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-24- at fresh cut faces, while mine entry walls a short distance from the face were dry. The sandstone and siltstone roof strata in the Blue Ribbon, Hawk's Nest and Somerset mines also weep for short periods of time following mining and eventually dry up. The Hawk's Nest Mine workings in the "E" seam are dry even though these workings are within 600 feet of the North Fork, are below the level of the North Fork, and are parallel to the North Fork. These in-mine observations indicate that the "B-2", "E" and "F" coal seams and their roof strata are not significant regional aquifers. Observations of mining within the "C" seam at the Bear No. 1 and No. 2 mines and of mining within the "D" seam at the Orchard Valley Mine indicate that the "C" and "D" seams and their associated roof strata also are not significant regional aquifers. If the coals and their roof strata were aquifers, these strata would have continued to weep throughout the life of these mines. Some fractures and faults transect the Mesaverde Formation and extend vertically to the surface. These faults and fractures produce narrow bands of secondary porosity within the rock strata. Due to the low permeability of the rock strata within the Mesaverde Formation, these faults and fractures provide the primary path through which water flows both vertically between rock strata and horizontally within rock strata. When faults and fractures are encountered within the mines in the North Fork region, they generally produce mine inflows. The flow characteristics of each mine inflow associated with faults and fractures depend upon the lateral extent and the proximity of the fault or fracture to a stream valley. All inflows from these sources are characterized by an initial surge of water which then either decreases, or ceases completely with time. Since most stream channels in the North Fork drainage basin are developed in zones of weak fractured rock associated with fracturing and faulting (Dunrud, 1976), mine inflows from fractures and faults below these streams mimic the temporal flow characteristics of the overlying streams. In Hawk's Nest Mine, an inflow was encountered under the ephemeral drainage of Hawk's Nest Creek. The rates of inflow beneath this drainage fluctuate seasonally with a slight lag time in response to the flows in the overlying stream, In the Somerset Mine and Blue Ribbon, inflows beneath and adjacent to Hubbard Creek are continuous and reflect the perennial nature of this stream. To date, the Orchard Valley Mine has experienced minimal inflows of around 200 gallons per day. This inflow came from both the floor and roof and were generally roof drips or wet areas on the floor. No major drainages have been crossed which may increase significantly the amount of inflows this mine'is experiencing. Inflows from faults and fractures located outside stream valleys (such as in the Orchard Valley Mine) generally dry up with time or flow intermittently at discrete points along the fault or fracture. Those which continue to flow have flow rates which diminish to a trickle. Such inflows may represent the dewatering of lenticular sandstone units with limited recharge areas, or may represent flows through fracture zones extending to the surface which have narro~ recharge zones on steep slopes.