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-31- Uuring the period May through September, the amount of precipitation which falls upon the watershed is less than the potential amount of water lost to evapotranspiration (PET). In other words, transpiration by native vegetation and evaporation consumes most of the precipitation and also will remove water from the soil profile. For those areas where cash crops such as apples, peaches, and the like are grown, irrigation water is removed from the North Fork of the Gunnison River and applied on such lands. Surface water in the general area is dominated by the North Fork of the Gunnison River. Flow records exist for a U.S.G.S. Gaging Station near Somerset. Data from this station (Table 2) show inflows to the area and releases from Paonia Reservoir. Outflow from the basin is not as easily determined. For example, the nearest station to Paonia is located on the Gunnison River near Lazear, Colorado, 11 miles southwest of Paonia. Such a station is too far from the study area to be acceptable for this analysis since many inflows and outflows occur between Paonia and Lazear. However, a review of past U.S. Geological Survey (U.S.G.S.) records indicates that for the years 1922 through 1932, a gaging station existed on the North Fork of the Gunnison River near Paonia. Also, for the years 1932 through 1950, a gaging station existed in Somerset. These two stations are important since Paonia Reservoir was not yet constructed and, thus, did not affect inflows to the basin. Use of these stations allows determination of approximate inflows to the North Fork of the Gunnison River contributed by the study watershed boundary located on Figure 1. The average monthly flows are illustrated on Table 2, along with the inflows to the North Fork of the Gunnison River from Minnesota Creek. These figures were used to determine the amount of outflow via the North Fork of the Gunnison River from the basin. Obviously, such predictions are not absolutely accurate. For example, less than 3 years of data existed for Minnesota Creek and 1 year (1977) experienced drought conditions. However, for purposes of this assessment, such figures provide a rough approximation of flows through the general area. PROBABLE HYDROLOGIC CONSEQUENCES OF THE HAWK'S NEST MINE Ground Water The potential aquifers which may be affected by the Hawk's Nest Mine are the alluvium of the North Fork of the Gunnison, the Rollins sandstone and the lenticular sandstones located stratigraphically above the mine. The most significant aquifer in the permit and hydrologically adjacent areas is the alluvium of the North Fork of the Gunnison. Ground water pumped from wells completed in the North Fork alluvium supplies domestic, agricultural and industrial uses. The Hawk's Nest Mine is not presently impacting the quantity of water in the North Fork alluvium. The Hawk's Nest Mine workings will not extend under the North Fork alluvium. The First East Mains in the "E" seam parallel the North Fork and extend below the elevation of the river and its alluvium. These mains are dry, indicating that the "E" coal seam and its associated roof and floor strata are not aquifers. Therefore, the Hawk's Nest mining operation is not depleting the quantity of ground water in the alluvium through mine induced inflows.