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V 28 December 1999 AGE-NC Project No. 97-0351 Page 3 of 7 with the West UST area appeared to be of limited lateral extent. TPH-g was detected in four of ten grab ground water samples collected from the West UST area at concentrations ranging-from 84 to 44,000 4g/1 (micrograms per liter or parts per billion: ppb). Various BTE&X compounds were detected in six of tensamples analyzed at concentrations ranging from 0.60 to 7,800 ppb. Total petroleum hydrocarbons as diesel(TPH-d)was detected at concentrations up to 6,600 ppb from four of five grab ground water samples analyzed from the western property boundary. The subject property has no documented use of TPH-d. Hydrocarbon-impacted water associated with the West UST was limited to vicinity of the former tank location,while diesel-impacted_ water was documented along the western edge of the property boundary. On 01 December and 05 December 1997 a total of ten soil probe boring (P15 to P25) were established surrounding the East UST area. Locations of the soil probe borings are illustrated on Figure 2. TPH-g, BTE&X were detected in soil samples collected from the probe boring advanced in the area of the East UST area at concentrations as high as 2,100 in and 14 ppm (xylene), respectively. Hydrocarbon-impacted soil associated.with the East UST area appeared to be limited to the former dispenser.area(southern edge of Lindsay Street),and to a depth of sixteen__ to-seventeen feet in depth, in the saturated soil below ground water. TPH-g was detected in six of eleven grab ground water samples collected from the East UST area at concentrations ranging from 53 to 100,000 ppb. BTE&X were detected in eight of eleven samples analyzed at concentrations ranging from 0.55 to 1,700 ppb. The estimated extent of the gasoline- impacted ground water is depicted in Figure 3. In January 1998, four ground water monitoring wells were installed near the West UST area to quantify the hydrocarbon concentration in ground water and determine the direction of ground water flow. Results of the well installation and subsequent sampling delineated the dissolved hydrocarbons and indicated direction of ground water flow generally towards the northeast. Ground water monitoring enabled delineation of the dissolved hydrocarbon plume, with concern for the possible migration of the plume away from the West UST. Locations of the monitoring wells are illustrated on Figure 2. Advanced GeoEnvironmental,Inc.