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r I ' The general count of heterotrophic organisms in soil sample CPT1-31 was 12 2 X 105 ' (colony-forming units/gram) cfu/g and the selective count was 2 1 X 105 efu/g, which indicate a moderate population of organisms capable of gasoline metabolism However,the nutrient concentrations are at moderate to high levels to sustain ongoing bioremediation, I nitrates (NOA phosphate (PO4) and ammonium (NH4) were detected in the sample at � concentrations of 57 2,parts per million (ppm), 22 ppm and 28 38 ppm, respectively, indicating The moisture content (MC) of the soil sample was 23% IOn 14 January 2002, an 8-hour SVE pilot test was conducted at the site using vapor well VW-2, screened from 15 feet below surface grade(bsg)to 35 feet bsg as the extraction well The pilot test was performed to provide SVE data prior to installation of a full scale remediation system TPH-g was detected in the soil gas/vapor samples(vapor samples)at concentrations ranging from 1,300 gg/l to 2,700 4g/1 Toluene,ethylbenzene and total xylenes were detected in the gas/vapor samples at concentrations as high as 47 4g/l toluene,30µg/1 ethylbenzene and 220 µg/1 total xylenes Benzene and MTBE were not detected at or above laboratory reporting limits in the gas/vapor samples The SVE unit was operated at approximately 2,300 RPMs for the eight-hour test The flow rate was measured between 25 cfm (standard cubic feet per minute) and 30 scfm for the eight-hour test OV readings ranged from 108 to 363 ppm Induced vacuum measured at the extraction well (VW-2) ranged from 54 to 72 inches of water l • As expected, the greatest vacuum was measured in the observation point nearest the extraction well(VW-1) The lowest vacuum was measured in MW-6,approximately 66 feet north of the extraction point The maximum vacuum measured at the observation points during the pilot test was plotted versus the distance from the extraction well Th- effectiv.; radius of influence was determined by drawing a best-fit line though these data points to fcorrelate distance to vacuum data At a vacuum potential of 0 10 Inches of water,the radius of Influence is approximately 47 feet, at an induced vacuum potential of 1 0 inches of water, the radius of Influence Is approximately 30 feet, at 10 0 inches of water the radius of influence is approximately 13 feet Based on the United States Environmental Protection Agency(EPA)-prepared document,How toEvaluateAlternative Cleanup Technologies For I USTsrtes 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 in of water, the calculated effective radius of influence at the site will be approximat y 47 feet I Advanced GeoEnvirennnental,Inc I