RA-25-0064, Proposed Alternative for Inservice Testing Interval Code of Record
| ML25206A082 | |
| Person / Time | |
|---|---|
| Site: | Catawba  |
| Issue date: | 07/24/2025 |
| From: | Ellis K Duke Energy Corp |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| RA-25-0064 | |
| Download: ML25206A082 (1) | |
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DUKE ENERGY
Serial: RA-25-0064 July 24, 2025 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Catawba Nuclear Station, Unit Nos. 1 and 2 Renewed Facility Operating License Nos. NPF-35 and NPF-52 Docket Nos. 50-413 and 50-414 KevinM. Ellis General Manager Nuclear Regulatory Affairs, Policy &
Emergency Preparedness Duke Energy 13225 Hagers Ferry Rd., MG011 E Huntersville, NC 28078 843-951-1329 Kevin.Ellis@duke-energy.com 10 CFR 50.55a
SUBJECT:
Proposed Alternative for lnservice Testing Interval Code of Record Ladies and Gentlemen:
Pursuant to 10 CFR 50.55a(z)(1), Duke Energy Carolinas, LLC (Duke Energy) is proposing an lnservice Testing (1ST) alternative for the Catawba Nuclear Station (CNS), Unit Nos. 1 and 2.
Specifically, this request is to utilize the 2020 Edition of the American Society of Mechanical Engineers (ASME) Operation and Maintenance (OM) Code in lieu of the 2022 Edition that would be required by 10 CFR 50.55a(f)(4)(ii). This proposed alternative applies to the next CNS Code of Record Interval, which includes the Fifth and Sixth 1ST Intervals.
The proposed alternative is described in Enclosure 1.
Duke Energy requests approval of this proposed alternative prior to the start of the Fifth 1ST Interval, scheduled to start on August 19, 2026. If you have additional questions, please contact Ryan Treadway, Director - Nuclear Fleet Licensing, at 980-373-5873.
Kevin M.
General Manager-Nuclear Regulatory Affairs, Policy & Emergency Preparedness
Enclosures:
- 1. Proposed Alternative for lnservice Testing Interval Code of Record
U.S. Nuclear Regulatory Commission RA-25-0064 Page 2 cc:
USNRC Region II Regional Administrator USNRC Senior Resident Inspector for CNS USNRC NRR Project Manager for CNS
RA-25-0064 Proposed Alternative for Inservice Testing Interval Code of Record 5 Pages Follow
RA-25-0064 Page 1 of 5 1.0 ASME CODE COMPONENTS AFFECTED All components tested in the Inservice Testing (IST) Program for Catawba Nuclear Station (CNS) Unit Nos. 1 and 2.
2.0 APPLICABLE CODE EDITION AND ADDENDA American Society of Mechanical Engineers (ASME) Operation and Maintenance (OM)
Code, 2020 Edition. (Reference 8.1)
American Society of Mechanical Engineers (ASME) Operation and Maintenance (OM)
Code, 2022 Edition. (Reference 8.2) 3.0 APPLICABLE CODE REQUIREMENT OR APPLICABLE REGULATORY REQUIREMENT Information from 10 CFR 50.55a Paragraph (f)(4)(ii) states the following:
Applicable IST Code: Successive code of record intervals. Inservice tests to verify operational readiness of pumps and valves, whose function is required for safety, conducted during successive code of record intervals must comply with the requirements of the latest edition and addenda of the ASME OM Code incorporated by reference in paragraph (a)(1)(iv) of this section no more than 18 months before the start of the code of record interval (or the optional ASME Code Cases listed in NRC Regulatory Guide 1.147 or NRC Regulatory Guide 1.192 as incorporated by reference in paragraphs (a)(3)(ii) and (iii) of this section, respectively), subject to the conditions listed in paragraph (b) of this section.
Paragraph (b)(3) states the following:
Conditions on ASME OM Code. As used in this section, references to the ASME OM Code are to the ASME OM Code, Subsections ISTA, ISTB, ISTC, ISTD, ISTE, and ISTF; Mandatory Appendices I, II, III, IV, and V; and Nonmandatory Appendices A through H and J through M, in the 1995 Edition through the latest edition and addenda of the ASME OM Code incorporated by reference in paragraph (a)(1)(iv) of this section.
