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' 08 June 2005 AGE-NC Project No. 95-0137 ' Page 6 of 6 ' • Target analytes were not detected in soil samples collected from pilot borings MW9 and MW10. The lateral extent of petroleum hydrocarbon-impacted soil is defined; the vertical extent of petroleum hydrocarbon-impacted soil is defined in the vicinity of former UST area. • The ground water depth increased 1.3 feet between the first and second 2005 quarterly ground water monitoring events. The ground water flow direction was inferred to be northwest at a low hydraulic gradient west of well MW-1 and the former UST release area. • Dissolved petroleum hydrocarbon concentrations on-site and directly down-gradient of the r former UST area, were below detection limits in second quarter 2005. ' • Dissolved 1,2-DCA concentrations generally have been declining. 1,2-DCA has not been detected in well MW-2 for three consecutive quarters and well MW-1 for four consecutive ' quarters.However,the concentrations in well MW-4,MW-9 and MW-10 remain significant, are currently undefined by the monitoring well network and are above the DHS' Maximum Contaminant Level (MCL) of 0.5 µg/l in drinking water. The lateral extent of dissolved 1,2-DCA is undefined west and down-gradi�nt of the site, beyond the recently installed ground water monitoring wells. 5.0. RECOMMENDATIONS Based on the findings of the environmental activities recounted in this report and previous investigations, AGE recommends: ' Continuation of the quarterly ground water monitoring program;the next monitoring event is scheduled for August 2005. 1 6.0. LIMITATIONS Our professional services were performed using that degree of care and skill ordinarily exercised by environmental consultants practicing in this or similar localities. The findings were based upon analytical results provided by an independent laboratory.Evaluation of the hydrogeologic conditions at the site for the purpose of this investigation was made from a limited number of available data points (e.g., soil and ground water samples) and subsurface conditions may vary away from these data points.No other warranty, expressed or implied, is made as to the professional interpretations, opinions, and recommendations contained in this report. Advanced GcoEnvironmental,Inc.