The Swiss authorities want to build the nuclear waste repository in the north of the cantons of Zurich and Aargau and in the immediate vicinity of the German border. The most important answers.
The Stadel gravel plant in Windlach in the municipality of Stadel. A facility for the nuclear repository could be built near here.
The most important thing from the press conference
- The National Cooperative for the Disposal of Radioactive Waste (Nagra) established in a press conference since 9 a.m. their decision for the Nördlich Lägern region in the cantons of Zurich and Aargau. The most pressing questions: Why was the location discarded in 2015? Why did Nagra choose him after all?
- Roman Mayer, Deputy Director of the Swiss Federal Office of Energy, emphasizes that Nagra is only announcing today which location is the most suitable from “their point of view”. It is not yet about the location, which has finally been checked and approved by the authorities. Nagra “only” announces the location for which it wants to draw up a permit application. It is a step of transparency and the prerequisite for being able to discuss the project with the cantons. Only when the application has been submitted can the federal government start examining the application in two years. The Federal Council could probably decide on the application in 2029. Then Parliament would also have to decide, and this decision would be subject to a referendum. The construction of the repository is not expected until 2045.
- Matthias Braun, CEO of Nagra, says: “Nörd Lägern is the best location.” It was a clear decision. To justify the decision, Braun shows the journalists present a piece of Opalinus Clay rock: 175 million years old. The rock is very dense and binds radioactive materials like a magnet. “If it breaks, it heals by itself.” There is a thick layer of this rock, which is ideal for storage, in every region. It is the most important geological barrier. Traces of ancient water were found in the layers of the Opalinus Clay. Above and below the Opalinus Clay layers, aquifers are important for the containment of radioactive material. Nördlich Lägern offers the largest area in which the Opalinus Clay is stored calmly and undisturbed and is protected from erosion.
- Braun explains why Nördlich Lägern is now the best location, even though Nagra wanted to drop the region from the selection process in 2015. At that time there were structural and technical uncertainties. However, the subsequent investigations revealed that the decision was “too cautious”. Because the cantons objected to Nagra, Nördlich Lägern was examined again, just like the other two sites, says Braun. The exclusion criteria were not convincing. Nagra then found out “with a much better data situation” that the construction and operation of a deep repository would work in all three regions. However, it turned out that Nördlich Lägern was the best location. For the Zurich government councilor Martin Neukom, this shows that criticism has made the project better, he said at the press conference.
- In addition to building below, building on the surface must also be carefully planned and constructed. The entrance to the repository is to be built in the Haberstal area in the municipality of Stadel. The packaging systems are planned for the interim storage facility in Würenlingen. The existing facility is to be expanded there. Resources would be saved there and synergies used in an existing industrial area. According to Braun, Nagra is expected to submit a general license application in 2024.
- Felix Altorfer, Head of Waste Management at the Ensi Nuclear Inspectorate, explains the next steps. The report justifying the choice of site will be examined first. Ensi experts and international experts are involved in this. In addition, the expert group “Deep Geological Repository” – as in the entire process – comes into play. It was made up of eight professors, four Swiss and four Germans, who would independently review the site selection report on a scientific and technical basis. Braun emphasizes that there are still points that could stop the project. As soon as certain suitability criteria can no longer be met, the work would be stopped according to international practice.
- Altorfer is also trying to allay concerns about the radiation from the radioactive waste. The safety analyzes would have shown reassuring values here. The Opalinus Clay rock in Nördlich Lägern is so good that the affected population at the repository only gets a dose of one hundred thousandth of a millisievert per year. That is significantly less than natural radiation. The average exposure of the population here is six millisieverts.
- According to Zurich government councilor Martin Neukom, the decision was not made politically because the resistance of the population in Nördlich Lägern was lower than in Weinland, for example. The Zurich government did not want to be the location for a nuclear repository. But safety has priority. And if it turns out that Nördlich Lägern is the safest location, then you have to accept that. There is no evidence that Nagra acted politically. The experts from the cantons also came to the conclusion that Nördlich Lägern was the best location. However, further decision-making will be monitored critically, according to Neukom.
- The final storage will cost around CHF 20 billion. The different costs at the sites did not play a role in the decision, says Braun from Nagra.
