Document: NRC Regulatory Guide
Document ID: 6ab6a5e8-47ac-40c0-8c91-837b4e6f0026
Document Type: regulatory_guide
Title: Physical Models for Design and Operation of Hydraulic Structures and Systems for Nuclear Power Plants + HISTORY – HISTORY 09/2014 – Periodic Review of Revision 2 – Reviewed with issues for future consideration 03/2009 – Periodic Review of Revision 1 – Revise 07/2008 – DG-1198 , Proposed Revision 2 (Rev. 2)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0810/ML081080301.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.125
CFR Part: 
CFR Title: 

Content:
he Regulatory Guide 1.125 Under this alternative, the NRC would update Regulatory Guide 1.125, taking into consideration the current risk-informed, performance-based approach to licensing and improved modeling methods and state-of-the-art analytical and computational methods. One benefit of this action is that it would enhance the safety of the hydraulic structures by identifying and eliminating potential problems, thus reducing construction and maintenance costs. Implementation of the revised guidance in this proposed draft regulatory guide is useful where hydraulic structures and systems are of unusual design or configuration and hydraulic parameters cannot be adequately evaluated by state-of-the-art analytical or computational methods. In addition, physical models can incorporate the appropriate governing equations without the simplifying assumptions that are often necessary in analytical or numerical models. Physical hydraulic models may also be used to establish conservative and reasonable design or operating bases for sites, structures, or systems involving thermal and erosional problems. The cost to the NRC would be the one-time cost of issuing the revised regulatory guide (which is expected to be relatively small), and applicants would incur little or no cost. 4. Conclusion Based on this regulatory analysis, the staff recommends that the NRC revise Regulatory Guide 1.125. The staff concludes that the proposed action will enhance the safety of hydraulic structures through improved design review and verification. It could also lead to cost savings for the industry, especially with regard to applications for standard plant design certifications and combined licenses.