/ 27 December 2007

Reactors could burn weapons plutonium

A new generation of nuclear power plants could burn 100 tonnes of surplus weapons-grade plutonium as a good way of keeping it away from terrorists, according to scientists working for the European Union.

Most of Britain’s weapons-grade plutonium is held in bunkers at the Sellafield complex in Cumbria, behind three perimeters of razor wire patrolled 24 hours a day by armed guards in one of the most closely guarded compounds in Europe. The material comes from reprocessing spent fuel at Sellafield over the past 50 years.

The plutonium was used initially for bomb making, then for feeding a now-abandoned European nuclear fast breeder reactor programme. But it has sat around unused for years, becoming a huge political embarrassment as well as a potential target for extremists.

The status of plutonium has shifted from its initial description by the United Kingdom Atomic Energy Authority as ”100 times more valuable than gold” to the Royal Society’s report this September that described it as a stockpile of highly dangerous toxic material that constitutes a serious terrorist threat.

Whatever solution the United Kongdom government adopts, the stockpile will cost billions of pounds to process and make safe since the material is held in its most dangerous form as an oxide power. One particle of the powder in the lungs can be a death sentence.

The idea that Britain could burn off the plutonium has been suggested in a report by scientists for the European commission, which has become increasingly concerned that there is no policy to deal with the threat.

The European commission aims to put the options contained in the report — a series of papers from European and US scientists co-edited at Cambridge University — to the half-dozen European governments that have an interest in plutonium stockpiles, the vast bulk of which are at Sellafield. Britain’s share is in excess of 100 tonnes.

The findings are being published in a special edition of the magazine Progress In Nuclear Energy. ”Opinion is divided on whether the plutonium we have is a problem or an asset,” said Bill Nuttall, one of the editors, from Cambridge’s Judge Business School. ”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.”

The Royal Society report in September proposed that the government burn as much plutonium as possible in the form of mixed plutonium and uranium fuel (MOX) in the Sizewell B pressurised water reactor in Suffolk, the only UK station able to use the fuel. Even this would only reduce the stockpile, not eliminate it, so the Royal Society suggested surplus MOX fuel — safer than pure plutonium — could simply be classified as waste and disposed of.

The problem with this policy is that Britain’s MOX plant at Sellafield does not work properly and all of its limited output is contracted to foreign power companies. The government would have to build a new MOX plant to use British plutonium and persuade a sceptical privatised nuclear industry to burn it. In any event, MOX fuel is much more expensive to produce and potentially more dangerous than uranium fuel and so would require heavy government subsidy.

One of the other suggestions that is already technically feasible would involve mixing the plutonium in glass or ceramics. This would allow storing or burying blocks of material in a form where the plutonium would not cause a spontaneous meltdown, which has to be constantly guarded against at Sellafield.

Other suggestions involve mixing the plutonium with thorium to use as fuel in a new generation of reactors — so removing the danger while producing electricity — and using a particle accelerator to destroy the plutonium, but neither process is yet a proven technology and, although there are no costings in the report, could be expensive.

Nuttall said: ”The Royal Society was clearly very concerned about the dangers of having so much untreated plutonium at Sellafield but came up with a narrow range of options. We have produced nine papers with a series of solutions so governments across Europe have a range of options without recommending any particular one.” – Guardian Unlimited Â