In Estonia there is a quota system – the government has set, for every county and the state as a whole, a maximum annual mining rate. In Europe this is quite unique and no other country boasts such a system.
The quota system is in force since summer 1996, yet actually it has not been met once. Even on summers with good weather only less than half of the quota has been mined.
According to the law the surface layer of earth that is left damaged due to mining must be restored.