ML21267A094

Rulemaking: Final Rule: Comment Response Document: Incorporate by Reference American Society of Mechanical Engineers Boiler and Pressure Vessel Code and Operations and Maintenance Code

ML21267A094
Person / Time
Issue date:	09/30/2022
From:	Office of Nuclear Material Safety and Safeguards
To:
Huckabay, Victoria
Shared Package
ML21267A036	List: ML21267A091 ML21267A092 ML21267A094 ML21267A098
References
10 CFR Part 50, ASME 2019-2020, Final Rule, NRC-2018-0290, RIN 3150-AK22
Download: ML21267A094 (52)

Text

NRC Responses to Public Comments:

Final Rule:

American Society of Mechanical Engineers 2019-2020 Code Editions NRC-2018-0290; RIN 3150-AK22 U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation September 2022

ABBREVIATIONS AND ACRONYMS ADAMS Agencywide Documents Access and Management System ANII Authorized nuclear inservice inspector ASME American Society of Mechanical Engineers BPV Boiler and Pressure Vessel CFR Code of Federal Regulations CVCM check valve condition monitoring CVCMP check valve condition monitoring program EPRI Electric Power Research Institute FR Federal Register FRN Federal Register notice IP inspection procedure ISI inservice inspection IST inservice testing ISTOG Inservice Testing Owners Group Ksi kilopounds per square inch LLRT local leak rate testing MOV motor-operated valve NDE nondestructive examination NEI Nuclear Energy Institute NRC U.S. Nuclear Regulatory Commission OM Operation and Maintenance PCC Post Construction Committee PRA Probabilistic Risk Assessment PSI preservice inspection QA Quality assurance SPI supplemental position indication TVA Tennessee Valley Authority UFSAR updated final safety analysis report UT ultrasonic testing ii

Introduction This document presents the U.S. Nuclear Regulatory Commissions (NRCs) responses to written public comments received on the proposed rule, American Society of Mechanical Engineers 2019-2020 Code Editions. The NRC published the proposed rule on March 26, 2021, in Volume 86 of the Federal Register (FR), page 16087 (86 FR 16087), for public comment with a 60-day comment period. This document identifies how the NRC dispositioned public comments received on the proposed rule.

Overview of Public Comments The NRC received eight comment submissions on the proposed rule. Table 1 identifies these comment submissions, listed in the order of receipt.

In developing the final rule, the NRC considered all comments received on the proposed rule.

If a response to a public comment resulted in a change to the rule language or the supporting preamble, the NRCs comment response indicates the change made and where the change occurred.

Public comment submissions are available online in the NRC Library at https://www.nrc.gov/reading-rm/adams.html. From this page, the public can access the Agencywide Documents Access and Management System (ADAMS), which supplies text and image files of the NRCs public documents. If you do not have access to ADAMS, or if there are problems accessing the documents in ADAMS, contact the NRCs Public Document Room reference staff by calling 1-800-397-4209 or 301-415-4737, or by sending an e-mail to pdr.resource@nrc.gov. In addition, public comments and supporting materials related to this final rule can be found at https://www.regulations.gov by searching for Docket ID NRC-2018-0290.

Table 1: Comment Submissions Comment ADAMS Accession Commenter Submission ID Number 001 Jeffrey D. Stumb, Dominion Energy ML21140A358 002 Mark Gowin, Inservice Testing Owners Group ML21141A263 003 Terence Chan, Private Citizen ML21144A032 004 Thomas Basso, Nuclear Energy Institute ML21145A172 005 Thomas Vogan, American Society of Mechanical ML21146A041 Engineers 006 David P. Helker, Exelon Generation Company, LLC ML21146A042 007 Ronald Swain, Electric Power Research Institute ML21146A043 008 C.J. Riedl, Tennessee Valley Authority ML21146A150 The NRC reviewed and annotated the comment submissions to identify what the NRC concluded were separate comments within each submission. Accordingly, a single comment submission may have several individual comments associated with it. In this document, the NRC summarized some comments for length and quoted the remainder of the comments verbatim (quoted comments are italicized), and placed each into one of the categories shown below. Several comments give essentially the same position, argument, rationale, or basis. In 3

such cases, the NRC binned similar comments together and provided a single response to the binned comments. At the beginning of each comment, the NRC refers to the specific public comment letter containing the comment in the form [XXX-YY], where XXX represents the Submission ID in Table 1 of this document and YY represents individual, sequential comments as noted in the margin of the annotated copy of the public comments (see ADAMS Accession No. ML21267A098).

Comment Categorization I. American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (BPV) Code,Section III

a. Title 10 of the Code of Federal Regulations (10 CFR) 50.55a(b)(1)(xiii)

II. ASME BPV Code,Section XI

a. 10 CFR 50.55a(b)(2)(xv)

b. 10 CFR 50.55a(b)(2)(xviii)(D)

c. 10 CFR 50.55a(b)(2)(xx)(A)

d. 10 CFR 50.55a(b)(2)(xx)(B)

e. 10 CFR 50.55a(b)(2)(xx)(C)

f. 10 CFR 50.55a(b)(2)(xxv)

g. 10 CFR 50.55a(b)(2)(xxvi)

h. 10 CFR 50.55a(b)(2)(xxxii)

i. 10 CFR 50.55a(b)(2)(xl)

III. ASME Operation and Maintenance of Nuclear Power Plants (OM) Code

a. 10 CFR 50.55a(b)(3)(iv)

b. 10 CFR 50.55a(b)(3)(xi)

c. 10 CFR 50.55a(f)(4)

d. 10 CFR 50.55a(f)(7)

IV. Other Comments

a. Comments in support of proposed rule language

b. Typographical errors Comments and Responses I. ASME BPV Code,Section III

a. 10 CFR 50.55a(b)(1)(xiii),Section III Condition: Preservice Inspection of Steam Generator Tubes Comment 004-01: Prior to the 2017 Code edition, the Section III requirement for PSI

[preservice inspection] for steam generator tubes was required by Section XI and existed to provide a baseline for Section XI exams. It was not related to any inspections or testing required to construct, stamp, or complete the NV-1 form. Therefore, it had no relevance on the Section III construction of the steam generator. It was just provided to support a requirement in Section XI.

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Section XI deleted the requirements for PSI as a Section XI requirement in IWB-2200 via record 10-129 (incorporated in the 2017 Code Edition) and now just states that "Steam generator examinations are conducted in accordance with the program required by the plant Technical Specification."Section XI action 10-129 (incorporated in the 2017 Code Edition) changed IWB-2200(a) to remove steam generator tubing from the category of items requiring PSI prior to initial plant startup and created new Table IWB-2500-1 (B-Q) which states that steam generator examinations are conducted in accordance with the program required by the plant Technical Specification. Therefore,Section XI does not require a Section III manufacturer to provide a PSI for steam generator tubes, nor do they require a PSI for steam generator tubes to be completed prior to initial plant startup.

At the time of the Section III Construction when the manufacturer would perform the PSI, the manufacturer does not have access to the plant Technical Specifications. Therefore, the Section III manufacturer needs to be provided with the inspection requirements and criteria.

To accomplish this a requirement to conduct the PSI with the appropriate inspection criteria would need to be in the Section III Design Specification. Lacking this information any inspection done by the Section III manufacturer could be a meaningless activity at additional cost, since there is no certainty the inspection would meet the requirements of the plant Technical Specifications.

Since the only reason for the Section III requirement for a PSI of steam generator tubes was to support a Section XI requirement, and Section XI removed that requirement, this change to Section III was made to align Section III with the change that had already been incorporated in Section XI. The USNRC condition to require a specific PSI for steam generator tubes be done by the Section III manufacturer imposes additional costs on the manufacturer, is not required for Section III construction, may end up being not used, and is not consistent with Section XI requirements.

NEI recommends 10 CFR 50.55a(b)(1)(xiii) Section III Condition: Preservice Inspection of Steam Generator Tubes not be added to the rule, allowing licensees to determine and specify the requisite testing and inspection, including the appropriate and applicable criteria. ASME also has a similar request in that ASME strongly recommends that this condition be removed in the final rule.

Comment 005-02: Prior to the 2017 Code edition, the Section III requirement for PSI for steam generator tubes was required by Section XI and existed to provide a baseline for Section XI exams. It was not related to any inspections or testing required to construct, stamp, or complete the NV-1 form. Therefore, it had no relevance on the Section III construction of the steam generator. It was just provided to support a requirement in Section XI.

Section XI deleted the requirements for PSI as a Section XI requirement in IWB-2200 via record 10-129 (incorporated in the 2017 Code Edition) and now just states that "Steam generator examinations are conducted in accordance with the program required by the plant Technical Specification."Section XI action 10-129 (incorporated in the 2017 Code Edition) changed IWB-2200(a) to remove steam generator tubing from the category of items requiring PSI prior to initial plant startup and created new Table IWB-2500-1 (B-Q) which states that steam generator examinations are conducted in accordance with the program required by the plant Technical Specification. Therefore,Section XI does not require a Section III manufacturer to provide 5

a PSI for steam generator tubes, nor do they require a PSI for steam generator tubes to be completed prior to initial plant startup.

At the time of the Section III Construction when the manufacturer would perform the PSI, the manufacturer does not have access to the plant Technical Specifications. Therefore, the Section III manufacturer needs to be provided with the inspection requirements and criteria.

To accomplish this a requirement to conduct the PSI with the appropriate inspection criteria would need to be in the Section III Design Specification. Lacking this information any inspection done by the Section III manufacturer could be a meaningless activity at additional cost, since there is no certainty the inspection would meet the requirements of the plant Technical Specifications.

Since the only reason for the Section III requirement for a PSI of steam generator tubes was to support a Section XI requirement, and Section XI removed that requirement, this change to Section III was made to align Section III with the change that had already been incorporated in Section XI. The USNRC condition to require a specific PSI for steam generator tubes be done by the Section III manufacturer imposes additional costs on the manufacturer, is not required for Section III construction, may end up being not used, and is not consistent with Section XI requirements.

Therefore, ASME strongly recommends that this condition be removed in the final rule.

NRC Response to Comments 004-01 and 005-02: The NRC disagrees with these comments.

The NRC is adding these conditions to ensure that (1) newly installed steam generator tubing has an adequate baseline examination, and (2) flaws are dispositioned using the criteria in the design specifications to ensure the steam generator tubings structural integrity and capability to perform its intended safety function. As stated in the proposed rulemaking, previous editions of Section III included these requirements, but they were removed from the 2019 Edition of Section III.

First, the NRC disagrees that preservice inspection of steam generator tubes existed only to provide a baseline for Section XI examinations and that preservice inspection of steam generator tubes is not related to any inspections or testing required to construct, stamp, or complete the ASME BPV Code data report. The NRC notes that Section III, NCA-3252(c),

requires design specifications to identify the preservice inspection requirements that are to be performed. In accordance with Section III, NCA-3252(a), design specifications must provide a complete basis for construction and must not result in construction that fails to comply with the requirements of Section III. Construction includes preservice examination, as established by the definitions of construction and examination in Section III, NCA-9200.Section III, NCA-5220(m) provides that the Authorized Nuclear Inspectors (Inspectors) duties include verifying all preservice examinations have been completed. In accordance with Section III, NCA-9200, a data report certifies that an item was constructed in accordance with the requirements of this Section.Section III, NCA-5290(a) provides that the Inspector shall review data reports and sign them only after he has satisfied himself that all requirements of this Section have been met and that each Data Report certified is a correct record. Hence,Section III requires preservice inspection be performed and dispositioned and verified by the Inspector that preservice inspection has been completed to certify (data reports) that a component meetsSection III. Therefore, preservice inspection of the steam generator tubing 6

is relevant for the construction, stamping and completion of the ASME Code data reports for this Class 1 reactor coolant pressure boundary item, in addition to providing a baseline examination due to the safety significance of the steam generator tubing.

Second, the NRC disagrees that preservice inspection for steam generator tubes is not necessary to be performed prior to initial plant startup and therefore the NRC condition should be deleted. The NRC notes that previous editions of Section III included requirements for preservice inspection of steam generator tubing, but they were removed from the 2019 Edition of Section III. The conditions are necessary because steam generator tubes are a Class 1 reactor coolant pressure boundary that are required to maintain structural integrity. Ensuring the integrity of the steam generator tubing provides reasonable assurance of the ability of the reactor system to perform its safety functions to achieve and maintain a safe shutdown.

Therefore, preservice inspection must be performed, and flaws must be evaluated and adequately dispositioned to ensure the structural integrity of safety-related steam generator tubes, so that the components can be relied on to perform their intended safety function. In addition, if preservice inspection is not performed prior to initial start-up, then there will be no baseline examination for future inservice inspections. Preservice inspection provides the baseline condition of the tubes whereby the data obtained provides an essential function in assessing the nature of indications found in the tubes during subsequent inservice examinations. Both the preservice and inservice inspections must be performed with the objective of finding and characterizing the types of flaws that may be present in the tubes.

Third, the NRC disagrees that the Section III manufacturer would lack the information necessary to perform the inspection. As stated above, the NRC notes that Section III, NCA-3252(c),

specifies that the design specification shall identify (1) those components and/or parts that require a preservice examination and (2) the inspection requirements. In addition, NCA3220(s) states that the owner is responsible for designating the preservice inspection requirements

[NCA-3252(c)]. NCA-3220 also provides that a designee on the owners behalf may perform the activities in NCA-3252(c) for preservice examination, but the responsibility for compliance remains the owners responsibility. Therefore, the appropriate inspection requirements and criteria are available and provided by the owner to the applicable party that will perform the preservice inspection. In addition, the Section III manufacturer may or may not be the party that performs the preservice inspection, since the owner can designate another entity with the necessary qualifications to perform this activity. Therefore, the NRC condition does not impose additional costs on the Section III manufacturer because it merely maintains the requirements included in previous editions.

The NRC did not change the rule as a result of these comments.

II. ASME BPV Code,Section XI

a. 10 CFR 50.55a(b)(2)(xv),Section XI Condition: Appendix VIII Specimen Set and Qualification Requirements Comment 005-13: ASME recommends that the condition be revised to apply only to the 2001 Edition and later editions and addenda. ASME notes that the NRCs markup of 7

the existing regulations included this change, but the proposed change was not included in the Federal Register Notice for the proposed rule.

NRC Response to Comment 005-13: The NRC understands this comment is asking why the proposed revision to § 50.55a(b)(2)(xv) did not appear in the quoted text of the proposed rule at the end of the notice of proposed rulemaking. The proposed deletion was listed in paragraph 2.d. of the amendatory instructions as, In paragraph (b)(2)(xv) introductory text, remove the phrase the 1995 Edition through. According to the Office of the Federal Register instructions for amendatory text, this is how such revisions are expected to appear in proposed rules. This modification was included in the final rule. Additionally, the conditions described in

§ 50.55a(b)(2)(xv) are only applicable to licensees using the 2001-2006 Editions of ASME BPV Code,Section XI. While the comment requested that the condition be made applicable to the 2001 Edition and later editions and addenda, the NRC is not proposing to expand the applicability of this condition. The NRC also notes that the proposed change was discussed in Section III.B, Discussion: ASME BPV Code,Section XI and Section IV, Section-by-Section Analysis (86 FR 16091 and 86 FR 16097, respectively). The NRC plans on removing

§ 50.55a(b)(2)(xv) in its entirety when no licensees are using the 2001 Edition of ASME BPV Code,Section XI, Appendix VIII.

The NRC did not change the rule as a result of this comment.

b. 10 CFR 50.55a(b)(2)(xviii)(D),Section XI Condition: NDE Personnel Certification:

Fourth Provision Comment 007-01: The Electric Power Research Institute has been studying how laboratory practice can be effective in developing UT examiner skills as part of a project we are working on to develop a technical basis for nondestructive examination (NDE) experience requirements for ASME Section XI, Appendix VII, which is scheduled to be published by the end of July, 2021.

As part of that project work, we have determined that experience gained in many aspects of ultrasonic testing (UT) in the lab can be superior to experience gained performing the same examinations in the field, in terms of providing the opportunity for learning and improvement.

