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NUREG/CP-0311, Proceedings of the Information Sharing Workshop on High Energy Arcing Faults (Heafs)
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Issue date:	07/31/2019
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NUREG/CP-0311 Proceedings of the Information-Sharing Workshop on High Energy Arcing Faults (HEAFS)

Office of Nuclear Regulatory Research

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NUREG/CP-0311 Proceedings of the Information-Sharing Workshop on High Energy Arcing Faults (HEAFS)

Manuscript Completed: July 2018 Date Published: July 2019 Prepared by:

G. Taylor K. Hamburger N. Melly K. Miller S. Gardocki T. Boyce Mark Henry Salley, NRC Project Manager Office of Nuclear Regulatory Research

ABSTRACT The U.S. Nuclear Regulatory Commission (NRC), Office of Nuclear Regulatory Research, organized this Information-Sharing Workshop on High Energy Arcing Faults (HEAFs). The workshop took place April 18-19, 2018, at the NRC Headquarters Professional Development Center, Building Three, 11601 Lansdown Street, Rockville, MD. The workshop had the following four objectives:

(1) Inform interested stakeholders about the status of PRE-GI-018 and related research.

(2) Review and resolve public comments received on the phase II draft test plan.

(3) Solicit and review information from industry partners regarding common equipment types and configurations to inform future testing.

(4) Provide an opportunity for public feedback on future testing.

The workshop was a Category 3 public meeting and open to the public for participation. The NRC broadcasted the meeting via webinar to encourage participation among interested parties for whom travel was not possible. The agency coordinated the workshop with the Electric Power Research Institute (EPRI) and the National Fire Protection Association (NFPA). The organizers advertised the workshop at recent nuclear industry information forums and during NRC public meetings related to fire protection. The workshops technical topics focused on HEAF hazards and recently completed and ongoing research initiatives. The workshop also covered the NRCs Generic Issues (GI) program as it relates to the aluminum HEAF issue. This proceedings report documents the recommendations and insights from the session presentations and follow-on discussions.

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FOREWORD The U.S. Nuclear Regulatory Commission (NRC) values the technical views and inputs from all stakeholders in the development of agency research projects. The research on high energy arcing faults (HEAFs) is no different. The need for the research is driven by the analysis of the most recent U.S. and international nuclear power plant (NPP) fire event data and operating experience, which has identified HEAF events as a non-negligible fire hazard. This HEAF operational experience illustrates that significant damage may occur during the event.

Experimental results have identified that the involvement of aluminum components during a HEAF may increase the hazard potential. Safe nuclear operation depends on engineers, operators, and probabilistic risk assessment (PRA) practitioners understanding the risk potential of a HEAF and preventing the event or protecting important safety systems, structures, and components from its effects.

This report documents the presentations and discussions conducted during a 2-day public workshop held in the spring of 2018. The NRC plans to use the information gained during the workshop to help finalize its test plans and inform the agency decision-making process. The staff also believes the workshop equally benefitted the participating stakeholders by providing them with the most current information available from the NRC on this matter.

This report continues to build upon previous U.S. and international HEAF work. This research will advance the understanding of this complex phenomenon and its impact on safety. I hope this work will ultimately be used to make a positive contribution to nuclear power plant fire safety.

Mark Henry Salley, P.E.

Chief, Fire and External Hazards Analysis Branch Office of Nuclear Regulatory Research U.S. Nuclear Regulatory Commission June 26, 2018 Rockville, MD v

TABLE OF CONTENTS ABSTRACT ............................................................................................................................. iii FOREWORD .............................................................................................................................. v LIST OF TABLES ........................................................................................................................ ix EXECUTIVE

