Text

Nrc/Nei Workshop Master Slides April 13, 2021
	ML21097A245
Person / Time
Site:	Nuclear Energy Institute
Issue date:	04/13/2021
From:	Anton S, Andrew Barto, Csontos A, Elisio D, Jonathan Marcano, Marcano-Lozada J, Richter M, Alexis Sotomayor-Rivera, Waldrop K, Veronica Wilson, John Wise; Electric Power Research Institute, Holtec, NRC/NMSS/DFM/MSB, Nuclear Energy Institute
To:	;
	JMarcano - NMSS/DFM/MSB - 301.4156731
References
	Download: ML21097A245 (63)
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Welcome! The meeting will start soon.

Workshop: Link for Video and Slides (No audio):

Enhancements to https://usnrc.webex.com/usnrc/onsta the Storage Dry ge/g.php?MTID=e64bdf8155a35d4a3 Cask Program ca22497012048d29 Audio Call-in: (888) 282-0567; Passcode: 9824795 1

Fuel Cladding Gross Rupture 2

Introduction and Opening Remarks 3

Spent Nuclear Fuel Performance Margins Workshop Opening Remarks Mark Richter APRIL 13, 2021

Opening Remarks Look how far weve come!

2021 is an important year Moving forward with plans for remaining recommendations Implementation is the key to success Increased safety focus and improved licensing practices will be the measure of our shared success

NRC Considerations on Criticality Recommendations from NEI Whitepaper Andrew Barto Nuclear Analysis and Risk Assessment Branch April 13, 2021 6

Whitepaper Recommendations on Criticality VII-1: Align approaches in criticality safety analyses for dry cask storage systems with current practices in spent fuel pools (full fission product burnup credit, 100% credit for neutron absorber capability).

Fuel Cladding VII-2: Develop a more realistic approach to the modeling of fuel Gross reconfiguration Rupture scenarios in criticality analysis.

VII-3: Develop a safety-focused definition of the term gross rupture through a graded or risk-informed approach that maintains reasonable assurance of adequate protection of the public health and safety as required by 10 CFR Part 72.122h. This definition should be clear and have a well-established basis so that it does not evolve over time.

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Recommendation VII-1 Background on Full Fission Product Burnup Credit:

NUREG-2215 and -2216 recommend crediting 28 actinide and fission product nuclides which are stable or long-lived, not gaseous or soluble, and for which sufficient radiochemical assay data exists for depletion code validation.

o Based on years of research evaluating available radiochemical assay data and approaches for depletion code validation, culminating in NUREG/CR-7108, An Approach for Validating Actinide and Fission Product Burnup Credit Criticality Safety AnalysesIsotopic Composition Predictions o Additional research on critical experiments applicable to spent fuel in storage and transportation casks culminated in NUREG/CR-7109, An Approach for Validating Actinide and Fission Product Burnup Credit Criticality Safety Analyses Criticality (keff ) Predictions o Results from these research efforts were incorporated into ISG-8, Revision 3, subsequently incorporated into the SRPs

NEI 12-16, Guidance for Performing Criticality Analyses of Fuel Storage at Light-Water Reactor Power Plants, endorsed with exceptions in NRC Regulatory Guide 1.240, Fresh and Spent Fuel Pool Criticality Analyses.

o NEI 12-16 not reviewed by NMSS/DFM for applicability to storage and transportation o NEI 12-16 was recently endorsed by NRR in March 2021 8

Recommendation VII-1, Continued Background on Full Fission Product Burnup Credit, continued:

Burnup Credit guidance in NUREG-2215 and -2216 states that additional minor actinides and fission products represent small contribution to keff, which is maintained as an additional margin for depletion uncertainty.

For all nuclides credited in SFP analyses, depletion uncertainty bounded by large margin due to soluble boron loading in PWR pools, or peak reactivity approach in BWR pools, as well as sufficient means to detect and mitigate criticality (compared to storage and transportation scenarios).

