Channel 4 News and the non-profit Nuclear Information Service have found new evidence of how last summer’s intense flooding halted operations for a full 9 months at one of Britain’s two nuclear weapons sites.
On 20 July 2007, the county of Berkshire was inundated by torrential rainfall. The Atomic Weapons Establishment’s Burghfield site, where warheads are serviced and disassembled, had some 84 buildings affected by the flooding—including some areas used for assembling nuclear components. Water and highly-enriched plutonium don’t mix—good ol’ H2O can make a pretty good neutron moderator, and could even lead to a nuclear chain reaction within a warhead. It wouldn’t be a full-scale blast in a properly maintained modern warhead, but it could still release radiation.
Fortunately, there was no chance of that happening. The flooding occurred on a weekend, while the Burghfield site was locked up tight, and emergency crews followed the correct protocol. Still, the damage was so extensive that nuclear work at Burghfield couldn’t begin again until the spring of 2009.
The UK’s other main nuclear site at Aldermaston, where atomic research is done, was unaffected by the flooding.
The full report on the incident is here, and a nice summary by the NIS is here.