ML21271A100

Notice of Enforcement Discretion (NOED) for Seabrook Station, Unit No. 1

ML21271A100
Person / Time
Site:	Seabrook
Issue date:	09/28/2021
From:	Dan Collins NRC/RGN-I/DORS
To:	Coffey R Florida Power & Light Co
References
EA-21-138, EPID L-2021-LLA-0168
Download: ML21271A100 (5)

Text

September 28, 2021 EA-21-138 Mr. Robert Coffey Executive Vice President, Nuclear Division and Chief Nuclear Officer Florida Power & Light Company 700 Universe Blvd.

Mail Stop: EX/JB Juno Beach, FL 33408

SUBJECT:

NOTICE OF ENFORCEMENT DISCRETION (NOED) FOR SEABROOK STATION, UNIT NO. 1 (EPID: L-2021-LLA-0168)

Dear Mr. Coffey:

By letter (Agencywide Documents Access and Management System (ADAMS) Accession No. ML21268A003) dated September 25, 2021, NextEra Energy Seabrook, LLC (NextEra, the licensee) requested the U.S. Nuclear Regulatory Commission (NRC) to exercise discretion to not enforce compliance with the actions required by Seabrook Station, Unit No. 1 (Seabrook),

Technical Specifications (TS) Limiting Condition for Operation (LCO) 3.7.4 - Service Water System/Ultimate Heat Sink.

This letter documents information previously discussed with the NRC in telephone conferences held on September 23, 2021, at 2:00 p.m. and 6:30 p.m. Eastern Standard Time (EST). The principal NRC staff members who participated in the telephone conferences are listed in the Enclosure. The NRC staff determined that the information contained in your letter requesting the NOED was consistent with your oral request.

The NRC first became aware of the potential for this NOED request on September 23, 2021, at approximately 6:00 a.m. EST through communication with the Seabrook Senior Resident Inspector. The licensee requested that an NOED be granted pursuant to the NRCs policy regarding exercise of discretion for an operating power reactor, set out in the NRC Enforcement Manual, Appendix F, Notices of Enforcement Discretion, and the NOED be effective for five days past the LCO 3.7.4, Action b expiration date of September 24, 2021 (i.e., until 4:56 a.m.

EST on Wednesday, September 29, 2021). This letter documents the event and our telephone conversation on September 23, 2021, when we orally granted this NOED request.

R. Coffey 2 On the morning of September 17, 2021, the Unit 1 B service water cooling tower fan experienced a failure while in service. At 4:56 a.m. EST, the licensee declared one cooling tower service water loop inoperable and entered TS LCO 3.7.4, Action b. Investigation found the fan driveshaft had sheared and the gearbox was leaking oil and both items were replaced.

During post-maintenance testing on Wednesday, September 22, the newly installed gearbox exhibited elevated vibrations. The licensee determined that the elevated vibrations on the newly installed gearbox were indications of an unsatisfactory gear mesh tolerance within the gearbox.

The licensee determined that the repair methods available to the station to correct the condition would exceed the TS LCO completion time and initiated the NOED process with the NRC.

During the teleconference held on September 23, 2021, the licensee requested enforcement discretion for the brief period of time that was required to process an emergency TS License Amendment Request (LAR) under the provisions of Title 10 of the Code of Federal Regulations (10 CFR) 50.91(a)(5). This TS LAR is expected to extend the TS LCO 3.7.4 Action b.

completion time to provide the necessary time to restore the service water cooling tower Unit 1 B fan to an operable status. Without this enforcement discretion, Unit 1 was required to be in MODE 3 by 10:56 a.m. EST on September 24, 2021, and Mode 5 by 4:56 p.m. EST on September 25, 2021. During internal NRC discussions, the Office of Nuclear Reactor Regulation, Division of Operating Reactor Licensing expressed confidence in completing the LAR review based on the straightforward nature of the change and the very low risk increase associated with the additional fan unavailability.

The licensee indicated that the calculated increase in Unit 1 incremental conditional core damage probability (ICCDP), using the zero-maintenance probability model, for the requested five day enforcement discretion period was 3.97E-9. The licensee also indicated that the increase in Unit 1 incremental conditional large early release probability (ICLERP) was 1.37E-12. These values were less than the 5E-7 ICCDP and 5E-8 ICLERP guidance thresholds specified in the NRC Enforcement Manual, Appendix F.