Based on our findings, we request that the NRC consider modifying the proposed rulemaking with regard to § 50.55a(b)(2)(xviii) to include allowing up to 45% of required experience hours for initial certification to UT Level II to be obtained through laboratory practice and to allow up to 27% of required experience hours for initial certification to UT Level III to be obtained through laboratory practice.

NRC Response to Comment 007-01: The NRC disagrees with this comment. While the NRC understands that there is ongoing work by EPRI on this subject, the NRC cannot modify a condition based on a technical basis the NRC has not reviewed. Although the study referenced by the comment was scheduled to be published before the NRC completed this rulemaking, it was not available in time to be reviewed and incorporated into the NRCs rulemaking process. However, the NRC may consider changes to this condition based on this research in a future rulemaking, particularly if Section XI, Appendix VII is amended to reflect the research.

The NRC did not change the final rule as a result of this comment.

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c. 10 CFR 50.55a(b)(2)(xx)(A),Section XI Condition: System Leakage Tests: First Provision Comment 005-15: ASME supports the proposed change to limit the condition to the 2001 Edition through the 2002 Addenda. ASME also recommends that the NRC consider removing this condition in the subsequent § 50.55a rule to incorporate by reference the 2021 Edition of Section XI if the 2001 Edition through the 2002 Addenda is no longer incorporated by reference in § 50.55a(a).

NRC Response to Comment 005-15: The NRC agrees with this comment and will consider removing this condition in a future rulemaking.

d. 10 CFR 50.55a(b)(2)(xx)(B),Section XI Condition: System Leakage Tests: Second Provision Comment 005-16: ASME continues to believe that this condition is unnecessary for reasons documented in our letter dated November 30, 2015 to Secretary, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001,

Subject:

Comments on Incorporation by Reference of American Society of Mechanical Engineers Codes and Code Cases, 10 CFR Part 50, RIN 3150-AI97.

NRC Response to Comment 005-16: The NRC disagrees that the condition is unnecessary.

As stated previously in the NRCs analysis of public comments for the 2017 final rule for ASME Codes and Code Cases (ADAMS Accession No. ML16130A531), the NRC disagrees that the additional NDE requirements imposed by 10 CFR 50.55a(b)(2)(xx)(B) are unnecessary. This rulemaking will merely extend the application of this condition to a newer edition of the ASME Code, which has not been revised in a way that would cause the NRC to reconsider the condition.

The staff notes that use of ASME BPV Code Case N-416-4, ASME BPV Code,Section XI, would allow a system leakage test to be performed in lieu of a hydrostatic pressure test before return to service of (1) Class 1, 2, and 3 welded or brazed repairs, (2) fabrication welds or brazed joints for replacement parts and piping subassemblies, or (3) installation of replacement items by welding or brazing. As such, the NRC determined that the rigorous NDE requirements of ASME BPV Code,Section III should be performed when the hydrostatic pressure test is not performed. The reason for this condition is that some earlier construction codes have less stringent NDE requirements than ASME BPV Code,Section III; however, they require a greater pressure than the pressure test required by ASME BPV Code,Section XI. The requirements in ASME BPV Code,Section III for NDE for Class 1, 2, and 3 components generally call for either surface or volumetric examinations, or both. Volumetric examination is generally required for full-penetration welds, and surface examination is required for partial-penetration welds.

The NRC has determined that these NDE requirements, along with a system leakage test, give the same level of quality and safety as the higher pressure hydrostatic test and reduced NDE requirements of earlier construction codes.

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The NRC did not change the final rule as a result of this comment.

e. 10 CFR 50.55a(b)(2)(xx)(C),Section XI Condition: System Leakage Tests: Third Provision Comment 005-17: ASME continues to support the Section XI Code requirements and original technical white paper developed to support the current IWA-5213(b)(2). To date, ASME has not received any technical analysis or evaluation supporting the increased hold time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> for non-insulated components.

NRC Response to Comment 005-17: The NRC disagrees with this comment. ASMEs technical basis for a 15-minute hold time in IWA-5213(b)(2) relies on an argument that the time for leakage to manifest increases linearly with the decrease in flow rate corresponding to the reduction in leak test pressure. However, the relationship of the time for leakage to manifest to the flow rate may not be linear; for example, tight cracks that result in a torturous path may cause the leak rate to act in a nonlinear fashion.

The NRC did not change the final rule as a result of this comment.

f. 10 CFR 50.55a(b)(2)(xxv),Section XI Condition: Mitigation of Defects by Modification Comment 005-20: ASME recommends that the re-examination required by

§ 50.55a(b)(2)(xxv)(B)(3) be changed from once per interval to once every ten years to clarify that the re-examination need not be performed in the current inspection interval if less than 10 years remain in that inspection interval.

NRC Response to Comment 005-20: The NRC agrees with this comment but believes the proposed wording would require unnecessary restrictions on the timing of the reexaminations of the mitigations. The NRC revised the condition to clarify that the reexaminations are required at half the modifications expected life or, if the modification has an expected life greater than 19 years, once per interval, beginning with the 10-year interval subsequent to the mitigation. Section 50.55a(b)(2)(xxv) of this rule reflects this change.

Comment 005-21: ASME suggests that § 50.55a(b)(2)(xxv)(B)(3)(ii) might be clearer if revised to read as follows:

(ii) For buried pipe locations where loss of material has occurred due to external corrosion, the modification must be examined at half its expected life or 10 years, whichever is sooner. Alternatively, when the modification has been recoated prior to return to service, the modification may be examined at half its expected life or during the subsequent 10-year inspection interval after installation, whichever is sooner.

NRC Response to Comment 005-21: The NRC agrees with this comment. The NRC revised the condition as suggested for improved clarity but did not adopt the change exactly as 10

proposed because it would require licensees to examine modifications every 10 years rather than allowing licensees to schedule the examination at any point in the inspection interval.

Instead, the final rule will require licensees to examine modifications with expected life greater than 19 years once per interval starting with the interval subsequent to the mitigation. Section 50.55a(b)(2)(xxv) of this final rule reflects this change.

g. 10 CFR 50.55a(b)(2)(xxvi),Section XI Condition: Pressure Testing Class 1, 2, and 3 Mechanical Joints Comment 003-01: In the proposed rulemaking 86 FR 16087 dated March 26, 2021, NRC proposes to amend 10 CFR 50.55a(b)(2)(xxvi) to require a licensee-defined leak test rather than a Code-required pressure test, to demonstrate leak tightness of ASME Class 1, 2 and 3 mechanical joints. The NRC correctly notes that such a test would not need to meet ASME Code requirements, nor would the examiners of such a test be required to meet ASME personnel qualification requirements. Furthermore, although not specifically mentioned by the staff, such testing procedures also would not need to meet ASME requirements, any ASME documentation requirements would not need to be met, nor would any Authorized Nuclear Inservice Inspector (ANII) involvement be required. In fact, because a leak test under this amended provision is not considered a Code activity, ANII involvement could be specifically disallowed by the licensee.

While it would be good practice by an Owner to document or reference such a test to the associated repair/replacement plan of the affected component, there is no requirement to do so, either within the proposed amendment to this paragraph, or by ASME since all activities related to the leakage test permitted by this amendment is outside the jurisdiction of the ASME Code,Section XI. As a result, if the NRC feels it is important to ensure linkage between the leak test performed to the associated repair/replacement activity in order to effectively

"...continue to monitor operating experience related to mechanical joints ...", it is suggested that NRC consider adding to this amended paragraph, a requirement that states to the effect that the licensee-defined leak test shall be referenced on the relevant repair/replacement plan and/or Form OAR-1, as appropriate for the relevant repair/replacement plan.

NRC Response to Comment 003-01: The NRC agrees with the comment in that the activity covered by this condition is in addition to the requirements in ASME BPV Code,Section XI.

However, the NRC disagrees with the suggestion that the owner-defined leak test should be required to be referenced in the repair/replacement plan and/or the OAR-1 report. It is adequate for the leak test to be documented elsewhere, for example, in the maintenance work package used to execute the activity, so long as the documentation would be available to the ANII or NRC inspectors to verify the activity if necessary.

The NRC did not change the final rule as a result of this comment.

Comment 004-02: NEI recognizes that the NRC has revised this condition to make it somewhat more flexible for licensees. However, the condition still adds unnecessary burden by requiring licensees to make significant changes to their ISI [inservice inspection] repair replacement programs to establish the type of leak test, test medium, test pressure, 11

acceptance criteria that would demonstrate the joints leak tightness, and the qualifications of the personnel who will perform the leak test. Additionally, the condition will add administrative burden to implement these new requirements; all for no additional safety benefit. Licensees Appendix B quality and maintenance programs with the requisite site procedures to inspect and monitor for leakage at mechanical joints are and have been adequate to maintain the integrity of mechanical joints.

The NRC states on FR-2021-03-26 page 16093, . failure of a mechanical joint in the absence of a pressure test and VT-2 exam is unlikely, and the corresponding condition for Section XI pressure testing after repair/replacement activities is not needed for safety. The ASME agrees with this position and accordingly per IWA-4540(b)(1) exempts the replacement of bolts, studs, nuts, or washers from pressure testing.

The revised condition wording still does not address the conflict with the exemptions allowed per ASME IWA-4540(b)(1) without licensees having to submit a letter to obtain NRC approval for a previously approved code allowance.

NEI recommends 10 CFR 50.55a(b)(2)(xxvi) Section XI Condition: Pressure Testing of Class 1, 2, and 3 Mechanical Joints be completely deleted from the new rule since it results in no additional safety benefit while increasing unnecessary administrative burden for licensees.

NRC Response to Comment 004-02: The NRC disagrees with the comment that this will add significant burden to licensees by requiring modifications to their ISI repair/replacement programs. The condition does not require licensees to do anything to ISI repair/replacement programs. It simply states that licensees will perform a leak check when they perform repair replacement activities on these joints to ensure leak tightness. The NRC agrees with the comment in that this leak check is something that licensees Appendix B program should provide adequate standards for as part of the post maintenance testing requirements of the program. However, the condition is necessary to ensure that a leak check is required to ensure leak tightness and the long-term structural integrity of the joint. This condition is necessary because of (1) the ASME BPV Code,Section XI, position that pressure testing is not required for mechanical connections and (2) the specific exemptions from pressure testing allowed by the Code. As stated in the comment, the NRC believes failure of a mechanical joint in the absence of performing a Section XI pressure test and VT-2 examination is unlikely.

However, the NRC understands this is due to post maintenance testing currently performed in accordance with licensee Appendix B programs. The condition is necessary to ensure that licensees understand that although Section XI does not require a pressure test, the leak tight integrity of the joint still must be verified to an appropriate standard for nuclear applications.

From comments received on this rulemaking and previous rulemakings this condition appears necessary.

The NRC has disagreed with ASME on the subject of pressure testing of mechanical joints since the original 10 CFR 50.55a(b)(2)(xxvi) condition was established in the final rule dated October 1, 2004 (69 FR 58804). The NRC has maintained that when repair/replacement activities are performed on mechanical joints, an activity should be performed to ensure leak tightness of the joints. Previously, the NRC had said this activity should be a pressure test and VT-2 examination in accordance with Section XI. The condition, as revised in the final rule, allows this activity to be a leak tight verification performed to the standards of a licensees 12

Appendix B program. This is consistent with recommendations of the ASME Post Construction Committee (PCC), which develops and maintains standards addressing common issues and technologies related to post construction activities used by nonnuclear industries.

The NRC disagrees that this condition still does not address the asserted conflict with the exemptions allowed in accordance with ASME IWA-4540(b)(1). The exemptions allowed by IWA-4540(b) are from Section XI pressure testing; the proposed condition does not require any Section XI pressure testing. However, licensees should still perform post maintenance testing to ensure leak tightness. The NRC disagrees with the comment that 10 CFR 50.55a(b)(2)(xxvi) should be deleted because it provides no safety benefit while increasing administrative burden.

While the NRC believes licensee Appendix B programs provide adequate standards for the conducting of tests to verify leak tightness of mechanical joints impacted by repair/replacement activities, the condition makes it clear that the NRC expects this to occur to minimize future bolting degradation. If it is correct that this verification of leak tightness is already part of licensees post maintenance programs, then this condition will not result in any new activities.

The NRC revised the final rule to allow licensees to conduct the leak test in accordance with their Appendix B programs as a result of this and other comments.

Comment 005-22: ASME supports the NRCs proposal to eliminate the requirement to perform a pressure test and VT-2 examination in accordance with IWA-5211(a) of mechanical connections in Class 1, 2, and 3 piping and components greater than NPS-1 which are disassembled and reassembled during the performance of a Section XI repair/replacement activity requiring documentation on a Form NIS-2. However, ASME continues to believe that this condition, including the proposed change, is unnecessary, based on comments submitted during the previous rulemaking to incorporate by reference the 2017 Edition of the ASME Code,Section XI, and for reasons listed below:

1. ASME considers the disassembly and reassembly of a mechanical joint to be a maintenance activity that is not subject to Section XI repair/replacement requirements, unless the reassembly involves the installation of replacement pressure retaining parts or components in the mechanical joint, or the activity involves welding or brazing on parts or components in the mechanical joint. ASME also considers the disassembly of a mechanical joint solely to facilitate the performance of a repair/replacement activity that does not affect the mechanical joint to be a maintenance activity. As proposed, Owners could interpret this condition to apply, even if the repair/replacement activity is not being performed on items within the mechanical joint, or if the repair/replacement activity is exempt from pressure testing in accordance with IWA-4540(b). In these cases, ASME believes that there is no technical reason to require Section XI pressure testing and VT-2 examination. Post-maintenance pressure testing performed in accordance with an Owners procedures should be sufficient to verify that the reassembled mechanical joint is leak-tight.

2. In order to comply with the proposed condition, an Owner would be required to document the type of leak test, test medium, test pressure, acceptance criteria, and personnel qualifications for leakage tests that would demonstrate the joints leak tightness following a repair replacement activity requiring documentation on an NIS-2 form. Currently, this level of detail may not exist in the Owners procedures for post-maintenance leakage testing, and the 13

addition of these requirements creates an unnecessary burden for the utilities with no corresponding increase in quality or safety. To comply with the proposed condition, an Owner may have to revise their post-maintenance test procedures to include these additional requirements.

3. Owners quality assurance programs already require verification of leak tightness following maintenance activities, and ASME believes that the leak-tight integrity of mechanical connections can be assured without the proposed condition.

NRC Response to Comment 005-22: The NRC disagrees with the comment that this condition is unnecessary. The NRC has disagreed with ASME on the subject of pressure testing of mechanical joints, since the original 10 CFR 50.55a(b)(2)(xxvi) condition was established in the final rule dated October 1, 2004 (69 FR 58804). When repair/replacement activities are performed on mechanical joints an activity should be performed to ensure leak tightness of the joints. The Section XI position on this appears to be in conflict with the ASME PCC, which develops and maintains standards addressing common issues and technologies related to post construction activities used by non-nuclear industries. The PCC has developed PCC-1, Guidelines for Pressure Boundary Bolted Flange Joint Assembly, for maintaining flanged joints, which has been referenced in American Petroleum Institute and National Board of Boiler and Pressure Vessel Inspectors Inspection Code standards. PCC-1 requires an owner defined leak test, which is generally accepted as a good engineering practice.

For the reasons in the response to Comment 004-02, the NRC agrees that this condition should not result in any new activities, but that documentation and performance of the verification is necessary.

The NRC did not change the final rule as a result of this comment.

Comment 005-23: ASME strongly recommends that this condition be removed from the final rule.

If the NRC does not accept ASMEs recommendation to remove this condition in the final rule, ASME recommends that the NRC consider revising this condition to address the following:

1. In lieu of specifying that The owner shall establish the type of leak test, test medium, test pressure, acceptance criteria that would demonstrate the joints leak tightness, and the qualifications of the personnel who will perform the leak test, ASME recommends that this sentence be deleted, and instead specify that Leak-testing mechanical joints shall be performed in accordance with IWA-5211(a) in the 2001 Edition through the latest edition and addenda incorporated by reference in paragraph (a)(1)(ii) of this section, or in accordance with requirements of the Owners Quality Assurance Program. This would allow Owners to avoid having to revise their current procedures to implement the revised condition.

