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Peab i dU 1111 ENERGY Twentymile Coal, LLC R�G N�V 251��4 or, o�R�aie�Y Jason Musick pv� Ma9& Colorado Division of Reclamation, Mining, and Safety 1313 Sherman Street, Room 215 Denver, Colorado 80203 (303) 866 -3567 X8134 29515 Routt County Road 27 Oak Creek, CO 80467 970.879.3800 November 17, 2014 RE: Twentymile Coal, LLC - Foidel Creek Mine (Permit No. C -82 -056), Minor Revision (MR14 -284) Loadout Drainage Modifications and SAE Mr. Musick: Twentymile Coal, LLC (TC) requests CDRMS approval of a Minor Revision to our existing approved Permit for modification of the Loadout Area drainage configuration to address existing drainage concerns and to provide documentation of the Small Area Exemption (SAE) for this area. Given the configuration and type and level of activities in this area, the present drainage and sediment controls are marginally adequate and need to be modified and upgraded in order to be effective. The drainage and sediment controls for this area were approved under an SAE, as referenced in the Permit text, however, adequate documentation for the approved SAE is lacking, so this MR submittal also provides expanded SAE documentation. The existing Loadout Area SAE includes the loadout building, the loadout pad area, and a segment of the rail spur extending to the east of the loadout. Drainage from this area is presently controlled by gravel surfacing on the pad area, a collection ditch with check dams and booms paralleling the rail spur, and a rock -lined sump between the pad area and Foidel Creek. Under snowmelt or heavy runoff conditions, with the current configuration of the pad area, the potential exists for drainage from the pad area to bypass the sump and go directly to Foidel Creek, and for the capacity of the existing controls in the rail spur collection ditch to be exceeded. TC proposes to reduce the pad area on the north side of the rail spur by removing the accumulation of coally material, and regrading and reseeding part of this area, leaving only an access road along the north side of the spur. The drainage configuration of the remaining pad area would also be modified by filling a low area and placing a berm to direct all drainage to the collection sump. The sump capacity and function would be expanded by constructing a second sump in series, removing accumulated sediment from the existing sump, and rebuilding the rock perimeter filter. The control capacity of the rail spur collection ditch would be increased by excavating several sediment traps in the ditch and adding additional rock check dams. The proposed drainage modifications fall within areas previously disturbed by mining and related activities, so no cultural resource survey or wildlife consultation were necessary. Long -term drainage and sediment control will be addressed under the Small Area Exemption (SAE) , using site drainage control measures, as documented by the included SAE analysis. Detailed drawings and a description of the proposed drainage modifications are provided as both revised PAP text and supporting materials, as identified by the attached Summary of Revisions /Additions.