ML22068A025
| ML22068A025 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 03/15/2022 |
| From: | Markley M NRC/NRR/DORL/LPL2-1 |
| To: | Snider S Duke Energy Carolinas |
| Williams, S. | |
| References | |
| EPID L-2021-LLR-0054 | |
| Download: ML22068A025 (9) | |
Text
March 15, 2022 Mr. Steven M. Snider Vice President, Oconee Nuclear Station Duke Energy Carolinas, LLC 7800 Rochester Highway Seneca, SC 29672-0752
SUBJECT:
OCONEE NUCLEAR STATION, UNITS 1, 2, AND 3 - RE: CODE CASE OMN 28, ALTERNATIVE VALVE POSITION VERIFICATION APPROACH TO SATISFY ISTC-3700 FOR VALVES NOT SUSCEPTIBLE TO STEM-DISK SEPARATION (EPID L-2021-LLR-0054)
Dear Mr. Snider:
By letter dated July 29, 2021, as supplemented by letters dated August 19, 2021, and November 9, 2021, Duke Energy Carolinas, LLC (Duke Energy, the licensee) submitted a request to the U.S. Nuclear Regulatory Commission (NRC) for the use of an alternative to certain American Society of Mechanical Engineers (ASME) Operation and Maintenance of Nuclear Power Plants (OM Code) requirements at Oconee Nuclear Station (ONS, Oconee),
Units 1, 2, and 3, during the sixth 10-year inservice testing (IST) program interval.
Pursuant to the requirements of Title 10 of the Code of Federal Regulations (10 CFR) 50.55a Codes and Standards, specifically 10 CFR 50.55a(z)(1), the licensee requested to implement ASME OM Code Case OMN-28, Alternative Valve Position Verification Approach to Satisfy ISTC-3700 for Valves Not Susceptible to Stem-Disk Separation, for specific identified valves with position indication requirements on the basis that the alternative provides an acceptable level of quality and safety.
The NRC staff has reviewed the subject request, 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 proposed alternative in relief request ON-RPI-OMN-28 for the sixth 10-year IST program interval for ONS Units 1, 2, and 3, that begins on July 1, 2022.
All other ASME OM Code requirements for which relief or an alternative was not specifically requested and approved remain applicable.
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001
S. Snider If you have any questions, please email Shawn.Williams@nrc.gov.
Sincerely, Michael T. Markley, Chief Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-269, 50-270, and 50-287
Enclosure:
Safety Evaluation cc: Listserv Michael T.
Markley Digitally signed by Michael T. Markley Date: 2022.03.15 12:48:51 -04'00'
Enclosure SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION PROPOSED ALTERNATIVE REQUEST ON-RPI-OMN-28 RELATED TO THE INSERVICE TESTING PROGRAM SIXTH 10-YEAR INTERVAL DUKE ENERGY CAROLINAS, LLC (DUKE ENERGY)
OCONEE NUCLEAR STATION, UNIT NOS. 1, 2, AND 3 DOCKET NOS. 50-269, 50-270, AND 50-287
1.0 INTRODUCTION
By letter dated July 29, 2021 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML21210A341), as supplemented by letters dated August 19, 2021 (ADAMS Accession No. ML21231A069) and November 9, 2021 (ADAMS Accession No. ML21313A028), Duke Energy Carolinas, LLC (Duke Energy, the licensee) submitted to the U.S.
Nuclear Regulatory Commission (NRC) proposed alternative request ON-RPI-OMN-28 regarding in lieu of certain inservice testing (IST) requirements of the American Society of Mechanical Engineers (ASME) Operation and Maintenance of Nuclear Power Plants, Division 1, OM Code: Section IST (OM Code) for the IST programs at Oconee Nuclear Station (ONS, Oconee), Units 1, 2, and 3, during the sixth 10-year IST program interval.
