ML25248A259
| ML25248A259 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 09/10/2025 |
| From: | Markley M NRC/NRR/DORL/LPL2-1 |
| To: | Carr E Virginia Electric & Power Co (VEPCO) |
| Klos J, NRR/DORL/LPL2-1 | |
| References | |
| EPID L-2024-LLR-0083 | |
| Download: ML25248A259 (1) | |
Text
September 10, 2025 Eric S. Carr President - Nuclear Operations and Chief Nuclear Officer Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711
SUBJECT:
SURRY POWER STATION, UNIT NOS. 1 AND 2 - AUTHORIZATION OF PROPOSED ALTERNATIVE REQUEST V-2 INSERVICE TESTING OF ACCUMULATOR DISCHARGE CHECK VALVES (EPID L-2024-LLR-0083)
Dear Eric Carr:
By letter dated December 30, 2024 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML24365A198), as supplemented by letter dated April 8, 2025 (ML25099A136), Virginia Electric and Power Company (the licensee) submitted Alternative Request V-2 to the U.S. Nuclear Regulatory Commission (NRC) requesting authorization of the proposed alternative to use mechanical agitation of accumulator check valves for certain inservice testing (IST) requirements of the 2020 Edition 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 Code of Record interval, as defined in Title 10 of the Code of Federal Regulations (10 CFR) Section 50.55a(y), Definitions, that uses the 2020 Edition of the ASME OM Code, at Surry Power Station, Unit Nos. 1 and 2 (Surry).
Specifically, pursuant to 10 CFR 55.55a(z)(2), the licensee requested that the NRC authorize Alternative Request V-2 for certain check valves at Surry on the basis that compliance with the ASME OM Code requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality or safety.
Accordingly, the NRC staff has reviewed Alternative Request V-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)(2). Therefore, the NRC staff authorizes the use of Alternative Request V-2 at Surry, for the Code of Record interval that uses the 2020 Edition of the ASME OM Code, which began on May 10, 2025.
All other ASME OM Code requirements as incorporated by reference in 10 CFR 50.55a for which relief or an alternative was not specifically requested, and granted or authorized (as appropriate), in the subject request remain applicable.
If you have any questions, please contact the Surry Project Manager at (301) 415-5136, or via email at John.Klos@nrc.gov.
Sincerely, Michael Markley, Chief Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-280 and 50-281
Enclosure:
Safety Evaluation cc: Listserv MICHAEL MARKLEY Digitally signed by MICHAEL MARKLEY Date: 2025.09.10 12:04:26 -04'00'
Enclosure SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION AUTHORIZATION OF ALTERNATIVE REQUEST V-2 SIXTH AND SEVENTH INSERVICE TESTING INTERVAL VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION, UNIT NOS. 1 AND 2 DOCKET NOS. 50-280 AND 50-281
1.0 INTRODUCTION
By a letter dated December 30, 2024 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML24365A198), as supplemented by letter dated April 8, 2025 (ML25099A136), Virginia Electric and Power Company (the licensee) submitted Alternative Request V-2 to the U.S. Nuclear Regulatory Commission (NRC) requesting authorization of the proposed alternative to use mechanical agitation of accumulator check valves for certain inservice testing (IST) requirements of the 2020 Edition of the American Society of Mechanical Engineers (ASME) Operation and Maintenance of Nuclear Power Plants, Division 1 (OM Code) for the Code of Record interval, as defined in Title 10 of the Code of Federal Regulations (10 CFR) Section 50.55a(y), Definitions, that implements the 2020 Edition of the ASME OM Code, at Surry Power Station, Units 1 and 2 (Surry).
Specifically, pursuant to 10 CFR 55.55a(z)(2), Hardship without a compensating increase in quality and safety, the licensee requested that the NRC authorize Alternative Request V-2 for certain check valves to implement at Surry on the basis that compliance with specified requirements of the ASME OM Code would result in hardship or unusual difficulty without a compensating increase in the level of quality or safety.
