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<br /> Ethyl tert-Butyl Ether(ETBE), Methyl tert-Butyl Ether(MTBE), Tert-Amyl Methyl Ether
<br /> (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 TPHg,BTEX, and MTBE is provided in
<br /> Table 1, and oxygenate/alcohol results are summarized in Table 2 Copies of the EMC Field
<br /> Status Reports are presented in Appendix A, and copies of the laboratory analytical reports are
<br /> contained in Appendix B
<br /> TPHg,benzene, and MTBE isoconcentration maps are presented as Figures 2, 3, and 4,
<br /> respectively The analytical laboratory results indicate that the highest groundwater
<br /> concentrations of TPHg and MTBE were found in monitoring well MW-5 (23,400 ug/L and
<br /> 17,000 ug/L, respectively) The highest benzene concentration (1,770 ug/L)was detected in well
<br /> TB-7 The selected oxygenate concentrations were below laboratory detection limits, except for
<br /> DIPE in well TB-8 (1 0 ug/L) and TAME and TBA in well MW-5 (31 ug/L and 1,529 ug/L,
<br /> respectively) The method detection limits were elevated for DIPS, ETBE, TAME, and TBA in
<br /> well TB-7
<br /> Concentrations of methanol and ethanol were not detected above laboratory detection limits in
<br /> any of the wells sampled this quarter It has been over one year without detecting these analytes
<br /> in the groundwater samples Therefore, Thrifty respectfully repeats its request for cessation of
<br /> the requirement for methanol and ethanol analyses 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
<br /> wells MW-2, MW-4, MW-5, TB-3, TB-4, TB-6, TB-7, TB-9 (A, B), TB-11 (A, B), and TB-12
<br /> (A, B) A map presenting the extraction well layout is shown as Figure 5 The only wells
<br /> operating this quarter were TB-11 wtr, MW-5, and TB-3
<br /> During this reporting period, the soil vapor extraction unit operated approximately 2,037 hours
<br /> and approximately 1,040 pounds of hydrocarbon as TPHg were removed this quarter as of
<br /> September 23, 2003 (Table 3) The cumulative system total as of September 23, 2003, is
<br /> approximately 224,673 hours of operation, and approximately 130,629 pounds of hydrocarbon as
<br /> TPHg removed The system operated throughout the quarter except when it was shut down for
<br /> quarterly water sampling from August 7 though August 13, 2003 Field records of the SVE
<br /> system are provided in Appendix C
<br /> Vapor samples were collected from the system inlet and outlet ports on July 16, August 5, and
<br /> September 9, 2003 The samples were analyzed for TPHg by EPA Method 8015M for gasoline,
<br /> BTEX, and MTBE by EPA Method 8021B
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