SUMMARY

............................................................................................................. xi ACKNOWLEDGMENTS ............................................................................................................. xv ABBREVIATIONS AND ACRONYMS ..................................................................................... xvii 1 INTRODUCTION .............................................................................................................. 1-1 1.1 Background........................................................................................................... 1-1 1.2 About This Report ................................................................................................. 1-2 2 WELCOME AND OPENING ............................................................................................ 2-1 2.1 Workshop Opening ............................................................................................... 2-1 2.1.1 Discussion ............................................................................................ 2-1 2.1.2 Presentation Slides .............................................................................. 2-2 2.2 Workshop Introduction and Objectives ................................................................. 2-4 2.2.1 Discussion ............................................................................................ 2-4 2.2.2 Presentation Slides .............................................................................. 2-5 3 REVIEW OF PHASE I HEAF RESEARCH ...................................................................... 3-1 3.1 Review of Phase I HEAF Research ...................................................................... 3-1 3.1.1 Discussion ............................................................................................ 3-2 3.1.2 Presentation Slides .............................................................................. 3-3 4 THE GENEREIC ISSUE PROCESS AND PILOT PLANTS ............................................ 4-1 4.1 The Generic Issue Process .................................................................................. 4-1 4.1.1 Discussion ............................................................................................ 4-1 4.1.2 Presentation Slides .............................................................................. 4-2 4.2 Aluminum HEAF PRE-GI-018 ............................................................................... 4-8 4.2.1 Discussion ............................................................................................ 4-8 4.2.2 Presentation Slides ............................................................................ 4-10 4.3 Pilot Plants .......................................................................................................... 4-15 4.3.1 Discussion .......................................................................................... 4-15 4.3.2 Presentation Slides ............................................................................ 4-18 5 DEFINING THE HAZARD ................................................................................................ 5-1 5.1 Definitions of Energetic Electrical Faults .............................................................. 5-1 5.1.1 Discussion ............................................................................................ 5-1 5.1.2 Presentation Slides .............................................................................. 5-3 6 SMALL-SCALE TESTING AND PROBABILISTIC RISK ASSESSMENT MODELING IMPLICATIONS ........................................................................................... 6-1 6.1 Small-Scale Testing at Sandia National Laboratories .......................................... 6-1 6.1.1 Discussion ............................................................................................ 6-1 vii

6.1.2 Presentation Slides .............................................................................. 6-3 6.2 Probabilistic Risk Assessment Modeling Implications ........................................ 6-10 6.2.1 Discussion .......................................................................................... 6-10 6.2.2 Presentation Slides ............................................................................ 6-11 7 NATIONAL FIRE PROTECTION ASSOCIATION PERSPECTIVE ................................. 7-1 7.1 Perspective from the National Fire Protection Association ................................... 7-1 7.1.1 Discussion ............................................................................................ 7-1 7.1.2 Presentation Slides .............................................................................. 7-2 8 ELECTRIC POWER RESEARCH INSTITUTE PERSPECTIVE ...................................... 8-1 8.1 Perspective from the Electric Power Research Institute ....................................... 8-1 8.1.1 Discussion ............................................................................................ 8-1 8.1.2 Presentation Slides .............................................................................. 8-3 9 PHYSICAL TESTING AND FAILURE RATES ................................................................ 9-1 9.1 Physical Testing and Failure Rates ...................................................................... 9-1 9.1.1 Discussion ............................................................................................ 9-1 9.1.2 Presentation Slides .............................................................................. 9-2 10 TEST PARAMETER AND EQUIPMENT SELECTION .................................................. 10-1 10.1 Test Parameter and Equipment Selection .......................................................... 10-1 10.1.1 Discussion .......................................................................................... 10-1 10.1.2 Presentation Slides .......................................................................... 10-10 11 DRAFT TEST PLAN AND COMMENT RESOLUTION.................................................. 11-1 11.1 Review of Phase II Draft Test Plan and Comment Resolution ........................... 11-1 11.1.1 Discussion .......................................................................................... 11-1 11.1.2 Presentation Slides ............................................................................ 11-3 12 WORKSHOP WRAPUP,

SUMMARY

OF RECOMMENDATIONS, AND FOLLOW-UP .................................................................................................................. 12-1 12.1 Conclusion of Workshop ..................................................................................... 12-1 12.2 Summary of Recommendations ......................................................................... 12-1 12.3 Summary of Follow-Up Actions .......................................................................... 12-2 13 REFERENCES ............................................................................................................... 13-1 APPENDIX A DRAFT LARGE-SCALE TEST PLAN AND COMMENTS ................................ A-1 APPENDIX B REVISED LARGE-SCALE TEST PLAN ........................................................... B-1 APPENDIX C NEEDS AND OBJECTIVES .............................................................................. C-1 APPENDIX D DRAFT SCMALL-SCALE TEST PLAN AND COMMENTS .............................. D-1 viii

LIST OF TABLES Table 10-1 Summary of Parameter Ranking from Workshop Participants ............................. 10-7 Table 12-1 Summary of Workshop Recommendations .......................................................... 12-1 Table 12-2 Summary of Followup Actions .............................................................................. 12-2 ix

EXECUTIVE

SUMMARY

PRIMARY AUDIENCE:

Generation facility staff, fire protection engineers, electrical engineers, and probabilistic risk assessment (PRA) practitioners who are responsible for fire protection programs, electrical equipment operation and maintenance, and associated duties involving the hazard assessment of fire and explosions caused by energetic electrical faults.

