Within the program of explorations of old nuclear power plants, the Civaux Nuclear Power Plant is currently closed, and the accident occurred during tests when a device to cool the water circuit failed, according to EDF explanations. This apparatus did not undergo a 200 bar pressure test, so a steam tap escaped releasing 1.5 m3 of water per hour. Steam is transformed into water when cooled and, according to the company, 80 m3 of radioactive leaks have been recovered and stored for the time being.

According to those in charge of the plant, no contaminated injuries or radiation have occurred and no radioactive contamination has been detected outside the nuclear construction. In the contaminated room, 7.5 times the radiation that workers can withstand has been measured. However, the technicians responsible for nuclear safety say that this is an unprecedented accident and that what has happened will have to be analysed very well.

In an exploration last year, a corrosion phenomenon was also observed as pressure increased in this reactor, but according to the EDF the current accident has not occurred due to the rupture of a welding. This plant has two editors, one started in 1997 and the other in 1999. After the exploration had to be restarted in January, but this accident would delay opening.