2. This condition should not apply to mechanical joints that are disassembled and reassembled during the performance of a repair/replacement activity requiring documentation on an NIS-2 Form if the pressure retaining parts or components in the mechanical joint are not affected by the repair/replacement activity. ASME notes that a pressure test in accordance with IWA-4540 14

would be required if a repair/replacement activity performed by welding or brazing on pressure retaining parts or components in the mechanical joint is not exempt by IWA-4540(b).

NRC Response to Comment 005-23: The NRC disagrees with changing the condition to reference IWA-5211(a), as that would continue to require a Section XI pressure test. The NRC disagrees that the condition should not apply to those items documented on the NIS-2 form.

The NRC believes that referencing the documentation on an NIS-2 keeps the scope the same as the original condition in the final rule dated October 1, 2004 (69 FR 58804), which will ensure joints impacted by repair/replacement activities will be verified to be leak tight and will support long-term structural integrity of the components.

The NRC did not change the final rule as a result of this comment.

Comment 006-01: Exelon recommends (xxvi)Section XI condition: Pressure Testing of Class 1, 2, and 3 Mechanical Joints not be added to the Rule as currently proposed, but rather we suggest it should be deleted entirely.

Licensee's Appendix B Quality Assurance programs already address leakage inspections of mechanical connections outside of ASME Section XI IWA-5000 pressure testing requirements.

The language of the proposed Rule creates a new qualification and inspection program for leak checks by requiring licensees to establish the type of leak test, test medium, test pressure, acceptance criteria that would demonstrate the joints leak tightness, and the qualifications of the personnel who will perform the leak test. Based on the previous requirements under this paragraph most licensees adopted using the 2017 Edition of ASME Section XI for exemptions from the IWA-4540(b) requirements without adding any conditions for standard leak checks performed at nominal operating pressure and temperature outside of ASME Section XI required tests.

NRC Response to Comment 006-01: The NRC disagrees with removing this condition. As the comment indicates, the condition requires actions that licensees should already be performing. The specification of the type of test, test medium, test pressure acceptance criteria, and qualifications was meant to be a list of general items that are usually needed to ensure the activity is done as expected.

The NRC agrees with the comment in that this leak check is something that licensees Appendix B program should provide adequate standards for as part of the post maintenance testing requirements of the program. However, the condition is necessary to ensure that a leak check is required to ensure leak tightness and the long-term structural integrity of the joint. This condition is necessary because of (1) the position in ASME BPV Code,Section XI, that pressure testing is not required for mechanical connections and (2) the specific exemptions allowed from pressure testing allowed by the ASME BPV Code. As stated in the comment, the NRC believes failure of a mechanical joint in the absence of a Section XI pressure test and VT-2 examination is unlikely. However, the NRC understands this is due to post maintenance testing currently performed in accordance with licensee Appendix B programs. The condition is necessary to ensure that licensees understand that although Section XI does not require a pressure test, the leak tight integrity of the joint still must be verified to a standard appropriate for nuclear 15

applications. From comments received on this rulemaking and previous rulemakings this condition appears necessary.

The NRC revised the final rule to allow licensees to conduct the leak test in accordance with their Appendix B programs as a result of this and other comments.

Comment 008-02: TVA concurs with the NRCs proposal to eliminate the ASME Code pressure test and VT-2 examination of mechanical connections in § 50.55a(b)(2)(xxvi) because the same leak test procedures that are used for non-ASME Code repair and replacement will provide adequate assurance of leak tightness. However, TVA recommends to accomplish this objective that 10 CFR 50.55a(b)(2)(xxvi) be deleted entirely, or, alternatively, replaced with the following:

Mechanical joints in Class 1, 2, and 3 piping and components greater than NPS-1 which are disassembled and reassembled during the performance of a Section XI repair/replacement activity shall be verified to be leak tight in accordance with the licensees Appendix B program.

This would eliminate requirements that may be more specific than those utilized in licensees existing non-Code leak test procedures, and for which the technical basis for such differentiation is unclear.

First, the proposed rule requires the owner document the type of leak test, test medium, test pressure, and acceptance criteria that would demonstrate the joints leak tightness when performing a leakage test following a repair/replacement activity requiring a NIS-2 form.

Specifics with these details may not exist in the licensees non-Code leak test procedures, which are developed and maintained in accordance with the licensees Appendix B QA [quality assurance] program, and which, as noted in the proposed rule discussion, support the qualitative risk analysis that concluded elimination of the Section XI pressure test and VT-2 examination resulted In a very low risk of failure.

Therefore, TVA recommends that the proposed rule language be revised to either 1) eliminate the requirement entirely, or 2) revise the language to simply require verification of leak tightness in accordance with the sites QA program requirements.

Second, the proposed rule requires licensee to specify the qualification requirements for the person performing the leak test. Typically, maintenance organization personnel qualified in accordance with the sites Appendix B program will perform the field walkdown, in accordance with site Appendix B procedures, to ensure no leakage exists following reassembly of a mechanical connection. This method of leak detection has been successfully utilized for many years in the industry. Creation of an additional personnel qualification requirement in the sites non-Code leak inspection program, even if owner-defined, creates an unnecessary burden for the utilities with no corresponding increase in quality or safety. It is recommended that this requirement be removed from the proposed rule.

Lastly, the technical basis for these proposed additional requirements is unclear, particularly when applied only to mechanical connections assembled as part of a repair or replacement 16

activity requiring an NIS-2 form. Hypothetically, if a 2-inch ASME Code Class 2 socket weld fails due to thermal fatigue, and the adjacent mechanical connection is disassembled and later reassembled to support the performance of that socket weld repair/replacement activity, that mechanical connection should not necessitate any more rigorous leakage test than it would if the same connection were disassembled and reassembled for any other reason. It is appropriate for mechanical connections to be subject to a leakage test when reassembled, regardless of the reason for the disassembly and reassembly, and the standards applied to those tests should be the same. The purpose of this post-maintenance leakage test is to verify adequate maintenance practices and ensure good housekeeping. By design, leakage at mechanical connections is not a condition that affects the structural integrity of a piping system.

For that reason, TVA recommends that 10 CFR 50.55a(b)(2)(xxvi) should be deleted altogether or rewritten to state simply that verification of leak tightness according to the licensees Appendix B program is required for Class 1, 2, and 3 mechanical joints.

TVA recommends that 10 CFR 50.55a(b)(2)(xxvi) be deleted entirely, as it increases licensee burden, but provides no quality or safety benefit.

Alternatively, 50.55a(b)(2)(xxvi) should be replaced with Mechanical joints in Class 1, 2, and 3 piping and components greater than NPS-1 which are disassembled and reassembled during the performance of a Section XI repair/replacement activity shall be verified to be leak-tight in accordance with the licensees Appendix B program.

NRC Response to Comment 008-02: The NRC disagrees with eliminating the condition completely because the leak tightness of these joints needs to be verified as a post maintenance activity to prevent bolting degradation inservice, as discussed in previous comment responses. The NRC did not intend to add additional documentation or administrative burden and, therefore, changed the final rule to adopt the commenters proposal, with changes to ensure that verification is required independent from Appendix B requirements.

The comments proposed revision is consistent with the intent of the proposed rule but eliminates some of the concerns raised by this and other comments about creating new procedural or administrative requirements, which was not the NRCs intent.

The NRC revised the final rule to allow licensees to conduct the leak test in accordance with their Appendix B programs as a result of this and other comments.

h. 10 CFR 50.55a(b)(2)(xxxii),Section XI Condition: Summary Report Submittal Comment 005-25: ASME supports the proposed change to these administrative requirements, but recommends that the condition not be limited to the 2010 Edition and later editions and addenda. Some U.S. plants may still be using the 2007 Edition with the 2008 Addenda, and ASME would like to see the use of the extended timeframe for submitting the Owners Activity Reports permitted for those plants, as well as those using the 2010 Edition and later editions and addenda.

NRC Response to Comment 005-25: The NRC agrees with not limiting the flexibility of licensees using the 2007 Edition with 2008 Addenda. However, the 10 CFR 50.55a(b)(2)(xxxii) 17

condition only applies to those plants on the 2010 Edition and later because earlier editions include their own reporting provisions. The NRC expects by the time this final rule is published it will have completed a separate rulemaking to incorporate by reference a Section XI Code Case that, if implemented, would allow licensees the added flexibility of the 120-day submittal.

The NRC did not change the final rule as a result of this comment.

Comment 006-02: Exelon recommends (xxxii)Section XI condition: Summary report submittal not be added to the Rule as proposed, and instead of requiring submittal of Summary Reports and Owners Activity Reports, that these reports be made available upon request to the regulatory authority having jurisdiction at the plant site and to the enforcement authority.

Based on numerous information requests associated with the NRC IP 71111.08 Inservice Inspection Activities it does not appear that NRC staff is actively reviewing submitted Summary Reports or Owners Activity Reports until prior to the next scheduled refueling outage when requests for information associated with the IP 71111.08 inspection are developed. Allowing licensees to prepare the Summary Reports or Owners Activity Reports without formally submitting them alleviates administrative burden while still making these documents available to NRC staff for review if requested.

NRC Response to Comment 006-02: The NRC disagrees with not including this condition in the final rule. The NRC believes that summary reports must continue to be submitted to the NRC because they provide valuable information regarding examinations performed, conditions noted, corrective actions taken, and the implementation status of preservice inspection and ISI programs.

While NRC regional inspectors may request additional information based on previous submittals of the Summary reports or Owners Activity reports, these requests follow-up on specific activities inspected under NRC Inspection Procedure (IP) 71111.08, Inservice Inspection Activities. These reports are also used by other NRC employees to gather important information about the status of examinations, codes of record, and indications of degradation found. Recent changes to the Code also make these reports the only submittal of flaw evaluations to justify components for continued operation using code procedures when flaws exceed the acceptance standards of the Codes IWX-3000 tables. Furthermore, going forward these reports will also capture the details of examinations with limited coverage that have been evaluated and found acceptable in accordance with ASME Code Case N-711-1, Alternative Examination Coverage Requirements for Examination Category B-F, B-J, C-F-1, C-F-2, and R-A Piping WeldsSection XI, Division 1. It will be important for the NRC staff to track licensees use of this Code Case to verify the evaluations of these examinations are being performed with adequate rigor. Previously, these examinations had only been accepted through submittal of relief requests, which provided the NRC staff a separate opportunity to review the rigor of the examinations.

The NRC did not change the final rule as a result of this comment.

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i. 10 CFR 50.55a(b)(2)(xl),Section XI Condition: Prohibitions and Restrictions on Use of IWB-3510.4(b), IWC-3510.5(b), Table A-4200-1, and Table G-2110-1 Comment 005-26: ASME does not support the restriction on the use of IWB-3510.4(b)(5) and IWC-3510.5(b)(5) for SA-508 Class 1 material, and recommends that this condition be revised in the final rule so that it does not apply to SA-508 Class 1 material.

[Additional supporting information provided with comment 005-26:]

SA-508 Class 1 designation was changed to SA-508 Grade 1 during the 1990s. SA-508 Class 1 has a specified minimum yield strength (YS) at room temperature of 36 ksi [kilopounds per square inch] as provided in ASME Section II Part A and Part D. Because its specified minimum YS does not exceed 50 ksi, SA-508 Class 1 is among the permitted materials by IWB-3510.4(a) and IWC-3510.5(a). Furthermore, SA-508 Class 1 has always been permitted by Section XI Appendix G-2110(a) to use the minimum curve in Figure G-2210-1 since Section XI Appendix G was first adopted in 1987. Note, SA-508 Class 1 is listed as SA-508-1 in G-2110(a), and the minimum curve of Figure G-2210-1 was changed from KIa to KIc in 1999.

As a background, IWB-3510.4(b)(5) and IWC-3510.5(b)(5) were provided in those paragraphs for information purposes only, and for ease of use to the Code users. The long-term goal of the IWB-3510.4 and IWC-3510.5 paragraphs were to identify commonly used ferritic materials in the nuclear industry when applying the Acceptance Standards in IWB-3500. It should be noted, neither ASME Section XI nor 10 CFR 50 Appendix G requires fracture-mechanics test data of ferritic steels with specified minimum YS not higher than 50 ksi (including SA-508 Class 1).

In light of the above, the proposed condition (restriction or prohibition) on IWB-3510.4(b)(5) and IWC-3510.5(b)(5) should be removed for SA-508 Class 1.

Comment 005-27: The proposed condition (restriction or prohibition) on SA-533 Type B Class 2 is unnecessary and ASME recommends that this condition be removed in the final rule.

[Additional supporting information provided with comment 005-27:]

Prior to the 2019 edition,Section XI G-2110(b) requires fracture-mechanics test data for materials with specified minimum YS between 50 and 90 ksi before the lower-bound minimum KIc curve in Figure G-2210-1 can be used. The minimum KIc curve is identical in Figure A-4200-1 and Figure G-2210-1.

SA-533 Type B Class 2 has a specified minimum YS of 70 ksi; therefore, fracture-mechanics test data were required by Section XI Appendix G-2110(b) prior to the 2019 edition.

The fracture-mechanics test data requirement of G-2110(b) is also imposed by 10 CFR 50 Appendix G. The 2019 edition of Section XI Appendix G-2110(b) and Code Case N-890 exempted the following four grades of ferritic steels with specified minimum YS of 65 or 70 ksi:

• SA-508 Grade 2 Class 2 (former designation SA-508 Class 2A)

• SA-508 Grade 3 Class 2 (former designation SA-508 Class 3A)

• SA-533 Type A Class 2 (former designation SA-533 Grade A Class 2) 19

• SA-533 Type B Class 2 (former designation SA-533 Grade B Class 2)

Per the proposed rule for approval of ASME Code Cases, 86 FR 7820, NRC-2017-0025, (https://www.federalregister.gov/documents/2021/02/02/2021-00890/approval-of-american-society-ofmechanical-engineers-code-cases), the Staff stated that the condition on SA-533 Type B Class 2 material in Code Case N-890 was because:

SA-533 Type B, Class 2 materials, the NRC observed that in the technical basis document, there is no fracture toughness data associated with the weld and heat affected zone to support exclusion of the fracture toughness testing requirements for these materials The technical basis including supporting fracture-mechanics test data was presented in PVP2019-93988 Technical Basis for Expansion of ASME BPVC Section XI, KIc Curve Applicability. Of the four grades of ferritic steels, only SA-533 Type B Class 2 will be restricted or prohibited by the proposed rules, due to a lack of fracture-mechanics test data for weld and HAZ.

The following fracture-mechanics test data for SA-533 Type B Class 2 were not included in PVP2019- 93988 because they were uncovered after the paper was already accepted for publication:

• J.R. Hawthorne and T.R. Mager, Relationship Between Charpy V and Fracture Mechanics KIc, Assessments of A533-B Class 2 Pressure Vessel Steel, Fracture Toughness, Proceedings of the 1971 National Symposium on Fracture Mechanics, Part II, ASTM STP 514, 1972, pp. 151-263

• K. Hayashi, et al., High Performance Steel Plates for Tanks and Pressure Vessels -

High Strength Steel Plates with Excellent Weldability and Superior Toughness for Energy Industry, JFE No. 5, 20048 p. 56-62 [JEF Technical Report No 5,

p. 56-62, August 2004]

Hawthorne, 1972 The testing was performed by Naval Research Laboratory and Westinghouse. The test material was removed from a 6-3/8-thick plate per ASTM A-533 Type B Class 2. ASTM A-533 Type B Class 2 is identical to SA-533 Type B Class 2. Table 1 lists the chemical composition and unirradiated room-temperature tensile property, which met SA-533 Type B Class 2 requirements.

Figure 1 plots the unirradiated KIc data assuming RT-NDT = 0°F. The unirradiated T-NDT was 0°F; RT-NDT was not reported because RT-NDT was first adopted by Section III, NB-2300 in 1973. Judging from the unirradiated Charpy curve, the unirradiated RT-NDT per NB-2300 definition may be higher than T-NDT. If RT-NDT were higher than 0°F, the plotted KIc test data in Figure 1 would shift toward the left, resulting in higher margin against the minimum KIc curve than shown in Figure 1. Therefore, the KIc test data exceeded the minimum KIc curve in Figure G-2210-1 and Figure A-4200-1.

