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<br /> <br /> <br /> 28 C1981-041 RN7 findings <br />Ponds 6 and 10 were backfilled and graded, as depicted in Exhibit 9C, so as not to disturb <br />the current alignment of Coal Canyon. The reclamation plan of Pond 6 included placement <br />of more fill along the toe of CRDA #1, providing additional protection from any possible <br />cutting into the refuse pile. See Appendix 13-2, pages Misc. 13 through Misc. 19 of the <br />permit document for details of the current Coal Canyon Runoff and Drainage design. The <br />design information shows that the diversion drains a watershed greater than one square <br />mile and has been appropriately designed to pass safely the peak runoff of a 100-year 24- <br />hour event. <br /> <br />A second permanent channel diversion has been approved for the lower segment of Coal <br />Gulch in the vicinity of Sediment Pond 11. The pond 11 embankment is located <br />immediately northwest of Coal Gulch. A small portion of this embankment was removed <br />so pond 11 is opened to Coal Gulch. The embankment material and another 3,500 cubic <br />yards from topsoil stockpile number 1 was placed in Pond 11. This material was used to <br />create a positive 0.5% grade so the reclaimed pond 11 area drains to Coal Gulch. Three to <br />five feet of fill was placed in Pond 11 to create this positive drainage. <br /> <br />In addition to the permanent diversion of Coal Creek and Coal Gulch, the Division has <br />approved construction of a riprapped permanent channel diversion beginning at the <br />ephemeral drainage above the Roadside South Mine Portal Bench Area, and extending to <br />the south above the Roadside Refuse Disposal Area (RSRDA) and down along the south <br />end of the RSRDA. This diversion was constructed in 2002. Approval of a permanent <br />diversion of an ephemeral channel draining less than one square mile has also been made <br />for a channel in the vicinity of the Two West Portals reclaimed area. <br /> <br />The following Findings 1-3 apply to the Coal Creek and Coal Gulch diversions and the <br />South Portal area permanent diversion; Finding 4 applies to the Two West Portals <br />permanent diversion. <br /> <br />1. The Division has approved permanent diversion of a segment of Coal Creek, a <br />segment of Coal Gulch, and permanent diversion of unnamed ephemeral drainages <br />above the South Mine facilities and the Roadside South Refuse Disposal area. These <br />diversions are consistent with applicable state law, will not diminish downstream <br />water rights, and will meet the requirements of Rules 4.05.4 (4.05.4(4)). <br /> <br />2. The permanent diversions shall make use of artificial structural controls in order to <br />allow them to remain in dynamic equilibrium with the drainage basin system. The <br />Division approves the use of rip-rap channel lining along various segments of these <br />channels. <br /> <br />3. Channel lining structures and artificial channel roughness structures are proposed for <br />use to control erosion. Artificial structures include a rip-rap transition zone structure <br />in the Coal Creek channel at the location of the former Haul Road 2 crossing, and <br />riprap lining along the South Portal facilities permanent diversion and the Coal Gulch <br />permanent diversion segment. These means were approved by the Division since <br />they are necessary to control erosion, they are stable and will require infrequent