2.0 REGULATORY EVALUATION
The NRC regulations in 10 CFR 50.55a(f)(4), Inservice testing standards requirement for operating plants, state, in part:
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 [10 CFR 50.55a] and that are incorporated by reference in paragraph (a)(1)(iv) of this section [10 CFR 50.55a], 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), Alternative to codes and standards requirements, state, in part, that alternatives to the requirements of paragraphs (b) through (h) of 10 CFR 50.55a 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.
3.0 TECHNICAL EVALUATION
3.1 Licensees Alternative Request V-2 Applicable ASME OM Code Edition The ASME OM Code of Record for the Sixth and Seventh IST Interval at Surry is the 2020 Edition of the ASME OM Code as incorporated by reference in 10 CFR 50.55a. The Sixth IST Interval began on May 10, 2025.
ASME OM Code Components Affected In its letter dated December 30, 2024, the licensee proposed alternative requirements for certain check valves, as identified in Table 1:
Table 1 Component Number Component Description ASME Code Class OM Category 1/2-SI-107 A Accumulator Discharge Check Valve 1
C 1/2-SI-109 A Accumulator Cold Leg Admission Check Valve 1
C 1/2-SI-128 B Accumulator Discharge Check Valve 1
C 1/2-SI-130 B Accumulator Cold Leg Admission Check Valve 1
C 1/2-SI-145 C Accumulator Discharge Check Valve 1
C 1/2-SI-147 C Accumulator Cold Leg Admission Check Valve 1
C In its letter dated December 30, 2024, the licensee confirmed that the check valves listed in Table 1, above, are 12-inch Anchor Darling swing check valves. Hereafter, this safety evaluation refers to both the discharge check valves and admission valves as ADCVs.
Applicable ASME OM Code Requirements The requirements in the ASME OM Code, as incorporated by reference in 10 CFR 50.55a, related to Alternative Request V-2 include:
Subsection ISTC, Inservice Testing of Valves in Light-Water Reactor Nuclear Power Plants, Paragraph ISTC-5224, Corrective Action, states, in part:
If a check valve fails to exhibit the required change of obturator position, it shall be declared inoperable. A retest showing acceptable performance shall be run following any required corrective action before the valve is returned to service.
Mandatory Appendix II, Check Valve Condition-Monitoring Program, Paragraph II-4000, Condition-Monitoring Activities, states, in part:
Valve obturator movement during applicable test or examination activities shall be sufficient to determine the bidirectional functionality of the moving parts. A full-open exercise test, or an open test to the position required to perform its intended function, is not required for this assessment.
Proposed Alternative and Basis for Use In Section 5 of its letter dated December 30, 2024 (ML24365A198), Section 5, Proposed Alternative, the licensee states, in part, that:
Dominion Energy Virginia is requesting an alternative to ISTC-5224 requirements as they relate to corrective action when the obturator position cannot be confirmed to be in the closed position, i.e., the valve must be declared inoperable, and a retest must be performed following any corrective action; series valve pairs that fail to prevent reverse flow shall be declared inoperable; and both valves shall be either repaired or replaced. The proposed alternative is applicable to the valves listed in Section 1.0 of this alternative request.
Back leakage testing for the ADCVs [accumulator discharge check valves] occurs at low or high pressures to facilitate startup activities.
In Section 5, the licensee lists the actions to be taken when back leakage testing does not meet the acceptance criteria. The licensee further stated:
Using the provisions of this request as an alternative to the specific requirements of ISTC-5224, which have been identified as a hardship without a compensating increase in quality and safety pursuant to 10 CFR 50.55a(z)(2), will provide adequate indication of the function and operability of these ADCVs.
In Section 6 of its letter dated December 30, 2024, the licensee stated that the ACDVs are a standard design check valve model for reactor coolant system (RCS) conditions and typically perform well until operation eventually results in degradation of the seating surfaces,.
