Sweden commenced construction on a final storage facility for spent nuclear fuel at Forsmark, approximately 150 kilometers north of Stockholm, with construction beginning on January 15, 2023, according to Svenska Dagbladet. The facility represents a step in addressing the long-standing challenge of safely disposing of radioactive waste generated by the country's nuclear power plants.
The Forsmark repository is designed to securely house 12,000 tons of spent nuclear fuel in approximately 6,000 copper canisters. These five-meter-long, corrosion-resistant copper capsules will be placed in cast iron, surrounded by a five-centimeter-thick copper shell, and packaged in clay before being buried 500 meters underground. The waste will be stored in tunnels totaling 60 kilometers in length, excavated into an ancient rock substrate that is 1.9 billion years old.
The project, estimated to cost approximately 12 billion kronor ($1.08 billion), will be financed by the nuclear industry, as reported by The Economic Times. However, the facility will not receive its first waste delivery until the late 2030s, and it will not be sealed until around 2080, when the tunnels are scheduled to be backfilled and closed.
Environment Minister Romina Pourmokhtari attended the symbolic groundbreaking ceremony. "It is difficult to assess the importance, for Sweden and for the climate transition, of the fact that the construction of a final storage facility has begun," she said, according to Proto Thema. She added, "They said it wouldn't work, but it works."
Despite the progress, safety concerns persist. The Swedish non-governmental organization MKG, which deals with nuclear waste, filed an appeal in a Swedish court seeking further safety checks regarding the Forsmark facility. MKG raised concerns based on research from the Royal Institute of Technology (KTH) in Sweden, which indicated that the copper capsules could corrode and leak radioactive elements into groundwater.
"We have room to wait ten years to make a decision, given that this is something that must be safe for 100,000 years," said Linda Birkendal, president of MKG, according to The Economic Times. The integrity of the copper canisters over such an extended period is critical to preventing environmental contamination.
The question of how to safely store deadly radioactive waste until it becomes harmless challenged the nuclear industry since commercial reactors began operating in the 1950s. The World Nuclear Association estimates that there are about 300,000 tons of spent nuclear fuel worldwide that require disposal. Most of the waste is currently stored in cooling ponds near the reactors where it was produced, a temporary solution that underscores the necessity for permanent repositories like Forsmark.
Finland is the only other country close to completing a permanent nuclear waste storage facility, having decided in 2015 to build a deep geological repository using the Swedish method. The Forsmark facility, however, will not have the capacity to store fuel from future reactors that Sweden plans to build.
Anticipating a transition from fossil fuels, many countries in Europe and around the world plan to construct new reactors to provide electricity, including Sweden, which aims to build another ten nuclear reactors by 2045. "We have a safe method. However, there is currently no plan for what new types of facilities will be built," said Anna Porelius, communications manager at Swedish Nuclear Fuel and Waste Management Company (SKB), according to SVT Nyheter.
Currently, about 8,000 tons of used nuclear fuel are stored in a central interim storage facility in Oskarshamn, which annually receives over 300 tons of nuclear fuel. The interim solution underscores the need for a permanent repository. The nuclear power industry estimates that the Forsmark facility's design aims to provide protection for 100,000 years, with the repository engineered to withstand geological changes, climate-related disasters, and future ice ages.
The construction of the Forsmark repository is a milestone in Sweden's efforts to manage nuclear waste responsibly. According to ETC, the project's design involves multiple protective barriers: copper canisters, bentonite clay, and the Swedish bedrock. Despite approvals from the Swedish Radiation Safety Authority and the Land and Environment Court, disagreements among researchers persist regarding the long-term strength of the copper capsules used for storage.
This article was written in collaboration with generative AI company Alchemiq