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Benzene and fuel additives were not detected at or above laboratory reporting limits In any of the ground water samples ' 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 cfu/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, nitrates (NO3), phosphate (POO 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% ' On 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 1 TPH-g was detected in the soil gas/vapor samples(vapor samples)at concentrations ranging from 1,300 µg11 to 2,700 ug/1 Toluene, ethylbenzene and total xylenes were detected In the ' gas/vapor samples at concentrations as high as 47 p.g/l toluene,30 µg/1 ethylbenzene and 220 pg/l 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 scfrn for the lie 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 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 The effective radius of influence was determined by drawing a best-fit line though these data points to ' correlate 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 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 47 feet ' Advanced GeoEnvironmental,Inc