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All of the original roads that cross the New Horizon Mine will be restored to original conditions and <br />Montrose County standards. Per the request of Cal Benson, the portion of the BB Detour Road <br />on his property will be left in place. A letter to that affect is attached to this section <br />Postmining Drainage Channels <br />All major drainages in the New Horizon 2 area that are to be disturbed by mining activities will be <br />reclaimed to approximate the premining configuration and to blend with the undisturbed drainage <br />above and below the area to be reclaimed. Two pre- mining channels are encountered and <br />restored. These are called the Krill Channel, on the easternmost portion of the mined area, and the <br />San Miguel Channel, which drains into the reclaimed area of Pond 007. Both of these channels are <br />shown on Map 2.05.3(3) -1 Surface Hydrology. The post- mining drainage channels will be designed, <br />constructed, and maintained to the following specifications: <br />1. Gentle sloping banks which shall be stabilized by vegetation; <br />2. Prevent additional contributions of suspended solids to streamflow and to runoff <br />outside the permit area; <br />3. Blend with the undisturbed drainage above and below the area to be reclaimed; <br />4. Safely pass the runoff from a 10 -year, 24 -hour precipitation event. <br />The reclaimed drainages are designed to safely pass the 10 -year, 24 -hour precipitation event and <br />to be stable. The peak flow was determined by using the SEDCAD+ Version 3.0 computer <br />program. A listing of the input parameters for obtaining the peak flows for the reclaimed drainage <br />channels are shown in the appropriate channel attachment. The peak flow determination assumed <br />the total watershed of the reclaimed channel and was determined at the downstream end of the <br />channel. Most of the reclaimed channel will not have to handle that large a peak flow rate. This <br />was done to ensure that the drainage channel capacity will be adequate and yet conservatively <br />designed. <br />(Revised June 2010) 2.05.4(2)(c) -11 <br />