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31 August 2005 i' AGE-NC Protect No 96-0232 Page 14 of 30 beneath the site is depicted in cross-sectional views AA ', B-B', C-C', D-D' and E-E' (Figures 5 through 9) Saturated soil was generally encountered at depths between approximately 10 feet and 20 feet bsg in all bonngs, initial ground water levels were generally measured at depths between 5 feet and 15 feet bsg utilizing a Solinst water level meter Based on the subsurface soil distribution, AGE developed a preliminary subsurface model of the stratigraphy/hydrostratigraphy consisting of a vadose zone and five informal hydrogeologic zones (First Zone,Second Zone,Rocky's Upper Zone,Secondary Zone and Primary Zone) Hydrogeologic zones may be defined as significant vertical intervals of soil having significant lateral extent and having similar hydrogeologic characteristics (i a hydraulic conductivity, transmxssivity, etc ) over its vertical and horizontal extent AGE has informally identified the five informal hydrogeologic zones in geologic cross sections C-C; D-D' and E-E' (Figures 7, S and 9, respectively) as having significant intervals of apparently porous to semi-porous grained soil separated by significant intervals of finer-grained, less permeable soil, the vadose zone and the five hydrogeologic zones identified are as follows (depths are approximate and can vary by several feet across the site) • Vadose Zone - Extending from surface grade to 10 feet bsg (approximate ground water level) The vadose zone is predominantly charactenzed by combinations of fine grained material (silts, sandy clays, sandy silts and silty sands) from surface grade to 10 feet bsg • First Zone - Located between 10 feet (approximate ground water level) and 35 feet bsg, consists primarily of combinations of fine grained material(silts,sandy clays,sandy silts and silty sands) • Second Zone - Located between 40 and 60 feet bsg, consists primarily of combinations of semi permeable silty sands and permeable fine-medium sands with limited minor fine grained material • Rocky's Upper Zone) - Located between 70 feet and 75 feet bsg, consists primarily of permeable to semi-permeable, silty fine sand and fine to medium sand • Secondary Zane - Located between 90 feet and 110 feet bsg, consists primarily of permeable, fine-coarse grained sand • Primary Zone - Located at depths greater than 120+ feet bsg, permeable, fine to medium sand On 15 May 2000, three soil samples (P21-20, P25-15 and P27-20) were submitted for laboratory ' analysis of porosity, moisture and density Porosity of P21-20 was measured at 37 8 percent, • moisture at 21 2 percent and the soil was characterized as a sandy clay Sample P25-15 had 37 S Advanced GcoEnvironmental,Inc