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B. Diversions and Conveyance of Overland Flow <br /> 1. All conveyance structures within the permit area are designed and constructed in <br /> accordance with Rule 4.05.3. Permanent diversions above coal mine waste banks are <br /> designed and constructed in accordance with Rule 4.09.2(7). Table 13-4 of the application <br /> lists all diversion and conveyance ditches along with references to the appropriate exhibits <br /> for designs and cross sections. Calculations used to design these structures are given in <br /> appendix 13-2 of the permit application. A number of permanent channels or channel <br /> segments have been constructed or will be constructed following reclamation of temporary <br /> sediment and drainage control facilities at various locations. As described in greater detail <br /> below the Division has approved four permanent channel diversions located in Coal <br /> Canyon, Coal Gulch, at the ephemeral drainage above the Roadside South Mine Portal <br /> Bench Area, and at an ephemeral channel in the vicinity of the Two West Portals reclaimed <br /> area. A permanent reconstructed channel segment has been completed at the North <br /> Decline Reclaimed area, in accordance with the approved plan channel berm breaks have <br /> been installed. Several permanent ephemeral channels were constructed across the North <br /> Portal reclaimed area. The final channel designs were completed with approval of PR-5. <br /> The channels are shown on Exhibit 8C Roadside North Portal Post Mining Topography. <br /> As part of the redesign the West Diversion Ditch and the East Diversion Ditch will remain <br /> as permanent post-mine features. Pond 13 was reclaimed when the final ephemeral <br /> drainages were constructed in 2012. Finally, several permanent drainage channels were <br /> constructed in association with the South Portal area reclamation grading. <br /> C. Stream Channel Diversions <br /> Construction of the Cameo Refuse Disposal Areas involved the installation of a permanent <br /> ephemeral stream channel diversion along a segment of Coal Canyon in the vicinity of the <br /> refuse areas. A total of approximately 600 feet of the Coal Canyon drainage was diverted. <br /> As part of the design for CRDA-2, the Coal Canyon drainage channel was realigned to <br /> provide a more uniform, controlled flow between CRDA I and 2. The four rock check <br /> dams constructed in the channel have caused significant deposition and necessitated <br /> frequent maintenance. In order to assure the channel is in equilibrium with the flow regime, <br /> the rock check dams were removed and the excess sediment was harvested and used as <br /> refuse cover soil during the 2002 reclamation project. The drainage channel was graded to <br /> an approximate uniform grade to the cross sections presented on Exhibits 53 and 55 of the <br /> permit document. Berms located along the middle and lower sections were leveled so the <br /> channel blends naturally into the adjacent terrain. Berms are not utilized to provide the <br /> necessary flow capacity along the segment between the dip section concrete structure at <br /> the upper end and the two 81" by 59" culverts at the lower. Additionally, the Pond 6 <br /> embankment was built up and fortified with riprap. The rock from the check dams was <br /> used for the construction of rock groups placed on the reclaimed surface of CRDA-1 & 2 <br /> and other reclamation uses. Since material generated from the Coal Canyon Realignment <br /> was utilized for the reclamation of CRDA-2, the realignment was performed concurrently <br /> with the 2002 refuse pile reclamation project. <br /> During 2003, work was performed in Coal Canyon below the outlets of the large double <br /> 24 <br />