If there is a cessation of mining or reclamation which is not set forth in either the mining plan or the reclamation plan, the operator shall so notify the department within 48 hours and shall commence stabilization of the mining site according to rules established by the department. If the department determines after hearing that stabilization of the mining site is inadequate to protect the environment, the department shall order the operator to commence additional measures to protect the environment, including, if the cessation is reasonably anticipated to extend for a protracted period of time, reclamation according to the reclamation plan or part of the reclamation plan. Usual and regular shutdown of operations on weekends, for maintenance or repair of equipment or facilities or for other customary reasons shall not constitute a cessation of mining.