Posiva is an Expert Organisation in Nuclear Waste Management

Posiva Oy is an expert organisation responsible for the final disposal of spent nuclear fuel of the owners.
Posiva has been established in 1995.

Why is copper a suitable material for final disposal canisters?

Copper endures the anoxic conditions deep inside the bedrock and will not corrode. There have been findings in the natural environment of metallic copper which is many millions of years old and it has retained good protective characteristics.

When will final disposal begin?

The final disposal of spent nuclear fuel is intended to begin in 2022.

What is the current location of the spent nuclear fuel?

At the moment, the spent nuclear fuel is stored in water basins in interim storage facilities at the Olkiluoto and Loviisa power plants. The water cools down the fuel assemblies and provides protection against radiation.

What will be the total amount of spent fuel?

According to existing plans, the Loviisa 1–2, Olkiluoto 1–2 and Olkiluoto 3 plant units will produce electricity for 50–60 years. Production results in about 5,500 tonnes of spent fuel. In addition, the operation of the planned Olkiluoto 4 unit for 60 years will increase the total amount of spent fuel up to 9,000 uranium tonnes.

How long will the final disposal of the spent fuel take?

The final disposal of spent fuel from the existing nuclear power plant units and the Olkiluoto 3 unit currently under construction will take about 100 years.

Have the effects of permafrost and a possible ice age been observed in planning the final disposal?

Yes. In the past, ice ages have been regular events and they are expected to also occur in the future. As a result, ice age conditions will be taken into account when planning the final disposal. Posiva carries out research in Greenland in permafrost conditions.


Posiva testing copper canister inspection technology at Olkiluoto

The copper cast iron canister is the most significant technical release barrier of the final disposal concept. It is required to remain intact for tens of thousands of years, which is why the quality of the canister must be fully verified prior to final disposal.

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21.03.2014 Posiva chose friction stir welding for the encapsulation of spent nuclear fuel

Copper - cast iron canister is the most important engineered barrier in the KBS-3 disposal concept for spent nuclear fuel adopted in Finland and Sweden. The copper canister consists of a copper tube with an integrated or a welded bottom and of a lid which is welded in the encapsulation plant after the spent fuel has been assembled into the canister. The properties of the weld shall not deviate from the properties of the copper components.

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Photos of ONKALO
Take a look at the image gallery and watch videos about final disposal and ONKALO.

What is final disposal about?
How will the final disposal of spent nuclear fuel be carried out in practise?

Posiva Core Question
Core Question Quiz
Play Posiva Core Question, the quiz and learn more on the safe management of spent fuel disposal.

Canister 1

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