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' 15 June 2004 • AGE-NC Project No 01-0815 ' Page 6 of 8 ' MTBE was detected in soil samples collected frbm borings MW2 and MW4 at a maximum concentration of 0 31 mg/kg in sample MW2-35 by EPA method 8260 ' No additional analytes were detected at or above laboratory detection limits In the samples analyzed Analytical results of soil samples are summarized on Table 1 The laboratory reports(CTEL Project No CT214-0403161), quality assurance and quality control (QA/QC) report and chain-of-custody forms are included in Appendix F A plane view map showing the extent of adsorbed petroleum hydrocarbon contamination Is shown in Figure 5 Cross sectional views showing the extent of adsorbed petroleum hydrocarbon contamination are depicted in Figures 6 and 7 1 3 3 GROUND WATER GRADIENT AND FLOW DIRECTION At the time of the March 2004 sampling event, depths to ground water ranged from 28 76 (MW-2) feet to 29 50 (MW-1) feet below the tops of the well casings Ground water elevation at the site averaged approximately 18 06 feet below mean sea level (MSL)(Table 3) During this monitoring event,the ground water level in well MW2 was 3 64 feet below the top of the well screen,indicating • that the well is properly screened and representative of shallow ground water conditions Wells MW1, MW3 and MW4 were at least 0 82 to 5 87 feet above the tops of the well screen, indicating the wells are "flooded" and may not give a representative ground water sample Ground water flow was inferred to be flowing towards the southeast with an average hydraulic gradient of 0 003 foot/foot Figure 8 illustrates the contoured ground water elevations as measured ' on 30 March 2004 ' 3 4 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in ground water samples collected from the wells at a maximum concentration of 82,000 micrograms per liter(µg/1)in samples from well MW2 BTEX compounds were detected in ground water samples collected from wells MW1 through MW4 at maximum concentrations of 6,300 gg/l benzene(MW3),4,000 gg/1 toluene (MW2), 1,100 µg11 ethylbenzene(MW2)and 5,200 ' µg/1 total xylenes (MW2), respectively MTBE was detected in ground water samples collected from wells MW1 through MW4 at a maximum concentration of 11,000 gg/1 in sample MW2 1,2-DCA was detected in ground water samples collected from well MW2 at a concentration of 4 6 µg/1 in well MW2 No other analytes were detected at or above laboratory detection limits in the ground water samples . analyzed The analytical results of the ground water samples collected on 30 March 2004 are ' Advanced GeoEnvi ron mental,Inc 1