Next Step:

Staff are receptive to considering industry proposals for alternative approaches to crediting solid, non-soluble, stable or long lived minor actinides and fission products, provided there is adequate consideration of depletion uncertainties associated with modeling these nuclides.

o Implementation is dependent on staff available resources for review and discussion o Prioritizing ongoing Whitepaper activities o Given that additional minor actinides and fission products represent small contribution to keff collectively, we need to consider the work needed to justify this versus the potential benefits 9

Recommendation VII-1, Continued Background on 100% credit for neutron absorber capability:

NUREG-2215 and -2216 recommend:

o 75% credit for the minimum required poison material in neutron absorbers, due to potential for streaming effects between particles in certain absorber types o Up to 90% credit is recommended when subject to adequate acceptance and qualification testing o 10% margin maintained for potential criticality validation and poison uniformity materials issues o Increase in credit would likely have little impact on keff, but could result in lower required 10B loadings Next Step:

NRC staff considering research effort to evaluate criticality validation and materials issues to see if this amount of margin is warranted o Depending on Division resource availability 10

Recommendation VII-2 Background on Fuel Reconfiguration:

Failed fuel in failed fuel cans are modeled in a conservative manner, given the wide range of fuel conditions expected to be loaded (e.g., fuel fragments, broken rods)

Undamaged fuel, as defined in ISG-1, typically modeled with clad, and with expanded pitch to bound possible reconfiguration scenarios for such fuel Next Steps:

Possibility exists for undamaged fuel to have less bounding representation in cask criticality models from currently accepted approach

NRC staff planning to wait for the results of the Gross Rupture PIRT before deciding on a path forward, since this activity may result in changes to fuel condition definitions 11

Recommendation VII-3 Background on Gross Rupture:

10 CFR 72.122(h)(1) states: The spent fuel cladding must be protected during storage against degradation that leads to gross ruptures or the fuel must be otherwise confined such that degradation of the fuel during storage will not pose operational safety problems with respect to its removal from storage. This may be accomplished by canning of consolidated fuel rods or unconsolidated assemblies or other means as appropriate.

Ongoing Gross Rupture PIRT to develop a safety-focused definition of gross rupture through a graded or risk-informed approach that maintains reasonable assurance of adequate protection of the public health and safety.

Next Step:

Complete the PIRT 12

Next Steps for Discussion With Industry Recommendation VII-1

Fission product burnup credit:

o Staff to consider industry proposals for alternative approaches to crediting minor actinides and fission products.

solid, non-soluble, stable or long lived adequate consideration of depletion uncertainties associated with modeling these nuclides o Dependent on available staff review time - begin after conclusion of ongoing Whitepaper activities

100% credit for neutron absorber capability:

o Research to evaluate criticality validation and materials issues associated with absorber credit o May begin late FY22, provided resources are available 13

Next Steps, continued Recommendation VII-2

Staff to await the results of the Gross Rupture PIRT before deciding on a path forward for fuel reconfiguration in criticality models Recommendation VII-3

Gross Rupture PIRT is ongoing 14

Spent Nuclear Fuel Performance Margins Workshop Criticality APRIL 13, 2021

Defining Spent Fuel Performance Margins

Recommendation VII-1: Align approaches in criticality safety analyses for dry cask storage systems with current practices in spent fuel pools (full fission product burnup credit, 100% credit for neutron absorber capability). Industry and NRC will need to engage in a dialogue to determine the best way to accomplish this.

Recommendation VII-2: Develop a more realistic approach to the modeling of fuel reconfiguration scenarios in criticality analysis.

Industry and NRC will need to engage in a dialogue to determine the best way to accomplish this.

NUREG-2125 - published 2014 Revisiting spent fuel criticality analysis in the accident condition

NUREG-2125 Section 5.6 takes a risk informed view of the potential for criticality in a transport cask accident.