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Hayashi, 2004 The testing was performed by JEF Steel in Japan. The test material was removed from a 120-mm-thick (4.7-thick) plate of Japanese SQV2B steel, which is equivalent to ASME SA-533 Type B Class 2. Table 2 lists the chemical composition and room-temperature tensile property, which met SA-533 Type B Class 2 requirements.

Figure 2 plots the KIc and KId test data. The RT-NDT was -33°C (-27°F). Figure 2 shows that the KIc test data exceeded the minimum KIc curve in Figure G-2210-1 and Figure A-4200-1.

The KIc test data were significantly above the KId test data, and even the KId test data met the minimum KIc curve.

Discussion The above test data for SA-533 Type B Class 2 were not included in PVP2019-93988; they provide additional support to the PVP2019-93988 conclusion that the four grades of ferritic steels can be considered as one group for the applicability of the minimum KIc curve in Section XI Appendix A and Appendix G. In light of the additional test data, the proposed condition (restriction or prohibition) on SA-533 Type B Class 2 is unnecessary.

Table 1, ASTM A-533 Type B Class 2 [Hawthorne, 1972]

[Not reproduced]

Table 2, SQV2B [Hayashi, 2004]

[Not reproduced]

Figure 1, KIc vs T-RTNDT for ASTM A-533 Type B Class 2 [Hawthorne, 1972]

[Not reproduced]

Figure 2, KIc and KId vs T-RTNDT for SQV2B [Hayashi, 2004]

[Not reproduced]

Code Interpretation on ASME Section III Appendix G-2110 (b) requirements The original technical basis for the ASME IWB-3510.4(b), was based on data presented in PVP2010-25214, Facture Toughness of Pressure Bo0undary Steels with Higher Yield Strength, by Gupta, Hoffman, Hamilton, DeLose, July 2010.

As discussed in PVP2010-25214, the authors submitted an ASME Section III Inquiry in November 2008 on the amount of testing data required per G-2110(b) for similar materials with minimum specified yield strength greater than 50 ksi. The ASME Section III Committee provided the interpretation (III-1-07-47, File 08-1636) that the ASME Section III Appendix G-2110(b) requirements (same asSection XI G-2110(b)) apply to a group of like materials rather than to each specific grade of material. Based on this inquiry (as shown below),

the fracture toughness testing data for SA-533 and SA-508 Class 2 materials can be used as a combined set to determine that the KIc curve can be used to bound similar types of base materials, including HAZ and weld metals.

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Therefore, since the Staff has already approved the use of SA-508 Grade 2, Class 2, SA-508 Grade 3, Class 2, and SA-533 Type A Class 2 in ASME Section XI IWB-3510.4(b), then per the Code Interpretation III-1-07-47 (shown below), SA-533 Type B Class 2 is also an acceptable material for use as part of IWB-3510.4(b) and IWC-3510.5(b) ), based on the combined set of fracture toughness data for (65 ksi and 70 ksi) materials of SA-533 and SA-508, which also include HAZ and weld metals, as provided in PVP2010-25214.

Subject:

Section III, Division 1, Nonmandatory Appendix G, Fracture Toughness Criteria for Protection Against Failure, Para. G-2110(b)

Date Issued: 11/24/2008 Record Number: 08-1636 Interpretation Number: III-1-07-47 Question: Does a combined set of fracture toughness data for SA-533 plate and SA-508 forging Class 2 materials, with minimum specified yield strengths greater than 50 ksi (350 MPa) but not exceeding 90 ksi (620 MPa), satisfy the requirements of G-2110(b), when three or more heats of base metal test data are available for plates and for forgings and at least three sets of test data are available on HAZ and weld metal for each specification for one or more grades of the plate and forging materials?

Reply: Yes.

NRC Response to Comments 005-26 and 005-27: The NRC agrees that the prohibition or restriction on the use of SA-508 Class 1 and SA-533 Type B Class 2 should be removed.

The ASME 2015-2017 Code Editions in a previous notice (85 FR 26540) included specific ferritic materials with minimum specified yield strength values of 50 ksi to 90 ksi for which the ASME BPV Code fracture toughness (KIC) curve and the flaw acceptance standards cited in ASME BPV Code,Section XI, IWB-3510.4, are applicable. The 2019-2020 Code Editions in the current rulemaking included the same specific ferritic materials from the ASME 2015-1027 Code Editions to other parts of the ASME Code, namely, IWC-3510.5 and Appendices A and G to Section XI of the ASME Code.

Use of the ASME BPV Code KIC curve and the flaw acceptance standards cited in ASME BPV Code IWB-3510.4 and IWC-3510.5 is limited to ferritic materials with a minimum specified yield strength of 50 ksi or less, unless KIC data for higher strength ferritic materials (minimum specified yield strength values 50 ksi to 90 ksi) are shown to be bounded by the ASME BPV Code KIC curve.

SA-508 Class 1 was one of the materials included with the higher strength ferritic materials (minimum specified yield strength values 50 ksi to 90 ksi) in the ASME 2015-2017 Code Editions, and the NRC prohibited its use because no KIC data were provided to show that the fracture toughness was bounded by the ASME Code KIC curve. The additional supporting information provided with comment 005-26 clarified that SA-508 Class 1 was listed with other 22

materials having a minimum specified yield strength greater than 50 ksi for information purposes only. The additional information in the comment also clarified that SA-508 Class 1 has a minimum specified yield strength of 50 ksi or less, for which the IWB-3510.4 and IWC-3510.5 acceptance standards and the ASME BPV Code KIC curve are applicable without the need to obtain KIC test data. The NRC confirmed that the minimum specified yield strength of SA-508 Class 1 is 50 ksi or less. Therefore, the NRC determined that the IWB-3510.4 and IWC-3510.5 acceptance standards and the ASME BPV Code KIC curve are applicable to SA-508 Class 1.

SA-533 Type B Class 2 was also one of the materials included with the higher strength ferritic materials (minimum specified yield strength values 50 ksi to 90 ksi) in the ASME 2015-2017 Code Editions, and the NRC prohibited its use because few KIC data points were provided to show that the fracture toughness was bounded by the ASME BPV Code KIC curve. The NRC confirmed that the minimum specified yield strength of SA-533 Type B Class 2 is greater than 50 ksi; thus, KIC test data of the material are needed to demonstrate applicability of the IWB-3510.4 and IWC-3510.5 acceptance standards and the ASME BPV Code KIC curve.

The additional supporting information provided with comment 005-27 provided KIC test data for SA-533 Type B Class 2 from two sources that showed that the KIC values were bounded by the ASME BPV Code KIC curve. The NRC confirmed that (1) the data obtained were for SA-533 Type B Class 2 or equivalent, (2) the specimens used in the testing were within the chemical composition specifications of SA-533 Type B Class 2, and (3) the KIC values were bounded by the ASME BPV Code KIC curve. Therefore, the NRC determined that the IWB-3510.4 and IWC-3510.5 acceptance standards and the ASME BPV Code KIC curve are applicable to SA-533 Type B Class 2.

The NRC removed condition 10 CFR 50.55a(b)(2)(xl) from the final rule as a result of these comments.

III. ASME OM Code

a. 10 CFR 50.55a(b)(3)(iv), OM Condition: Check Valves (Appendix II)

Comments 002-01, 004-03, and 008-03: 10 CFR 50.55a(b)(3)(iv) OM Condition: Check Valves (Appendix II) should be revised to be applicable to all addenda and editions of OM endorsed for use. In addition, the overly restrictive language At least one of the identified activities for a valve group shall be performed on each valve of the group at approximately equal intervals not to exceed the maximum interval shown in Table II-4000-1 should be revised to simply require compliance with the maximum intervals (both columns) shown in Table II-4000-1.

This will provide flexibility for those CVCM [check valve condition monitoring plans that are not at the maximum intervals while also ensuring activities on individual valves are not deferred to the end of the group interval.

A similar comment has already been provided to chairman of the ASME OM, Subgroup - Check Valves for consideration.

23

Bases for Comment /

Background:

This condition was first imposed as part of final rulemaking dated July 17, 2017 and became effective on August 17, 2017 (Federal Register / Vol. 82, No. 136). This condition effectively implemented new requirements which were added to the 2017 Edition of OM, Appendix II, II-4000(b)(1)(e) that require distribution of Check Valve Condition Monitoring (CVCM) activities for each valve in a multi-valve group at approximately equal intervals across the interval for the group. The language in the 2017 Edition of OM and this condition are essentially the same.

While the goal for this condition and clarification in 2017 Edition of OM is appropriate, the actual language of these two documents have lead to unintended consequences. The statement, At least one of the identified activities for a valve group shall be performed on each valve of the group at approximately equal intervals not to exceed the maximum interval shown in Table II-4000-1 has resulted in significant burden for licensees to the revise their CVCM program plans for compliance. The requirement to distribute the CVCM activities across each valve at equal intervals is more prescriptive than necessary to ensure a licensee doesnt defer activities for all valves in a group to the end of the group interval.

Before this condition and OM change, most licensees performed CVCM activities on pairs of valves in a group or staggered the activities across the valve group interval in a manner that met the goal of distributing activities of multi-valve groups. However, the method of staggering activities did not meet the prescriptive language of this condition. As a result, the only way to comply with this condition and optimize testing is to split the group into smaller groups of valves or groups of one as permitted by II-2000(a). This is a significant burden on licensees and does not necessarily ensure a better distribution of activities.

Example:

Assume all activities for the group have not been completed such that interval extension is not allowed at the time the condition becomes effective.

Before Condition:

1 group of 4 valves where activities on 2 valves in the group are performed every other outage Group Outage 1 Outage 2 Outage 3 Outage 4 4 valves A, C B, D (A, B, C, D)

After Condition:

One group of four valves where activities on 1 valve in the group are performed every outage Group Outage 1 Outage 2 Outage 3 Outage 4 4 valves A C B D (A, B, C, D) 24

OR Two groups of Two valves where activities on one valve in the group are performed every other outage Group Outage 1 Outage 2 Outage 3 Outage 4 2 valves A B (A, B) 2 valves C D (C, D)

The example above demonstrates a case where a CVCM plan that met the original intent of OM to stagger activities yet still must be revised to comply with the condition. In addition, the example shows two different ways the CVCM program may be revised to order to comply with this condition. The last method shows how the revised CVCMP [check valve condition monitoring program] can comply with the condition without changing the schedule of activities.

The end result is that compliance with this condition imposed significant burden to revise CVCM plans with no increase in the level of safety.

NRC Response to Comments 002-01, 004-03, and 008-03: The NRC agrees in part and disagrees in part with these comments. The NRC agrees with the comments that the language in the 2017 Edition of the ASME Operation and Maintenance of Nuclear Power Plants, Division 1, OM Code: Section IST (OM Code) regarding approximately equal intervals for check valve condition monitoring in Appendix II to the ASME OM Code could be clearer. The NRC prepared the condition to match the overall improvement in the Appendix II provisions that were specified in the 2017 Edition of the ASME OM Code. ASME is currently preparing a modification to the ASME OM Code to clarify the language regarding approximately equal intervals for check valve condition monitoring. The NRC does not believe that it would be appropriate to modify the condition in advance of the completion of the consensus process underway in the ASME OM Code committees. In general, the NRC considers the language of approximately equal intervals to provide flexibility for licensees in establishing appropriate intervals for condition monitoring of their check valves under Appendix II to the ASME OM Code. The NRC will address any appropriate changes to this condition during the next rulemaking to update 10 CFR 50.55a, Codes and standards.

The NRC did not change the final rule as a result of these comments.

b. 10 CFR 50.55a(b)(3)(xi), OM Condition: Valve Position Indication Comment 001-01: This condition is applicable when implementing the 2012 or later editions of the ASME OM Code. This requirement stipulates that 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.

In the last rulemaking, 10 CFR 50.55a(b)(3)(xi) was updated to increase the scope of the OM condition to include valves covered in all of the mandatory appendices within the ASME OM Code. This change also allows other test methods and frequencies used in Subsection ISTC 25

and the mandatory appendices to verify obturator position on a test interval longer than every two years as prescribed by ISTC-3700.

Establishing a requirement to verify obturator position on every valve in the IST program with remote position indication can place a significant burden on the licensee to develop new test methods and procedures for valves that do not have supplemental means available, such as flow or pressure indication. In these cases, it may be necessary to purchase special equipment and deploy personnel to high radiological areas to verify obturator position on a frequency that may not add any increase in safety.

Recently, utilities have received NRC approval to use performance-based test methods, such as the 10 CFR 50 Appendix J test program, to verify obturator position. Performance-based test programs allow for valves to be tested at frequencies greater than every two years and require more frequent testing for poor performing valves. Other performance-based test programs include OM Code Cases OMN-23 and OMN-27, as well as the Check Valve Condition Monitoring program in Mandatory Appendix II, the inservice (diagnostic) test on motor-operated valves in Mandatory Appendix III, and the performance assessment test on air-operated valves in Mandatory Appendix IV.

The NRC expectations versus what is required in this condition is confusing. ISTC-3700 prescribes the position indication test be performed on a 24M frequency and the supplemental position verification test prescribed by this condition can be performed at a 24M frequency or other verification methods and frequencies. Is prior NRC approval required to deviate from the 24M frequency for obturator verification when using the performance-based Appendix J test program? The condition states that other verification methods and frequencies within Subsection ISTC and its mandatory appendices can be used to verify obturator position.

The 10 CFR 50 Appendix J test program is prescribed in Subsection ISTC, but the NRC has also stated in a recent public meeting that prior NRC approval would be needed to credit the verification methods and frequencies from the Appendix J program.

If the NRC currently believes that prior NRC approval is required to use performance-based test methods and frequencies for supplemental obturator position verification then the OM condition could be modified to allow performance-based test methods to verify obturator position while still maintaining reasonable assurance of the valve condition. The NRC staff should not be concerned with the performance history on specific valves within the scope of performance-based test programs since this type of test program requires more frequent testing for poor performance and valve degradation.

Performance-based test programs provide the reasonable assurance necessary to meet the intent of this OM condition on a frequency greater than every two years and would greatly reduce the burden on the licensee and the NRC staff.

It is recommended that the following wording be used to enhance the condition to provide greater flexibility in how licensees meet the intent of this OM condition:

When implementing paragraph ISTC-3700, Position Verification Testing, in the ASME OM Code, 2012 Edition through the latest edition of the ASME OM Code incorporated by reference in paragraph (a)(1)(iv) of this section, licensees must verify that valve operation is 26

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 the ASME OM Code and its performance based verification methods and frequencies. For valves not susceptible to stem-disk separation, the supplemental position verification testing specified in paragraph ISTC-3700 this condition may be performed based on guidance in Code Case OMN-28. on a 10-year interval where the licensee documents a justification, which is made available for NRC review, demonstrating that the stem-disk connection is not susceptible to separation based on the internal design and evaluation of the stem-disk connection using plant-specific and industry operating experience and vendor recommendations.

This change allows for the supplemental position obturator verification test to be credited by existing performance-based test methods and frequencies such as 10 CFR 50 Appendix J, Code Cases OMN-23 and OMN-27, and performance-based testing in Mandatory Appendices II, III and IV.

NRC Response to Comment 001-01: The NRC agrees with the suggestion to approve the use of ASME OM Code Case OMN-28, Alternative Valve Position Verification Approach to Satisfy ISTC-3700 for Valves Not Susceptible to Stem-Disk Separation, but disagrees with the remainder of this comment.

