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• 05 September 2002 GE-NC Project No. 95-0100 Page 3 of 9 ' encountered to depths as great as 35 feet bsg. The analytical results of soil samples from borings B I and B2 are summarized on Table 2. On 22 February 1995,two additional borings, B3 and B4, were drilled north and south of the former fuel dispenser island by GAS. The only hydrocarbons detected in soil samples collected from the borings were Iow concentrations of BTEX in the 35 foot sample from boring B4. These results indicated that hydrocarbon-impacted soil is present only in the immediate area of the former dispenser island. The analytical results from samples collected from borings B3 and B4 indicted that the samples ' contained no significant concentrations of petroleum hydrocarbons. The analytical results of soil samples collected fi-om borings B3 and B4 are summarized on Table 2 (see Appendix A) ' 3.3. CORRECTIVE ACTION PLAN - FEASIBILITY TESTS On 02 October 1995, two soil borings were drilled at the site under the supervision of AGE. Borings VE I and VE2 were advanced to depths of 40 and 35 feet bsg, respectively. Both borings were dual-completed as soil vapor extraction wells with two 2-inch diameter PVC casings. The maximum concentrations of TPH-g and benzene were detected in a soil sample from well VE 1 at 15 feet bsg (VE I-15) at concentrations of 16,000 ppm(parts per million or mg/kg, reported as micrograms per gram) and 4.6 ppm, respectively. Toluene, ethylbenzene and xylenes were detected ' in samples from both VE1 and VE2 at concentrations ranging from 0.0087 ppm (ethylbenzene in sample VE2-20) to 2,000 ppm(xylenes in VEI-15). The analytical results of soil samples collected are summarized on Table 2, ' During installation of the soil vapor extraction wells a soil sample amp e was collected for physicochemical and microbiological analysis. Both the physicochemcial analysis and the microbiological enumeration ' of the sample indicated generally favorable conditions for bioremediation and a high percentage of existing biodegrading microbes. The soil had less than optimal concentration of nitrates,and slightly more potassium. Based upon the analytical results, it appears that a program of biostimulation may ' be successful at the Franklyn Cole site. On 18 October I995, an 8-hour soil vapor extraction(SVE)pilot test was conducted. This pilot test was performed to provide vapor extraction feasibility data for initiation of a full scale remediation ' system. The in-situ SVE test performed at the site yielded acceptable performance results. Vacuum readings at the extraction well(VE-1)ranged between 1.4 and 2.35 inches of water.At VE-2,Iocated 15 feet southeast from VE-1, the initial vacuum was 0.07 inches of water, measured from the lower screen interval. After four hours the influence increased to 0.085_inches__The vacuum measured at _— VE-2 w8 plotted versus distance from the extraction point (VE-1) on a semi-logritbrnic scale. The graph represents the theoretical radius of influence of the extraction well. In soil at the site (sandy- gravel) it appears that.a vacuum of 0.1 would be great enough to volatilize hydrocarbons. A ' theoretical radius of influence of approximately 15 feet could be derived from the graphed data. In a practical application, an-effective radius of influence of approximately 10 feet is more likely to occur. Advanced GeuEnvironmentat,Inc.