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06 October 2005 . AGE-NC Project No 01-0827 Page 5 of 7 the laboratory analysis of the ground water samples 3 1 STRATIGRAPHY AND DEPTH TO GROUND WATER Clay and silt with a brown color was encountered from a depth of approximately 15 feet to 25 feet bsg Brown silty sand was observed at 24 feet bsg with a lower silt contact also observed below 25 feet bsg A layer of sand was present between 28 feet and 30 feet bsg Silty sand was encountered again from at 35 feet bsg Ground water was encountered at a depth of 35 feet bsg during drilling The soil boring log is provided in Appendix B 3 2 GROUND WATER GRADIENT AND FLOW DIRECTION On 12 September 2005,depths to ground water in monitoring wells MW-1 through MW-6 and vapor wells VW-2d and VW-5d ranged from 2181 feet to 23 60 feet below the tops of the well casings (btoc, Table 1) The ground water elevations and gradient were calculated and determined from depth to ground water data from monitoring wells MW-1, MW-3 MW-4 and MW-5 The third Iquarter 2005 ground water elevations at the site ranged from 11 91 feet (MW-5) to 13 00 feet (MW-1) below mean sea level (MSL) The ground water flow direction at the UST release was inferred to be toward the east, at a gradient of approximately 0 01 foot per foot (ft/ft) on-site ' (Figure 3) ' 3 3 ANALYTICAL RESULTS OF SOIL AND GROUND WATER SAMPLES ' No analytes were detected at or above laboratory reporting limits in the soil or grab ground water samples collected and analyzed from boring B18 Based on analysis of the 12 September 2005 ground water samples, TPI -g was only detected in the ground water sample collected from well ' VW-2d at a concentration of 500 micrograms per liter (µg/l) BTEX compounds were detected at concentrations of 54 µg/1 benzene, 3 6 µg/1 ethylbenzene, 2 9 pg/l toluene and 2 6 pg/l xylenes in the ground water sample collected from well VW-2d No additional analytes were detected at or ' above laboratory reporting limits in the samples analyzed The analytical results of water samples are summarized in Tables 2 and 3 A copy of the laboratory ' reports (CTEL Project No CT214-0509096 and 0507084), quality assurance/quality control (QA/QC)reports,and chain of custody forms are included in Appendix D GeoTracker confirmation pages of the submitted laboratory electronic deliverable format (EDF) files are included in ' Appendix E • ' Advanced GeoEnvironmental,Inc I