Laserfiche WebLink
04 January 1999 <br /> AGE-NC Project No. 95-0100 <br /> Page 3 of 5 <br /> Hydrocarbon concentrations detected in subsequent influent soil gas/vapor samples were as follows: <br /> • 01 September 1998: TPH-g was detected at 870µg/l;toluene at 20 ug/l; ethylbenzene at 34 <br />' µg/1 and total xylenes at 200,ug/l. <br /> • 01 October 1998: TPH-g was detected at 820 µg/1; toluene at 13 µg/1; ethylbenzene at 39 <br />' µg/l and total xylenes at 200 4g/1. <br /> • 26 October 1998: TPH•g was detected at 610 µg11; toluene at 6.6 µg/1; ethylbenzene at 27 <br /> µg11 and total xylenes at 160µ.g/1. <br /> TPH-g was detected at 85µg/1 in the sample collected from the effluent stream on 01 October 1998. <br />' Additionally, BTEX were detected in the vapor sample collected from the effluent stream at a <br /> maximum concentration of 20 ppb (total xylenes). <br />' The analytical results are summarized on Table 1. The laboratory report (MAI Sample Numbers. <br /> 92931, 94427, 94479, 96247/96248 and 97731197732) Quality Assurance and Quality Control <br /> (QA/QC) reports'and chain-of-custody forms are included in Appendix A. <br /> No effluent soil gas/vapor sample was collected and analyzed in July 1998, due to a ruptured sample <br /> bag <br /> Hydrocarbon concentrations as measured from the effluent stream in August/September and October <br />' indicated a rate of destruction from 89.6 to a minimum of 96 percent. The rate of destruction for <br /> late July could not be calculated. <br />' The highest concentration of organic vapor measured with the OVM was 620 parts per million <br /> (ppm), measured during the August/September sampling event. Concentrations of extracted organic <br /> vapor measured with the OVM were low compared to the analytical results from soil gas/vapor <br /> ' samples. <br /> 3.2. MASS OF RECOVERED HYDROCARBONS <br /> The hydrocarbon mass (TPH-g) removed during the operating period was calculated using the <br /> t T -following-equation: Mf- C�Q•t -- _- <br /> where: M=cumulative mass recovered (kg) <br /> C= soil gas/vapor concentration(kg/m3) <br /> lot Q =extraction flow rate (m3/hr). <br /> t=opehailonal period, in hours <br /> Advanced GeoEnvironmental,Inc. <br />