Sweden has taken a step in addressing one of the nuclear industry’s most persistent challenges—safely storing spent nuclear fuel for the next 100,000 years. The country has officially started building a final storage facility in Forsmark, approximately 150 kilometres north of Stockholm, becoming only the second nation after Finland to pursue such a long-term solution.
The question of how to securely store highly radioactive waste has haunted the nuclear industry since the first commercial reactors began operating in the 1950s. Today, there are an estimated 300,000 tons of spent nuclear fuel worldwide, with most of it currently stored in cooling ponds near reactors.
The Forsmark repository is designed to provide a permanent solution. This facility will comprise 60 kilometers of tunnels, located 500 meters deep in bedrock that is an astonishing 1.9 billion years old. The waste will be encased in five-meter-long, corrosion-resistant copper capsules, then sealed with protective clay and buried underground.
“This project is vital for Sweden and the global climate transition,” said Sweden’s Environment Minister, “They said it wouldn’t work, but it does.”
The Forsmark repository will house up to 12,000 tons of spent nuclear fuel generated by Sweden’s existing nuclear power plants. It is set to begin accepting waste in the late 2030s and is expected to be fully operational by 2080. After that, the tunnels will be permanently backfilled and sealed.
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(Image: SKB)
While the project is ambitious, it comes with a hefty price tag—approximately 12 billion Swedish crowns ($1.08 billion)—which will be fully funded by Sweden’s nuclear industry.
Despite the optimism, safety concerns remain. Reuters reported the Swedish NGO MKG has appealed for additional safety checks, citing research from the Royal Institute of Technology that suggests the copper capsules might corrode over time, potentially releasing radioactive elements into groundwater.
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“We need absolute certainty that this solution will remain safe for 100,000 years,” said Linda Birkedal, chair of MKG. “We can afford to wait ten years to ensure that every aspect of safety is thoroughly researched.”
This controversy highlightes the complexities of balancing technological innovation with environmental and safety concerns.
The Forsmark repository represents a critical step in Sweden’s broader energy strategy. While the facility will accommodate all waste from the country’s current nuclear reactors, it will not cover waste from future reactors. Sweden plans to construct 10 new reactors by 2045 to support its shift from fossil fuels.
Nuclear energy is seen as a key player in this transition, providing a reliable source of electricity with minimal greenhouse gas emissions. However, ensuring the long-term safety of radioactive waste storage remains a pressing global issue.