June 27, 2008
Mr. Robert Sisk, Manager
Licensing and Customer Interface
Regulatory Affairs and Standardization
Westinghouse Electric Company
P.O. Box 355
Pittsburgh, PA 15230-0355
SUBJECT: REVIEW SCHEDULE FOR AP1000 REVISION 16 (DOCKET 52-006)
Dear Mr. Sisk:
Your letter of May 20, 2008, requested the U.S. Nuclear Regulatory Commission (NRC) to confirm that uncertainty in the review schedule for the AP1000 design certification amendment has been removed as a result of Westinghouse submittals on screen design/analysis and on bracketed Technical Specification items. These items were referred to in our February 15, 2008, letter establishing the review schedule. NRC agrees that the submittals identified in that letter were completed and submitted by Westinghouse on schedule. However, on June 3, 2008, you withdrew information that was necessary to address down-stream effects in the core.
The information addressing down-stream effects in the core is an important consideration in addressing the overall debris generation and long-term recirculation cooling. The June 3, 2008, submittal withdrew design basis information and did not provide new supporting information to replace the withdrawn information. As the staff discussed with you, the information provided in your June 3, 2008, letter is insufficient. It is our understanding that you wish that we identify necessary additional information in the form of requests for additional information (RAIs). The staff is proceeding with that approach. Therefore, although the submittals have allowed the staff to begin review of these issues, uncertainty remains with respect to completion of the long-term cooling review.
In addition, there remains uncertainty about the schedule outlined in the February 15, 2008, letter in light of changes. This uncertainty is created as a result of changes in the scope of work of the review requested by Westinghouse since developing that schedule, and delayed submittals. The scope changes include:
- Change to Integrated Head Package design (to be submitted in June)
- Revision to 50.46 analyses (see February 15, 2008, letter from Westinghouse) (to be submitted in June)
- Revised analysis for containment external pressure (submitted on May 12, 2008 as RAI-TR9-08)
- Revised seismic analyses for rack design (TR44 and 54), and for critical sections (TR57) (to be submitted in June)
- Various impact reports (GLE series)
The delayed submittals include some revised Technical Reports or Request for Additional Information (RAI) responses that have been or are projected to be submitted later than originally planned. These changes alter the basis for the review schedule we originally formulated. The staff understands that some changes in scope are necessary and may improve the design, and it is not our intent to discourage improvement in the design or analytical methods. We also understand that some submittals may need to be delayed for a variety of causes. Regardless, changes such as these do impact our planned reviews and affect ongoing reviews or require rearview of completed reviews. Given the current workload for all application reviews in the Office of New Reactors, introducing new work or delays in providing information as expected creates planning, scheduling and resource availability issues. As a consequence, the duration of your review may have to be extended in order to integrate new or delayed work into our work planning system. Assuming you provide the above information as committed, our goal is to inform you of changes to the schedule by August 30, 2008.
Thomas Bergman, Deputy Director
Division of New Reactor Licensing
Office of New Reactors