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I ' Site Background Information: Fisco Warehouse ' Page 5 of 6 eight-hour test. The flow rate was measured between 25 standard cubic feet per minute ' (scfm) and 30 scfm for the eight-hour test. Organic vapor (OV) readings ranged from 108 mg/kg to 363 mg/kg. Induced vacuum measured at the extraction well (VW-2) ranged from 54 inches to 72 inches of water. ' The greatest vacuum was measured in the observation point nearest the extraction well g (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. On 31 July 2003, ground water monitoring well MW-8 was installed at the site to a depth of 95 feet bsg. Seven soil samples were submitted for laboratory analysis from pilot boring MW-8. THP-g, TPH-d,BTEX, and the five fuel additives were not detected at or above laboratory reporting limits in the soil samples submitted,nor were they detected at or above reporting limits in the first ground water sample collected from MW-8 in August 2003. SITE CONCEPTUAL MODEL Based on the data collected to date from soil borings and monitoring well installations, AGE has developed a site conceptual model for the release, migration and distribution of the contaminants in the subsurface as described below: The soil profile beneath the site is composed dominantly of sands and silts from surface grade to approximately 96 feet bsg,and finer-grained silts and clays from 96 feet bsg to total depth of 134 feet I bsg. Since initiation of ground water monitoring in February 2000,depth to ground water measurements I have fluctuated between a 33 feet btoc and 62 feet btoc. The inferred ground water flow direction generally has been towards the northwest (nine times) at gradients ranging between 0.001 ft/ft and . 0.008 ft/ft; ground water flow was towards the south four times at gradients between 0.01 ft/ft and Advanced GeoEnvironmental,Inc