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1 - KLEIh1FELDEft ' 6 CONCLUSIONS AND RECOMMENDATIONS ' Kleinfelder has completed the second semi-annual groundwater monitoring for 2007. On October 17 and 28, 2007, seven monitoring wells (MW-1 r, MW-2r, MW-5, MW-6r, MW-25, MW-26, and MW-27) were sounded, purged and sampled. Groundwater ' samples obtained from each location were submitted for chemical analysis including the following; pH, TDS, total alkalinity (including the alkalinity series), chloride, nitrate as N, sulfate, specific conductance, calcium, and sodium. ' Based on the data obtained during this semi-annual monitoring event and historical sampling events, the following conclusions have been formulated: ' 1. The depth to groundwater during the second semi-annual 2007 sampling event ranged from 16.04 to 23.12 BTOC. The corresponding groundwater ' elevations at the site ranged from 18.38 to 26.23 feet msl. Groundwater gradient at the site was estimated to be 0.002 ft/ft to the northwest. The groundwater elevations, flow direction and gradient were consistent with previous findings. 2. The concentrations of the requested analytes appear to indicate generally ' 'hard water' conditions to be present in the sample locations, including upgradient well MW-5. In general, the highest concentrations of analytes appear to be in the wells adjacent and downgradient to the former locations 1 of the lime ponds (MW-1 r and MW-2r) and in the down gradient wells MW-25 and MW-26. ' 3. The results the second semi-annual 2007 sampling event were generally consistent with previous results and indicate a generally decreasing, or stabilized, trend of concentrations of the primary analytes over time in each of the wells. In general, the concentrations of the analytes in the monitoring locations downgradient of the former lime pond continue to be below both the initial and the highest concentrations detected in each of those wells during past sampling events. One exception is an increasing trend in bicarbonate alkalinity noted in MW-25. Due to the redevelopment of the former lime pond area for industrial use, decreased onsite recharge is expected to lessen the leaching of soluble analytes present. It is Kleinfelder's opinion that the conditions will result in a continued decrease in concentrations of the ' "constituents of concern" with time. Kleinfelder expects general shallow groundwater quality to continue to improve over time. ' 4. The concentrations of TDS, bicarbonate alkalinity, and EC in each of the monitoring locations have reached levels below the highest recorded concentrations of those analytes in the background well MW-5. Thus, the ' 20-3978-03.MN71ST08Ri 17 February i,2008 ®2008 Kleinfelder Page 16 of 19 1