By 2010, enough plutonium will have accumulated at British Nuclear Fuel's (BNFL) Sellafield plant in Cumbria to make nearly 10,000 crude nuclear weapons, says the "scoping study" published yesterday by the Royal Society, the nation's premiere scientific society.
The stock of this highly toxic, radioactive metal is set to double over the next 10 years to 100 tons. "We're disturbed at the present lack of strategic direction for dealing with plutonium," said Sir Ron Mason, a former chief scientific advisor to the Ministry of Defence, who chaired the expert team. "What is the point of the British getting up in the United Nations and preaching the cause of nuclear non-proliferation world- wide when they are taking this risk at home?"
The plutonium in question is civilian, not military, and it comes from reprocessing the spent nuclear fuel from Britain's nuclear power stations. The plutonium in this spent fuel is mixed with other highly radioactive materials, including uranium, and is completely unsuitable for use in nuclear weapons.
But after reprocessing, the separated plutonium becomes a much more tempting target for any terrorist. Sir Ronald said only about 10kg - a briefcase full - would suffice to make a crude fission bomb.
The Royal Society study accepts that the growing quantities of plutonium at Sellafield are carefully stored and guarded. None the less, "the stockpile can be viewed as a strategic and environmental risk, as well as an open- ended legacy for future generations".
The two greatest nuclear powers, the United States and Russia have agreed that their surplus military plutonium should be converted into a form that is extremely difficult to turn into nuclear weapons. Britain's stockpile does not conform to that standard.
The Royal Society report says the British government and its state-owned nuclear power industry have no credible, long-term plans for reducing the plutonium or disposing of it in a completely safe manner. BNFL points out that it is merely storing the material on behalf of the companies which own Britain's nuclear power stations.
It could be buried in a dump deep underground in stable rock formations. But government and industry have spent more than pounds 400m trying to develop such a repository for intermediate level waste, only to have the idea scuppered last year by the then environment secretary, John Gummer.
BNFL has spent pounds 300m at Sellafield building a new plant which combines small quantities of plutonium with uranium to make a fuel for nuclear power stations. But there is only one British power station in which it could conceivably be burnt, Sizewell B on the Suffolk coast.
The study group urges the Government to carry out a comprehensive review using independent experts to find the best options for dealing with the mounting stockpile. Yesterday the environment minister Michael Meacher said the Government would be looking at the issues, but the plutonium was very safely stored. "This is something we have to deal with, but we're under no emergency pressure."