Only scenario with a plausible chance of getting water in the cask. (Other conditions, i.e. normal transport, storage, tip-over, etc. would be far less likely for water intrusion.)

The accident scenario, > 60 mph impact with impenetrable surface followed by submersion in water. The probability of water being below a location of hard rock is very low (0.009 for truck and unknown for rail).

Combined probability is on the order of 10-15.

Seal failure in accident probability is 4x10-10

Cask flooding with failed seal probability is 10-5

Given these extremely low probabilities, it can be deduced that a criticality event is not credible.

Industry Vision

Part 72 is generally aligned with Part 50 for criticality

Dry storage future needs for higher burnup and increased enrichment spent fuel is efficiently managed

Additional conservatisms in dry storage result in similar requirements for dry and wet storage

Criticality concerns only during cask loading in pool

Desired Outcomes

Full burnup credit

Full credit for neutron absorber performance

Reasonable modeling of failed fuel configuration scenarios

Level of staff review and analysis reflects credit commensurate with experience and provides for reasonable assurance of adequate protection of public health and safety (i.e., not absolute assurance)

Integrating the Deliverables In Pool In Storage on Pad In Transit Part 50 governs pool racks Part Part 72 governs Part 71 governs 72 governs cask loading in pool Why is fuel treated differently?

Are Margins consistently understood and applied throughout?

Benefits

Reasonable assumptions for dry storage spent fuel parameters lead to more efficient reviews

Continuity across regulations for spent nuclear fuel results in uniform calculations and a more efficient review process

Improved licensing practices enable increased focus and resources on issues of safety significance

Questions?

Break 23

Graded Approach Norma Garcia-Santos Storage and Transportation Licensing Branch April 13, 2021 24

Background

Purpose:

To streamline the format and content of a storage certificates of compliance (CoCs) by focusing mainly on:

- safety-related items,

- risk-informed content,

- reorganize CoC format,

- remove duplicative items, as appropriate, and

- relocate non-safety related items to other regulatory documents, as appropriate.

Pilot amendment: Amendment 16, standardized NUHOMS HSM cask system

Applicant: TN Americas LLC

Design changes: The applicant did not request design changes to the cask system.

Amendment Effective: September 2020

NRC endorsement of the graded approach: January 2020 This streamlined format allows vendors of spent fuel storage systems to be able to make some non-safety-related changes through the existing regulatory process rather than having to request a new or amended certificate, which would require rulemaking.

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Background===

Concurrently with the graded approach, activities such as the MOE will also impact the content of certificates of compliance.

NRC staff held a workshop in December 2020 seeking feedback from industry on their plans for future use of the graded approach.

Industry expressed interest in the graded approach for future amendments, but did not see the need for additional guidance in the immediate future 26

Next Steps

Planning to evaluate challenges and successes related to the graded approach pilot.

Evaluating the following:

- stakeholder feedback to begin assessing the need and/or timing of guidance updates to incorporate the graded approach

- ways to further communicate the process for submittals using the graded approach methodology

- considering ways to facilitate use of the graded approach

Looking to see if additional clarity in certain areas of the submittal worksheets would be beneficial (what kind / what areas).

How will applications use graded approach criteria?

What other actions could facilitate the use of the graded approach?

27 NUHOMS Horizontal Storage Module

28 Denise Elisio, Licensing, Holtec International Holtec CoC 1014 Reorganization

- UPDATE -

NRC/NEI Workshop 4/13/2021

29 Holtec CoC 1014 Reorganization

Background

RIRP-I-16-01 (2017): NEI proposed an outline for improving the storage CoC format and contents on behalf of the industry

TN Pilot (submitted 2017 - approved 2020): TN submitted a non-technical amendment to a CoC following the guidance in RIRP

NEI Margin White Paper: Recommendation VI-1: CoC holders should amend their CoCs to follow the precedent

Holtec CoC 1014 - Amendment 16 (2021 - ongoing): includes technical changes and a proposed reorganization of the CoC and its appendicies

