(225 ILCS 720/4.03) (from Ch. 96 1/2, par. 7904.03)
    Sec. 4.03. Sealing Openings. All portals, entryways, drifts, shafts, or other openings between the surface and underground mine working shall be sealed when no longer needed for the conduct of the underground mining operations.
(Source: P.A. 81-1015.)