In its letter dated December 30,2024, additional justification for its proposed alternative that the NRC staff summarizes below:
- 1. Review of Maintenance History of the ADCVs The licensee provided leakage testing results for ADCVs back to the Cycle 23 refueling outage (RFO) for both units (Fall 2010 for Unit 1 and Spring 2011 for Unit 2). The licensee identified and discussed unsatisfactory testing results and the applicable corrective actions, including disk and hanger arm assembly replacement, and seat lapping. The licensee discussed historically reliable performance of the pressure isolation valves (PIVs) for closure during power operations (seating issues were stated to occur during back leakage testing at lower pressures rather than during power operations) and for opening during accident conditions (credited safety functions). The licensee also stated that no active preventative maintenance tasks are in place for these valves, and they have proven to be reliable. In the supplement dated April 8, 2025 (ML25099A136), the licensee clarified that the leakage testing results provided in Alternative Request V-2 are only those for the back leakage testing within the scope of this request and do not reflect any other type of closure testing.
- 2. Requirements for Application of Mechanical Agitation The licensee described the requirements for the mechanical agitation method to be used for the ADCVs. For example, as-found test results and visual inspection of the valve body for pre-existing damage, markings, and defects are needed to establish the initial condition of the valve. Other methods are used to try to seat the valve prior to use of mechanical agitation, such as variance of pressure or venting. The valve is required to be declared inoperable prior to mechanical agitation. In its submittal dated December 30, 2024, the licensee stated that mechanical agitation is to be performed using a 15-pound (maximum) rubber mallet or soft-faced dead blow hammer swung at a maximum of approximately 120 degrees about the elbow without excessive use of the body to accelerate the hammer head.
In the supplement dated April 8, 2025, the licensee confirmed that the hammer to be used when implementing Alternative Request V-2 is consistent with Alternative Request V-1, in that it will be flat faced or rounded with a hammer face diameter of 1/2 inch or greater. The surface to be agitated shall not include valve bolting or flanges, and the area should be visually inspected after mechanical agitation to ensure no physical external damage occurred. Only the lower two-thirds of the valve body shall be struck, and the valve shall only be struck one time with leakage reassessed prior to striking again. After mechanical agitation, the valve will be retested using normal test procedures. If the ADCV, or series pair, as applicable, subsequently passes the back leakage or closure test, the ADCV, or series pair, shall be repaired or replaced during the next applicable Units RFO. The supplement also confirmed that the valve will be opened and inspected during the next RFO after mechanical agitation to verify there is no internal damage to the valve due to mechanical agitation. Because mechanical agitation is not a repair or replacement activity, this alternative is needed to avoid potential unnecessary emergent demands on plant equipment, resources, and personnel.
- 3. Design of the ADCVs In Section 6(B) of its submittal dated December 30, 2024, the licensee described the design of the ADCVs noting that the failure of a check valve disk to open (i.e., stuck closed), or detachment of the disk from valve internals is normally due to service conditions and/or process fluid. The licensee also stated that most failures are associated with carbon steel valves in raw water systems where the disk is closed for long periods of time, thereby allowing corrosion to bond the disk to other parts of the valve internals. Another failure mechanism of ADCVS is when the disk operates long term in a less than full-open position, thus allowing hinge pin wear in a raw water environment.
The process fluid for the ADCVs at Surry is borated water, which is maintained within strict chemistry and cleanliness standards. The valves are designed for service in a boric acid solution and are comprised of stainless steel materials. The licensee asserts that it is unlikely that the disk will fail to open or become detached when flow is required because the conditions for corrosion are not present and the open position occurs a small percentage of the time.
- 4. Description of ADCV Open Exercise Testing In Section 6(C) of its submittal dated December 30, 2024, the licensee described the open exercise testing of the ADCVs. Specifically, the ADCVs are tested in the open direction at least every other RFO as prescribed by the check valve condition monitoring plan. The partial open test is performed by discharging the contents of the accumulators through the ADCVs to demonstrate the valves are capable of performing their open safety functions. The licensee reported consistent performance with no issues identified during this testing.
Engineering Assessment In its submittal dated the December 30, 2024, Attachment 2, Engineering Assessment of Mechanical Agitation Process for Accumulator Discharge Check Valves, an engineering assessment of the proposed methodology for seating the ADCVs as well as the structural impact of the mechanical agitation was presented. The assessment referenced an NRC safety evaluation for Surry, Unit 1, dated August 12, 2024 (ML24164A001), and an NRC safety evaluation for Sequoyah Nuclear Plant (Sequoyah), Units 1 and 2, dated December 1, 2022 (ML22304A186).
