United States Nuclear Regulatory Commission - Protecting People and the Environment

ESBWR Design Certification Review

On December 2, 2010, GEH submitted Revision 9 of the ESBWR DCD. Revision 6 of the ESBWR Probabilistic Risk Assessment (PRA) is also publicly available. See NEDO-33201, Revision 6.

On March 9, 2011, the staff issued the final safety evaluation report and final design approval for the ESBWR standard design. The final safety evaluation report was subsequently published as NUREG-1966, "Final Safety Evaluation Report Related to the Certification of the Economic Simplified Boiling Water Reactor Standard Design," in April 2014.

In late 2011, while the NRC staff was preparing the final rule, issues were identified with the ESBWR steam dryer, a non-safety component. These issues called into question certain conclusions in the staff's safety review. The NRC conducted an audit of the steam dryer design methodology supporting Chapter 3 of the ESBWR DCD. The purpose of the on-site audit was to review documentation presented by GEH that addressed key errors in the steam dryer design methodology. The NRC issued requests for additional information (RAIs). Resolution of these issues required additional analyses by the applicant and review by the NRC staff in order for the NRC staff to conclude the design is acceptable for certification. Responses to all RAIs were received in December 2013. An Advanced Supplemental FSER was issued to the ACRS on February 12, 2014.

By letter dated April 1, 2014, GEH submitted Revision 10 of the ESBWR DCD. A supplemental final safety evaluation report will include the NRC staff's safety review of the steam dryer issues. The DC rulemaking process has resumed and the final rule is planned for completion later this year.

Page Last Reviewed/Updated Thursday, May 01, 2014