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12 February 2002 <br /> AGE-NC Project No. 98-0450 <br /> ' Page 3 of 6 <br /> ' sample ports. These samples were labeled, placed in a pre-chilled cooler and transported under <br /> chain-of-custody to MAI. The samples were analyzed for: <br /> ' • TPH-g in accordance with EPA Method 8015 Modified and <br /> • BTEX and MTBE in accordance with EPA Method 8020. <br /> ' The results of the laboratory analysis are summarized in Table 4. <br /> ' 3.0. FINDINGS <br /> rGround water elevation, flow direction and gradient were determined from field data collected on <br /> 24 September 2001.Ground water flow direction was determined by contouring the water elevations <br /> ' on a scaled site plan (Figure 3). The contaminant impact to ground water was assessed from the <br /> ground water laboratory data. <br /> ' From field data collected at the S VE remediation system between early August and early December <br /> 2001, AGE determined the average TPH-g concentration, the average flow rate and calculated the <br /> approximate mass and volume of gasoline removed. <br /> 3.1. RELATIVE GROUND WATER ELEVATION AND GRADIENT <br /> The depths to ground water from the tops of the monitoring well casings were measured at 48.37 to <br /> 49.53 feet. The corresponding ground water elevations ranged from 3.29 to 4.01 feet below mean <br /> sea level. <br /> Since the previous quarterly monitoring event, ground water elevation had decreased an average 2.2 <br />' feet at the site. The ground water elevation data for the well network during the latest ground water <br /> monitoring event is depicted in Figure 3. The ground water flow direction determined during this <br /> monitoring event was toward the south, with a hydraulic gradient of approximately 0.007 (Figure <br /> t 3). <br /> Based on a southerly flow direction within the area contained by the six monitoring wells, wells <br /> MW-5 and BMW 2 are down-gradient from the former dispenser system and the formerUST-area. -. -- -- <br /> Table 1 shows the screen intervals for monitoring wells BMW-3, BMW-4 and BMW-5 and the <br />' assumed screen intervals for monitoring wells BMW-1 and BMW-2.The analytical results obtained <br /> are believed to be representative of the dissolved hydrocarbon concentrations in the shallow ground <br /> water at the site as the wells are screened across the ground water table. <br />' Advanced GeoEnvironmental,Inc. <br /> 1 <br />