In the Federal Register notice dated March 26, 2021 (86 FR 16087), the NRC indicated it would consider an ASME Code Case that could provide increased schedule flexibility for position verification testing for incorporation by reference in the final rule. ASME has published that OM Code Case as OMN-28, and in the final rule, the NRC has replaced the proposed rule language allowing a 10-year interval for valve position indication testing for valves that have a stem-disk connection that is not susceptible to separation with a direct reference to Code Case OMN-28 in the final rule. The revised condition will allow licensees to extend the 2-year interval for valve position indication testing specified in ASME OM Code, Subsection ISTC, Inservice Testing of Valves in Water-Cooled Reactor Nuclear Power Plants, paragraph ISTC-3700, Position Verification Testing, to 12 years for valves with a stem-disk connection that is not susceptible to separation using the provisions in Code Case OMN-28. The NRC has incorporated this Code Case directly into 10 CFR 50.55a to make it available for immediate use.

The NRC disagrees with the comment suggesting that 10 CFR 50.55a(b)(3)(xi) be revised in the final rule to include a general reference to performance based verification methods with the intent to allow various methods for leakage testing intervals in Appendix J to 10 CFR Part 50, Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors, and other performance-based test methods and frequencies in the ASME OM Code and its various Code Cases. At this time, this revision is not necessary to implement the requirement, which merely emphasizes existing requirements in the ASME OM Code. The time and resources needed to develop appropriate requirements for performance-based methods would unduly delay the NRC making this edition of the ASME OM Code available for use by licensees.

The NRC may consider performance-based options for this valve position indication testing in a future rulemaking or if ASME incorporates such methods directly into ISTC-3700.

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In response to the specific question regarding the need for prior NRC authorization to deviate from the 24-month frequency for obturator verification when using the performance-based 10 CFR Part 50, Appendix J test program, the Appendix J test program can be referenced in an alternative request in describing the proposed alternative schedule for valve position verification. However, Appendix J addresses, in part, containment valve leakage, and does not provide justification for verifying the valve position indicating lights. Therefore, an alternative request in accordance with 10 CFR 50.55a(z) must be submitted if the Appendix J test program is proposed as part of an alternative to ISTC-3700 as supplemented by 10 CFR 50.55a(b)(3)(xi).

The NRC revised 10 CFR 50.55a(b)(3)(xi), replacing the verbiage allowing a 10-year interval for valve position indication testing for valves that have a stem-disk connection that is not susceptible to separation with a direct reference to the recently issued ASME Code Case OMN-28 in the final rule.

The NRC did not change the final rule as a result of this comment.

Comment 002-02: 10 CFR 50.55a(b)(3)(xi) OM Condition: Valve Position Indication should be removed.

Bases / Background ISTOG [inservice testing owners group] provided comments (ML16015A352) on the rulemaking in which this condition was first proposed on Friday September 18, 2015 (Federal Register /

Vol. 80, No. 181). Specifically, one of those comments stated, in part, ISTOG disagrees with proposed rulemaking and the rulemaking statement that changing the should to a shall in ISTC 3700 is not a new requirement but a clarification of the intent of the existing ASME OM Code.

The proposed rulemaking goes against the recognized authority of the OM Code interpretation and change processes. See the ASME OM Interpretation 12-01... Review of the NRCs Analysis of Public Comments (ML16130A531) shows there were numerous other public commenters stating this condition represented a new requirement contrary to NRCs assertion that it was merely a clarification.

In response to public comments, the final rulemaking was modified to defer the requirement to implement this condition until licensees perform the 120 month update of their IST program to incorporate the 2012 Edition or later of OM. This relaxation of implementation dates (from 30 days to up to 120 months) makes it clear that NRC recognized this condition would be a significant burden for licensees to implement.

Some licensees have started implementation of this condition and, as a result, they have had to submit requests for alternatives to address issues with implementation. In other cases, licensees are considering changing the valve design to remove the position indication as a more effective way of complying with this condition.

None of the actions described above (multiple public comments, deferral of implementation to next interval update, new requests for alternatives, and potential design changes to remove indication) would be necessary if this condition were just a clarification. This information clearly demonstrates this condition is a new requirement and was incorrectly evaluated against the backfit rule in the original rulemaking that imposed this condition.

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NRC Response to Comment 002-02: The NRC disagrees with this comment.

ASME OM Code, Subsection ISTC, paragraph ISTC-3700, as incorporated by reference in 10 CFR 50.55a, states the following:

Valves with remote position indicators shall be observed locally at least once every 2 years 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.

In 1995, the NRC staff emphasized the ASME OM Code requirement for valve position indication in Section 4.2.5 of the original issuance of NUREG-1482, Guidelines for Inservice Testing at Nuclear Power Plants, (ADAMS Accession No. ML20082T370). As discussed in NUREG-1482, Revision 3, issued July 2020), ASME OM Code, Subsection ISTC, paragraph ISTC-3700, allows flexibility to licensees in verifying that operation of valves with remote position indicators is accurately indicated. NUREG-1482 refers to various methods to verify valve operation, such as nonintrusive techniques, flow initiation or absence of flow, leak testing, and pressure testing.

Over many years, operating experience revealed that some licensees are not implementing ASME OM Code, Subsection ISTC, paragraph ISTC-3700, in a manner that provides reasonable assurance that the remote indicating lights for valves within the scope of their inservice testing (IST) program are accurately verifying the position of the valve obturator.

The NRC documented examples of this operating experience in Information Notice 2017-03, Anchor/Darling Double Disc Gate Valve Wedge Pin and Stem-Disc Separation Failures, dated June 15, 2017 (ADAMS Accession No. ML17153A053).

As a result of the operating experience, the NRC added paragraph (b)(3)(xi) in 10 CFR 50.55a to emphasize the requirements in Subsection ISTC, paragraph ISTC-3700, when incorporating by reference the 2012 Edition of the ASME OM Code into the NRC regulations in August 2017.

The Federal Register notice dated July 18, 2017 (82 FR 32934; 32950), for the final rule incorporating by reference the 2012 Edition of ASME OM Code into 10 CFR 50.55a states, in part, that the NRC is adding § 50.55a(b)(3)(xi) to emphasize the provisions in OM Code, 2012 Edition, Subsection ISTC-3700, Position Verification Testing, to verify that valve obturator position is accurately indicated.

During the proposed and final rule stages for the original 10 CFR 50.55a(b)(3)(xi), the NRC determined that the emphasis in 10 CFR 50.55a(b)(3)(xi) on the longstanding OM Code requirement for valve position indication does not represent a backfit. For example, the NRC stated in a response to public comments on the proposed rule (ADAMS Accession No. ML16130A531, pages 40-41) that this 10 CFR 50.55a condition is not a backfit because the condition does not alter the ASME OM Code requirements for valve position indication in ISTC-3700 as known for many years.

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The Federal Register notice for the 10 CFR 50.55a final rule for the 2012 Edition of the ASME OM Code (82 FR 32934; 32951) states, in part, that the NRC is requiring this condition for the implementation of the 2012 Edition of the OM Code for the 120-month IST interval in order to allow additional time for licensees to comply with this condition. The NRC discussed the additional time allowed in 10 CFR 50.55a(b)(3)(xi) by specifying the 2012 Edition at a public meeting during the public comment period for the proposed rule. In response to a public comment on the proposed rule (ADAMS Accession No. ML16130A531, pages 37-38), the staff declined to allow an additional 24 months beyond implementation of the 2012 Edition of the ASME OM Code to perform the valve position indication tests for licensees approaching their 120-month IST Program update. In the response to public comments, the NRC noted that licensees could request an alternative under 10 CFR 50.55a(z) if additional time was needed to implement 10 CFR 50.55a(b)(3)(xi).

The NRC does not consider this comment to impact the bases for the condition in 10 CFR 50.55a(b)(3)(xi) to supplement the valve position indication requirements in the ASME OM Code.

The NRC did not change the rule as a result of this comment.

Comment 002-03: If the first comment above is not accepted, then ISTOG would like to thank NRC for adding language in this condition to address those valves that are non-susceptible to stem-disc separation. This is an important change that will benefit the industry by reducing burden of testing valves that are shown to have little to no history of stem-disc separation and providing more focus on those valves that warrant additional attention.

Recently approved ASME OM Code Case OMN-28 provides a structured approach for position indication testing of non-susceptible valves. It provides guidance for determining the scope of valves, describes testing requirements (methods and frequency), as well as necessary corrective actions upon failure of testing.

Recommend NRC endorse the use of Code Case OMN-28 in this rulemaking in lieu of the proposed new language of this condition.

NRC Response to Comment 002-03: The NRC agrees with this comment. In the Federal Register notice dated March 26, 2021 (86 FR 16087), the NRC indicated it would consider an ASME Code Case that could provide increased schedule flexibility for position verification testing for incorporation by reference in the final rule. The ASME has published that OM Code Case as OMN-28, and in the final rule, the NRC has replaced the proposed rule language allowing a 10-year interval for valve position indication testing for valves that have a stem-disk connection that is not susceptible to separation with a direct reference to ASME OM Code Case OMN-28.

The NRC did not change the final rule as a result of this comment.

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Comment 002-04: If the first comment above is not accepted, then ISTOG recommends this condition be revised to clarify the starting point for this condition or the time frame implementation must be completed.

Bases / Background ISTOG members have unanimously interpreted the condition language which states, When implementing paragraph ISTC-3700, Position Verification Testing, in the ASME OM Code, 2012 Edition through the latest edition to mean the implementation clock starts on the first day of the IST interval that requires compliance with the 2012 Edition or later edition of OM.

Further, they believed there was two years from the start date of the interval to be in full compliance with the condition.

This interpretation is based on the principle that requirements imposed based on an interval start date could not or did not extend back into the previous interval where the 2012 Edition or later edition was not applicable. In addition, the ISTOG members also recognize that in many cases, the supplemental verification of both open and closed valve positions may not be able to be performed concurrently. Also, it also may not be possible to perform concurrent with the ISTC-3700 required local observation of stem travel. The provisions of ISTC-3700 clearly state that when using supplemental observations such as flow meters, the observations need not be concurrent.

NRC Response to Comment 002-04: The NRC disagrees that revision of 10 CFR 50.55a(b)(3)(xi) is needed to clarify the start date for the condition upon implementation of the 2012 or later Edition of the ASME OM Code. The rule specifies that when the ISTC-3700 test is conducted following implementation of the 2012 or later Edition of the ASME OM Code, that test will be supplemented to provide reasonable assurance that the indicating lights are accurately monitoring the position of the valve obturator. The condition thus applies at the time the test is performed during the interval implementing the 2012 or later edition, not at some interval distinct from the timing of the ISTC-3700 test and unrelated to the IST intervals start date. The NRC takes no position on the principle described in the comment, but the NRC discussed the start date extensively during the final rulemaking for 10 CFR 50.55a(b)(3)(xi).

The Federal Register notice for the 10 CFR 50.55a final rule for the 2012 Edition of the ASME OM Code (82 FR 32934; 32951) states, in part, that the NRC is requiring this condition for the implementation of the 2012 Edition of the OM Code for the 120-month IST interval in order to allow additional time for licensees to comply with this condition. The additional time allowed in 10 CFR 50.55a(b)(3)(xi) by specifying the 2012 Edition was discussed at a public meeting during the public comment period for the proposed rule. In response to a public comment on the proposed rule (ADAMS Accession No. ML16130A531; pages 37-38), the staff declined to allow an additional 24 months beyond implementation of the 2012 Edition of the ASME OM Code to perform the valve position indication tests for licensees approaching their 120-month IST Program update. In the response to public comments, the NRC noted that licensees could request an alternative under 10 CFR 50.55a(z) if additional time was needed to implement 10 CFR 50.55a(b)(3)(xi). The NRC reaffirmed those points in the Federal Register notice for the final rule.

With respect to the statement in ISTC-3700 that the observations need not be concurrent, the NRC agrees that this ISTC-3700 language is confusing because the purpose of observing 31

such parameters as flow is to provide reasonable assurance that the indicating lights are accurately monitoring the valve obturator position. Therefore, the lights and supplemental observations need to be monitored together to demonstrate that the lights are performing properly. Although ISTC-3700 is not clear, this ASME OM Code paragraph allows flexibility regarding when someone is physically located at the valve to monitor stem travel and when someone is monitoring flow at another location. Further, the NRC considers the discussion of nonconcurrent testing in ISTC-3700 to also apply to the open and close function of each valve.

For example, licensees might find it more convenient to verify that the remote indicating light for the open function is operating properly on a different day than the remote indicating light for the close function. The ASME OM Code allows nonconcurrent testing for both the open and close function as long as the 2-year test frequency required by IST-3700 is satisfied for each stroke direction.

The NRC did not change the final rule as a result of this comment.

Comment 004-04A: NEI recommends considering the following as part of the revision to

§ 50.55a(b)(3)(xi):

Licensees must verify that valve operation is accurately indicated by supplementing valve position indicating lights with other indications such as flow meters or other suitable instrumentation during performance of remote position indication testing by ISTC-3700 to provide assurance of proper obturator position for valves with remote position indication.

ISTC-3700 requires remote position indication testing every 2 years and the (b)(3)(xi) condition applies when the remote position indication test is performed (2 years from the previous remote position indication test). Supplemental position verification must be performed in conjunction with but not concurrent with remote position indication testing.

Supplemental position verification for motor-operated valves (MOVs) within the scope of Mandatory Appendix III must be performed in conjunction with but not concurrent with III-3300(e) remote position indication testing. Supplemental position verification can be observed using performance-based verification methods and frequencies within the scope of the ASME OM Code.

Supplemental position verification observations are not required for passive valves.

Supplemental position verification observations are required to start during performance of the first remote position indication test following licensee implementation of the ASME OM Code, 2012 Edition through the latest edition of the ASME OM Code incorporated by reference in paragraph (a)(1)(iv) of this section. If plant conditions prohibit the initial supplemental position verification within the 2-year period of the previously performed remote position indication test, then it shall be done at the next opportunity but prior to 24 months from the implementation of ASME OM Code, 2012 Edition.

Comments:

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1. There were no changes made to the condition to clarify implementation of Supplemental Position Indication (SPI). Changes are required to eliminate interpretation differences between the NRC and Licensees:

a. Utilize modified wording that was presented by the NRC during public meeting:

ISTC-3700 requires valve position verification testing every 2 years and the (b)(3)(xi) condition applies when the ISTC-3700 test is performed (2 years from the previous

[ISTC-3700] test).

b. Clarify SPI is required to be performed in conjunction with (i.e., same surveillance) but not required to be concurrent with (i.e., not at the same time as) Position Verification testing following adoption of the ASME OM Code, 2012 Edition though the latest edition of the ASME OM Code.

c. Clarify SPI required surveillance due date for MOVs in Appendix III as Position Verification testing shifted from 2Y to the Appendix III inservice testing frequency. For example, is the SPI test due date X years from the previous Position Verification test or X years from the previous diagnostic test (where X years represents the Appendix III inservice test interval).

d. Clarify required surveillance due date when implementing extended frequency testing for valves not susceptible to stem disc separation. For example, can SPI be performed 10Y from the last performance of a Position Verification test prior to implementing the latest edition of the Code?

e. Confirm that MOV Position Verification testing, and therefore SPI testing, will follow the extended inservice test interval per OMN-26 application. OMN-26 provides an alternate inservice test interval based on individual valve Risk and Margin.

The alternate interval is applicable to III-3300 Inservice Test including III-3300(e) remote position indication and therefore SPI.

NRC Response to Comment 004-04A: The NRC disagrees with the proposed rewording because (1) it is not clearer than the wording of the condition as proposed, (2) it introduces new issues that could prohibit the use of options that are currently available to licensees, and (3) it is based on positions, about supplemental valve indication, with which the NRC disagrees.

The NRC has the following response to each proposed sentence revision for 10 CFR 50.55a(b)(3)(xi):

(1) The NRC notes that the first sentence is similar to the current wording of 10 CFR 50.55a(b)(3)(xi). However, it suggests that the valve position verification methods and frequencies in the ASME OM Code appendices (such as Appendix III for MOVs and Appendix IV for air-operated valves) are no longer acceptable.

(2) The NRC agrees that the second proposed sentence appears to be consistent with 10 CFR 50.55a(b)(3)(xi).

