Filed for The Guardian, 19 August 1993
An accident in a nuclear submarine could cause radioactive contamination in breach of safety limits more than 100 kilometres away, according to confidential naval training documents.
This is far more widespread than previously admitted and puts millions of people throughout Britain at risk. Nuclear-powered submarines are based at Plymouth, on the Clyde near Glasgow and at Rosyth near Edinburgh, as well as having berths at Southampton, Portsmouth, Torbay, Cardiff, Liverpool, Skye and the Shetlands.
In a report prepared by the Royal Naval College in Greenwich for a training course on nuclear accidents a “worst case” scenario is suggested which would cause radiation in excess of the emergency action levels to spread “beyond 100 km.” It says that “the entire contents of a reactor compartment could be released in a very short time (minutes).”
This contrasts with statements made on Wednesday by naval officials launching a nuclear emergency pamphlet for 30,000 households close to the Devonport submarine yard in Plymouth. They assumed that contamination would not spread more than two kilometres and that an accident “will take quite some time to develop.”
The Ministry of Defence has previously told local authority emergency planners that people up to ten kilometres from an accident could be affected. But the probability of such as accident is said to be about once in every million years of reactor operation.
The MoD said yesterday that the scenario in the training documents, which are all marked “restricted”, was “a theoretical accident which is virtually inconceivable.” Its probability was so small as to defy precise calculation.
The documents were revealed by the Scotsman newspaper yesterday a few hours before the Defence Secretary, Malcolm Rifkind, officially opened a £1.7 billion plant for Trident nuclear submarines at Faslane on the Clyde. They come in the wake of yesterday’s reports of a collision between a French nuclear submarine and an oil supertanker off the Riveria coast.
“These documents will increase public awareness of the serious dangers inherent in having naval nuclear reactors berthing in some of the UK’s most densely populated areas,” said Greenpeace consultant William Peden.
Another of the secret Royal Naval College reports provides a graphic account of the dangers of a nuclear weapons accident. A dangerous cloud of radioactivity could be created by the explosion of the conventional high explosives in the warhead, spreading deadly particles of plutonium and other highly toxic materials.
Beryllium, a toxic metal used to enhance the nuclear explosion, is said to cause an incurable disease producing ulcers, shortness of breath, chronic coughing, loss of weight and extreme nervousness between three months and 5 years after exposure. It can kill within a year or render people progressively disabled over years.
The decontamination of people poisoned by beryllium should be “just as thorough” as that for plutonium, says the report. It also describes the tritium used in H-bombs as a “severe biological hazard” and warns that it could “diffuse through” protective clothing after two or three hours.