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_ 06 December 1995 AGE-NC Project No. 95-0100 Page 3 of 13 3.2. LOGGING Soil was extruded from the second brass tube and screened for the presence of organic vapors using a PID, The readings were recorded on the boring logs. The soil was then described in accordance with the United Soil Classification System. Boring logs are included in Appendix A. 3.3. VAPOR EXTRACTION WELL COMPLETION Both borings were dual-completed as 2-inch diameter soil vapor extraction wells (VEI and VE2). Well VEI was backfilled from depths of 35 to 40 feet bsg with bentonite. VEI was then completed using 0.020 slotted PVC screen from a depth of 20 to 35 feet bsg; blank PVC screen was used from surface grade to 20 feet bsg. The filter pack (#2 sand) was installed from a d{-,pth of 20 to 35 feet bsg. A two-foot bentonite plug was then placed from 18 to 20 feet bsg. A second slotted PVC casing was installed from depths of 5 to 18 feet bsg; blank PVC screen was used from surface grade to 5 feet bsg. A second filter pack was installed from 3 to 18 feet bsg, and a bentonite plug was placed from — 1.5 to 3 feet bsg. Portland cement was used to backfill the annular space from surface grade to a depth of 1.5 feet bsg. Well VE2 was dual completed using slotted PVC screen from 2,5 to 15.5 feet bsg and blank casing from surface grade to 2.5 feet bsg for one completion, and slotted PVC screen from 20 to 35 feet bsg with blank casing from surface to 20 feet bsg for the second completion. A filter pack (92 sand) was installed from 2 to 35 feet bsg. Bentonite pellets were used to make a I--foot plug and the annular space was then grouted to surface grade with Portland cement. 3.4. ANALYTICAL RESULTS OF SOIL SAMPLES Four soil samples from well VEI and two from well VE2 were analyzed by AAL. TPH-g was detected in samples from well VEI at concentrations up to 16,000 µgig (parts per million: ppm); TPH-g was not detected in the samples from VE2. Benzene was detected in sample VEI-Z5'at 4.6 ppm; toluene, ethyl benzene and xylene were detected _ in samples from both VEI and VE2 at concentrations ranging from 0.0087 ppm (ethyl benzene, sample VE2-20) to 2,000 ppm (VE1 N?. }.`Analytical results of the soil samples are summarized in Table 1. The laboratory report and chain-of-custody forms are included in Appendix B, T Sample VEI-10 was submitted for microbiological analysis. Analysis of the sample indicated that most physiochemical parameters of -..kern are within an acceptable range for supporting bioremediation, although nitrate concent r al ions were a little low, and potassium concentrations were a little high. Furthermore, specific hydrocarbon degraders represent more than 21% of the overall