Section 312 IAC 25-6-130 - Underground mining; primary roadsAuthority: IC 14-34-2-1
Affected: IC 14-34
Sec. 130.
Primary roads shall meet the requirements of section 129 of this rule and the additional requirements of this section as follows:
(1) The construction or reconstruction of primary roads shall be certified in a report to the director by a qualified registered professional engineer with experience in the design and construction of roads. The report shall indicate that the primary road has been constructed or reconstructed as designed and in accordance with the approved plan.(2) Each primary road embankment shall be shown to have a minimum static factor of one and three-tenths (1.3) or shall be designed in compliance with the following design standards:(A) The embankment foundation area shall be cleared of all organic material and the entire foundation surface shall be scarified.(B) If the natural slope of the foundation as measured at a right angle to the roadway center line is steeper than 8h:1v, the embankment shall be benched into the existing slope beginning at the embankment toe and then filled with compacted level lifts.(C) The embankment fill material shall be free of sod, large roots, and other large vegetative matter.(D) The fill shall be brought up in horizontal layers of such thickness as required to facilitate compaction in accordance with prudent construction standards.(E) The moisture content of the embankment shall be sufficient to secure proper compaction.(F) The side slope of the embankment shall be no steeper than 2h:v1.(G) Maximum fill height shall be twenty-five (25) feet as measured from the natural ground at the downstream toe to the top of the embankment.(H) The embankment shall have a minimum top with of (h + 35)/5, where "h" is the embankment height as measured from natural ground at the downstream toe to the top of the embankment and shall be adequate for the intended use.(3) The location of primary roads shall be established in accordance with the following provisions: (A) To minimize erosion, a primary road shall be located, insofar as is practicable, on the most stable available surface.(B) Fords of intermittent streams that drain a watershed of at least one (1) square mile or perennial streams by primary roads are prohibited unless they are specifically approved by the director as temporary routes during periods of road construction.(4) In accordance with the approved plan, drainage shall be controlled as follows: (A) Each primary road shall be constructed or reconstructed, and maintained to have adequate drainage control, using structures such as, but not limited to, the following: (iv) Ditch relief drains.(B) The drainage control system shall be designed to safely pass the peak run-off from a ten (10) year, six (6) hour precipitation event, or greater event as specified by the director as follows: (i) 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.(ii) Drainage ditches shall be constructed and maintained to prevent uncontrolled drainage over the road surface and embankment.(iii) Culverts shall be installed and maintained to sustain each of the following: (AA) Vertical soil pressure.(BB) Passive resistance of the foundation.(CC) The weight of vehicles using the road. (C) Natural stream channels shall not be altered or relocated without the prior approval of the director in accordance with the applicable portions of sections 77 through 83 and 91 of this rule.(D) Except as provided in subdivision (3)(B), 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 practices. The director shall ensure that low water crossings are designed, constructed, and maintained to prevent erosion of the structure or streambed and additional contributions of suspended solids to stream flow.(5) Primary roads shall be surfaced with material approved by the director as being sufficiently durable for the anticipated volume of traffic and the weight and speed of vehicles using the road.Natural Resources Commission; 312 IAC 25-6-130; filed Jun 21, 2001, 2:53 p.m.: 24 IR 3582, eff Dec 1, 2001; filed Apr 1, 2004, 3:00 p.m.: 27 IR 2467, eff Jan 1, 2005; readopted filed May 29, 2007, 9:51 a.m.: 20070613-IR-312070146RFA; readopted filed Sep 19, 2013, 10:12 a.m.: 20131016-IR-312130125RFAReadopted filed 3/26/2019, 3:40 p.m.: 20190424-IR-312190011RFA