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West Elk Mine Fork basin, a tributary to Minnesota Creek which, in turn, is tributary to the North Fork neaz `. Paonia. No portion of the Box Canyon permit revision azea is within the Dry Fork basin. All of the mining operations in the Dry Fork basin, including the Apache Rocks permit revision azea, aze covered by the augmentation plan. The augmentation plan did not become active until longwall mining first occurred in the 12N W panel (July 1998), the first panel longwall mined, within the Dry Fork drainage. The plan is based on the continuous measurement of several streams (including diversions and reservoir storage volumes) to predict the expected runoff from basins above the mining operations. The expected runoff is compared with actual measured runoff. If actual is less than expected, MCC is required to provide augmentation water as specified in the decree. A copy of the augmentation decree is provided in Exhibit 52. i` Mining in the Apache Rocks permit revision azea will not directly impact Minnesota Reservoir because the reservoir will be outside the limits of mining influence. As discussed in Section 2.05.6 (3)(b)(iii & viii), Reservoirs and Stock Ponds, MCC will maintain a very conservative setback equivalent to an angle of draw of more than 25 degreesfrom the Minnesota Reservoir dam. Surface inflows to Minnesota Reservoir are unlikely to be significantly affected based on analysis in Exhibit 52. Springs that aze within the Dry Fork basin may potentially be affected by mining to the extent that the flow is decreased, the flow moves, or dries up'. However, for the many reasons discussed herein, these flow reductions will be modest and MCC's augmentation plan assures that no downstream water users will be injured. A detailed discussion of measures taken to assess and ensure the protection of the Minnesota Creek water supply is contained in Exhibit 58, Protection of Minnesota Creek Water Supply. The Minnesota Creek water augmentation plan was predicated upon the extremely conservative assumption that all surface flows generated in the Dry Fork basin within the permit azea boundary may need to be replaced, for a total annual dry year augmentation plan requirement of up to 1,250 acre-feet per yeaz. The Apache Rocks permit revision area is approximately 20 percent of the relevant Dry Fork acreage covered by the augmentation plan. Therefore, the current augmentation plan will provide much more than adequate protection from senior water rights in the Dry Fork and Minnesota Creek basins. An important consideration relative to North Fork depletions is that, due to the regional dip of the bedding planes, inflows from streams, springs, and/or groundwater which enters the mine workings from the Dry Fork watershed could ultimately be discharged into the North Fork, rather than the Dry Fork. The 1981 Minnesota Creek Protection Plan (Exhibit 58) requires MCC to return any waters from the Dry Fork that enter the mine workings back to the basin. Due to the conservative nature of the water augmentationplan (Exhibit 52), the potential loss of these waters from the Dry Fork basin is of no consequence to downstream vested water rights as they are fully protected. 1 Flow from some springs never reaches a tributary stream because it is consumed by vegeta[ioq evaporates or infiltrates. Reduced flow from [here springs may not affect the Flow of the basin's streams. 2.05-169 RevisedJun.1995PR06:ReviudNov.19987880;t/98PR08