Flamanville construction continues while vessel tests due

20 April 2015

Work is continuing at the construction site of an EPR unit at Flamanville in northern France, French utility EDF said yesterday. Preparations are underway to conduct further tests on the unit's vessel after anomalies were identified in the composition of the steel in certain parts of it.

The French nuclear regulator, the ASN (Autorité de Sûreté Nucléaire), announced on 7 April it had been informed by Areva that chemical and mechanical tests conducted in late 2014 on a reactor pressure vessel (RPV) head similar to that of the Flamanville EPR had revealed an area with high carbon concentration. This, it said, has led to "lower than expected mechanical toughness values".

In a statement yesterday, EDF noted that revised mechanical specifications for nuclear pressure equipment were introduced in 2005, with which equipment for the Flamanville EPR must comply.

The company said, "Areva and EDF are currently preparing the work on a new series of tests aimed at demonstrating the compliance of Flamanville 3 equipment to these new standards. In accordance with the regulation, this program will be submitted to ASN for approval."

However, it added, "On the basis of the information available at this stage, EDF can confirm that work can continue on Flamanville's EPR site."

Earlier, EDF and Areva said that its teams were "working to perform the additional tests as soon as possible, following approval by the ASN on the test conditions, and to provide the safety authority with the necessary information to demonstrate the safety and quality of the corresponding equipment."

Areva is required to "demonstrate that the phenomena in question on the RPV upper and bottoms head of the Flamanville EPR NPP are clearly identified, controlled and do not affect other areas of these components than those identified", ASN said in an 8 April technical note.

Construction work began on the 1650 MWe unit at the Normandy site in December 2007. The reactor vessel was installed in January 2014. The unit is currently expected to start up in 2017.

EPRs are also under construction at Olkiluoto 3 in Finland and Taishan 1 and 2 in China. Olkiluoto 3 has been under construction since 2005 and has seen several revisions to its start-up date, which is now expected by 2018. Taishan 1, which has been under construction since 2009, is expected to start up in 2016, while Taishan 2 is scheduled to begin operating a year later. Two further EPRs are planned at Hinkley Point in the UK.

Researched and written
by World Nuclear News