- Present at the press conference were: Roman MayerDeputy Director Federal Office of Energy, Matthew BrownCEO of Nagra, Monika Stauffer, Head of the Radioactive Waste Section, Swiss Federal Office of Energy, Felix AltorferHead of Waste Management Supervision Nuclear Inspectorate Ensi, Martin NeukomGovernment Councilor of the Canton of Zurich
The Nagra press conference live.
Where should the repository be located?
It has been clear since Saturday: Switzerland’s nuclear waste is to be stored in the depths of the Nördlich Lägern region in future. Access to the repository is to be in the Haberstal area in the municipality of Stadel (ZH). Another option was previously considered in the municipality of Weiach.
The Nördlich Lägern region is located north of the city of Zurich near the border with Germany and is 123 square kilometers in size. Twelve Zurich and three Aargau communities belong to it. Around 30 other communities in Germany are also affected by a possible repository. Around 52,000 people live in the region.
Why did Nagra choose Nördlich Lägern?
“The geology has spoken,” Nagra boss Matthias Braun told SRF on Saturday. Nagra found the largest safety reserves in Nördlich Lägern. It is a “clear geological decision”. Nevertheless, some question marks remain: In 2015, the region was temporarily removed from the list of favorite locations.
But now it seems to have found the best geological conditions there. Dense layers of rock are the most important element for a deep repository. In the end, there were three locations to choose from: All of them have a more than hundred meter thick, very dense and calm Opalinus Clay layer underground. The Opalinus Clay is considered to be the most important safety barrier that contains the radioactive waste in the long term.
It is to be expected that Nagra will declare these properties in the Nördlich Lägern area to be decisive and will therefore only give scientific and not political reasons for the decision. Because it is also speculated that the low resistance in the region could have played a role.
Nuclear waste is currently stored in the interim storage facility in Würenlingen in the canton of Aargau. This is near the Nördlich Lägern region. The interim storage facility in Würenlingen is to be expanded as a fuel element packaging facility.
According to which criteria was the decision made?
In the last three years alone, Nagra has spent CHF 240 million on drilling at the three sites that were most recently considered. The decision was made based on 13 safety criteria.
These are strictly scientific criteria. The proximity of the location to a nuclear power plant or the extent of the resistance of the population in the region were not relevant for the decision.
How big would the camp be?
It is already clear that Nagra wants to build two storage facilities – one for low-level and intermediate-level waste and one for high-level waste. From the geologists’ point of view, such a so-called “combined storage facility” has ecological advantages and is also significantly cheaper than two separate individual storage facilities at different locations.
The dimensions of the repository are correspondingly large: the caverns and tunnels, in which the radioactive material is to be locked up, are to extend over an area of no less than four square kilometers.
The low- and medium-level material is to be stored in final containers that are deposited in spacious caverns. The highly radioactive material, in turn, is to be stored in small tunnels in the middle of the Opalinus Clay layer. These are lined with bentonite, a rock that swells when it gets wet, thereby sealing cracks and crevices.
How will the canton of Zurich react to the decision?
The location decision can hardly be averted. After the canton of Nidwalden had been able to resist a repository on several occasions since the 1980s, the legislation was changed in such a way that the canton selected as the location could no longer resist. The government of the canton of Zurich has already announced that it will accept the decision.
How long will it take before a final decision is made?
It will probably take another ten years before a definitive decision is made as to where the repository will be located. In the next stage, Nagra will now prepare a general license application for the site, which will then be examined by various federal control bodies and other experts, including the nuclear supervisory authority (Ensi) and the Federal Office of Energy.
If the application is approved, the Federal Council and later Parliament will decide on the location, which should happen around 2030. The location decision is subject to an optional referendum. It cannot be ruled out that the electorate will ultimately overturn the decision. The search for a deep repository would then have to start all over again.
Which locations were discussed?
Two other locations were recently selected: the “Bözberg” area in Aargau and “Zürich Nordost” between Winterthur and Schaffhausen.
There are differences between the three areas. For example, the Opalinus Clay layer is not equally deep everywhere. The rock layers above and below the Opalinus Clay are also different. The risk of tectonic movements that could affect the storage of radioactive waste was also assessed.