30 Holtec CoC 1014 Reorganization Reorganization Process Step 1: Reorganized Outline:

Compare current CoC statements,

CoC sections, tables, etc. to the new I. Technology proposed outline and identify what II. Design Features should be retained in the reorganized

Appendix A - Inspections, Tests, and CoC and what should be deleted Evaluations

Appendix B - Technical Specifications

1. Definitions, Use, and Application

2. Approved Contents

3. LCOs and SRs

4. Administrative Controls

31 Holtec CoC 1014 Reorganization Reorganization Process Step 2: Will removing this requirement from Risk Insite - Evaluator should think the CoC/TS result in about subsequent changes to a

A significant increase in the relocated CoC requirement. Specifically, probability or consequences of an ask the question what is the likelihood accident previously evaluated in the and worst possible consequences of a cask FSAR?

future change to this requirement in

The possibility of a new or different the less conservative direction? kind of accident being created compared to those previously evaluated in the FSAR?

A significant reduction in the margin of safety for ISFSI or cask operation?

32 Holtec CoC 1014 Reorganization Holtec CoC 1014 - Amendment 16

This LAR contains proposed technical changes to the existing CoC and its Appendices

It also contains the following documents to support the reorganization:

- Reorganized CoC and Appendices

- Reorganization Tables

- Reorganization Matrix

33 Holtec CoC 1014 Reorganization Holtec Application

Step 2 was only considered for items that did not fit into the proposed outline

CoC Section III added

Code alternative tables retained

Expanded information included in Appendix A Overall, the process took less effort than initially estimated.

Shielding MOE Veronica Wilson Nuclear Analysis and Risk Assessment Branch April 13, 2021 34

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Background===

Currently NRC staff approves contents with respect to shielding design via values of burnup, enrichment and cooling time to satisfy portions of 72.236(a) that normally appear in the technical specifications

- Can be in the form of fuel qualification tables (FQT) and/or correlations

These values are used within shielding demonstration calculations to satisfy 72.236(d) that the shielding features are sufficient to meet the requirements in 10 CFR 72.104 and 72.106

- Within these requirements are an annual dose limit for the controlled area boundary under normal operating conditions and anticipated occurrences and a dose limit under design basis accidents 35

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Background===

Need for Improvement:

CoC applicants have refined their allowable contents for a dry storage system to maximize capacity

- Some systems allow thousands of possible permutations of fuel parameters that can be used to create a single loading pattern for one cask

- Each one of these thousands of possible combinations is designed to have roughly similar performance in terms of dose rate

The problem is that the Tech Specs now include hundreds of pages to specify fuel parameters

Reviewing and approving systems with complex fuel specifications is difficult and time consuming

- The staff has not required specifying fuel in this way

- Staff reviews what is submitted

To alleviate this issue, the staff is seeking a more efficient way that the systems can demonstrate compliance with regulations while maintaining the same level of safety 36

NRC Proposal

NRC is considering acceptance of a Method of Evaluation approach (similar to a COLR approach for reactors) to determine specifications for burnup, enrichment, and cooling time to meet the requirements of 10 CFR 72.236(a)

For example, instead of actual values of burnup, enrichment and cooling time, technical specifications could state that a specific NRC approved method will be used to derive and limit these parameters

- NRC would review and approve the specific method that is referenced in the technical specifications

This approach builds on lessons learned during the Graded Approach (72-1004 Amd. 16) review 37

Next Steps

Holtec has submitted a draft topical report with its approach on the MOE to support a discussion at a pre-application meeting

The public pre-application meeting was held on 3/10/2021

The meeting was successful as it helped the staff better understand Holtecs topical report and staff was also able to communicate areas where more information was needed

Holtec will revise the topical report and submit it to NRC. Date-TBD

If NRC staff approves the topical report, then a vendor can submit a CoC Amendment using the topical report 38

39 Dr. Stefan Anton, VP Engineering, Holtec International SHIELDING MOE TOPICAL REPORT

- UPDATE -

NRC/NEI Workshop 4/13/2021

40 Shielding MOE Topical Report Background (1)

NEI white paper on Spent Fuel Performance Margin (Nov. 2019) identified shielding as one of the areas that would benefit from review of margins.

