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' 22 December 2003 . AGE-NC Project No 98-0433 ' Page 3 of 5 ' 3.0. FINDINGS Ground water elevations were determined by subtracting the measured depths-to-water from the ' surveyed casing elevations Ground water flow directions were determined by contouring the water elevations on a scaled site plan (Figure 3) The impact of the unauthorized release on ground water was quantified by laboratory analysis of the samples collected 1 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION ' Depth to ground water in wells ranged from;P 15 to 27 79 feet feet below well casing tops The ground water elevations at the site ranged from 30 MW;S feet ( to 31 11 feet (MW-7) above mean sea ' level (msl) The data indicates an average decrease of the ground water elevation in most wells of 2 4 feet since the previous quarterly monitoring event Depth to ground water and calculated elevation data are presented in Table 1 ' Theound water a to mound under the Lube /Truck Wash and flow away to the southeast �' appears Ba Y and northwest at a gradient of approximately 0 0005 ft/ft and 0 002 f1/ft, respectively At the ' northwest edge of the site, the gradient is determined to be toward the north-northeast with a hydraulic gradient of 0 004 feet/feet (Figure 3) 1 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES ' TPH-g was detected in the ground water samples collected from MW-1, MW-6, MW-8 and MW-9 at concentrations as high as 3,200 micrograms per liter (�ig/l) in MW-6 TPH-d was detected in the ' ground water samples collected from wells MW-1 and MW-6 at concentrations of 26 milligram per liter(mg/1) and 31 mg/l, respectively r ' One or more BTEX compound were detected in samples MW-1 and MW-6 The maximum concentrations included 18 µg/l of benzene, 3 9 pg/1 of toluene, 8 7 µg/1 of ethylbenzene in MW-6 and 49 µg/1 of xylenes in MW-1 ' MTBE was detected by EPA method 8260 in samples MW-1, MW-8 and MW-9 at concentrations of 2,000 µg/1, 220 gg/1 and 1,900 µg/l, respectively TAME was detected in samples MW-1,MW-8 ' and MW-9 at 53 µg/1, 18 pg/l, and 22 µg/l,respectively Target analytes were not detected at or above laboratory reporting limits in the water sample collected from the domestic well (DW-1) on-site ' Analytical results from ground water samples are summarized in Table 1 The laboratory report (CalTech ID CT214-0311064),quality assurance and quality control(QA/QC) and chain-of-custody 1 Advanced GeoEnvironmental,Inc. 1