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20-year, 24-hour peak flow. The permittee installed inlet transitions in order to pass the event. <br />Designs for proposed new Access Road 1 A were provided in PR-3 (see narrative on page 13-3 i and <br />Table 13 page T13-2-6, location diagram on page A14-5-30, embankment stability analysis within <br />Appendix 14-8, and additional design and location information on Exhibits 6C, 6C-A, and 26). <br />Access Road IA will be constructed on Snowcap Coai Company property in association with <br />reclamation work necessary to implement the altemative "Industrial or Commercial" postmining land <br />use. The road will be located to the west of existing Access Road 1, and will provide access to the <br />mine bench repair shop, storage, and parking areas following completion of reclamation. The road <br />will be constructed in accordance with the design and construction criteria of Rule 4.03.2(3), <br />applicable to road segments that are not located within "disturbed areas", and will replace the segment <br />of Access Road 1 between the lower parking area and the mine bench. The segment ofAccess Road 1 <br />between the lower parking area and the mine bench will be reclaimed. Access Road 1 A and a short <br />upper segment of Access Road I (approximately 100 feet in length) will be retained for the alternative <br />postmining land use. The segment of Access Road 1 to be retained will provide access to proposed <br />equipment storage azeas located on the flat top of the RSRDA waste disposal site. <br />Three dip-sections were installed along coal creek during construction of Haul Roads 2, 3 and 4. The <br />two upper dip-sections have six 36-inch CMP culverts laid side by side and incased in concrete. In the <br />concrete, they have an end area greater than 35 square feet, therefore, they must pass the 20-year, <br />24-hour peak flow to be in compliance with Rule 4.03.1(4)(e)(i). The lower dip section is only <br />required to pass the 10-year, 24-hour peak flow to be in compliance with Rule 4.03.1(4)(e)(i). <br />Designs reveal that the dip-sections will not pass the design peak flows without overtopping. <br />In 1982, the petmittee submitted justification that the dip-sections would be as environmentally sound <br />as designs which would comply with Rule 4.03.1(4)(e)(i). Since the dip-sections are constructed of <br />reinforced concrete, they will not erode if overtopped. In addition, the upstream and downstream <br />sections of the stream aze protected by riprap so they will not be undermined. The overtopping of the <br />dip-sections will likely be a gradual event. The water will flow over the top of the smooth concrete <br />surface with very little turbulence being induced by the dip-section. According to calculations done <br />by the permittee, the dip-sections would be overtopped for a total of 3.4 hours during a 20-year, <br />24-hour precipitation event. The installations are therefore acceptable to the Division. <br />[n conjunction with reclamation activities within each of the surface facilities areas, a number of roads <br />will be removed and restored to approximate original condition. All culverts will be removed, natural <br />drainage patterns across each road will be reestablished, and all disturbed areas will be revegetated. <br />Certain roads will be retained for postmining use, in accordance with landowner requests for use <br />following completion of mining and reclamation. Road retention narrative and documentation is <br />provided on Page 14-14 and in Appendix 14-5. New Access Road lA to be constructed upon <br />approval of PR-3 will be retained in its entirety for the altemative postmining land use, as will a short <br />upper segment of existing Access Road I . Landowner request for retention of these road segments is <br />provided on Appendix pages A 14-5-29 and A 14-29-30. In addition to the haul road and access road <br />segments specified below, portions of Light Use Road 1 and Light Use Road 6, which were pre- <br />existing, minimally modified and used only occasionally by the operator, will be retained following <br />reclamation in accordance with landowner requests. <br />A. Haul Roads <br />Permit Revision No. 3 <br />July 30, 2007 <br />Permit No. C-1981-041 <br />Page 20 <br />