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' 26 January 2007 AGE-NC Project No. 01-0839 Page 9 of 12 No additional constituents of concern were detected at or above laboratory detection limits in the ' vapor samples analyzed. Analytical results of soil vapor samples are summarized in Table 4. The laboratory report(CTEL Project No. CT214-0612230),QA/QC report,and chain of custody forms are included in Appendix G. ' 6.1.3. Results of the Shallow SVE Pilot Test The flow rate was measured between 80 standard cubic feet per minute (scfm)and 85 scfm for the ' 8-hour test. Influent organic vapor readings ranged from 303 parts per million (ppm) to 872 ppm. Induced vacuum measured at the extraction well (VW-2) was between 28 and 30 inches of water. As expected, the highest vacuum was measured in the shallow-screened observation point nearest ' the extraction well (VW-5).Vacuum measurements taken from the deep-screened extraction wells VW-1, VW-3, and VW-6 were erratic,ranging from 0 to 0.26 inches of water. The maximum vacuum measured at the observation points during the pilot test was plotted versus the distance from the extraction well (Appendix H). The theoretical radius of influence (ROI)was determined by drawing a best-fit line though these data points to correlate distance to vacuum data. ' At a vacuum of 0.10 inches of water, the ROI is approximately 62 feet; at a vacuum of 1.0 inches of water, the ROI is approximately 37 feet. Based on the United States Environmental Protection Agency (EPA)-prepared document, How to Evaluate Alternative Cleanup Technologies For UST Sites,the ROI 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 a vacuum of 0.1 inches of water,the extrapolated ROI at the site will be approximately 62 feet. Figure 3 depicts the ROI. ' 6.2. DEEP WELL SVE PILOT TEST On 27 December 2006,a 1-hour SVE pilot test was conducted at the site using deep-screened vapor ' well VW-1, screened from 45 feet to 60 feet bsg, as the extraction well. The test was conducted using the same SVE equipment used during the shallow pilot test on 26 December 2006. The flow rate was unable to be measured on the flow meter,which requires a flow rate greater than 4 scfm to register. Induced vacuum measured at the extraction well (VW-1) was approximately 64 inches of water. Wells VW-3 and VW-6 were subsequently tested with similar results and the ' pilot test was terminated after attempting to draw from all three deep-screened wells. No vapor samples were collected. Advanced GeoEnvironmental,Inc.