The corresponding recommendations were placed into Category 3, where changes to NRC guidance was needed. Recommendations in this Category were to be considered at a later date.

However, discussions in early 2020 identified the need to look at this at an earlier date since the potential benefits would be larger than initialy expected. Specifically, it became clear that the still unresolved issue of fuel qualification tables/equations in the CoC could be addressed and this was where progress would be highly desirable.

This subject was subsequently and progressively discussed in several workshops throughout 2020.

41 Shielding MOE Topical Report Background (2)

The main outcome of the interactions throughout 2020 was that the NRC proposed a slightly different approach to satisfy 10CFR72.236(a) and (d) from what was used in the past. Most importantly, the qualification of fuel would be documented in a report external to the FSAR and CoC, and hence changes to the qualified fuel would not require license amendments. This would have to be based on a Topical Report outlining the methodology used in this external report. Hence the term MOE Topical Report.

The industry welcomed this approach and committed to a pilot to put this into practice.

After internal industry discussion, it was proposed in the workshop on 11/6/2020 that one topical report would be submitted by Holtec International. The report would be non-proprietary, reflecting its development as a result of the 2019 NEI fuel margin paper.

42 Shielding MOE Topical Report Current Status

The MOE TR was submitted to NRC as a draft on 1/31/2021.

A public meeting was held on 3/10/2021 to discuss the draft. This meeting was very beneficial in providing significant clarifications to both the industry and NRC staff.

The report is currently being revised and the next document will be an updated draft or final version for submittal (still TBD). After review by the NEI team that authored the margin paper, submittal is planned for mid May.

43 Shielding MOE Topical Report Path Forward

Review / Approval of the TR

License Amendment Request(s) for selected storage systems to reference the TR in the CoC as an acceptable way to define approved content

Qualification report(s) to define acceptable content. These can be generic (covering large range of common fuel, but no unusual types),

or site specific (covering everything present at a site, including anything unusual).

- Qualification reports do not need a license amendment or NRC review and approval

Spent Fuel Storage Job Aid / Risk Tool Alexis Sotomayor-Rivera Nuclear Analysis and Risk Assessment Branch April 13, 2021 44

Background

Spent Fuel Storage Job Aid for Risk Informing Reviews

Support the focus of the review (e.g., the depth of the review) based on risk.

Brings information from the Risk Tool, which includes samples of prior safety evaluations into the licensing process.

Provide a step-by-step resource for the staff to risk-inform technical reviews.

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Background

What it does:

Risk Tool and Job Aid provides the impetus for culture shift for risk to become part of the daily conversation of a review.

Job Aid provides for suggested levels of review based on risk.

A worksheet in the Job Aid provides documentation of risk considerations; this worksheet will be used during the acceptance review and potentially in RAI development.

This worksheet facilitates risk discussions amongst the review team.

The Risk Tool is based on available risk studies, safety margin investigations, selected NRC SERs, and input from NRC Senior Technical Reviewers.

Provides an initial raw risk (on a component-by-component basis) for the reviewer to consider.

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Next Steps The Risk Tool Working Group will:

Begin piloting the use of the Risk Tool and Job Aid.

o On March 8th, the Job Aid and Risk Tool were issued for pilot use.

o During the pilot process, NRC staff will hold a conversation with the applicant on the risk tool results and discuss use of the tool within the acceptance review letter.

Hold a future public meeting after the pilot period to discuss lessons learned and seek feedback from the public on the tool (e.g., 8+

months after the Risk tool pilot period beginning).

After the pilot period, work to incorporate the Job Aid and Risk Tool into Division Instructions.

