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structures and provide one map which depicts all culverts, ponds, and ditch locations <br />on site. In 2006 WFC prepared Technical Revision No. 54 (TR -54) to include a <br />complete inventory of all surface water control structures and a complete new list of <br />culverts, collection ditches and diversions for the permit area. TR -54 was approved in <br />July 2007 and included new Map 2.05.3(3) -1, Surface Water Hydrology (Surface <br />Water Features and Controls). <br />The updated information with TR -54 incorporated the latest topography for the site <br />and essentially all designs east of 2700 Road show the post- mining topography design, <br />while the area west of 2700 Road used the worst case drainage scenarios so that the <br />structures are conservatively designed. Collection ditches, culverts, and diversion <br />design parameters are described in Section 2.05.3(3) Mine Facilities pages 2.05.3(3) -8 <br />through 10 and detailed design information is given in Attachment 2.05.3(3) -1 <br />Collection/Diversion Ditches and Culverts Design Parameters. <br />With PR -6, the permit was updated to reflect the surface water hydrology for all <br />disturbed areas and those which have been reclaimed. Map 2.05.3(3) -1 of the permit <br />illustrates the topography, ponds, and ditches. <br />C. Stream Channel Diversions <br />There are no stream channel diversions proposed for the New Horizon Mine. <br />Calamity Draw flows undisturbed parallel to the NH Mine 2 southern boundary, while <br />Tuttle Draw parallels the northern boundary. <br />D. Sedimentation Ponds <br />WFC uses sediment ponds to prevent additional contributions of sediment to <br />streamflow or runoff outside the permit area due to mining disturbances. Sediment <br />pond locations are shown on Map 2.05.3(3) -1. Sediment pond design, construction <br />and maintenance are described in Section 2.05.3(3) Mine Facilities of the permit <br />application package. The pond designs and runoff calculations for the permit area <br />ponds are shown in the following attachments: Pond 007 Attachment 2.05.3(3) -2; <br />Pond 008 Attachment 2.05.3(3) -4; Pond 009 Attachment 2.05.3(3) -5; Ponds 10 & 13 <br />Attachment 2.05.3(3) -6; Pond 011 Attachment 2.05.3(3) -14; Pond 012 Attachment <br />2.05.3(3) -12 and 13; Pond 014 Attachment 2.05.3(3) -11; and Pond 015 Attachment <br />2.05.3(3) -20. <br />Pond 010 has an approved design but this pond was never constructed. Ponds 007 and <br />008 are currently the only ponds that will remain as permanent impoundments after <br />reclamation. The approved demonstrations to allow retention of Pond 007 and 008 are <br />in Attachments 2.05.3(3) -16 and 2.05.3(3) -19, respectively. <br />Alternative design criteria and specifications have been approved for use in sediment <br />pond design and /or construction. This decision is based on a thorough analytical <br />demonstration by a qualified professional engineer that the resulting sediment pond <br />