Three masts sticking up above the waves near the coastal town of Sheerness in the UK mark the spot where a deadly wreck has been rusting for almost 80 years. They belong to the SS Richard Montgomery, a US second world war-era ship that ran aground in August 1944 with a cargo of bombs. The half-submerged wreck, just 2 kilometres from land, still has 1400 tonnes of TNT in its holds.
Almost 20 years after I mounted an investigation for New Scientist into the dangers posed by this doomsday wreck, the UK government has now announced plans to cut back the thick steel masts this year to reduce their weight. This is to prevent them collapsing into the holds, where they would fall onto the bombs and set off an explosion.
A spokesperson for the Department for Transport says the wreck “is in a relatively stable condition” and added that “expert wreck assessors are now undertaking detailed surveys” to determine how much to shave off the masts.
When I began our investigation in 2004, I wanted to find out the dangers posed by this wreck. What were the chances of an explosion? And how serious would it be? The answers were far from reassuring.
A large part of the cargo was removed in 1944. But work stopped after the Admiralty – the UK government department responsible at the time – refused to pay workers danger money for unloading the bombs. This was the best chance the government would ever have to make the ship safe. Sixty years later, the wreck was disintegrating and the explosives were unstable.
Our investigation revealed that the government’s Explosives Research and Development Establishment (ERDE) had calculated in 1972 that the blast from an explosion at the wreck would shatter virtually every window in Sheerness and send a 300-metre-wide column of mud, metal and munitions shooting up almost 3 kilometres into the air. As part of the investigation, New Scientist asked researchers at Defence Research and Development Canada to check these alarming calculations and they confirmed the results.
A blast on this scale would be one of the world’s biggest non-nuclear explosions, causing widespread destruction and death. The proximity of a giant liquefied natural gas terminal at the Isle of Grain is an additional worry. Supertankers on their way to the terminal pass as close as 200 metres to the wreck.
So how likely is an explosion? Unexploded bombs are always dangerous and unpredictable, which is why they are normally made safe as soon as they are found. A particular problem with the SS Richard Montgomery is that many of the smaller fragmentation bombs were fused, ready for use; bombs would normally be transported without fuses for safety.
“Some of these fused bombs may, in all probability, go through a period of enhanced sensitivity,” said the ERDE in 1972. In 1999, the UK government asked consultants to carry out a risk assessment. They concluded that “some [bombs] may not have passed their most sensitive phase, and have a higher risk of premature detonation”. The consultants said the wreck would start to collapse in 10 to 20 years and the explosion of one bomb could start a chain reaction. Doing nothing was no longer an option, they said. In 2001, senior officials met to discuss this report and agreed the time for procrastination was over. That was 21 years ago.
This week I spoke to David Alexander at the Institute for Risk and Disaster Reduction at University College London, who has taken a keen interest in the SS Richard Montgomery. He says the bombs need to be removed. “Sooner or later they have to do something,” says Alexander. “The question is will they do it too late.”
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