ML24088A101

Summary of March 6, 2024, Public Meeting with NSPM Regarding Planned LAR to Modify Technical Specifications Definitions and Incorporate Plant-Specific Methods for Response Time Testing for Prairie Island Nuclear Plant, Units 1 & 2

ML24088A101
Person / Time
Site:	Prairie Island
Issue date:	03/29/2024
From:	Ballard B Plant Licensing Branch III
To:	Northern States Power Co
Ballard B
References
EPID L-2024-LRM-0034
Download: ML24088A101 (1)

Text

March 29, 2024

LICENSEE: Northern States Power Company

FACILITY: Prairie Island Nuclear Generating Plant, Units 1 and 2

SUMMARY

OF MARCH 6, 2024, PUBLIC MEETING WITH NORTHERN STATES POWER COMPANY REGARDING PLANNED LICENSE AMENDMENT REQUEST TO MODIFY TECHNICAL SPECIFICATIONS DEFINITIONS AND INCORPORATE PLANT-SPECIFIC METHODS FOR RESPONSE TIME TESTING (EPID L-2024-LRM-0034)

On March 6, 2024, a public meeting via webinar was held between the U.S. Nuclear Regulatory Commission (NRC) and representatives of No rthern States Power Company, a Minnesota corporation (NSPM, the licensee), doing business as Xcel Energy. The purpose of the meeting was to discuss a planned license amendment request (LAR) to revise the technical specifications (TS) definitions and incorporate plant-specific methods for response time testing at Prairie Island Nuclear Generating Plant, Units 1 and 2 (Prairie Island). The meeting notice and agenda, dated February 26, 2024, are available in the Agencywide Documents Access and Management System (ADAMS) Accession No. ML24057A036. The presentation material used by the licensee during the meeting is available in ADAMS Accession No. ML24059A404. A list of attendees is enclosed.

During the meeting, NSPM presented information regarding the planned LAR. The licensee discussed the following topics as part of its presentation:

Purpose

The licensee discussed the purpose of the LAR, which revises the TS definition of REACTOR TRIP SYSTEM (RTS) RESPONSE TIME by implementing a plant-specific methodology for allocating response times, and includes a request to approve a proposed plant-specific methodology for allocating response times. The planned LAR would also revise TS Table 3.3.1-1 to apply TS surveillance requirement (SR) 3.3.1.16 to those RTS functions that have an assumed time delay in the accident analyses.

Background

The licensee discussed NSPMs evaluation of the adopting of Technical Specifications Tast Force Traveler TSTF-569, Revise Response Time Testing Definition, Revision 2 (ML19176A034) for Prairie Island. Adoption of TSTF-569 permits licenses, in lieu of measurement, to verify the RTS response times of certain component types by using the methodology contained in TSTF-569 and WCAP-14036-P-A, Elimination of Periodic Protection Channel Response Time Tests, Revision 1 (ML100050325). NSPM determined TSTF-569 does not apply to the Prairie Island Process Protection System (PPS) because the Prairie Island PPS was not among the systems listed in WCAP-14036-P-A and the

associated NRC safety evaluation. Because th e TSTF is not applicable to Prairie Island PPS, NSPM is proposing a plant-specific method for allocating response times. The licensee stated the LAR will propose a method similar to TSTF-569 for allocating response times, but the scope of the LAR will vary from the TSTF due to differences in the Prairie Island TS.

Proposed licensing action

Consistent with TSTF-569 and NUREG-1431, Standard Technical Specifications -

Westinghouse Plants, (ML21259A155), the licensee proposes to revise the definition of REACTOR TRIP SYSTEM (RTS) RESPONSE TIME in TS 1.1, Definitions, to add the following to the current definition:

In lieu of measurement, response time may be verified for selected components provided that the components and methodology for verification have been previously reviewed and approved by the NRC, or the components have been evaluated in accordance with an NRC approved methodology.

Additionally, the licensee proposes to revise the applicability of SR 3.3.1.16, Verify RTS RESPONSE TIME is within limits, such that the SR is no longer applicable to the following two functions in Table 3.3.1-1:

- 3.b. Power Range Neutron Flux Rate - High Negative Rate

- 5. Source Range Neutron Flux

The licensee broadly discussed their basis for removing SR 3.3.1.16 from these two functions in their presentation. The applicability of SR 3.3.1.16 is also revised such that the SR would be applicable to the following four functions in Table 3.3.1-1:

- 8.a. Pressurizer Pressure - Low

- 8.b. Pressurizer Pressure - High

- 10. Reactor Coolant Flow - Low

- 13. SG [Steam Generator] Water Level - Low Low

Additionally, the licensee discussed their proposed site-specific methodology for allocating response times to RTS components subject to response time testing at Prairie Island. The licensee stated the methodology would be modeled on TSTF-569, Methodology 2, but will account for the specific PPS components instal led at Prairie Island. The licensee discussed the applicability of Methodology 2 by comparing previously approved equipment in WCAP-14036-P-A with the installed PPS equipment at Prairie Island.

