ML21025A356

NEI, Implementation of the Recommendations of Industry'S November 8, 2019 White Paper, Defining Spent Fuel Performance Margins

ML21025A356
Person / Time
Site:	Nuclear Energy Institute
Issue date:	01/14/2021
From:	Mccullum R Nuclear Energy Institute
To:	Andrea Kock Division of Fuel Management
Araguas C
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ML21025A355	List: ML21025A356 ML21025A357
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Download: ML21025A356 (6)

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ROD MCCULLUM Sr. Director, Decommissioning & Used Fuel 1201 F Street, NW, Suite 1100 Washington, DC 20004 P: 202.739.8082 rxm@nei.org nei.org January 14, 2021 Ms. Andrea Kock, Director Division of Fuel Management Office of Nuclear Material Safety and Safeguards U.S. Nuclear Regulatory Commission Washington, DC 20555-0001

Subject:

Implementation of the Recommendations of Industrys November 8, 2019 White Paper, Defining Spent Fuel Performance Margins Project Number: 689

Dear Ms. Kock:

The Nuclear Energy Institute (NEI) 1, on behalf of its members, would like to thank NRC for the substantial level of effort and engagement that staff has conducted in response to the White Paper, Defining Spent Fuel Performance Margins, that we submitted just over a year ago. The purpose of this White Paper - to develop improvements in regulatory efficiency based on what has been learned about dry storage safety margin through the deployment of more than 3,000 storage systems over the past 33 years - has been largely satisfied. The purpose of this letter is to seek NRCs perspectives on what we have accomplished and request NRCs engagement in assessing our effectiveness going forward with the implementation of these improvements.

Full implementation of the actions taken as a result of the NRC-Industry dialogue on the White Paper, along with the completion of identified follow on activities, will have a transformative effect on the continued dry storage of spent fuel in the following ways.

• Safety will be enhanced by the refocusing of NRC and industry resources to the most safety significant areas.

• Efficiencies gained will enable suppliers to bring innovative new designs to market more quickly to address the increasing diversity of spent fuel discharges (including accident tolerant fuels).

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.

Ms. Andrea Kock January 14, 2021 Page 2

• Reactor operators will have greater flexibility in dry storage loading choices and there will be less risk of regulatory issues delaying dry storage loading campaigns.

• Decommissioning plants will be able to off-load their spent fuel pools earlier, which will support the growing trend toward accelerating the completion of decommissioning, which has become a key stakeholder interest.

Specifically, the White Paper made 16 recommendations based on an examination of margin in 5 areas, based on what is now understood about performance margin in each of these areas:

I) Source Terms II) Thermal Parameters III) Radiological Parameters IV) Fuel Qualification V) Criticality These recommendations fall into the following three categories:

1. Actions that industry can take within the confines of existing regulations and guidance

2. Actions that NRC can take by tailoring their regulatory guidance and their review and inspection practices to recognize the existence of performance margin

3. Actions that will need industry and NRC to engage in a dialogue to develop improved regulatory tools and guidance Throughout 2020, NRC and industry interacted extensively on 14 of these 16 recommendations. In some cases, actions were taken directly as recommended. In other cases, actions taken in response to one recommendation achieved the purposes of another. In still other cases activities already underway prior to the submittal of the paper were completed in ways that achieved the purposes of a given recommendation. In total, this dialogue resulted in the development of methods, tools, or approaches that - if implemented as intended - will reshape both industry and NRC licensing practices and result in significant efficiency improvements.

Industry had previously sought to improve the efficiency of dry storage licensing by petitioning for a rulemaking (PRM 72-7, dated October 3, 2012). In February 2020, industry determined that NRCs endorsement of the Graded Approach criteria (per Recommendation VI-1 of the White Paper) and progress being made on the other recommendations of our White Paper were sufficient to satisfy the central purpose of PRM 72-7. With that central purpose addressed, industry requested withdrawal of PRM 72-7. NRC formally announced the withdrawal of PRM in October 2020, hence obviating the need to devote resources to a time-consuming rulemaking.

