2013-10-17_PERMIT FILE - C1982056A (4)

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The Wadge Overburden yielded water to the mine workings in the 6 Right development entries. The entries are located in an area of high strain due to an anticline. The water yielding zone was encountered during late 1997. In addition to the high stress zone the area is located downdip of the low wall from the adjacent CYCC surface mine. It appears that this combination of factors provides a conduit for water to follow into the underground mine from the adjacent surface mine. High flows in this area of the mine were measured at approximately 200 gpm, and now (11/99) have dropped to approximately 50 gpm. TCC will continue to monitor this inflow, as long as mine conditions allow and report it in the AHR. Foidel and Middle Creeks Twentymile Coal Company is not anticipating any material damage or diminution of use to either Foidel or Middle Creeks. Exhibit 7E contains the subsidence predictions for both of the creeks. Exhibit 7I further expands the description of worst -case subsidence and substantiates Twentymile's position that no material damage will occur nor will repairs be required. This position has been substantiated by the experience gained with subsiding the segment of Foidel Creek overlying panel 9 Right. The creek subsided and a small pool was formed in the subsidence trough. Flows were temporarily disrupted, but have been returned to normal conditions. The same response of the creek is anticipated as mining progresses in the Eastern Mining District. Face Extension and Gateroad Development (TR 99 -33) The subsidence prediction for the face extension area is presented in Exhibit 7E -5. TCC is not anticipating any further impacts from the mining activity. The impacts presented in permit revision 97 -04 apply to the mine area. Northern Mining District (Panels 12 Right through 16 Right)(PR 99 -05) The proposed mining in the NMD should not result in the material damage or diminution of reasonably foreseeable use of structures or resources in the five -year mine plan. The structures, which will be subsided, within the five - year mine plan area include County Road 33, powerlines (Public Service, Western Area Power Association, Yampa Valley Electric Association, and jointly -owned line), telephone lines (U.S. West), Twentymile Sandstone, Union Pacific Railroad Track (formerly Southern Pacific), Foidel and Middle Creeks. It should be noted that monitoring well 006BRDH7 will be subsided and potentially destroyed. If the well is destroyed, it will be grouted and permanently abandoned. County Road 33 In reference to County Road 33, Twentymile has gained recent experience with undermining and subsiding this road. The experience indicates that either tensional or compressional fractures may be manifested in the road PR 03 -06 2.05 -184.2 05/07/03