4VAC25-130-816.151. Primary roads.
Primary roads shall meet the requirements of 4VAC25-130-816.150 and the additional requirements of this section.
(a) Certification and construction.
(1) The construction or reconstruction of primary roads shall be certified in a report to the division by a qualified registered professional engineer. The report shall indicate that the primary road has been constructed or reconstructed as designed and in accordance with the approved plan.
(2) The centerline of a proposed road shall be flagged prior to field inspection.
(3) All road grades shall be subject to a tolerance of plus or minus 2.0% grade.
(4) Grading. The grade of a road shall not exceed 10% unless a steeper grade is justified by site conditions and topography.
(i) The grade shall be controlled to minimize erosion and sedimentation.
(ii) The road surface shall be sloped toward the ditch line at the minimum rate of ½ inch per foot of width or crowned at the minimum rate of ½ inch per foot of width as measured from the centerline of the road.
(5) Cuts. Cut slopes shall not be steeper than 1v:1.5h in unconsolidated materials, 1v:1h in shale, or 1v:0.25h in sandstone. Steeper slopes may be specifically authorized by the division based on the geotechnical analysis.
(6) Revegetation. All disturbed areas shall be seeded and mulched immediately after construction. If construction occurs during the non-seeding period of November 1 through February 15, the permittee may use alternate methods upon approval by the division for control of erosion. Adequate vegetation to control erosion shall be maintained.
(7) Excess or unsuitable material from excavations shall be disposed of in accordance with 4VAC25-130-816.71. Acid- and toxic-forming material shall be disposed of in accordance with 4VAC25-130-816.41, 4VAC25-130-816.81, and 4VAC25-130-816.102.
(8) Temporary erosion-control measures shall be implemented during construction to minimize sedimentation and erosion until permanent control measures can be established.
(b) Safety factor. The following specifications shall be utilized for embankment construction. The division may specifically authorize alternate specifications if the geotechnical analysis demonstrates that a minimum safety factor of 1.3 can be maintained.
(1) All organic material and topsoil shall be removed from the embankment foundation and no organic material, topsoil, or other unsuitable material shall be placed beneath or in any embankment.
(2) Where an embankment is to be placed on side slopes less than 36%, the following conditions shall be required:
(i) The embankment shall be constructed in uniform, compacted layers not exceeding 4 feet in thickness.
(ii) The embankment slopes shall not be steeper than 1v:1.5h.
(3) Where an embankment is to be placed on side slopes exceeding 36% the following additional conditions shall be required:
(i) A keyway cut shall be constructed at the toe of the fill to ensure stability; the keyway cut shall be at least 10 feet in width and shall be sloped inward.
(ii) The embankment shall be constructed in uniform compacted layers not exceeding two feet in thickness.
(4) Acid-producing materials may be used in the embankments of only those roads constructed or reconstructed on coal mine waste disposal facilities, if it is demonstrated that no additional acid will leave the confines of the facility. In no case shall acid-producing refuse material be used outside the confines of the coal mine waste disposal facility. Restoration of the road shall be in accordance with the requirements of 4VAC25-130-816.102 through 4VAC25-130-816.116.
(c) Location.
(1) To minimize erosion, a primary road shall be located, insofar as practical, on the most stable available surface.
(2) Fords of perennial or intermittent streams by primary roads are prohibited unless they are specifically approved by the division as temporary routes during periods of road construction.
(d) Drainage control. In accordance with the approved plan.
(1) Each primary road shall be constructed or reconstructed, and maintained to have adequate drainage control, using structures such as, but not limited to, bridges, ditches, cross drains, and ditch relief drains. The drainage control system shall be designed to safely pass the peak runoff from a 10-year, six-hour precipitation event, or greater event as specified by the division.
(2) Drainage pipes and culverts shall be installed as designed, and maintained in a free and operating condition and to prevent or control erosion at inlets and outlets.
(i) Sufficient culverts shall be installed to limit erosion in ditchlines. Additional culverts may be required by the division if excessive erosion or sedimentation is anticipated or observed.
(ii) Culverts shall cross the road at not less than a 30° angle downgrade, except if risers are used. Culverts placed in intermittent or perennial streams shall be straight and coincide with normal flow.
(iii) Culverts shall be placed on a minimum 4.0% grade.
(iv) Culverts shall be at least 12 inches in diameter.
(3) Drainage ditches shall be designed to prevent uncontrolled drainage over the road surface and embankment. Trash racks and debris basins shall be installed in the drainage ditches where debris from the drainage area may impair the functions of the drainage and sediment control structures. A ditch shall be provided on both sides of a through-cut and on the inside shoulder of a cut and fill section. Water shall be intercepted before reaching a switch back or large fill and drained safely away. Water from a fill or switchback shall be released below the fill through conduits or in rip rapped channels and shall not be discharged onto the fill. Ditches shall have a minimum constructed depth of one foot, measured from the lowest point in the road surface adjacent to the ditch.
(4) Culverts shall be installed and maintained to sustain the vertical soil pressure, the passive resistance of the foundation, and the weight of vehicles using the road.
(5) Natural stream channels shall not be altered or relocated without the prior approval of the division in accordance with the applicable portions of 4VAC25-130-816.41 through 4VAC25-130-816.43 and 4VAC25-130-816.57.
(6) Except as provided in subdivision (c)(2) of this section, structures for perennial or intermittent stream channel crossings shall be made using bridges, culverts, low-water crossings, or other structures designed, constructed, and maintained using current, prudent engineering practice. The drainage structure itself can be at least equal to or greater than the stream channel capacity immediately upstream and downstream of the crossing. Low-water crossings shall be designed, constructed, and maintained to prevent erosion of the structure or streambed and additional contributions of suspended solids to streamflow.
(7) (i) Sediment control shall be provided as part of the road drainage system unless runoff is diverted to other approved drainage/sediment control structures.
(ii) Sediment control structures along a road shall be designed to provide 0.025 acre-feet of sediment storage capacity for each acre of disturbed area draining to the structure if the structure is the final discharge point for effluent from the permit area. Other capacities may be required by the division.
(e) Surfacing. Primary roads shall be surfaced with rock, crushed stone, gravel, asphalt, or other material approved by the division as being sufficiently durable for the anticipated volume of traffic and the weight and speed of vehicles using the road.
(f) Maintenance. Routine maintenance for primary roads shall include repairs to the road surface, blading, filling potholes and adding replacement gravel or asphalt. Sediment control structures shall be cleaned regularly and when sediment accumulation may impair their functioning. Maintenance shall also include revegetation, brush removal, and minor reconstruction of road segments as necessary.
(g) Coal haulage. Any roads used for transporting coal shall have construction or reconstruction completed prior to the hauling of coal.
Statutory Authority
§§ 45.1-161.3 and 45.1-230 of the Code of Virginia.
Historical Notes
Derived from VR480-03-19 § 816.151, eff. December 15, 1981; amended, eff. June 28, 1982; October 28, 1982; December 14, 1982; October 11, 1983; December 27, 1983; May 8, 1984; June 22, 1984; August 2, 1984; October 16, 1985; January 7, 1987; July 22, 1987; November 25, 1987; October 12, 1988; December 26, 1990; July 1, 1991; July 17, 1991; November 20, 1991; July 7, 1992; May 5, 1993; October 19, 1994; Virginia Register Volume 12, Issue 2, eff. November 15, 1995.