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Given these considerations, Cotter proposes the following course of action (versus <br />immediate direct treatment of mine pool water): <br />1. Immediately begin treating all surface or groundwater that reports to Sump One. <br />2. Relocate the current water treatment discharge point to one that maximizes <br />beneficial impacts of releasing treated water to the creek, and improves the <br />overall effectiveness of treating contaminated water (by preventing recirculation <br />of treated water through the alluvial fill). <br />3. Analyze representative samples of source term material from the alluvial fill to <br />verify that it would not create acid or toxic forming issues if disposed of in the <br />Minnesota adit underground disposal area. Resume 2010 plans to excavate and <br />dispose of alluvial fill source term material in the Minnesota adit. This disposal <br />practice was previously approved for "inert" materials by DRMS in Technical <br />Revisions 4, 6, and 10 and small amounts of "natural uranium ore" were included <br />in two of those Technical Revisions. Mining waste rock and associated residuals <br />in the alluvial fill, believed to be the primary cause of impacts to water quality in <br />Ralston Creek should qualify for underground disposal in the mine from which <br />they originated. This would remove and isolate such material from exposure to <br />pervasive environmental cycles of oxidation and groundwater leaching in the <br />shallow alluvial fill, reducing or eliminating existing contaminant migration <br />pathways to Ralston Creek. <br />4. Increase the frequency and number of water quality monitoring stations to assess <br />any further targeted action as needed to meet water quality standards in Ralston <br />Creek. <br />3. Detailed financial warranty provisions for the plans must be included with the <br />Technical Revision application. <br />Response to 43 <br />Cotter and DRMS staffs have agreed that the financial warranty at this point will project <br />costs for water treatment plant installation, operation and maintenance through December <br />31, 2010. Shown below are those costs: <br />Rate Total Type <br />$ 5,788 $ 150,488 Weekly rental of treatment equipment <br /> $ 107,115 Lump sum mobilization/demobilization <br />$ 3,355 $ 87,230 Weekly operations <br />$ 240 $ 31,200 24 week cycle resin disposal <br /> $ 2,500 Shipping resin disposal <br /> Purchase new resin, load. Prepare & <br /> $ 66,880 package old resin for shipping <br />Total: $ 445,413