2021-08-06_PERMIT FILE - C1982056A (2)

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(a) Each applicant shall contain a detailed description with appropriate maps, which are prepared to the standards of 2.10, and cross-section drawings of the measures to be taken during and after the proposed surface or underground mining activities, in accordance with Rule 4 to ensure the protection of: (i) The quality of surface and ground water, within both the proposed perinit area and adjacent areas, from adverse effects of the proposed surface or underground mining activities; PROTECTION OF WATER QUALITY TC will utilize a combination of control methods, reflecting best available control technology to minimize changes to water quality and the prevailing hydrologic balance in both the permit area and adjacent areas. These water quality control measures will be implemented in order to minimize long-term adverse changes in the hydrologic balance, which could result from mining. Discussions relative to the quality and quantity of surface and ground water of the Fish Creek Tipple operation are found within Volume VII of the Fish Creek Tipple/Loadout Appendix,pages 2.05-77 through 2.05-90. Surface Water Quality Protection The primary methods for erosion, sediment, and drainage control are based on minimizing the impacts of current and planned future surface disturbance by, munimizing disturbance, controlling runoff and capturing as close to the disturbed areas as possible, and stabilizing and revegetating disturbed areas as soon as practicable,. Where appropriate, runon from undisturbed areas will be intercepted and diverted around disturbed areas to minimize erosion and sediment transport and minimize treatment requirements. Diversion and collection structures are shown on Map 24, Surface Facilities. They serve to divert water from undisturbed areas away from disturbed areas and from disturbed areas to sediment control facilities. Not only does this diversion system reduce the amount of water flowing across disturbed areas and thus reduce water velocity and sediment yield, it also reduces the size and number of sedimentation ponds required. Temporary diversion structures are designed and will be constructed and maintained to handle the amount of runoff from the 10-year, 24- hour precipitation event with the exception of Ditch D-3 which is designed, constructed and maintained to handle the amount of runoff from a 100-year, 24-hour event. All diversions are constructed using proper roughness characteristics, maintenance of appropriate gradients, revegetation, channel lining or detention basins, or a combination of one or more of these measures. Therefore, they are adequate for their intended purpose, but also, to the extent possible, prevent additional contributions of suspended solids to streamflow and runoff outside the Permit Area. Discharge of effluent from the Foidel Creek Mine is controlled through a network of underground sumps and discharged through boreholes in the rock slope at Entry No. 3 (Site 109), at the west end of the 6-Left entry (Fish Creek Borehole), at the west end of the 10-Right entry, and at the 5-Main North Entry. Site 109 historically discharged to Ditch D-2 at the surface which delivers the effluent to Pond D. As an alternative to maintain operational flexibility, the water from the 109 discharge may be piped over to Site 114. Water collected in the mine portal wedge area is routed to a sump in the northwest corner of the wedge and pumped to Pond E, via Ditch E-1. Similarly, this water may be piped over to Site 114. Water discharged from the Fish Creek borehole is treated using flocculant or an electo-coagulation system and a series of settling cells and then discharged to Fish Creek at Site 115. The configuration of this system is shown in Map 32 and system operation is discussed in Section 2.05.3(4). Water Discharged from 10-Right or the 5-Main North locations can be treated by the proposed 6MN Passive Treatment System prior to discharge to the mine water system. The locations of sedimentation ponds are shown on Map 24, Surface Facilities. Generally, ponds and spillways were sized and located according to such hydrologic factors as required sediment storage volume, rate of flow and volume of flow for the appropriate storm event. All ponds have been designed to treat effluent as documented in Exhibit 8, Sediment Control Plan and Exhibit 30, CDPS/NPDES Permits (CO-0027154, CO-0036684, CO- 0042161, COG-850051, COG-850054, COR-03F087, and COR-040126). TR16-84 2.05-128 06/20/16