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Fuel Cladding Gross Rupture John Wise Materials and Structural Branch April 13, 2021 48

Whitepaper Recommendations VII-3: Develop a safety-focused definition of the term gross rupture through a graded or risk-informed approach that maintains reasonable assurance of adequate protection of the public health and safety as required by 10 CFR Part 72.122h. This definition should be clear and have a well-established basis so that it does not evolve over time.

Actions: Ongoing PIRT activities IV-4: Replace 400°C cliff edge metric for thermal modeling of fuel cladding (e.g., one with stepped limits with varying level of rigor in temperature calculations and assumptions review)

Actions: PIRT after completion of gross rupture definition activities Review of EPRI topical report 49

Next Steps

Continue participation in PIRT exercises

Review the EPRI topical report. Staff encourages early communication to understand:

- Approach (e.g., changes to how the role of cladding has traditionally been considered in meeting the regulations, impacts to safety analyses of current licenses)

- Any research that will be relied on to inform the report

- Potential need for rulemaking

- Report schedule and anticipated NRC review timeline

Review the results of the PIRTs, the EPRI topical report, and research activities to explore how NRC guidance and regulations may be improved to ensure that gross rupture is addressed in a manner that is practical, risk-informed, and safety-focused (this is an ongoing activity) 50

Gross Rupture PIRT Update Aladar Csontos, Ph.D Technical Executive Keith Waldrop Principal Technical Leader April 13, 2021 NRC Workshop on Spent Fuel Performance Margins www.epri.com © 2021 Electric Power Research Institute, Inc. All rights reserved. Date: Add submission date and/or revision date & #

Thermal Margins Regulatory Issue Resolution Plan Regulatory Implementation RIRP Recommendations IV 1-5 Goals: Replace current Most efficient regulatory Topical Report:

thermal regulatory limit with Fuel Performance Metrics implementation vehicle a technically defensible pending further discussions; alternative to expand e.g. EPRI Topical Report margins and operational and/or NRC Standard flexibilities with increased Review Plan update safety and cost savings Technical Basis Documents Alternate Fuel Performance NRC/DOE/EPRI Reports PIRT Reports Gross Rupture Expert Panel Metrics Expert Panel Decay Definition of Gross Alternate Fuel Heat Thermal Performance Metrics Rupture Expert Panel PIRT PIRT Fuel Performance Expert Panel PIRT 52 www.epri.com © 2021 Electric Power Research Institute, Inc. All rights reserved.

Gross Rupture PIRT Expert Panel Process Preparation - Steering Committee to:

- Define the problem (e.g., licensing, operational, or programmatic)

- Define the specific objectives

- Identify SME needs and select expert reviewers to participate on panel(s)

- Ensures resources are available; defines schedules and oversees progress Pre-elicitation - Experts Review State of Knowledge:

- Define the scenario(s) and evaluation criterion

- Identify, obtain, and review open-source database

- Identify plausible phenomena and develop questionnaire to frame future discussions Elicitation - Expert Ranking Process:

- Rank importance and provide rationales

- Assess uncertainty for phenomenon (e.g., define gaps)

Documentation - Document PIRT results:

Gross Rupture Pre-Elicitation Activities Pre-PIRT Meeting #1 (12/16/2020):

- Address NRC workshop request to provide industry operating experience

- Example spent fuel characterization procedures and experience Pre-PIRT Meeting #2 (01/28/21):

- Identify scenarios and available information needs for PIRT

- Historical and current regulatory perspectives

- NRC proposed gross rupture evaluation criteria Pre-PIRT Meeting #3 (03/24/21):

- Finalize scenarios and figures of merit

Overall Path Forward Gross Rupture PIRT:

- Pre-PIRT Meetings: Dec 2020-April 2021

- PIRT Meeting: May 2021

- Final PIRT Report: September 2021 Steering Committee Meeting: September 2021

- Update and Path Forward Discussions Alternate Fuel Performance Metrics PIRT (tentative):

