ML25065A034
| ML25065A034 | |
| Person / Time | |
|---|---|
| Site: | Nuclear Energy Institute |
| Issue date: | 01/22/2025 |
| From: | Basso T Nuclear Energy Institute |
| To: | Christian Araguas Office of Nuclear Regulatory Research, NRC/SECY/RAS |
| References | |
| Download: ML25065A034 (1) | |
Text
Tom Basso Senior Director, Engineering and Risk Phone: 202.739.8049 Email: tbb@nei.org January 22, 2025 Mr. Christian Araguas Director, Division of Engineering Office of Nuclear Regulatory Research Mail Stop O5-G10 Nuclear Regulatory Commission Washington, DC 20555-0001 and Office of the Secretary U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 ATTN: Rulemakings and Adjudications Staff
Subject:
NEI Request and Input for Current 10 CFR 50.55a Rule Making Project Number: 689
Dear Rulemaking and Adjudications Staff,
The Nuclear Energy Institute (NEI)1, on behalf of our members, is submitting proposed changes to 10 CFR 50.55a for the NRC to consider as part of the current rule making and inclusion of code cases in the next draft revisions to Regulatory Guides 1.84, and 1.147, as recommended herein.
These rule changes and endorsement of code cases would result in increased efficiencies in the application of ASME Section III and Section XI. They would also simplify regulatory processes, benefiting both the NRC and the industry. NEI with its members urge the NRC to incorporate these recommendations into the current rulemaking.
To support your consideration of our request, a brief explanation of the proposed changes to 10 CFR 50.55a and justification is provided in Attachment 1 with this letter. Similarly, Attachment 2 provides the basis for consideration of including the Section III code cases in next revision of RG 1.84.
1 The Nuclear Energy Institute (NEI) is responsible for establishing unified policy on behalf of its members relating to matters affecting the nuclear energy industry, including the regulatory aspects of generic operational and technical issues. NEIs members include entities licensed to operate commercial nuclear power plants in the United States, nuclear plant designers, major architect and engineering firms, fuel cycle facilities, nuclear materials licensees, and other organizations involved in the nuclear energy industry.
Rulemaking and Adjudications Staff January 22, 2025 Page 2 Nuclear Energy Institute A similar letter was submitted by ASME Board on Nuclear Codes and Standards on behalf of the ASME Boiler and Pressure Vessel Committee on Nuclear Inservice Inspection (BPV XI) for the NRC to consider including Section XI, Division 1 Code Cases N-752-2, N-788-2, N-926, N-935, and N-939 in draft revision 22 to Regulatory Guide 1.1472. NEI supports the ASME Board of Nuclear Codes and Standards request, and believes the bases provided to justify endorsement of each of these code cases is appropriate.
Please contact me at tbb@nei.org or (484) 366-7534 with any questions or comments about the content of this letter or the attachments.
Sincerely, Thomas Basso Senior Director, Engineering and Risk
- Proposed Changes to 10 CFR 50.55a : ASME III Code Cases for Endorsement c:
Andrea Veil, NRR/NRC Gregory Bowman, NRR/NRC Eric Benner, NRR/NRC Mike Franovich, NRR/NRC Michele Sampson, NRR/NRC 2 ML24296A006
- Proposed Changes to 10 CFR 50.55a NEI is recommending the NRC make the following changes as part of the current 10 CFR 50.55a rule making. The recommended changes include the removal of specific conditions which NEI believes are not necessary to ensure safety (as demonstrated by long-standing safety performance) or are no longer needed by the industry. NEI proposes the NRC consider the following specific changes based on the justifications provided below:
- 1. Deletion of 10 CFR 50.55a(h),
- 2. Deletion of Section XI Condition 10 CFR 50.55a(b)(2)(xxvi),
- 3. Inclusion or clarification of 10 CFR 50.55a(y) to 10 CFR 50.55a(z).
