ML22136A109

Proposed Alternative Request RP-2 Regarding the Inservice Testing of Certain Pumps

ML22136A109
Person / Time
Site:	Davis Besse
Issue date:	05/24/2022
From:	Blake Purnell Plant Licensing Branch III
To:	Tony Brown Energy Harbor Nuclear Corp
Purnell B
References
EPID L-2021-LLR-0071
Download: ML22136A109 (7)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON , D.C. 20555-0001 May 24, 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-2 REGARDING THE INSERVICE TESTING OF CERTAIN PUMPS (EPID L-2021-LLR-0071)

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-2 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 September 20, 2021, letter also submitted three other requests; however, this letter only pertains to alternative request RP-2.

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-2 would allow the licensee to use digital instruments for certain comprehensive pump testing that do not meet the selection criterion in subparagraph ISTB-3510(b)(2) of the 2017 Edition of the ASME OM Code, as incorporated by reference in 10 CFR 50.55a, for the fifth 10-year IST interval at Davis-Besse.

The regulations in 10 CFR 50.55a(z)(1) 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 the proposed alternative provides an acceptable level of quality and safety.

The NRC staff has reviewed alternative request RP-2 and concludes, as set forth in the enclosed safety evaluation, that the licensee has adequately addressed the regulatory requirements set forth in 10 CFR 50.55a(z)(1). Therefore, the NRC staff authorizes the use of proposed alternative request RP-2 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 Nancy L. Nancy L. Salgado Date: 2022.05.24 Salgado 15:30:34 -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-2 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-2 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-2.

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-1 would allow the licensee to use digital instruments for certain comprehensive pump testing that do not meet the selection criterion in subparagraph ISTB-3510(b)(2) of the 2017 Edition of the ASME OM Code, as incorporated by reference in 10 CFR 50.55a, for the fifth 10-year IST interval at Davis-Besse. Pursuant to 10 CFR 50.55a(z)(1), the licensee requested the proposed alternative on the basis that it provides an acceptable 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]] (ML14003A266), the 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 10 CFR 50.55a(a)(1)(iv), to the extent practical within the limitations of design, geometry, and materials of construction of the components.

Enclosure

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 Component ID Pump Description ASME Code OM Group Class P14-1 Auxiliary Feedwater Pump Class 3 Group B P14-2 Auxiliary Feedwater Pump Class 3 Group B P56-1 Containment Spray Pump Class 2 Group B P56-2 Containment Spray Pump Class 2 Group B P42-1 Decay Heat Removal Pump Class 2 Group A P42-2 Decay Heat Removal Pump Class 2 Group A 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 ASME OM Code, as incorporated by reference in 10 CFR 50.55a with conditions. Subparagraph ISTB-3510(b)(2) of the ASME OM Code states: Digital instruments shall be selected such that the reference value does not exceed 90% of the calibrated range of the instrument.

Reason for Request

The licensee stated, in part, that:

Plant process computer points may be used as digital instrumentation for inservice testing of pumps. The computer points may be used in lieu of the associated analog indicators in order to meet the ASME OM Code instrument accuracy requirements. In addition to using computer points, temporary digital instruments are also used as measuring and test equipment for pump testing.

In some cases, the reference value could exceed 90 percent of the digital instruments calibrated range during pump testing in accordance with Subsection ISTB of the 2017 Edition of the OM Code (for pumps P14-1, P14-2, P56-1, P56-2, P42-1, and P42-2).

Proposed Alternative The licensee proposes to select digital instruments to verify the required action levels in subsection ISTB of the ASME OM Code such that the reference value shall not exceed 94 percent of the calibrated range for comprehensive pump testing. 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 licensee proposed an alternative to the digital instrumentation requirements in subparagraph ISTB-3510(b)(2) of the ASME OM Code for the comprehensive testing of the pumps listed in SE section 3.1. The licensee stated, in part, that:

Plant process computer points or temporary digital instruments may be used for OM Code Subsection ISTB pump testing. The computer points use permanent plant instrumentation as input, and by design, the ranges are selected to account for all expected operating and testing conditions. Surveillance tests are written such that the temporary instrumentation is not over-ranged. In addition, digital instrumentation is significantly less susceptible to damage from over-ranging, and the digital instrument is accurate throughout its full calibrated range.

Subparagraph ISTB-3510(b)(2) of the ASME OM Code requires that reference values of digital instruments do not exceed 90 percent of the calibrated range of the instrument. Subparagraph ISTB-3510(b)(2) applies to instruments used to measure flow and differential pressure, but it does not apply to instruments used to measure vibration. The applicable acceptance criteria for the comprehensive testing of the subject pumps are listed in table ISTB-5121-1, Centrifugal Pump Test Acceptance Criteria, of the ASME OM Code. This table states, in part, that the maximum acceptable values for both the measured flow and differential pressure is 106 percent of the reference value.

For the proposed alternative to subparagraph ISTB-3510(b)(2) of the ASME OM Code, the licensee would select digital instruments for comprehensive pump testing such that the reference value shall not exceed 94 percent of the calibrated range. The licensee stated that this ensures that when the digital instrument is reading the maximum action level of 106 percent of the reference value during pump testing, the reading is within the calibrated range of the instrument.

The NRC staff determined that the proposed alternative for selecting digital instruments for the comprehensive pump testing is acceptable because the maximum acceptable values (i.e.,

106 percent of the reference value) for both the measured flow and differential pressure would be within the calibrated range of the instruments. Therefore, the NRC staff finds that the proposed alternative provides an acceptable level of quality and safety for the comprehensive testing of the pumps listed in SE section 3.1.

4.0 CONCLUSION

As set forth above, the NRC staff finds that proposed alternative for the selection of digital instruments for the comprehensive testing of the pumps listed in SE section 3.1 will provide an acceptable level of quality and safety. Accordingly, the NRC staff concludes that the licensee has adequately addressed the regulatory requirements set forth in 10 CFR 50.55a(z)(1).

Therefore, the NRC staff authorizes the use of proposed alternative request RP-2 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 Contributor: Gurjendra Bedi, NRR/DEX/EMIB Date: May 24, 2022

ML22136A109 OFFICE NRR/DORL/LPL3/PM NRR/DORL/LPL3/LA NRR/DEX/EMIB/BC(A)

NAME BPurnell SRohrer ITseng DATE 5/16/22 5/16/22 4/22/22 OFFICE NRR/DORL/LPL3/BC NAME NSalgado DATE 5/24/22