- Pre-PIRT Meetings: October 2021

- PIRT Meetings December 2021

- Final PIRT Report: March 2022 Steering Committee Meeting: December 2021

NRC/NEI/EPRI/Industry: Prior Workshop Discussions 01/21/20 Workshop:

- Thermal/Decay Heat Modeling and Fuel/Cladding Performance PIRT results

- Recommendation by PIRT expert panel for Gross Rupture PIRT 03/25/20 Workshop:

- DOE/PNNL perspectives on Thermal Modeling of Commercial Spent Fuel 04/16/20 Workshop:

- Technical Interpretation of Gross Rupture - Historical Perspectives 06/11/20 Workshop:

- Roadmaps and NRC perspectives and safety objective of gross ruptures 06/23/20 Workshop:

- Thermal Margins RIRP Crosswalk, Prioritization, and Links to PIRTs 07/28/20 Workshop:

Summary of Recommendations and Action Items 58

Table with Recommendations, NEI and NRC perspectives Source: Open Package (NRC Response to NEI Letter Dated January 14, 2021, Implementation of the Recommendations of Industrys November 8, 2019 White Paper)

Table 3 - Actions to be addressed through NRC/Industry Dialogue Rec. # Summary Results Path Forward NRC Staff Comments Notes - April 13 Workshop IV-1 NRC and industry to COMPLETE Industry to apply the The NRC agrees with the results. As for path conduct thermal

Thermal Modeling, Decay Heat results of the PIRTS in forward, additional discussion may be modeling PIRT Monitoring, and Fuel Performance future CoC applications warranted. We previously communicated in PIRTs completed and NRC to apply the workshops, that a submittal for results of the PIRTS in endorsement may be appropriate for broad future licensing reviews. applicability, consistency, and transparency (e.g., topical report, industry guidance, etc.)

IV-4 Replace 400C cliff SUBSTANTIAL ACTION TAKEN Industry and NRC to re- The NRC agrees with the results and path edge metric for

As documented in the 5/13/20 and evaluate this limit after forward. The NRC is currently participating thermal modeling 6/1/20 letters referenced in Rec. IV-3 completion of the gross in the EPRI led PIRT on gross rupture.

above, this will be accomplished by rupture PIRT.

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 The NRC agrees with the results and path approach to thermal

NRC has agreed (6/1/20 letter) to engage on the forward. The NRC is currently participating modeling (reinterpret engage in an ongoing PIRT to address development of this in the EPRI led PIRT on gross rupture.

gross rupture) this recommendation. PIRT is ongoing. approach after completion of the gross rupture PIRT.

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Table 3 - Actions to be addressed through NRC/Industry Dialogue V-1 Revise Sect. 6.4 of NUREG- SUBSTANTIAL ACTION TAKEN NRC to reflect new approach The NRC agrees with the results and generally 1536 to allow

The new review process NRC has in NUREG. supports the path forward. In addition to the risk representative vs. developed per III-3 is specific to radiation tool referenced, the NRC staff developed a bounding dose rates and dose/shielding and will enable this method of evaluation approach to shielding credit for design analysis approach analyses which would result in a more performance-based review and would facilitate the use of representative dose rates. NRC is evaluating how this approach can be applied to other technical areas and will incorporate this approach into NRC guidance.

V-2 Revise Chapter 6 of SUBSTANTIAL ACTION TAKEN NRC to revise Chapter 6 of The NRC agrees with the results and the path NUREG-2215 based on

Industry completed NRC requested the NUREG as appropriate to forward. After review of the industry proposed experience Operating Experience evaluation and reflect lessons learned topical report for the implementation of the presented results to NRC in 12/16 public (including experience with Method of Evaluation expected in FY 2021, NRC meeting application of the risk tool) staff will begin planning for updates to NUREG-

Risk tool being developed per II-1 will 2215 (Standard Review Plan for Spent Fuel Dry help enable Storage Systems and Facilities).

