Finland will soon begin burying spent nuclear fuel in the world’s first ‘geological grave’, where it will be stored for 100,000 years. 

The groundbreaking project was hailed as a watershed moment for the long-term viability of nuclear power and a model for the entire world. Sometime either next year or early 2026, the highly radioactive spent nuclear fuel will be packed into sealed containers and deposited in rock, about 400 meters below the forests of southwestern Finland.

The durable copper vessels will be isolated, separated from humans, and preserved underground for hundreds of thousands of years.

“Onkalo,” which is the trademark of the long-term disposal facility, means pit in Finnish. It’s an apt name for the repository, which is located next to three nuclear reactors on the island of Olkiuloto, about 240 kilometers from the capital Helsinki.

Posiva was established in 1995 and is responsible for handling the final disposal of spent nuclear fuel rods at Onkalo. The Finnish company is jointly owned by the nuclear power company TVO and the utility Fortum.

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The Onkalo project involves an encapsulation unit and a spent fuel disposal facility and is forever, Pasi Tuohimaa, Posiva’s chief communications officer, told CNBC. It is the first of its kind geological storage facility for nuclear waste and has attracted great interest from the players of the nuclear energy industry, which, after the energy crisis in Europe, is in a recovery phase. 

Onkalo has sparked debate about whether one can guarantee the long-term safety of nuclear waste and the extent to which atomic energy should be used to combat the climate crisis.

Nuclear power currently provides about 9% of the world’s electricity, according to the World Nuclear Association. As it is extremely low-carbon, its proponents stress that it has the potential to play an important role in helping countries produce clean electricity, curb emissions, and reduce their reliance on fossil fuels.

Some environmental groups, however, say that the nuclear industry is an expensive and harmful way to distract from cheaper and safer alternatives.

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