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Section - 2.05.3 <br />installation of drainage structures, grading, and placement of surfacing materials. Topsoil is generally <br />not recovered for Gght-use roads in steep terrain, where sidecast construction is necessary, due to <br />• practical operational and safer}' considerations. For haul roads, fill and embankment construction <br />involves placement and compaction of fill materials in horizontal lifts approximately 12 inches deep <br />over the width of fill or embankment. When rock or rocky material is used for fills, lifts do not <br />exceed the maximum size of the rock present, and in no case exceed 30 inches in depth. Cut/fill and <br />any required borrow activities are conducted to specifically avoid inclusion of any vegetation, organic <br />materials, soils, coal slack, wet or frozen materials, and potential acid-or toxic-forming materials in <br />road fills and surfacing materials. Each lift is moistened, if necessary, to achieve optimal compaction <br />and construction or compaction equipment is run back and forth over the fill until the design <br />compacrion of not less than 90 percent of maximum unit dry weight is achieved. Compaction is <br />carried to the edge of the fills so that final embankment slopes aze firm and sable. Where fills are <br />placed on existing slopes which are steeper than SH:1V, the slopes are benched and scazifled and the <br />loosened material blended with the fill during placement and compaction. <br />Temporary erosion and sediment control measures are implemented during road construction to <br />control runoff, sediment loss, and sediment transport from the associated disturbed aeeas. Such <br />measures include the use of temporary berms and ditches and placement of silt fence and/or straw <br />bales to in[ercept and control drainage. Drainage ditches are provided at the toe of all cut slopes and <br />at other locations along the road alignment, as required to effectively control erosion and runoff <br />flows. Where ditch installation is required, ditches aze cut to the design configuration and grade <br />following completion of road construction. On completion of road ditches to the design <br />configuration and grade, riprap or other erosion conuol materials (if required) aze placed to limit <br />erosion and control flow velocities. Culvert installation involves excavation to competent material; <br />placement of bedding material; culvert installation; placement and compaction of fill and cover <br />material around and over the culvert; and placement of appropriate headwall and outlet protection, <br />where required. On completion of road construction, associated cut slopes and embankment <br />• outslopes are seeded and mulched to stabilize the slopes and minimize erosion potential. <br />All roads are designed and constructed to prevent ponding of water on the road surface. This <br />typically involves establishing a smooth graded surface that slopes back into the hillside so that any <br />surface runoff flows to the designed road drainage ditches. Because they are used on a regulaz basis, <br />haul and access roads are typically surfaced with from two to six inches of gravel, or crushed road- <br />base material. Light-use roads are typically surfaced with either suitable granular material or a thin {0- <br />2 inches) layer of gravel or crushed road-base material Road maintenance normally involves periodic <br />grading, watering to control dust, placemem of additional surfacing material, clean-out of road dkches <br />and culverts, and repair of any significant erosion or damage. On completion of mining, any roads <br />not required to support ongoing or anticipated future operations and not approved as permanent <br />roads to support postmining land uses will be removed and reclaimed, as described in Section 2.05.4. <br />Ponds. Imnoundments and Diversions <br />General plans including descriptions, maps, and cross-sections, as appropriate, are presented in the <br />following sections. As appropriate and required, design information has been certified. Analysis of <br />potential subsidence effects is not required since all designed structures are located outside of potential <br />subsidence areas. <br />Detailed design plans including any required geotechnical investigations, descriptions of operating and <br />maintenance requirements, and removal/reclamation requirements are described or referenced in the <br />following sections. These plans are designed to effect full compliance with applicable provisions of <br />Rule 4.05. Specific design requirements for large reservoirs, sedimentation ponds, temporary and <br />permanent impoundments, and stream channel diversions aze addressed by discussion or reference in <br />• the following sections. <br />TR-43 2.05-32 Revised August 2003 <br />