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placed in Pond 11 to create this positive drainage. <br />In addition to the permanent diversion of Coal Creek and Coal Gulch, the Division has approved <br />construction of a riprapped permanent channel diversion beginning at the ephemeral drainage <br />above the Roadside South Mine Portal Bench Area, and extending to the south above the <br />Roadside Refuse Disposal Area (RSRDA) and down along the south end of the RSRDA. This <br />diversion was constructed in 2002. Approval of a permanent diversion of an ephemeral channel <br />draining less than one square mile has also been made for a channel in the vicinity of the Two <br />West Portals reclaimed area. <br />The following Findings 1 -3 apply to the Coal Creek and Coal Gulch diversions and the South <br />Portal area permanent diversion; Finding 4 applies to the Two West Portals permanent diversion. <br />1. The Division has approved permanent diversion of a segment of Coal Creek, a segment of <br />Coal Gulch, and permanent diversion of unnamed ephemeral drainages above the South <br />Mine facilities and the Roadside South Refuse Disposal area. These diversions are <br />consistent with applicable state law, will not diminish downstream water rights, and will <br />meet the requirements of Rules 4.05.4 (4.05.4(4)). <br />2. The permanent diversions shall make use of artificial structural controls in order to allow <br />them to remain in dynamic equilibrium with the drainage basin system. The Division <br />approves the use of rip -rap channel lining along various segments of these channels. <br />3. Channel lining structures and artificial channel roughness structures are proposed for use to <br />control erosion. Artificial structures include a rip -rap transition zone structure in the Coal <br />Creek channel at the location of the former Haul Road 2 crossing, and riprap lining along <br />the South Portal facilities permanent diversion and the Coal Gulch permanent diversion <br />segment. These means were approved by the Division since they are necessary to control <br />erosion, they are stable and will require infrequent maintenance (4.05.4(2)(a)). <br />4. In addition to the permanent diversions mentioned above, a permanent diversion of an <br />ephemeral stream draining less than one square mile has been approved for an unnamed <br />ephemeral tributary to the Colorado River located within the 2 West Portal Disturbance <br />Area. The outside bank closest to the North Portal was built up to prevent the diverted <br />stream from entering the portal. Bedrock lies close to the bottom of the diverted channel <br />and the channel does not require armoring. This decision is based on a fmding that the <br />proposed diversion meets the requirements of 4.05.18 and 4.05.4, applicable local, State, <br />and Federal statutes and regulations and that the diversion is designed to safeguard public <br />safety and to minimize adverse impacts to the hydrologic balance (4.05.4(1) and (4)). <br />D. Sedimentation Ponds <br />Information on the surface water sediment control system can be found in Volume 3, Tab 13, <br />page 13 -5 of the permit application. A list of sediment control structures, along with references <br />to appropriate exhibits for designs and cross sections, are found in Table 13-4 of the application. <br />Calculations used to design these structures are given in appendix 13 -2 of the permit application. <br />During operations a total of 12 sediment ponds were designed and built and have been treating <br />Permit Revision No. 5 24 July 10, 2012 <br />