2011-01-13_PERMIT FILE - C1981038A (6)

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2.05 APPLICATION FOR PERMIT FOR SURFACE OR UNDERGROUND MINING ACTIVITIES - MINIMUM REQUIREMENTS FOR OPERATION AND RECLAMATION PLANS. Rip-rap will be placed as follows: for maximum flow in low flow channel of 6 feet/second bottom velocity, stones at least 6 inches in diameter will be used for the entire length; for high flow conditions of 10 feet/second in order to maintain stability, rip-rap will be at least 18 inches in diameter at both ends of the channel for a distance of 75 feet from the outfall. One-half of the rip-rap will be 14 inches in diameter or greater. All outside bends in the large channel will also be rip-rapped with rock of this size. As specified by BLM, gabions and rip-rap will be used to protect the receiving watershed at the east end. Rip-rap, at least 18 inches in diameter, will be placed in the receiving watershed at the west end. Gabions and/or rip-rap will extend at least 35 feet beyond each end. Excess excavated material has been used to re-grade the timber storage area southwest of the mine site. Suitable unconsolidated material (subsoil) has been used to repair washout areas and to further promote the re-vegetation efforts throughout the mine site. Topsoil has been removed, stored, and reused for re-vegetative efforts along the channel. Areas to store topsoil have been designated and marked for temporary use. See Map 8-1 for location of existing topsoil storage areas. An auxiliary diversion ditch was constructed to protect the disturbed area in case of main diversion channel instability. It is 856 feet in length and was constructed during the Fall, 1982. The ditch, which traverses the outside edge of the fan level, empties into the large diversion ditch drainages on each end of the bench. The auxiliary ditch carries drainage from the fan level bench and serves as a back-up system for the large diversion ditch. The ditch was constructed during an extensive drainage reconstruction project of the fan and crushing and screening levels, which took place during the Fall, 1962, and Summer, 1983. Small landslide areas on the fan level cut slope were repaired, the fan level bench was re-graded, a berm was constructed on the outside edge of the bench, and the auxiliary ditch was constructed during late Fall, 1982. The drainage reconstruction, as well as the addition of the auxiliary ditch were recommended in the Phase II Stability Analysis studies by Geo-Hydro Consulting, Inc., and Merrick and Company (see Volume 6). Designs by the applicant's engineers for the landslide repair and auxiliary ditch construction may be seen in the Diversion Appendix in Volume 8A. ~~ Permit Renewal - 26 - /~N-Oy ~4/R/O4~ /'72-~06 01/03