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1 Report on Additional Site Assessment and Soil Vapor Extraction Test 2 7-Eleven Store No 17334,4501 North Pershing Avenue Stockton GA August 21 2002 ' The highest dissolved benzene, TPH-G, and MTBE concentrations in grab groundwater samples collected February 20, 1997, were reported in sample GP-4 at 9,100 micrograms per liter(µg/L), 150,000 µglL, and 84,000 µg/L, respectively From September 23 through November 26, 1997, Fluor Daniel GTI supervised the drilling of five ' groundwater monitoring wells (MW-1, MW-1A, MW-2, MW-3, and MW-4) to depths ranging from 35 to 40 feet bg (Figure 2) Soil samples were collected during drilling at 5-foot-depth intervals from 5 feet bg to total depth In addition, the areas of well MW-1 and MW-2 were sampled continuously from 15 feet bg ' to total depth A total of twenty-three soil samples collected from the soil borings were submitted for laboratory analysis The groundwater monitoring wells were constructed of 2-inch-diameter, Schedule 40 poly-vinyl-chloride (PVC) casing with flush threads, and 0 020-inch-slat well screen Wells MW-1, MW-2, ' MW-3, and MW-4 are screened from 13 to 33 feet bg, and well MW-1A is screened from 38 to 40 feet bg On August 14, 1998, monitoring wells MW-1 and MW-1A were abandoned, as they were located adjacent ' to the USTs (removed on August 25, 1998) New USTs were installed in an area separate from the former UST area On August 25, 1998, approximately 200 cubic yards of soil were excavated from the new tank pit to accommodate the installation of two new double-wall steel 10,000-gallon USTs A total of four soil samples were collected from the new UST excavation Soil samples NTP-W-14' and NTP-E-14' were collected at a depth of 14 feet bg from the floor of the excavation Samples SW-E-6' and SW-N-6' were collected from the side wall of the northeast corner of the new tank pit excavation On July 17, 1998, Fluor Daniel GTI personnel collected six soil samples from the floor of the UST excavation, from beneath each end of the three USTs at a depth of approximately 14 feet bg On December 17, 1998, double-nested groundwater monitoring well MW-5 was installed to a depth of 40 5 feet bg Each well nest is constructed of 2-inch-diameter Schedule 40 PVC casings with flush ' threads and 0 020-inch-slot well screen The deep well nest (MW-5B) is screened from 38 to 40 feet bg The shallow well nest (MW-5A) is screened from 13 to 33 feet bg Additional well installation was required by the SJCPHS to further characterize the lateral extent of dissolved hydrocarbons and oxygenates SVE testing was conducted to evaluate the site for potential remediation if required by the SJCPHS t30 ADDITIONAL SOIL AND GROUNDWATER ASSESSMENT 31 Permitting/Site-Specific Health and Safety Plan ' Permits were obtained from the SJCPHS The existing site-specific Health and Safety Plan (as required by the Occupational Safety and Health Administration Standard Hazardous Waste Operations and Emergency Response guidelines 29 Code of Federal Regulations 1910 120)was used during recent ' activities The document was reviewed and signed by all company personnel and subcontractors prior to commencement of work at the site I 17334sardoc