ML23107A201
| ML23107A201 | |
| Person / Time | |
|---|---|
| Issue date: | 05/04/2023 |
| From: | Fitzgerald M NRC/NRR/DRO |
| To: | |
| References | |
| RG 1.79, Rev 2 | |
| Download: ML23107A201 (2) | |
Text
Regulatory Guide Number:
RG 1.79, Revision 2
Title:
Preoperational Testing of Emergency Core Cooling Systems for Pressurized-Water Reactors Office/Division/Branch:
NRR/DRO/IQVB Technical Lead:
Michael Fitzgerald Staff Action Decided:
Revise
- 1.
What are the known technical or regulatory issues with the current version of the Regulatory Guide (RG)?
Regulatory Guide (RG) 1.79 describes the general scope and depth that the staff of the U.S. Nuclear Regulatory Commission (NRC) considers acceptable for demonstrating compliance with the NRC regulations as they pertain to preoperational testing of emergency core cooling systems (ECCS) for pressurized-water reactors. Since the publication of the RG in 2013, the NRC staff has been informed of the potential for the submittal of construction permits in support of light-water cooled related designs. To that end, the NRC staff is looking to update preoperational testing guidance for ECCS to include recent lessons learned and address advanced Small Modular Reactor (SMR) designs. Additionally, the NRC staff has determined that previously referenced international standards have been revised/superseded. As such, it is the NRC staffs intent to update the guidance to reflect the new international standard.
- 2.
What is the impact on internal and external stakeholders of not updating the RG for the known issues, in terms of anticipated numbers of licensing and inspection activities over the next several years?
For new reactors, the NRC staff anticipates the submittal of 1-2 applications in the next several years. Since there are no issues currently identified with the technical content in the RG, there will be no impact on these licensing activities.
- 3.
What is an estimate of the level of effort needed to address identified issues in terms of full-time equivalent (FTE) and contractor resources?
The NRC staff requires approximately 0.50 FTE to complete combination and update related activities. No contractor support is anticipated.
- 4.
Based on the answers to the questions above, what is the staff action for this guide (Reviewed with no issues identified, Reviewed with issues identified for future consideration, Revise, or Withdraw)?
Revise.
- 5.
Provide a conceptual plan and timeframe to address the issues identified during the review.
Based on recent ECCS preoperational testing performed and standard designs approved since the previous revisions, it is the NRC staffs intent to identify lessons learned from previous ECCS preoperational testing, address specific concerns or challenges with approved standard designs, and provide guidance for ECCS in PWR SMRs. Additional changes planned include updating and harmonization with superseded international standards. It is intended that a draft guide will be made available for public comment in calendar year 2024.
NOTE:
This review was conducted in April 2023 and reflects the staffs plans as of that date. These plans are tentative and subject to change.