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area water resources. It should be recognized that the mine-water is a <br />reflection of groundwater contact with mined materials which is <br />comprised of exposed rock faces, broken and crushed rock from the <br />mining activity. If the mined-materials leant soluble constituents of <br />concern, elevated concentrations of these constituents would be <br />observable in the water, and in extraction analysis of the solids (further <br />described in item 2 below and Attachment 1). The character of the <br />mine-water demonstrates water quality with a basic ph (-8) with low <br />concentrations of naturally occurring metals. <br />2) Solids analysis of leachable toxic elements has been accomplished by <br />the previous operator, and by the current permit manager. The design <br />of sample collection and analysis requirements were requested by Kate <br />Pickford/DRMS/Durango office which specified that a sample of tailings, <br />ore and waste rock be collected and analyzed for a defined suite of <br />constituents using the synthetic precipitate leachate procedure (SPLP) <br />(refer to correspondence documented by K. Pickford/2008). Additional <br />samples of waste rock were collected to provide a more robust data set <br />describing the mined materials. An initial interpretation of these results <br />was provided to DRMS, and the DRMS Geochemist (David Bird) <br />provided comments (Bird, 2010). The report was therefore revised to <br />accommodate these comments. The document (provided in <br />Attachment C.1) provides a comprehensive discussion of the solids <br />geochemical analysis pertinent to this exhibit. Results indicate that the <br />mined materials from the Ruby Trust are inert (not acid forming). In the <br />absence of 'acid', toxic-forming constituents (i.e. metals) are relatively <br />insoluble. Further analysis using SPLP extraction methods indicate that <br />detected metals occur at concentrations below EPA solid waste <br />thresholds which define toxicity limits. Comparison of the SPLP leachate <br />results to State of Colorado thresholds protective of groundwater <br />indicate there few constituents of concern. Further analysis of this <br />information is provided in Attachment C.1. <br />3) The majority of the mine-water is actively managed in order to be able <br />to mine. As a result, the majority of the mine-water is released under <br />the CDPS permitted discharge which controls water quality impacts as a <br />permit requirement. Any remaining water left in place could solubilize <br />constituents of concern from mined-materials however, the character <br />of the water is slightly 'basic' which does not tend to solubilize most <br />metals (Williams and Schuman, 1987). Acidic settings cause constituent <br />solubilization due to competitive solubility with hydrogen ions from <br />4