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I 17 January 2005 AGE-NC Project No 95-0103 Page 7 of 9 ' 3 2 2 Analytical Results of Ground Water Samples TPH-g was detected in the ground water samples from monitoring wells MW-3,MW-4,vapor wells VW-1,VE-1,VE-3 and VE-5 and air-sparging well VE-1/AS TPH-g was not detected In the ground water samples from monitoring wells MW-1, MW-2, MW-5, MW-6 or air-sparging well ASO-1 The highest concentration was detected in sample MW-4 at a concentration of 1,800 pg/l,however, ' the other impacted wells all contained TPH-g at concentrations above 1,000 µg/l BTEX compounds were detected only In well MW-4 at concentrations of 7 µg/I benzene, 2 4 µg/1 toluene, 27 µg11 ethylbenzene and 5 6 µg/1 total xylenes The fuel additive MTBE was detected in samples MW-4 and VE-1/AS at concentrations of 9 5µg11 and 9 5µg11, respectively No other target analytes were detected in the samples analyzed The analytical results of current and Lprevious monitoring well samples are summarized in Tables 2 and 3 The laboratory report of the current ground water sampling data(CTEL 0412157),quality assurance and quality control(QA/QC) lie data and chain-of-custody form are included in Appendix E 4.0. SUMMARY/CONCLUSIONS d monitoring activities AGE concludes the Based on the results of ground water remediationan g , following - Between December 2003 and December 2004, the ground water extraction and treatment system processed approximately 771,870 gallons ofwater The total volume of ground water treated as of 18 December 2004 is approximately 3,481,830 gallons TPH-g, BTEX compounds and MTBE were detected in influent samples and ground water ' extraction samples collected from wells EW-1,EW-2,EW-3 and VW-6 With the exception of extracted groundwater samples collected from well EW-1,dissolved TPH-g concentration trends show generally declining TPH-g concentrations In the extraction wells over the year 2004(Appendix C) Benzene concentrations in groundwater extraction samples also showed continued declining trends during the year 2004, although benzene concentrations in wells VW-6 and EW-1 appear to be at or approaching asymptotic values, at asymptote, declines ' in concentration over time will be very small (Appendix Q - MTBE has been detected sporadically in the ground water extraction wells since August ' 2003 In 2004, MTBE was detected once in EW-2, four times In VW-6 and five times in EW-3, at a maximum concentration of 130 µg/l (EW-3) The 2004 MTBE concentrations ' Advanced GeoEnvnron mental,Inc