ML24191A343
ML24191A343 | |
Person / Time | |
---|---|
Issue date: | 08/06/2024 |
From: | James Downs NRC/NMSS/DFM/FFLB |
To: | Lav S NRC/NMSS/DFM/FFLB |
References | |
Download: ML24191A343 (1) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 MEMORANDUM TO: Samantha C. Lav, Chief Fuel Facility Licensing Branch Division of Fuel Management Office of Nuclear Material Safety and Safeguards FROM: James R. Downs, Senior Project Manager Fuel Facility Licensing Branch Division of Fuel Management Office of Nuclear Material Safety and Safeguards
SUBJECT:
SUMMARY
OF JUNE 27, 2024, PUBLIC MEETING - FUEL FACILITY STRUCTURES AS ITEMS RELIED ON FOR SAFETY On June 27, 2024, the U.S. Nuclear Regulatory Commission (NRC) staff held a partially closed meeting with representatives from the Nuclear Energy Institute (NEI) and the fuel cycle industry to discuss the designation of fuel facility structures as items relied on for safety (IROFS), as requested in their letter dated May 23, 2024 (Agencywide Documents Access and Management System Accession No. [ADAMS] ML24159A731). The meeting notice is available in the NRCs ADAMS (ML24166A217). This hybrid meeting was held in-person, at the NRC Headquarters, and via teleconference using the Microsoft Teams platform. The enclosed attendance list provides the attendees for the meeting, as captured by the NRC staff. The staff plans to formally respond, in writing, to NEIs letter at a later date.
During the meeting, the NEI representatives discussed their letter using a slide presentation (ML24172A195). Then the NRC staff discussed which regulatory requirements in Title 10 of the Code of Federal Regulations (10 CFR) are applicable to IROFS, what those requirements say, and how the industry has met those requirements. The staff clarified that its position on structures as IROFS is not new and does not assume that all new structures that house activities under the scope of 10 CFR Part 70, Subpart H need to be IROFS. The staff discussed an apparent misunderstanding of what can be assumed as starting conditions for an integrated safety analysis (ISA). The meeting concluded with attendees agreeing upon on a list of several related topics that could warrant future discussion.
CONTACT: James R. Downs, NMSS/DFM 301-415-7744August 6, 2024 Signed by Downs, James on 08/06/24
S. Lav 2
The following key messages were discussed (ML24166A224) during the NRC staffs presentation:
- 1) The regulations in 10 CFR Part 70, Subpart H, require an applicant or licensee to establish and maintain a safety program that, in part, demonstrates compliance with the performance requirements of 10 CFR 70.61 by performing an ISA to demonstrate that the risk of each credible, intermediate-and, high-consequence event is limited, in accordance with the performance criteria in 10 CFR 70.61(b) & (c) - related to inadvertent criticality, chemical exposure, uranium uptake, and radiological dose that can lead to long-term health effects to workers or the public.
- 2) The NRC staffs stated position is that engineered or administrative controls (e.g., structures, systems, equipment, components, and activities of personnel) used to prevent or mitigate events and their consequences (i.e., used to meet the performance requirements of 10 CFR 70.61) may not be considered in the determination of consequences (i.e., you can cannot rely on them to prevent or mitigate a consequence) unless those controls are designated as IROFS, in accordance with 10 CFR 70.61(e).
- 3) The regulations do not specifically require structures (or any specific system, equipment, component, or activity) to be designated as IROFS. However, to develop the safety basis for a facility, the requirements of 10 CFR 70.62(c)(iv) & (vi) state that an applicant or licensee must identify potential accident sequences caused by process deviations or other events internal to the facility and credible external events, including natural phenomena hazards (NPH), and identify each IROFS; the characteristics of its preventive, mitigative, or other safety function; and the assumptions and conditions under which the item is relied upon to support compliance with the performance requirements of 10 CFR 70.61.
- 4) Since the 2000 issuance of 10 CFR Part 70, Subpart H, the NRC staff has maintained its position on the applicability of those requirements to new structures/processes for special nuclear material (SNM)1. In license applications and amendment requests having new structures/processes for SNM, fuel cycle facilities have typically credited the design of critical structures and internal components for the processing of quantities of SNM with the potential to exceed the consequence thresholds of 10 CFR 70.61 and its capacity to prevent or mitigate the consequences from credible external events (e.g., high winds, tornados, intense precipitation, snow loading, seismic events) to demonstrate compliance with the performance requirements of 10 CFR 70.61 for NPH.
- 5) The NRC staff has identified inconsistencies between the regulations and the NRC-accepted IROFS designations made by licensees for NPH events for some existing structures/processes at facilities that were licensed prior to 2000 (i.e., before 10 CFR Part 70, Subpart H was issued). Because the staff remains confident that those existing structures are safe and can withstand NPH based on actions taken to address Generic Letter 2015-01, Treatment of Natural Phenomena Hazards in Fuel Cycle Facilities (ML14328A029), the staff has not explored potentially backfitting the requirements of 10 CFR Part 70, Subpart H, to ensure the IROFS designation for NPH events at those existing structures/processes are in strict compliance with the regulations.
