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More Problems for the EPR, NuClear News April 15  The French Nuclear Safety Regulator, ASN, announced on 7th April that it had been informed by AREVA of an anomaly in the composition of the steel in certain zones of the reactor vessel head and reactor vessel bottom head of the Flamanville EPR. (1) These fabrication defects are very serious mechanical faults. Quality inspectors found an abnormally high concentration of carbon in steel parts capping the reactor vessel’s top and bottom during a series of tests carried out by French nuclear company Areva, which is building the reactor. The excessive carbon would lead to “lower than expected mechanical toughness values”, nuclear regulator ASN said in a press statement on its website. This obviously raises a question-mark over the safety case for the EPR (European Pressurized Water Reactor) currently under construction in Normandy. The reason why a well‐known material heterogeneity problem was not mastered during the forging of the pieces at Areva’s Le Creusot plant has yet to be investigated. The reason why the defects were detected or publicly released so late, at a moment when the pressure vessel was already in place in the reactor building, also needs to be scrutinised.

Areva will face a very difficult challenge in justifying the safety case of the flawed pressure vessel. The only alternative to demonstrating safety in spite of the faults would be to repair or replace the faulty components, which appears hardly feasible and particularly expensive in the case of the bottom piece. Therefore the future of the entire Flamanville-3 project is at stake. The No2NuclearPower nuClear news No.73, April 2015 3 problem has also international implications, since at least some of the upper and/or lower heads of the Taishan-1 and 2 EPRs, under construction in China, are apparently also concerned. …..http://www.no2nuclearpower.org.uk/nuclearnews/NuClearNewsNo73.pdf