Safe containment
The Secure inclusion is a concept of nuclear technology and relates to a variant of the Nuclear Decommissioning Authority .
concept
For safe containment, the area of the nuclear power plant that contains the essential radioactive components ( reactor pressure vessel (RPV), steam generator ) (usually the containment ) is transferred to a stable state after decommissioning : the fuel elements and all other radioactive media, coolants, Auxiliary materials, gases, etc. as well as all fire loads are removed. Then all radioactive components located outside the area (e.g. pumps, pipes, etc.) are transferred to this area and the building z. B. sealed by concrete inclusion.
The plant is left in this condition for a long time (usually several decades) until it is finally dismantled ; during this time only insignificant maintenance measures are necessary.
The aim of this measure is by a decay of radioactivity of nuclides with a low half-life to facilitate the future dismantling of the plant and to use necessary interim technical progress. The costs of the dismantling will only arise in the future. On the other hand, there are ongoing costs of the enclosed system and employees who are familiar with the system may no longer be able to contribute later with their experience.
The alternative to safe containment is direct dismantling without a decay phase. A Permanent safe enclosure (Engl. Entombment) is not a legal requirement in Germany.
practice
In Germany, safe enclosure has seldom been used as a decommissioning strategy. The decision as to which decommissioning strategy should be implemented is made by the plant operator as part of his corporate responsibility. However, the federal government gives preference to direct dismantling so as not to unnecessarily burden future generations.
Safe containment was applied for and approved by the operators for the THTR-300 thorium high-temperature reactor in Hamm-Uentrop and for the Lingen nuclear power plant . The approved containment period there ended in 2013 after 25 years. An overview of the current status of the decommissioning of nuclear facilities is published annually by the Federal Office for Radiation Protection .
This term got a special meaning in the attempt to contain the consequences of the Chernobyl accident : there two of the four reactor units were put into a multi-part concrete shell, which was given the name sarcophagus. The Chernobyl sarcophagus, however, is not a safe enclosure as a phase of the orderly decommissioning of a nuclear facility , but a (provisional) safety measure after an accident.
criticism
Nuclear opponents refer to the term safe enclosure as a euphemism . Due to the existing risks of damage to the shell or other release of radioactivity, the enclosure is not completely safe , cf. Damage to concrete structures .
Individual evidence
- ↑ a b BMUB: Decommissioning strategies in Germany ( Memento of the original from October 30, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. As of April 20, 2012