SECONDARY AUDIENCE:

Engineers, reviewers, utility managers, and other stakeholders who conduct, review, or manage protection programs and need to understand the U.S. Nuclear Regulatory Commission (NRC) research and planned research related to energetic electrical faults.

KEY RESEARCH QUESTION:

How can the NRC ensure that future research programs on the aluminum high energy arcing faults (HEAF) hazard accurately reflect plant conditions and will produce usable results?

RESEARCH OVERVIEW:

Energetic electrical faults can result in explosions, electrical arcing, fire, ionized gases, and smoke, prompting collateral damage to adjacent equipment and causing latent failures. The characteristics of these failures differ from those of the traditional fire protection hazard assessment, including the bypass of the fire ignition and growth stages; rapid propagation of the fire to other equipment and across vertical fire barriers; power system designs that are vulnerable to station blackout; failed fire-suppression attempts with dry chemicals and the need to use water; longer restoration time to recover; and unexpected challenges to operator response from event byproducts (smoke and conductive gases). These highly energetic events that have the potential to impact plant safety are commonly referred to as High Energy Arcing Faults (HEAFs).

NRC regulations, regulatory guidance, and defense-in-depth design philosophy exist to provide reasonable assurance of adequate protection to public health and safety from the consequences of fires that may occur in a nuclear facility. In the early 2000s, the NRC investigated the insights gained from fire incidents and began an international collaborative effort to better understand operating experience as it relates to fire safety. This collaboration resulted in a series of tests conducted in the United States between 2014 and 2017 to support revisions and improvement to existing fire risk methods. The results demonstrated a unique failure mode for electrical equipment that contained aluminum components, which displayed more damage than revealed in tests conducted on equipment that did not contain aluminum.

These insights prompted the NRC and its international research partners to pursue additional testing.

The NRC issued Information Notice 2017-04, High Energy Arcing Faults in Electrical Equipment Containing Aluminum Components, dated August 21, 2017, to alert addressees of the test results and related operating experience. The NRC staff also proposed this potential safety issue as a generic issue (GI) (PRE-GI-018). In order to adequately assess PRE-GI-018, the NRC needed additional information and decided to hold a workshop to communicate this issue and obtain feedback and information from stakeholders.

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The motivation for holding this workshop was to communicate the NRCs past and planned actions related to the HEAF hazard involving aluminum components. Additionally, the NRC sought feedback from stakeholders to support realistic and representative test conditions to ensure the efficient and effective use of NRC resources as the agency assesses the impact of HEAFs involving aluminum components. The workshop objectives were to (1) inform interested stakeholders about the status of PRE-GI-018 and related research, (2) review and resolve public comments received on the phase II draft test plan, (3) solicit and review information from industry partners regarding common equipment types and configurations to inform future testing, and (4) provide an opportunity for public feedback on future testing. In particular, the technical issues focused on the test parameters that influence the HEAF phenomena, and many discussions during the workshop focused on realistic and representative parameter ranges and nuclear power plant electrical system configurations.

The NRC staff from the Office of Nuclear Regulatory Research organized the workshop in collaboration with the Electric Power Research Institute (EPRI) and the National Fire Protection Association (NFPA). Staff from DNV GL, the National Institute of Standards and Technology (NIST), and Factory Mutual (FM) also provided feedback and direction for organization of the workshop. The NRC welcomed the public to attend and observe this Category 3 public meeting and posting workshop information on the agencys Public Meeting website. About 30 workshop registrants attended the workshop in person. In addition, approximately 33 individuals participated in the workshop via a webinar advertised on the NRC Public Meeting website.

