(225 ILCS 720/3.23) (from Ch. 96 1/2, par. 7903.23)
    Sec. 3.23. Steep-Slope Mining. (a) This Section applies to steep-slope surface mining. A steep slope is a slope greater than 20 degrees. The standards set forth in this Section are in addition to the other performance standards set forth in this Act. This Section does not apply where an operator is mining on flat or gently rolling terrain, on which occasional steep slope is encountered through which the mining operation is to proceed, leaving a plain or predominantly flat area.
    (b) When surface mining is performed on steep slopes, no debris, abandoned or disabled equipment, spoil material, or waste mineral matter shall be placed on the downslope below the bench or mining cut. Spoil material in excess of that required for the reconstruction of the approximate original contour under the provisions of Section 3.04 shall be permanently stored in accordance with Section 3.17.
    (c) Complete backfilling with spoil material shall be required to cover completely the highwall and return the site to the appropriate original contour, which material will maintain stability following mining and reclamation.
    (d) The operator may not disturb land above the top of the highwall unless the Department finds that such disturbance will facilitate compliance with the applicable performance standards of this Act. The land disturbed above the highwall shall be limited to that amount necessary to facilitate said compliance.
    (e) The Department may allow variances from one or more of the requirements of this Section provided that (1) the watershed control of the area is improved, and (2) complete backfilling with spoil material covers completely the highwall (which material will maintain stability following mining and reclamation), and (3) the owner of the surface knowingly requests in writing as part of the permit application that such a variance be granted.
    (f) Variances under subsection (e) of this Section may be allowed only if the Department finds that:
    (1) after consultation with the appropriate land use planning agencies, if any, the potential use of the affected land constitutes an equal or better economic or public use than would occur without the variance;
    (2) the potential use is designed and certified by a qualified registered professional engineer in conformance with professional standards established to assure the stability, drainage, and configuration necessary for the intended use of the site; and
    (3) after approval of the Illinois Department of Transportation and the Illinois Environmental Protection Agency the watershed of the affected land is deemed to be improved.
    (g) If a variance is granted under this Section, only such amount of spoil may be placed off the mine bench as is necessary to (1) achieve the planned postmining land use, (2) insure stability of the spoil retained on the bench, and (3) meet all other requirements of this Act. All spoil placement off the mine bench must comply with Section 3.17.
    (h) The Department shall promulgate rules to govern the granting of variances in accord with the provisions of this Section, and may impose in such rules such additional requirements as it deems necessary to accomplish the purposes of this Act.
    (i) All variances under this Section shall be reviewed not more than 3 years from the date of issuance of the permit, unless the permittee affirmatively demonstrates that the proposed development is proceeding in accordance with the terms of the reclamation plan.
(Source: P.A. 81-1509.)