Md. Code, Environment § 15-614

An operator may not conduct deep mining within the State if he previously has forfeited any bond posted pursuant to deep mining activities, unless, on application, the operator repays to the Department the cost of reclamation, if the Department has reclaimed the land with interest at the current rate for the time elapsed, less the amount of the forfeited bond. If the land is still unreclaimed, the operator shall reclaim the land covered by the forfeited bond at his own expense, including any additional erosional, sedimentation, or pollution damage resulting from the lack of proper reclamation during the interim.