What should we do with Plutonium?

The special edition journal, co-edited by scientists from Cambridge University and the European Commission, will offer a range of strategies for Europe's expanding plutonium reserves in the wake of recent assertions that the UK stockpile should be used as fuel.

Plutonium stocks are already a source of mounting concern to the scientific community. Plutonium is highly toxic, especially if inhaled, and can in some forms be used to make nuclear bombs.

Earlier this year the Royal Society released its first report on the matter in a decade, urging the government to have the plutonium turned into fuel for power stations. At the moment, only Sizewell B would have the capacity to burn this type of fuel, but that could change if the government's wish to create a new generation of nuclear reactors is realised.

The new collection of reports, however, shows that turning plutonium into fuel is not the only option left for countries harbouring large quantities of the radioactive substance. For the first time, the special edition of Progress In Nuclear Energy brings together the views of scientists who believe that it should be used to feed power stations, and of those with other ideas.

“Opinion is still divided on whether the plutonium we have is a problem or an asset,” Dr Bill Nuttall, Senior Lecturer in Technology Policy at Judge Business School, University of Cambridge, who co-edited the publication, said.

“Our publication explores a range of options ranging from fuels for today's nuclear power plants and fuel for future reactor designs, right through to the possibilities for prompt disposal.

“This journal compiles the views of scientists with different perspectives on the matter, and gives them the chance to put forward their suggestions.”

Various contributors are fully in support of the nuclear fuel options, the most immediately relevant for the UK would involve combining the plutonium with uranium to create a mixed oxide or “MOx” fuel. MOx pellets are likely to be compatible not only with the proposed nuclear power stations currently being debated by politicians, but also with future power stations still on the scientific drawing board, referred to as “Generation 4” reactors.

Current MOx production capacity for UK plutonium is, however, limited by commitments to process MOx from overseas customers at the Sellafield MOx plant up until 2023.

As the journal shows, however, there are additional ways of managing plutonium. Nuclear physicists might be able to transmute it into a less dangerous substance using a particle accelerator. It could also be converted into a glass or glass waste form to be buried underground or, if time pressure so dictated, made into MOx pellets, not for use as fuel but simply to be a safer form for storage before waste disposal.

“The purpose of this report has not been to resolve whether plutonium is a hazardous waste or an asset,” Dr Ian Farnan, from the Department of Earth Sciences at the University of Cambridge, said. “In fact, as editors we have taken a deliberate decision not to take a view.

“What that has enabled us to do, however, is talk to people of either opinion in an open-minded way. The Royal Society has declared its view that separated plutonium is a problem. This new collection of papers for the first time gives policy-makers a full list of options, which hopefully will allow them to make a well-informed decision about what happens next.”

“Options for the Long-Term Management of Separated Plutonium” – a special edition of Progress In Nuclear Energy, is published by Elsevier. The edition has been edited by Dr William Nuttall and Dr Ian Farnan (University of Cambridge) and Dr Rudy Konings and Dr David Hamilton (European Commission, Joint Research Centre, Institute for Tranuranium Elements). Copies can be provided upon request.