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-25- <br />Fracturing only minimally improves the water-bearing qualities of the <br />discontinuous sandstones and shales overlying the mines. Same fractures and <br />faults transect the Mesa Verde Formation and extend vertically to the <br />surface. These faults and fractures produce narrow bands of secondary <br />porosity within the rock strata. Due to the low permeability of the rock <br />strata within the Mesa Yerde Formation, these faults and fractures provide the <br />primary path through which water flows both vertically between rock strata and <br />horizontally within rock strata. <br />When faults and fractures are encountered within the mines in the North Fork <br />region, they generally produce mine inflows. The flow characteristics of each <br />mine inflow associated with faults and fractures depend upon the lateral <br />extent and the proximity of the fault or fracture to a stream valley. Since <br />most stream channels in the North Fo-ic drainage basin are developed in zones <br />of weak fractured rock associated with fracturing and faulting (Dunrud, 1976), <br />mine inflows from fractures and faults below these streams mimic the temporal <br />flow characteristics of the overlying streams. In the HaMc's Nest Mine, an <br />inflow was encountered under the ephemeral drainage of Hawk's Nest Creek. The <br />rates of inflow beneath this drainage fluctuate seasonally with a slight lag <br />time in response to the flaws in the overlying stream. In the Somerset Mine <br />and Blue Ribbon, inflows beneath and adjacent to Hubbard Creek are continuous <br />and reflect the perennial nature of this stream. All inflows from these <br />sources are characterized by an initial surge of water which then either <br />decreases significantly, or ceases completely with time. <br />To date, the Orchard Valley Mine has experienced maximum inflows of around <br />1500 gpd. This inflow came from both the floor and roof and were generally <br />roof drips or wet areas on the floor. Mining has progressed below East <br />Roatcap Creek and mine inflows have increased, but still remain insignificant <br />to the local hydrologic regime. <br />Inflows from faults and fractures located outside stream valleys (such as in <br />the Orchard Valley Mine) generally dry up with time or flow intermittently at <br />discrete points along the fault or fracture. Those which continue to flow <br />have flow rates which diminish to a trickle. Such inflows mdy represent the <br />dewatering of lenticular sandstone units with limited recharge areas, or may <br />represent flows through fracture zones extending to the surface which have <br />narrow recharge zones on steep slopes. <br />Preliminary aquifer tests were performed by West Elk Coal Company (WECC) on <br />the Barren member of the Mesa Verde Formation in September, 1975. The <br />preliminary transmissivity obtained for this member was calculated to be 2.46 <br />g/d/f t. Also, WECC performed a preliminary aquifer test on a fractured area <br />in the "F" seam which yielded a transmissivity of 16.68 g/d/ft. Another "F" <br />seam well completed in an unfractured area in the coal seam was dry. These <br />aquifer tests indicate that the "F" seam and the lenticular sandstones of the <br />Barren member are poor aquifers at best, as ground water flow is mainly <br />concentrated in fractured rock. <br />Occurrences of ground water have been noted in the Mesa Yerde Formation from <br />info nation obtained from drilling, experience in the mines, and frrom the <br />presjence of springs and seeps in the region. This information also indicates <br />that' the only potential regional bedrock aquifer in the generel area is the <br />