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running in an arcuate line northward through the west central part of the basin shows <br />displacement of 0 to 80 feet. Smaller lateral faults were encountered in the 9 Right and 10 Right <br />gateroads while driving development out into the Eastern Mining District. <br />The near surface bedrock units are composed of sedimentary rocks of marine and non -marine <br />origin. These sedimentary rocks were formed through the transgression and regression of an <br />epicontinental sea and are comprised of sequences of sandstones, siltstones, shales and coal. <br />Four geologic formations exist in the vicinity of the Foidel Creek Mining Districts. They are, in <br />ascending order, the Mancos Shale, the Iles and Williams Fork Formation of the Mesaverde <br />Group, and the Lewis Shale. These strata were all deposited during the late Cretaceous Period. <br />Generally, the strata dip to the center of the basin. <br />Coal Seam Stratigraphy <br />Three economically important coal seams, the Lennox, Wadge, and Wolf Creek coals, are <br />located within the locally important Middle Coal Group of the Williams Fork Formation. TC is <br />currently mining coal in the Wadge Coal Seam. The Wadge Coal seam was strip mined in <br />CYCC's adjacent Energy Mine No. 1, Energy Mine No. 2, and Eckman Park Mines (No. C-81- <br />071) and Energy Mine No. 3 (C-84-062). The Wadge coal seam, in the area of the Foidel Creek <br />Mine, is separated from the underlying Trout Creek sandstone by about 250 feet of interbedded <br />sandstones, siltstones, shales and coals. The Wadge coal seam is separated from the overlying <br />Twentymile sandstone by 700 feet of massive shale and interbedded sandstones, siltstones, <br />shales and coals. Overburden depths in the current permit area range from 0 to 1,700 feet. <br />TC also mines within the Wolf Creek Seam. TC was given approval to conduct development <br />mining within this seam with the approval of TR83 in December of 2014. PR -11 proposes to <br />update the mining plan to conduct development mining and longwall mining of this seam in the <br />4RT to 9RT longwall panels as depicted on Map WC23 dated July 1, 2015, proposed to be <br />approved with PR -11. The Wolf Creek Coal Seam splits into four distinct benches, the <br />combined total seam thickness ranges from 7.5 to 14 feet. Between the Wadge Coal Seam and <br />the Wolf Creek Seams, there is interbedded sandstone and shales. Interbedded sandstones and <br />shales and the massive Trout Creek Sandstone are below the Wolf Creek Seam. <br />Surface Water Hydrology <br />The mine is located in the upper reaches of the Yampa River Basin. The permit area and <br />adjacent areas are drained by Foidel Creek, an intermittent stream, and Fish Creek and Middle <br />Creek, both perennial streams. Fish Creek drains east into Trout Creek whereas Foidel Creek <br />drains northeast to Middle Creek before Middle Creek joins Trout Creek. The quality of water in <br />the Fish Creek and Foidel Creek drainages has been affected previously by surface mining <br />upstream and downstream of the underground mine's existing surface facilities. Alluvial valley <br />floors are identified downstream of the mining area at the confluence of Foidel and Middle <br />Creek, and on Trout Creek from its confluence with Middle Creek downstream to the Yampa <br />River. Permit Revision No. 3 declassified portions of Foidel and Middle creeks previously <br />classified as AVF's. Detailed discussion concerning alluvial valley floors can be found in <br />Section B, part XVIII of this document as well as Exhibit 7j of the permit. <br />Foidel Creek Mine 11 February 25, 2016 <br />