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CMC Response: The Times Mine adit portal is located at an elevation of 8,355 feet and the <br /> elevation of the collar of the fifty (50) foot winze is approximately 8,360 feet. The Wynona Mine <br /> shaft is collared at an elevation of 8,445 feet and the maximum elevation that water will be <br /> retained in this mine is 8,360 feet this parameter was incorporated into the bulkhead design by <br /> Louis W. Cope, the Colorado Registered Professional Engineer. However, milling operations <br /> water demand would provide a constant draw-down on the stored water level in the Times and <br /> Wynona Mines. The only time that the water level would rise above the collar of the internal <br /> winze connecting the Times Mine with the Wynona Mine would be when full replenishment is <br /> accomplished by pumping from of the Left Hand Creek Pumping Station. Given the distance and <br /> the rise in elevation between the location of the Bean pump and the Times Mine Bulkhead, it is <br /> very unlikely that the pump selected for this project could pump more water into the Times Mine <br /> than the amount that would be present in the Times Mine Cross-cut under these parameters. The <br /> water levels will be monitored by periodic manual measurements in the Wynona Mine shaft well <br /> casing. <br /> 13) The operator's response to item no. 24 states the Times Mine still retains water from <br /> the last period when water was pumped behind the bulkhead. Does the operator have any <br /> idea of current water levels in the workings? Does the operator have any way to collect <br /> water quality samples from the existing mine-pool? <br /> CMC Response: When the Times Mine bulkhead was last examined in September 2018, the <br /> water level behind the bulkhead was above the bottom of the three (3) inch PVC pipe shown on <br /> the drawing of the bulkhead. Anyone of the three PVC pipes could be used to collect water <br /> quality samples from the existing mine-pool, since, as the drawing indicates, there are ball valves <br /> on each of the PVC pipes, and they can be opened and closed from this side of the bulkhead. <br /> 14) In accordance with a previous permit commitment made by the operator, once the operation <br /> begins storing water in the Wynona Mine, the operator will commence sampling at that location. <br /> Therefore,please submit a water quality sampling plan for the Wynona Mine. <br /> CMC Response: The Wynona Mine water will be sampled on a quarterly basis when the <br /> operation begins storing water in the mine and when the Gold Hill Mill is in operation. It will be <br /> sampled for the same parameters in mg/1 (T) as it was previously when the mill was being <br /> operated, with the following elements: Arsenic, Cadmium, Copper, Iron, Lead, Mercury, Silver <br /> and Zinc, along with pH, Solids (dissolved), and Sulfate as 5O4, mg/l. <br /> 15) The operator's response to item no. 25 states that operating at 50 tons per day for 260 days <br /> per year and at 4 tons of water per ton of ore processed would result in the removal of 1,651,000 <br /> gallons of water per year. The operator states this amount is well below the maximum volume of <br /> water that could be withdrawn from Left Hand Creek during irrigation season, which is <br /> 3,388,850 gallons of water. Please clarify the conversion factor that was used to determine the <br /> 8 <br />