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' 17 May 2006 I . AGE-NC Project No 03-1071 ' Page 3 of 5 Analytical results of the gas/vapor samples are summarized in Table 2 The laboratory report(CTEL ' I D No 0604-084) and chain-of-custody forms are included in Appendix B, GeoTracker confirmation pages of the submitted laboratory electronic deliverable format(EDF)files are included in Appendix C ' 24 RESULTS OF SVE PILOT TEST On 12 April 2006,the SVE pilot test was operated at the site for approximately eight-hours(between 0900 and 1700) From the inlet of the SVE vacuum blower, the SVE flow rate was measured to be ' between 33 SCFM and 40 SCFM, the OV readings were consistently observed to be greater than 10,000 parts per million volume(ppmv), the induced SVE vacuum extracted from well VW-1 was ' a constant 60 inches of water, although the initial SVE vacuum measurement was observed at 68 inches of water SVE field measurements are summarized in Table 1 ' The vacuum-induced pressure reduction was monitored from surrounding observation points(VW-2, VW-3, VW-4, MW-1, MW-2 and MW-3) with air-tight well caps pre-connected with Magnehelic vacuum gauges fitted to each observation well As anticipated, the greatest induced vacuum was '• observed from adjacent well MW-3 (9 feet southwest of VW-1) at a measurement as high as 1 15 inches of water Significant induced vacuum was observed from wells VW-2(19 feet east-northeast of VW-1), VW-3 (21 feet south-southeast of VW-1), MW-1 (45 feet west of VW-1)and MW-2 (42 ' feet east of VW-1)at vacuum measurements ranging between 0 5 and 0 9 inches of water Moderate induced vacuum was observed from well VW-4 (42 feet north of VW-1) at measurements ranging ' between 0 15 and 0 2 inches of water The maximum vacuum measured at wells VW-1, VW-2,VW-3, VW-4, MW-1, MW-2 and MW-3 ' during the 8-hour SVE pilot test was plotted versus the distance from the extraction well The effective radius of influence was determined by drawing a best-fit line though these data points to correlate distance to vacuum data(Appendix B) At a vacuum potential of 0 10 inches of water,the ' radius of influence is approximately 42 feet, at an induced vacuum potential of 1 0 inches of water, the radius of influence is approximately 27 feet, at 10 0 inches of water, the radius of influence is approximately 9 feet 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 will be approximately 42 feet Figure 3 depicts the effective radius of influence at the site Advanced GeoEnvironmental,Inc