1 as defined in 10 CFR 70.4, Definitions S. Lav 3
During the meeting, the NRC staff stated that they plan to formally respond to NEIs letter dated May 23, 2024. Additionally, the staff discussed several points of disagreement with the NEI letter.
The NRC staff stated its position (see key message #2 above) is a compilation of regulatory requirements and is not a new staff position. This staff position has existed since Subpart H was added to 10 CFR Part 70, almost 25 years ago.
The NRC staff confirmed that the facility-specific ISA determines the declaration of IROFS.
NPH, such as earthquakes, are types of common-cause events that have the potential to cause severe degradation and failure of structures and internal components. Depending on the facility location, NPH may be one of the leading contributors of facility risk and could result in significant risk to the public, worker, and environment. The facility-specific ISA determines the level of protection needed for NPH, but that facility-specific ISA must follow the requirements of 10CFR Part 70, Subpart H to demonstrate compliance with the performance requirements of 10 CFR 70.61.
The NRC staff stated that compliance with building codes does not support a determination that structures or components do not need to be designated as IROFS for NPH. Specific characteristics or qualifications of a control designated as an IROFS may include adherence or compliance with specific provisions of a building code and the provisions of that code (e.g.
structural demand and structural capacity) can be used to demonstrate the capability of structures and components to withstand the effects of NPH and meet their intended safety function. However, the regulations require that engineered or administrative controls (e.g.,
structures, systems, equipment, components, and activities of personnel) used to prevent or mitigate events and their consequences (i.e., used to meet the performance requirements of 10 CFR 70.61) may not be considered in the determination of consequences unless those controls are designated as IROFS, in accordance with 10 CFR 70.61(e).
The NRC staff confirmed that, consistent with the provisions of 10 CFR 70.62(e), when applicants or licensees designate structures as IROFS, they do so because they are relied upon to either prevent or mitigate the consequences of a criticality, acute chemical exposure, or uranium uptake, consistent with paragraphs (b) - (d) of 10 CFR 70.61, for specific external events. It is important to note that applicants or licensees do not need to designate a structure as an IROFS for a scenario where the unmitigated analysis of the consequences do not exceed the performance requirements, assuming the performance of the structure wasnt credited in making that determination. Based on its ISA, the applicant or licensee may determine it is not necessary to designate a structure as an IROFS - but then that facilitys ISA cannot rely on the performance of that structure in its determination of consequence.
The NRC staff discussed how the acceptable management measures that applicants or licensees have assigned to structures designated as IROFS typically address configuration control and maintenance, for which applicants or licensees may elect to use programs that are already in place and potentially minimize the overall burden. However, unlike the configuration management requirements discussed in 10 CFR 70.72, designating a control as an IROFS and applying the required management measures specifically ensures the availability and reliability of that controls safety function.
S. Lav 4
The NRC staff clarified that for new facilities, or new processes at existing facilities, applicants or licensees must also provide protection against NPH to demonstrate compliance with the baseline design criteria in 10 CFR 70.64(a)(2). As stated in the Federal Register (FR) notices (64 FR 41338; July 30, 1999, and 65 FR 56211; September 18, 2000) that were originally published for 10 CFR Part 70, Subpart H, The baseline design criteria do not provide relief from compliance with the safety performance requirements of 10 CFR 70.61. The baseline design criteria are generally an acceptable set of initial design safety considerations, which may not be sufficient to ensure adequate safety for all new processes and facilities. The ISA process is intended to identify all accident scenarios leading to facility risk and to identify additional safety features that maintain and improve the margin of safety needed to ensure adequate protection of health and safety. In other words, 10 CFR 70.64 ensures that a structure is properly constructed, while 10 CFR 70.61 is used to determine whether there is a reliance on the construction of that structure to prevent or mitigate a consequence that could exceed the performance requirements - in which case, the structure would be required to be designated as an IROFS.
The NRC staff discussed the activities associate with Generic Letter 2015-01 and how the staff verified each fuel facility could withstand NPH in light of the lessons learned from the events that resulted from the earthquake and tsunami in 2011 that impacted the nuclear power reactors in Fukushima, Japan. The staff clarified that it did not conduct a complete review to verify all design basis information, including the ISA. Therefore, an inspection report related to Generic Letter 2015-01 having no findings should not be interpreted as NRC approval of a facilitys ISA or its methodologies, or a guarantee that future facility changes wont have potential consequences that require additional IROFS for NPH. Based on the technical review of the licensee responses to Generic Letter 2015-01 and the results of the associated inspections, the staff concluded that fuel cycle licensees performed appropriate evaluations of NPH for their facilities. As a result, Generic Letter 2015-01 was closed in 2018 (ML18036A091).
