Flamanville EPR : update

EDF has reviewed the position of the Permanent Group of experts for nuclear pressure equipment (GP ESPN) on the quality deviations affecting the welds located on the main steam transfer pipes covered by the break preclusion principle of the Flamanville 3 EPR, made public on the 11th of April 2019.

The recommendations and solution avenues suggested by the Permanent Group of experts could have an impact on the commissioning schedule and construction cost.

EDF is pursuing its exchanges with the Nuclear Safety Authority (ASN), which will deliver, in the upcoming weeks, its ruling regarding how to proceed further with this matter.

A detailed update of the schedule and construction cost of the Flamanville EPR will be given after the ASN ruling has been published.

Details on the investigation procedure :

On 9 April 2019, ASN convened its permanent group of experts for nuclear pressure equipment (GP ESPN) as part of the investigation into quality deviations affecting the welds located on the main steam transfer pipes covered by the break preclusion principle of the Flamanville 3 EPR :

• On 3 December 2018, EDF submitted to ASN a technical file presenting the procedures for repairing and upgrading the main secondary circuit welds, which had showed deficiencies with respect to the break preclusion requirements, as well as for the specific justification method for the 8 welds located in the reactor containment building structure.
• The file has been subjected to investigation from the ASN, with technical support from the IRSN.
• Based on this investigation, the discussions were conducted in a GP ESPN meeting attended by EDF, who presented the fact chronology, their analysis and the methods for dealing with the deviations. EDF has endeavored to answer all the questions of the permanent group of experts for the technical instruction of this file.