Where is radioactive waste stored in?
Spent fuel from a reactor is stored under water in a concrete and steel pool to cool and shield it for at least ten years after it is removed from the reactor. After this time, it has decayed sufficiently and heat production is low enough such that it can be removed from the water and decay in the air. It is still shielded to prevent exposing people near it and it is kept under lock and key at the power plant or storage facility to maintain control.