Laserfiche WebLink
Hydrologic design documentation for road ditches and culverts is provided in Exhibit 2.05.3 -E2, <br />Drainage and Sediment Control Plan. The ditches and culverts are designed and constructed in <br />accordance with Rule 4.03.1(4). Little Grassy Creek is conveyed under Road B -1 (at approximately <br />Station 2 +35) through Culvert 15A; the culvert has been designed to safely pass the peak runoff <br />from the 25 -year, 24 -hour storm event in accordance with Rule 4.03.1(4)(e)(i). <br />Access Roads - Access roads are frequently traveled roads not used for haulage operations and <br />include activities such as supervision of mining operations and /or servicing of major facilities; <br />access roads include: <br />• Road C <br />• Road E -1 <br />Access road layouts are shown on Map 2.05.3 M3, Map 2.05.3 M1A and Map 2.05.3 M1B. <br />Access to the South Facilities and Portal Area by non -coal haulage traffic will generally be over <br />Road A/B. While this road is classified as a haul road, it will be the primary access to the south <br />facilities area and will be utilized for vehicular access by mine employees and visitors, and for any <br />materials and supplies being delivered to the mine to support mining and related operations. <br />Although the posted speed limit for access roads will be 25 mph, road horizontal alignment is based <br />on a 40 mph design speed, for safety reasons. Horizontal and vertical alignment have been <br />carefully coordinated so that no horizontal curve begins or ends at the crest or sag of a vertical <br />curve, and in such a manner as to comply with regulatory cross -slope and grade requirements, <br />control erosion, simplify drainage design, and maximize safety and environmental protection. <br />Centerline profiles of the access roads are presented on Map 2.05.3 M3. A schematic showing the <br />typical cross section is shown below as Figure 2.05.3 -F2, Typical Access Road Cross - Section. <br />All access roads will be constructed in accordance with Rule 4.05.2. Typical construction practices <br />for access roads will involve implementing temporary drainage and sediment control measures, <br />clearing and grubbing vegetation (limited to the width needed for the roadway and drainage <br />control), and recovery and stockpiling of available soil materials. All soil material recovered from <br />roads and other areas will be placed in the topsoil stockpile located adjacent to PECOCO Pond. <br />Mine access roads will be constructed with a minimum of 36 inches of compacted road base <br />material, topped with a 12 -inch gravel base, and 6 inches of gravel surfacing or 4 -5 inches of <br />asphalt. No potentially acid- and /or toxic - forming or frozen materials will be utilized in either road <br />fill construction or as road surfacing materials. <br />TR -0?' 2.05 -25 Revision 4/12 <br />