The UK nuclear regulator said Wednesday it expects both the Areva EPR and the Westinghouse AP1000 reactors to have unresolved safety issues when the generic design assessment, or GDA, program completes next year. In a quarterly progress report released Wednesday, the NII said it has potential open issues in 10 out of 18 topical areas on the Areva EPR design review and in 16 out of the 18 topical areas on the Westinghouse AP1000 design.
The GDA program was set up to issue design acceptance confirmations, or DACs, to the reactor vendors, which would see the regulator sign off on all but site specific licensing issues. The DAC could then be referenced in site license applications by utilities building the reactors.
But the program has been plagued by delays resulting from NII staff shortages and a failure on the part of the reactor vendors to satisfy the regulator's queries.
As the program evolved since 2007, the NII said that, instead of issuing DACs, it would issue "interim DACs" with "GDA issues." GDA issues would have to be resolved prior to the start of nuclear island construction, the NII has said.
Both the AP1000 and the Areva EPR will have "GDA issues" outstanding at the end of the program, the NII said.
However, the NII also said that such open issues would not adversely affect existing plans by utility operators to build the reactors, including specifically EDF Energy's plans to build its first EPR at Hinkley Point C, starting in 2013.
In the case of both reactors, the NII said "we do not anticipate repeating any assessment of safety case arguments [in the site licensing phase] that we have already confirmed as acceptable during GDA. The one caveat to this statement would be if substantial differences to the generic safety cases are introduced [during site licensing] by the requesting parties or other operators/licensees."
The requesting parties are Westinghouse for the AP1000, and Areva and EDF for the EPR.
Nonetheless, NII said some of the outstanding issues on both designs will require design changes and "in these cases we are seeking to agree the principle aspects of the changes" before the end of the program in June 2011.
In a joint statement, Areva and EDF said they were "encouraged" by the latest progress report.
"We welcome their assertion that the EPR reactor design is capable of being shown to be acceptable in the UK and specifically that the plans declared by EDF for UK EPRs at Hinkley Point would not be adversely affected by clearance of any GDA issues," they said.
Similarly, Westinghouse said in a statement Wednesday that it welcomes "the continued recognition from [NII] that they have not identified any showstoppers that could prevent the AP1000 from [being] licensable in the UK."
"We are in the midst of the peak of activity on GDA, and substantial progress has been made across the board in the period covered by this report. Nonetheless, there is still a very considerable amount of work to do and we remain committed to delivering this so that a positive GDA outcome can be reached in June 2011," it said.