The biggest corrosion damage discovered to date in a French nuclear reactor is likely to lead to full inspections of other nuclear power plants. The French nuclear safety authority on Wednesday asked the operator of the EDF plant to “detect possible new cases” and “adjust its control strategy”.
exceptionally long
The regulator had announced the night before that EDF had discovered an unusually long and deep crack in a pipe at the Penly nuclear power plant in the English Channel. It is therefore a crack 15.5 centimeters long, which corresponds to a quarter of the line’s diameter. It is also 23 millimeters deep with a tube thickness of 27 millimeters. “It’s not a crack … it’s a problem,” agency head Bernard Doroszczuk told a Senate hearing on Wednesday.
“Due to the possible consequences and the increased probability of rupture”, the authority classified the rupture as a level two accident on the INES scale for evaluating nuclear events. This does not put people or the environment at risk. Level two incidents are relatively rare, there was only one last year.
The reactor is currently shut down. It should be increased again in May. “The crack appeared where you didn’t expect it,” nuclear expert Yves Marignac told the AFP news agency. It is a line in the emergency refrigeration system through which heated water is routed in an emergency.
construction error
So far, EDF has mostly checked the lines of the emergency cooling system, through which cold water would be fed, Marignac said. The extent of the crack is concerning. “It’s almost a leak,” he said.
According to the Nuclear Safety Authority, the crack is due to an error in the construction of the nuclear power plant. “People would bend the pipes to weld them together, then the welds would fail and they would be fixed again,” explained Doroszczuk. This is an “unacceptable course of action”.
Since late 2021, hairline cracks up to six millimeters deep have appeared in pipelines at several newer nuclear power plants in France. EDF withdrew part of the reactors from the network for necessary repairs. Repairs were delayed because France lacked the necessary specialists. All 56 reactors are to be examined for possible corrosion damage. EDF announced late last year that it had overcome the corrosion damage crisis.
corrosion problems
According to the Nuclear Safety Agency, EDF also updated its information on corrosion problems in nuclear reactors at Cattenom, Civaux and Chooz. These were classified as a level one “disorder” by the agency on the INES scale. Details were not initially known.
Due to ongoing problems with its aging nuclear power plant, France produced less electricity last year than it had in three decades. President Emmanuel Macron wants to lay the foundation stone for the first two of six new nuclear reactors to be built at Penly during his term.