Laserfiche WebLink
o Due to the proximity of the road to the highwall, the Division recommends that the operator <br />place a safety berm that runs parallel between the road and the highwall. Please incorporate a <br />safety berm into the plan, provide dimensions of the berm and include on the applicable <br />maps. <br />20. The operator states that where the roadway crosses Taylor Gulch, arip-rapped jeep trail crossing of <br />the drainage will be maintained for 4wd access. Across the channel, the crossing will have a 3-foot <br />high rip-rap berms on either side of the crossing roadway to ensure separation of Taylor Gulch <br />drainage from the mine drainage. The Division has the following comments/questions regazding this <br />crossing; <br />o Please explain how vehicles (mining related vehicles and vehicles owned by the public) will <br />be able to traverse the 3-foot high beans in order to cross the drainage. Has the operation <br />considered installing a culvert to safely pass the flows of Taylor Gulch while maintaining the <br />road? <br />o If the operator plans on relocating the road on the west end of the permit area, please explain <br />the need of the existing road that crosses Taylor Gulch. <br />o Please include the 3-foot high berms in the drainage cross-section diagram. <br />o Please reference the location of the cross-section on the mine plan map. <br />21. The operator states that roads will drain water into the lower pit elevation with constructed road <br />ditches. Please specify these roads and ditches on the mine plan map and describe how such drainage <br />will end up in the lower pit area. Ditch designs and cross sections must be provided. <br />22. The operator proposes a waste rock berm along the western side of Taylor Gulch to ensure that Taylor <br />Gulch drainage is separate from the mine drainage. The Division has the following comments/ <br />questions regazding the waste-rock berm; <br />o Exhibit Cc notes the berm crossing over Road 228. How will the berm be maintained to <br />facilitate the access of vehicles while also preventing water from entering Taylor Gulch? <br />o It is unclear how the water will ultimately drain into the lower pit area. There is no defined <br />drainage ditch leading into the pit and the contours on the map suggest that drainage will flow <br />to the east, ultimately into Taylor Gulch. Please demonstrate how mine water and sediment <br />will be directed into the lowest pit area and specify the anticipated flows that will be <br />encountered. Tn addition, provide documentation to support that the drainage system can <br />handle the anticipated flows. <br />o The waste berm appears to be directed along the toe of the waste rack pile and will intersect <br />Road 228 at the south end, of the permit area. This portion of the berm is well below the <br />Lowest elevation of the pit, and will direct mine water directly on to Road 228 and eventually <br />off site. Please address how mine water runoff from the south and east of the lowest pit area <br />will be managed to prevent off site damage and minimize impacts to the hydrologic balance. <br />23. The drainage Swale on the west side of the highwall runs the entire length of the highwall until it <br />crosses the proposed reconstructed road and enters the lowest pit elevation. The Division has the <br />following comments/ questions regazding the west highwall drainage ditch; <br />o The operator states that the ditch will be constructed to a 1% grade. However, according to <br />Exhibit Cc, the ditch will be over 3,000 lineaz feet at a 22% grade. Please explain this <br />apparent discrepancy. <br />