Tables 1 through 3 below summarize what was accomplished, by category, on each recommendation as well as identifying the path forward to assure that the value of these achievements is fully realized going forward.

Ms. Andrea Kock January 14, 2021 Page 3 The roman numerals in the recommendation number link each recommendation to the functional area being addressed (listed above, as identified in the White Paper).

Table 1 - Actions that can be taken by industry within existing regulations Rec. # Summary Results Path Forward III-1 Utilize more realistic COMPLETE Industry to build more realistic source terms

• NRC endorsement of NEI 12-04 source terms into analyses as (9/22/20) provides industry with appropriate.

improved flexibility

• Action completed per Table 2 will provide additional flexibility III-2 Do not apply COMPLETE Industry to reduce reliance on uncertainty penalty on

• NRC endorsement of NEI 12-04 uncertainty penalties as top of conservative (9/22/20) provides improved appropriate.

source term flexibility

• Actions completed per Table 2 will provide additional flexibility IV-3 Develop and document COMPLETE Industry to apply, in future industry consensus

• Thermal Modeling, Decay Heat license and Certificate of thermal modeling Monitoring, and Fuel Performance Compliance (CoC) applications, practices PIRTS have been completed the insights documented in the

• Industry proposed new safety PIRTS and letters.

objective (5/13/20), NRC letter (6/1/20) agreed with approach, gross rupture PIRT process underway to define new safety objective that includes realistic and actionable fuel integrity metrics VI-1 Adopt and extend COMPLETE Industry to use the graded graded approach CoC

• NRC approved Orano pilot graded approach in future license and precedent (Per RIRP I- approach CoC (9/14/20) CoC applications.

16-01)

• NRC and industry aligned on future use of the graded approach (12/17/20 workshop)

Table 2 - Actions that can be taken by NRC within existing regulations Rec. # Summary Result Path Forward II-1 Graded Approach COMPLETE SUBJECT TO After clarifying how regulatory Review Process for CoC CLARIFICATION: transparency will be achieved in applications and

• NRC letter (1/24/20) defined staffs use of this tool, NRC to amendments licensing process expectations for implement this tool in its

Ms. Andrea Kock January 14, 2021 Page 4 more risk informed reviews licensing reviews.

• NRC developed a risk tool to enable a graded review process (12/17/20 workshop)

III-3 Less detailed reviews COMPLETE SUBJECT TO After clarifying how regulatory when conservatism is CLARIFICATION transparency will be achieved in demonstrated

• The NRC licensing process staffs use of this tool, NRC to implementations and risk tool (per implement this tool in its Rec. # II-1) effectively addresses licensing reviews.

this recommendation as well IV-3 NRC recognition of PIRT SUBSTANTIAL ACTION TAKEN NRC to consider PIRTS as results in licensing

• Industry recommended (7/28/20 appropriate in its licensing reviews workshop) that this be addressed reviews.

in NRC graded review process per II-1 above

• Thermal Modeling, Decay Heat Monitoring, and Fuel Performance PIRTS have been completed and gross rupture PIRT is underway Table 3 - Actions to be addressed through NRC/Industry Dialogue Rec. # Summary Result Path Forward IV-1 NRC and industry to COMPLETE Industry to apply the results of conduct thermal

• Thermal Modeling, Decay Heat the PIRTS in future CoC modeling PIRT Monitoring, and Fuel Performance applications and NRC to apply PIRTs completed the results of the PIRTS in future licensing reviews.

IV-4 Replace 400C cliff SUBSTANTIAL ACTION TAKEN Industry and NRC to re-evaluate edge metric for

• As documented in the 5/13/20 and this limit after completion of the thermal modeling 6/1/20 letters referenced in gross rupture PIRT.

Rec. IV-3 above, this will be accomplished by building on the combined results of the three completed PIRTS (IV-1 above) and the ongoing gross rupture PIRT (Rec. IV-5 below)

IV-5 Develop graded SUBSTANTIAL ACTION TAKEN Industry and NRC to engage on approach to thermal

• NRC has agreed (6/1/20 letter) to the development of this modeling (reinterpret engage in an ongoing PIRT to approach after completion of the gross rupture) address this recommendation. gross rupture PIRT.

