Editing Open-pit mining (section)

== After closure ==
Open-pit mines are typically worked until either the [[mineral resource classification|mineral resource]] is exhausted, or an increasing ratio of overburden to ore makes further mining uneconomic.{{cn|date=March 2024}} After open-pit mines are closed, they are sometimes converted to [[landfill]]s for disposal of solid waste. Some form of water control is usually required to keep the mine pit from becoming a lake. Several former open-pit mines have been deliberately converted into artificial lakes, forming areas such as the [[Lusatian Lake District]], the [[Central German Lake District]] or the Upper Palatinate Lake District. A particular concern in the formation of these lakes is [[acid mine drainage]].