Schedule

The licensee discussed its planned submittal schedule, requested approval date, and revised TS implementation period. NSPM plans to submit the LAR in April 2024, and request NRC approval 12 months from acceptance. NSPM stated their goal is to implement the LAR with the 2025 Unit 2 refueling outage.

The NRC staff provided feedback on the planned s ubmittal and asked questions throughout the presentation. The NRC staff asked the licensee to discuss the following items in more detail during the meeting:

For the functions in Table 3.3.1-1 that are currently not subject to SR 3.3.1.16 but are proposed to be revised to have response time testing with the LAR, please discuss if these functions are currently tested, even though they are not required by TS.

The licensee explained that two of the functions, Pressurizer Pressure - Low and Reactor Coolant Flow - Low, are currently tested. Testing for those two functions is conducted to validate time delay assumptions in the accident analysis. Response time testing is being added to the other two functions, Pressurizer Pressure - High and SG Water Level - Low Low, because there is a response time assumption in the USAR.

TSTF-569 and the STS already include the proposed change to the REACTOR TRIP SYSTEM (RTS) RESPONSE TIME definition. The NRC staff asked if site-specific justification would be provided in the LAR for the addition of this text to the Prairie Island TS?

The licensee clarified that they will be providing justification for the addition of this text.

In their presentation, the licensee provided a broad discussion on their basis for removing SR 3.3.1.16 from two functions in Table 3.3.1-1. The NRC staff asked if the LAR would provide a more detailed discussion, and can you discuss what changed such that testing is no longer needed for these functions?

The licensee stated a detailed discussion on the basis for the proposed removal of testing from the two functions in Table 3.3.1-1 would be provided with the LAR. The licensee stated they did not have the information available at the time of the meeting to fully address the staffs question on why testing is no longer needed, but stated there were changes to the accident analyses when accident analysis functions were transferred from NSPM to Westinghouse. The licensee also stated it could be from their Improved STS conversion.

The licensee stated they would need to research why these functions currently have response time testing in the TS even though the functions do not have time delay assumptions in the accident analyses. The NRC st aff stated the information may be helpful and reduce questions if it were detailed in the LAR.

In their presentation, the licensee stated they intended to use Methodology 2 from TSTF-569 to model their proposed site-specific methodology. The NRC staff asked if the LAR would provide basis and discussion on the licensees decision to use this methodology as the model for their proposed methodology.

As described in the TSTF-569, Methodology 2 is explicitly applicable to the six listed systems. The licensee stated that their equipment is similar to one of the listed systems in TSTF-569, but since their equipment is not listed, a new methodology needs to be developed based on Methodology 2. The licensee intends to provide supporting details on the similarities to support using Methodology 2 as a model to develop their site-specific methodology.

No regulatory decisions were made during the meeting. No members of the public were in attendance. No comments or questions from the public were received during the meeting.

Public Meeting Feedback forms were not received.

Please direct any inquiries regarding this meeting summary to me at 301-415-0680 or Brent.Ballard@nrc.gov.

/RA/

Brent Ballard, Project Manager Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Docket Nos. 50-282 and 50-306

Enclosure:

List of Attendees

cc: Listserv

LIST OF ATTENDEES

MARCH 6, 2024, PUBLIC MEETING WITH NORTHERN STATES POWER COMPANY

PRAIRIE ISLAND NUCLEAR GENERATING PLANT, UNITS 1 AND 2

PROPOSED LICENSE AMENDMENT REQUEST

TO MODIFY TECHNICAL SPECIFICATIONS DEFINITIONS AND

INCORPORATE PLANT SPECIFIC METHODS FOR RESPONSE TIME TESTING

Name Organization Brent Ballard U.S. Nuclear Regulatory Commission (NRC)

Santosh Bhatt NRC Calvin Cheung NRC John Parillo NRC Luis Cruz Rosado NRC Fanta Sacko NRC Tarico Sweat NRC Daniel Tesar NRC Hannah Freeman Northern States Power Company (NSPM)

Jeffrey Kivi NSPM Jim Madden NSPM Michael Miller NSPM George Huber, Jr. Sargent & Lundy Christopher Mundt Sargent & Lundy

Enclosure

ML24088A101 OFFICE NRR/DORL/LPL3/PM NRR/DORL/LPL3/LA NRR/DORL/LPL3/BC NRR/DORL/LPL3/PM NAME BBallard SRohrer JWhited BBallard DATE 3/28/2024 3/28/2024 3/28/2024 3/29/2024