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-32- 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 Ground Water Since the Mt. Gunnison No. 1 Mine began operations, it has experienced some mine inflows. There are three basic types of mine inflows that are seen at the mine. The first type of inflow is due to primary permeability which is ground water flow through the competent portions of F-Seam and lower Barren Member. The second type of inflow occurs in the coal seam and overlying Barren Member in areas of shallow overburden; this is secondary permeability and is the result of ground water flow through the fractured and weathered portions of these strata. The fractured rock acts as a conduit to the surface colluvial aquifer. The third type of inflow is also due to secondary permeability and it is the result of ground water flow along fault zones. These fault zones may be in contact with surface aquifers or with other water bearing zones in the overburden. The streams in the North Fork area are generally fault controlled and may be a source of recharge for fault related inflows. De-watering will occur in portions of the coal seam that contain water and in the lower portions of the Barren Member; it will reach a maximum at the furthest extent of mining. Mine inflows, on the other hand, will reach a maximum sometime before the furthest extent of mining and will then taper off until equilibrium is reached. Shallow surface aquifers located close to the coal outcrop may experience some influence by the second mechanism of mine inflow, mentioned above.