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The potential effects of MCC's water diversion on North Fork flows <br /> have been projected for flow rates and flow volumes. With the existing <br /> pump capacity, 450 gallons per minute (gpm), the diversion would result <br /> in a measurable change in flow during low flows having return periods of <br /> about 200 years or greater, and would be less than 5 percent. During <br /> extreme low flow periods, MCC's water rights would be out of priority <br /> and diversion would not be undertaken. <br /> Although subsidence fractures that develop over and next to mine <br /> workings have the potential to dewater streams and ponds, Section <br /> 2.05.6(6) of the permit application explains that dewatering is unlikely to <br /> occur because subsidence cracks that develop at the surface will not <br /> extend deep enough to intersect fractures propagating upward from the <br /> caved and fractured zones. Also, the stratigraphic sequence in stream <br /> valleys is resistant to fracturing due to the presence of interbedded fine- <br /> grained units. These beds would more likely undergo ductile <br /> deformation(bed bending), rather than brittle deformation(bed <br /> fracturing). Stream flows and local channel elevations will continue to <br /> be monitored in the permit area, as set forth in the permit application. <br /> Subsidence magnitudes of stock ponds will also be monitored. Specific <br /> measures MCC will employ for assessing and protecting the Minnesota <br /> Creek water supply are described in Exhibit 58 of the permit application <br /> titled, "Protection of Minnesota Creek Water Supply." Possible <br /> subsidence impacts to streams and ponds are discussed in the following <br /> Subsidence Control section. <br /> Underground mine workings will come within 800 ft. of the Monument <br /> Dam and Minnesota Reservoir. MCC explains in Section 2.05.6(6) of <br /> the permit application that the reservoir is unlikely to be affected by <br /> mining because the dam and reservoir are outside the predicted angle of <br /> draw and a subsidence control plan will be implemented for mitigating <br /> possible impacts from mining-induced seismicity. (Possible subsidence <br /> impacts to the dam and reservoir and mitigation measures are described <br /> in the following discussion of the subsidence control plan.). <br /> MCC's surface water monitoring plan is described in Exhibit 71 for the <br /> South of Divide and Dry Fork lease areas, in Exhibit 71 a for the Sunset <br /> Trails area, and in Section 2.04 of the permit application for other areas. <br /> As of late 2008, MCC monitors surface water quantity and quality at 22 <br /> stream stations, comprised of 10 stations with continuous recording and <br /> 12 stations with instantaneous recording. A minimum of one year of <br /> monthly baseline data has been collected on all streams prior to mining in <br /> a watershed <br /> 3. Summary and Findings <br /> The Division has reviewed the Probable Hydrologic Consequences due to <br /> 48 <br />