Document: NRC Regulatory Guide
Document ID: 28bfa464-f1cc-4f82-9b3c-4cfbe773e040
Document Type: regulatory_guide
Title: Fresh and Spent Fuel Pool Criticality Analysis + HISTORY - HISTORY 08/2020 – DG-1373 , Proposed Revision 0
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2018/ML20182A788.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.240
CFR Part: 
CFR Title: 

Content:
nce of this RG. Licensees that already use DSS-ISG-2010-01 to demonstrate compliance with NRC requirements may continue using that guidance as long as they do not change their licensing bases relative to that guidance. Background Over the years, criticality analyses for LWR power plant spent fuel pool storage racks and fresh fuel vaults have increased in complexity. Various changes have reduced safety margins relative to the regulatory requirements in 10 CFR 50.68(b), such as high-density storage racks, increased enrichment, and degradation of neutron absorber materials. The lack of explicit NRC guidance and the lack of standardization in spent fuel pool storage requirements led to multiple licensing reviews that exceeded normal review time frames. Therefore, the NRC found it necessary to provide guidance to support the review of methods for performing criticality analyses submitted for demonstrating compliance with 10 CFR 50.68(b). These analyses are integral to the technical foundation for the design of nuclear fuel storage structures, systems, and components, and the associated technical specifications in applications (i.e., license amendment requests) submitted to the NRC for review and approval. In 2011, the NRC issued DSS-ISG-2010-01 to address this need. The intent of DSS-ISG-2010-01 was to clarify ambiguity in existing guidance and to build upon lessons learned based on licensing reviews at the time. While DSS-ISG-2010-01 provided updated guidance to the NRC staff that was responsive to the increased complexity of more recent spent fuel pool license application analyses and operations, it did not consider all aspects of performing criticality analyses of fuel storage at LWR power plants. Therefore, the staff believed that a comprehensive and more specific guidance document for performing criticality analyses of fuel storage at LWR power plants was still necessary. NEI, in collaboration with the Electric Power Research Institute (EPRI), developed NEI 12-16 to