In surface coal mining:
1. Which is carried out at the same location over a substantial period of time when the operation transects the coal deposit;
2. The thickness of the coal deposits relative to the volume of the overburden is large; and
3. Where the operator demonstrates that the overburden and other spoil and waste materials at a particular point in the permit area or otherwise available from the entire permit area is insufficient, giving due consideration to volumetric expansion, to restore the approximate original contour;
the operator, at a minimum, shall backfill, grade and compact, where advisable, using all available overburden and other spoil and waste materials to attain the lowest practicable grade but not more than the angle of repose. The operator shall provide adequate drainage and cover all acid-forming and other toxic materials, in order to achieve an ecologically sound land use compatible with the surrounding region.
Laws 1978, c. 10, § 8, emerg. eff. Feb. 2, 1978.