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1 S <br /> 10 August 2001 <br /> AGE-NC Project No 97-0301 <br /> ' Page 3 of 5 <br /> 3 1 RELATIVE GROUND WATER ELEVATION AND GRADIENT <br /> ' The depths to ground water in wells MW-1 through MW-7 were measured between 28 97 and 29 68 <br /> feet below the tops of well casings, ground water elevations were calculated to be between 16 66 feet <br /> ' and 16 89 feet below mean sea level Ground water elevation at the site decreased an average 2 20 <br /> feet between the March 2001 and the June 2001 ground water monitoring events The ground water <br /> elevation data for MW-1 through MW-7 during the June 2001 ground water monitoring event is <br /> ' depicted in Figure 3 Groundwater flow direction for the area bound by wells MW-1,MW-3,MW-4 <br /> and MW-6 was inferred southeast at a gradient of 0 002 ft/ft or less, or approximately 11 feet per <br /> mile(Figure 3), ground water flow direction for the area bound by wells MW-1, MW-2 and MW-6 <br /> ' was inferred northeast at a gradient of 0 001 or less, or approximately 5 feet per mile, ground water <br /> flow direction in the area of well MW-7 was inferred to be toward the northwest at an undetermined <br /> gradient <br /> ' Ground water flow direction in the area bound b al - - <br /> y Tank-Line e w ells MW-2, MW 3 and MW 4 <br /> ' was inferred to be towards the southeast at a gradient of 0 004 ft/ft or less, or approximately 21 feet <br /> per mile (Figure 3), ground water flow direction in the area of Cal-Tank Line well MW-1 was <br /> inferred to be toward the northeast at an undetermined gradient <br /> 3 2 LABORATORY RESULTS OF MONITORING WELL GROUND WATER SAMPLES <br /> ' A total of seven ground water samples were submitted to a DHS-certificd laboratory in June 2001 <br /> TPH-g was detected in water samples collected from wells MW-1, MW-5 and MW-7 at <br /> concentrations of 29,000 micrograms per liter(µg11), 68µg/1 and 55,000µg11,respectively, however <br /> 1 the laboratory reported the samples from MW-1,MW-5 and MW-7 as having significant unmodified <br /> or weakly modified gasoline TPH-d was detected in the water samples collected from MW-1,MW-4 <br /> ' and MW-7 at concentrations 3,600µg/1, 89,ug/1 and 3,800µg/l,respectively,however the laboratory <br /> reported the samples from MW-1 and MW-7 as having significant gasoline range compounds, and <br /> the sample from MW-4 as having significant diesel range compounds TPH-k was detected in the <br /> ' water samples collected from MW-1, MW-4 and MW-7 at concentrations of 3,200µg/l, 110µg/1 <br /> and 3,300µg11, respectively <br /> ' BTEX compounds were detected in water samples collected from wells MW-1, MW-4, MW-5 and <br /> MW-7 at concentrations ranging as high as 8,200µg/I (MW-7, benzene) <br /> ' MTBE was detected in a water sample collected from MW-1 utilizing EPA Method 8260 Modified <br /> at a concentration of 13 µg/l, 1,2-DCA was detected in samples collected from MW-1 and MW-7 <br /> ' at 320µg/1 and 830µg/l, respectively, EDB was detected in the water sample collected from MW-1 <br /> at a concentration of 12µg/1 No other fuel oxygenated or lead-scavenger compounds were detected <br /> during the June 2001 laboratory analysis Analytical results of the ground water samples are <br /> Advanced GeoEnvironmental,Inc <br />