Mandatory appendices must be used if required by the OM Code; nonmandatory appendices are approved for use by the NRC but need not be used. When implementing the ASME OM Code, conditions are applicable only as specified in the following paragraphs:
RA-25-0064 Page 2 of 5 4.0 REASON FOR REQUEST Catawba Nuclear Station is performing an update to the IST Program as required by 10 CFR 50.55a(f)(4)(ii).
10 CFR 50.55a(f)(4)(ii) requires (emphasis added):
Applicable IST Code: Successive code of record intervals. Inservice tests to verify operational readiness of pumps and valves, whose function is required for safety, conducted during successive code of record intervals must comply with the requirements of the latest edition and addenda of the ASME OM Code incorporated by reference in paragraph (a)(1)(iv) of this section no more than 18 months before the start of the code of record interval (or the optional ASME Code Cases listed in NRC Regulatory Guide 1.147 or NRC Regulatory Guide 1.192 as incorporated by reference in paragraphs (a)(3)(ii) and (iii) of this section, respectively), subject to the conditions listed in paragraph (b) of this section.
The Catawba Nuclear Station Fifth IST Interval was originally scheduled to start August 19, 2025. To allow sufficient time to implement the significant changes required to update to the OM Code-2020 Edition, Catawba also extended the Fourth IST Interval by one year, as allowed by ASME OM Code-2004/2006, ISTA-3120(d). This results in a new scheduled Fifth IST Interval start date of August 19, 2026.
However, the latest change to 10 CFR 50.55a to incorporate a new ASME Code edition was published in the Federal Register on August 30, 2024 (Reference 8.3), with an effective date of September 30, 2024. This update incorporates by reference the OM Code-2022 Edition in 10 CFR 50.55a(a)(1)(iv). This published/effective date was earlier than the NRC originally scheduled and requires Catawba Nuclear Station to either a) fully implement the requirements of OM Code 2020 Edition on or before March 30, 2026 due to the 18-month requirement OR b) fully implement the requirements of OM Code 2022 Edition by August 19, 2026 in accordance with 10 CFR 50.55a(f)(4)(ii).
In addition to the fact that the interval update process is already underway, utilizing the OM Code-2020 Edition, Catawba Nuclear Station would also benefit from maintaining consistency with the McGuire Nuclear Station, which also recently updated to the OM Code-2020 Edition. While not identical, Duke Energys Catawba Nuclear Station and McGuire Nuclear Station share many design characteristics; they are both Westinghouse 4 loop Ice Condenser plants with smaller containments and many near-identical safety systems. As such, the IST Programs are very similar, and it would be beneficial for the purpose of sharing resources and information across sites if both sites are licensed to the same edition of the OM Code.
5.0 PROPOSED ALTERNATIVE AND BASIS FOR USE Pursuant to 10 CFR 50.55a, Codes and Standards, paragraph (z)(1), Catawba Nuclear Station proposes the following as an alternative to the requirements of 10 CFR 50.55a(f)(4)(ii): that Catawba Nuclear Station will update the IST Program to the Rules of the 2020 Edition of ASME OM Code, rather than the 2022 Edition of the ASME OM Code, while still maintaining the IST Fifth Interval start date of August 19, 2026.
RA-25-0064 Page 3 of 5 This is being requested to maintain Catawba and McGuire on the same edition of the ASME OM Code. This will allow Duke Energy to maintain a higher level of standardization between the McGuire and Catawba IST Programs.
The interval update project for both stations has already been budgeted and scheduled.
Update contracts were awarded, and work has commenced with tasks completed for both sites based on the 2020 Edition of ASME OM Code. Due to the required number of changes needed, Catawba has extended the Fourth IST Interval by one year, as allowed by ASME OM Code-2004/2006, ISTA-3120(d) to August 19, 2026. Updating Catawba to the 2022 Edition of the OM Code would require additional effort that was not planned or budgeted when the update project began. It will also require Duke Energy to maintain IST programs for the two similarly designed plants with slightly different code requirements. As Catawba and McGuire share Operating Experience and resources between sites, utilizing a common set of code requirements would minimize the risk of errors during program development and implementation.
