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compiled and submitted b)• the following March 1 to the DMG in the form of the Yoast Annual • Hydrology Report (AXR). Surface Water Protection Tab 13 (Facilities) contains descriptions, designs, and plans for sediment ponds, roads, diversions, and culverts that have been or will be constructed and utilized at the Yoast Mine. All facilities [hat ere discussed in Tab 13 have been designed [o ensure [hat the hydrologic balance is protected. Plans for surface water protection are discussed based on the following parts: 1) surface water quality; 2) surface water quantity; and 3) surface water monitoring. Surface Water quality. Five sediment ponds (Ponds 010,011,012,013 and 014) are proposed to be constructed at the Yoast Mine for controlling surface water runoff from disturbed and reclaimed areas. Water impounded at Ponds 010 and 012 imay be used for dust suppression. All five ponds are proposed as temporary structures, and will be removed and reclaimed after the completion of mining and reclamation activities. Each pond is designed to prevent additional sediment input to the stream flow outside and down gradient • of the permit area, to minimize erosion, and maintain sufficient detention time to ensure all applicable effluent standards are met. Pond discharge structures are designed according to standard engineering design procedures for protection against erosion by installation of riprap. Outlet channels below the ponds are protected from erosion by installing riprap, erosion control mats and reseeding channel banks with temporary seed mixes. The impacts of sediment ponds and runoff from reclaimed areas on the quality of receiving streams was found to be insignificant (see Tab 17, PHC). Upon completion of each temporary sediment pond that discharges to receiving streams, and prior to discharging impounded water, SCC will obtain a modification of the existing NPDES permit (CO 0000221) to incorporate each pond outfall. SCC will properly operate and maintain each NPDES outfall (sediment pond) to insure compliance with the terms and conditions of the NPDES permit during the life of the Yoast Mine. Water quality of discharges from each NPDES outf ell will be of comparable or better quality to discharges monitored historically at NPDES outfalls permitted at both the Seneca II and II-W mines. Significantly fewer exceedences ere expected at proposed Yoast NPDES outf ails, since operational support • activities (e.g. truck washing) and facility areas will be minimal in comparison with the Seneca fI and II•W mines. 4