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laterally continuous Rollins Sandstone. The laterally <br /> discontinuous lenticular sandstones within the Upper <br /> Mesaverde Formation support only localized ground water <br /> flows. <br /> Recharge to the Rollins Sandstone occurs along <br /> outcrops , along subcrops beneath stream alluvium and in <br /> the channels of the North Fork and its tributaries. <br /> However, due to the steepness of the topography in the <br /> outcrop areas (i .e. , sandstones are ledge formers) and <br /> the narrowness of the stream valleys , these local <br /> aquifers receive little recharge. Some recharge to the <br /> continuous units and much of the recharge to the more <br /> discontinuous, lenticular units will come directly from <br /> the percolation of snowmelt and precipitation downward <br /> through sandstone lens and along fractures . Of 112 <br /> exploration drill holes at the West Elk Mine that were <br /> drilled prior to the mine opening, only three of the <br /> holes produced water from the F seam at a production <br /> rate of 3 gpm or less . Three other holes in the Barren <br /> member had rates of about 0.75 gpm. <br /> Some fractures and faults transect the Mesaverde <br /> Formation and extend vertically to the surface . These <br /> faults and fractures produce narrow bands of secondary <br /> permeability within the rock strata. Due to the low <br /> permeability of the rock strata within the Mesaverde <br /> Formation, these faults and fractures provide the <br /> primary path through which water flows both vertically <br /> between rock strata and horizontally within rock strata. <br /> When faults and fractures are encountered within the <br /> mines in the North Fork region, they generally produce <br /> mine inflows . The flow characteristics of each mine <br /> inflow associated with faults and fractures depend upon <br /> the lateral extent and the proximity of the fault or <br /> fracture to a stream valley. All inflows from these <br /> sources are characterized by an initial surge of water <br /> which then either decreases or ceases completely with <br /> time. <br /> Locally, water flow through fractures probably occurs <br /> more rapidly, as suggested by the seasonal fluctuation <br /> in discharge rates of some springs in the mine plan <br /> area. Mine inflow studies conducted as recently as <br /> 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 <br /> would expect the ground water to flow in the same <br /> direction. The monitoring wells generally support <br /> this, but there are exceptions. Some wells are dry, <br /> indicating no ground water flow and other wells that <br /> are closely spaced but completed at different portions <br /> -32- <br />