ML25258A264
| ML25258A264 | |
| Person / Time | |
|---|---|
| Issue date: | 09/17/2025 |
| From: | NRC/NRR/DNRL/NCSG |
| To: | |
| Shared Package | |
| ML25258A263 | List: |
| References | |
| Download: ML25258A264 (6) | |
Text
September 17, 2025 U.S. Nuclear Regulatory Commission Public Meeting Summary
Title:
Meeting with the Industry Steam Generator Task Force Meeting Identifier: 20251019 Date of Meeting: September 4, 2025 Location: Webinar Type of Meeting: Observation Meeting Purpose of the Meeting: The purpose of this meeting was for the U.S. Nuclear Regulatory Commission (NRC) staff to discuss steam generator (SG) issues with the industry Steam Generator Task Force (SGTF).
General Details: The industry SGTF met with NRC staff on September 4, 2025, by webinar.
The purpose of the meeting was to discuss a variety of SG issues. The NRC and industry slides are available in the Agencywide Documents Access and Management System (ADAMS)
Accession Nos. ML25240A903 and ML25244A003, respectively. This meeting was noticed as a public meeting and the agenda is available under ML25224A021.
LISTING OF ATTENDEES U.S. NRC MEETING WITH THE INDUSTRY STEAM GENERATOR TASK FORCE September 4, 2025 Participant Affiliation Participant Affiliation Isaac Anchondo-Lopez NRC Robert Himmelspach Tennessee Valley Authority Randall Atkinson EPRI Zachary Hollcraft Alba Energy Sasan Bakhtiari ANL Joel Jenkins NRC James Benson EPRI Andrew Johnson NRC Michael Benson NRC Craig Kelley Framatome Jana Bergman Curtiss Wright Sean Kil EPRI Cotasha Blackburn Southern Company Paul Klein NRC Steven Bloom NRC Greg Makar NRC Michael Bodak Constellation Jared Nadel NRC Jasmyn Bone Entergy Juan Perez Perez NRC Steven Boyles Constellation Paul Rittenhouse DEV Generation - 3 Scott Burnell NRC Phil Rush MPR Associates Brent Capell EPRI Timothy Saibena Vistra Corp.
Russ Cipolla Intertek Phillip Swearingen-Tomich Constellation Helen Cothron EPRI Leslie Terry NRC William Cullen EPRI Kester Thompson FPL Stephen Fluit BWXT Canada Ltd.
Tim Thulien Duke Michael Frotscher Entergy Luke Twarek Vistra Corp.
Veena Gubbi DEP Jonathan Zeitz DEP Rich Guill EPRI Summary of Presentations: Industry representatives made presentations on recently published Electric Power Research Institute (EPRI) reports, the status of revisions to industry guidelines, the industrys perspective on reporting the results of secondary-side activities to the NRC when primary-side inspections are not performed, and an update on the project to develop a wear scar sizing technique to be used on the outside of SG tubes during secondary-side activities.
The NRC staff presented an update on license renewal guidance, specifically changes in Revision 1 of the subsequent license renewal (SLR) guidance related to primary-side visual inspections recommended in the Steam Generators Aging Management Program (AMP),
XI.M19.
Additional details of the information exchanged during the meeting are provided below.
Recently published EPRI reports on the following topics were discussed:
Calculating anticipated leakage using an advanced probabilistic model under a range of accident conditions with measurable operational primary-to-secondary leakage occurring.
Closing two technical gaps associated with SG wet layup with no oxygen scavenger:
acceptable general corrosion rate of carbon and low alloy steel and susceptibility to crevice corrosion.
Adding additional operating experience to a report related to methods used for estimating tube support plate blockage.
Industry stated that revisions to the Steam Generator Management Program: Steam Generator Integrity Assessment Guideline (IAG) and the Steam Generator Management Program: In Situ Pressure Test Guidelines are in progress and a revision to the Steam Generator Management Program: Pressurized Water Reactor Steam Generator Examination Guidelines will be published in 2025.
Plants that have adopted Technical Specifications Task Force Traveler 577 (TSTF-577)1 or converted to Revision 5 of the Standard Technical Specifications (STS)2 may operate longer between primary-side inspections. Therefore, the industry discussed that some plants may perform secondary-side only activities when primary-side inspections are not performed.
The technical specifications (TS) for pressurized-water reactors require that a report be submitted to the NRC within 180 days after the initial entry into hot shutdown (MODE 4) 1 TSTF Response to NRC Questions on TSTF-577, Revision 0, Revised Frequencies for Steam Generator Tube Inspections, and Submittal of Revision 1 (ML21060B434).
2 NUREG-1430, Revision 5, Standard Technical Specifications Babcock and Wilcox Plants, dated September 2021 (ML21272A363 (Volume 1) and ML21272A370 (Volume 2).
NUREG-1431, Revision 5, Standard Technical Specifications Westinghouse Plants, dated September 2021 (ML21259A155 (Volume 1) and ML21259A159 (Volume 2).
NUREG-1432, Revision 5, Standard Technical Specifications Combustion Engineering Plants, dated September 2021 (ML21258A421 (Volume 1) and ML21258A424 (Volume 2)).
following completion of SG inspections (i.e., primary-side inspections) performed in accordance with the SG Program described in the plants TS (STS, Revision 5, Section 5.5.8). Therefore, the industry discussed how the NRC may be informed of the results of secondary-side activities when a SG tube inspection report is not required.
