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25 August 1999 AGE-NC Project No 98-0448 Page 8 of 10 I First encountered ground water is approximately 17 feet bsg, first observed saturated soil was between 20 feet bsg and 25 feet bsg • General lithology beneath the site was noted on boring logs (Appendix A) and consisted of , a brown, moist, very stiff clay with some silt and fine sand between 10 feet bsg and 15 feet bsg Generally,a brown to pale green/gray, moist to saturated, medium dense to dense, sand ' with some silt was between 15 feet bsg and 25 feet bsg A pale green/gray, saturated, medium dense to dense, poorly graded, sand with some silt was generally encountered at depths between 25 and 30 feet bsg A brown to pale green/gray, moist to saturated, medium I dense to dense, sand with some silt was generally encountered between 30 feet bsg and 35 feet bsg A pale green/blue/gray, moist, hard silt with some fine sand and clay was encountered at 45 feet bsg ' Laboratory analysis of six soil samples detected TPH-g, BTEX and MTBE in one sample, no other petroleum hydrocarbon compounds were detected in any of the analyzed soil Isamples • The results of the microbial enumeration and physicochemical analysis indicated that selected microbial enumeration (hydrocarbon-degrading microorganisms) were detected at 1 CFU (colony forming units)per gram The laboratory indicated that these physicochemical conditions at the site were well within the range necessary to support microbial growth and I bioremedial activity However, the laboratory reported that the percentage of microbial biodegraders were significantly lower in the EW1-25 soil sample, possibly due to the presence of alternative carbon sources (abundance of organic debris) • Ground water flow direction for the area bound by wells MW-2. MW-3 and MW-5 through MW-8 was generally toward the southwest at a calculated gradient of 0 007 ft/ft, or approximately 37 feet per mile (Figure 3), ground water flow direction for the area bound by wells MW-1 and MW-4 was generally toward the south-southwest • Ground water was approximately 26 feet above the screened interval in monitoring well MW-413, therefore this well is "drowned", and will not yield a sample representative of shallow ground water - - - I • Ground water elevation at the site decreased an average 0 53 feet between the March and June 1999 ground water monitoring events , • TPH-g was detected in ground water samples collected from wells MW-1, MW-2, MW-4A, MW-413, MW-6 and MW-8 at concentrations between 86 micrograms per liter (,ug/l) and 65,000µg/1, the Iaboratory reported unmodified or weakly,modified gasoline was significant Ior heavier gasoline range compounds were significant • IAdvanced GeoEn%ironmeniai,Inc