ML21069A237
| ML21069A237 | |
| Person / Time | |
|---|---|
| Issue date: | 03/16/2021 |
| From: | Mike Franovich NRC/NRR/DRA |
| To: | Louise Lund NRC/RES/DE |
| Gran, Z | |
| References | |
| RG 1.112, Rev 1 | |
| Download: ML21069A237 (4) | |
Text
March 16, 2021 MEMORANDUM TO: Louise Lund, Director Division of Engineering Office of Nuclear Regulatory Research Bowman, Gregory signing on beh FROM: Michael X. Franovich, Director of Franovich, Michael on 03/16/21 Division of Risk Assessment Office of Nuclear Reactor Regulation
SUBJECT:
RESULTS OF PERIODIC REVIEW OF REGULATORY GUIDE 1.112 This memorandum documents the U.S. Nuclear Regulatory Commission (NRC) staffs periodic review of Regulatory Guide (RG) 1.112, Revision 1, Calculation of Releases of Radioactive Materials in Gaseous and Liquid Effluents from Light-Water-Cooled Nuclear Power Reactors.
A review of the guide is enclosed with this memorandum.
This RG, issued in 2007, provides guidance for calculating annual average expected releases of radioactive material in gaseous and liquid effluents (i.e., normal source terms) from large light-water-cooled nuclear power reactors (LWRs). As discussed in Management Directive 6.6, Regulatory Guides, the staff reviews RGs periodically to ensure that the RGs continue to provide useful guidance.
Based on the results of the periodic review, the staff concludes that no changes to RG 1.112, Revision 1 are warranted at this time. However, the staff identified some technical or regulatory issues in the review that could warrant addressing in a future revision. A revision to the RG could benefit new reactor applications. With few light water reactor applicants expected in the coming years and significant staff resources necessary to revise the RG, the staff does not believe that a RG update is justified at this time. The staff will evaluate the need to revise the RG during the next periodic review.
CONTACT: Zachary Gran, NRR/DRA 301-415-5520
Enclosure:
As stated
ML21069A237 NRR-106 OFFICE NRR/DRA/ARCB NRR/DRA/ARCB: BC NRR/DRA: D NAME ZGran KHsueh MFranovich DATE 03/11/21 03/12/21 03/16/21 Regulatory Guide Number: 1.112, Revision 1
Title:
Calculation of Releases of Radioactive Materials in Gaseous and Liquid Effluents from Light-Water-Cooled Nuclear Power Reactors Office/division/branch: NRR/DRA/ARCB Technical Lead: Zachary Gran Staff Action Decided: Reviewed with issues identified for future consideration
- 1. What are the known technical or regulatory issues with the current version of the Regulatory Guide?
This RG endorses the American National Standards Institute (ANSI)/American Nuclear Society (ANSI) ANSI/ANS-18.1-1999, Radioactive Source Term for Normal Operation for Light Water Reactors. In 2016, the ANSI/ANS-18.1 standard was updated with new source terms for large light water reactors (LWRs). The NRC has not yet endorsed the ANSI/ANS-18.1-2016 standard and could possibly do so in a proposed RG update following the staffs review.
In addition to the updated source terms provided in ANSI/ANS-18.1-2016, the staff expects to gain new reactor licensing lessons learned on a proposed alternate method for source term development from the small modular reactor (SMR) Design Certification Application (DCA) currently under review. This proposed alternative method is used in lieu of the NRC endorsed GALE86 code and the ANSI/ANS-18.1-1999 standard for licensing large LWRs in the United States (U.S.). Additional guidance needs to be developed by the staff which would provide the acceptance and evaluation criteria for when an alternate method is proposed by an applicant or licensee. This guidance would also be applicable to advanced reactor designs.
- 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?
The primary use of this RG is for reactor licensing. There is little or no impact on internal and external stakeholders if the NRC endorsed GALE86 code and the ANSI/ANS-18.1-1999 standard continues to be used in licensing large LWR designs in the U.S.
However, the staff is not expecting any large LWR applications in the near future; instead, non-LWR and advanced reactor design applications are anticipated. Therefore, when an applicant or licensee uses calculation models, design parameters, and assumptions that differ from GALE86 and the ANSI/ANS-18.1-1999 standard, the alternative method requires additional review time and requests for additional information.
- 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?
An estimate of the effort needed to review relevant technical and regulatory issues of this RG and to consider new reactor licensing lessons learned from the SMR DCA currently under staff review is 1 FTE. This work can be performed by the staff without the need for contract support.
- 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)?
Reviewed with issues identified for future consideration.
- 5. Provide a conceptual plan and timeframe to address the issues identified during the review.
A revision to the RG could benefit new reactor applications. However, with few light water reactor applicants expected in the coming years and significant staff resources necessary to revise the RG, the staff does not believe that a RG update is justified at this time. In addition, NUREG-0016, Revision 2, Calculation of Release of Radioactive Materials in Gaseous and Liquid Effluents from Boiling-Water Reactors: GALE-BWR 3.2 Code (ADAMS Accession No. ML20213C728) and NUREG-0017, Revision 2, Calculation of Release of Radioactive Materials in Gaseous and Liquid Effluents from Pressurized-Water Reactors: GALE-PWR 3.2 Code (ADAMS Accession No. ML20213C729) describe use of the updated ANSI/ANS-18.1-2016 standard in the GALE 3.2 series of computer codes distributed by the NRC Radiation Protection Computer Code Analysis and Maintenance Program at https://ramp.nrc-gateway.gov/. The staff will evaluate the need to revise the RG during the next periodic review.
NOTE: This review was conducted in March 2021 and reflects the staffs plans as of that date. These plans are tentative and are subject to change.