PIRT is ongoing.

Ms. Andrea Kock January 14, 2021 Page 5 V-1 Revise Sect. 6.4 of SUBSTANTIAL ACTION TAKEN NRC to reflect new approach in NUREG-1536 to allow

• The new review process NRC has NUREG.

representative vs. developed per III-3 is specific to bounding dose rates radiation dose/shielding and will and credit for design enable this approach analysis V-2 Revise Chapter 6 of SUBSTANTIAL ACTION TAKEN NRC to revise Chapter 6 of the NUREG-2215 based on

• Industry completed NRC requested NUREG as appropriate to reflect experience Operating Experience evaluation lessons learned (including and presented results to NRC in experience with application of 12/16 public meeting the risk tool)

• Risk tool being developed per II-1 will help enable VI-2 Align licensing SUBSTANTIAL ACTION TAKEN Holtec to submit and NRC to approaches for fuel

• NRC approved graded approach to review, under the fee waiver qualification information CoC amendments/applications per granted for activities related to V-1 the White Paper.

• Holtec has committed to submit to NRC a Shielding Method of Evaluation topical report that will substantially improve the manner in which fuel qualification information is addressed VII-1 Align licensing NO ACTION IN 2020 NRC and Industry to engage in approaches for criticality

• Industry and NRC have agreed to further dialogue in 2021.

safety planning dialogue to initiate needed actions VII-2 Develop more realistic NO ACTION IN 2020 NRC and Industry to engage in modeling of fuel

• Industry and NRC have agreed to further dialogue in 2021.

configuration planning dialogue to initiate needed actions VII-3 Redefine gross

• NRC has agreed (6/1/20 letter) to NRC and Industry to develop rupture engage in a PIRT that will begin in new definition upon completion October and be complete by of the gross rupture PIRT.

January 2021 to directly address this recommendation It should be noted that industry considers the clarification requested in Table 2 with respect to NRCs risk tool (Recommendations II-1 and III-3) to be of the upmost importance. This tool has the potential to be among the most valuable products of this effort, however, for this value to be realized, the tool must be transparently

Ms. Andrea Kock January 14, 2021 Page 6 applied and its use visible to industry. It was not clear in our December 17 public meeting specifically how this would be achieved. We request that NRC schedule a public meeting at your earliest convenience so that we may further discuss.

Overall, NRC is to be commended for its hard work and dedication towards achieving needed improvements in dry storage licensing efficiency. This effort has become a notable example of the type of change that is needed if NRC is to truly complete its ongoing transformation to become a modern risk-informed regulator.

Nuclear Materials Safety and Safeguards (NMSS) staff have clearly embraced the objective of former NMSS Office Director Mark Dapas January 15, 2019 memorandum which identified the need for systematic and expanded use of risk and safety insights in decision-making, including the need to appropriately scale the scope of staff review and the level of detail needed from an applicant for licensing decisions.

Industry looks forward to continuing to work with NRC on the implementation of the methods, tools, and approaches that we have developed. Going forward, it is important that we openly discuss and document the specific efficiency improvements which result, and address lessons learned to further refine our efforts. To this end, we recommend that, beginning in July 2021, NRC and Industry convene quarterly progress review and reinforcement meetings.

We are very interested in hearing NRCs perspective on what has been accomplished through this effort. We request that you reply to this letter with your assessment of the results identified in Tables 1-3 above and an indication of your willingness to engage on the recommended path forward. An initial response would be appreciated by February 22, 2021. Please contact me or Mark Richter of my staff (mar@nei.org) with any comments or questions on the content of this letter.

Sincerely, Rod McCullum

Enclosure:

Industry White Paper - Defining Spent Fuel Performance Margins c: Mr. John Lubinski, NRC/NMSS Mr. Christopher Regan, NRC/NMSS/DFM Mr. James Rubenstone, NRC/NMSS/DFM