Although the NRC staff stated that it believes the facility change process discussed in 10 CFR 70.72 remains adequate, the staff urged caution for licensees that utilize the process in 10 CFR 70.72(c), through which a change can be made without prior Commission approval. There are several provisions in that section of the regulations that a licensee must consider and appropriately document for NRC inspection. Similar to most fuel facility licensing issues, inspection oversight of a facility change is based on commitments made in the facilitys license application and compliance with the regulatory requirements - which, in the case of 10 CFR 70.72, includes a properly documented change evaluation.
After the NRC staff discussed its key messages, all persons in attendance (including any members of the public) were invited to ask questions or provide comments. Finding that there were no questions or comments, the staff concluded the open portion of the meeting. During the closed portion that followed, the staff discussed sensitive, security-related approaches that specific applicants or licensees have taken, or are considering taking, at their facilities.
Much of the discussion in the closed portion of the meeting focused on what could be assumed as the starting conditions/assumptions for performing different steps of the ISA, such as determining the credibility of an NPH initiating event, performing the unmitigated consequence analysis, and how those analyses differ from those typically performed for process upsets.
Those discussions highlighted key areas of misunderstanding that may require additional outreach to resolve. The staff and industry also discussed facility-specific methodologies for performing the ISA and how those impacts whether a structure or structural element would need to be designated as an IROFS. Finally, the staff and industry discussed potential impacts of S. Lav 5
designating a structure or structural component as an IROFS, including concerns over the potential designation of a sole IROFS, what could determine if a structural IROFS is degraded, and potential financial impacts associated with the regulatory requirements.
There were four topics that meeting attendees agreed could warrant future discussion - either facility by facility, or at a future stakeholders meeting:
- What clarification can be provided on the facility-specific scope and results of the NRCs activities from Generic Letter 2015-01?
- What is the burden (e.g., cost, level of inspection, required management measures, reporting) associated with designating a structure as an IROFS? Are there effective ways for the NRC to reduce that regulatory burden and maintain the level of safety?
- Is it appropriate to identify a structure designated as an IROFS as a sole IROFS per 10 CFR 70.65(b)(8)? What defines degraded for a structure designated as an IROFS?
- How and when can satisfying the baseline design criteria in 10 CFR 70.64 (e.g., building code compliance) be used as a basis for compliance with ISA requirements in lieu of more complex analysis for NPH (e.g., seismic fragility analyses)?
Enclosure:
Attendance List
ML24191A343 OFFICE NMSS/DFM NMSS/DFM NMSS/DFM NMSS/DFM NMSS/DFM NMSS/DFM NAME JDowns JGoodridge JLopez JMarcano SLav JDowns DATE 07/22/2024 07/22/2024 07/23/2024 07/24/2024 07/28/2024 08/06/2024 ATTENDANCE LIST
NAME AFFILIATION NAME AFFILIATION Robert Link Nuclear Energy InstituteMarilyn Maldonado COMM/OCMAC Janet Schlueter Nuclear Energy InstituteCelimar Valentin COMM/OCMAC Daniel Ashworth industry representative Robert Lewis NMSS Gerard Couture industry representative Kimyata Morgan-NMSS/DFM Butler Burns Cunningham industry representative Greta Knowles NMSS/DFM Jesus Diaz-Quiroz industry representative James Hammelman NMSS/DFM/CTCFB Richard industry representative Samantha Lav NMSS/DFM/FFLB Freudenberger Scott Gizzie industry representative Matt Bartlett NMSS/DFM/FFLB Holly Harvey industry representative James Downs NMSS/DFM/FFLB Tim Knowles industry representative Rin Iimi NMSS/DFM/FFLB Stephen Long industry representative Stephen Poy NMSS/DFM/FFLB Bob Maurer industry representative Jonathan Rowley NMSS/DFM/FFLB Ashley Morris industry representative Joe Rudd NMSS/DFM/FFLB Scott Murray industry representative Diana Woodyatt NMSS/DFM/FFLB Wyatt Padgett industry representative Christian Murphy NMSS/DFM/IOB Sean Patterson industry representative Juan Lopez NMSS/DFM/MSB Heather Petterson industry representative Bharatkumar Patel NMSS/DFM/MSB Tim Tate industry representative Tekia Govan NMSS/DFM/NARAB Carmen Teolis industry representative Mike Call NMSS/DFM/NARAB Jim Tomkins industry representative Timothy Grimes NMSS/DFM/NARAB Jennifer Wheeler industry representative Jonathan Marcano NMSS/DFM/NARAB Camille Zozula industry representative Araceli Billoch ColonOEDO/EO/OPS other individuals industry representative Dave McIntyre OPA Andrea Jennetta member of public Anthony Ponko R-II/DCO/CIB1 other individuals members of public Anthony Masters R-II/DFFI Cameron Ubben R-II/DFFI/PB1 Cynthia Taylor R-II/DFFI/PB2 other staff US NRC
Enclosure