Laserfiche WebLink
1' <br /> 09 May 2003 <br /> AGE-NC Project No 96-0232 <br />' Page 10 of 16 <br /> 3 4 12 .Second Zone Aquifer <br />' <br /> Ground water elevation data collected in the Second Zone Aquifer (40 to 60 feet bsg) inferred a <br />' radially-inward ground water flow, towards the south in the area of Flag City Chevron wells <br /> MW-6B, MW-8A, MW-9A and MW-10B (Figure 5) West of the Flag City Chevron site ground <br /> water was inferred to flow towards the east Ground water gradients were approximately 0 001 ft/ft <br />' or less near the Flag City Chevron, the Rocky's Restaurant and the Three B's Truck Plaza sites <br />' 3 4 1 3 Secondary Aquifer Zone <br /> Ground water elevation data collected in the Secondary Aquifer Zone(85 to 105 feet bsg) inferred <br />' a east-southeast ground water flow direction(Figure 6) Ground water gradients were approximately <br /> 0 001 ft/ft or less near the Flag City Chevron,the Rocky's Restaurant and the Three B's Truck Plaza <br /> sites <br /> 1 <br /> 3 4 14 Primary Aquifer Zone <br /> Ground water elevation data collected in the PnmaryAquifer Zone(130 to 150 feet bsg)inferred a <br /> southeast ground water flow direction (Figure 7) Ground water gradients were approximately <br /> 0 001 ft/ft or less near the Flag City Chevron, the Rocky's Restaurant and the Three B's Truck Plaza <br /> sites <br /> 3 4 2 Laboratory Results of Ground Water Samples <br />' During the March 2003 sampling event, TPH-g and TPH-d were only detected in the sample <br /> collected from MW-12A at concentrations of 55 µg/1 and 250 µg/l, respectively The laboratory <br />' reports noted that the TPH-d sample chromatogram.had no recognizable patterns Based on further <br /> laboratory review of the TPH-d sample chromatograms,the laboratory has indicated to AGE that the <br /> TPH-d detections from MW-12 did not have typical diesel characteristics, and that the detected <br />' chromatogram peaks were possibly the result of biological interference <br /> MTBE (utilizing EPA Method 8260M) was detected in water samples collected from monitoring <br />' wells MW-6B,MW-8A,MW-9A,MW-9C,MW-11A,MW-1 IB,MW-11D,MW-12B and MW-14 <br /> through MW-18 at concentrations as high as 900 µg/1 (MW-8A), isoconcentration maps displaying <br /> the estimated extent of dissolved MTBE in First Zone and Second Zone aquifer are depicted in <br />' Figures 8 and 9 In addition,MTBE was detected in water samples collected from extraction wells <br /> EW-1, EW-4 and EW-7 through EW-10 at concentrations as high as 96 µg/1 (EW-8), an <br /> Advaneed GeoEnwronmental,Inc <br />