KEY FINDINGS:

In the opening session, the NRC presented the expected outcomes of the workshop. Next, an introduction session welcomed the participants and identified the workshop purpose, objectives, and agenda and emphasized the NRCs safety mission. This was followed by a presentation that reviewed past agency efforts and research related to the HEAF hazard. Following this presentation, the NRC discussed the GI program and gave a presentation on the status of PRE-GI-018 related to the aluminum HEAF issue. Before concluding the morning sessions, presenters spoke about the development of HEAF definitions, small-scale testing, and risk assessment modeling implications. The afternoon sessions focused on research undertaken outside the NRC. This included presentations from the NFPA, EPRI, and DNV GL. The second day of the workshop included extensive discussion among the participants related to the parameters and test configurations that would support realistic and representative configurations to characterize the HEAF hazard and develop data to support the assessment of the HEAF hazard as it relates to the influence of aluminum components. Part of this discussion allowed for voluntary participation in ranking various parameters for their importance in influencing the HEAF phenomena. The NRC and partners could use results from this ranking to support test plan revisions and experimental configurations during future testing. The final sessions of the workshop revolved around the draft full-scale testing being pursued as an international initiative under the Nuclear Energy Agency (NEA) / Organisation for Economic Co-Operation and Development (OECD). The final session focused on a presentation of the draft test plan and resolution of comments received during the public comment period.

As a result of the workshop, the NRC identified several recommendations and follow-up actions, including the following:

improvements to project tracking and task dependencies xii

NRC expectations and schedule related to the pilot plant initiative to support the assessment stage of the GI program suggestion to perform a literature search to allow for better communication and basis for specific aspects of the proposed testing proposed changes to testing configurations and parameters follow-on interactions with stakeholders to communicate findings in a timely manner definitions of the hazard and associated frequencies that would support test result applicability to ensure consistent treatment of the hazard in a risk assessment WHY IT MATTERS:

This report provides recommendations to assist the NRC staff and stakeholders in performing needed research and work to assess the impact of aluminum components on the HEAF hazard and the assessment of that hazard related to plant safety.

HOW TO APPLY RESULTS:

Engineers conducting research related to this topic should focus on Chapters 3-8 and 10.

Users of this report are also encouraged to consult the reference material identified in Section 1.3 and included in the companion DVD.

LEARNING AND ENGAGEMENT OPPORTUNITIES:

Users of this report may be interested in the annual fire PRA training, Module III, Fire Hazard Analysis, sponsored jointly between EPRI and the NRC Office of Nuclear Regulatory Research.

In addition, numerous commercial training opportunities are available related to the analysis of arc flash hazards for personnel safety.

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ACKNOWLEDGMENTS The U.S. Nuclear Regulatory Commission acknowledges and appreciates the many people and organizations that supported the Information-Sharing Workshop on High Energy Arcing Faults (HEAFs). Those who attended that workshop in person and via the webinar provided exceptional feedback and included the following:

Ashley Lindeman (EPRI) Donna Gilmore Brenda Simril (TVA) Marvin Lewis Robert Rhodes (Duke Energy) Marc Janssens (SWRI)

Rob Cavedo (Exelon) Dane Lovelace (Jensen Hughes)

Francisco Joglar (Jensen Hughes) Chris Riedl (TVA)

Daniel Funk (Jensen Hughes) Victor Savulyak (DNV GL)

Jana Bergman (Curtiss Wright) Robert Taylor (BSI)

Francesco Pellizzari (EPM) Jeffrey Voskuil (Entergy)

Stephen Turner (Consultant) Sandy Naccarato (Southern Company)

Scott Bareham (NIST) JongSeuk Park (KINS)

Rodney Pletz (AEP) Joshua Ross (First Energy Corporation)

Mathew Merriman (Appendix R Solutions) Neal Simmons (Duke Energy)

Beth Wetzel (TVA) Keith Vincent (FPL)

Jens Alkempes (FM Global) Kiang Zee (Jensen Hughes)

Sujit Purushothaman (FM Global) Preston Cooper (TVA)

Thomas Shudak (NPPD) Mike Franovich (NRC)

Kenneth Fleisher (EPRI) Steven Alferink (NRC)

Anthony Putorti (NIST) Philipp Braaten (NRC)

Kazimierz Leja (Exelon) William Monk (NRC)

Victoria Anderson (NEI) Tomy Nazario (NRC)

Jack Campellone (Duke Energy) Sam Graves (NRC)

Alex Feldman (DNV GL) Gregory Werner (NRC)

Robert Egli (TVA) David Stroup (NRC)

Scott Groesbeck (DP Engineering) Robert Daley (NRC)

Mark Hulet (APS) Tomy Nazario (NRC)

Young Jo (Southern Company) Bas Verhoeven (DNV GL)

David Lochbaum (UCS) Frank Cielo (DNV GL)

Bob Meyer Alice Muna (SNL) xv

ABBREVIATIONS AND ACRONYMS AC alternating current ADAMS Agencywide Documents Access and Management System AL aluminum AT auxiliary transformer AWG American Wire Gauge BSI Brendan Stanton Inc.

