2012-11-15_REVISION - C1982057 (3)

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Seneca Coal Company Seneca II —W Mine SL-4 - Phase I Bond Release Request SL-4 -6 November 2012 Postmine Channel PM -4D This channel was excluded from the previous SL -3 bond release due to excessive erosion from the spring runoff event. The channel has been repaired with the placement of riprap and TRM to control the velocity of future runoff. The location of this channel is shown on attached Exhibit B, Postmining Topography and Drainage Map. Sediment Ponds — 005, 006, 009, 015, 016, and 017 The Seneca II -W permit area contains six (6) sediment ponds that are proposed to remain as permanent structures following reclamation. The pond locations, which include Ponds 005, 006, 009, 015, 016, and 017, are shown on Exhibit B, Post Mining Topography and Drainage. These impoundments will support the post mining land use of rangeland, livestock grazing, and wildlife habitat. Under applicable provisions of Rule 4.05.9(13), the permanent ponds must meet the following criteria: (a) The quality of the impounded water shall be suitable on a permanent basis for its intended use, shall meet applicable state and federal water quality standards and discharge of water from the impoundment shall meet applicable State and Federal effluent limitations and shall not degrade the quality of receiving water below applicable stream standards; (b) The level of water shall be sufficiently stable, and the configuration of the pond shall be adequate, to support the intended use; (c) Adequate safety and access to impounded water shall be provided for proposed water users; (d) Water impoundments shall not result in the diminution of the quality or quantity of water available to water right holders for agricultural, industrial, recreational, or domestic uses except in accordance with applicable state law; (e) The size of the impoundment shall be adequate for its intended purposes; (f) The impoundment shall be suitable for the approved post - mining land use. The landowner request letter is contained in Appendix 20 -2.1 of the permit document. In addition, the Office of State Engineer must also approve retention of each pond. Landowner requests, permanent pond demonstrations, documentation of DRMS and State Engineer approval for each pond will be submitted prior to Phase I bond release approval. Stock Ponds There are nine (9) stock ponds (T -2, 3, 5, 18, 20, 22, 24, 26, and 27) that will remain permanent following reclamation. The stock ponds were constructed in reclaimed area and are not primary sediment control structures. They have a storage capacity of less than two -acre feet and an embankment no greater than five feet high measured from the invert of the spillway to the upstream toe of the embankment. Given that the stock ponds are relatively small in size and there are no residential or commercial structures or mining operations immediately below the structures, they do not create a threat to public health and safety or threaten significant environmental harm. These permanent stock ponds will enhance the approved post mine use. The pond locations are shown on Exhibit B, Post Mining Topography and Drainage. Landowner requests, permanent pond demonstrations, documentation of DRMS and State Engineer approval will be submitted prior to Phase I bond release.