Specifically, pursuant to subparagraph (1) in paragraph (z), Alternatives to codes and standards requirements, of Section 55a, Codes and standards, in Part 50, Domestic Licensing of Production and Utilization Facilities, in Title 10, Energy, of the Code of Federal Regulations (10 CFR 50.55a(z)(1)), the licensee requested to implement ASME OM Code Case OMN-28 (Code Case OMN-28), Alternative Valve Position Verification Approach to Satisfy ISTC-3700 for Valves Not Susceptible to Stem-Disk Separation, for certain valves at Oconee on the basis that the alternative provides an acceptable level of quality and safety.
2.0 REGULATORY EVALUATION
The NRC regulations in 10 CFR 50.55a(f)(4), Inservice testing standards requirement for operating plants, state the following:
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 inservice test 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 paragraphs (f)(2) and (3) of this section and that are incorporated by reference in paragraph (a)(1)(iv) of this section, to the extent practical within the limitations of design, geometry, and materials of construction of the components. The inservice test requirements for pumps and valves that are within the scope of the ASME OM Code but are not classified as ASME BPV Code Class 1, Class 2, or Class 3 may be satisfied as an augmented IST program in accordance with paragraph (f)(6)(ii) of this section without requesting relief under paragraph (f)(5) of this section or alternatives under paragraph (z) of this section. This use of an augmented IST program may be acceptable provided the basis for deviations from the ASME OM Code, as incorporated by reference in this section, demonstrates an acceptable level of quality and safety, or that implementing the Code provisions would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety, where documented and available for NRC review.
The NRC regulations in 10 CFR 50.55a(b)(3)(xi), OM condition: Valve Position Indication, state the following:
When implementing paragraph ISTC-3700, Position Verification Testing, in the ASME OM Code, 2012 Edition through the latest edition and addenda of the ASME OM Code incorporated by reference in paragraph (a)(1)(iv) of this section, licensees shall verify that valve operation is accurately indicated by supplementing valve position indicating lights with other indications, such as flow meters or other suitable instrumentation to provide assurance of proper obturator position for valves with remote position indication within the scope of Subsection ISTC including its mandatory appendices and their verification methods and frequencies.
In proposing alternatives, a licensee must demonstrate that the proposed alternatives provide an acceptable level of quality and safety (10 CFR 50.55a(z)(1)) or compliance would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety (10 CFR 50.55a(z)(2)).
3.0 TECHNICAL EVALUATION
3.1 Applicable ASME OM Code The applicable ASME OM Code for the IST Programs at ONS Units 1, 2, and 3, for the sixth 10-year IST program interval, is the 2017 Edition, which is currently scheduled to commence on July 1, 2022, and end on June 30, 2032.
As provided in its submittal dated August 19, 2021, the IST requirements of the ASME OM Code, as incorporated by reference in 10 CFR 50.55a related to this alternative request are as follows:
ASME OM Code, Subsection ISTC, Inservice Testing of Valves in Light-Water Reactor Nuclear Power Plants, Subsection ISTC, paragraph ISTC-3700, Position Verification Testing, states the following:
Valves with remote position indicators shall be observed locally at least once every 2 yr to verify that valve operation is accurately indicated. Where practicable, this local observation should be supplemented by other indications such as use of flow meters or other suitable instrumentation to verify obturator position. These observations need not be concurrent.
Where local observation is not possible, other indications shall be used for verification of valve operation. Position verification for active MOVs [motor-operated valves] shall be tested in accordance with Mandatory Appendix III of this Division.
In addition, the NRC regulations in 10 CFR 50.55a(b)(3)(xi) specify supplemental requirements for the implementation of the ASME OM Code, Subsection ISTC, paragraph ISTC-3700, for licensees applying the 2012 Edition and later editions of the ASME OM Code.
Mandatory Appendix III, Preservice and Inservice Testing of Active Electric Motor-Operated Valve Assemblies in Water-Cooled Reactor Nuclear Power Plants, paragraph III-3300, Inservice Test, subparagraph (e) states that remote position indication shall be verified locally during inservice testing or maintenance activities.