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(3) The third proposed sentence incorrectly implies that the supplemental valve position indication requirement in 10 CFR 50.55a(b)(3)(xi) is a separate test from the valve position indication requirement in ASME OM Code, Subsection ISTC, paragraph ISTC-3700. With respect to the statement in ISTC-3700 that the observations need not be concurrent, the NRC agrees that this ISTC-3700 language is confusing because the purpose of observing such parameters as flow is to provide reasonable assurance that the indicating lights are accurately monitoring the valve obturator position.

Therefore, the lights and supplemental observations need to be monitored together to demonstrate that the lights are performing properly. Although ISTC-3700 is not clear, this ASME OM Code paragraph allows flexibility regarding when someone is physically located at the valve to monitor stem travel and when someone is monitoring flow at another location. Further, the NRC considers the discussion of nonconcurrent testing in ISTC-3700 to also apply to the open and close function of each valve. For example, licensees might find it more convenient to verify that the remote indicating light for the open function is operating properly on a different day than the remote indicating light for the close function. The ASME OM Code allows nonconcurrent testing for both the open and close function as long as the 2-year test frequency required by IST-3700 is satisfied for each stroke direction.

(4) The fourth proposed sentence has issues similar to the third sentence, in that the supplement position indication requirement applies when conducting the valve position verification testing required by ISTC-3700. They are not separate tests.

(5) With respect to the fifth proposed sentence, the NRC disagrees with the comment suggesting that 10 CFR 50.55a(b)(3)(xi) be revised in the final rule to include a general reference to performance based verification methods with the intent to allow various methods for leakage testing intervals in 10 CFR Part 50, Appendix J, and other performance-based test methods and frequencies in the ASME OM Code and its various Code Cases. At this time, this revision is not necessary to implement the requirement, which merely emphasizes existing requirements in the ASME OM Code. The time and resources needed to develop appropriate requirements for performance-based methods would unduly delay the NRC making this edition of the ASME OM Code available for use by licensees. The NRC may consider performance-based options for this valve position indication testing in a future rulemaking or if ASME incorporates such methods directly into ISTC-3700.

(6) The NRC disagrees with the suggestion in the sixth proposed sentence to remove passive valves from supplemental position indication requirements in 10 CFR 50.55a(b)(3)(xi) as part of this rulemaking. The purpose of the supplemental position indication requirement in 10 CFR 50.55a(b)(3)(xi) is to provide assurance that the remote indicating lights properly indicate the position of the valve obturator.

The proper position of the valve obturator is important for both active and passive valves.

(7) The NRC agrees with the proposition of the seventh proposed sentence and considers this proposed sentence to be consistent with the requirement in 10 CFR 50.55a(b)(3)(xi).

However, the NRC does not agree further clarification of the requirement is necessary in light of the NRCs extensive discussions in multiple rulemakings and public meetings.

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(8) With respect to the eighth proposed sentence, the NRC has evaluated the comment requesting that 10 CFR 50.55a(b)(3)(xi) allow a licensee to determine that if plant conditions prohibit the initial supplemental position verification within the 2-year period of the previously performed remote position indication test, then it shall be performed at the next opportunity but prior to 24 months from the implementation of ASME OM Code, 2012 Edition. The NRC has modified 10 CFR 50.55a(b)(3) (xi) to allow a licensee to extend the schedule for ISTC-3700 as supplemented by 10 CFR 50.55a(b)(3)(xi) where plant conditions prohibit the initial supplemental verification within the 2-year time period of the previously performed ISTC-3700 test where justification is available on-site for NRC review.

Overall, the extensive revisions to 10 CFR 50.55a(b)(3)(xi) suggested in this comment exceed the intended scope of the condition, which only emphasizes existing requirements in the Code.

For example, the suggestions to remove valve position indication requirements for passive valves and stop check valves are more appropriately addressed by the ASME OM Code committees. The NRC included 10 CFR 50.55a(b)(3)(xi) to clarify the requirements for valve position indication only after 20 years of unsuccessful efforts by the ASME OM Code committees to clarify the existing requirements in ISTC-3700. Most of the revisions suggested by the comment involve substantive issues that should be extensively developed through other processes, including an opportunity for comment, that would unnecessarily delay the present rulemaking. The NRC staff welcomes the opportunity to consider these suggestions through the ASME OM Code committee process.

The NRC did not change the final rule as a result of this comment.

Comment 004-04B: There were no changes made to the condition to clarify implementation of Supplemental Position Indication (SPI). Changes are required to eliminate interpretation differences between the NRC and Licensees:

a. Utilize modified wording that was presented by the NRC during public meeting:

ISTC-3700 requires valve position verification testing every 2 years and the (b)(3)(xi) condition applies when the ISTC-3700 test is performed (2 years from the previous

[ISTC-3700] test).

b. Clarify SPI is required to be performed in conjunction with (i.e., same surveillance) but not required to be concurrent with (i.e., not at the same time as) Position Verification testing following adoption of the ASME OM Code, 2012 Edition though the latest edition of the ASME OM Code.

c. Clarify SPI required surveillance due date for MOVs in Appendix III as Position Verification testing shifted from 2Y to the Appendix III inservice testing frequency. For example, is the SPI test due date X years from the previous Position Verification test or X years from the previous diagnostic test (where X years represents the Appendix III inservice test interval).

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d. Clarify required surveillance due date when implementing extended frequency testing for valves not susceptible to stem disc separation. For example, can SPI be performed 10Y from the last performance of a Position Verification test prior to implementing the latest edition of the Code?

e. Confirm that MOV Position Verification testing, and therefore SPI testing, will follow the extended inservice test interval per OMN-26 application. OMN-26 provides an alternate inservice test interval based on individual valve Risk and Margin.

The alternate interval is applicable to III-3300 Inservice Test including III-3300(e) remote position indication and therefore SPI.

NRC Response to Comment 004-04B: The NRC agrees that no changes were made to the condition in terms of its implementation. The NRC disagrees that changes are required to eliminate interpretation differences between the NRC and licensees. The Federal Register notice for the 10 CFR 50.55a final rule for the 2012 Edition of the ASME OM Code (82 FR 32934; 32951) states, in part, that the NRC is requiring this condition for the implementation of the 2012 Edition of the OM Code for the 120-month IST interval in order to allow additional time for licensees to comply with this condition. The additional time allowed in 10 CFR 50.55a(b)(3)(xi) by specifying the 2012 Edition was discussed at a public meeting during the public comment period for the proposed rule. In response to a public comment on the proposed rule (ADAMS Accession No. ML16130A531, pages 37-38), the staff declined to allow an additional 24 months beyond implementation of the 2012 Edition of the ASME OM Code to perform the valve position indication tests for licensees approaching their 120-month IST Program update. In the response to public comments, the NRC noted that licensees could request an alternative under 10 CFR 50.55a(z) if additional time was needed to implement 10 CFR 50.55a(b)(3)(xi).

With respect to item a. of the comment, the NRC agrees that the wording presented by the NRC during the public meeting on June 14, 2021, that ISTC-3700 requires valve position verification testing every 2 years and the 10 CFR 50.55a(b)(3)(xi) condition applies when the ISTC-3700 test is performed (2 years from the previous ISTC-3700 test). The condition does not change the schedule for ISTC-3700 testing.

With respect to item b. of the comment, the NRC disagrees with the suggestion. The condition in 10 CFR 50.55a(b)(3)(xi) supplements the performance of the ISTC-3700 testing.

The condition does not create a separate test.

The NRC does not agree with item c. of the comment, which suggests modifying the condition to state that the SPI required surveillance due date for MOVs in Appendix III as position verification testing shifted from 2 years to the Appendix III inservice testing frequency.

The condition merely emphasizes the existing requirement and is not intended to change it.

With respect to item d. of the comment, the NRC disagrees with the suggestion to modify the condition to specify the required surveillance due date when implementing extended frequency testing for valves not susceptible to stem-disk separation. As mentioned, when the NRC first issued the condition, it merely emphasized existing ASME OM Code requirements applicable when performing the ISTC-3700 testing. The condition for supplemental position indication is applicable to any licensee implementing the 2012 Edition or later of the ASME OM 36

Code. The supplemental provisions would apply when performing the ISTC-3700 testing required by those ASME OM Code editions.

With respect to item e. of the comment, the NRC agrees with the comment that MOV position verification testing, and therefore SPI testing, may follow the extended inservice test interval allowed by application of ASME OM Code Case OMN-26.

The NRC did not change the final rule as a result of this comment.

Comment 004-04C: Passive Valves - Sites are performing modification where possible or removing valves from the IST program to eliminate the need to do SPI testing. The condition should be changed to eliminate SPI for passive valves. If this change is not agreeable, then the condition should be changed to only perform SPI testing of passive valves in the valves normal passive position. Since these valves are not required to change position to perform their safety function, SPI verification and especially verification in both positions does not provide any benefit to safety.

a. As stated in EPRI 3002019621: The NRC monitors current industry-average nuclear power plant equipment performance on its website Industry Average Parameter Estimates.

This website currently contains component reliability data through 2015, based on data from INPO. The Component Reliability Data Sheets on this website summarize failure data for various component types, including valves. The failure data is categorized by failure mode (e.g., failure to open), and the details of the failure (such as whether it was due to a stem-to-disk separation) are not included. This data is used by the NRC as input to their Standardized Plant Analysis Risk models and by nuclear plants in the Probabilistic Risk Assessment (PRA) models and provides a reference point against which the stem-to-disk failure data summarized later in this section can be compared.

This data should have identified any concerns with stem-to-disc failure, however, the NRCs SPAR modeling and industry use for PRA does not appear to identify any industry concerns of stem-to-disc failures. This would provide more documented data that passive valves and Non-susceptible stem-to-disk connections should be exempted for SPI.

NRC Response to Comment 004-04C: The NRC disagrees with the suggestion to remove passive valves from supplemental position indication requirements in 10 CFR 50.55a(b)(3)(xi) as part of this rulemaking. The purpose of the supplemental position indication requirement in 10 CFR 50.55a(b)(3)(xi) is to provide assurance that the remote indicating lights properly indicate the position of the valve obturator. The proper position of the valve obturator is important for both active and passive valves. With respect to the referenced EPRI report, the NRC has documented operating experience with the failure of valve stem-disk connections, such as in NRC Information Notice 2012-14, Motor-Operated Valve Inoperable due to Stem-Disc Separation, dated July 24, 2012 (ADAMS Accession No. ML12150A046) and Information Notice 2017-03, Anchor/Darling Double Disc Gate Valve Wedge Pin and Stem-Disc Separation Failures, dated June 15, 2017 (ADAMS Accession No. ML17153A053).

The NRC did not change the final rule as a result of this comment.

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Comment 004-04D: Endorse ASME Code Case OMN-28s 12-year extended frequency for non-susceptible valves as approved or by name, versus the proposed NRC extended frequency wording of 10 years. OMN-28 provides additional guidance compared to the NRC proposed wording and will ensure there are no interpretation issues that would require sites to prepare additional relief.

NRC Response to Comment 004-04D: The NRC agrees that approval of ASME OM Code Case OMN-28 is an improvement to the summarized requirement proposed for inclusion in 10 CFR 50.55a(b)(3)(xi).

The NRC revised the condition to approve Code Case OMN-28 directly. The Federal Register notice for the proposed rule stated that the NRC was aware that the ASME OM Code committees were considering a Code Case that would allow up to 12 years as the maximum interval for valve position verification testing, and that if that Code Case was issued prior to publication of the final rule, the NRC might approve that Code Case in the final rule (86 FR 16087; 16096). Although the Code Case number was not yet assigned at the time when the NRC was preparing the proposed rule, it was issued in March 2021 as OM Code Case OMN-28.

There was no change to the final rule as a result of this comment.

Comment 004-04E: The proposed rulemaking has reduced the burden of testing valves not susceptible to stem-disc separation by allowing the test frequency to occur at a 10-year interval based on a sites justification. However, if a valve is determined to not be susceptible to stem-disc separation, then NEI recommends that SPI testing is not required at all and Position Verification testing (excluding SPI) continue once every 2 years. If a valve is non-susceptible, then the burden of adding additional testing to verify stem-to-disc integrity doesnt add value or benefit to safety.

NRC Response to Comment 004-04E: The NRC disagrees with the suggestion to remove supplemental position indication for valves determined to not be susceptible to stem-disk separation. The intent of ISTC-3700 is to verify that the remote indicating lights are accurate.

Reliance only on the lights to verify that the lights are accurate is not appropriate to meet the intent of ISTC-3700. In addition, there are more potential causes of the remote indicating lights being inaccurate beyond stem-disk separation (such as the limit switch gearing becoming out of synchronization with the stem travel). Therefore, supplemental position indication is appropriate for valves with a stem-disk connection that is not susceptible to separation on at least the extended interval allowed by ASME OM Code Case OMN-28.

The NRC did not change the final rule as a result of this comment.

Comment 004-04F: Due to the detail provided in the EPRI Technical Report for evaluation of valve susceptibility, Susceptibility of Valve Applications to Failure of the Stem-to-disk Connection, it is recommended that it be referenced as an acceptable method for determination of valve susceptibility in support of implementing the proposed rulemaking or OMN-28.

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NRC Response to Comment 004-04F: The NRC agrees that the referenced EPRI report could be useful to licensees implementing ASME OM Code Case OMN-28. The NRC notes that neither 10 CFR 50.55a(b)(3)(xi) nor ISTC-3700 limit what indications licensees are permitted to use to supplement valve position indicating lights. The NRC staff plans to review the EPRI report soon and may provide guidance on its use by licensees in a separate document.

The NRC did not change the final rule as a result of this comment.

Comment 004-04G: The current condition states that SPI must be performed on valves with indicating lights that are within the scope of Subsection ISTC including applicable mandatory appendices. The condition also states that SPI can be performed by using other verification methods and frequencies within Subsection ISTC and applicable Mandatory Appendices that are performed at intervals greater than every two years. The Local Leak Rate Testing (LLRT) prescribed by 10 CFR 50 Appendix J programs is also prescribed by Subsection ISTC. Based on the condition wording, licensees believe that prior NRC approval is not required for SPI testing to be performed on the LLRT frequency because it is prescribed by Subsection ISTC.

However, to ensure alignment on this interpretation, and prevent additional burden, the condition should clarify that it is permitted to use NRC-approved seat leakage performance-based frequencies for SPI, such as 10 CFR 50 Appendix J, approved performance-based Code Cases (OMN-23 and OMN-27), or NRC approved site-specific relief requests, without having to seek approval of more relief requests which would be redundant to already approved alternatives.

NRC Response to Comment 004-04G: The NRC disagrees with the comment suggesting that 10 CFR 50.55a(b)(3)(xi) be revised in the final rule to include a general reference to performance based verification methods with the intent to allow various methods for leakage testing intervals in Appendix J to 10 CFR Part 50 and other performance-based test methods and frequencies in the ASME OM Code and its various Code Cases. At this time, this revision is not necessary to implement the requirement, which merely emphasizes existing requirements in the ASME OM Code. The time and resources needed to develop appropriate requirements for performance-based methods would unduly delay the NRC making this edition of the ASME OM Code available for use by licensees. The NRC may consider performance-based options for this valve position indication testing in a future rulemaking or if ASME incorporates such methods directly into ISTC-3700.

The NRC did not change the final rule as a result of this comment.

Comment 004-04H: Stop check valves should be excluded from SPI. Per valve design, the disc is not connected to the stem. In this case, position indication is for the valve stem only and not the check valve disc.

NRC Response to Comment 004-04H: The NRC disagrees with the suggestion to remove stop check valves from supplemental position indication requirements in 10 CFR 50.55a(b)(3)(xi) as part of this rulemaking. The time and resources needed to develop appropriate requirements for remote position verification of stop check valves would unduly delay the NRC making this edition of the Code available for use by licensees. The NRC may 39

consider removing remote position indication testing for stop check valves in a future rulemaking if not addressed by ASME directly in ISTC-3700.

The NRC did not change the final rule as a result of this comment.

Comment 006-03: Exelon requests further clarification concerning Supplemental Position Indication (SPI) implementation timeline and test due dates as no changes were made to the Condition to eliminate interpretation differences between the NRC and Licensees.

Additionally, there should be clarification of SPI being required to be performed in conjunction with, but not required to be concurrent with, ISTC-3700 testing following adoption of the ASME OM Code, 2012 Edition, through the latest edition of the ASME OM Code.

