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culverts. Scour protection was provided at the outlet of the culverts. Pursuant to TR-42 <br /> approved in 2003, the Division approved the installation of a riprap transition zone at a <br /> "nick-point" in a lower segment of the Coal Creek channel, in the vicinity of the former <br /> Haul Road 2 channel crossing.Approximately 700-feet downstream of the double culverts, <br /> a transition zone was installed. See Exhibit 8B and Appendix 13-2,pages Misc-13 through <br /> Misc-22 of the permit document for details of the scour protection and transition zone. <br /> Scour protection was installed at the outlet of the upper dip section during 2002. <br /> Sections of the Coal Canyon permanent channel diversion near Ponds 6 and 10, and the <br /> Coal Gulch drainage in the vicinity of Pond 11 were originally planned and approved by <br /> the Division to be re-aligned and modified in conjunction with removal of the ponds. The <br /> Coal Gulch and sections of Coal Canyon drainage were going to be diverted back through <br /> the pond locations which would approximate these drainages original configuration. <br /> However, during a meeting between SCC and the U S Corp of Engineers it was <br /> recommended that Coal Canyon drainage,which was previously approved for realignment <br /> during the reclamation of Ponds 6 and 10, remain in its current configuration. The re- <br /> routing of the Coal Canyon and Coal Gulch drainages would require a permit from the U <br /> S Corp of Engineers. Carrie Sheate of the US Corp of Engineers proposed that realignment <br /> of Coal Canyon for the sake of routing the drainage back to its original contours would not <br /> be a justifiable reason for issuing a Corp Permit. The Division concurred with not re- <br /> disturbing the current alignment of Coal Canyon and Coal Gulch and approved PR-5 <br /> leaving these drainages in their present alignment and configuration. Coal Canyon drainage <br /> and Coal Gulch are stable in their current position. <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 91, 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 /> 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 I embankment is located <br /> immediately northwest of Coal Gulch. A small portion of this embankment was removed <br /> so pond I I 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 I I area drains to Coal Gulch. Three to <br /> five feet of fill was placed in Pond I I to create this positive drainage. <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 /> 25 <br />