EDF Energy made a “conservative decision” to take both reactors at the Dungeness B nuclear power station in southern England offline for two months in May 2013 to further improve flooding defences, the company said today.
In a statement issued in response to a report in a national newspaper claiming that EDF Energy had “played down the threat” of flooding at the station, the company said the decision to take both reactors offline was to undertake additional protection to cover “extremely rare events” of the kind that might happen only one in 10,000 years.
Before this the site was deemed safe to operate and protected from events which would occur one in every 1,000 years by the Office of Nuclear Regulation, the statement said.
Part of the work included building a flood defence wall around the site which is due to be completed this month. Recent bad weather in the UK, including high tides and storms, has had no impact on operations at Dungeness B, the statement said.
The Independent newspaper today said one of the reactors had been “quietly taken offline” to allow work on a new flood protection wall, after EDF Energy alerted the Office of Nuclear Regulation that without urgent work the site was at risk of being “inundated” by sea water.
Quoting the ClickGreen website, The Independent said the closure of the reactor followed an internal EDF Energy report which found that the shingle bank sea defences were “not as robust as previously thought”, raising fears that they could be overwhelmed in extreme weather.
An EDF Energy spokesman said the closure was part of its “response to events in Japan which caused serious damage to Fukushima-Daiichi”. He said an extensive programme of analysis, modelling and physical testing has been carried out to review and update the assessments of potential flooding around EDF Energy’s nuclear sites.
ClickGreen said the news was not published by the company or the Department of Energy and Climate Change, but details were found buried in “obscure” files of the Health and Safety Executive.
Last month EDF Energy said it is planning to extend the operating life of the two Dungeness B reactors by 10 years until 2028.
Both units are advanced gas-cooled reactors. Dungeness B-1 began commercial operation in 1985 and Dungeness B-2 in 1989.
In 2013, EDF Energy and the UK government reached agreement on the principal commercial terms for an investment contract for a new nuclear power station at Hinkley Point C in southwest England. This is subject to state aid approval by the European Commission, which launched an investigation in December.