When complete, facility will have more than 60 km of tunnels
Sweden’s nuclear fuel management company SKB has signed an agreement with Switzerland-based construction company Implenia for work on a deep geologic repository which will store highly radioactive spent nuclear fuel for 100,000 years.
SKB said the agreement includes planning, design and construction of accesses to a depth of 500 metres and the first areas of the repository.
The repository will house spent nuclear fuel from Sweden’s nuclear power plants at Ringhals, Forsmark and Oskarshamn.
Work began on the repository, at Forsmark in the municipality of Östhammar, in January. Construction is expected to take 10 years before deposition can begin, after which the facility will be gradually expanded.
SKB said Implenia will set up onsite infrastructure such as storage facilities this autumn. For excavation to begin, approval will be needed from the Swedish Radiation Safety Authority, which is reviewing SKB’s safety report.
The repository will be at a depth of approximately 500 meters in 1.9-billion-year-old rock. It will hold approximately 12,000 tonnes of spent nuclear fuel in 6,000 cannisters. When fully developed, it will have more than 60 km of tunnels.
In October, SKB received an environmental permit to build and operate the repository and a related encapsulation facility at Oskarshamn.
In January 2022, the Swedish government approved plans to build the repository and encapsulation facility.
SKB’s plan is for spent nuclear fuel to be encapsulated in copper and nodular cast iron at the encapsulation facility in Oskarshamn before being transported to the final repository close to the Forsmark nuclear power station, about 140 km north of Stockholm.
Sweden has six commercial reactors in operation at three nuclear stations: two at Ringhals, three at Forsmark and one at Oskarshamn. In January 2021, Ringhals-1 became the fourth commercial nuclear reactor to close in five years. The others were Ringhals-2, Oskarhamn-1 and Oskarhamn-2.
Prime minister Ulf Kristersson has said Sweden will begin construction on a new nuclear power plant before the country’s next legislative election in 2026 as it pushes ahead with ambitious plans to increase nuclear capacity.
