(Montel) EDF has said it found indications of possible stress corrosion on the auxiliary circuits of four French nuclear power reactors totalling 4.8 GW in capacity, namely Chinon 3, Cattenom 3, Flamanville 2 and Golfech 1.
The units are among six reactors that EDF considers as "priority" for these checks, with the other three being Flamanville 1 (1.3 GW) and Bugey units 3 and 4 (880 MW each).
Meanwhile, inspections carried out on the safety injection system circuit at Golfech 1 (1.3 GW) during planned maintenance also detected indications of possible corrosion, EDF added.
A spokeswoman told Montel on Tuesday that the utility was carrying out further investigations to find out whether it was corrosion or not.
Growing number of units affected
Previously, EDF identified corrosion issues at five other units at its Civaux, Chooz and Penly nuclear power stations.
EDF said the inspections on these five reactors remained ongoing but did not provide further information. All five units are also offline.
The unplanned outages have forced the firm to cut its annual nuclear output target to a 30-year low.
For the remaining 45 reactors in the French fleet, the checks will be carried out during the shutdowns already scheduled for maintenance and refuelling until 2024, EDF said.
On Tuesday morning, nuclear production in France reached 32 GW, down 6.4 GW from the same time a year ago.
This is an updated version of story published at 09:26 after EDF clarified that there are indications of "possible" corrosion.