Deletion of 10 CFR 50.55a(h)
In a previous letter3 addressing implementation of section 507 of the Advance Act, NEI proposed that the NRC eliminate 10 CFR 50.55a(h), which incorporates by reference IEEE Standard Criteria for Safety Systems (IEEE 279-1969, IEEE 279-1971, or IEEE 603-1991). Section 507 of the ADVANCE Act requires the NRC to identify improvements to the reactor and materials oversight and inspection programs using risk-informed, performance-based procedures, expanded incorporation of information technologies, and staff training. As described in the referenced letter, NEI believes that the General Design Criteria provides sufficient requirements for safety systems. In addition, the IEEE standards endorsed in 50.55a(h) are dated and overly prescriptive for current technologies. For example, the new NRC guidance for non-LWRs (Digital Instrument and Controls Design Review Guide) has many allowances for exemptions to some of the design principles that are the basis for the endorsed IEEE standards, e.g., Single Failure Criterion.
NRC and industry interactions on NEIs proposal to remove 50.55a(h) are being scheduled as part of the activities related to implementation of the Advance Act. NEI is repeating this recommendation in this letter since it would require an amendment to 10 CFR 50.55a.
Deletion of Section XI Condition 10 CFR 50.55a(b)(2)(xxvi)
(xxvi)Section XI condition: Pressure Testing of Class 1, 2, and 3 Mechanical Joints. Mechanical joints in Class 1, 2, and 3 piping and components greater than NPS-1 that are disassembled and reassembled during the performance of a Section XI repair/replacement activity requiring documentation on a Form NIS-2 must be verified to be leak tight. The verification must be performed to the standards of the licensees appendix B to this part quality assurance program.
NEI recommends removing this condition related to leakage checks on mechanical connections. This condition results in no additional repair or replacement action by licensees. The condition requires another layer of documentation and oversight beyond station quality assurance program practices and procedures for a standard practice. Regardless of this condition, the appropriate Post Maintenance Testing is performed and documented as a standard maintenance practice to confirm mechanical connections are 3 ML24302A311 Page 2 leak tight or within the limits required to maintain operability as required by plant quality assurance program and procedures. Deletion of this condition would provide an efficiency gain by removing these redundant and unnecessary regulatory requirements.
Inclusion or clarification of 10 CFR 50.55a(y) to 10 CFR 50.55a(z) 10 CFR 50.55a(y) Definitions was incorporated into the rule during the most recent change to 10 CFR 50.55a [89 FR 58039]. 10 CFR 50.55a(z) Alternatives to codes and standards requirements provides a licensee to seek Alternatives to the requirements of paragraphs (b) through (h) of this section or portions thereof may be used when authorized by the Director, Office of Nuclear Reactor Regulation.
Paragraph (y) is not covered by the provision to seek an alternative under paragraph (z). Therefore, a licensee would have to seek an exemption under 10 CFR 50.12 for an alternate to (y) or any code case or code requirement that involves or potentially impacts any definitions in (y). This was recently raised during a public meeting with the NRC on seeking approval to apply ASME XI code case N-921 since it impacted what is defined as an interval. This result is at odds with the rationale provided in the 2014 final rule amending section 50.55a to include paragraph (z).4 In that rulemaking, the NRC added paragraph (z) to section 50.55a specifically to allow applicants and licensees to request authorization of alternatives for changes to conditions on NRC-approved ASME Code Cases and to allow applicants and licensees to request authorization to alternatives for changes to conditions on Section II and XI of the ASME BPV Code and OM Code.5 Requiring applicants and licensees to request exemptions for approval of alternatives to conditions on approved Code Cases or code provisions, which also happen to implicate definitions in paragraph (y), needlessly adds administrative burden to the review and approval processes for both NRC staff and industry. Thus, NEI recommends that the NRC expand the applicability of 10 CFR 50.55a(z) to include paragraph (y) or otherwise revise paragraph (y) to avoid the need for exemptions to cover approval of alternatives that could otherwise be approved via the relief request process.
