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operations, processed historic mine waste dumps through the mill for the primary purpose of environmental <br />clean-up as opposed to profitable recovery of metal concentrates. If the tailing samples tested by TCLP <br />were from waste dump processing, they may be much lower in metal content and acid generating potential <br />than concentrates produced by milling of ore grade vein material. <br />c. A description of representativeness of the data provided in the table titled "Flotation Tailings Water <br />Analysis, Cash Mine Dump." From the title, it appears that this was analysis of interstitial water from <br />tailing produced from milling of the Cash Mine waste dump, which may be lower in metal and metal <br />sulphides than tailings derived by milling of ore grade vein material. Even so, the water analyzed is <br />impaired by relatively high dissolved solids and by high concentrations of manganese. The manganese <br />concentration in this water is generally lower than the manganese concentrations measured in the Cash <br />Mine pool, but the dissolved solids are generally higher, which argues against permitting of tailing disposal <br />into the underground workings. <br />d. As we have discussed, DRMS will be inspecting the Gold Hill Mill and the Cash and Who Do Mines <br />permit areas, permit nos. M-1994-117 and M-1983-141 respectively, once snow cover has cleared <br />sufficiently. As part of the inspections, DRMS will be collecting samples of mill tailing for laboratory <br />analysis. In no case will DRMS consider approving disposal of tailing into mine workings until the <br />laboratory results from analysis of the samples have been returned and reviewed. <br />3. Source water for the Gold Hill Mill is of critical relevance to the consideration of disposal of mill tailing <br />into underground workings. The following issues must therefore be addressed. <br />a. The water source(s) for the Gold Hill Mill are discussed in various documents in both permits M-1994- <br />117 and M-1983-141. At the time of the original permitting of the mill and through most of the life of the <br />operation, water from Left Hand Canyon has been described as the primary water source. Certainly <br />precipitation that collects in the tailing pond has also been a water source, as has, during some periods of <br />operation, meteoric water collected in the Hazel-A adit. Whether or not these latter two sources have been <br />adjudicated for use in the mill is not specified in the DRMS permits; provide this information. At the time <br />of finalization of amendment AM-02 and submittal of technical revision TR-05 to permit no. M-1983-141 <br />in late 2006, Mount Royale Ventures indicated that Cash Mine water would become a water source for the <br />mill. Through discussions with Mount Royale Ventures, it is the understanding of the DRMS that the State <br />Engineer's Office (SEO) has since determined that Mount Royale may not use the Cash Mine water as a <br />non-tributary source. Mount Royale has stated to DRMS that SEO has given some form of temporary <br />authorization to pump limited Cash Mine water to the Gold Hill Mill tailing pond. Provide a complete <br />discussion of these SEO interactions along with any supporting documentation. <br />b. Under permit no. M-1994-117, the Gold Hill Mill is authorized to process up to 70,000 tons of ore per <br />year. If the tailing from processing that tonnage of ore were to be discharged into underground mine <br />workings, the release of water from the tailing into the mine pool would be an order of magnitude greater