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_pl_ Two reservoirs are located within the life of mine area. Minnesota Reservoir is located on Dry Fork. It has a decreed capacity of 1,285 acre-feet. The actual capacity may be closer to 500 acre-feet, however. Beaver Reservoir is located on the East Fork of Minnesota Creek and has an absolute decreed capacity of 1,620 acre-feet and a conditional decree of 552 acre-feet. Both reservoirs store water for irrigation purposes and are filled during spring runoff. They are usually drained by late August or early September. Water quality parameters for the North Fork are given in Table 3. As indicated, waters in the North Fork are a calcium bicarbonate type. There are moderate levels of sulfate. Salinity averages less than 100 mg/1. Water quality data has been collected at several sites throughout the environmental study area. The data indicate that those waters are also the calcium bicarbonate type and relatively low total dissolved solids concentrations. There are a total of 13 decreed water rights on or near the lease area. but outside the five year permit area. The applicant has determined that an additional 29 downstream rights might be affected by the life of mine project. However, since the impacts will be addressed in future permit terms, no additional analysis is needed for this permit decision. The majority of springs that migh~ be impaired are located above the "F" seam outcrop. The Mt. Gunnison No. 1 Mine is an underground mine within the F coal seam. Mining is to progress from the portals in the valley of the North Fork of the Gunnison River up the dip of the F seam under the watershed of Minnesota Creek. The extraction.of coal will be by continuous mining methods. Controlled subsidence will occur during pillaring. Development waste rock and processing waste from the Mt. Gunnison mine will be disposed of in one permanent disposal pile. Load out facilities for the Mt. Gunnison Mine are located along the North Fork of the Gunnison River. Regional Geology The Somerset Coal Field lies on the southeast margin of the Piceance Basin, and just south of Grand Mesa. The sedimentary strata exposed in the Somerset Coal Field dip at 3 to 5 degrees to the north and northeast. Only minor faulting of limited vertical displacement has been observed in the existing Blue Ribbon, Bear, and Hawk's Nest Mines. However, in the Orchard Valley Mine, a fault with a displacement of 50 feet was encountered during mining. Drill hole data indicates the presence of other faults in the .life-of-mine area with similar displacements. One ~ ~~