Although the OM Code 2022 Edition includes changes from the 2020 Edition, both editions continue to ensure an acceptable level of quality and safety. Furthermore, the changes did not address any deficiencies in the Code that adversely impacted safety.
The most recent update to 10 CFR 50.55a (Reference 8.3) by the NRC does not require facilities utilizing earlier editions and addenda to implement any new provisions from the 2022 Edition. A thorough comparison of the 2020 and 2022 Editions revealed some minor changes around pump vibration and check valve trending, as well as MOV Diagnostic analysis, but most of the changes were to provide clarification or to incorporate previous NRC conditions directly into the code. There were no changes that were necessary to ensure acceptable quality and safety standards, nor were any revisions made to correct deficiencies present in the 2020 Edition.
Duke Energy believes that updating the Catawba IST Programs to the 2020 Edition to be consistent with the McGuire IST Program, which entered its new interval in March 2025, will improve the level of quality and safety at both stations. This enables utilizing knowledge from both sites for IST activities, including program development, planning, scheduling, testing, and assessment, thereby providing Duke Energy with extensive experience to reference.
Based on the above, Duke Energy requests authorization for the proposed alternative pursuant to 10 CFR 50.55a(z)(1) on the basis that it provides an acceptable level of quality and safety.
RA-25-0064 Page 4 of 5 6.0 DURATION OF PROPOSED ALTERNATIVE This proposed alternative will be implemented during the upcoming Catawba Code of Record Interval for inservice testing of pumps and valves. The Code of Record Interval includes both the Fifth and Sixth IST intervals as defined in 10 CFR 50.55a(y)(2):
(y) Definitions. As used in this section:
Code of record interval means the period of time between the code of record updates required by paragraphs (f)(4) and (g)(4) of this section for the inservice examination and test programs and inservice inspection programs, respectively.
(1) For licensees with codes of record prior to ASME BPV Code,Section XI, 2017 Edition, and OM Code, 2017 Edition, as incorporated by reference in paragraph (a) of this section, the code of record interval is the same as the inservice inspection interval or inservice examination and test interval.
(2) For licensees with codes of record of ASME BPV Code,Section XI, 2017 Edition and OM Code, 2017 Edition, or later, as incorporated by reference in paragraph (a) of this section, the code of record interval is two consecutive inservice inspection or inservice examination and test intervals.
7.0 PRECEDENTS A search for precedents related to updating the IST Program's code of record in accordance with 10 CFR 50.55a(f)(4)(ii) was conducted, and none were identified.
However, the following precedents provide a similar basis for updating a code of record for Inservice Inspection (ISI) Programs in accordance with 10 CFR 50.55a(g)(4)(ii).
7.1 Michael T. Markley to Thomas D. Ray dated August 21, 2020,
Subject:
McGuire Nuclear Station, Unit 1 - Relief Request RA-20-0031, Delay to Update the Code of Record for Inservice Inspection (EPID L-2019-LLR-0119), ADAMS Accession Number (ML20230A205).
7.2 Robert J. Pascarelli to ANO Site Vice President dated June 11, 2019,
Subject:
Arkansas Nuclear One, Unit 2 - Request for Alternative AN02-ISl-021 to Permit Continued Application of the 2007 Edition Through the 2008 Addenda of the ASME CODE (EPID L-2018-LLR-0122), ADAMS Accession Number (ML19156A400).
7.3 Robert J. Pascarelli to David A Heacock dated April 29, 2013,
Subject:
Surry Power Station, Unit Nos 1 and 2 - Relief From the Requirements of the ASME Section XI Code S1-15-ISI-01 & S2-15-ISI-01 Regarding Use of ASME Section XI 2004 Edition (TAC NOS. ME8774 AND ME8775), ADAMS Accession Number (ML13100A049).
RA-25-0064 Page 5 of 5
8.0 REFERENCES
8.1 American Society of Mechanical Engineers (ASME) Operation and Maintenance (OM) Code, 2020 Edition.
8.2 American Society of Mechanical Engineers (ASME) Operation and Maintenance (OM) Code, 2022 Edition.
8.3 Federal Register, 89 FR 70467, dated August 30, 2024.