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GeoHydrologic Consultants, Inc. In September 2007,Thrifty obtained the UST removal permit to remove the three 12,000- gallon USTs, associated piping, and other appurtenances from the Site. Tafoya also obtained a Stockton Fire Department Permit and Special Inspection Permit in early December 2007 for removal of the USTs. A copy of the approved permits and associated information are included in Appendix B. In early December 2007,Tafoya and Associates of Chino, California performed the UST removal activities on behalf of Thrifty which consisted of disconnecting and capping the existing remediation system piping at affected wells,concrete removal,overburden soil excavation via backhoe, stockpiling of soil with cover in preparation for UST removal, and removal of the three fuel dispensers for future re-use. Volatile organic compound (VOC)emissions were monitored by GHC using a calibrated hand held Mini-Rae photo- ionization detector(PID)during soil excavation activities.No elevated VOCs readings were detected above background levels and no noticeable hydrocarbon odors were detected during the entire UST soil excavation process. Soils were stockpiled on plastic sheeting and covered with plastic sheeting awaiting soil analytical results from soil samples collected from each stockpile. The stockpile locations are depicted in Figure 3. On December 10,2007,the tank headspace was inspected and analyzed by Henry M. Sorensen, marine chemist,with an organic vapor analyzer and determined to be clean and safe for transport and recycling. A copy of the Hazardous Waste Tank Closure Certifications are included in Appendix B. On December 11,2007,the tanks were removed by crane and the associated fuel piping was removed and chopped up with a chop-saw into approximately 2 to 3 foot long pieces. The piping was placed into the empty tanks and the tanks and associated piping were loaded onto a flat bed truck with a crane, marked for transport,and taken to Vasco Road Landfill in Livermore, California for destruction. A copy of the certificate of destruction is included in Appendix C. Health Inspector Ray Von Flue and Michael Infurna, of the SJCEHD, were present onsite during the tank removal process and approved the tanks for offsite transport and disposal. The USTs extended to a depth of approximately 15 feet bgs and the UST tank pit which was filled with pea gravel extended beneath the USTs to a depth of 18.5 to 19 feet bgs. Due to caving sidewalls of pea gravel and the depth to the bottom of the UST excavation of approximately 18.5 to 19 feet bgs(approximately 3 to 4 feet beneath the bottom of the tanks), it was not safe or possible to collect undisturbed soil samples from the bottom of the tank pit via backhoe, therefore Mr. Infurna indicated that they would need to be collected at a later date via soil borings to a depth of approximately two feet below the bottom of the UST excavation in native soil at a depth of approximately 20 to 22 feet bgs. After receiving the soil analytical results from the stockpiles soil on December 12, 2007, which indicated that all of the stockpiled overburden was clean,the stockpiled soils were uncovered and placed into the UST excavation in 2 foot lifts and compacted to 95% relative density. In addition,the balance of the excavation was backfilled with clean imported%-inch crushed rock with an average bulk density of 103 pounds per cubic foot until flush with the edges of the surrounding pavement. This material was placed in the excavation the following week in two foot lifts and compacted to 95%relative density. The soil density for the backfilled excavation and trenches was tested at final TOC 172 UST Removal Report Final Page 9