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Storm runoff from five small areas downhill from the mine's sediment <br />ponds is subjected to alternate treatment prior to leaving the permit area. <br />The five areas are l .) the "material storage area below Pond C, 2.) the <br />pump station, 3.) the topsoil stockpile near the Gob pile, 4.) the cover <br />stockpile near the Gob pile and, 5.) the mine entrance area. <br />The Division granted an exemption from use of sediment ponds for <br />drainage from underground mine workings as long as no mixing with <br />surface drainage will occur and as long as ponds and treatment facilities <br />are not necessary for the drainage to meet effluent limitations of Rule <br />4.05.2 and applicable State and Federal water quality standards for <br />receiving streams (4.05.2(3)(b)(ii)). <br />B. Diversions and Conveyance of Overland Flow <br />The Division does not propose to approve a permanent diversion <br />(4.05.3(2)). <br />2. The Division approved construction of a diversion on an existing landslide <br />(4.05.3(4)). <br />C. Stream Channel Diversions <br />The Division does not propose to approve the diversion of an ephemeral <br />stream draining at least one (1) square mile, an intermittent or a perennial <br />stream (4.05.4(1) and (4)). <br />2. Channel lining structures, retention basins, and artificial channel <br />roughness structures are proposed for use to control erosion. These means <br />were approved by the Division, since they are necessary to control <br />erosion, they are stable and will require infrequent maintenance <br />(4.05.4(2)(a)). <br />D. Sediment Ponds <br />The Division approved alternative design criteria or specifications for use <br />in sediment pond design and/or construction. The gob pile pond (Pond D) <br />has an embankment with slopes steeper than typical requirements. Bowie <br />Resources, Limited provided the required geotechnical stability analyses <br />to justify the implementation of steeper embankment slopes. Sediment <br />pond design details are presented in Section 2.05 and Volume III, Exhibit <br />8 of the permit application document (4.05.6(11)). <br />19 <br />