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Well Destruction Workplan ATC Jamar Service Station Page 2 of 5 GHH's Second Quarter 2003 Groundwater Monitoring Report and Additional Assessment Report, dated June 2003. In January 2004,ATC Associates supervised the installation of five injection wells (IW1 through IW5) on-site. Each injection well was completed with a shallow and deep sparge point. The shallow spargepoints were installed to a depth of approximately 74 feet bgs and the deep spargepoints were installed to a depth of approximately 108 feet bgs. These wells were installed to facilitate remediation activities. From February 17 to April 20, 2004, ATC supervised the installation of groundwater monitoring wells MW6C, MW7C, MW8, MW9A, MW913, MW9C, MW10A, MW10B, and MW10C. These wells were installed to evaluate the groundwater quality both laterally and vertically downgradient from the site. In June 2004, operation of the ozone injection system at the site was initiated.The ozone remediation system consists of a KVA C-SpargeTM System Series 5030 model that has a maximum Os delivery rate of 4 grams per hour and injection rates of between 2.0 and 3.0 standard cubic feet per minute (SCFM). Between May 28 and 30, 2008, ATC supervised the installation of vapor extraction wells VEW1, VEW2, and VEW3 to depths of approximately 50 feet bgs. These wells were installed to facilitate remediation pilot testing activities and evaluate soil vapor extraction as an alternative remedial approach. During July 2008, one long term and two short term vapor extraction tests (VETs) were conducted at the site in an effort to evaluate the feasibility of soil vapor extraction (SVE) as a remedial option at the site. During the long term VET a vacuum was applied to VEW1 for approximately eight hours. During the first short term VET a vacuum was applied to VEW2 for approximately four hours. A vacuum was applied to VEW3 for approximately four hours during the second short term VET. The May 2008 subsurface investigation activities and July 2008 pilot testing were completed in general accordance with ATC's Subsurface Investigation and Pilot Test Workplan for Jamar Service Station, 4075 East Main Street, Stockton, California, dated January 15, 2008. This work was approved by the San Joaquin County Environmental Health Department(SJCEHD) in a letter dated January 18, 2008. A sensitive receptor survey was conducted for the site and surrounding area during August 2008 as reported in ATC's Sensitive Receptor Survey Report for Jamar Service Station, 4075 East Main Street, Stockton. In February 2009, ATC submitted the Supplemental Subsurface Investigation Work Plan dated February 27, 2009.This workplan proposed the advancement of one CPT boring with accompanying hydropunch borings to collect discrete grab groundwater samples below the "C" zone on site, and the installation of two deep, discretely screened groundwater wells to monitor the lateral extent of the groundwater contamination reported in the "C" zone grab groundwater samples collected from previous CPT borings. In March 2009, ATC submitted Interim Remediation Implementation Work Plan dated March 5, 2009. This workplan proposed the installation of one shallow groundwater monitoring well to define the shallow plume to the north, installation of two additional ozone infusion points and connecting them to the ozone remediation system (piping is already installed), trenching and piping to connect the SVE wells on site to the remedial compound, and initiation of interim soil remediation by SVE.