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1998 have shown that the primary source of inflows are from fracmres <br />in areas of low overburden. <br />As previously described in this document, MCC encountered a large <br />inflow of water while mining through afault/fracture system in the <br />B East Mains and a separate fault in panel 14. As of the date of this <br />findings document, MCC continues [o experience mine inflow on the <br />east side of the mine. <br />Since the geologic strata dips to the northeast, one would expect the <br />groundwater to flow in the same direction. This is generally true, but <br />because the groundwater occurs in discontinuous lenses, some wells <br />are dry, indicating no groundwater flow and other wells that are closely <br />spaced but completed at different portions of the Barren Member have <br />water levels that vary greatly. Generally, springs in the permit area <br />seem to act independently of the bedrock water zones and appear to be <br />originating in the alluvial and colluvial material. Flow from these <br />springs tend to be ephemeral and only discharge during spring snow <br />melt. These springs recharge and discharge in relatively small areas. <br />Inflows from faults and fractures located outside stream valleys <br />generally dry up with time or flow intermittently at discrete points <br />along the fault or fracture. Those which continue to flow have flow <br />rates which diminish to a trickle. Such inflows may represent the <br />dewatering of lenticular sandstone units with limited recharge areas, or <br />may represent flows through fracture zones extending to the surface <br />which have narrow recharge zones on steep slopes. <br />Discharge of groundwater occurs through 83 seeps and springs_located <br />in the life-of-mine area. The locations of these springs can be found on <br />Map 37 and, Springs and Stock Ponds. <br />c. Surface Water <br />The North Fork of the Gunnison River is the major drainage for the <br />mine area. Smaller streams in or adjacent to the life-of-mine areas are <br />all tributary to the North Fork. Figure 2 of this document contains the <br />drainage map of the study area with the locations of streams and <br />reservoirs which are described in the following discussion. <br />The North Fork has an average annual streamflow at Somerset of <br />approximately 313,500 acre-feet per year (1962-1979). The flow is <br />regulated by the Paonia Reservoir on Muddy Creek five miles upstream <br />of the town of Somerset. The reservoir became operational in 1962. <br />Water yields during that period have ranged from a high of 601,800 <br />acre feet per year in water year 1984, to a low of 82,270 acre feet in <br />31 <br />