NRC Response to Comment 006-03: The NRC disagrees that revision of 10 CFR 50.55a(b)(3)(xi) is needed to clarify the start date for the condition. The start date was discussed extensively during the final rulemaking for 10 CFR 50.55a(b)(3)(xi). The Federal Register notice for the 10 CFR 50.55a final rule for the 2012 Edition of the ASME OM Code states, in part, that the NRC is requiring this condition for the implementation of the 2012 Edition of the OM Code for the 120-month IST interval in order to allow additional time for licensees to comply with this condition (82 FR 32951). The additional time allowed in 10 CFR 50.55a(b)(3)(xi) by specifying the 2012 Edition was discussed at a public meeting during the public comment period for the proposed rule. In response to a public comment on the proposed rule (ADAMS Accession No. ML16130A531, pages 37-38), the NRC declined to allow an additional 24 months beyond implementation of the 2012 Edition of the ASME OM Code to perform the valve position indication tests for licensees approaching their 120-month IST Program update. In the response to public comments, the NRC noted that licensees could request an alternative under 10 CFR 50.55a(z) if additional time was needed to implement 10 CFR 50.55a(b)(3)(xi). The NRC has restated those discussions in the Federal Register notice for the final rule. The NRC also disagrees with the implication in the comment that 10 CFR 50.55a(b)(3)(xi) represents new testing requirements. The supplemental requirements in 10 CFR 50.55a(b)(3)(xi) emphasize the requirements in ASME OM Code, Subsection ISTC, paragraph ISC-3700, to verify that the remote valve position indicating lights accurately indicate the position of the valve obturator.

The NRC did not change the final rule as a result of this comment.

Comment 006-04: Exelon requests further clarification of the SPI required testing due date for motor operated valves (MOVs) in Appendix III as the ISTC-3700 testing has shifted from 2 years to the Appendix III Inservice Testing (IST) frequency.

NRC Response to Comment 006-04: The NRC disagrees with this comment that clarification is needed regarding the reference to ASME OM Code, Appendix III, Preservice and Inservice Testing of Active Electric Motor-Operated Valve Assemblies in Water-Cooled Reactor Nuclear Power Plants, in paragraph ISTC-3700 for verification of valve position indication for MOVs.

The regulation at 10 CFR 50.55a(b)(3)(xi) requires that supplemental valve verification be performed whenever ISTC-3700 testing is performed. The schedule for ISTC-3700 testing is 40

specified by the licensees code of record, any applicable Code Cases, or authorized alternatives.

The NRC did not change the final rule as a result of this comment.

Comment 006-05: Exelon suggests eliminating the supplemental verification requirement for passive valves or at a minimum only require it in the required valve position. Sites are performing modification where possible or removing valves from the IST program to eliminate the need to do supplemental testing.

NRC Response to Comment 006-05: The NRC disagrees with this comment. The purpose of the supplemental position indication requirement in 10 CFR 50.55a(b)(3)(xi) is to provide assurance that the remote indicating lights properly indicate the position of the valve obturator.

The proper position of the valve obturator is important for both active and passive valves.

The NRC may consider the suggestion in this comment during a future 10 CFR 50.55a rulemaking.

The NRC did not change the final rule as a result of this comment.

Comment 006-06: Exelon is requesting further clarification regarding why supplemental verification testing needs to be performed for valves that are determined to be not-susceptible to stem-disc separation.

NRC Response to Comment 006-06: The supplemental requirements in 10 CFR 50.55a(b)(3)(xi) to emphasize the ASME OM Code requirements for valve position indication are intended to provide reasonable assurance that the remote position indicating lights accurately indicate the position of the valve obturator. The ASME OM Code requirement to periodically verify that remote position indicating lights are accurate remains necessary for valves that change position to perform a safety function (active valves) or remain in their position to perform a safety function (passive valves). The final rule approves the use of ASME OM Code Case OMN-28, which will allow licensees to extend the verification interval for valves with a stem-disk connection that is not susceptible to separation, but completely eliminating this safety requirement is not appropriate based on currently available information.

The NRC did not change the final rule as a result of this comment.

Comment 006-07: Exelon suggests that the NRC consider endorsing ASME Code Case OMN-28 (instead of the proposed NRC revision) for valves that are not susceptible to stem-disc separation "similar to what was done with OMN-20."

NRC Response to Comment 006-07: The NRC agrees with this comment. The NRC replaced the proposed rule language allowing a 10-year interval for valve position indication testing for valves that have a stem-disk connection that is not susceptible to separation with a direct reference to the recently issued ASME OM Code Case OMN-28.

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The NRC did not change the final rule as a result of this comment.

Comment 006-08: Exelon requests further clarification concerning the required testing due date when implementing the conditions for valves not susceptible to stem-disc separation or OMN-28. For example, can SPI be performed 10 years from the last performance of an ISTC-3700 test prior to implementing the latest edition of the Code?

NRC Response to Comment 006-08: The NRC replaced the proposed rule language allowing a 10-year interval for valve position indication testing for valves that have a stem-disk connection that is not susceptible to separation with a direct reference to the recently issued ASME OM Code Case OMN-28. When Code Case OMN-28 is applied, the valve position indication testing will be required to be performed 12 years after the previous ISTC-3700 valve position indication test.

The NRC did not change the final rule as a result of this comment.

Comment 006-09: Exelon suggests adding a reference to the EPRI document as acceptable method for determination of valve stem-disc separation susceptibility.

NRC Response to Comment 006-09: The NRC agrees that the referenced EPRI report could be useful to licensees implementing ASME OM Code Case OMN-28. The NRC staff plans to review the EPRI report soon and may provide guidance on its use by licensees in a separate document. The NRC notes that neither 10 CFR 50.55a(b)(3)(xi) nor ISTC-3700 limits what indications licensees are permitted to use to supplement valve position indicating lights.

The NRC did not change the final rule as a result of this comment.

Comment 006-10: Exelon suggests adding an approval to utilize NRC-approved, performance-based, frequencies for SPI such as Appendix J or other approved performance-based Code Cases or site-specific relief requests.

Suggested wording to address start of SPI testing (draft):

Licensees must verify that valve operation is accurately indicated by supplementing valve position indicating lights with other indications such as flow meters or other suitable instrumentation during performance of ISTC-3700 testing to provide assurance of proper obturator position for valves with remote position indication. Supplemental verification must be performed in conjunction with, but not concurrent with ISTC-3700, "Position Verification Testing." Supplemental verification for MOVs within the scope of Mandatory Appendix III must be performed in conjunction with but not concurrent with III-3300(e) position verification. Supplemental testing is required to start during performance of the first Position Verification Test following licensee implementation of the ASME OM Code, 2012 Edition, through the latest edition of the ASME OM Code incorporated by reference in paragraph (a)(1)(iv) of this section.

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NRC Response to Comment 006-10: The NRC disagrees with the comment suggesting that 10 CFR 50.55a(b)(3)(xi) be revised in the final rule to include a general reference to performance based verification methods with the intent to allow various methods for leakage testing intervals in 10 CFR Part 50, Appendix J, and other performance-based test methods and frequencies in the ASME OM Code and its various Code Cases. At this time, this revision is not necessary to implement the requirement, which merely emphasizes existing requirements in the ASME OM Code. The time and resources needed to develop appropriate requirements for performance-based methods would unduly delay the NRC making this edition of the ASME OM Code available for use by licensees. The NRC may consider performance-based options for this valve position indication testing in a future rulemaking or if ASME incorporates such methods directly into ISTC-3700.

The NRC did not change the final rule as a result of this comment.

Comment 008-04: TVA acknowledges that the proposed change to condition (b)(3)(xi) provides some relief from a burdensome requirement imposed by the rule. However, in collaboration across the industry, a detailed alternative to compliance with the condition was created and approved in ASME OM Code Case OMN-28. Therefore, it is recommended that the proposed change to the CFR be replaced as follows: For valves not susceptible to stem-disk separation, ASME OM Code Case OMN-28 may be used to satisfy the valve position verification requirements in ASME OM Code, Subsection ISTC, paragraph ISTC3700.

NRC Response to Comment 008-04: The NRC agrees with this comment in general.

The NRC replaced the proposed rule language allowing a 10-year interval for valve position indication testing for valves that have a stem-disk connection that is not susceptible to separation with a direct reference to the recently issued ASME OM Code Case OMN-28.

The NRC did not change the final rule as a result of this comment.

Comment 008-05: OM Condition (b)(3)(xi) provides a requirement for plants in the process of an interval update from any edition older than the 2012 ASME OM Code. There has been confusion regarding the initial test requirement and initial performance date. Given the potentially significant burden imposed by this new test requirement, additional guidance should be provided for the initial implementation timeframe to minimize confusion.

While Condition (b)(3)(xi) is based upon a test currently contained in the Code, the modification of the existing test is such that an entirely new test requirement is being created through this condition. The NRC is proposing a risk-based modification to the implementation with the proposed change. Specifying an initial test date of no later than 2 years (ISTC-3700 Frequency) from the start of the interval matches the historical precedent for a new requirement.

TVA recommends that NRC specify an initial test date of no later than 2 years (ISTC-3700 Frequency) from the start of the interval for which the newer Code applies.

NRC Response to Comment 008-05: The NRC disagrees with this comment that 10 CFR 50.55a(b)(3)(xi) represents a new test requirement. The supplemental condition in 10 CFR 50.55a(b)(3)(xi) emphasizes the requirements in ASME OM Code, Subsection ISTC, paragraph 43

ISC-3700, to verify that the remote valve position indicating lights accurately indicate the position of the valve obturator. The supplemental condition in 10 CFR 50.55a(b)(3)(xi) and the applicable start date were discussed extensively during the original rulemaking for 10 CFR 50.55a(b)(3)(xi). The NRC has restated those discussions in the Federal Register notice for the final rule. The NRC also addressed this question in Information Notice 2021-01, Lessons Learned from U.S. Nuclear Regulatory Commission Inspections of Design-Basis Capability of Power-Operated Valves at Nuclear Power Plants, dated May 6, 2021.

The NRC did not change the final rule as a result of this comment.

c. 10 CFR 50.55a(f)(4), Inservice Testing Standards Requirement for Operating Plants Comment 001-02: The proposed rulemaking currently deletes the phrase ...without requesting relief under paragraph (f)(5) of this section or alternatives under paragraph (z) of this section.

This deletion implies that there may be some cases where non-Code Class components will require prior NRC approval to deviate from ASME OM Code requirements. Licensees currently have justifications for non-Code Class components justifying that Code deviations demonstrate an acceptable level of quality and safety, or that implementing the Code provisions would result in a hardship or unusual difficulty without a compensating increase in the level of quality and safety. The NRC staff will need to provide examples of when prior NRC approval would be required and when prior NRC approval would not be required prior to implementing this change in order for licensees to determine if the currently implemented justifications need prior NRC approval and allow the NRC staff adequate time to review any needed requested alternatives.

Comment 002-05: The proposed rulemaking removes a portion of sentence which states, without requesting relief under paragraph (f)(5) of this section or alternatives under paragraph (z) of this section...

Recommend this phrase is retained in the final rule. This language is necessary to clarify that formal submittals of requests for relief or alternatives are not required for augmented IST program related components. As an option, this language could be relocated to (f)(6)(ii) along with the subsequent sentence regarding the use of an augmented IST program.

Comment 004-05: NEI recommends that the phrase without requesting relief under paragraph (f)(5) of this section or alternatives under paragraph (z) of this section be retained in 10 CFR 50.55a(f)(4) or this change be analyzed for justification under the backfit rule per 10 CFR 50.109(a)(1).

10 CFR 50.55a(f)(4) requires that pumps and valves classified as ASME BPV Code Class 1, 2, 3, and non-Code Class be included within the scope of the IST program. Non-Code Class components are allowed to deviate from ASME OM Code requirements without asking for prior NRC approval, provided that the basis for the deviation is justified to meet an acceptable level of quality and safety, or that implementing the Code requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety and the justification is documented in the Owners IST Program Plan. In the draft Rulemaking the phrase without requesting relief under paragraph (f)(5) of this section or alternatives under paragraph (z) of this section" has been deleted.

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The deletion of this phrase implies that there are some cases where non-Code Class components will require prior NRC approval without stating what those cases are. Owners currently maintain justifications for non-Code Class components that deviate from ASME OM Code requirements without prior NRC approval as allowed in 10 CFR 50.55a(f)(4). If the phrase is deleted these currently implemented justifications could be determined to require prior NRC approval even though the current CFR allows this. It appears that the deletion of this phrase imposes a new generic requirement causing licensees to modify procedures and therefore meeting the definition of a backfitting under 10 CFR 50.109(a)(1).

Comment 006-12: Exelon is requesting clarification concerning the removal of the statement:

"without requesting relief under paragraph (f)(5) of this section or alternatives under paragraph (z) of this section." Is the intent of this change to require prior NRC approval for non-Code Class components to deviate from ASME OM Code requirements? Exelon believes further clarification is needed.

Comment 008-06: The proposed change to 10 CFR 50.55a(f)(4) removes valuable wording and changes implementation requirements in a manner that could result in excessive and potentially unexpected relief requests from licensees, and could represent a significant administrative burden for many licensees and the NRC. The current wording allows licensees to document an alternative position for components not classified as ASME BPV Code Class 1, Class 2, or Class 3 without requiring regulator approval. The proposed removal of this wording would indicate that the NRC expects to approve relief for components within the augmented IST program. TVA recommends that the current statement, without requesting relief under paragraph (f)(5) of this section or alternatives under paragraph (z) of this section, remain within the CFR as currently approved. This statement was included to minimize the burden on licensees for non-Code components, and should be retained unless the need for additional review requirements is demonstrated.

As an example, there are numerous non-Code valves that perform a safety function that may not have been designed to be explicitly tested to ASME OM Code Requirements. At present, licensees may internally document deviations from the ASME OM Code relying on technical positions within the respective augmented IST programs. The proposed CFR change above would immediately result in each of these positions requiring relief from the NRC, and may place licensees in violation of 10 CFR 50.55a(f)(4).

TVA perceives that this change would be an expansion of regulatory oversight and burden, and as such, would be a backfit that requires analysis and justification to implement.

TVA recommends that the current statement, without requesting relief under paragraph (f)(5) of this section or alternatives under paragraph (z) of this section remain unchanged in the CFR. If this statement is to be removed as proposed, TVA recommends that it be evaluated and justified as a backfit under 10 CFR 50.109.

NRC Response to Comments 001-02, 002-05, 004-05, 006-12, and 008-06: The NRC agrees with these comments that the proposed removal of the phrase without requesting relief under paragraph (f)(5) of this section or alternatives under paragraph (z) of this section from 10 CFR 50.55a(f)(4) rule could cause confusion. The NRC only intended to clarify the transition from the 45

ASME BPV Code,Section XI, to the ASME OM Code for the IST requirements for dynamic restraints as licensees update their IST Programs to the more recent editions of the ASME OM Code. There is no intent to require submittal of alternatives or relief requests when using augmented testing provisions for non-Code Class components.

The NRC determined the phrase without requesting relief under paragraph (f)(5) of this section or alternatives under paragraph (z) of this section to be unnecessary because the revised

§ 50.55a(f)(4) was intended to directly authorize this use of augmented IST programs, without reference to § 50.55a(f)(6)(ii). It is well established that relief or alternative requests are only necessary when licensees desire to deviate from the requirements of 50.55a, and because this use of augmented IST programs for non-Code Class pumps and valves within the scope of the ASME OM Code will now be directly authorized by § 50.55a(f)(4), it is no longer necessary to provide an exception from the apparent requirement for a relief or alternative request, which was created by the previous rules reference to § 50.55a(f)(6).

To avoid confusion, the NRC has revised 10 CFR 50.55a(f)(4) to clarify that prior NRC approval is not necessary to apply the augmented testing provisions for non-Code Class pumps and valves within the scope of the ASME OM Code.

