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Subsidence impacts on Foidel Creek, Middle Creek, and Fish Creek <br />Subsidence of portions of Foidel Creek, Middle Creek, and Fish Creek will cause gradient changes in these <br />streams. These gradient changes will result in ponding and channel incision controlled by the streams' <br />relationship to orientation of the longwall panels and gateroads. Subsidence cracks in the near surface also <br />have the potential to disrupt the streamflow. Based on the presence of fine-grained alluvial material, any <br />disruption of stream flows would be temporary. Site-specific experience from Foidel Creek resulted in a <br />complete loss of streamflow for approximately 24 hours followed by a recovery over the subsequent two <br />months. <br />See Section B, part III B of this document for more information concerning the surface and ground water <br />monitoring plan. <br />The Division has evaluated each of these impacts and finds that the operations proposed under the <br />application have been designed to prevent damage to the hydrologic balance outside the proposed permit <br />area (2.07.6(2)(c)). <br />5. The Division finds that the affected area is, subject to valid rights existing as of August 3, 1977, not within: <br />a) An area designated unsuitable for surface coal mining operations (2.07.6(2)(d)(i)); <br />b) An area under study for designation as unsuitable for surface coal mining operations (2.07.6(2)(d)(ii)); <br />c) The boundaries of the National Park System, the National Wildlife Refuge System, the National System <br />of Trails, the National Wilderness Preservation System, the Wild and Scenic Rivers System including <br />rivers under study for designation, and National Recreation Areas (2.07.6(2)(d)(iii)(A)); <br />d) Three hundred feet of any public building, school, church, community or institutional building, or <br />public park (2.07.6(2)(d)(iii)(B)); <br />e) One hundred feet of a cemetery (2.07.6(2)(d)(iii)(C)); <br />f) The boundaries of any National Forest unless the required fmding of compatibility has been made by <br />the Secretary of the U.S. Department of Agriculture (2.07.6(2)(d)(iii)(D)); <br />g) One hundred feet of the outside right-of-way line of any public road except where mine access or haul <br />roads join such line, and excepting any roads for which the necessary approvals have been received, <br />notices published, public hearing opportunities provided, and written findings made. <br />PR-02 approved undermining a portion of Routt County Road No. 27 in Section 33 of T5N R86W and <br />Section 25 of T5N R87W. Routt County approved this undermining and subsidence of the road and the <br />Division stipulated that the written approval from Routt County be submitted prior to any longwall <br />mining below the surface of the road. The Division published notice of a public hearing in the <br />Steamboat Pilot on July 16, 1992. No comments concerning the mining within 100 feet of the right-of- <br />way were received from the public. Warning signs were posted along the road in the zone of <br />subsidence. Subsidence and rockfall due to mining in Panel 6 in the SW Mining District required that <br />the operator re-design the mitigative measures proposed originally under PR-02 to protect the use of <br />County Road No. 27 in Sections 33, T5N R86W and Section 25 of TSN, R87W. Technical revision 19 <br />(TR-19) approved construction of a trench/berm system approximately 4200 feet in length adjacent to <br />County Road No. 27 to stop any rockfall prior to reaching the county road. Exhibit 7a, Stability <br />Investigation of the Twentymile Sandstone Cliff, and Exhibit 7f, Rockfall Hazard Assessment and <br />15