1. Every operator to whom a permit is issued pursuant to the provisions of sections 444.760 to 444.790 may engage in surface mining upon the lands described in the permit upon the performance of and subject to the following requirements with respect to such lands:
(1) All ridges and peaks of overburden created by surface mining, except areas meeting the qualifications of subdivision (4) of this subsection, or where washing, cleaning or retaining ponds and reservoirs may be formed under subdivision (2) of this subsection, shall be graded to a rolling topography traversable by farm machinery, but such slopes need not be reduced to less than the original grade of that area prior to mining, and the slope of the ridge of overburden resulting from a box cut need not be reduced to less than twenty-five degrees from horizontal whenever the same cannot be practically incorporated into the land reclaimed for wildlife purposes pursuant to subdivision (4) of this subsection. In surface mining the operator shall remove all debris and materials not allowed by the reclamation plan before the bond or any portion thereof may be released;
(2) As a means of controlling damaging erosion, the director may require the operator to construct terraces or use such other measures and techniques as are necessary to control soil erosion and siltation on reclaimed land. Such erosion control measures and techniques may also be required on overburden stockpiles if the erosion is causing environmental damage outside the permit area. In determining the grading requirements to restore barite pit areas, the sidewalls of the excavation shall be graded to a point where it blends with the surrounding countryside, but in no case should the contour be such that erosion and siltation be increased;
(3) In the surface mining of tar sands, the operator shall recover and collect all spent sands and other refuse yielded from the processing of tar sands, whether such spent sands and refuse are produced at the surface mine or elsewhere, in the manner prescribed by the commission as conditions of the permit, and shall finally dispose of such spent sands and refuse in the manner prescribed by the commission as conditions of the permit and in accordance with the provisions of sections 444.760 to 444.790 ;
(4) Up to and including twenty-five percent of the total acreage to be reclaimed each year need not be graded to a rolling topography if the land is reclaimed for wildlife purposes as required by the commission, except that all peaks and ridges shall be leveled off to a minimum width of thirty feet or one-half the diameter of the base of the pile at the original ground surface whichever is less;
(5) Surface mining operations that remove and do not replace the lateral support shall not, unless mutually agreed upon by the operator and the adjacent property owner, remove the lateral support in the vicinity of any established right-of-way line of any public road, street or highway closer than a distance equal to twenty-five feet plus one and one-half times the depth of the unconsolidated material from such right-of-way line to the beginning of the excavation; except that, unless granted a variance by the commission, the minimum distance is fifty feet. The provisions of this subdivision shall apply to all existing surface mining operations beginning August 28, 1990, except as provided in subsection 3 of section 444.770 ;
(6) If surface mining is or has been conducted up to the minimum distance as defined in subdivision (5) of this subsection along an established right-of-way line of any public road, street or highway, a barrier or berm of adequate height shall be placed or constructed along the perimeter of the excavation. Adequate height shall mean a height of no less than three feet. Such barriers or berms shall not be required if barriers, berms or guardrails already exist on the adjoining right-of-way. Barriers or berms of adequate height may also be required by the commission when surface mining is or has been conducted up to the minimum distance as defined in subdivision (5) of this subsection along other property lines, but only as necessary to mitigate serious and obvious threats to public safety;
(7) The operator may construct earth dams to form lakes in pits resulting from the final cut in a mining area; except that, the formation of the lakes shall not interfere with underground or other mining operations or damage adjoining property and shall comply with the requirements of subdivision (8) of this subsection;
(8) The operator shall cover the exposed face of a mineral seam where acid-forming materials are present to a depth of not less than two feet with earth that will support plant life or with a permanent water impoundment, terraced or otherwise so constructed as to prevent a constant inflow of water from any stream and to prevent surface water from flowing into such impoundment in such amounts as will cause runoff or spillage from said impoundment in a volume which will cause kills of fish or animals downstream. The operator shall cover an exposed deposit of tar sands, including an exposed face thereof, to a depth of not less than two feet with earth that will support plant life, and in addition may cover such deposit or face with a permanent water impoundment as provided above; however, no water impoundment shall be so constructed as to allow a permanent layer of oil or other hydrocarbon to collect on the surface of such impoundment in an amount which will adversely affect fish, wildfowl and other wildlife in or upon such impoundment;
(9) The operator shall reclaim all affected lands except as otherwise provided in sections 444.760 to 444.790 . The operator shall determine on company-owned land, and with the landowners on leased land for leases that are entered into after August 28, 1990, which parts of the affected land shall be reclaimed for forest, pasture, crop, horticultural, homesite, recreational, industrial or other use including food, shelter, and ground cover for wildlife;
(10) The operator, with the approval of the commission, shall sow, set out or plant upon the affected land, seeds, plants, cuttings of trees, shrubs, grasses or legumes. The plantings or seedings shall be appropriate to the type of reclamation designated by the operator on company-owned land and with the owner on leased land for leases entered into after August 28, 1990, and shall be based upon sound agronomic and forestry principles;
(11) Surface mining operations conducted in the flood plains of streams and rivers, and subject to periodic flooding, may be exempt from the grading requirements contained in this section if it can be demonstrated to the commission that such operations will be unsafe to pursue or ineffective in achieving reclamation required in this section because of the periodic flooding;
(12) Such other requirements as the commission may prescribe by rule or regulation to conform with the purposes and requirements of sections 444.760 to 444.790 .
2. An operator shall commence the reclamation of the area of land affected by its operation as soon as possible after the completion of surface mining of viable mineral reserves in any portion of the permit area in accordance with the plan of reclamation required by subsection 9 of section 444.772 , the rules and regulations of the commission, and the conditions of the permit. Grading shall be completed within twelve months after mining of viable mineral reserves is complete in that portion of the permit area based on the operator's prior mining practices at that site. Mining shall not be deemed complete if the operator can provide credible evidence to the director that viable mineral reserves are present. The seeding and planting of supporting vegetation, as provided in the reclamation plan, shall be completed within twenty-four months after with mining has been completed survival of such supporting vegetation by the second growing season.
3. With the approval of the director, the operator may substitute for all or any part of the affected land to be reclaimed an equal number of acres of land previously mined and not reclaimed. If any area is so substituted the operator shall submit a map and reclamation plan of the substituted area, and this map and reclamation plan shall conform to all requirements with respect to other maps and reclamation plan required by section 444.772 . The operator shall be relieved of all obligations pursuant to sections 444.760 to 444.790 with respect to the land for which substitution has been permitted. On leased land, the landowner shall grant written approval to the operator for substitutions made pursuant to this subsection.
4. The operator shall file a report with the commission within sixty days after the date of expiration of a permit stating the exact number of acres of land affected by the operation, the extent of the reclamation already accomplished, and such other information as may be required by the commission.
5. The operator shall ensure that all affected land where vegetation is to be reestablished is covered with enough topsoil or other approved material in order to provide a proper rooting medium. No topsoil or other approved material is required to be placed on areas described in subdivision (4) of subsection 1 of this section or on any areas to be reclaimed for industrial uses as specified in the reclamation plan.
6. The commission may grant such additional time for meeting with the completion dates required by sections 444.760 to 444.790 as are necessary due to an act of God, war, strike, riot, catastrophe, or other good cause shown.