In Attachment 2 of its submittal dated December 30, 2024, the licensee assumed a 20-pound maul would be used. The licensee assessed the Surry 12-inch Anchor Darling swing check valves as bounded by the 6-inch Velan swing check valves within the TVA request for Sequoyah. The licensee used a similar methodology as described in the TVA request, noting that a dynamic load factor of 4 was used in lieu of the value of two, which would result from using the equation for a pendulum coupled with Roarks Formulas for Stress and Strain.
Localized stress was estimated using Roarks Formulas for Stress and Strain, which was found acceptable by the NRC in the Sequoyah and Surry precedents. The assessment concluded that the induced stress is very low compared to the allowable stress and Anchor Darling had no concern for potential valve damage as a consequence of the proposed mechanical agitation method. The licensees guidance includes recommendations to strike the thickest portion of the valve body, to avoid striking the bonnet, to avoid point impact, and, if practical, to use a second
piece of metal plate to distribute the impact force. The assessment contains recommendations for mechanical agitation that the licensee considers consistent with the NRC safety evaluation for the Sequoyah request and the prior Surry request.
=
Reason for Request===
In Section 4, Reason for Request, of its submittal dated December 30, 2024 (ML24365A198),
the licensee stated that post back leakage testing mechanical agitation has been used to facilitate seating of a valve to achieve an acceptable back leakage test result. The licensee recognizes that mechanical agitation is a troubleshooting activity rather than a repair method and also recognizes for series valve pairs tested as a unit that fail to prevent reverse flow, OM Code, ISTC-5224, Corrective Action, requires the valve pair to be declared inoperable and to be either repaired or replaced. The licensee is also aware of precedents where the NRC approved IST alternative requests to use mechanical agitation as a leakage test troubleshooting tool to facilitate valve seating and for deferring repair or replacement of certain check valves to the following RFO.
3.2
NRC Staff Evaluation
At nuclear power plants, PIVs are defined as two valves in series within the reactor coolant pressure boundary that separate the high-pressure RCS from a lower pressure system. The Safety Injection ADCVs and the Accumulator Cold Leg Admission Check Valves at Surry together make a series pair check valve configuration where at least one of the two valves establishes the reactor coolant pressure boundary for each of the three safety injection accumulators. The Surry response to Generic Letter 87-06, Periodic Verification of Leak Tight Integrity of Pressure Isolation Valves, (ML20215B762) identified these valves as PIVs, but did not specify leakage testing acceptance criteria. This response noted that periodic testing in accordance with Technical Specifications and ASME Boiler and Pressure Vessel Code (BPV Code),Section XI, hydrostatic test requirements would verify the integrity of the boundary with interfacing systems but not the integrity of each individual valve. For Surry, these PIVs must be leak tested in accordance with the requirements of the applicable paragraphs of the ASME OM Code (2020 Edition), Subsection ISTC, as incorporated by reference in 10 CFR 50.55a.
Paragraph ISTC-5224 requires that [i]f a check valve fails to exhibit the required change of obturator position, it shall be declared inoperable and a retest showing acceptable performance shall be run following any required corrective action before the valve is returned to service. The NRC staff reviewed the alternative to the applicable PIV leakage testing requirements of the ASME OM Code as incorporated by reference in 10 CFR 50.55a proposed by the licensee in Alternative Request V-2.
For Alternative Request V-2, the licensee stated that the subject ADCVs have been back leakage tested during plant startup from RFOs at low differential pressures (ML24365A198).
The licensee stated that the mechanical agitation method described in Alternative Request V-2 is needed to avoid potential unnecessary emergent demands on plant equipment, resources, and personnel. For example, the licensee stated that a failed test would require reversal of restart activities, including cooldown, depressurization, and reduction of RCS water level, to allow for repair or replacement of the valves. The licensee indicated that this alternative will apply to ISTC-5224 requirements as they relate to corrective action when the obturator position cannot be confirmed to be in the closed position. Based on the submitted information and operating experience with check valve performance, the NRC staff finds that compliance with the applicable requirements in the ASME OM Code would constitute a hardship without a compensating increase in the level of quality and safety. Attempting to obtain a successful back
leakage test for the subject check valves would result in significant maintenance activities, plant personnel radiation exposure, and plant startup delays.