Comment 005-29: ASME believes that the § 50.55a(f) requirements for snubbers has been confusing to Owners, so the proposed change may help clarify these requirements. ASME questions whether the conditions specified in § 50.55a(b)(3)(v) are still needed as a result of the proposed changes to § 50.55a(f)(4) and § 50.55a(g)(4).

ASME also suggests that the reference to (b)(3)(v) in the last sentence of this condition be changed to (b)(3)(v)(A) for clarity.

NRC Response to Comment 005-29: The NRC appreciates the feedback but does not consider a modification to the proposed rule language to be appropriate at this time. The NRC has determined that to avoid confusion, the conditions specified in §50.55a(b)(3)(v) of the proposed rule are needed because (1) some licensees are still using the ASME BPV Code,Section XI, or are in the process of updating from ASME BPV Code,Section XI, to the ASME OM Code for snubber examination and testing, and (2) licensees have the option of implementing the snubber program as part of either the IST or inservice inspection (ISI) program. Therefore, the conditions specified in § 50.55a(b)(3)(v) are necessary at this time but could be removed in the future when all nuclear power plants are using the ASME OM Code for snubber examination and testing.

In addition, the NRC does not agree with the suggestion in the comment to change (b)(3)(v) to (b)(3)(v)(A) in the last sentence of § 50.55a(f), because some licensees must use 10 CFR 50.55a(b)(3)(v)(A) and others 10 CFR 50.55a(b)(3)(v)(B) depending on the specific plants code of record for the snubber program as part of either the IST or ISI program.

The NRC did not change the final rule as a result of this comment.

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Comment 006-11: With regard to the statement: "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," Exelon requests clarification whether the citation should be (f)(7)(ii) since it appears that the NRC is adding Section (7).

NRC Response to Comment 006-11: The NRC disagrees with the comment that the reference should be paragraph (f)(7)(ii). The appropriate reference, relating to augmented IST Programs, is 10 CFR 50.55a(f)(6)(ii).

The NRC did not change the final rule as a result of this comment.

d. 10 CFR 50.55a(f)(7), Inservice Testing Reporting Requirements Comment 001-03: The proposed 10 CFR 50.55a(f)(7) wording would expand the requirement of licensees to submit their IST Plans and interim IST Plan updates related to pumps and valves, and IST Plans and interim Plan updates related to snubber examination and testing to the NRC when the final safety analysis report for the applicable nuclear power plant is updated.

Submittal of interim IST Plan updates for pumps and valves and snubber examination and testing is not currently required. The new requirement to submit IST Plan updates to the NRC is considered unnecessary and overly burdensome. Currently, program plans associated with the ASME OM Code are submitted to the NRC for information prior to the beginning of each 10-year interval. These program plan submittals are deemed adequate for the NRC to perform their technical reviews of any associated alternative and relief requests.

The current revision of the ASME OM Code IST program Plans are available to onsite resident inspectors, who can provide the latest revision to interested NRC technical staff and regional inspectors upon request. Furthermore, NRC inspectors typically request licensees to either provide, or have available upon arrival, the latest Plan documents prior to scheduled inspections. An OM Code IST program Plan is considered a living document and could go through several revisions within a 10-year interval. The proposed requirement may result in licensees not updating their ASME OM Code program plans as often due to the extra burden of having to send revisions to the NRC.

In summary, since the NRC Resident Inspector currently has access to the most recent revision of a licensees ASME OM Code program Plan and is able to distribute them to others within the NRC organization upon request, it is recommended that the additional proposed requirement to submit interim IST Plan updates be deleted.

Comment 002-06: Recommend revising (f)(7) to only require submittal of IST plans when there is a demonstrated need (e.g., planned inspection) or at the beginning of each IST interval.

Bases / Background An ISTOG poll was conducted and of the 23 respondents: 13 stated they submitted their IST plans only at the beginning of the interval; 8 stated they submitted their IST plans after major 47

revisions; and 2 stated they submitted their IST plans both at the start of the interval and after major revisions. No one responded that they submitted more frequently.

Licensee processes for making formal docketed submittals to NRC are very time and labor intensive. The process requires each element of the submittal to be validated with supporting documentation. This effort would be a significant burden considering IST plans includes hundreds of components and technical requirements.

IST plans are frequently revised (sometimes multiple times per year) to address modifications or other changes in the program. Therefore, the proposed (f)(7) timing for submitting IST plans when the final safety analysis report for the applicable nuclear power plant is updated would not ensure the NRC has the latest version of a sites IST plan.

This proposed change represents a new requirement which would require changes to several licensee procedures for licensing activities and IST program activities. This new requirement would create a significant burden on licensees to submit their IST plans at least every two years without any compensating increase in quality or safety.

Comment 004-06: NEI recommends that § 50.55a(f)(7) not be included in the rule change to be consistent with Inservice Inspection plans or as a minimum only require submittal of IST Plans as part of interval updates.

If the NRC includes the proposed section 50.55a(f)(7) in the final rule, then the agency should provide a backfitting analysis supporting imposition of the amended regulation, as required by section 50.109(a)(3).

The proposed addition of § 50.55a(f)(7) will increase the frequency of the IST program plan submittals, thereby resulting in additional, unnecessary regulatory burden. The new wording ties the IST Program Plan submittals to the Updated Final Safety Analysis Report (UFSAR) submittals. Section 50.71 (e)(4), requires that licensees file updated UFSARs annually or 6 months after each refueling outage provided the interval between successive updates does not exceed 24 months. Tying submittal of IST Program Plans to UFSAR updates will require the filing of IST Plans multiple times each interval. In contrast, the current editions of the ASME OM Code allows for a single submittal for the new 10-year interval and possible updates during the 10 years. If included in the final rule, this change will result in increased costs due to additional internal processing and reviews and will require changes to plant procedures (in many cases both regulatory procedures and IST program procedures).

In the proposed rule, NRC explained the need for this change stating that the agency needs these IST Plans for use in evaluating relief and alternative requests and to review deferral of quarterly testing to cold shutdowns and refueling outages. (86 Fed. Reg. 16,087, 16,096) But, as implemented in current editions of the ASME OM Code, IST Program Plans are not submitted until implemented at the beginning of each interval, i.e., after the start of the interval.

Licensees typically submit relief requests prior to the start of the interval such that intervals are started with the appropriate code reliefs in place. Submitting an updated IST Program Plan after the start of the interval does not aid the NRC in the review of these relief requests.

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Additionally, even an updated IST Program Plan submitted on the schedule proposed in section 50.55a(f)(7) may contain outdated information if it is used by NRC to review relief requests that are submitted after the start of the 10-year interval, but prior to the next UFSAR revision. If the NRC requires information from a licensees current IST Program Plan in order to review a relief request, the staff may request that information as part of its review of that specific relief request. This is the most efficient way for the NRC staff to ensure that it has the most up-to-date information necessary to complete its review. Thus, there is no safety benefit associated with increasing the frequency of IST Plan submittals.

We also note that Code Case N-778, Alternative Requirements for Preparation and Submittal of Inservice Inspection Plans, Schedules, and Preservice and Inservice Inspection Summary Reports,Section XI, Division 1, as endorsed in the most recently approved Revision to Regulatory Guide 1.147, has eliminated the submittal of the Inservice Inspection Program Plans for the Inservice Inspection Program. If the proposed section 50.55a(f)(7) is included in the final rule, it will unnecessarily create inconsistencies between the IST and ISI programs, with no corresponding benefit to safety.

As discussed in the Federal Register Notice that endorsed the use of Code Case N-778 (83 FR 2331, dated January 17, 2018):

The NRC reviewed its needs with respect to the submittal of the subject plans, schedules, and reports, and determined that it is not necessary to require the submittal of plans and schedules.

The NRC made this determination because the latest up-to-date plans and schedules are available at the plant site and can be requested by the NRC at any time.

We see no reason why having current program plans available at plant sites and furnished by licensees upon request would be sufficient for the ISI program, but insufficient for the IST program.

Finally, from a backfitting perspective, section XII of the Federal Register notice states that the proposed rule would:

Add § 50.55a(f)(7) to state that IST Plans and interim IST Plan updates for pumps, valves, and dynamic restraints (snubbers) must be submitted to the NRC. This requirement was specified in the ASME OM Code up to the 2020 Edition, but the ASME removed this requirement from the 2020 Edition of the ASME OM Code as more appropriate to the regulatory authority responsibilities. Therefore, this rule change is not a backfit because the NRC is continuing the current requirement and is not imposing a new requirement.

But this description does not acknowledge that tying the submittal of IST Program Plans to submittal of the UFSAR will increase the frequency of the filings and is thus substantially different from current OM Code language. As proposed, section 50.55a(f)(7) would impose a requirement that is substantially different from the existing requirement (i.e., the pre-2020 Edition of the ASME OM Code), as well as the 2020 Edition of the ASME OM Code that is being incorporated-by-reference in this rulemaking (which eliminates the requirement to submit IST Plans altogether).

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As described in NUREG/BR-0058, Appendix D Guidance on Regulatory Analysis Related to ASME Code Changes, one of the scenarios in which the NRC considers adoption of a later code provision backfitting is when the NRC takes an exception to an ASME BPV or OM code provision and imposes a requirement that is substantially different from the current existing requirement as well as substantially different than the later code... This is precisely what will result if section 50.55a(f)(7) is included in the final rule - the pre-2020 OM Code requirement allows a single submittal of the IST Plans at start of the interval, the 2020 OM Code does not require submittal at all, and the proposed section 50.55a(f)(7) would require submittal at least once every 24 months with the FSAR updates. Further, as state above, if this change in finalized it will require licensees to modify procedures required to implement their ASME Code programs and FSAR updates. Thus, this proposed amendment to section 50.55a meets the definition of backfitting contained in 10 CFR 50.109 and must meet the requirements of section 50.109(a)(3) prior to being imposed on licensees.

Comment 006-13: Regarding the proposed requirement to provide IST plans on a periodic basis, Exelon believes that this will impose an undue burden with no added value and safety benefit and requests further clarification. Inservice Inspection (ISI) does not have the same requirement.

Comment 008-07: The proposed addition of 10 CFR 50.55a(f)(7) is a burdensome change with no commensurate benefit to public health and safety. TVA recommends removal of this proposed requirement. This new administrative requirement would require a broad revision of licensee administrative procedures and processes, without commensurate benefit. Even without this proposed regulation, the licensee must work to the latest approved program document, and it must be available to the regulator upon request. During any inspection or event that requires the NRC to review an IST Program for requirements, the latest copy is generally requested and duly provided by the licensee. Additional preparation, verification, and review time for the increased frequency required by the proposed change for submittal of IST Program documents, which are typically several hundred pages, could require significant additional resource burden without commensurate benefit to safety or quality. While TVA recommends removal of this proposed change, if NRC pursues implementation, this change should be evaluated and justified as a backfit under 10 CFR 50.109.

TVA recommends removing the addition of 10 CFR 50.55a(f)(7) from this proposed change. If addition of 50.55a(f)(7) is pursued, TVA recommends that it be evaluated and justified as a backfit under 10 CFR 50.109.

NRC Response to Comments 001-03, 002-06, 004-06, 006-13, and 008-07: The NRC agrees with the comments in part and disagrees with the comments in part. The NRC agrees that licensees of operating nuclear power plants do not need to submit interim IST Program Plans.

The NRC removed the provision for submittal of interim IST Program Plans from the final rule language; the requirements in 10 CFR 50.55a(f)(7) of this final rule reflect this change.

However, the NRC disagrees with the suggestion to eliminate § 50.55a(f)(7) altogether. The NRC needs the IST Program Plans for nuclear power plants for use in evaluating relief and alternative requests submitted by nuclear power plant licensees, and to review deferral of quarterly testing of components to cold shutdowns and refueling outages at nuclear power plants. The NRC also needs the IST Program Plans to support the review of unexpected issues related to pumps, valves, and dynamic restraints at nuclear power plants that need prompt 50

attention to evaluate their safety significance and the planned actions by the nuclear power plant licensee. The requirement to submit the IST Program Plan at the beginning of each 10-year IST Program interval is consistent with requirement that was specified in the ASME OM Code prior to the 2020 Edition. Therefore, the requirement to submit the initial IST Program Plan for each 10-year IST Program interval will remain in 10 CFR 50.55a(f)(7). Maintaining the requirement for the submittal of the initial IST Program Plan for each 10-year IST Program interval from earlier editions of the ASME OM Code in 10 CFR 50.55a(f)(7) is not a backfit. As needed, the NRC will request submittal of the updated IST Program Plans during review of relief or alternative requests.

IV. Other Comments

a. Comments in Support of Proposed Rule Language Comments 005-01, 005-04, 005-05, 005-06, 005-07, 005-09, 005-10, 005-11, 005-12, 005-14, 005-19, and 005-28: Several commenters expressed their support of proposed revisions to various provisions of the rule. Specifically, one commenter expressed their support of the NRCs proposed revision to 10 CFR 50.55a(b)(1)(iv); proposed deletion of 10 CFR 50.55a(b)(2)(viii)(A) through (D); proposed revision to 10 CFR 50.55a(b)(2)(ix)(B); proposed deletion of 10 CFR 50.55a(b)(2)(ix)(C) through (E); proposed changes in 10 CFR 50.55a(b)(2)(xviii)(D) to provide alternative personnel qualification provisions; proposed change to 10 CFR 50.55a(b)(2)(xxv)(B)(2) to clarify that corrosion rates may be determined at alternative locations; and proposed relaxation of condition 10 CFR 50.55a(b)(3)(xi) for valves that are not susceptible to stem-disk separation.

NRC Response to Comments 005-01, 005-04, 005-05, 005-06, 005-07, 005-09, 005-10, 005-11, 005-12, 005-14, 005-19, and 005-28: The NRC appreciates the feedback on the proposed revisions to various provisions of the rule.

Comment 005-03: This condition removes references to several older editions and addenda of Section XI that are no longer in use in the United States. ASME supports the proposed revision to § 50.55a(b)(2)(viii).

NRC Response to Comment 005-03: The NRC appreciates the feedback on the proposed revision to 10 CFR 50.55a(b)(2)(viii).

Comment 005-08: This condition removes references to several older editions and addenda of Section XI that are no longer in use in the United States. ASME supports the proposed revision to § 50.55a(b)(2)(ix).

NRC Response to Comment 005-08: The NRC appreciates the feedback on the proposed revision to 10 CFR 50.55a(b)(2)(ix).

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Comment 005-24: ASME supports the endorsement of Nonmandatory Appendix R, Supplement 2 in the 2017 Edition and appreciates the NRC proposing this change to allow use of Appendix R, Supplement 2 without requiring prior NRC authorization in accordance with

§ 50.55a(z).

NRC Response to Comment 005-24: The NRC appreciates the feedback on the proposed revision to 10 CFR 50.55a(b)(2)(xxix).

Comment 005-30: ASME believes that the § 50.55a(g) requirements for snubbers has been confusing to Owners, so the proposed change may help clarify these requirements.

NRC Response to Comment 005-30: The NRC appreciates the feedback on the proposed revision to 10 CFR 50.55a(g)(4).

b. Typographical Errors Comment 005-18: ASME notes that there are two typographical errors in the proposed revision to this condition. In § 50.55a(b)(2)(xxv),Section XV Condition should be changed to Section XI Condition, and in § 50.55a(b)(2)(xxv)(A), First person should be changed to First provision.

NRC Response to Comment 005-18: The NRC agrees that the proposed rule contained two typographical errors as identified in the comment. The staff corrected the typographical error in condition (b)(2)(xxv)(A) in the Federal Register notice published on May 12, 2021 (86 FR 25977). The final rule includes both corrections.

Comment 008-01: On page 16111 of Reference 1, 10 CFR 50.55a(b)(2)(xxv) heading,Section XV Condition is incorrect, and, as noted in 86 FR, in the proposed section (xxv)(A),

First person should be changed to First provision.

NRC Response to Comment 008-01: The NRC agrees that the proposed rule contained two typographical errors as identified in the comment. The staff corrected the typographical error in condition 10 CFR 50.55a(b)(2)(xxv)(A) in the Federal Register notice published on May 12, 2021 (86 FR 25977). The final rule includes both corrections.

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