L-PI-24-009, Response to Request for Additional Information Prairie Island Nuclear Generating Plant, Unit 2, Alternative RR-09 Safety Injection System and Volume Control System Category C Check Valve Quarterly Testing

Response to Request for Additional Information Prairie Island Nuclear Generating Plant, Unit 2, Alternative RR-09 Safety Injection System and Volume Control System Category C Check Valve Quarterly Testing

ML24044A103
Person / Time
Site:	Prairie Island
Issue date:	02/13/2024
From:	Borgen T Northern States Power Company, Minnesota, Xcel Energy
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
L-PI-24-009, EPID L-2024-LLR-0015
Download: ML24044A103 (5)

Text

1717 Wakonade Drive Welch, MN 55089 February 13, 2024 L-PI-24-009 10 CFR 50.55a ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Prairie Island Nuclear Generating Plant, Unit 2 Docket No. 50-306 Renewed Facility Operating License No. DPR-60 Response to Request for Additional Information RE: Prairie Island Nuclear Generating Plant, Unit 2, Alternative RR-09 Safety Injection System and Volume Control System Category C Check Valve Quarterly Testing (EPID: L-2024-LLR-0015)

References:

1) L-PI-24-008, NSPM Web-based Relief Request, Prairie Island Nuclear Generating Plant Unit 2 10 CFR 50.55a Inservice Testing Proposed Alternative RR-09, submission date February 11, 2024 (ADAMS Accession No. ML24042A001)

2) Email from the NRC to NSPM, Prairie Island Unit 2 - Final RAI for Alternative RR-09 (EPID NUMBER L-2024-LLR-0015), dated February 12, 2024 In Reference 1, Northern States Power Company, a Minnesota corporation, doing business as Xcel Energy (hereafter NSPM), submitted 10 CFR 50.55a Request RR-09 proposing an alternative to American Society of Mechanical Engineers (ASME) Operation and Maintenance of Nuclear Power Plants (OM Code), Requirement ISTC-3510, ISTC-3522, ISTC-3570, for Prairie Island Nuclear Generating Plant (PINGP) Unit 2. In Reference 2, the NRC requested additional information needed for the NRC staff to complete its review. The enclosure to this letter provides NSPMs response to the NRC Request for Additional Information.

Summary of Commitments This letter makes no new commitments and no revisions to existing commitments.

fl Xcel Energy

Document Control Desk L-Pl-24-009 Page 2 Please contact Mr. Jeff Kivi at (612) 330-5788 or Jeffrey.L.Kivi@xcelenergy.com if there are any questions or if additional information is needed.

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Timothy P. Borgen Plant Manager, Prairie Island Nuclear Generating Plant Northern States Power Company - Minnesota Enclosure cc:

Administrator, Region Ill, USNRC

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Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC

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L-PI-24-009 NSPM Enclosure Page 1 of 3 Response to Request for Additional Information RE:

Prairie Island Nuclear Generating Plant, Unit 2, Alternative RR-09 Related to Pressure Isolation Valve Monitoring and Testing

1.0 BACKGROUND

In Reference 1, Northern States Power Company, a Minnesota corporation, doing business as Xcel Energy (hereafter NSPM), submitted 10 CFR 50.55a Request RR-09 proposing an alternative to American Society of Mechanical Engineers (ASME) Operation and Maintenance of Nuclear Power Plants (OM Code), Requirement ISTC-3510, ISTC-3522, ISTC-3570, for Prairie Island Nuclear Generating Plant (PINGP) Unit 2. In Reference 2, the NRC requested additional information needed for the NRC staff to complete its review. NSPMs response to the NRC Request for Additional Information (RAI) is provided below.

2.0 NRC REQUEST FOR ADDITIONAL INFORMATION AND NSPM RESPONSE By electronic submission dated February 11, 2024 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML24042A001), Northern States Power Company (NSPM, the licensee), a Minnesota corporation, doing business as Xcel Energy, submitted Alternative Request RR-09 for the Inservice Testing (IST) Program at Prairie Island Nuclear Generating Plant, Unit 2. Pursuant to Title 10 of Code of Federal Regulations (10 CFR) Section 50.55a(z)(2), the proposed alternative requests to defer quarterly testing of certain Category C check valves in the Safety Injection system and Volume Control system until the next refueling outage or the end of the Fifth 10-Year IST Program interval, currently scheduled to end on December 20, 2024, whichever comes first.

