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<br /> samples were obtained by EMC on May 17, 2001 and delivered in a chilled state, in an ice chest,
<br /> following strict Chain-of-Custody procedures to a state certified laboratory Well MW-11 was
<br /> resampled on May 24, 2001, because the original sample collected on May 17, 2001 was broken
<br /> during shipping These samples were analyzed for volatile aromatic compounds of benzene,toluene,
<br /> ethylbenzene, and xylenes(BTEX) and oxygenates (including MTBE) by EPA method 8260B, and
<br /> total petroleum hydrocarbons (TPH-g)by EPA method 8015M modified for gasoline Ethanol and
<br /> methanol were analyzed by EPA method D285 (Glycols-Alcohols)
<br /> TPH-g, BTEX, and MTBE concentrations appear in Table 1, while historical oxygenates and
<br /> alcohols results are presented in Table 2 Copies of laboratory reports and Chain-of-Custody
<br /> documents are included in Appendix B The TPH-g, benzene, and MTBE isoconcentration maps
<br /> are presented in Figures 2,3, and 4. The highest groundwater concentrations of TPH-g, benzene,
<br /> and MTBE were found in monitoring well MW-11 (239,000 ug/L, 55,800 ug/L, and 2,900 ug/L),
<br /> respectively
<br /> Since the third quarter of 1997,Thrifty has analyzed for the requested oxygenates di-isopropyl ether
<br /> (DIPE), ethyl-tert butyl ethyl (ETBE), tert-amyl methyl ether(TAME), and tert-butanol (TBA), and
<br /> MTBE by method 8260B The following alcohols were also requested for analysis ethanol and
<br /> methanol Laboratory results indicate no alcohols or oxygenates (besides MTBE) were detected,
<br /> with the exception of TBA in wells MW-10 (24 ug/L) and MW-11(818 ug/L)
<br /> Remediation Status
<br /> Vapor Extraction system
<br /> On April 12, 2001, a new Baker Furnace Thermal Oxidizer Unit was tested, and placed into
<br /> operation on April 26,2001 with the hour meter reading at zero Presently, the remediation system
<br /> is connected to soil vapor extraction well (VW-1, VW-2 (A,B), VW-3, VW-4 (A,B,C), VW-5
<br /> (A,B,C), and VW-6(A,B,C)) During this quarter the only wells operating were VW-2A, VW-213,
<br /> VW-3, VW-5C, and VW-613 During this reporting period, the soil vapor extraction unit (VEU)
<br /> operated approximately 1,344 hours during the Second Quarter 2001, and approximately 24,810
<br /> pounds of total petroleum hydrocarbons for gasoline (TPH-g) were removed (Table 3)
<br /> Advanced GeoEnvironmental, Inc (AGE) was retained by Thrifty to bring the remediation system
<br /> into operation, and their Soil Vapor/Groundwater Extraction Start-Up report is presented in
<br /> Appendix G AGE relinquished the system operations to Earth Management Company (EMC) on
<br /> June 26, 2001 Field Status Reports detailing system operation are shown in Appendix C
<br /> Effluent vapor samples were collected on April 12, May 10, May, 17,and June 21,2001 Additional
<br /> samples were collected on May 10 and May 17, 2001 from selected well heads, and from the
<br /> remediation system influent The well head, influent, and effluent vapor samples were analyzed for
<br /> TPH-g by EPA method 8015, and BTEX/MTBE by EPA method 8021B The initial influent and
<br /> effluent vapor samples were sent to McCampbell Analytical, Inc for analysis, and all subsequent
<br /> samples sent to Associated Laboratories for analysis A copy of the sample well-head vapor
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