ML22118B038

Proposed Alternative Request RP-4 Regarding the Inservice Testing of High-Pressure Injection Pumps

ML22118B038
Person / Time
Site:	Davis Besse
Issue date:	05/05/2022
From:	Scott Wall Plant Licensing Branch III
To:	Tony Brown Energy Harbor Nuclear Corp
Purnell B
References
EPID L-2021-LLR-0073
Download: ML22118B038 (7)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON , D.C. 20555-0001 May 5, 2022 Mr. Terry J. Brown Site Vice President Energy Harbor Nuclear Corp.

Mail Stop P-DB-3080 5501 North State Route 2 Oak Harbor, OH 43449-9760

SUBJECT:

DAVIS-BESSE NUCLEAR POWER STATION, UNIT NO. 1 PROPOSED ALTERNATIVE REQUEST RP-4 REGARDING THE INSERVICE TESTING OF HIGH-PRESSURE INJECTION PUMPS (EPID L-2021-LLR-0073)

Dear Mr. Brown:

By letter dated September 20, 2021 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML21263A193), Energy Harbor Nuclear Corp. (the licensee) submitted request RP-4 in accordance with paragraph 50.55a(z)(2) of Title 10 of the Code of Federal Regulations (10 CFR) for a proposed alternative to certain requirements of 10 CFR 50.55a, Codes and standards, for Davis-Besse Nuclear Power Station, Unit No. 1 (Davis-Besse). The September 20, 2021, letter also submitted three other requests; however, this letter only pertains to alternative request RP-4.

The American Society of Mechanical Engineers (ASME), Operation and Maintenance of Nuclear Power Plants, Division 1, Section IST (OM Code), as incorporated by reference in 10 CFR 50.55a, specifies requirements for the inservice testing (IST) of nuclear power plant components. Proposed alternative request RP-4 would allow the licensee to perform comprehensive testing of the Davis-Besse high-pressure injection pumps each refueling outage, instead of biennially, for the fifth 10-year IST interval.

The regulations in 10 CFR 50.55a(z)(2) states, in part, that alternatives to the requirements in paragraphs (b) through (h) of 10 CFR 50.55a may be authorized by the U.S. Nuclear Regulatory Commission (NRC) if the licensee demonstrates that complying with the specific ASME OM Code requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. The NRC staff has reviewed alternative request RP-4 and concludes, as set forth in the enclosed safety evaluations, that the licensee has adequately addressed the regulatory requirements set forth in 10 CFR 50.55a(z)(2). Therefore, the NRC staff authorizes the use of proposed alternative request RP-4 at Davis-Besse for the fifth 10-year IST interval, which is scheduled to begin on September 21, 2022, and end on September 20, 2032.

All other ASME OM Code requirements for which an alternative was not specifically requested and authorized remain applicable.

T. Brown If you have any questions, please contact Blake Purnell at 301-415-1380 or via e-mail at Blake.Purnell@nrc.gov.

Sincerely, Digitally signed by Scott P. Scott P. Wall Date: 2022.05.05 Wall 14:09:27 -04'00' Nancy L. Salgado, Chief Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-346

Enclosure:

Safety Evaluation cc: Listserv

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION PROPOSED ALTERNATIVE REQUEST RP-4 ENERGY HARBOR NUCLEAR CORP.

ENERGY HARBOR NUCLEAR GENERATION LLC DAVIS-BESSE NUCLEAR POWER STATION, UNIT NO. 1 DOCKET NO. 50-346

1.0 INTRODUCTION

By letter dated September 20, 2021 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML21263A193), Energy Harbor Nuclear Corp. (the licensee) submitted alternative request RP-4 in accordance with paragraph 50.55a(z)(1) of Title 10 of the Code of Federal Regulations (10 CFR) for a proposed alternative to certain requirements of 10 CFR 50.55a, Codes and standards, for Davis-Besse Nuclear Power Station, Unit No. 1 (Davis-Besse). The letter also included three other requests; however, this safety evaluation (SE) is only for alternative request RP-4.

The American Society of Mechanical Engineers (ASME), Operation and Maintenance of Nuclear Power Plants, Division 1, Section IST (OM Code), as incorporated by reference in 10 CFR 50.55a, specifies requirements for the inservice testing (IST) of nuclear power plant components. Proposed alternative request RP-4 would allow the licensee to perform comprehensive testing of the Davis-Besse high-pressure injection (HPI) pumps each refueling outage, instead of biennially, for the fifth 10-year IST interval. Pursuant to 10 CFR 50.55a(z)(2),

the licensee requested the proposed alternative on the basis that complying with the specific ASME OM Code requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.

By [[letter::L-14-120, Firstenergy Nuclear Operating Company (FENOC) Seismic Hazard and Screening Report (CEUS Sites), Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Recommendation 2.1 of the Near-Term Task Force (NTTF) Review of In|letter dated March 31, 2014]] (ML14030A574), the U.S. Nuclear Regulatory Commission (NRC) staff authorized a similar alternative request for the fourth 10-year IST interval at Davis-Besse.

2.0 REGULATORY EVALUATION

The regulations in 10 CFR 50.55a(f)(4) state, in part, that throughout the service life of a boiling or pressurized water-cooled nuclear power facility, pumps and valves that are within the scope of the ASME OM Code must meet the IST requirements (except design and access provisions) set forth in the ASME OM Code and addenda that become effective subsequent to editions and addenda specified in 10 CFR 50.55a(f)(2) and (3) and that are incorporated by reference in Enclosure

10 CFR 50.55a(a)(1)(iv), to the extent practical within the limitations of design, geometry, and materials of construction of the components.

