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I 04 March 2002 i AGE-NC Project No 96-0249 ' Page 4 of 6 ' Laboratory analysis of the sample collected from domestic drinking water well DW-1 did not detect any constituents of concern above laboratory reporting limits, however, MTBE was detected from the RDW-1 sample at a concentration of 13 µg/l (EPA 8260) Previous and current analytical results of ground water monitoring well samples are summarized in Tables 2 and 3, analytical results of the ground water samples collected from the domestic drinking ' water wells DW-1 and RDW-1 are summarized in Table 4 The laboratory reports (McCampbell Analytical Inc I D No 86090 through 86095) and chain-of-custody forms are presented in Appendix C 4.0. SUMMARY AND CONCLUSIONS The implications from the December 2001 ground water monitoring event are as follows ' Ground water flow direction for the area bound by Three B's Truck Plaza wells MW-1 through MW-6 was inferred to be toward the east at a gradient of 0 001 ft/ft, or approximately 5 feet per mile and less (Figure 3) Due to the low 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 Ground water flow direction at the site may have been influenced by pumping of either the ' Rocky's Restaurant and/or the Three B's Truck Plaza domestic drinking water wells • The ground water elevation at the site was within the screened intervals of wells MW-1 through MW-6 which should yield samples fully representative of shallow ground water conditions • Ground water elevation at the site increased an average 2 89 feet between the September ' 2001 and the December 2001 ground water monitoring events (Table 1) • The lateral extent of the dissolved petroleum hydrocarbon plume is not known toward the south, southwest, west, northwest, north and northeast of the area bound by wells MW-1 through MW-6, the vertical extent on the site is not known(Figures 4, 5, 6 and 7) • The elevated petroleum hydrocarbon concentrations detected in water samples collected from wells MW-1, MW-2, MW-3 (screened between 5 and 25 feet bsg) suggest that these wells may be screened within or near a "core area" of a dissolved petroleum hydrocarbon plume However, the area of greatest dissolved petroleum hydrocarbon-impact was encountered in ' the samples from wells MW-3 and MW-6 (Figure 4) Lower petroleum hydrocarbon concentrations were detected from intermediate well MW-1 which may indicate a separate IAdvanced CeoEnvironmental,Inc