Laserfiche WebLink
Notably, the February 7, 2006 GeoScience report concludes at page 5 that, "In <br />summary, modeling predictions using several conservative assumptions indicated that the <br />waste piles from m'anium mining operations at the SM-18, JD-6, JD-8 and JD-9 mines pose <br />minimal impact to the environment." This GeoSciences' conclusion is based on the following <br />factors: <br />1. Model predictions show that after 1,000 years of transport, no species of concern <br />reached the undertyhig water table; <br />2. Concentrations at the leading edge of the plume are significantly lower than the <br />background concentrations in the underlying aquifers: <br />3. Even using the unrealistic asswnption of no sorption, the leading edge of the <br />plume as defined by a concentration of 1 millionth of the initial concentration fails to <br />reach the grotmdwater; <br />4. Under realistic conditions, the rock units underlying all of the mine waste pies <br />would exhibit significant sorption characteristics that would retard the movement of <br />species of concern. As noted in the response to comments, the Mon'ison Formation <br />behaves as a geochemical trap that resulted in a Uravan Mineral Belt; <br />5. Laboratory tests on the permeability of the Summerville Formation yielded a <br />hydraulic coudttctivity value of less than 9.7 E-10 cm/s effectively creating an aquichide <br />that would prevent downward tvigration of water to potential aquifers below the <br />Sununerville. For comparison purposes, concrete has a hydraulic conductivity of 1 E-8 <br />cm/s. <br />hm conclusion, the GeoSciences' report states: <br />Conservative based modeling that incorporated no sorption and relatively high <br />permeability values results in plumes that failed [o reach the underlying groundwater. <br />Under wmrealistic conditions using published values of sorption and permeability such as <br />laboratory tests for the Sununerville Formation, then there is no viable pathway for <br />species of concern from the mining waste piles to reach regional groundwater resources. <br />III. CONCLUSION <br />Cotter has demonstrated that the 7D-6 and JD-8 Mines are both dry mines which should <br />receive the same exemption which the Division provided to the SM-18 Mine. The mines may <br />12 <br />