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All reestablished drainages are delineated on Map 1 of the bond release application, titled; SL25 Phase <br /> I Bond Release Area Delineation. TMI has put insignificant efforts in constructing drainages, in the <br /> past effectively controlling erosion and downstream sediment deposition. Various sediment control <br /> materials and methods and sediment reducing measures have been implemented on reestablished <br /> drainages. Drainages at Trapper Mine are trapezoidal in shape with a bottom width of approximately <br /> 20 feet, grass lined with regularly spaced check dams. Rock check structures dissipate the energy of <br /> flowing water within channels. Debris and sediment deposition occurs upstream of structures allowing <br /> vegetation to establish behind structures, further stabilizing the channels. This configuration results in <br /> shallow flow depths for the design storm and low flow velocities. Rock Channel slopes are generally <br /> 10 percent. Detailed engineering criteria regarding drainage reconstruction practices can be found in <br /> TMI's permit Appendix Q Section XXXVII. <br /> Bond Release Blocks Delineation <br /> As discussed in permit section 4.4.1,reclaimed parcels are compared to three different range standards <br /> based on elevation: <br /> 1. Range site A standards apply to elevations greater than 7200 feet. <br /> 2. Range site B standards apply to elevations between 6700 and 7200 feet. <br /> 3. Range site C standards apply to elevations below 6700 feet. <br /> The approved postmining land use for the land applicable to SL25 is rangeland/wildlife habitat. The <br /> revegetation plan is designed to achieve the approved postmining land use. The SL25 bond release <br /> block comprises all three range site types. The SL25 bond release block will be seeded with either <br /> Rangeland A,B or C seed mixes as appropriate to parcel elevation in autumn of 2024. Trapper Mining <br /> Inc. provided, in the SL25 application, documentation of the seed mixtures planned for each parcel. <br /> Seed mixes are in accordance with the approved reclamation plan. <br /> W- , <br /> 4 }. <br /> d. S <br /> y <br /> 5 <br /> Photo 4: Typical rangeland vegetation surrounding the I Pit. <br /> Permit Number C 19810 10 Prepared by: R.Reilley <br /> SL25 Page 8 of 21 <br />