Rule 18.7.229 - UNDERGROUND CROSSING METHODS(1) For crossing existing highways: (a) If practicable, all crossings under existing highways shall be made by boring, pushing or other acceptable trenchless technology.(b) Full controlled-access facility crossings shall be installed by trenchless technology, or other acceptable methods, from control access fence to control access fence. The district can consider exceptions where soils are not suitable for boring or pushing or the length and topography make boring or pushing impracticable. In these cases permission can be granted to install jacking or boring pits within the control access fences. Receiving pits may also be installed in the median to reduce the distance only as a last resort. A traffic control plan must be submitted by the utility and approved by the district prior to beginning work.(c) Trenching through existing paved highways shall be permitted only when installation by boring or pushing pipe is not practicable. When trenching is allowed by the district administrator, installation will be made under the following conditions: (i) The department shall approve the methods used for backfill and compaction and repair of the highway surface where the surface is cut or damaged by utilities' operations. The methods followed shall be consistent with the department's standard practice. Non-shrink backfill may be required by the district as an acceptable alternative to conventional backfill methods.(ii) The department shall be advised of the date work will be started and 12 hours' notice shall be given if this date is changed.(iii) The trenching shall be subject to inspection by the department at all times and upon completion of the project, the department shall inspect and accept the work.(iv) The utility shall be responsible for any repairs necessary as a result of cutting the pavement for a period of 12 months after completion and notice thereof to the department.(d) A traffic control plan shall be submitted by the utility and approved by the district administrator prior to commencing such work.(2) For crossing new highways, facility crossings necessitated by new highway construction shall be built in accordance with the foregoing standards unless the department and utility shall otherwise mutually agree.Eff. 12/31/72; AMD, 1995 MAR p. 1043, Eff. 5/12/95.Sec. 60-3-101 and 60-4-402 MCA; IMP, Sec. 60-3-101 and 60-4-402 MCA;