The U.S. Nuclear Regulatory Commission (NRC) staff has determined that additional information is required to complete its review of the request.

The NRC regulations in 10 CFR 50.55a(z) specify the following:

Alternatives to the requirements of paragraphs (b) through (h) of this section or portions thereof may be used when authorized by the Director, Office of Nuclear Reactor Regulation. A proposed alternative must be submitted and authorized prior to implementation. The applicant or licensee must demonstrate that:

(1) Acceptable level of quality and safety. The proposed alternative would provide an acceptable level of quality and safety; or (2) Hardship without a compensating increase in quality and safety. Compliance with the specified requirements of this section would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.

L-PI-24-009 NSPM Enclosure Page 2 of 3

RAI-1

The proposed duration of Alternative Request RR-09 is from approval until the next Unit 2 refueling outage or the end of the 5th interval whichever comes first. The request states the Fifth 10-Year IST Program interval is scheduled to end on December 20, 2024. Prairie Islands next refueling outage (RFO) is expected to occur in the fall of 2025. In light of these date differences, the NRC staff requests the following information:

a. Is NSPM considering an extension of the Fifth 10-Year IST Program interval per American Society of Mechanical Engineers (ASME) Operation and Maintenance of Nuclear Power Plants (OM) Code, Subsection ISTA, paragraph ISTA-3120?

b. If NSPM is planning to extend the Fifth 10-Year IST Program interval, please confirm NSPM meets the ASME OM Code requirements of paragraph ISTA-3120 to extend the interval.

c. Based on the current IST Program Plan, the fall 2025 RFO will take place during the Sixth 10-Year IST Program interval. The NRC process does not authorize alternatives for future 10-Year IST Program intervals because each request must be re-evaluated for acceptability with respect to the ASME OM Code edition required for the future IST program. In isolated situations, a licensee has justified a request to extend the duration of a proposed alternative for a short duration into the next IST Program interval. See NRC SE dated July 27, 2023, for Comanche Peak Alternative Request RV-1 (ML23198A321). If NSPM is planning for the request to extend beyond the end of the Fifth 10-Year IST Program interval, the licensee will need to justify that extension in Alternative Request RR-09.

d. If the Fifth 10-Year IST Program interval is extended by the application of ISTA-3120, the alternative, if authorized, would remain applicable until the end of the extended Fifth 10-Year IST Program interval. If the Fifth 10-Year IST Program interval is extended, please confirm NSPM will conduct the tests of the subject check valves the next opportunity that plant conditions support testing.

RAI-2

Per 10 CFR 50.55a(z), the NRC staff may only authorize an alternative request for future activities. For the requirement of ISTC-5221(a)(3) applicable to check valve 2VC-8-3, please confirm if the alternative is requested for subsequent testing requirements.

NSPM Response to RAI-1

a.

Yes. NSPM plans to extend the Fifth 10-Year IST Program interval to December 20, 2025, per ISTA-3120.

b.

Yes. NSPM meets the requirements of ISTA-3120 to extend the Fifth 10-Year IST Program interval.

L-PI-24-009 NSPM Enclosure Page 3 of 3

c.

No. NSPM is not requesting that the proposed alternative extend beyond the end of the extended Fifth 10-Year IST Program interval.

d.

Yes. NSPM will conduct the tests of the subject check valves the next time plant conditions support conducting the tests.

NSPM Response to RAI-2 No. NSPM is not requesting an alternative to the requirements of ISTC-5221(a)(3) for subsequent tests of valve 2VC-8-3.

3.0 REFERENCES

1.

L-PI-24-008, Prairie Island Nuclear Generating Plant Unit 2 10 CFR 50.55a Inservice Testing Proposed Alternative RR-09, submission date February 11, 2024 (ADAMS Accession No. ML24042A001)

2.

Email from the NRC to NSPM, Prairie Island Unit 2 - Final RAI for Alternative RR-09 (EPID NUMBER L-2024-LLR-0015), dated February 12, 2024