There are two main strategies for decommissioning: immediate dismantling or deferred dismantling after safe enclosure. The German Atomic Energy Act (AtG) originally considered both strategies as equivalent. However, the Act on the Reorganisation of Responsibility in Nuclear Waste Management amended Section 7, paragraph 3 of the Atomic Energy Act: safe enclosure may now be chosen solely on a case-by-case basis for reasons of radiation protection.
The common feature of the two strategies is that between permanent shutdown and the start of decommissioning, there is the post-operational phase, which may last several years. During this period, the fuel assemblies may be removed, or the operational media and waste disposed of, insofar as this is covered by the operating licence for the nuclear power plant. During the post-operational phase, at the latest, the operator of the facility applies for the decommissioning licence. Decommissioning and dismantling activities may commence only when this licence has been granted.