3.2 ASME Code Components Affected
In its letter dated November 9, 2021, the licensee provided the following list of valves that are applicable to this request:
Building Spray (1BS-1, 1BS-2, 1BS-3, 1BS-4, 2BS-1, 2BS-2, 2BS-3, 2BS-4, 3BS-1, 3BS-2, 3BS-3, and 3BS-4)
Condensate (1C-156, 1C-158, 1C-160, 1C-391, 1C-903, 1C-904, 1C-906, 1C-907, 2C-156, 2C-158, 2C-160, 2C-391, 2C-903, 2C-904, 2C-906, 2C-907, 3C-156, 3C-158, 3C-160, 3C-391, 3C-903, 3C-904, 3C-906, and 3C-907)
Core Flood System (1CF-1, 1CF-2, 1CF-3, 1CF-4, 1CF-5, 1CF-6, 2CF-1, 2CF-2, 2CF-3, 2CF-4, 2CF-5, 2CF-6, 3CF-1, 3CF-2, 3CF-3, 3CF-4, 3CF-5, and 3CF-6)
Essential Siphon Vacuum (1ESV-28, 1ESV-29, 2ESV-28, 2ESV-29, 3ESV-28, and 3ESV-29)
Feedwater (1FWD-32, 1FWD-35, 1FWD-41, 1FWD-44, 1FWD-103, 1FWD-104, 1FWD-106, 1FWD-108, 1FWD-315, 1FWD-316, 1FWD-347, 1FWD-368, 1FWD-369, 1FWD-372, 1FWD-382, 2FWD-32, 2FWD-35, 2FWD-41, 2FWD-44, 2FWD-103, 2FWD-104, 2FWD-106, 2FWD-108, 2FWD-315, 2FWD-316, 2FWD-347, 2FWD-368, 2FWD-369, 2FWD-372, 2FWD-382, 3FWD-32, 3FWD-35, 3FWD-41, 3FWD-44, 3FWD-103, 3FWD-104, 3FWD-106, 3FWD-108, 3FWD-315, 3FWD-316, 3FWD-347, 3FWD-368, 3FWD-369, 3FWD-372, and 3FWD-382)
Gaseous Waste Disposal (1GWD-17, 2GWD-17, and 3GWD-17)
High Pressure Injection (1HP-23, 1HP-24, 1HP-25, 1HP-26, 1HP-27, 1HP-98, 1HP-115, 1HP-139, 1HP-140, 1HP-398, 1HP-409, 1HP-410, 1HP-939, 1HP-940, 2HP-23, 2HP-24, 2HP-25, 2HP-26, 2HP-27, 2HP-98, 2HP-115, 2HP-139, 2HP-140, 2HP-398, 2HP-409, 2HP-410, 2HP-939, 2HP-940, 3HP-23, 3HP-24, 3HP-25, 3HP-26, 3HP-27, 3HP-98, 3HP-115, 3HP-139, 3HP-140, 3HP-398, 3HP-409, 3HP-410, 3HP-939, and 3HP-940)
Low Pressure Injection (1LP-1, 1LP-2, 1LP-3, 1LP-5, 1LP-6, 1LP-7, 1LP-8, 1LP-9, 1LP-10, 1LP-11, 1LP-12, 1LP-13, 1LP-14, 1LP-15, 1LP-16, 1LP-17, 1LP-18, 1LP-19, 1LP-20, 1LP-21, 1LP-22, 1LP-69, 1LP-103, 1LP-104, 1LP-105, 2LP-1, 2LP-2, 2LP-3, 2LP-5, 2LP-6, 2LP-7, 2LP-8, 2LP-9, 2LP-10, 2LP-11, 2LP-12, 2LP-13, 2LP-14, 2LP-15, 2LP-16, 2LP-17, 2LP-18, 2LP-19, 2LP-20, 2LP-21, 2LP-22, 2LP-69, 2LP-103, 2LP-104, 3LP-1, 3LP-2, 3LP-3, 3LP-5, 3LP-6, 3LP-7, 3LP-8, 3LP-9, 3LP-10, 3LP-12, 3LP-14, 3LP-15, 3LP-16, 3LP-17, 3LP-18, 3LP-19, 3LP-20, 3LP-21, 3LP-22, 3LP-92, 3LP-93, 3LP-103, and 3LP-104)
Low Pressure Service Water (LPSW-1, LPSW-2, LPSW-3, 1LPSW-4, 1LPSW-5, 1LPSW-6, 1LPSW-15, 1LPSW-16, 1LPSW-18, 1LPSW-19, 1LPSW-21, 1LPSW-22, 1LPSW-24, 1LPSW-139, 1LPSW-1121, 1LPSW-1122, 1LPSW-1123, 1LPSW-1124, 1LPSW-1150, 1LPSW-1151, 2LPSW-4, 2LPSW-5, 2LPSW-6, 2LPSW-15, 2LPSW-16, 2LPSW-18, 2LPSW-19, 2LPSW-21, 2LPSW-22, 2LPSW-24, 2LPSW-139, 2LPSW-1121, 2LPSW-1122, 2LPSW-1123, 2LPSW-1124, 2LPSW1150, 2LPSW-1151, 3LPSW-4, 3LPSW-5, 3LPSW-6, 3LPSW-15, 3LPSW-16, 3LPSW-18, 3LPSW-19, 3LPSW-21, 3LPSW-22, 3LPSW-24, 3LPSW-120, 3LPSW-123, 3LPSW-139, 3LPSW-1121, 3LPSW-1122, 3LPSW-1123, 3LPSW-1124, 3LPSW-1150, and 3LPSW-1151)
