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in waste rock facilities, duration of exposure to weathering, and reclamation and closure techniques. In 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-9 Mine. A similar evaluation was presented to the Division on the same date for the JD-9 Mine. After a thorough evaluation, GeoScience Services concluded with regard to both mines that: 6.0 Conclusions and Recommendations Numerical modeling studies of the h'ansport of constituents of concern from the waste track pile (or temporary ore storage piles) at the SM-1S Mine and applied to the JD-9 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. In addition, for the 1,000 yeaz 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 tithe. The net result is a model that over predicted the amount and availability of constituents of concern for transport. Even using such conservative assumptions, results of the modeling simulations showed that no contaminatimt reached the uuderlying groundwater system. For all of the analytes tested, none will migrate through the Brushy Basin 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 Sandstone. [Emphasis added.] In summary, mining operations at the JD-9 mine pose no signif-scant threat to the groundwater resources in the area. [Emphasis added.] The Division commented on the GeoScience October 19, 2005 reports in a January 17, 2006 letter to Cotter and stated, in part, "The evaluation procedure, which was developed mutually by the operator [i.e., Cotter Corporation and the Division] is similar to the procedures 7