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1 QUARTERLY GROUNDWATER SAMPLING As part of the groundwater monitoring program, groundwater samples were obtained from monitoring wells MW-2, MW-3R, MW-4, MW-5, MW-6, TB-1, TB-7, TB-8, TB-10, and vapor monitoring wells which contain groundwater (TB-9, TB-11, and TB-12) Groundwater samples ' were obtained by EMC and delivered in a chilled state in an ice chest following strict Chain-of- Custody procedures to a state certified laboratory and analyzed for total petroleum hydrocarbons as gasoline (TPH-g) by EPA method 8015 modified, and for volatile aromatic compounds of ' benzene, toluene, ethylbenzene, and xylenes, by EPA method 8020 TPH, Benzene, and MTBE concentrations are plotted and contoured in Figures 2 through 4, respectively ' Starting in the third quarter of 1997, as required by the Central Valley Regional Water Quality Control Board (CVRWQCB), samples were analyzed for Oxygenates by EPA Method 8260 The ' seven oxygenates which were sampled for are Di-isopropyl ether, Ethanol, Ethyl tert-Butyl Ether, Methanol, Methyl tert-Butyl Ether(MTBE), Tert-Amyl Methyl Ether, Tert-Butanol A summary of select analytical sampling results are provided in Table 1, and a copy of the laboratory analytical report is contained in Appendix A On March 22, 1999, Thrifty Oil Co retained Kjeldsen, Sinnock, and Neudeck (KSN) Consulting ' Engineers and Land Surveyors to survey the locations and elevations of wellheads/Top of Casings of groundwater monitoring wells A copy of the surveying data is presented in Appendix C Thrifty is in the process of contracting with Pacific Gas and Electric Company for temporary gas service to the remediation compound CONCLUSION ' During the 1 st Quarter 1999, TPH-g concentrations in the site monitoring wells were in the range of non-detectable(<50 ug/L)to 13,000 ug/L(MW-5) Benzene concentrations in the site monitoring wells were in the range of non-detectable (<0 3 ug/L) to 4 9 ug/L (TB-12), and MTBE concentrations in the site monitoring wells were in the range of non-detectable (<20 ug/L) to 13,000 ug/L (MW-5) ' Thrifty plans to continue the current groundwater monitoring and sampling program, and had the site surveyed on March 22, 1999 ' On March 29, 1999, a letter was sent to Mr Mike lnfurna, Jr from Mr Jeff Suryakusuma of Thnfty Oil Co (Thrifty) The contents of the letter was the summary of site inspection held on March 17, ' 1999 Mr lnfurna, Jr was verbally informed by Mr Suryakusuma on April 20, 1999 via telephone that the work has been completed and in awaiting inspection A copy of the letter is included in ' Appendix D Thrifty has submitted to the San Joaquin Air Pollution Control District (SJAPCD) a permit application to operate a remediation system at this site On December 23, 1998 the SJAPCD