Mühleberg nuclear power plant: This is how decommissioning works
The Mühleberg nuclear power plant will be taken off the grid from 2019. The operator BKW has informed about the timetable of the decommissioning.
In December 2019, the time will come: Switzerland's second-oldest nuclear power plant after Beznau I will be decommissioned. The operator BKW announced on April 4 that the first Decommissioning project Switzerland. The application, which BKW submitted to the Uvek last December, will now be made public. The project is to run for a total of 12 years, from the cessation of power operations to the official release of the site.
Three phases
If everything is accepted as planned by BKW, the decommissioning will proceed in three phases. After power operation is discontinued in 2019, dismantling will first be prepared by 2020: The fuel assemblies will be moved from the reactor to the storage pool, where they will initially decay for a few years. For this purpose, autonomous cooling of the storage pools will be set up. In addition, the movable plant parts and the components of the turbine building will be removed.
Removal of the fuel elements
The first part of the nuclear dismantling is scheduled for the years 2021 to 2024. The spent fuel assemblies will now be transported to the interim storage facility in Würenlingen and material handling will be set up. In addition, the core internals will be dismantled and decontamination of the buildings will begin. At the end of this second phase, there should be no fuel assemblies on the site. This means that over 98% of radioactivity will have been removed from the NPP. At the same time, the turbine building will be further cleared out and prepared as a treatment site for contaminated materials. For this purpose, enclosed work boxes with filtered exhaust air are being set up in it.
Phase three, complete nuclear dismantlement, is scheduled for completion by 2031. In this phase, all facilities will be dismantled, disassembled and decontaminated. If materials are still contaminated after treatment, they will be taken to the interim storage facility in Würenlingen and later finally stored in the planned deep geological repository.
Radiation-free in 2030
From 2030, there should be no more radioactive materials on the site. From then on, radiological measurements will ensure that the now former nuclear power plant no longer poses a radiological hazard. If this is the case, the authority can release the site for new uses.
From 2031, depending on the subsequent use of the site, conventional dismantling can begin. From 2034, the site should finally be free for new uses.
The entire process is expected to cost 2.1 billion Swiss francs, 800 million of which are earmarked for the decommissioning itself; the remaining 1.3 billion will be spent on safe disposal. To date, BKW has set aside just under 1.6 billion francs for the project.
Radioactive fraction below 2%
As BKW states, the amount of material that cannot be decontaminated and must be disposed of is about 3000 tons. The total mass of the NPP is 200,000 tons. Another 6% of the material is radioactively contaminated but can be decontaminated. The remaining 92% is normal construction waste that can be reused or else landfilled normally.
Partial reports on incidents, environment and safeguarding
In addition to the main report, the BKW application includes three sub-reports on the topics of incidents and environmental protection and safety. The former shows that any incidents that could occur in connection with decommissioning can be controlled thanks to the protective measures taken. The environmental impact report addresses the non-nuclear impacts of the decommissioning work on the environment. The Safeguards Report sets out the precautions that will be taken during decommissioning to protect the Mühleberg nuclear power plant from unauthorized interference from inside and outside the plant.
