4 Va. Admin. Code § 25-40-390
The operator shall use a mining method which will ensure ground, wall, bench and bank stability, including benching and sloping at the angle of repose as necessary.
§§ 45.1-161.3, 45.1-161.294 and 45.1-161.305 of the Code of Virginia.
Derived from VR480-05-1.2 § 3.1, eff. July 19, 1989; amended, Virginia Register Volume 14, Issue 17, eff. July 1, 1998.