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l -ilr 19 January 2004 + AGE-NC Project No 96-0235 , " Page 6of8 , • BTEX compounds were detected in water samples collected from MW-10 and EW-1 The , Imaximum BTEX concentrations were detected in the sample from EW-1 The BTEX I concentrations in sample EW-1 were above the DHS Maximum Contaminant Level(MCL) 1 ` in drinking water , I • MTBE was detected by EPA Method 8260B in the shallow-screened wells MW-10, MW-12A,MW-13A,MW-14A and EW-1 and in the deep-screened wells MW-9,MW-11B, ' MW-12B,MW-13B and MW-14B at concentrations as high as 370 µg/1(EW-1) With the exception of MW-14A,the MTBE concentrations were above the DHS'PnmaryMCL,of 13 t µg/l in drinking water,the MTBE concentration in MW-14A exceeded the DHS' Secondary ' MCL of 5 µg/1 in drinking water • The concentration of 1,2-DCA detected in ground water sample MW-14B exceeded the , ' DHS' MCL ` ` In the former UST cluster area, the most impacted`ground water appears to be centered ' around EW-1 and MW-10 The vertical extent of the contamination plume, as well as the lateral extent east and south of the former UST cluster, are not well defined f ' Based on the data collected in September from the former UST No 3 area, AGE finds ' The ground water flow direction at the shallow-screened level was inferred to be towards the ' east-northeast at a gradient of 0 005 ft/ft, ground water flow direction at the deep-screened level was inferred to be toward the south-southwest at a gradient of 0 015 ft/ft • TPH-g was detected in the samples collected from MW-1, MW-2 and EW-2 at !; concentrations as high as 29;000 µg/l(MW-2), TPH-d was detected in the sample collected from MW-2 at a concentration of 30[g/1 Various BTEX compounds were detected in water samples MW'-I, MW-2 and EW-2 TheBTEX concentrations in the samples from wells ' MW-I and MW-2 were exceeded the respective MCLS for drinking water • MTBE was not detected in any of the ground water samples collected from the former UST ' No 3 excavation area However, 1,2-DCA was detected in water samples MW-2 and EW-2 j at concentrations exceeding the MCL for drinking water ` , I II Based on the data collected in November from the former UST cluster area, AGE finds , p r • The shallow-screened data delineate a radial ground water flow pattern, with' a net flow towards the east at a gradient of 0 008 ft/ft,the deep-screened data delineated a ground water flow direction toward the east-northeast at a gradient'of 0 001 ft/ft Ground water gradient ' and flow direction observed during the fourth quarter 2003 were similar to, the previous quarter , II { ' N , Advanced Gen Environmental,Inc a I I 1 I YI I I r ' E I