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Ile25 August 2004 <br /> AGE-NC Project No 95-0167 <br />' Page 3 of 4 <br /> BTEX compounds were detected in the water samples collected from monitoring well MW-1 at <br /> concentrations of 5,800 µg/1 of benzene, 6,100 gg/1 of toluene, 1,000 µg11 of ethylbenzene and <br /> 6,000 µg/1 of xylenes <br /> tMTBE was detected in sample MW-1 at a concentration of 36 µg/1 No other fuel additives were <br /> detected at or above laboratory reporting levels in the ground water samples <br /> Analytical results of ground water samples collected during the June 2004 monitoring event are <br /> summarized on Table 2 The laboratory report (CTEL Project No CT214-0407004), quality <br />' assurance/quality control (QA/QC) report and chain-of-custody form are Included in Appendix C <br /> Documents confirming the upload of laboratory electronic deliverable format(EDF)files and depth <br /> to water measurements to GeoTracker are Included in Appendix D <br /> 4.0. SUMMARY AND CONCLUSIONS <br />' Data collected at the site indicates that <br />' • • The ground water flow direction during this monitoring event was toward the northwest at <br /> an average gradient of 0 01 feet/feet Ground water flow at the site has historically been <br /> t towards the northwest <br /> • Moderate to high concentrations of TPH-g and BTEX occur In ground water in the area of <br /> monitoring well MW-1 TPH-g and BTEX concentrations were not detected this quarter in <br />' the samples collected from well MW-2 This is the third consecutive quarter that petroleum <br /> hydrocarbon concentrations were not detected in well MW-2 <br /> • MTBE was detected again this quarter in the sample collected from MW-1 at a concentration <br /> of 36 pg/l, which is above the DHS' Maximum Containment Level (MCL) for drinking <br /> water 1,2-DCA was not detected this quarter in well MW-1 <br />' • The contaminant plume appeared to be confined to the general area of the former UST and <br /> dispenser location at MW-1 TPH-g, BTEX and MTBE all Increased since last quarter,but <br />' the data reflects a trend observed in previous data showing a spike in detected analyte <br /> concentrations between first and second quarter monitoring events Petroleum hydrocarbons <br /> were not detected in perimeter wells MW-2, MW-3, MW-4, MW-5 and MW-6 <br /> In addition, petroleum hydrocarbons were not detected In a grab ground water sample z <br /> collected and analyzed in April 1997 from soil boring P4, south of the former UST location <br /> 1 Advanced GeoEnriron mental,Inc <br />