Finland readies world's first underground storage for spent nuclear fuel

’ Preparations are underway to start the disposal of spent nuclear fuel in the Finnish bedrock next year, as the first place in the world to implement underground storage of high-level nuclear waste. The storage site is at Olkiluoto in Eurajoki, southwest Finland’

Onkalo, meaning “pit” or “cavity” in Finnish, will shelter spent uranium fuel nearly half a kilometer below Earth’s surface outside the town of Eurajoki. A series of barriers—giant copper casks, water-absorbing bentonite clay, and water-resistant crystalline rock—are expected to protect harmful radionuclides from seeping out of the site and into the local ecosystem. However, the decidedly nonporous rock still contain cracks, and Posiva—the nuclear waste company in charge of the project—had to map and avoid them as workers dug deeper.

The project is crucial to mitigating risk for Finland’s nuclear energy sector, which will account for 40% of the country’s electricity after a fifth reactor comes online this year. If successful, Onkalo’s copper casks will keep spent uranium safe and dry until it has decayed to acceptable levels—at least 100,000 years in the future.’


Finland has all 5 reactors operating since 2022.

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Sanity exists in the world? Oh, but it is Finland, so small and reliably sane as to almost not count…

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At least they demonstrate how it can be done when the political environment allows.


Is there any political environment in France, China, Russia, UK, or Canada that is holding them back from doing what Finland is doing? They are still thinking about what to do.

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