Briefs · Frontier Science
The nuclear waste repository in Finland designed to outlast modern civilisation
Finland has built a tomb for nuclear waste. It is meant to outlast civilisation itself.
Onkalo, carved into gneiss bedrock on the island of Olkiluoto, is the first engineered structure designed to last 100,000 years — ‘at least 100,000, if not a million’ (Allison Macfarlane, University of British Columbia). Spent fuel goes into copper canisters with walls 5 centimetres thick, lowered into holes in the bedrock under the Swedish KBS-3 system. In October 2026 the Finnish government granted the operating licence; the first waste shipments arrive in the coming months.
The caution is earned: Germany’s Asse II salt mine leaked after a few decades and now faces retrieval of some 47,000 cubic metres of waste. And warning people 100,000 years from now is its own puzzle — one abandoned idea was a landscape of giant thorns.
Conclusion: Onkalo is not a landfill. It is a time capsule nobody is meant to open.
Read the original at New Scientist
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