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1.1 V 19 October 2012 AGE-NC Project No. 97-0312 Page 16 of 22 • TPH-d in accordance with NIOSH 1550 for total extractable petroleum hydrocarbons. 6.2. RESULTS OF EIGHT-HOUR HVSVE PILOT TEST The HVSVE pilot test operated at the site for approximately eight-hours. Initially the HVSVE operated at normal conditions at approximately 10 inches of mercury. However, following approximately 30 minutes of high vacuum extraction, the catalytic oxidizer began a endothermic reaction; which resulted in over heating from the fuel within the soil vapor giving off greater heat than could be dissipated through advective flow of soil vapor. From the location of well VW-1, prior to the inlet of the HVSVE unit, the flow rate was measured to be between 86 SCFM at the start of the test when 10 inches of mercury was applied to nearly 35 SCFM when the HVSVE equilibrated at a vacuum of 5 inches of mercury. The average flow rate over the pilot test was 45 SCFM, however, the maximum flow rate would have been maintained if not for the over heating of the catalytic oxidation chamber and cell. The greatest OVM readings ranged from 1,700 to 2,300 parts per parts per million volume (ppmv). The induced vacuum extracted vapor from well VW-1 over 100 inches of water (IOW) during operation. From the surrounding observation wells, the greatest induced vacuum measurement was observed at vapor extraction well VW-2 (located 40 feet west of VW-1) at 1.15 IOW and an induced vacuum was generally observed in well VW-3 (located 30 feet east of VW-1), at measurements as high as 0.9 IOW. The maximum vacuum measured at wells VW-2,VW-3 during the 8-hour HVSVE pilot test was plotted versus the distance from the extraction well. The effective radius of influence was determined by generating a linear best-fit line through the shallow soil vapor well data points to correlate distance to vacuum data. Based on the United States Environmental Protection Agency (EPA)-prepared document, How to Evaluate Alternative Cleanup Technologies For UST sites the radius of influence is considered to be the distance from the extraction well at which a vacuum of at least 0.1 inches of water is observed. Based upon an effective vacuum potential of 0.1 inches of water, the calculated effective radius of influence at the site is approximately 50 feet. Based on the fine grained soil type at the site, a conservative soil vapor remediation radius was anticipated. Advanced GeoEnvironlnentnl,Inc. �1