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TR-11 Adequacy Review Comments 1. Reclaimed Configuration Maps in the revision application depict drainages A, B, C, D, E, F, G and H, that need to be restored across the access road, with drainage basin flow calculations and reclaimed channel designs given in Table 3.9-3. There appear to be some discrepancies between the revised information and current permit documentation. Permit Appendix M contains haul road culvert designs, along with associated drainage basin characteristics. In several instances, peak flow calculations and watershed acreages specified in Table 3.9-3 differ from those given in Appendix M, and depicted on the Surface Hydrology Map (2.3-4). Also, the watershed boundaries presented in the revision application are labeled differently than in the permit appendix. In order to adequately review the channel designs, an accurate and complete map of the watershed boundaries corresponding to the drainage basins as designated in Table 3.9-3 will need to be provided. 2. Diversion H crosses over the main portion of the mine. It does not appear that the curve number (CN) used in the design for the watershed area reflects newly backfilled and topsoiled disturbance. The CN should be revised accordingly. 3. The revision application does not include permanent channel reconstruction designs for Munger Creek drainage (72" culvert), the 42" culvert drainage, or the 18" culvert drainage depicted on Figure 3.1-10. Please note that ephemeral streams draining a watershed of at least one square mile above the diversion need to be designed for a 100 year, 24-hour precipitation event. The reclaimed channel designs for the noted drainages will need to be submitted. 4. The application text or design drawings for the reclaimed channels should be amended to address how riprap will be keyed in place across the reclaimed road. Key cuts would appear to be necessary where the drainages intersect the reclaimed portion of the road and where they enter the natural drainage. 5. All existing road culverts should be depicted on the Existing Configuration plan view maps. The upland diversion ditch for the mine pad area and the water bar on the pre-law exploration road referenced in the text which diverts drainage away from the highwall should be depicted on Figure 3.1-4 (Existing Configuration), and the water bar, which should remain in place following reclamation to divert upland drainage away from the reclaimed slope, should be depicted on Figure 3.1-7 (Reclaimed Configuration). Existing road drainage ditches should be addressed in design drawings or text, and sizing calculations should be included for all existing culverts, road ditches, and diversions, including the water bar above the highwall. Culvert inlet and