4 NRC, Approval of American Society of Mechanical Engineers Code Cases, Final Rule, 79 Fed. Reg. 65776 (Nov. 5, 2014).
5 Id. at 65792.
- ASME III Code Cases for Endorsement NEI requests inclusion of the following ASME Section III, Division 1 Code Cases in draft revision 41 to Regulatory Guide 1.84:
- 1. N-883 - Construction Prior to the Establishment of an Owner
- 2. N-915 - Extension of Internal Audit and Supplier Audit Due Dates in Exigent Conditions
- 3. N-916 - Remote Verification and Witness of Activities
- 4. N-818 Use of NDE and Fracture Mechanics for Acceptance of Full Penetration Butt Welds In lieu of Weld Repair, Class 1 and 2,Section III Division 1
- 5. N-907 - Rules for Performing Preservice Inspection (PSI) During Construction,Section III, Division 1
- 6. N-659 Use of Ultrasonic Examination in Lieu of Radiology for Weld Examination,Section III, Division 1 and 2 The basis for the NRC to consider inclusion of these code cases is presented in the table below.
Code Case Rev Title NRC Status Basis for NRC Action Basis For Recommendation to Reconsider N-883 0
Construction Prior to the Establishment of an Owner Conditioned Need to be an owner to use the Case.
Revised Case is pending.
ASME and the NRC have conducted numerous meetings, including public meetings on this issue. ASME has modified the Code Case to address NRC concerns. The advanced reactor fleet intends to deploy using a very different economic model, including factory-built reactors. Further, given very long lead times for component construction and the need for shorter plant construction durations, it is vital that fabrication begin well in advance of the establishment of the owner.
The Code has always permitted smaller items (NPS
- 4) to be constructed using this approach; therefore, this is not new in the Code, it has simply been expanded to permit a wider range of construction.
Page 2 Code Case Rev Title NRC Status Basis for NRC Action Basis For Recommendation to Reconsider N-915 0
Extension of Internal Audit and Supplier Audit Due Dates in Exigent Conditions Not Approved Numerous Technical Issues During the Pandemic, the industry successfully implemented audit extensions, without resulting in any documented safety consequence. The flexibility this Case provides is important given the scope and reach of the supply chain. The Code Case follows NQA-1 and published NRC guidance. It should also be taken into consideration that current digital technology provides a better capability for maintaining the integrity of remote verification than what was available when the requirements for verification were established.
N-916 0
Remote Verification and Witness of Activities Not Approved Not clearly linked to emergencies, and could be widely used During the Pandemic, the industry successfully conducted remote verification and witnessing, without resulting in any documented safety consequences, essentially proving that the technology and tools are available to support remote witnessing. The Code Case is specific to activities requiring verification or witness by Section III. It does not cover the acceptance of items or services through source verification. Certificate Holders must still meet any applicable regulatory requirements.
Page 3 Code Case Rev Title NRC Status Basis for NRC Action Basis For Recommendation to Reconsider N-818 1
Use of NDE and Fracture Mechanics for Acceptance of Full Penetration Butt Welds In lieu of Weld Repair Not Approved Numerous Technical Issues LWR experience has shown that numerous in-service defects and failures initiate at the location of fabrication weld repairs. The Case provides a technically sound basis, based on LWR experience, to accept indications in lieu of weld repairs, reducing, no increasing, the likelihood of inservice failures.
N-907 0
Rules for Performing Preservice Inspection (PSI)
During Construction, Not Approved Long Standing issues with when PSI is performed. Revisions are in progress ASME and the NRC have conducted numerous meetings, including public meetings on this issue. ASME is modifying the Code Case to address NRC concerns. There is no safety concern with the timing of PSI and there are significant efficiencies in schedule and potential savings in cost.
N-659 3
Use of Ultrasonic Examination in Lieu of Radiography for Weld Examination Not Approved Until studies are complete that demonstrate the ability of UT to replace RT for construction, the NRC will not endorse UT in lieu of RT Code Cases or generically allow the substitution of UT in lieu of RT for construction examinations.
Ultrasonic Examination (UT) for construction has a long history in commercial codes, demonstrating that this is a safe and practical alternative.
Section III already permits, and has long permitted, UT for some geometries, so this is not new. Use of UT in the field during construction presents significant efficiencies in schedule and potential savings in cost.