Nuclear Reactor’s Future In Doubt After Discovery Of Cracks In Bricks

‘More safety questions have been raised over Britain’s ageing nuclear reactors after cracks were found in bricks that make up the reactor core at EDF Energy’s Hunterston B power station. The French state-backed company insisted that the cracks at the 38-year old reactor in North Ayrshire were to be expected and did not pose any safety risks. However, experts said that the discovery during routine maintenance cast doubt over whether the reactor could continue to operate into the 20205, as EDF Energy hopes. About 6,000 graphite bricks make up the stack around the reactor core and they degrade as they become more exposed to radiation. If they crack or become distorted, there could be problems inserting the control rods that shut down the reactors in an emergency. If the stack moves even a fraction out of place, cooling flows for the reactor cores could be blocked and cause it to overheat. EDF Energy will submit its next safety case for Hunterston B to the ON R in Ianuary2017. It will have to demonstrate to the regulator that it will be safe to continue to operate the reactor. lohn Large, a nuclear consultant, said that degradation of the graphite bricks was a common issue to all EDF Energy’s 14 AGR reactors, adding it was impossible to detect the cracks in all the bricks, which cannot be replaced. “EDF has been trying to cure this generic problem,” he said. “You can’t confidently say that these reactors will pass a safety review.” ‘ [Once again, the ONR will, no doubt, accommodate the nuclear industry before our safety, just as it did with Dungeness B’s reactor cracked graphite bricks recently. —Ed.]

From The Times 7th October 2014