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i i11 August 2004 AGE-NC Project No 95-0141 iPage 3 of 5 i3 1 GROUND WATER ELEVATION AND GRADIENT At the time of the June 2004 monitoring event, depths to ground water ranged from 20 47 feet to 21 65 feet below the tops of the well casings(btoc) Ground water elevations at the site ranged from 13 18 feet below mean sea level(MSL)in well MW-12A to 14 04 feet below MSL in well MW-8B (Table 1) The tops of the well screens in MW-3 and MW-5 were drowned by approximately 8 6 to ' 7 5 feet, respectively Wells MW-5, MW-7, MW-8A through MW-12A and EX-1 were used to determine ground water flow direction and gradient for shallow ground water The shallow ground water was Inferred to flow I generally toward the east-southeast,at a gradient of 0 002 foot/foot Figure 3 Illustrates the contoured shallow ground water elevations as measured on 17 June 2004 Ground water elevation data from well MW-3 was not used to determine ground water gradient and flow direction, the data appears to be anomalous Wells MW-6 and MW-8B through MW-12B were used to determine ground water flow direction and gradient for the deep ground water zone The deep ground water was Inferred to flow generally toward the east-southeast, at a gradient of 0 002 foot/foot Figure 4 illustrates the contoured deep ground water elevations as measured on 17 June 2004 3 2 ANALYTICAL RESULTS FROM GROUND WATER SAMPLES The analytical results of the ground water samples were as follows • TPH-g was detected in ground water samples collected from wells MW-3, MW-5, MW-6, MW-8B,MW-11B and EX-1 at concentrations ranging from 100 micrograms per liter(µg/1) in MW-5 to 120,000 µg/1 in EX-1 ' 0 Various BTEX compounds were detected in samples MW-3, MW-8B,MW-11B and EX-1 at concentrations as high as 8,700 µg/l of benzene, 35,000 µg/1 of toluene, 4,900 µg/1 of ' ethylbenzene and 26,900µg/1 of xylenes These high concentrations were all from well EX-1 • 1,2-DCA was detected in ground water samples collected from all wells except MW-6, MW-9A, MW-10A,MW10-B,MW-11A, MW-12A and MW-12B 1,2-DCA was detected ' at concentrations ranging from 4 3 µg/l (MW-8B) to 210 µg/1 (EX-1) • EDB was detected in ground water sample EX-1 at a concentration of 300 µg/1 ' The areal extent of TPH-g- and 1,2-DCA-impacted shallow and deep ground water is illustrated on Figures 5 and 6,respectively Laboratory results ofwater samples analyzed are summarized in Tables ' 2 through 5 The laboratory reports for the quarterly monitoring event(CTEL Project No CT214- • 0406168), quality assurance and quality control (QA/QC) reports and chain of custody form are ' Advanced Geo Environmental,Inc I