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

Home Browse Search

Ground Water Ouantitv Protection No registered wells are completed in the Trout Creek Sandstone in the central part of the Twentymile Park Basin except those owned by TCC. There are also no registered wells completed in the Twentymile Sandstone in this part of the Basin. Groundwater rights in the permit area and vicinity are shown in Table 9. In the unlikely event that underground mining activities cause adverse quantitative injury to another water user, TCC or a subsidiary would utilize their ground water rights within the general area to mitigate any such injury. Know uses of ground water are identified and discussed under Rule 2.04,7(1)(a)(iii) starting on page 2.04-33. div) The quality of surface and ground water affected by any underground mines by locating mine openings in accordance with 4.05.10. The mine portals are designed such that no gravity discharge of water from the mine occurs. Water from the disturbed portal wedge area or rock slopes is routed to Pond E, or alternatively, it may be piped to Site 114. No water will be discharged by gravity from the Fish Creek Borehole/Shaft. The description shall include: (i) A plan for control, in accordance with Rule 4, of surface ground water drainage into, through and out of the proposed permit area and adiacent area: Drainage Control and Treatment Plan Previous operations plans for the Foidel Creek Mine created certain changes in the original sediment -control plan implemented under the previously approved Permit No. 79-177. The most significant changes were a result of the variance from contemporaneous reclamation requirements to allow a portion of the Area 1 surface mine pit to remain open and to serve as a disposal site for waste rock material from the underground mine. Exhibit 31, Spoil Analysis, contains recommendations for drainage control near the portal area. As stated, the crest of the highwall is a topographic drainage divide, and surface drainage north of the crest drains away from the highwall (into Ponds, D, E, F, and G, as shown on Map 24, Surface Facilities). This plan provides for drainage of the area south of the surface facilities utilizing two diversion ditches. Ditch D-4 is located at the toe of the spoils slope, and Ditch D-3 at the crest of the spoil slope, as shown on Map 24, Surface Facilities, and specified in Exhibit 8, Sediment Control Plan. Ditch D-3 is designed for the 100 -year, 24-hour precipitation event to provide a measure of safety and stability to the spoil slopes. All other drainage control measures are designed for the 10 -year, 24-hour event. The plan calls for the Area 1 Pit water to be allowed to overflow into Pond D, with discharge to Foidel Creek, as shown on Map 24, Surface Facilities. Thus, all water from disturbed lands pass through sedimentation ponds before being released to Foidel Creek, except for Small Area Exemptions. TCC has assumed the operational and reclamation liability for ponds/treatment facility B, C, D, E, F, G, and T since the completion of mining at Colorado Yampa Coal Company. Pond B, which is a treatment facility, receives wash - down water and surface runoff from the tipple and Belt -Out -Back stockpile. Pond C controls runoff from the old loadout stockpile and its associated pad. Pond D receives surface runoff, spoils discharge from the Area 1 Pit, and mine water. Pond E receives runoff from the surface facilities, including surface water from the Wadge Sump. Pond F receives runoff from the surface facilities, upland reclaimed area, and spoil water. Pond G receives runoff from the surface facilities and upland reclaimed areas. Design details for these ponds are presented in Exhibit 8. TCC also constructed the 6MN Mine Water Storage Reservoir to provide additional water storage capacity for the operational mine water system. With a compacted clay liner with a permeability of approximately 2.0 x 10-' cm/in, groundwater infiltration will be minimal, with minimal potential for impacts to groundwater or associated alluvial surface water. Additionally, TCC utilizes diversion ditches to route the 100 -year flow event around the refuse pile. The design of the refuse pile diversion ditches is presented in Exhibit 26A, Appendix D. These diversions take upland flow and divert it around the perimeter of the refuse pile in accordance with the DMG regulations. TR07-61 2.05-130 09/26/07