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The diversion charnel will be at a grade of 5 to 7 percent. It <br />• <br />o-:ill be reinforced with raprap and/or other structures at these locations <br />where it intersects natural drainage channels. Excavated materials will <br />not be sidecast, but stockpiled or used elsewhere at tiie mine. <br />At each end, the proposed channel will be widened if necessary to <br />reduce flew velocities. Energy dissipators and drop structures with a <br />capacity to control a~l•OO~ye~o~event will also be constructed. <br />Qeyond this, adequate spillway capacity will be provided to pass the <br />p'~TS. The channels in the receiving ~:~atersheds will be heavily riprapped <br />just downstream from the diversion channel so that scouring activity is <br />kept to a minimum. <br />The contribution of sediment from the diversion channel is expected <br />• <br />to be small except for major flood events. The channel will be maintained <br />or, a regular basis to prevent accumulations of debris and sediment from <br />entering the receiving watersheds during subsequent runoff. <br />It is expected that the diversion channel will become a permanent <br />feature on the landscape. The maintenance program will be designed to <br />Beet this objective. After mine operations cease, Cl•lI will continue to <br />ensure its hydrologic integrity by routine maintenance. <br />As o-,~ith the diversion channel, storm runoff discharges frnm the lo~•~er <br />basin will be controlled to prevent scouring in the receiving watersheds. <br />Introduced sediment will be kept to a minimum through a vigorous reclama- <br />tion and maintenance program at the mine site, and the maintenance of <br />adequate buffer strips where possible to prevent the direct introductior. <br />of sediment into stream channels. <br />I• <br />