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minimalist approach to proving through SPLP tests that the tailings will not introduce acid and <br />contaminants into the Sneffels Creek watershed. <br />Likewise, the assertion that the waste rock will naturally be inert and free of mineralized <br />vein material, and therefore also free of care in its disposal, should be scrutinized. First, the <br />applicant proposes that the majority of waste rock generated at the mine -- approximately 20,000 <br />tons annually -- will mostly be sold or given to Ouray County; if this arrangement should not <br />come to fruition, what will become of the waste rock? In addition, because the applicant asserts <br />that the waste rock bears no vein material, they propose that it not be tested at all (Exhibit T page <br />14; page 37). A testing protocol should be established, and an SPLP test should be performed on <br />the waste rock at minimum once a year. <br />The hydrology of the Revenue Mine appears to be complex and Star Mine Operations has <br />done an extensive job monitoring water quality from sampling locations both inside and outside <br />the mine and is in the process of receiving state discharge permits for the release up to 2,000 <br />gallons per minute, a substantial amount of water. Inside the mine, they have identified the Atlas <br />drift as contributing the lion's share of zinc into the mine discharge, which may or may not <br />require additional treatment in order to meet state permitting standards. Despite the water <br />monitoring that has already been done, however, questions remain about why water quality <br />changes as flows travel toward the mine portal. Star Mine Operations suggests that there is a <br />natural reduction in zinc levels but notes in Exhibit T at page 6 that "none of the data available <br />shows exactly why the zinc levels are dropping in both the mine water channel and in Sneffels <br />Creek but it shows that the zinc levels do drop over time and distance." While the natural <br />precipitation of zinc from organic material now present in the mine may be helping this <br />phenomenon, it hasn't been clearly determined in the water analysis and data submitted. <br />Activities in the mine will obviously alter the presence of organic material that may be <br />contributing to zinc precipitation. While the applicant suggests that natural precipitation in the <br />underground workings may be encouraged with the placement of magnesium -rich rocks and <br />other organic material, there is no specificity to this regime. Over time, this method may prove <br />unreliable. More water quality data and a better understanding of the hydrology is needed to <br />determine the best plan of action for treating mine water. <br />Star Mines suggests that it may consider sealing the Atlas drift inside the mine in order to <br />reduce infiltration of zinc - tainted waters into the Revenue's portal discharge (Exhibit T, page 7.) <br />This idea should be more thoroughly vetted. Sealing a drift is a temporary measure at best, as <br />nothing can beat the determination of water to flow downhill. Additionally, sealing drifts in one <br />mine could have unforeseen consequences to the hydrology and stability of adjacent mines, and <br />the Revenue has several close neighbors. <br />The applicant also acknowledges that high- alpine wetlands will be impacted by mining <br />operations and that a 404 permit from the Army Corps of Engineers may be required (Exhibit T <br />page 19). Because of this likelihood, the Division should consider the Corps' consultation once <br />