Sec. 26.20.13.03. Permanent Casing and Sealing of Underground Openings

A. Unless excepted under §B of this regulation, each shaft, drift, adit tunnel, exploratory hole, entryway, or other opening to the surface from underground shall be capped, sealed, backfilled, or otherwise properly managed, as required by the Bureau. Permanent closure measures shall be designed to prevent access to the mine workings by people, livestock, fish and wildlife, and machinery, and to keep acid or other toxic drainage from entering ground or surface waters.

B. Permanent closure may not be required where an opening is needed for monitoring purposes, or is approved for transfer as a water well or some other use upon a showing of no adverse environmental or health and safety effects. Bureau approval shall be required for all these exceptions.

C. Mine opening seals shall be:

(1) Designed using the best technology currently available and certified by a qualified registered professional engineer; and

(2) Certified after construction by a qualified registered professional engineer as having been constructed according to the approved design.