In its letter dated December 30, 2024 (ML24365A198), the licensee stated that for an ADCV, or series pair, within the scope of the request that does not meet the back leakage testing acceptance criteria, the actions listed in Section 5 will be taken.
The NRC staff reviewed the subject actions and finds that these procedural controls will provide reasonable assurance that mechanical agitation will prevent damage to the valve and injury to plant personnel.
In the licensees supplement dated April 8, 2025, the licensee clarified that;
- 1. the proposed duration of Alternative Request V-2 is for the Code of Record interval that uses the 2020 Edition of the ASME OM Code, which corresponds to the Sixth and Seventh IST Interval,
- 2. the back leakage tests are a type of closure test and the only testing discussed within the scope of Alternative Request V-2 is the back leakage testing
- 3. the licensee clarified wording differences between Alternative Requests V-2 and V-1, confirming that the hammer to be used for mechanical agitation will be a flat faced or rounded rubber or dead blow hammer with a hammer face diameter 1/2 inch or greater, and that check valves that have been mechanically agitated will be opened and inspected during the next RFO to verify there is no internal damage to the valve due to mechanical agitation, and
- 4. Alternative Requests V-1 and V-2 share a common evaluation for both Anchor Darling and Velan check valves, receiving input from both valve vendors.
In its letter dated December 30, 2024, the licensee also provided detailed information regarding the maintenance history of the subject PIVs including;
- 1. PIVs have historically demonstrated to be reliable in performing their open and close safety functions and have only experienced seating issues for the close function during back leakage testing at lower pressures.
- 2. no issues have been identified with the PIVs performing their open safety function.
- 3. currently there are no active preventative maintenance tasks in place for these valves because they have proven to be reliable in performing their safety functions and are not subject to inservice conditions that would cause degradation or wear of the valve internals.
Based on the above, the NRC staff finds the subject ADCVs within the scope of Alternative Request V-2 at Surry have an acceptable maintenance history to support the proposed alternative.
In its submittal dated December 30 2024, the licensee specifies that mechanical agitation of the subject ADCVs described in the alternative request is not a repair or replacement activity. The licensee further stated that prior to using mechanical agitation, as-found test results will be obtained and other measures such as varying pressure or venting will be applied, where possible, to seat the check valve. The NRC staff agrees with this approach, as it does not introduce the potential for unacceptable preconditioning of the applicable ADCVs using the mechanical agitation method.
The NRC staff reviewed Attachment 2 of the licensees submittal dated December 30, 2024, that evaluated seating the ADCVs and the structural impact of the mechanical agitation. The NRC staff compared Surry engineering assessment to the plant-specific mechanical agitation method that the staff authorized for Sequoyah, Units 1 and 2, in the NRC safety evaluation dated September 29, 2022 (ML22263A375). The NRC staff also compared the Surry engineering assessment to the plant-specific mechanical agitation method that the staff authorized in the Surry alternative request V-1 safety evaluation dated August 12, 2024 (ML24164A001). The NRC staff finds that the Surry licensee applied a similar plant-specific assessment methodology to that used in the other requests. For example, the Surry licensee estimated localized stress using Roarks Formulas for Stress and Strain, a method which the NRC staff finds to be acceptable as proposed for this application. The NRC staff confirmed, as stated in its supplement dated April 8, 2025, that the valve length was obtained from vendor drawings and the use of the total valve length for calculating the moment applied by the mechanical agitation is consistent with the precedents cited above. The NRC staff determined that the calculated induced stress is very low compared to the allowable stress based on the Surry licensees assessment. In its submittal dated December 30, 2024, the Surry licensee noted that the Anchor Darling valve company had no concern for potential valve damage as a consequence of the method proposed for mechanical agitation of these valves. The NRC staff also confirmed (as stated in ML25099A136) that the licensee intends to implement the controls and processes of mechanical agitation in Alternative Request V-2 in the same manner as the check valves included in Alternative Request V-1.
