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i 30 August 2005 . AGE-NC-95-0185 Page 3,of 4 ' 3.1.. GROUNDWATER GRADIENT AND FLOW DIRECTION During the May 2005 sampling event,the groundwater elevation at the site-ranged from 34.10 feet (MW-2) to 35.03 feet (MW-4) above mean sea level (MSL'); the average ground water elevation ' during the May 2005 sampling event was 34.75 feet above MSL;the average ground water elevation at the site increased approximately 0.1feet since the previous monitoring event in February 2005. ' The ground water elevation determined.from the monitoring well MVV-2 casing-,was likely incorrect due to casing modifications(damage and repairs)conducted prior to the ground water level gauging ' event and was therefore discounted.from the ground water elevation modeling. The ground water flow direction was inferred to be toward the northwest at a gradient of approximately;0.002 foot/foot (ft/ft)near the former UST locations (Figure 3). 3.2. LABORATORY RESULTS OF GROUND WATER SAMPLES TPH-d, TPH-g, BTEX compounds and-fuel additives were not detected in the sample from wells MW-2 and MW-3.TPH-g and TPH-d were detected in the samples collected from wells MW-1 and �. MW-4 during the May 2005 sampling at concentrations as high as 220,000 micrograms per liter (pg/1) and 1,500,000 µg/1', respectively. BTEX compounds were detected in the sample collected from well MW-4 at concentrations of 2.9 µg/1, 274 µg/1, 13 pg/l,and 5.9 µg11,respectively. Current and previous analytical results are summarized in Tables 2 and 3. The laboratory reports (CTEL Project No:CT214-0505138),quality control/quality assurance(QA/QC)reports and chain of custody forms are included in Appendix C. GeoTracker confirmation pages of the submitted- laboratory ubmittedlaboratory electronic deliverable format(EDF)files and depth to water measurements are provided in Appendix D. ' 4.0. CONCLUSIONS Based7 on the data collected during the May 2005 monitoring period, AGE concludes: • Visual free product has been resent intermittently in wells MW-1 and MW-4 since the:June p p 2002 groundwater monitoring event.Well MW-5 was inaccessible this quarter,so it was not ' monitored. • Ground water ranged between 34.10 feet and 35.03 feet above MSL and was inferred to flow ' toward the northwest at a gradient of approximately 0.002 ft/ft, which• appears to be particularly, steep when compared to historical flow gradients recorded at the site. Advanced GeoEnvironmental,Inc.