor and was therefore switched out to an 8.5-inch diameter O.D. hollow stem auger in order to get through the conductor and the well was drilled out to a total depth of 61 feet.The well was then filled with bentonite grout from the bottom of the borehole upward via 1-inch diameter tremie pipe.A total of 150 gallons of bentonite grout were placed in the borehole and topped with 6 bags of bentonite chips to a depth of approximately 10 feet below grade, which was up inside the steel conductor which was later removed during UST removal activities. Existing dual-nested well VW-2 s,d was abandoned by over drilling on December 2, 2007, by Test America Drilling Co. with a guide rod to make sure that the auger stayed true to the original borehole and the well was completely removed. The well was overdrilled through the existing 12-inch diameter steel conductor casing using an 10.5- inch diameter O.D. hollow stem auger to total depth of 42 feet.The well was then filled with bentonite grout from the bottom of the borehole upward via 1-inch diameter tremie pipe.A total of 200 gallons of bentonite grout were placed in the borehole to a depth of approximately 5 feet below grade,which was up inside the steel conductor which was later removed during UST removal activities. 3.3 UST Removal Activities In September 2006,the contents of the UST were removed,the tanks and piping were triple rinsed,and appropriate measures were completed for in-place temporary closure of the three 12,000-gallon USTs and associated equipment.The liquid waste,approximately 900 gallons of rinsate, was transported by Asbury Environmental Services to DeMenno/Kerdoon of Compton, California where it was recycled. Copies of the waste manifest and recycling certificate are included in Appendix B.As noted on the SJCEHD Underground Storage Tank Disposition Tracking Record, on September 13,2006,the three 12,000 gallon USTs were decontaminated as a part of the temporary closure procedure(Appendix B). TOC 172 UST Removal Report Final Page 8