Main Steam (1MS-17, 1MS-24, 1MS-26, 1MS-33, 1MS-35, 1MS-36, 1MS-76, 1MS-79, 1MS-82, 1MS-84, 1MS-93, 1MS-102, 1MS-103, 1MS-104, 1MS-105, 2MS-17, 2MS-24, 2MS-26, 2MS-33, 2MS-35, 2MS-36, 2MS-76, 2MS-79, 2MS-82, 2MS-84, 2MS-93, 2MS-102, 2MS-103, 2MS-104, 2MS-105, 3MS-17, 3MS-24, 3MS-26, 3MS-33, 3MS-35, 3MS-36, 3MS-76, 3MS-79, 3MS-82, 3MS-84, 3MS-93, 3MS-102, 3MS-103, 3MS-104, and 3MS-105)
Protected Service Water (PSW-14, 1PSW-22, 1PSW-23, 1PSW-24, 1PSW-25, 1PSW-6, 2PSW-22, 2PSW-23, 2PSW-24, 2PSW-25, 2PSW-6, 3PSW-22, 3PSW-23, 3PSW-24, 3PSW-25, and 3PSW-6)
Reactor Coolant System (1RC-1, 1RC-4, 1RC-155, 1RC-156, 1RC-157, 1RC-158, 1RC-159, 1RC-160, 1RC-162, 1RC-163, 2RC-1, 2RC-4, 2RC-155, 2RC-156, 2RC-157, 2RC-158, 2RC-159, 2RC-160, 2RC-162, 2RC-163, 3RC-1, 3RC-4, 3RC-155, 3RC-156, 3RC-157, 3RC-158, 3RC-159, 3RC-160, 3RC-162, and 3RC-163)
Spent Fuel System (SF-166, SF-167, 3SF-166, and 3SF-167)
Siphon Sealing Water (1SSW-155, 1SSW-156, 1SSW-157, 2SSW-155, 2SSW-156, 2SSW-157, 3SSW-155, 3SSW-156, and 3SSW-157)
Turbine Generator Cooling Water (K1WL-11 and K2WL-11) 3.3 Proposed Alternative The licensee is proposing as an alternative to the requirements of ASME OM Code, Subsection ISTC, paragraph ISTC-3700, to apply Code Case OMN-28 for those valves that can be defined, categorized, and documented by engineering justification as "stem-disk separation non-susceptible valve(s) on the basis that compliance with Code Case OMN-28 would result in an acceptable level of quality and safety pursuant to 10 CFR 50.55a(z)(1). To categorize a valve as not susceptible to stem-disk separation, the licensee states that the valve shall have a documented justification that the stem-disk connection is not susceptible to separation based on the internal design, service conditions, applications and evaluation of the stem-disk connection using plant-specific and industry operating experience, and vendor recommendations, as specified in Code Case OMN-28. Valves with remote position indicators that are not susceptible to stem-disk separation shall be verified to accurately represent valve operation, open and closed, in accordance with Code Case OMN-28. No deviations from the Code Case are proposed.
