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-_. <br />approximately 1.5 ft in width (25070 µe). The predicted roughly <br />perpendicular tensile fracture crossings of Bear Creek can channel <br />surface water downslope toward the creek, but not away. Water flowing <br />in Bear Creek should rapidly fill open subsidence fractures in its <br />channel. In alluvium, the magnitude of the maximum predicted <br />compressive strains at the ground surface range from nearly <br />undetectable (3330 µE) to compression ridges approaching 1 ft in height <br />(19670 µE). " <br />Water flowing in Bear creek will cause tensile fractures to heal within a short period of time. <br />Compression ridge materials will be re-distributed. Siltation, deposition and consolidation of <br />these streambed materials and alluvial materials will result in the collapse and filling of these <br />surface features. Subsidence, therefore, should not result in any significant alteration of surface <br />flow patterns or drainage into underground mine workings. <br />On page 4?, the author aiso states: - <br />"Chimney subsidence that may eventually develop in the roof of planned <br />entries, longwall panels and gateroads should not breach the ground <br />surface. The theoretical maximum predicted conical collapse is ten <br />times the mining height... Obviously, the rectangular collapse above a <br />longwall panel will not breach the ground surface through 280 ft of <br />overburden to Bear Creek. The high percentage of sandstone, <br />approximately 60%, in the interburden and the high percent free swell of <br />sandstone when broken, further reduces the potential for adverse <br />chimney subsidence effects. " <br />We also direct the Division to an additional document to be moved to the reorganized Exhibit <br />2.05-E8 (formerly located in Exhibit 2.05-E2) titled Predicted D-Seam Longwall Impact on Bear <br />Creek (Abel, September 19, 1998). The author provides an extensive description of the <br />extremely small potential for water loss from Bear Creek as the result of the planned longwall <br />mining of the "D" seam. <br />Please contact me at 970-929-5806 if you have questions or need additional information. <br />Sincerely, <br />~~~~~ <br />~mes A. Kiger <br />l Envtronmental Specialist <br />Enclosures <br />Xc: Kathy Welt <br />Sle <br />~~ ~o <br />