During the requested period of enforcement discretion, the licensee proposed to implement compensatory risk management measures to reduce the likelihood of risk significant initiating events and protect risk significant equipment and actions. These measures included but were not limited to:

• Protecting risk significant systems and areas;

• Restricting maintenance and surveillance activities;

• Monitoring weather and grid conditions; and

• Briefing operators on plant recovery procedures for a degraded ultimate heat sink The licensees Plant Health Committee (PORC) approved submission of the NOED request on September 23, 2021, prior to the verbal request for an NOED.

Based on the NRC staffs evaluation of the licensees request, the staff determined that granting this NOED was consistent with the NRCs Enforcement Policy and staff guidance. The NOED request met the criteria specified in Sections 2.2 and 2.5 of Appendix F, Notices of Enforcement Discretion, of the NRCs Enforcement Manual. Specifically, the NRC determined that it was appropriate to exercise discretion for the brief period of time required for the licensee and the NRC staff to process an emergency TS LAR under the provisions of 10 CFR 50.91(a)(5) and avoid an unnecessary shutdown of a reactor without a corresponding benefit to public health and safety or the environment. Therefore, as communicated orally to the

R. Coffey 3 licensee at approximately 7:30 p.m. EST on September 23, 2021, the NRC exercised discretion to not enforce compliance with TS LCO 3.7.4, Action b. for a period of five days, which would require a shutdown by 10:56 a.m. EST on September 24, 2021.

In accordance with the granted NOED, NextEra submitted the emergent TS LAR on September 25 (ADAMS Accession No. ML21268A004) to modify TS 3.7.4 Action b by extending the completion time on a one-time basis for a Service Water system cooling water cell from seven to 16 days to allow entry into Mode 5 during a planned refueling outage, which is scheduled to begin early October 2021. The NRC staff noted, subsequent to its verbal approval for enforcement discretion, that the condition causing the need for this NOED was corrected and Seabrook exited from TS LCO 3.7.4 at 4:47 a.m. EST on September 26, 2021. As a result, this NOED terminated at 4:47 a.m. EST on September 26, 2021, within the period of the enforcement discretion.

As stated in the NRC Enforcement Policy, enforcement action may be taken to the extent that violations were involved for the root cause that led to the noncompliance for which this NOED was necessary.

In accordance with 10 CFR 2.390 of the NRCs Rules of Practice, a copy of this letter will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRC's document system (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).

Sincerely, Digitally signed by Daniel Daniel S. S. Collins Date: 2021.09.28 Collins 15:14:54 -04'00' Daniel S. Collins, Director Division of Operating Reactor Safety Docket No. 05000443 License No. NPF-86

Enclosures:

1. List of Key NRC Personnel

2. Seabrook Station Notice of Enforcement Request cc w/ encl: Distribution via LISTSERV

ML21271A100 X Non-Sensitive X Publicly Available X SUNSI Review Sensitive Non-Publicly Available OFFICE RI/DORS RI/DORS NAME BBickett EMiller CCarusone DCollins DATE 9/28 /21 9/28/21 9/28/21 9/28/21 LIST OF KEY NRC PERSONNEL NRC REGION I R. Felts, Director, Division of Operating Reactor Safety (DORS)

P. Krohn, Deputy Director, DORS B. Bickett, Branch Chief, DORS, Projects Branch 3 C. Newport, Seabrook Senior Resident Inspector, DORS, Projects Branch 3 F. Arner, Senior Reactor Analyst, DORS D. Werkheiser, Senior Reactor Analyst, DORS W. Cook, Senior Reactor Analyst, DORS Office of Nuclear Reactor Regulation C. Carusone, Deputy Director, Division of Operating Reactor Licensing (DORL)

J. Danna, Branch Chief, DORL, Plant Licensing Branch I J. Poole, Project Manager, DORL, Plant Licensing Branch I E. Miller, Senior Project Manager, DORL, Plant Licensing Branch II-1 M. Montecalvo, Senior Reactor Analyst, Division of Risk Assessment, PRA Licensing Oversight Branch B. Wittick, Branch Chief, Division of Safety Systems, Containment and Plant Systems Branch R. Vettori, Fire Protection Engineer, Division of Risk Assessment, PRA Licensing Branch B B. Lee, Safety and Plant Systems Engineer, Division of Safety Systems, Containment and Plant Systems Branch Enclosure 1