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Some general conclusions can be drawn from the initial work described in Section 3, including: <br />1. With the exception of panel 4 -East, the majority of the movement associated with each longwall will 0 <br />occur over a one month period starting when the face is about 500 -feet from the rail line and ending <br />when the face is about 1,000 -feet past the rail line. This distance is measured parallel to face retreat. <br />2. During pre -ballasting, track differential gradients will generally be maintained below 0.4% between <br />adjacent Stations. Final differential gradients are predicted to be at or below 0.3% following subsidence <br />from each of the planned longwall panels. <br />3. Both of the two remedial methods outlined in this report have been successfully implemented during <br />undermining of the Energy Spur. There is every reason to conclude that they will continue to be <br />successfully applied to remediating subsidence associated with extraction of the panels in the Wolf <br />Creek Seam. <br />8.2. County Road 33 <br />Section 4 predicts that County Road 33 will be subject to just under 80 -inches of subsidence as it crosses over the <br />shallower panels in the Wolf Creek seam. Gradient changes of just under 1% and surface strains of 0.005 are <br />expected to result in surface cracking of the chip sealed surface. Prior mitigation of similar impacts to County <br />Road 33 has involved sealing of these surface cracks. <br />8.3. Fish Creek, Foidel Creek, and Middle Creek. <br />The evaluation presented in Section 5 predicts that Fish Creek will overflow its high bank(s) with the following 10 <br />impacts to Fish Creek and its floodplain: <br />1. A maximum increase in Fish Creek bottom gradient of 0.024 (2.4°0). <br />2. An increase in the surface area of Fish Creek following coal extraction in Panels 9 -East, 8- East, 7 -East, <br />and 6 -East of under 50 acres. Impacts to Foidel Creek are expected to be minimal with a predicted <br />increase in the surface area of Foidel Creek following coal extraction in Panels 1 -East through 4 -East of <br />under 5 acres. <br />It is our understanding that the magnitude of predicted surface water area changes in the Northern Mining District <br />contained in our 1999 and 2002 reports and over the Western Mining district in 2009 were never realized <br />illustrating the conservative nature of these predictions. This is likely due to the dynamic process where <br />differential subsidence displacements are readily accommodated by the natural processes of erosion and <br />deposition that occurs rapidly under the high flow conditions experienced during spring months. <br />8.4. Power Transmission Lines. <br />Several conclusions can be drawn from the preliminary work, described in Section 6, including: <br />1. Structures on the Foidel Creek -Steamboat line are predicted to subside by up to 6 -feet <br />2. Structures on the Archer -Hayden line are predicted to subside by just over 4.5 -feet. <br />3. Structures on the Craig -Hayden -Steamboat line are predicted to subside by just over 4 -feet <br />4. Maximum daily subsidence is predicted to be less than 6 -inches per day. <br />20 <br />