VI-2 Align licensing approaches SUBSTANTIAL ACTION TAKEN Holtec to submit and NRC to The NRC agrees with results and path forward.

for fuel qualification

NRC approved graded approach to CoC review, under the fee waiver The NRC will need to evaluate whether the information amendments/applications per V-1 granted for activities related current fee waiver extends to Holtecs future

Holtec has committed to submit to NRC a to the White Paper. topical report if a fee waiver is submitted.

Shielding Method of Evaluation topical report that will substantially improve the manner in which fuel qualification information is addressed 60

Table 3 - Actions to be addressed through NRC/Industry Dialogue VII-1 Align licensing NO ACTION IN 2020 NRC and Industry to The NRC agrees with the result and path approaches for

Industry and NRC have agreed to engage in further forward. NRC proposing a planning public criticality safety planning dialogue to initiate needed dialogue in 2021. workshop in the near- future.

actions VII-2 Develop more realistic NO ACTION IN 2020 NRC and Industry to The NRC agrees with the result and path modeling of fuel

Industry and NRC have agreed to engage in further forward. NRC proposing a planning public configuration planning dialogue to initiate needed dialogue in 2021. workshop in the near- future.

actions VII-3 Redefine gross NRC has agreed (6/1/20 letter) to NRC and Industry to While no characterization of the results rupture engage in a PIRT that will begin in develop new definition was provided in NEIs letter, the NRC October and be complete by January upon completion of the believes, consistent with Rec. IV-4 and IV-5, 2021 to directly address this gross rupture PIRT. that substantial action has been taken recommendation through EPRIs gross rupture PIRT and agrees with the path forward. The current schedule is to complete this work in summer 2021.

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Table 2 - Actions that can be taken by NRC within existing regulations Rec. # Summary Results Path Forward NRC Staff Comments Notes - April 13 Workshop II-1 Graded Approach Review COMPLETE SUBJECT TO CLARIFICATION: After clarifying how regulatory The NRC agrees with the results. As for path Process for CoC

NRC letter (1/24/20) defined licensing transparency will be achieved forward, the NRC developed a risk tool to enhance applications and process expectations for in staffs use of this tool, NRC its safety focus during a CoC application review amendments more risk informed reviews to implement this tool in its and will begin piloting this tool in February/March

NRC developed a risk tool to enable a licensing reviews. timeframe. The NRC is committed to transparency graded review process (12/17/20 and has made the tool publicly available (ADAMS workshop) Accession Number ML20350B659). The NRC is also evaluating how best to engage with an applicant on the results of the risk tool and agrees this should be a topic for a near term future workshop.

III-3 Less detailed reviews COMPLETE SUBJECT TO CLARIFICATION After clarifying how regulatory The NRC agrees with the results and as for path when conservatism is

The NRC licensing process transparency will be achieved forward is evaluating how best to engage with an demonstrated implementations and risk tool (per Rec. # in staffs use of this tool, NRC applicant on the results of the risk tool and agrees II-1) effectively addresses this to implement this tool in its this should be a topic for a near term future recommendation as well licensing reviews. workshop.

IV-3 NRC recognition of PIRT SUBSTANTIAL ACTION TAKEN NRC to consider PIRTS as The NRC agrees with the results. As for path results in licensing reviews

Industry recommended (7/28/20 appropriate in its licensing forward, additional discussion may be warranted workshop) that this be addressed in NRC reviews. on the use of PIRT reports. We previously graded review process per II-1 above communicated in workshops, that a submittal for

Thermal Modeling, Decay Heat endorsement may be appropriate for broad Monitoring, and Fuel Performance PIRTS applicability, consistency, and transparency (e.g.,

have been completed and gross rupture topical report, industry guidance, etc.)

PIRT is underway 62

Public Comments 63

ML21097A245

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