The following performance standards shall be applicable to steep slope surface coal mining and shall be in addition to those general performance standards required by this act. These provisions shall not apply to those situations in which an operator is mining on flat or gently rolling terrain, on which an occasional steep slope is encountered through which the mining operation is to proceed, leaving a plain or predominantly flat area.
1. The operator shall insure that when performing surface coal mining on steep slopes, no debris, abandoned or disabled equipment, spoil material, or waste mineral matter be placed on the downslope below the bench or mining cut;2. 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;3. The operator may not disturb land above the top of the highwall unless the Department finds that such disturbance will facilitate compliance with the environmental protection standards of this act. The land disturbed above the highwall shall be limited to that amount necessary to facilitate said compliance; and4. For the purposes of this section, the term steep slope is any slope above twenty (20) degrees or such lesser slope as may be defined by the Department after consideration of soil, climate and other characteristics of a region or state.Okla. Stat. tit. 45, § 755
Laws 1978, c. 10, § 15, emerg. eff. 2/2/1978.