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(TAME), and Tert-Butanol (TBA)) using EPA method 8260B Ethanol and methanol were also
<br /> analyzed by ASTM method D285
<br /> A summary of historical analytical sampling results for TPH-g, BTEX, and MTBE is provided in
<br /> Table 1, and oxygenate/alcohol results are summarized in Table 2 Copies of the EMC Field Status
<br /> Reports are presented in Appendix A, and copies of the laboratory analytical reports are contained
<br /> in Appendix B
<br /> The TPH-g, benzene, and MTBE isoconcentration maps are presented as Figures 2, 3, and 4,
<br /> respectively The analytical laboratory results indicate that the highest groundwater concentrations
<br /> of TPH-g, benzene, and MTBE were found in morutoring well MW-5 (59,000 ug/L, 5,250 ug/L, and
<br /> 33,700 ug/L, respectively) The selected oxygenate concentrations were below laboratory detection
<br /> limits, except for DIPE and TBA The DIPE concentration was 13 ug/L, (well TB-8) and the TBA
<br /> concentration was 7,240 ug/L (well MW-5)
<br /> Concentrations of methanol and ethanol were not detected above laboratory detection limits in any
<br /> of the wells sampled this quarter It has been over one year without detecting these analytes in the
<br /> groundwater samples Therefore, Thrifty respectfully requests for cessation of the requirement for
<br /> methanol and ethanol analysis at this site
<br /> Remediation Status
<br /> On July 1, 1999, a Baker Furnace Thermal Oxidizer Unit was placed into operation, to destroy
<br /> vapors extracted by the SVE system Presently, the remediation system is connected to SVE wells
<br /> MW-2, MW-4, MW-5, TB-3, TB-4, TB-6, TB-7, TB-9 (A, B), TB-II (A, B), and TB-12 (A, B) A
<br /> map presenting the extraction well layout is shown as Figure 5 At the beginning of the quarter the
<br /> only wells operating were TB-7 and MW-5 Subsequently, wells, TB-3 and TB-11 were also
<br /> included into the operation at 50% extraction on March 4, 2003, and on March 11, 2003 well TB-7
<br /> was shut down
<br /> During this reporting period, the soil vapor extraction unit (VELI) operated approximately 1,670
<br /> hours and approximately 40,510 pounds of TPH-g were removed this quarter as of March 18, 2003
<br /> (Table 3 and Appendix C) The cumulative system total as of March 18, 2003 is approximately
<br /> 21,024 hours of operation, and approximately 128,048 pounds of TPH-g removed The system
<br /> operated throughout the quarter
<br /> Vapor samples were collected from the system inlet and outlet ports on January 7 and March 12,
<br /> 2003, from the inlet and MW-5 on January 30, 2003, and also from selected site wells on February
<br /> 11, 2002 The samples were analyzed for TPH-g by EPA method 8015M for gasoline, BTEX, and
<br /> MTBE by EPA method 8021 B The effluent vapor laboratory results for March 12, 2003 indicated
<br /> that TPH-g concentration was 13 ppmV The effluent vapor laboratory results indicate benzene
<br /> concentrations were 0 08 ppmV for both the January 7 and March 12, 2003 events The effluent air
<br /> sample results are within the San Joaquin Valley Air Pollution Control District requirements
<br />
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