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The total maximum streamflow for the North Fork of the Gunnison River <br />depletion at the Bear No. 3 Mine is estimated to be about 1,721,000 <br />gallons or 5.3 AC-FT per year. <br />WATER CONSUMPTION DETAILS <br />Mining <br />. <br />The primary utilization of water, from the shallow well is for dust 1 <br />suppression at underground coal mining operations in the Bear No. 3 <br />Mine. During mining and haulage to the loadout the moisture content of <br />the coal generally increases by about 2%. With an average annual <br />production rate of 275,000 tons, mining consumes approximately 1,180,000 <br />gallons of water each year. <br />Ventilation <br />• The Bear Coal Company is located in a region of low relative humidity. <br />It is apparent that the air ventilated through the mine has higher <br />relative humidity when leaving than when entering. Therefore, some <br />water used for dust suppression evaporates and is lost through <br />ventilation. Bear Coal has estimated this loss to be about 160,000 <br />gallons per year. <br />Mine Inflows and Outflows <br />No mine ground water inflows have been encountered at the Bear No. 3 <br />Mine. Although perched water systems are known to exist and may be <br />encountered during mining, the depletion of streamflow is negligible. <br />Sediment Pond Evaporation <br />The sediment pond currently in place at the Bear No. 3 Mine has a <br />capacity of 1.5 AC-FT. The purpose of the pond is to contain surface <br />runoff from the surface facilities area. The water is held for a short <br />period of time, less than 72 hours, to allow for settling and is then <br />-3- <br />