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1 ' 21 December 2005 . AGE-NC Project No 99-0624 ' Page 3 of 4 ' 32 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in ground water samples collected from wells MW-1, MW-2 and MW-3 at ' concentrations of 1,000 µg/l, 110,000 µg/l and 2,600 µg/1, respectively Total xylenes were only detected in the sample collected from well MW-2 at a concentration of 3 8 µg/l The fuel additive MTBE was detected in samples from wells MWA through MW-3 and MW-5 at concentrations ' between 42 µg/1 (MW-5) and 110,000 µg/1 (MW-2) TAME was detected in samples from wells MW-2 and MW-3 at concentrations of 310 µg/l and 22 µg/l, respectively ' No other constituents of concern were detected at or above laboratory reporting limits in the analyzed samples Previous and current analytical results of ground water monitoring well samples are summarized in Table 2 The laboratory report(CTEL Lab I D No 0507-159) and chain of custody ' forms are presented in Appendix B Confirmation pages of the laboratory electronic digital format (EDF) files and depth to water measurements submitted to the State of California's GeoTracker website are included in Appendix C 4.0. SUMMARY AND CONCLUSIONS ' The following conclusions were drawn from the results of this Investigation ' 0 The depth to ground water at the site was between 54 38 feet and 55 53 feet TOC, the calculated ground water elevations was ranged between 16 10 feet and 16 42 feet below ' MSL • Ground water flow direction in the area of wells MW-1 through MW-6 was Inferred to be flowing towards the south-southeast at a gradient of approximately 0 002 ft/ft Due to the low ' hydraulic gradient at the site, slight variations in ground water measurements or changes of recharge/discharge of the local ground water could greatly modify the inferred ground water flow direction r0 TPH-g was detected in ground water samples collected from wells MW-1 through MW-3 at a maximum concentration of I 10,000 µg11 (MW-2) The appearance of TPH-g at the same ' or similar concentrations of MTBE indicates that the reported concentration of TPH-g is actually an isolated MTBE peak, which falls within the same carbon range ' 0 The fuel additive MTBE was detected in samples from wells MW-1 through MW-3 at a maximum concentration of 110,000 µg/1 (MW-2) Between May and July 2005, significant MTBE increases were reported from wells MW-1 through MW-4 The steady and significant rise in dissolved MTBE concentrations at well MW-2 potentially indicates a vapor phase migration from the soil into the shallow ground water table Advanced GeoEnvironmental,Inc