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Working To Restore Nature <br /> as diesel (TPHD), and benzene, toluene, ethylbenzene, and total xylenes (BTEX) utilizing EPA <br /> methods 503018015/8020 <br /> ' Groundwater well purge and sample logs are provided in Appendix A. <br /> ' RESULTS OF LABORATORY ANALYSES <br /> Water samples collected from wells MW-1, MW-2, and MW-6 were analyzed for TPHG, <br /> ' TPHD, and BTEX using modified EPA methods 503018015/8020. These results and cumulative <br /> results of laboratory analyses are summarized in Table 1 The Chain of Custody Record and <br /> laboratory analytical reports are included in Appendix B <br /> C <br /> Results of this quarter's laboratory analyses of water samples from wells MW-1, MW-2, and <br /> MW-6 indicate the following <br /> • The concentrations of BTEX in wells MW-2 and MW-6 remained at nondetectable levels � <br /> (<0.5 ppb) since the last monitoring episode The concentrations of BTEX in well MW- <br /> ' 1 increased from nondetectable levels (<0 5 ppb) to 6 4 ppb, 22 ppb, 4 5 ppb, and 16 <br /> ppb, respectively <br /> I <br /> • In well MW-I, the concentration of TPHG increased from nondetectable (<50 ppb) to <br /> 130 ppb since the previous monitoring episode in September 1993 TPHD decreased <br /> ' from 250 ppb to 76 ppb. <br /> i <br /> • The concentration of TPHG in well MW-2 remained nondetectable (<50 ppb) TPHD <br /> decreased from 720 ppb to nondetectable (<50 ppb) <br /> I <br /> • The concentrations of TPHG and TPHD in downgradient well MW-6 continue to remain <br /> ' nondetectable (<50 ppb). <br /> CONCLUSIONS <br /> Based on the results of this quarterly monitoring and previous work performed at the site, <br /> RESNA concludes that the TPHG concentrations increased or remained the same, TPHD <br /> concentrations have decreased or remained the same, and BTEX concentrations in groundwater <br /> have increased or remained the same since the last monitoring episode in September 1993 The <br /> majority of gasoline hydrocarbons had been consistently detected in the vicinity directly <br /> downgradient from the former tank pit(in well MW-I) The concentrations detected in the wells <br /> sampled are consistent with historical patterns <br /> ' -UW561QUART1,YI4QMR1M FNL 3 <br />