Successive governments have kept the material to leave open the option to recycle it into new nuclear fuel
The UK government has announced plans to dispose of its 140 tonnes of radioactive plutonium, currently stored at the Sellafield nuclear facility in Cumbria. The stockpile, the largest in the world, has been accumulating for decades as a byproduct of nuclear fuel reprocessing.
For years, the plutonium has been stored in a form that allowed for the possibility of recycling it into new nuclear fuel. However, the government has now confirmed it will not pursue this option. Instead, it aims to render the material “beyond reach” by converting it into a stable form suitable for permanent disposal deep underground.
Decades of Accumulation
Plutonium is produced when spent nuclear fuel is separated into its components during reprocessing. Historically, successive governments kept this hazardous material to preserve the option of recycling it into fuel. However, this approach has proven to be costly and technically challenging.
Storing plutonium in its current form is not only expensive but also risky. The highly radioactive material must be repackaged frequently because the radiation damages its containers over time. Additionally, maintaining security at Sellafield requires armed police. Combined, these measures cost UK taxpayers more than £70 million annually.
A Safer and Economical Approach
In light of these challenges, the government has decided to “immobilise” the entire plutonium stockpile, which will involve converting the material into a stable, rock-like substance. This process will take place at a new facility to be constructed at Sellafield.
Energy Minister Michael Shanks emphasized the significance of the decision in a statement: “The objective is to put this material beyond reach, into a form which both reduces the long-term safety and security burden during storage and ensures it is suitable for disposal.”
Scientific Process for Disposal
Experts have explained that the plutonium will be transformed into a ceramic material, a process designed to ensure its long-term stability. Although the material will remain radioactive, the ceramic form is durable and suitable for deep geological disposal.
Dr. Lewis Blackburn, a nuclear materials scientist at the University of Sheffield, elaborated on the process: “The plutonium will be converted into a ceramic material, which is solid and stable, making it safe to dispose of. The exact type of ceramic is still being researched to identify the most suitable option.”
Prof. Claire Corkhill, a nuclear waste expert from the University of Bristol, described the government’s decision as a “positive step” toward addressing the risks associated with the stockpile. “This approach transforms the material and locks it into a solid, durable form that will last for millions of years in a geological disposal facility,” she said.
She added that the materials used for immobilisation are inspired by natural minerals known to have safely contained uranium for billions of years, providing confidence in their long-term effectiveness.
The Road to Geological Disposal
The government’s plan represents a significant shift in its approach to managing the country’s most hazardous radioactive waste. While the conversion of plutonium into a stable material is an important milestone, the ultimate goal is to dispose of it in a deep geological facility.
Such a facility, designed to house the UK’s most dangerous radioactive waste, is still in the early stages of development. The technical and political process of selecting a suitable site is expected to take years. The facility itself is not projected to become operational until at least 2050.
Moving Forward
The decision to immobilise the UK’s plutonium stockpile marks a turning point in the country’s nuclear waste management strategy. By opting for permanent disposal rather than recycling, the government aims to address both the economic and safety challenges posed by decades of plutonium storage.
While the path to establishing a geological disposal facility remains long, experts and officials agree that this step represents significant progress toward reducing the risks and costs associated with the UK’s hazardous nuclear materials.
