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<br /> <br />M <br />The Johnson Gulch post-mine channel gradient is close to the pre-mine profile, <br />with some minor exceptions. These exceptions have been anticipated in the <br />approved reconstruction plan foz Johnson Gulch as previously referenced and as <br />included in Appendix P. The steepest portion of [he pre-mine East No Name chan- <br />nel will be reduced in the pos[-mine gradient. Only a small change in the grad- <br />ients of West No Name and Coyote are proposed. The steepest portion of Buzzard <br />drainage profile has shifted downstream for [he post-mine conditions. This area <br />vae mined and regraded prior [o this permit submittal. <br />Hain channel widths prior to mining are generally in the range of 20 feet while <br />the post-mine vidths will be in the range of 50 to 80 feet. This increased vidth <br />vill decrease the post-mine velocities and should enable [he stability of the <br />re-constructed channels to be similar to the non-disturbed channels. Exhibits G, <br />8, 1, J and K of Appendix P gives cross sections of the reclaimed Johnson drain- <br />age. Figures 4.8-3 through 4.8-31 present cross-sections of each of the major <br />drainages to be affected immediately above and below their lower points of dis- <br />turbance. Map H12 shows the locations of these cross-sections and provides fur- <br />ther detail on the morphology of [he drainages following reclamation. <br />Drainages that are regraded after issuance of this permit will have incised chan- <br />nels reconstructed where such channels existed before mining. The channels will <br />be established with a dozer, or similarly effective equipment, to a depth of 1 - <br />2 feet and the width of a blade. During the life of this propose3 permit, <br />incised channels vill be reconstructed in the post-mining drainages of Eas[ and <br />West No Name Gulches in Ashmore Pit. <br />The reconstructed channels will be located in the lower most part of the drain= <br />age. Topsoil will be laid up to the edge of the channels but not in them. <br />4.8.1.4 Sediment Ponds <br />This section contains information on the sediment pond designs. The flood <br />volumes for each drainage are presented first and followed by the dam specifica- <br />tions and information on the spillways. Certified plans for future sedimentation <br />ponds shall be submitted to the division at least 60 days prior to construction <br />of the structure. <br />4-181 <br />