Ill. Admin. Code tit. 62 § 1817.15
When no longer needed for monitoring or other use approved by the Department upon a finding of no adverse environmental or health and safety effects, or unless approved for transfer as a water well under Section 1817.41, 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 Department, in accordance with Sections 1817.13 and consistent with 30 CFR 75.1711. 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.
Ill. Admin. Code tit. 62, § 1817.15
Amended at 11 Ill. Reg. 8250, effective July 1, 1987