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27 January 2006 <br /> AGE-NC Project No 98-0500 <br /> Page 4 of 10 <br /> Hydrocarbon concentrations detected in influent soil-vapor samples were as follows <br /> • 10 October 2005 TPH-g was detected at 320 micrograms per liter(µg/1),benzene at 19µg/l, <br /> toluene at 46 pg/l, ethylbenzene at 4 9 µg/1, and total xylenes at 28 µg/l <br /> • 25 November 2005 TPH-g was detected at 900 l.tg/l,benzene at 2 7 pg/l,toluene at 17 µg/l, <br /> ethylbenzene at 4 8 pg/l, and total xylenes at 27 pg/l <br /> • 28 December 2005 TPH-g, MTBE, and BTEX compounds were non-detect <br /> The hydrocarbon concentrations measured in influent stream samples during the fourth quarter 2005 <br /> increased in November and decreased at the later portion of the quarter Hydrocarbon concentrations <br /> measured In samples from the effluent stream in fourth quarter 2005 indicated a greater than <br /> 98 percent rate of destruction, indicating that the destruction efficiency of the SVE unit was <br /> acceptable over the remediation period Influent and effluent soil-vapor sample analytical results are <br /> summarized in Table 2 The laboratory reports(CTEL Project Nos CT214-0510054,-0511175,and <br /> -0512213) quality assurance/quality control (QA/QC) reports, and chain of custody forms are <br /> included in Appendix B <br /> 23 MASS OF RECOVERED HYDROCARBONS <br /> The mass of TPH-g removed during the operating period was calculated using the following <br /> equation M = C•Q-t <br /> where M = cumulative mass recovered (kg) <br /> C = soil-vapor concentration (kg/m3) <br /> Q = extraction flow rate (M3/hr) <br /> t= operational period, in hours <br /> The mass of hydrocarbons removed was based on analysis of soil-vapor samples The mass of <br /> extracted hydrocarbons was calculated using average hydrocarbon concentrations of influent soil- <br /> vapor sample data and average air flow rates A total mass of 1,176 pounds (lbs) of TPH-g, <br /> equivalent to a total volume of 188 gallons of TPH-g,were removed between 12 September and 28 <br /> December 2005 The volume-mass calculations and SVE unit performance table are provided in <br /> Appendix C <br /> 3.0. QUARTERLY WELL MONITORING PROCEDURES AND RESULTS <br /> . The quarterly ground water monitoring event was performed on 07 through 09 December 2005 <br /> Advanced GeoEnviroamcntal,Inc <br />