Construction of a third reactor at the plant, which is about 30 miles from Jersey, started in 2007 and is being carried out by manufacturers Areva.
The project has been dogged with problems, including concerns about potentially faulty components.
In 2015, Areva warned Autorité de Sûreté Nucléaire – the French nuclear regulator –that anomalies had been detected in the steel covering the reactor.
They also said that excessive quantities of carbon in the steel in the top and bottom of the reactor's vessel, which forms a shell around it, could cause cracks in the structure.
Full report in Saturday's JEP.
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