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i 14 December 2000 AGE-NC Project No 99-0559 Page 9 of I l 4 4 GROUND WATER ELEVATION AND GRADIENT The ground water elevation on 02 February 2000 ranged from 22 60 to 22 95 feet below mean sea Ilevel (MSL) The depth to water was 47 26 to 48 56 feet below the well heads The top of the ground wafter table occurred within the screened intervals of the wells The ground water elevation from monitoring well MW-2 was not included in the calculation of the first ground water flow direction Ground water was inferred to be flowing to the south (Figure 7) with a hydraulic gradient of 0 005 feet/feet The ground water elevation on 01 September 2000 ranged from 24 84' to -24 34 feet below MSL The depth to water was 49 44 to 50 33 feet below well heads The top of the ground water table occurred within the screened intervals of the wells The water elevation was corrected 0 25 inches for the presence of product over the water table Ground water was inferred to be flowing to the northwesterly (Figure 8) with a hydraulic gradient of 0 008 feet/feet lie 45 RESULTS OF GROUND WATER SAMPLE ANALYSIS Two grab ground water samples were collected from soil bonngs established on the site TPH-g was detected in ground water samples collected from B3 and 134, at concentrations as high as 110,000 micrograms per liter (4g11) Benzene was detected at concentrations as high as 19,000 µg11 (134) MTBE was detected at a concentration as high as 42,000µg/I in sample B4-W Ground water samples were collected during quarterly monitoring on 02 February 2000, samples were not collected from MW-2 due to free product observed during purge process TPH-g was detected in the first ground water samples collected from MW-1, MW-3, and MW-4 at concentrations as high as 84,000 µg11 (MW-1) Benzene was detected at concentration as high as 13,000 µg/l (MW-1) Other BTEX compounds were detected at concentrations as high as 42,000 I (xylene MW-4) During the 25 February 2000 well sampling, TPH-g was detected in the ground water sample from well MW-2 at a concentration 110,000 4g11,benzene was detected at 11,000 4g/1 in the same sample MTBE was detected at 44,000 µg11 in well MW-2 during the 25 February 2000 sampling During the 05 September sampling event, TPH-g was detected in well samples MW-1 and MW-4 at concentrations as high as 59,000 ,ug/1 in well MW-4 BTEX compounds, were detected in same samples at concentrations as high as 9 700,ug/1 (toluene) sMTBE was detected in the September samples MW-1 and MW-4 at concentrations of 4,700µg/1 and 14,000 µg11, respectively by EPA Method 8260 No other fuel oxygenates were detected in any of the samples