The US Nuclear Regulatory Commission (NRC) has told Dominion and Luminant that their licence applications to build at North Anna and Comanche Peak will be delayed by some 18 months after changes in the design of Mitsubishi Heavy Industries' (MHI's) Advanced Pressurized Water Reactor (APWR).
|A cutaway of the US-APWR design (Image: NRC)
Luminant is proposing the 1700 MWe APWR design for units 3 and 4 at the Comanche Peak nuclear power plant in Texas, while Dominion plans to use the design for the proposed third unit at North Anna plant in Virginia.
MHI submitted its design certification application for the US-APWR to the NRC in late December 2007 and this was formally accepted in March 2008. However, MHI has since made structural changes to the US-APWR design which required performing a new seismic analysis. The NRC is currently reviewing the new seismic re-analysis technical reports submitted by MHI. Last month the company "proposed a number of new strategies for expediting the resolution of the remaining technical issues associated with the review of the design certification (DC) application," the NRC said.
In a letter to Luminant dated 2 March, the NRC told the company that its review of Luminant's application to build Comanche Peak units 3 and 4 had been rescheduled, saying that the change reflects the commission's new plans for reviewing the US-APWR. The NRC noted that the application review for the two new units "encompasses both the safety and the environmental reviews. The environmental review schedule currently remains unchanged and supports the issuance of a final environmental impact statement by 23 May 2011." However, the NRC added that it "is unable to issue the safety evaluation (SE) for the reference COL before the SE for the DC is issued."
Under the NRC's new schedule for reviewing Luminant's application, the safety review for Comanche Peak units 3 and 4 will be completed by June 2013, instead of the earlier target of December this year. The subsequent mandatory hearing process is expected to be completed by November 2013.
In May 2010, Dominion selected the US-APWR design for the potential third unit at its North Anna plant, having previously referenced GE-Hitachi's Economic Simplified Boiling-Water Reactor (ESBWR) in its COL application.
In another 2 March letter the NRC informed Dominion that the review of its COL application – which references both the US-APWR design and the Comanche Peak application – has also been rescheduled. The NRC said that "the environmental schedule supports issuance of a draft supplemental environmental impact statement by March 2012 and a final supplemental environmental impact statement by October 2012."
The safety review for North Anna unit 3 is now expected to be completed in July 2013, instead of February 2011. The subsequent mandatory hearing before the commission is expected to be completed by November 2013.
The NRC told Luminant that the schedule of its COLA review could subsequently be revised again depending on how the design certification process of the US-APWR progresses. Likewise, Dominion's review schedule could also change depending on both the DC process and on Luminant's COLA review schedule.
Researched and written
by World Nuclear News