CCDP conditional core damage probability CDF core damage frequency CFD computational fluid dynamics CFR Code of Federal Regulations CIGRE International Council on Large Electric Systems CSNI Committee on the Safety of Nuclear Installations DC direct current EELS electron energy loss spectroscopy ERFBS electric raceway fire barrier systems EPRI Electric Power Reseach Institute EDXA energy dispersive x-ray analysis FAQ frequently asked question GDC general design criterion/criteria GI generic issue GIRP Generic Issue Review Panel GSU generator step-up HEAF high energy arcing fault HGL hot gas layer HRR heat release rate IEC International Electrotechnical Commission IEEE Institute of Electrical and Electronics Engineers IN information notice ISO International Organization for Standardization KINS Korea Institute of Nuclear Safety LER licensee event report LV low voltage MOU memorandum of understanding MV medium voltage NEA Nuclear Energy Agency NEI Nuclear Energy Institute NFPA National Fire Protection Association NIST National Institute of Standards and Technology NPP nuclear power plant xvii

NRC U.S. Nuclear Regulatory Commission NRR Office of Nuclear Reactor Regulation NSP non-suppression probability OECD Orginisation for Economic Co-operation and Development OpE or OPEX operating experience OSHA Occupational Safety and Health Administration PIRT phenomena identification and ranking table PRA probabalistic risk assessment RES Office of Nucear Regulatory Research ROI Regulatory Office Implementation RTPC Research and Testing Planning Committee SEM scanning electron microscopy S/NRA/R Secretariat of Nuclear Regulation Authority (Japan)

SNL Sandia National Laboratories SPAR standardized plant analysis risk STL short-circuit testing liason SWRI Southwest Reasearch Institute T&D transmission and distribution TPP test procedure and protocol UCS Union of Concerned Scientists ZOI zone of influence xviii

1 INTRODUCTION

1.1 Background

The U.S. Nuclear Regulatory Commission (NRC) fire protection requirements in Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of Production and Utilization Facilities, (Ref. 1) and the supporting guidance address fire from energetic faults.

For example, 10 CFR Part 50, Appendix A, General Design Criteria for Nuclear Power Plants, General Design Criterion 3, Fire Protection, requires that structures, systems, and components important to safety be designed and located to minimize, consistent with other safety requirements, the probability and effects of fires and explosions. The requirements in 10 CFR 50.48, Fire Protection, state that each operating nuclear power plant must have a fire protection plan that satisfies General Design Criterion 3 of Appendix A to 10 CFR Part 50.

Section 4.1.3.6, Electrical Cabinets, of NRC Regulatory Guide 1.189, Fire Protection for Operating Nuclear Power Plants, Revision 3, issued February 2018 (Ref. 2), states that electrical cabinets present an ignition source for fires and a potential for explosive electrical faults that can result in damage not only to the cabinet of origin, but also to equipment, cables, and other electrical cabinets in the vicinity of the cabinet of origin. Regulatory Guide 1.189 also states that fire protection systems and features provided for the general area containing the cabinet may not be adequate to prevent damage to adjacent equipment, cables, and cabinets following an energetic electrical fault; therefore, cabinets with voltages of 480 volts and above should have adequate spatial separation or substantial physical barriers to minimize the potential for an energetic electrical fault to damage adjacent equipment, cables, or cabinets important to safety.

Fire probabilistic risk assessments (PRAs) include methods to characterize the high energy arcing fault (HEAF) hazard, as documented in Electric Power Research Institute (EPRI)

Technical Report (TR) 1011989/NUREG/CR-6850, EPRI/NRC-RES Fire PRA Methodology for Nuclear Power Facilities, issued September 2000 (Ref. 3). Volume 2 of NUREG/CR-6850 contains the guidance for electrical enclosures (Appendix M), and Supplement 1 (Ref. 4) contains guidance for bus ducts (Chapter 7). Both methods provide a bounding approach to quantifying the HEAF hazard; that is, they assume physical damage zones based on available operating experience that demonstrated extensive damage to surrounding equipment. Although the details of each method are documented in the reference identified above, the methods generally assume all components and systems within the physical damage zone are ignited and are unable to perform their intended design function. Accordingly, these methods were considered conservative and bounding for future arcing fault events.

