Safety assessment documents have come to light which report that major cracks have been located in some of the reactor cores of Britain's current generation of nuclear power stations. The documents were retrieved under the Freedom of Information Act, and show that the Nuclear Safety Directorate (NSD) had expressed concerns over the deterioration of reactor cores at Hinkley Point B in Somerset, among other U.K. nuclear power stations. The company, British Energy, which operates 13 advanced gas-cooled reactors (AGR) including Hinkley, apparently does not know fully why the cracking has occurred, is unable to monitor the progress of the deterioration and hence cannot provide a clear estimate of the extent of damage that has occurred.
Cracks in the graphite brick cores of the ageing AGR's have been noticed for some time, but without any real public awareness of the problem arising until now. In 2004 British Energy warned that it might not be possible to extend the lives of its Hinkley Point B, Hunterston B, Heysham 2 and Torness plants beyond the30 year span initially envisaged for them because of the cracked graphite brick problem. The company are keen to extend the lives of its AGR reactors but the papers, which were obtained by Greenpeace via "Stop Hinkley", a local nuclear watchdog group, suggest that unless British Energy introduces more stringent safety monitoring this might be impossible. The NSD says that it does not believe that there is any imminent public danger from radioactive release, but "some lesser event" is inevitable at some stage, without a "more vigilant precautionary approach... [being] ...adopted".
These revelations have surfaced at a sensitive moment, as the government's energy review is expected to be published within a fortnight, and both Tony Blair and Gordon Brown have spoken positively on the pressing need for a new generation of nuclear reactors (of some type yet to be disclosed). In papers from June 2005, an inspector concludes on the subject of the U.K.'s AGR power plants: "I judge that there is significant uncertainty in the likelihood and consequences for the core safety functionality posed by ... core damage. The assessor needs to assume worst case consequences of ... core damage unless the licensee is able to provide robust arguments." Yesterday, British Energy said that it had provided new evidence to the NSD. "If the health and safety executive were not confident in the safety of the reactor cores we would not allow the reactors to operate. The assessment report was part of the ongoing regulatory process ... The Nuclear Safety Directorate is monitoring closely British Energy's work on graphite and, where necessary, is influencing the scope and extent of the reactor core inspections that the company carries out. British Energy has also been working on methods to monitor the cores whilst the reactors are in service. This will provide added reassurance on the condition of the cores."
It is hard to know what actions exactly this rhetoric will translate into. Reading between the lines, it looks that the AGR's are "out" once and for all when they reach the end of their intended life-span, and so the "new generation" of reactors will most likely be of some other design. The whole issue has placed the matter of nuclear safety firmly back on the agenda facing any committee charged with weighing up the pros and cons of nuclear power: now, it is not only the matter of what to do with the nuclear waste, and aspects of terrorism that must be considered, but whether the public will find its sleep disturbed by dreams of a "British Chernobyl", unlikely though that may be. Once more, public relations are likely to become strained over the viability of nuclear power.