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Requirement 1: Cotter will investigate and characterize any solid source term materials residing <br />within the Pad adjacent to the former mine workings that may contribute to exceedances of <br />groundwater or surface water quality standards. Cotter will provide a written summary of the <br />findings, along with a plan and schedule for containment or removal of such solid source term <br />materials. <br />Response: <br />A thorough investigation of solid source term materials within the Pad has been <br />completed in accordance with a study plan approved by the Division of Reclamation, <br />Mining and Safety (DRMS) under Technical Revision 14 (TR -14) to the mine <br />reclamation permit (permit M- 1977 -300). A detailed report of the findings of the <br />investigation is provided as Attachment 1 to this submittal. <br />Pending approval by DRMS, the plan for remediation of solid source materials within the <br />Pad includes removal and disposal in an onsite repository. As detailed and assessed in <br />the report for TR -14 (Attachment 1), options for onsite disposal include placement within <br />the abandoned underground mine workings or within an engineered above ground waste <br />rock repository. Selection of the most appropriate disposal option(s) will be pursued with <br />DRMS through a technical revision or amendment to the mine reclamation pen <br />The current schedule to initiate remediation of source term materials within the Pad is in <br />late summer or fall of 2012. This timing is governed by the need to sufficiently dewater <br />the Pad, which is expected to be achieved for about five months in 2012 once a creek <br />diversion pipeline is in place and annual spring runoff has subsided to the point where <br />flow in Ralston Creek has remained below diversion capacity for several weeks. <br />It is not anticipated that all solid source term materials within the Pad that exceed the <br />cleanup standard developed in TR -14 (7 pCi /g radium -226) can be removed in 2012. In <br />addition, if an engineered above ground repository is selected and approved for disposal <br />of this material, the design and permitting process could present additional challenges in <br />the Pad remediation schedule. <br />Given the above considerations, the most aggressive schedule that can realistically be <br />achieved for removal of all solid source term materials within the Pad that exceed the <br />cleanup standard is likely to be sometime in the fourth quarter of 2013. <br />Requirement 2: Cotter will investigate the waste rock piles and assess any related contributions <br />to exceedances of groundwater or surface water quality standards at the Site. Cotter will provide <br />a written summary of the findings, along with a plan and schedule for mitigation of any such <br />impacts. <br />Response: <br />Cotter has reviewed historical assessments of potential impacts from waste rock piles <br />( "WRPs ") and has carefully analyzed decades of water quality data from monitoring <br />2 <br />