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The segment of McClane Canyon affected by mine surface facilities extends approximately 3000 feet from a box canyon at its upper end to its junction with East Salt Creek. Five tributary drainages come together at the upper end of the canyon to form the main ephemeral drainage. The mine portal facilities are located at this location, and the tributary drainages were diverted via culverts beneath the mine bench when the bench was constructed. The culverts are adequately sized for the design event and have functioned well. A temporary diversion ditch to the south of the sediment pond routes flow from three small ephemeral drainages around the pond, sediment drying area, topsoil stockpile and riprap stockpile. Berms in the office facilities area divert overland flow around the site. Although not addressed th detail in the permit application, an additional diversion of the McClane Canyon stream channel occurred when the access/haul road was constructed in the spring of 1977. The point of diversion is between the riprap storage area and the office area, where the road was constructed across the channel. Due to the placement of road fill in the original channel, the flow in McClane drainage is now routed through a small drainage which flows directly west to East Salt Creek for a distance of approximately 600 feet, rather than to the southwest for approximately 800 feet as it originally did. The diversion channel is approximately four to six feet deep and ten to twelve feet wide at its upper end, underlain by sandstone bedrock, and similar in dimension and appearance to the natwal McClane channel immediately above. Lower segments of the channel have the appearance of a steep sided gully, deeply incised into the colluvial/alluvial deposits, as is typical of ephemeral stream channels in the region. There has apparently been no significant downcutting or associated slumping of gully sides for many years, as there is a mature cover of big sagebrush and greasewood along both edges of the gully for its entire length. Upon final reclamation, all temporary diversion structures will be removed, and ephemeral drainages will be reconstructed in their approximate original locations. The road fill across the lower segment of McClane Drainage will be removed and the approximate original channel configuration will be restored. Diversion design is addressed in Sections 2.4.1 and 2.4.4 of the application. Channel reconstruction is discussed in Section 3.5 of the application. Applicable maps and tables are referenced in the cited text sections. During the renewal review, the Division raised concerns with respect to the diversion of the lower segment of the McClane channel, fmal reclamation drainage configuration, and stabilization of reconstructed channel segments. Most of the concerns were resolved during the course of the review, but certain issues have not been fully resolved, and are addressed in the following stipulations. For certain reclaimed channels, insufficient information regarding design parameters was provided, and concrete slabs were proposed to be used in certain instances to reinforce the channel bottoms. The Division does not consider concrete slabs to be appropriate for use in reclamation of permanent channels, where they would potentially be exposed by concentrated flow, and where other materials more consistent with the surrounding landscape would provide the necessary erosion protection. 15