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Section B - Findinss and Specific Approvals Required by Rule 4 Section 2.07.6(2)(m) requires that the Division make all specific approvals required in Rule 4 prior to approving a permit. The following findings and specific approvals aze required by Rule 4. I. Roads -Rule 4.03 The applicant presents a discussion of roads in Section 4.03 of Volume 2 of the permit application. Road locations and designs are presented in Exhibit 17 and on Map 27. The Division reviewed these designs for compliance with the design and performance standazds of Rule 4.03. There aze approximately 1.8 miles of haul road, 3.0 miles of access road, and 2.5 miles of light-use roads. Most roads found at the Eagle Mines aze located on gentle slopes of less than 5 percent grade. Only light-use roads which give access to monitoring sites aze found on steeper slopes. The operator is not proposing any new roads. All roads are existing structures. The design report prepared by C.T.L. Thompson (Exhibit 17) demonstrates that the existing roads were designed with sound engineering practices and aze structurally stable. For the purpose of examining road cuts and road embankment conditions, the operator looked at the worst-case road segments at the mine. The roads at the mine were designed for proper road drainage as well as compatibility with the sediment control system. A few access and light-use road segments did not require roadside drainage ditches to collect runoff due to the fact that the grade is only two to five percent. An example is the access road on the southeast edge of the surface facilities area. Roads were pitched to allow sheet runoffto disperse into adjacent grassland. On steeper roads, roadside drainage ditches aze used to collect runoff and safely dischazge it. Much of the runoff from the roads is passed through a sedimentation pond to decrease suspended solids. Culverts are provided at intersections with drainage channels so as not to interfere with the natural stream flows. The operator's design for the road bridge that crosses the Williams Fork River indicates the bridge will safely pass the river flow resulting from a 100-yeaz storm event. One vaziance from the road drainage requirements is granted to the applicant. Rules 4.03.1(4)(e) and 4.03.2(4)(e) contain specific requirements for culvert spacing to dischazge water at periodic intervals from the mine roads. The Division has not required RAG Empire Corporation to adhere to these spacing requirements. The roads aze existing structures built before this requirement was implemented. The roads either discharge water as sheet flow or into a roadside ditch that has been designed to handle the runoff generated by a 10-yeaz, 24-hour precipitation event. For these reasons, additional road drainage culverts were not required. 16