France’s Autorite de Surete Nucleaire (Nuclear Safety Authority - ASN) on 31 published extracts from 10 years of correspondence in which it had warned about safety issues at Areva-owned nuclear foundry Creusot Forge.
Commercial production at the foundry was stopped in late 2016 after ASN discovered manufacturing irregularities and forgery of tracking documentation. Two of EDF's reactors have been shut for months following the discovery of problems with components manufactured by Creusot Forge. In a letter to EDF dated 12 December 2005, ASN highlighted manufacturing irregularities at the foundry, which it said raised questions about the quality of its work, and urged EDF to closely monitor safety rules there.
Publication of the letters came after a report by radio station France Inter which said EDF and Areva had allowed Creusot Forge to manufacture the base and cover for the reactor vessel for unit 3 of the Flamanville NPP, ignoring ASN's warnings. Despite several more warnings in subsequent years, Creusot Forge manufactured the parts for the Flammanville unit, which were installed in the reactor in 2014. In Areva finally discovered in 2015 that there was a problem with excessive carbon concentrations in the components, which weakened the steel. ASN must now rule on whether the reactor, which is scheduled for completion late next year, can operate safely. ASN said it would rule on the issue "this summer".