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i Ile 03 March 2005 AGE-NC Project No 98-0452 ' Page 5 of 6 No other analytes were detected at or above laboratory reporting limits for the samples submitted Iduring the second,third and fourth quarters of 2004 Analytical results of ground water samples are summarized in Table 2 The laboratory reports(CTEL Project Nos CT214-0406263,CT214-041002 ' and CT214-0412128),quality assurance/quality control(QA/QC)reports and chain of custody forms are included in Appendix D Documents confirming the upload of laboratory electronic deliverable format (EDF) files and depth to water measurements to GeoTracker are included in Appendix E 4.0. SUMMARY AND CONCLUSIONS Based upon data collected from the site, AGE concludes the following I • Average depths to water at the site have remained relatively stable since monitoring began in September 2000 A graph depicting the depths to water for 2003 and 2004 is included in Appendix F • During the second quarter monitoring event, ground water flow was southwest towards a trough in the potentiomctric surface, at a hydraulic gradient of 0 002 ft/ft During the third quarter monitoring event, the ground water flow was westward towards a trough in the potentiometric surface, at hydraulic gradients ranging between 0 0016 ft/ft and 0 0035 ft/ft During the fourth quarter monitoring event, the ground water flow was west-northwest towards a trough in the potentiometric surface, at hydraulic gradients ranging between 0 003 ft/ft and 0 004 ft/ft In general, the dominant ground water flow direction appears to be south-southwest to west-northwest I • TPH-g was reported in monitoring wells MW-4 and MW-5 in the second, third and fourth quarters and in MW-2 in the second and third quarters at concentrations ranging between I 110 µg/1 (MW-2, third quarter) and 1,700 µg/l (MW-4, fourth quarter) • The BTEX constituents ethylbenzene and xylenes were detected all three quarters in MW-4 at concentrations ranging from 2 3 µg/l(xylenes,fourth quarter)to 40 µg/1(xylenes,second ' quarter) • The fuel additive MTBE was detected in monitoring wells MW-2 through MW-5 in all three monitoring events, at concentrations ranging between 5 7 µg/l (MW-3, fourth quarter) and 390 pg/l (MW-2, second quarter) In wells MW-2 and MW-5, the TPH-g concentrations generally match the MTBE concentrations, since the analytical laboratory(CTEL) includes MTBE in the reported TPH-g concentrations,the TPH-g concentrations in wells MW-2 and MW-5 are most likely solely MTBE detections I • The fuel additive TAME was detected in MW-2 at a concentration of 3 4 �ig/1 in the second quarter IAdvanced GeoEnvironmental,Inc I