3.4
NRC Staff Evaluation
The licensee proposes to use Code Case OMN-28 in its entirety for the valves listed in its letter dated November 9, 2021. Code Case OMN-28 has been approved by the ASME OM Standards Committee. The Code Case has also been approved by the ASME Board of Nuclear Codes and Standards and is listed in the Applicability Index from ASME Codes and Standards, as applicable through the 2020 Edition of the ASME OM Code. Code Case OMN-28 is expected to be included in the proposed Revision 4 of RG 1.192 for Code Cases acceptable for use, which is currently scheduled to be incorporated by reference in 10 CFR 50.55a in the spring of 2022.
The NRC staff has reviewed the provisions in Code Case OMN-28 to demonstrate that the remote position indicators for valves that are not susceptible to stem-disk separation accurately represent valve operation, open and closed. Code Case OMN-28 requires that this remote position verification for valves that are not susceptible to stem-disk separation shall include the following: (a) observation of evidence, such as changes in system pressure, flow rate, level, or temperature, that represent valve operation; (b) local observation of valve operation where practicable; and (c) stem-disk separation evaluation shall be documented and available for regulatory review demonstrating that the stem-disk connection is not susceptible to separation.
For active valves not susceptible to stem-disk separation, Code Case OMN-28 states that these observations shall be performed at least once every 12 years. For passive valves not susceptible to stem-disk separation, Code Case OMN-28 states that these observations shall be performed whenever the valve is stroked from its passive position or every 12 years, whichever is greater.
In its submittals, the licensee specifies to utilize the provisions of Code Case OMN-28 for those valves that can be defined, categorized, and documented by engineering justification as stem-disk separation non-susceptible valves. Where Code Case OMN-28 is implemented in its entirety, the NRC staff considers that the provisions in Code Case OMN-28 satisfy the requirements in ASME OM Code, Subsection ISTC, paragraph ISTC-3700, as incorporated by reference in 10 CFR 50.55a and supplemented by 10 CFR 50.55a(b)(3)(xi), to provide reasonable assurance that the remote position indicators for valves that are not susceptible to stem-disk separation properly verify the position of the valve obturator.
Based on the above, the NRC staff finds that the implementation of Code Case OMN-28 in its entirety for the valves at Oconee listed in the licensees letter dated November 9, 2021, in lieu of the requirements in ASME OM Code (2017 Edition), Subsection ISTC, paragraph ISTC-3700, as incorporated by reference in 10 CFR 50.55a and supplemented by 10 CFR 50.55a(b)(3)(xi),
provides an acceptable level of quality and safety in accordance with 10 CFR 50.55a(z)(1).
4.0 CONCLUSION
As described above, the NRC staff concludes that the proposed alternative request ON-RPI-OMN-28 provides an acceptable level of quality and safety for the verification of valve position indication for valves that are not susceptible to stem-disk separation in lieu of the requirements in ASME OM Code (2017 Edition), Subsection ISTC, paragraph ISTC-3700, as incorporated by reference in 10 CFR 50.55a and supplemented by 10 CFR 50.55a(b)(3)(xi), for valves at Oconee identified in the licensees letter dated November 9, 2021. 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 proposed alternative in relief request ON-RPI-OMN-28 where implemented in its entirety for the valves identified in the licensees request for the sixth 10-year IST program interval at ONS Units 1, 2, and 3.
All other ASME OM Code requirements for which relief or an alternative was not specifically requested and granted or authorized (as appropriate) remain applicable.
Principal Contributors:
Thomas G. Scarbrough, NRR Yuken Wong, NRR Date: March 15, 2022
ML22068A025 OFFICE NRR/LPL2-1/PM NRR/LPL2-1/LA NRR/DEX/EMIB/ABC NRR/LPL2-1/BC NAME SWilliams KGoldstein ITseng MMarkley DATE 03/08/2022 03/09/2022 03/07/2022 3/15/2022