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i 23 April 2001 AGE-NC Project No 97-0301 Page 3 of 5 3.0. FINDINGS ' Ground water elevation, flow direction and gradient were determined from field data collected on 30 March 2001, the contaminant Impact to ground water was assessed from the ground water ' laboratory data ' 3 1 RELATIVE GROUND WATER ELEVATION AND GRADIENT The depths to ground water in wells MW-1 through MW-7 were measured between 26 80 and 27 46 ' feet below the tops of well casings,ground water elevations were calculated to be between 14 44 feet and 14 73 feet below mean sea level Ground water elevation at the site increased an average 2 10 feet between the December 2000 and the March 2001 ground water monitoring events, increasing 1 ground water elevation has been observed at the site at least since the September 2000 ground water monitoring event The ground water elevation data for MW-1 through MW-7 during the March 2001 ground water monitoring event is depicted in Figure 3 Ground water flow direction for the area ' bound by wells MW-1 through MW-6 was inferred east-southeast at a gradient of 0 003 ft/ft, or approximately 16 feet per mile(Figure 3),ground water flow direction in the area of well MW-7 was inferred to be toward the north at an undetermined gradient 3 2 LABORATORY RESULTS OF MONITORING WELL GROUND WATER SAMPLES A total of seven ground water samples were submitted to a DHS-certified laboratory in March 2001 TPH-g was detected in water samples collected from wells MW-1 and MW-7 at concentrations of 21,000 and 61,000 micrograms per liter (µg11), respectively, however the laboratory reported the samples from MW-1 and MW-7 as having significant unmodified or weakly modified gasoline ' TPH-d was detected in the water samples collected from MW-1,MW-2,MW-4,MW-5, and MW-7 at concentrations as high as 5,500µg11(MW-7), however the laboratory reported the samples from MW-1 and MW-7 as having significant gasoline range compounds, the samples from MW;2 and MW-4 as having no recognizable diesel pattern and the samples from MW-4 and MW-5 as having significant oil range compounds TPH-mo was detected in the water samples collected from MW-4, and MW-5 at concentrations of 270 and 710 ug/l, respectively ' BTEX compounds were detected in water samples collected from wells MW-1 MW-4 and MW-7 p p , at concentrations ranging as high as 11,000µg/l (MW-7, benzene) ' - 1 and 890 1 1,2-DCA was detected in samples collected from MW-1 and MW 7 at 80 µgl , respectively, EDB was detected in the water sample collected from MW-I at a concentration of 7 µg/1 Fuel oxygenated compounds were not detected during the March 2001 laboratory analysis Analytical results of the ground water samples are summarized in Tables 2 and 3 The laboratory 1 Advanced CcoEnvironmentai,Inc I 1 I