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hi the normal course, the Division carefully evaluates the proximity of ore and waste rock piles to surface and ground. water resources. This analysis is typically based on site-specific examinations [hat consider the proximity to streams, and ground water, as well as the size of ore in waste rock facilities, duration of exposure to weathering, and reclamation and closure techniques. hi response to questions raised by the Division, and on behalf of Cotter, GeoScience Services presented an October 19, 2005 report to the Division entitled "Evaluation of Potential Contaminant Migration for Uranium Mining Operation at the JD-6 Mine. A similar evaluation was presented to the Division on the sanie date for the JD-8 Mine. After a thorough evaluation, GeoScience Services concluded with regard to both mines that: 6.0 Conclusions and Recommendations Numerical modeling studies of the transport of constituents of concern from the waste tack pile (or temporary ore storage piles) at the SM-18 Mine and applied to the JD-6 Mine [and JD-8 Mine] indicate that the pile poses no significant threat to underlying groundwater resources. The flow and transport model incorporated several conservative assumptions regarding the hydraulic and geochemical parameters. Most conservative was the assumption that the pore-water in the waste pile contained constituents of concern concentrations that reflected SPLP test conditions. Actual rainwater exhibits a higher pH value (less acidic than SPLP leaching fluid) and would leach constituents of concern at lower concentrations. hr addition, for the 1,000 year simulation, concentration of constituents of concern in the waste-rock pore water were maintained at initial concentrations. In reality, as constituents of concern are leached from the waste rock, concentrations would steadily decline in time. The net result is a model that over predicted the amount and availability of constituents of concern for transpm•t. Even using such conservative assumptions, results of the modeling simulations showed that no contamination reached the underlying groundwater system. For all of the analytes tested, none will migrate through the Salt Wash Member of the Morrison Formation. The Summerville Formation provides an additional barrier preventing the constituents of concern from impacting the groundwater in the underlying Entrada Sandstrone. [Emphasis added.] In summary, mining operations of the JD-6 mine [and the JD-S mine) poses no significant threat to the groundwater resources in the area. [Emphasis added.] 8