Prism project: A proposal for the UK's problem plutonium

Of all the issues facing the UK’s nuclear sector, the problem of plutonium is perhaps the trickiest. But a solution that could feed into a perceived need for the country to resume a position of developing and building new reactor technologies in the future is currently before the Nuclear Decommissioning Authority.

The UK has a lot of plutonium — the largest civil stockpile in the world, totalling some 112 tonnes, most of it from reprocessing spent fuel over the years. The question of what to do with Britain’s plutonium has vexed subsequent governments for decades. Should it be treated as waste and kept in storage until its radioactivity has transformed it into something less hazardous? Or, seeing as it is a fissile material, should it be treated as a fuel for future nuclear reactors? This has recently emerged as a favoured option, with the plutonium to be converted into a mixed metal oxide (MOX) fuel at an unspecified date; this fuel could be used to fuel conventional reactors, such as those planned for the UK’s new nuclear build. This would convert it into a spent fuel that would still need storage, but it would no longer pose a weapons risk.