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Minnesota and Beaver Reservoirs are both located below the outcrop <br /> of the F Seam coal. These reservoirs are used to store water for <br /> irrigation and will not be directly affected by mining the F Seam. The <br /> portions of lower coal seams under the reservoirs, inLuding the E and <br /> B Seams, are legally severed from the lease. <br /> Sevend springs that feed into Minnesota Creek could be affected by <br /> mining; to the extent that the flow is decreased or that they completely <br /> dry out. Generally, it is not expected that the flow in Minnesota <br /> Creek will be decreased significantly as a result of mining the F <br /> Seam. During the next five-year permit term, no mining will take <br /> place south of the Minnesota Creek Basin drainage divide with the <br /> exception of a small area adjacent to the divide where the B Seam <br /> main entries will be located. It is expected that these main entries will <br /> not impact the hydrologic balance of the Minnesota Creek Basin. A <br /> detailed discussion of measures taken to assess and ensure the protec- <br /> tion of the Minnesota Creek water supply is contained in Exhibit 58 of <br /> the permit application entitled, "Protection of Minnesota Creek Water <br /> Supply." <br /> During; Water Year 1982, the conditional right to withdraw water <br /> from the North Fork was deemed absolute. When this water right is <br /> in priority, water can be pumped from the intake point to the <br /> freshwater pond. This water right is expected to be out of priority <br /> from July to September. <br /> The freshwater pond (FW-1) has a ten acre-foot capacity. Average <br /> withdrawals from the North Fork of the Gunnison are not expected to <br /> exceed 400,000 gallons per day (gpd) during the term of the permit <br /> and are likely to be on the order of 200,000 gpd. The freshwater <br /> pond is filled during spring runoff and kept full until water rights are <br /> out of priority. The water is either treated to meet potable and <br /> sanitary water requirements, used and then treated as sanitary waste <br /> water, or withdrawn for dust suppression in the mine and becomes <br /> mine water. <br /> The potential effects of this water diversion on North Fork flows are <br /> developed for both flow rates and flow volumes. With the existing <br /> pump capacity, 450 gallons per minute (gpm), this diversion would <br /> result in a measurable change in flow for low flows with return <br /> periods of about 200 years or greater. Additionally, during the <br /> extreme low flow periods, MCC's water rights would be out of <br /> priority and diversion would not be undertaken. <br /> It is presumed that any change in flow that is less than five percent <br /> and within the measurement error of a stream gauge would not result <br /> in a hydrologic impact. Table 4 of this document shows the estimated <br /> 36 <br />