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West Elk Mine • lenticular and laminaz sandstones of the Mesaverde Formation; and (d) The Rollins Sandstone." (p. 4). 2. "Observations made underground by the staff of the Division at mines in the region showed that the coal seams aze poor aquifers with very low transmissivities." (p. 4). 3. "Fracturing improves the water-bearing qualities of the discontinuous sandstones and shales overlying the mines. Some fractures and faults transect the Mesaverde Formation and extend vertically to the surface. These faults and fractures produce narrow bands of secondary porosity within the rock strata. Due to the low permeability of the rock strata within the Mesaverde Formation, these faults and fractures provide the primary path through which water flows both vertically between rock strata and horizontally within rock strata." (p. 4). This statement is generally true, except that in the eastern portion of West Elk Mine (B East Mains and 14SE Headgate) a fracture/fault system was of sufficient size and storage capacity to generate initial inflow rates of approximately 2,500 and 8,000 gpm, respectively. As is typical of fracture-controlled reservoirs in the oil industry, and as MCC has experienced with other inflows in the mine, these inflows reduced to a fraction of the initial inflow rates within a few months (to 80 gpm in the case of the BEM Fault, which is about 3 percent of the initial flow rate). The 14HG Fault inflow also reduced to less than 3 percent of the initial inflow rate of 8,000 gpm. It is important to contrast the amount and nature of surface cracking associated with longwall • mining versus room-and-pillaz mining. Based upon cazeful field inspections of the ground surface above West Elk Mine's 1NW through 7NW longwall panels, Mr. Dunrud has determined that longwall mining in this setting produces very few surface cracks, and that when cracks do appeaz, they aze located only in areas of maximum stress and aze likely to "seal" themselves. Detailed discussion regazding the frequency ("risk") of surface cracks based upon inspection of these panels is provided in Section 2.05.6, Surface Water Quantity Effects, Streams. This section concludes that the probability of any given channel in the South of Divide permit revision azeas encountering a crack is 0.2 percent, (see calculations in discussion entitled Analysis of Impacts to Streams) and that the total annual loss of surface flow to cracks will be of no practical significance. 4. "Inflows from faults and fractures located outside stream valleys, such as in the Bowie No. 1 Mine, generally dry up with time or flow intemuttenfly at discrete points along the fault or fracture, with the exception of the most recently encountered West Elk Mine inflows. Those which continue to flow, have flow rates which diminish to a trickle. Such inflows may represent the dewatering of lenticulaz sandstone units with limited recharge azeas or may represent flows through fracture zones extending to the surface which have narrow recharge zones on steep slopes." (p. 5). In every case, inflows have rapidly diminished to a fraction of the initial inflows or in many cases have ceased entirely. In the cases of the BEM Fault and the 14HG Fault, inflows encountered in Mazch 1996 and January 1997, respectively, the inflows decreased to about 3 percent of the maximum observed inflow rates after a few months. 2.05-152 Revised November 2004 PRIO