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GeoScience Services 2263 Kingston Road <br />Grand Junction, CO 81503 <br />(970) 759-6709 <br />Date: January 16, 2008 <br />Re: Acid Mine Drainage Potential at Cotter Corporation's Uranium Mines JD 6, <br />JD-8, JD-9, and SM-18 <br />The purpose of this report is to provide relevant data and technical analysis for the <br />statutory exclusion (see C.R.S. Section 34-32-103 (3.5) (b)) of the Cotter Mines JD-6, <br />JD-8, JD-9, and SM-18 (Cotter Mines) as Designated Mining Operations (DMO). C.R.S. <br />Section 34-32-103 (3.5) (b) states in part, "Such mining operations exclude operations <br />which do not use toxic or acidic chemicals in processing for purposed of extractive <br />metallurgy and which will not cause acid mine drainage." It is undisputed that the Cotter <br />Mines do not use toxic or acidic chemicals in processing for purpose of extractive <br />metallurgy. In addition, based on the analyses contained in this report, Cotter submits <br />that acid mine drainage will not occur as a result of mining operations at the Cotter <br />Mines, and that the Cotter Mines, thus, should not be considered DMOs. <br />Regulations define acid mine drainage as: <br />Contamination of water by low pH or heavy metals that occurs from mined or <br />disturbed materials as a result of the chemical and biological oxidation of reactive <br />sulfide minerals when exposed to air and water. The possibility of generating <br />"Acid Mine Drainage" exists where the pH of any exposed or potentially exposed <br />overburden, waste rock, mill tailings, waste water treatment sludge, or other <br />mined, placed, disposed or stockpiled materials has the potential to develop a pH <br />of 5.8 or less. Such determination may be based upon acceptable accelerated <br />weathering and leaching tests of a representative sample of the overburden, waste <br />rock, mill tailings, or other mined, placed, disposed, or stockpiled material. In <br />determining whether a potential for acid mine drainage generation exists, the <br />Office will consider natural pre-mining acidity and metals occurrence in bedrock, <br />soil, groundwater, and surface water where such information is available to the <br />Office. Mined and stockpiled materials does not include ore or other mined <br />product that is or will be processed within one hundred eighty (180) days of being <br />stockpiled and removed from the permit area. However, the area affected by such <br />stockpiled material may require the appropriate measures pursuant to Rules, 3, 6 <br />and 7, to prevent off-site impacts due to drainage or leaching, and for reclamation <br />of the affected stockpile area. <br />