ML21182A220
| ML21182A220 | |
| Person / Time | |
|---|---|
| Site: | Robinson  |
| Issue date: | 07/09/2021 |
| From: | Klos L Plant Licensing Branch II |
| To: | Kapopoulos E Duke Energy Progress |
| Klos L | |
| References | |
| EPID L-2021-LRM-0060 | |
| Download: ML21182A220 (4) | |
Text
July 9, 2021 LICENSEE:
Duke Energy Progress, LLC FACILITY:
H. B. Robinson Steam Electric Plant, Unit 2
SUBJECT:
SUMMARY
OF JUNE 24, 2021, MEETING WITH DUKE ENERGY PROGRESS, LLC, REGARDING A PROPOSED AMENDMENT CONCERNING TSTF-577, REVISED FREQUENCIES FOR STEAM GENERATOR FREQUENCIES FOR STEAM GENERATOR TUBE INSPECTIONS FOR THE H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT 2 (EPID L-2021-LRM-0060)
On June 24, 2021, an observation public meeting was held between the U.S. Nuclear Regulatory Commission (NRC) and Duke Energy Progress, LLC (Duke Energy), the licensee of the H. B. Robinson Steam Electric Plant (Robinson) via teleconference due the COVID-19 Public Health Emergency. The purpose of the meeting was to discuss a future amendment concerning Technical Specification Task Force (TSTF) Traveler TSTF-577, Revision 1, Revised Frequencies for Steam Generator Tube Inspections. The meeting notice and agenda are available in the Agencywide Documents Access and Management System (ADAMS)
Accession No. ML21161A190. A list of attendees is provided as Enclosure 1.
Robinson has three Westinghouse Electric Company (Westinghouse) Model 44F steam generators (SGs) with thermally treated Alloy 600 tubes. The licensee presented information (see ADAMS Accession No. ML21174A321) which summarized the licensees upcoming proposed license amendment request (LAR) anticipated for submittal in August 2021. The licensee also presented the proposed LARs technical basis. The licensee intends to request a one-time 72-month inspection interval beginning in late December 2020 without having performed a 100-percent enhanced probe inspection per the TSTF-577 provisions. The licensee presented a technical justification for the variation in terms of the existing degradation mechanisms in the Robinson SGs, the scope of recent inspections, a relatively low hot-leg temperature, the operating fleet experience with the same tube material at other locations, management of loose parts and foreign objects, the amount of secondary side deposits, enhanced inspection of tubes with potentially high residual stress, and the operational assessment (OA) supporting three operating cycles for existing degradation mechanisms before the next inspection.
As an opening statement, the NRC branch chief for the Corrosion and Steam Generator Branch stated that the NRC staff is not expecting to be receiving multiple LARs for exceptions to the recently issued TSTF-577. The NRC staff recognized, however, that since Robinson is the only unit with thermally treated Alloy 600TT tubing that is on a 24-month refueling cycle and that the NRC staff had planned to have plant-specific discussions with the licensee. During the meeting, the NRC staff and licensee discussed several topics including the following:
- 1. The NRC asked the licensee to discuss the scope of the most recent SG inspections that occurred in the Fall of 2020, including the consideration of the extent of inspection with enhanced probes. The NRC stated that the staffs position on enhanced inspection that is contained in TSTF-577 was not known at the time of the Robinson inspection. The licensee responded that the inspection scope was established 12 months prior to the inspection, and at that time the NRC staffs position on enhanced probe inspections was not known.
- 2. In response to a question from the NRC staff, the licensee stated that if the proposed LAR is approved they intend to perform a 100-percent enhanced probe inspection in the future. This would permit future 72-month inspection intervals without a LAR if the other provisions of TSTF-577 are met and it is supported by the unit-specific OA.
- 3. The NRC staff asked if the licensee intended to include stress-corrosion cracking as a potential degradation mechanism in its OA to support the proposed LAR. The NRC staff stated its expectation that stress-corrosion cracking would be addressed despite the plant operating at a relatively low hot-leg temperature. This expectation is based on the operating experience with thermally treated Alloy 600 tubing and the potential for growth of cracks that may have gone undetected in the most recent inspection. The licensee replied that they would consider the NRC staffs input. The NRC staff also stated its expectation that the OA would provide a detailed analysis for foreign objects.
Duke Energy stated they will consider and evaluate the questions, and the technical and licensing comments presented by the NRC staff and, as appropriate, include adequate and sufficient material for the NRC staff to complete the technical review of the future amendment.
The NRC staff agreed to provide any additional feedback on the presentation to the NRC project manager by July 2, 2021.
Members of the public were not in attendance. Public Meeting Feedback forms were not received.
Please direct any inquiries to me at 301-415-5136, or John.Klos@nrc.gov.
/RA/
John Klos, Project Manager Plant Licensing Branch LPL2-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-261
Enclosure:
List of Attendees cc: Listserv
Meeting Notice: ML21161A190 Meeting Summary: ML21182A220 Presentation: ML21174A321 OFFICE NRR/DORL/LPL2-2/PM NRR/DORL/LPL2-2/LA NRR/DORL/LPL2-2/BC NRR/DORL/LPL/2-2/PM NAME John Klos Rhonda Butler Mike Mahoney (A) BC John Klos DATE 6/28/2021 7/7/21 7/7/2021 7/9/2021
Enclosure LIST OF ATTENDEES JUNE 24, 2021 MEETING WITH DUKE ENERGY PROGRESS, LLC REGARDING A PROPOSED AMENDMENT CONCERNING TSTF-577, REVISED FREQUENCIES FOR STEAM GENERATOR FREQUENCIES FOR STEAM GENERATOR TUBE INSPECTIONS FOR THE H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT 2 (EPID L-2021-LRM-0060)
ATTENDEE REPRESENTING John Klos NRC Nate Jordan NRC Paul Klein NRC Andrew Johnson NRC Gregory Makar NRC Leslie Terry NRC Clinton Ashley NRC Steve Bloom NRC Christian Scott NRC Gabe Lentchner NRC Art Zaremba Duke Energy Jordan Vaughn Duke Energy Etienne Fonteneau Duke Energy Dan Mayes Duke Energy Doug Coughman Duke Energy Scott Linger Duke Energy Brad Carpenter Duke Energy (Westinghouse)