Therefore, the NRC staff finds that the licensees proposed method for mechanical agitation of the subject ADCVs at Surry is reasonable and provides sufficient plant-specific justification and guidance for implementation.
Based on the above, the NRC staff finds that a hardship or unusual difficulty exists without a compensating increase in the level of quality and safety to perform the specified ASME OM Code requirements for the subject PIVs when their back leakage cannot be mitigated by typical means and could lead to significant maintenance, personnel radiation exposure, and ML25099A136startup delays. The NRC staff evaluated whether the licensee adequately specified the provisions of the mechanical agitation method requested to be authorized for the ADCVs within the scope of Alternative Request V-2 for Surry. The NRC staff also evaluated whether the licensee demonstrated that the stress induced in the subject ADCVs during the mechanical agitation method to be implemented under Alternative Request V-2 will not damage the valve body or cause localized deformation, nor endanger plant personnel performing the mechanical agitation of the subject ADCVs. All required steps discussed in Alternative Request V-2 regarding the use of mechanical agitation for the subject ADCVs will be included in plant procedures at Surry prior to use. The NRC staff finds that the licensee has provided reasonable assurance that the subject ADCVs will be capable of performing their safety functions following the mechanical agitation method described in Alternative Request V-2. As a result, the NRC staff finds that Alternative Request V-2 would continue to satisfy 10 CFR 50.55a(z)(2) for the subject ADCVs at Surry.
The NRC staff notes that the applicable code of record for the Surry Sixth IST interval is the 2020 Edition of the ASME OM Code, as incorporated by reference in 10 CFR 50.55a. The Surry Sixth IST interval began on May 10, 2025. The ASME OM Code (2020 Edition),
Subsection ISTA, General Requirements, paragraph ISTA-3120, Inservice Examination and Test Interval, as incorporated by reference in 10 CFR 50.55a, requires that licensees implement 10-year intervals for their IST programs. The NRC regulations in 10 CFR 50.55a allow licensees to implement the same ASME OM Code as their code of record for
two successive IST program intervals. Therefore, the licensee of Surry could implement the 2020 Edition of the ASME OM Code as incorporated by reference in 10 CFR 50.55a for both the Sixth and Seventh IST intervals required by the ASME OM Code, Subsection ISTA, paragraph ISTA-3120.
4.0 CONCLUSION
Based on the above, the NRC staff concludes that the licensee has provided sufficient justification for its proposed mechanical agitation method described in Alternative Request V-2 to be applied if an ADCV within the scope of the request fails its OM Code-required back leakage test as an alternative to the applicable requirements in the ASME OM Code (2020 Edition) as incorporated by reference in 10 CFR 50.55a. The staff finds that the proposed alternative as specified in Alternative Request V-2 will provide reasonable assurance of the operational readiness of the applicable ADCVs until the next refueling outage when repair and replacement activities will be conducted. The NRC concludes that compliance with the applicable ASME OM Code requirements would result in a hardship or unusual difficulty without a compensating increase in the level of quality and safety. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(z)(2) for Alternative Request V-2. Therefore, the NRC staff authorizes the use of Alternative Request V-2 at Surry for the Code of Record interval, as defined in 10 CFR 50.55a(y), Definitions, that uses the 2020 Edition of the ASME OM Code. Use of this alternative with other codes of record is not authorized.
All other ASME OM Code requirements as incorporated by reference in 10 CFR 50.55a for which relief or an alternative was not specifically requested, and granted or authorized (as appropriate), in the subject request remain applicable.
Principal Contributors: Nicholas Hansing, NRR Thomas Scarbrough, NRR Dated: September 10, 2025
- via eConcurrence ^via email NRR-028 OFFICE NRR/DORL/LPL2-1/PM NRR/DORL/LPL2-1/LA*
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NAME JKlos KZeleznock SBailey DATE 09/02/2025 09/05/25 07/25/2025 OFFICE NRR/DORL/LPL2-1/BC*
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NAME MMarkley JKlos DATE 9/10/2025 9/10/2025