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West Elk Mine <br />• Canyon Sealed Sumps is not expected to increase groundwater inflows within the abandoned <br />downgradient mine workings primarily due to the low permeability of the coal and the lack of <br />hydraulic connection between the mines via the fault systems. <br />• In January 1997, MCC appropriated the nontributary groundwater fault inflows and <br />sump storage areas. MCC adjudicated these rights by decree (Case Nos. 97CW242, <br />97CW243 and 97CW244) through the Division 4 Court system in 1999. <br />• MCC obtained approval for the Lone Pine Gulch pipeline dischazge point (Outfall #013) to <br />dischazge mine water from the NW Panels sealed sump. The quality of the water within the <br />sump was evaluated and found to be of sufficient quality so as not to require ,additional <br />treatment prior to discharge to Lone Pine Gulch. <br />• MCC constructed a 2,000 gpm pumping facility in Sylvester Gulch in August 2000 for <br />mine water outflow waters. The facility was designed to allow for rapid expansion, <br />including a treatment system if necessary. <br />In short, the BEM Fault inflow in March 1996 and the 14HG Fault inflow in January 1997, <br />prompted MCC to take many aggressive steps to improve mine inflow management. <br />At the present time, seven southwest to northeast trending fault systems have been <br />identified in the West Elk Mine permit area More specifically, the faults generally trend <br />• N60E to N70E with dip angles of 70° to 85°. This orientafion is parallel to subparallel to the <br />dominant joint set at N58E to N64E. The tectonic faults are believed to have formed by <br />activating the existing joint system to form the fault zones. Four of these fault systems have <br />been encountered by previous mining. These include the unnamed fault at the bottom of <br />the entry slopes in the B Seam, the BEM Fault, the 14HG Fault and the "Oliver" Fault that <br />was encountered in the Oliver Mine near Sylvester Gulch. Three additional parallel fault <br />systems (named the West Flat-Iron, Deep Creek and Gunnison) have been identified by <br />drill holes, seismic or analytical techniques. Each is located approximately 2,000 feet apart <br />and with dip angles greater than 70° to the northwest. <br />Coal exploration drilling has not encountered fault zones or associated fault waters. The <br />near vertical nature of the faults, the diminishing displacement of the faults as they <br />approach the surface, the vertical aspect of coal exploration holes, and the inability to <br />precisely pinpoint undrained faults makes intercepfion with drilling difficult and unlikely. <br />A single surface methane drainage well was drilled across a known fault zone using <br />directional drilling methods. The hole successfully vented methane but did not encounter <br />water. <br />None of the monitored springs appear to be located on any of the known fault zones. The <br />springs nearest the faults do not appear to have been affected by the in-mine dewatering of <br />the faults. The changes in measured flows at these spring locations appear to be the result <br />of varying climatic conditions. <br />I• <br />2.05-254 Revised June 2005 PR/0; Rev. March 2006; Rev. May 2006 PRIO <br />