The industry discussed the following two recommendations: (1) add a new section (e.g.,
03.05) to NRC Inspection Procedure (IP) 71111.083 to include criteria related to secondary-side activities or results for NRC inspectors to promptly notify staff in the Office of Nuclear Reactor Regulation, and (2) revise the SG tube inspection report template in the IAG to include secondary-side activities performed since the last SG tube inspection report. The industry noted that while Section 03.04 of IP 71111.08 includes reporting of secondary-side activities, it applies only when scheduled primary-side inspection activities are performed.
The NRC staff stated that they would discuss the recommendation regarding changes to IP 71111.08 with their regional counterparts. The NRC staff also stated they did not expect to receive an additional report regarding secondary-side activities performed when primary-side inspections are not performed; however, if the secondary-side activity or inspection results could potentially impact SG tube integrity, the NRC staff would expect to be informed at the time of activity or inspection.
As noted above, plants that have adopted TSTF-577 or converted to Revision 5 of the STS may operate longer between primary-side inspections, therefore, some plants may perform secondary-side only activities when primary-side inspections are not performed. The industry discussed possible benefits of secondary-side activities, including proactive cleaning and maintenance, keeping the secondary-side clean from contaminants, and removing foreign objects (FOs). When FOs enter the secondary side, they can cause wear damage on the outside diameter (OD) of the SG tubes. Therefore, to eliminate the need to enter the primary-side, should tube wear from FOs be detected visually, the industry is developing a system capable of sizing wear scars from the OD of the SG tubes (i.e.,
secondary side) to determine whether the SG tubes with wear damage due to FOs may remain in service.
The industry researched over 30 non-destructive testing methods and selected an Eddy Current Array technique as the best method to characterize wear damage. Depth sizing curves will be developed based on the average signal amplitude compared to the true depth of each defect. The industry stated that the qualification process for the secondary-side wear damage sizing technique will fall under the Eddy Current Examination Technique Specification Sheet program.
The industry discussed the development of a delivery system for the secondary-side probe examination. Design considerations for the delivery system include tubesheet access, probe travel direction, probe positioning, and watertightness. The industry noted that the initial focus of the delivery system development is on the outermost periphery tubes and, if successful, then delivery system development will continue for tubes further into the bundle.
3 NRC Inspection Manual, Inspection Procedure 71111 Attachment 08, Inservice Inspection Activities (ML23226A223).
The NRC staff presented an update on license renewal guidance. No recent changes have been made to the initial license renewal guidance and changes to the SLR guidance were published on July 15, 2025 (GALL-SLR, Revision 1).
SLR applications for plants with thermally-treated Alloy 690 (A690TT) SG tubing and TS based on TSTF-577 (including conversion to Revision 5 of the STS) have proposed exceptions to the 72 Effective Full Power Months (EFPM) maximum interval between primary-side visual inspections recommended in the Steam Generators AMP in GALL-SLR, Revision 04. The exceptions requested a 96 EFPM maximum interval between primary-side visual inspections consistent with the increased maximum inspection interval for A690TT SG tubing in TSTF-577. GALL-SLR, Revision 1, updated the guidance related to primary-side visual inspections to reflect the 96 EFPM maximum inspection interval for units with A690TT SG tubing and TS based on TSTF-577.
Industry requested clarification on the GALL-SLR, Revision 1, changes related to the maximum inspection interval between primary-side visual inspections and the role of exceptions. In response, the NRC staff clarified that no action is required for the plants that had previously taken an exception because they have been approved for a maximum interval of 96 EFPM between primary-side visual inspections consistent with GALL-SLR, Revision 1. The NRC staff clarified that the exceptions previously proposed by plants with A690TT SG tubing and TS based on TSTF-577 do not apply to plants with A600TT SG tubing without cracking and with an operational assessment for four operating cycles because the maximum inspection intervals for these plants are not greater than 72 EFPM.
GALL-SLR, Revision 1, continues to reflect a 72 EFPM maximum interval between primary-side visual inspections consistent with the maximum inspection interval for plants with A600TT SG tubing and TS based on TSTF-577. Finally, the NRC staff clarified that exceptions are no longer needed for plants with A690TT SG tubing and A600TT SG tubing and TS based on TSTF-577 in the SLR application process.
If you have any questions regarding this meeting summary, please feel free to contact Leslie Terry by phone at 301-415-1167, or by email at Leslie.Terry@nrc.gov.
Attachments:
- 1. Meeting Notice:
- 2. NRC Slides:
- 3. Industry Slides:
- 4. Package:
ML25258A263 4 NUREG-2191, Revision 0, Generic Aging Lessons Learned for Subsequent License Renewal (GALL-SLR) Report, dated July 2017 (ML17187A031 (Volume 1) and ML17187A204 (Volume 2)).
NUREG-2192, Revision 0, Standard Review Plan for Review of Subsequent License Renewal Applications for Nuclear Power Plants, dated July 2017 (ML17188A158).
Package: ML25258A263 Meeting Summary: ML25258A264 Meeting Notice: ML25224A021 NRC Slides: ML25240A903 Industry Slides: ML25244A003 OFFICE NRR/DNRL/NCSG NRR/DNRL/NRLB/LA NRR/DNRL/NCSG/BC NAME LTerry SGreen SBloom DATE 9/15/2025 9/16/2025 9/17/2025