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West Elk Mine Canyon permit revision area is within the Dry Fork basin. All of the mining operations in the Dry Fork basin are covered by the augmentation plan. The augmentation plan did not become active until longwall mining fast occurred in the 12NW 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 compazed with actual measured ntnoff. 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. The Dry Fork basin has a very low yield. In fact, for water administration purposes, the water commissioner does not attribute any water exiting by Dry Fork as native flow produced by the basin. Rather the Dry Fork channel serves as an extension of the Deep Creek Ditch, which diverts water from Little Gunnison Creek and traverses Deep Creek prior to dumping into the headwaters of Dry Fork. The Deep Creek Ditch conveys irrigation water into Dry Fork for storage and release to downstream ranches along Minnesota Creek. The ditch typically diverts from May through July, with average annual diversions of 772 acre-feet based on SEO diversion records for 1970 to 2002. As discussed previously, there is little chance that mining will affect the Dry Fork channel Consequently, it is unlikely that transbasin diversion from the Deep Creek Ditch will be disrupted by mining subsidence. However, MCC will monitor streamflows and channel conditions so that any potential impacts can be discovered quickly and mitigated as described in the Minnesota Creek Protection Plan. Mining in the South of Divide perrnit revision azea will not duectly impact Minnesota Reservoir because the reservoir will be outside the limits of mining influence. As discussed in Section 2.05.6 (3)(b)(iu & viii), Reservoirs and Stock Ponds, MCC will maintain a very conservative setback equivalent to an angle of draw of more than 25 degrees from the Minnesota Reservoir dam. Surface inflows to Minnesota Reservoir aze unlikely to be significantly affected based on analysis in Exhibit 52. Springs that are within the Dry Fork basin may potentially be affected by mining to the extent that the flow is decreased, the flow moves, or the spring(s) dries up. It should be noted that flow from some springs never reaches a tributary stream because it is consumed by vegetation, evaporates or infiltrates. Reduced flow from these springs may not affect the flow of the basin's streams. 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. In addition, the only decreed spring (Deer Creek Domestic Springs Pipeline) within the South of Divide permit area is owned by MCC. 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 pemut area boundary may need to be replaced, for a total annual dry yeaz augmentation plan requirement of up to 1,250 acre-feet per yeaz. The South of Divide pernut revision area is approximately 70 percent of the 1.05-176 Revised Ju~re 1005 PRl0