2009-07-24_GENERAL DOCUMENTS - M2009076 (3)

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3. The Board has adopted specific regulations and DRMS has extensive experience and expertise in the area of water balance and process water containment at mineral processing facilities. 4. The Board and DRMS are designated State Dam Safety Officials for mill tailing and mine/mill process water impoundments. 5. The Board and DRMS employ regulation specific, rigorous and time tested notification and public/agency involvement in the reclamation permitting process. III. DRMS recommendation A. The Venture Resources proposal will create disturbances requiring reclamation and causing potential environmental impacts at both the extraction and mineral processing sites. Based on the proposal outlined in rough terms by Venture Resources in documents provided to DRMS, the following preliminary issues have been identified. 1. Venture Resources states that a clean and inert tailing sand will discharge from the shaker table in the proposed mill. Clean tailing through. gravity separation is a developing technology; rigorous monitoring and regulatory oversight is necessary to verify removal of sulfide minerals. Recirculation through the cleaning systems and/or sequential cleaning systems employing a variety of separation technologies are frequently required. 2. Venture Resources states that mill process water will be adjusted to a pH of 7.5 or "slightly better" and that "It is chemically impossible to have heavy metals in solution when the pH is basic." In fact, manganese and zinc, as well as other metals to a lesser extent, will remain in solution in pH neutral adjusted acid rock leachate. 3. The venture Resources proposal states that process water will be decanted from the mill tailing in the tailing impoundment and returned to the mill. Process water entrained in tailing, its decantation and management are areas that create significant environmental risk. The risk arises from embankment stability issues, water balance issues, particularly during periods of flooding, and process water containment issues. 4. Reclamation using biosolids creates a subset of environmental issues relative to availability, quality, and cost for bonding purposes. B. The Venture Resources proposal has the potential to result in net benefit to the environment, but must be sufficiently regulated for the offsetting potential for environmental degradation to be minimized. The DRMS has the authority and expertise to regulate all aspects of the proposed operations. The Board has imposed jurisdiction over comparable operations throughout its tenure under the Colorado Mined Land Reclamation Act. The DRMS recommends that the Board deny Venture Resources request for declaratory order and affirm that the re- mining of waste dumps in Colorado requires a reclamation permit.