SKB signs collaboration agreement for the Spent Fuel Repository
Swedish Nuclear Fuel and Waste Management Co. (SKB) has signed a collaboration agreement with Implenia for the construction of the Spent Fuel Repository’s hard rock facility in Forsmark. The assignment includes the planning, design and construction of access routes down to a repository level of 500 metres and the first parts of the final repository.

Stefan Engdahl CEO
Photo Mikael Wallerstedt
The Spent Fuel Repository is SKB’s largest construction project, and it is in this facility that spent nuclear fuel from the Swedish nuclear power plants will be disposed of. The repository will be built in Forsmark in Östhammar municipality, and preparatory work above ground began officially at the beginning of the year. A collaborative partner has now been selected to work with SKB to build the underground repository facility.
The agreement covers an access tunnel, three vertical shafts for ventilation and a lift, a central area and main tunnels and transport tunnels to the first repository areas, where the spent nuclear fuel is to be disposed of. Rock construction work will take just over eight years and is a project worth several billion Swedish kronor.
– The construction of the Spent Fuel Repository is an important step in our mission to dispose of the radioactive waste safely. We are happy to have signed a collaboration agreement with Implenia, as they possess solid expertise and experience in rock excavation and infrastructure projects, says Stefan Engdahl, CEO of SKB.

The agreement covers an access tunnel, three vertical shafts for ventilation and a lift, a central area and main tunnels and transport tunnels to the first repository areas.
Preparations for rock excavation to start immediately
This autumn, Implenia will establish outbuildings, workshops and other necessary infrastructure in Forsmark. But before rock excavation work can commence, approval is required from the Swedish Radiation Safety Authority, which is currently reviewing SKB’s safety analysis report.
– We’re very proud to have been awarded this contract. Being selected for the planning, design and construction of this facility together with SKB offers strong proof that our strategy is a timely one. We look forward to a successful collaboration with SKB, one in which we can contribute our ability to collaborate, our working methods and our technical expertise, says Jiri T. Englén, CEO of Implenia Sweden.
The extension of the Spent Fuel Repository will take place in several stages before disposal can commence during the 2030s. The extension will continue for several decades, and the repository will be fully extended at some time in the 2080s
- The final repository will be located at a depth of around 500 metres in rock that is 1.9 billion years old.
- It is planned to hold approximately 12,000 tonnes of spent nuclear fuel in 6,000 canisters.
- The surface section will cover a total area of 24 hectares, the equivalent of 44 football pitches.
- When fully extended, the repository will contain more than sixty kilometres of tunnels. The underground space required for this is approximately four square kilometres.
- When the Spent Fuel Repository is fully extended, the volume of rock excavated would fill approximately 4.5 Avicii Arenas (Globe). This corresponds to around 2.7 million cubic metres.
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