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1 23 December 2003 AGE-NC Project No 98-0497 ' Page 3 of 4 ' 3 2 ANALYTICAL RESULTS FROM GROUND WATER SAMPLES The analytical results from the 22 September 2003 ground water sampling event are as follows • TPH-g was detected in well MW-1 at a concentration of 310 micrograms per liter(µg/l) The laboratory report noted that strongly-aged gasoline or diesel compounds were significant and ' there was a lighter than water immiscible sheen showing product present, • TPH-d was detected in MW-1 and MW-3 at concentrations of 9,700 µg/1 and 56 µg/l, respectively The laboratory report indicated significant amounts of unmodified or weakly modified diesel in the sample taken from well MWA along with a lighter than water immiscible sheen The sample taken from MW-3 had significant diesel range compounds ' with no recognizable pattern, • BTEX compounds were not detected in the five ground water samples analyzed, we • Fuel additives were not detected in the five ground water samples analyzed 5a� -2 0 ' Z' Laboratory results of water samples analyzed for petroleum hydrocarbons are summarized in ' • Table 2 Copies of the laboratory reports for the quarterly monitoring event(MAI Lab IDs 0309438- 001 through 0309438-005), QA/QC reports and chain-of-custody form are in Appendix B 4.0. SUMMARY AND CONCLUSIONS ' The findings of the 22 September 2003 ground water monitoring event include the following • Measured ground water elevation was approximately 41 83 feet below MSL,and was within ' the screened interval of each monitoring well Ground water flow direction near the former UST location was to the east-northeast with an average gradient of 0 007 ft/ft Historically, flow direction at the site has been toward the east or has had no observable gradient • Contamination by TPH-g and TPH-d was encountered in the ground water sample collected and analyzed from MW-1 The detected concentrations ofTPH-d in samples collected from ' MW-I have fluctuated significantly during the past seven monitoring events Prior to June 2002, the TPH-d concentrations in well MW-I had exhibited an overall declining trend ' _ _ • TPH-d was detected in MW-3 for the first time since monitoring was initiated, at 56 µg/1 TPH-g and TPH-d were not detected irI-MW-2, MW-4 and MW-5 AmTbf 0'1 nIs"fk t-t • TPH-g, BTEX compounds and fuel additives were not detected in ground water samples ' analyzed from wells MW-2 through MW-5 • Advanced CeoFnvironmental,Inc 1