In both the Unites States and United Kingdom, the EPR-design is awaiting approval from the nuclear regulatory bodies. A whole list of outstanding issues have to be addressed by EDF and Areva in the UK and in the US, a new revised schedule shows the EPR is unlikely to receive design certification by the nuclear regulator before the end of 2014.
On 14th December 2011 the United Kingdom’s Office for Nuclear Regulation (ONR) and Environment Agency granted interim Design Acceptance Confirmations (iDACs) and interim Statements of Design Acceptability (iSoDAs) for the UK EPR and the AP1000 reactor designs. The ONR‘s interim approval for the UK EPR came with a long list of caveats – 31 so-called “GDA Issues”.
UK: Generic Design Assessment
Since then EDF and Areva have closed out only one of the 31 “GDA Issues” According to the ONR’s latest Generic Design Assessment (GDA) quarterly report — issued on 24th May for the period ending March 31 — EDF and Areva have fallen substantially behind in the number of responses to the GDA Issue resolution to date. ONR said the shortfalls in deliverables “are having an effect on our progress and on our ability to use the (outside) technical support contractors we had programmed to support our work, as their availability is not always guaranteed when the original assessment dates have been missed.”
The GDA Issue resolution plan Areva and EDF agreed to with ONR called for all GDA Issues to be resolved by November 2012. This will now extend into 2013. Areva and EDF have committed to deploy additional resources and submit a revised GDA Issue resolution plan, but ONR is still waiting to receive it. Building magazine reported in its May 25 issue, that the process is three months behind schedule.
Among the 30 remaining GDA Issues that have yet to be closed is one on the EPR’s control and instrumentation (C&I) system, which was the subject of an unprecedented joint regulatory letter from the UK, France and Finland in 2009. The French safety regulator, the Autorité de Sûreté Nucléaire, on April 16 removed its reservations about the digital C&I system for the EPR, but the ONR is still waiting for some deliverables due from EDF and Areva on the C&I GDA Issues.
The process of working to close out the 31 “GDA Issues” is leading to some design changes, according to ONR. “We have received a number of modification proposals to amend the EPR design to take account of the solutions proposed to some of the GDA Issues,” ONR said in its latest quarterly report, citing two examples. There are two related design changes to the main coolant loop pipework and both improve the quality of inspection achievable during construction and operation.
US: delay EPR certification
Design certification in the US is also likely to be delayed: the EPR is unlikely to receive design certification by the US nuclear regulator, NRC, before the end of 2014, and even that will “present a challenge”. Design certification for the EPR had earlier been targeted for June 2013. Areva submitted its application for certification of the EPR design in December 2007 aiming to clear the way for reactors of that generic type to be built anywhere in America subject to site-specific licensing procedures and the issue of a combined construction and operating licence (COL). Four COL applications referencing the EPR have already been submitted to the NRC.
The NRC has issued a new review schedule to allow Areva to respond to outstanding technical issues previously raised by the NRC and to provide additional information related to new post-Fukushima requirements issued by the commission in February.
Under the revised schedule, Areva is expected to submit to the NRC, by 30 August 2013, details about how the EPR design meets the post-Fukushima requirements and all outstanding technical issues should be resolved by 1 November 2013.
Matthews told Areva that there is "no margin" in the schedule to allow for the timing of "critical milestones" to be changed and still achieve certification by the end of 2014. He added, "While the staff has increased its attention to meeting the schedule, we will ensure that the design meets all applicable NRC regulatory requirements before we proceed to certification rulemaking."
In July 2010, the NRC highlighted two areas of concern related to the EPR design. These centered on design complexity and independence issues: each safety division within the system must be able to perform its function without relying on data from outside and must also be protected from adverse external influences. Areva needs to demonstrate to the regulator's satisfaction that these issues have been addressed, and show that data exchange between systems will not adversely affect safety.
Areva has already described proposed design changes intended to reduce the level of complexity as well as to address some of the intercommunication issues. However, Areva has notified the NRC of some areas where its feels that design changes are not advisable, and these appear to be the areas which the regulator feels may not meet its standards.
Source: NuClear News No.41, June 2012 / World Nuclear News, 31 May 2012
Contact: Pete Roche