Yahoo News UK carried a story today from French news agency Agence France-Presse:
EDF Energy, the British unit of French giant EDF, said on Monday it had decided to shut down four nuclear reactors at two plants in northern England as a precaution.
EDF Energy said it was shutting down two reactors at each of the Heysham and Hartlepool nuclear plants for at least about eight weeks.
It follows a defect at one of the four reactors, which has kept it out of action since June. The decision to shut down an additional three reactors was described as a “conservative decision” in a statement issued by EDF Energy.
EDF said the decision came after a boiler problem at the Heysham nuclear facility:
EDF Energy meanwhile said in a statement on Monday that its Heysham 1 Reactor 1 “remains shut down while work continues to characterise the nature of the defect” detected earlier this year.
“Although routine inspections of other boiler spines have not previously indicated any similar defects, EDF Energy has taken the conservative decision to shut down Heysham 1 Reactor 2 and Hartlepool Reactors 1 and 2 that are of similar design,” it said.
“Until the results of the further inspections are known it is not possible to advise exact return to service dates for these four reactors, however, an initial estimate is that these investigations will take around eight weeks,” the statement added.
The affected reactors are known as AGRs — advanced gas-cooled reactors, a design only used in England and Scotland. using graphite as the moderator in the reactor core and using carbon dioxide for cooling. There are a total of fourteen AGRs in current use, all built during the 1970’s and 1980’s, and all scheduled for closure within the next decade, although applications to extend the lives of the reactors are in various stages of scrutiny.