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Some fractures and faults transect the Mesaverde Formation and <br /> extend vertically to the surface. These faults and fractures produce <br /> narrow bands of secondary permeability within the rock strata. Due <br /> to the low permeability of the rock strata within the Mesaverde <br /> Formation, these faults and fractures provide the primary path through <br /> which water flows both vertically between rock strata and horizontally <br /> within rock strata. <br /> When faults and fractures are encountered within the mines in the <br /> North Fork region, they generally produce mine inflows. The flow <br /> characteristics of each mine inflow associated with faults and fractures <br /> depend upon the lateral extent and the proximity of the fault or <br /> fracture to a stream valley. All inflows from these sources are <br /> characterized by an initial surge of water which then either decreases <br /> or ceases completely with time. <br /> Locally, water flow through fractures probably occurs more rapidly, <br /> as suggested by the seasonal fluctuation in discharge rates of some <br /> springs in the mine plan area. Mine inflow studies conducted as <br /> recently as 1985 have shown that the primary source of inflows are <br /> from fractures in areas of low overburden. <br /> Since the geologic strata dips to the northeast, one would expect the <br /> ground water to flow in the same direction. The monitoring wells <br /> generally support this, but there are exceptions. Some wells are dry, <br /> indicating no ground water 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. This may indicate the discontinuity of <br /> the water bearing strata. Generally, springs in the permit area seem <br /> to act independently of the bedrock water leasing zones and appear to <br /> be surface features related to weathered and fractured bedrock. Flow <br /> from these springs tend to be highly ephemeral and only discharge <br /> during spring snow melt. These springs recharge and discharge in <br /> 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, <br /> or may represent flows through fracture zones extending to the surface <br /> which have narrow recharge zones on steep slopes. <br /> Discharge of ground water occurs through numerous seeps and <br /> springs. Over 100 springs are located in the life-of-mine area. The <br /> locations of these springs can be found on Map 37 and 37A, Springs <br /> and Stock Ponds Location and Springs and Ponds, Jumbo Mountain, <br /> respectively. <br /> 25 <br />