Starting in the mid-2000s, the NRC began international collaboration to better understand the HEAF phenomena and advance the existing state of knowledge and fire PRA methods. This collaboration was facilitated through the Nuclear Energy Agency (NEA)/Organisation for Economic Co-operation and Development (OECD), of which the NRC is a member. Under an OECD FIRE data exchange project, member countries share operating experience related to fires occurring at nuclear facilities in 12 countries. As part of the analysis of this data, a non-negligible number of reportable events with non-chemical explosions and rapid fires resulting from high energy arcing faults (HEAF) was observed (Ref. 5). As a result of this observation and in alignment with the major goals of the NEA/OECD task to develop a correlation for predicting damage, establishing input data, and establishing boundary conditions for more detailed modeling, the member countries recommended performance of a series of experiments.

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From 2014 to 2016, the NRC led an international experimental program, as documented in NEA/CSNI/R(2017)7, Report on the Testing Phase of High Energy Arcing Fault Events (HEAF)

Project, issued May 2017 (Ref. 6). This report documents 26 HEAF tests that were performed on a variety of donated electrical equipment. One significant finding from this work was that HEAFs involving aluminum components may result in greater damage and different failure modes than HEAFs that do not contain aluminum. Based on these findings, the international group recommended additional testing.

In 2016, based on the results from testing indicating that the current fire PRA methodology may not be bounding, the NRC staff proposed a potential safety concern related to HEAFs involving aluminum as an issue for the NRCs Generic Issue (GI) program. Following an initial review and a formal screening review, a Generic Issue Review Panel (GIRP) determined that the proposed issue met all seven screening criteria of the GI program and recommended that the issue be moved into the assessment stage of the GI program. As part of that assessment stage, a number of actions were identified that will be performed to assess the potential risk impact associated with HEAFs involving aluminum. These actions include, in part, additional testing.

These findings also prompted the NRC staff to reevaluate operating experience and identify any HEAF events that involved aluminum components. The staff documented the results of this effort in Information Notice (IN) 2017-04, High Energy Arcing Faults in Electrical Equipment Containing Aluminum, issued August 2017 (Ref. 7). This IN summarizes the test results where damage states exceeded existing guidance and involved aluminum components. Additionally, the IN summarizes six HEAF events from operating experience that involved aluminum components and provides a qualitative description of those events.

Given the NRCs desire to understand the HEAF hazard involving aluminum and ensure adequate protection of public safety, external stakeholders have developed information to better understand and model the hazard. These initiatives include NRC Frequently Asked Question (FAQ)17--0013, High Energy Arcing Fault (HEAF) Non-Suppression Probability (NSP), dated March 21, 2017 (Ref. 8). EPRI has also developed two whitepapers (Refs. 9, 10) that provide an overview of nuclear power plant electrical distribution systems and characterize operating experience and testing.

In 2017, the NRC staff began formalizing an international agreement to perform a Phase II testing campaign to address knowledge gaps and further explore the impact aluminum plays in HEAF events. The NRC issued a draft test plan for public comment in the Federal Register on August 2, 2017. However, in order to ensure that U.S. interests are met and the program is performed in an efficient and effective manner, the NRC staff decided that additional stakeholder interactions and feedback were warranted. As such, it was suggested that an HEAF workshop be held as the forum for this interaction. The workshop took place April 18-19, 2018, at the NRC Headquarters offices in Rockville, MD. This report documents that workshop, the discussions held, and the feedback received.

1.2 About This Report This report is a collection of the materials presented at the 2-day workshop held April 18-19, 2018. The workshop transcripts (Refs. 11, 12) are available in the NRCs Agency-wide Documents Access and Management System (ADAMS) under Accession Nos.

ML18114A817 and ML18114A818. The companion DVD also includes these transcripts.

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In addition to the workshop materials and transcripts, the companion DVD includes a variety of documents related to the HEAF research program, including the following:

test footage and data from Phase 1 testing FAQs, INs, and GI communications related to HEAF licensee event reports (LERs) from relevant HEAF events small- and large-scale draft test plans and comments This report documents the material sequentially as it was presented during the workshop. For each session, this report includes a brief summary of any formal presentation, followed by documentation of discussion points, recommendations from those discussions, and any follow-up action items. Each chapter ends with the slide deck as presented, reproduced as embedded images.

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