ML23088A259
| ML23088A259 | |
| Person / Time | |
|---|---|
| Issue date: | 03/31/2023 |
| From: | Jason White NRC/NRR/DEX/EXHB |
| To: | |
| Shared Package | |
| ML23088A231 | List: |
| References | |
| RG-1.023, Rev 1 | |
| Download: ML23088A259 (2) | |
Text
Regulatory Guide Periodic Review Regulatory Guide Number:
1.23, Revision 1
Title:
Meteorological Monitoring Programs for Nuclear Power Plants Office/division/branch:
NRR/DEX/EXHB Technical Lead:
Jason White 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 (RG)?
RG 1.23, Revision 1, Meteorological Monitoring Programs for Nuclear Power Plants dates to 2007 (Agencywide Documents Management System Accession No. ML070350028). This Regulatory Guide (RG) describes a suitable onsite meteorological measurements program to collect the basic meteorological data needed to (1) determine the environmental impacts of a nuclear power plant, (2) perform consequence assessments supporting routine release and design-basis accident evaluations, and (3) support emergency preparedness programs at power reactor sites.
Technical issues to be addressed in future revisions to RG 1.23 include updates to the atmospheric dispersion models used to estimate impacts due to design-basis accident and routine radiological releases and considerations on how to address potential deployment of small modular reactors (SMRs) in remote locations such as extreme cold climates. Changes to the atmospheric dispersion models may necessitate expanding the guidance to address: possible different approaches for characterizing atmospheric stability; identification of measurement elevations depending on the height of above-ground buildings, release characteristics (i.e., buoyancy and momentum), and expected height of temperature inversions; equipment specifications, frequency of maintenance and calibration activities, and data transmission and surveillance frequency tailored to that type of environment; and provisions for possible changes in measuring dispersion-related characteristics between cold and warm seasons.
Regulatory-related issues to be addressed in future revisions to RG 1.23 include reconciliation of any identified discrepancies between RG 1.23 and other directly related guidance documents (i.e., NUREG-0800 Sections 2.3.3, 2.3.4, and 2.3.5 which, in turn, are directly linked to the accident and routine release-related dispersion modeling approaches covered in RGs 1.145, 1.194, and 1.111, respectively). Other potential regulatory-related issues include the potential need to: update reference citations; clarify terminology; expand the guidance to better explain information related to the data validation and handling process; add guidance related to the expected level of detail to be provided when an onsite meteorological tower is relocated and/or meteorological system equipment is upgraded; and evaluate the latest revision of ANSI/ANS-3.11-2015 (R2020) to determine to what extent that industry standard should be endorsed.
- 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?
There is no immediate need for revising the RG 1.23 at this time. The staff will revise this guidance to correspond to future revisions of RGs 1.145, 1.194, and 1.111, and the NUREG-0800 Sections 2.3.3, 2.3.4, and 2.3.5. There should not be an impact on stakeholders as the staff has procedures in place to address licensing and inspection activities over the next several years.
- 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 staff anticipates an approximate level of effort of 0.2 FTE for the future revision of RG 1.23.
- 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.
- 1. Identify the portions of RG 1.23 that need revision.
- 2. Review the pertinent consensus standards.
- 3. Identify dependencies between any items both within the RG itself as well as with RGs 1.145, 1.194, and 1.111 and the NUREG-0800 Sections 2.3.3, 2.3.4, and 2.3.5.
- 4. For any additional technical problems that may arise based on this review, identify which may be already addressed in other RGs and perform literature review or calculations as necessary to satisfy the problem.
- 5. Review the revised RG to ensure agency standards are met.
- 6. A revision to the RG is planned prior to the next periodic review in 2033.
NOTE: This review was conducted in March 2023 and reflects the staffs plans as of that date. These plans are tentative and are subject to change.