The regulations in 10 CFR 50.55a(z) state, in part, that alternatives to the requirements in paragraphs (b) through (h) of 10 CFR 50.55a may be authorized by the NRC if the licensee demonstrates that: (1) the proposed alternative provides an acceptable level of quality and safety, or (2) compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.

3.0 TECHNICAL EVALUATION

3.1 Licensees Request ASME Code Components Affected The ASME Code Class 2, HPI pump Nos. P58-1 and P58-2.

Applicable Code Edition and Requirements The applicable ASME OM Code edition for the fifth 10-year IST program interval at Davis-Besse is the 2017 Edition of the ASME OM Code, as incorporated by reference in 10 CFR 50.55a with conditions. Table ISTB-3400-1 of the ASME OM Code requires Group A and Group B pump tests to be performed quarterly and a comprehensive pump test to be performed biennially.

Article ISTB-2000 of the ASME OM Code defines the following:

Group A pumps are pumps that are operated continuously or routinely during normal operation, cold shutdown, or refueling operations.

Group B pumps are pumps in standby systems that are not operated routinely except for testing.

Reason for Request

The application states, in part, that:

To achieve the necessary flow rate, without creating low temperature overpressure concerns, the high pressure injection pumps are lined up to discharge into the reactor coolant system with the reactor head removed and with water in the refueling canal. These plant conditions are established only during an outage in which a refueling occurs and are not typically established during a maintenance outage.

The licensee stated that it can normally comply with the ASME OM Code requirement to perform the comprehensive HPI pump tests biennially since the plant is on a 24-month fuel cycle. However, the licensee stated that if the plant experiences maintenance shutdowns, the added time between refueling outages could jeopardize compliance with this testing requirement. In addition, the licensee stated that removal of the reactor head solely to perform the comprehensive pump test is a hardship since it would substantially increase the scope and duration of a maintenance shutdown and result in associated radiation exposure.

Proposed Alternative The licensee stated that comprehensive testing of the HPI pumps will be performed each refueling outage instead of biennially. For testing purposes, the classification of these pumps will be changed from Group B to Group A so that the ASME OM Code vibration test requirements (subparagraphs ISTB-5121(d) and (e)) and associated acceptance criteria (table ISTB-5151-1) would apply during the quarterly pump test.

The licensee requested NRC authorization to use this proposed alternative for the duration of the fifth 10-year IST program interval at Davis-Besse, which is scheduled to begin on September 21, 2022, and end on September 20, 2032.

3.2 NRC Staff Evaluation The HPI pumps inject water into the reactor coolant system to mitigate the consequences of a loss-of-coolant accident. In alternative request RP-4, the licensee proposed to perform comprehensive testing of the HPI pump Nos. P58-1 and P58-2 each refueling outage, instead of biennially, for the fifth 10-Year IST interval at Davis-Besse. In addition, the licensee would reclassify the HPI pumps as Group A pumps for testing purposes, so that the ASME OM Code vibration test requirements and associated acceptance criteria would apply during the quarterly pump test. Therefore, the NRC staff finds that the proposed alternative would provide reasonable assurance that these HPI pumps will be operationally ready to perform their safety functions.

The licensee stated that the conditions required for the comprehensive testing of the HPI pumps at Davis-Besse are normally not achieved outside of a refueling outage. If the plant experiences a maintenance shutdown, the licensee stated that the added time between refueling outages could jeopardize compliance with this testing requirement. The NRC staff finds that the licensee has demonstrated that compliance with the specified requirements in the ASME OM Code for biennial testing of these pumps would result in hardship or unusual difficulty because performance of this testing during a maintenance shutdown would substantially increase the scope and duration of a maintenance shutdown and could lead to increased radiation exposure to plant workers.

Based on the above, the NRC staff finds that the licensee has demonstrated that compliance with the specified requirements in the ASME OM Code for biennial testing of these pumps would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety in accordance with 10 CFR 50.55a(z)(2).

4.0 CONCLUSION

As set forth above, the NRC staff finds that alternative request RP-4 will provide reasonable assurance that the subject HPI pumps will be operationally ready to perform their safety functions at Davis-Besse. The NRC staff also finds that the licensee has demonstrated that compliance with the specified requirements in the ASME OM Code for biennial testing of these two HPI pumps would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety in accordance with 10 CFR 50.55a(z)(2). Accordingly, the NRC staff concludes that the licensee has adequately addressed the regulatory requirements set forth in 10 CFR 50.55a(z)(2). Therefore, the NRC staff authorizes the use of proposed alternative request RP-4 at Davis-Besse for the fifth 10-year IST interval, which is scheduled to begin on September 21, 2022, and end on September 20, 2032.

All other ASME OM Code requirements for which an alternative was not specifically requested and authorized remain applicable.

Principal Contributors: Tristan Villarreal, NRR/DEX/EMIB Thomas Scarbrough, NRR/DEX/EMIB Date: May 5, 2022

ML22118B038 OFFICE NRR/DORL/LPL3/PM NRR/DORL/LPL3/LA NRR/DEX/EMIB/BC(A)

NAME BPurnell SRohrer ITseng DATE 5/3/22 5/3/22 4/19/22 OFFICE NRR/DORL/LPL3/BC NAME NSalgado (SWall for)

DATE 5/5/22