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of the Barren member have water levels that vary <br /> greatly. This may indicate the discontinuity of the <br /> water bearing strata. Generally, springs in the permit <br /> area seem to act independently of the bedrock water <br /> leasing zones and appear to be surface features related <br /> to weathered and fractured bedrock. Flow from these <br /> springs tend to be highly ephemeral and only discharge <br /> during spring snow melt. These springs recharge and <br /> discharge in relatively small areas. <br /> Inflows from faults and fractures located outside <br /> stream valleys (such as in the Orchard Valley Mine) <br /> generally dry up with time or flow intermittently at <br /> discrete points along the fault or fracture. Those <br /> which continue to flow have flow rates which diminish <br /> to a trickle. Such inflows may represent the <br /> dewatering of lenticular sandstone units with limited <br /> recharge areas, or may represent flows through fracture <br /> zones extending to the surface which have narrow <br /> recharge zones on steep slopes. <br /> Discharge of ground water occurs through numerous seeps <br /> and springs . Over 100 springs are located in the <br /> life-of-mine area. The locations of these springs can <br /> be found on Map 37, Springs and Stock Ponds Location <br /> map, which can be found in Volume 5 of the permit <br /> application. <br /> C . Surface Water <br /> The North Fork of the Gunnison River is the major <br /> drainage for the general area. Smaller streams in or <br /> adjacent to the life-of-mine areas are all tributary to <br /> the North Fork. Figure 1 contains the drainage map of <br /> the study area with the locations of streams and <br /> reservoirs which are described in the following <br /> discussion. <br /> The North Fork has an average annual streamflow at <br /> Somerset of approximately 313,500 acre-feet per year <br /> (1962-1979) . The flow is regulated by the Paonia <br /> Reservoir on Muddy Creek five miles upstream of the <br /> town of Somerset. The reservoir became operational in <br /> 1962. Water yields during that period have ranged from <br /> a high of 601 ,800 acre feet per year in water year <br /> 1984, to a low of 82,270 acre feet in water year 1977. <br /> Flow records for the North Fork of the Gunnison River <br /> near Somerset are given in Table 1 . Water quality <br /> parameters for the North Fork are given in Table 2. As <br /> indicated, water in the North Fork is a calcium <br /> bicarbonate type. There are also moderate levels of <br /> sulfate and salinity averages less than 100 mg1l . <br /> -33- <br />