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12 July 2012 <br />AGE-NC Project No. 02-0926 <br />Page 4 of 7 <br />4.1. SOIL VAPOR EXTRACTION PERFORMANCE <br />Between 16 March and 16 May 2012, the SVE remediation system was operational for a <br />total of 1,349 hours. During this operational period, SVE inlet flow rates (total flow) were <br />generally observed between 82 SCFM and 91 SCFM. Utilizing a photo ionization meter <br />(PID), hydrocarbon concentrations were measured from the SVE influent at concentrations <br />ranging 23 parts per million volume (ppmv) to 219 ppmv. Field measurements are <br />summarized in Table 2. <br />4.2. ANALYTICAL RESULTS OF VAPOR SAMPLES <br />A total of three influent and four effluent soil vapor samples were collected during the pilot <br />test to evaluate the effects of pilot sparging on the influent vapor stream of the on-site SVE <br />system. TPH-g were detected in all three influent samples at concentrations of 7,200 <br />micrograms per liter (pg/I), 1,100 pg/I and 900 pg/I, respectively (Table 4). All four BTEX <br />constituents were reported in influent vapor samples at maximum concentrations of 7.6 pg/I <br />benzene, 15 pg/I toluene, 3.5 pg/I ethylbenzene, and 48 pg/I total xylenes (Table 4). <br />TPH-g were detected in one of the four effluent samples at a concentration of 450 pg/I <br />(Table 4). All four BTEX constituents were reported in the effluent sample at concentrations <br />of 23 pg/I benzene, 10 pg/I toluene, 1.2 pg/I ethylbenzene and 6.7 pg/I total xylenes <br />(Table 4). Sample concentrations reported in the effluent vapor stream were due to the <br />carbon reaching its maximum treatment capabilities. The spent carbon was removed and <br />replaced as described in section 2.0. All other effluent samples collected were non-detect <br />for hydrocarbon constituents. <br />Analytical results of soil vapor samples are summarized in Table 4. The laboratory reports <br />(CTEL Project Nos., 1203119, 1204063, 1204093 and 1205122), QA/QC reports, and <br />chain of custody forms are included in Appendix D. Laboratory EDF files were uploaded <br />to the State GeoTracker database under confirmation number 8026383399, 6034916698, <br />4389905571 and 5207563042. <br />4.3. MASS/VOLUME CALCULATIONS OF RECOVERED PETROLEUM <br />HYDROCARBON VAPOR <br />The hydrocarbon mass removed during the SVE operating period was calculated using the <br />equation: M = C-Q-t <br />where, M = cumulative mass recovered (kg) <br />Advanced GeoEnvironmental, Inc.