Document: NRC Regulatory Guide
Document ID: 7500cda6-62ab-4b82-85bd-1dbf504d108d
Document Type: regulatory_guide
Title: Flood Protection for Nuclear Power Plants (Rev. 1)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2106/ML21068A405.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.102
CFR Part: 
CFR Title: 

Content:
Enclosure Regulatory Guide Periodic Review Regulatory Guide Number: 1.102, Revision 1 Title: Flood Protection for Nuclear Power Plants Office/Division/Branch: RES/DE/SGSEB Technical Leads: Joseph Kanney, Kenneth See Staff Action Decided: Revise 1. What are the known technical or regulatory issues with the current version of the Regulatory Guide (RG)? Flood protection features and procedures for civil infrastructure have evolved considerably since the current revision of RG 1.102 was issued in 1976. Perceptions of the risk that external flooding may pose to nuclear power plants (NPPs) has also evolved considerably during this time frame, based on operational experience of flooding events at several NPPs. Examples include: • 1999 Extratropical cyclone and subsequent coastal flooding at Blayais (France) • 2011 Tsunami and subsequent coastal flooding at Fukushima Daiichi (Japan) • 2011 Seasonal rainfall and snowmelt induced Missouri River flooding at Fort Calhoun • 2014 Locally heavy precipitation and subsequent flooding at St. Lucie • 2019 Seasonal rainfall and snowmelt induced Missouri River flooding at Cooper In addition, proposed NPP designs, as well as potential applications and siting locations are rapidly evolving away from large light-water reactors (e.g. small modular reactors, micro reactors, non-light-water reactors). In updating RG 1.102, some of the technical issues that should be considered include: • To the extent possible, guidance should be technology neutral (with respect to reactor design) • Guidance should be broad and flexible to accommodate new and different applications and siting locations envisioned for small modular reactors and microreactors • Guidance should emphasize the desirability of permanent, passive protection in order to minimize risk owing to unreducible uncertainties in hazard forecasting and mobilization of temporary or active flood protection features. However, the appropriate role of temporary and/or active flood