ML21231A212

NRC-2018-000831 - Resp 14 - Interim, Agency Records Subject to the Request Are Enclosed, Part 3 of 3

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Hiser, Matthew Wed, 31 May 201719:55:53 +0000 Frankl, Istvan RE: Workshop Summary Report Note to requester: The attachment is immediately following this email.

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Harvesting Workshop Summary Report draft 5-26-17 (IF) mah incorp.docx Hi Steve, Thank you for reviewing and providing input. I just wanted to share responses for a couple comments and questions.

Thanks!

Matt Matthew Hiser Materials Engineer US Nuclear Regulatory Commission I Office of Nuclear Regulatory Research Division of Engineering I Corrosion and Metallurgy Branch Phone: 30 l-415-24541 Office: TWFN I 0D62 Matthew.Hiser@nrc.gov From: Frankl, Istvan Sent: Tuesday, May 30, 2017 5:55 PM To: Hiser, Matthew

Subject:

RE: Workshop Summary Report Thanks Matt.

This is a well-written report. Please see my attached editorial revisions and comments.

Steve From: Hiser, Matthew Sent: Friday, May 26, 2017 9:18 AM To: Purtscher, Patrick <Patrick.Purtscher@nrc.gov>; Tregoning, Robert <Robert.Tregoning@nrc.gov>;

Hull, Amy <Amy.Hull@nrc.gov>; Frankl, Istvan <lstvan.Frankl@nrc.gov>

Subject:

RE: Workshop Summary Report I have incorporated significant input from Amy and Pat on the Harvesting Workshop Summary Report.

The latest version of the report is attached.

My plan is to send this complete draft to the workshop participants for review and comment by Wednesday, May 31. Please provide any further input or comments by next Wednesday to be incorporated in the draft sent to workshop participants.

I will ask for feedback from workshop participants by the end of June with the intent to finalize this summary report by mid-July.

Please let me know if you have any questions or suggestions on how to best move this effort forward.

Thanks!

Matt

Ex-Plant Materials Harvesting Workshop Summary Report Workshop held on March 7-8, 2017 at NRC headquarters in Rockville, MD NRC staff: Matthew Hiser, Patrick Purtscher, Amy Hull, Robert Tregoning

Table of Contents Background................................................................................................................................................... l Objective and Approach............................................................................................................................... 1 Workshop Organization and Sessions.......................................................................................................... 2 Summary of Workshop Discussion............................................................................................................... 2 Session 1. Motivation for Harvesting........................................................................................................ 2 Presentation Summaries...................................................................................................................... 2 Discussion Summary............................................................................................................................. 3 Session 2. Technical Data Needs for Harvest ing....................................................................................... 3 Presentation Summaries......................................................................................................................3 Discussion Summary............................................................................................................................. 5 Session 3. Sources of Materials................................................................................................................ 6 Presentation Summaries...................................................................................................................... 6 Discussion Summary............................................................................................................................. 9 Session 4. Harvesting Experience: Lessons Learned and Practical Aspects.............................................. 9 Presentation Summaries...................................................................................................................... 9 Discussion Summary........................................................................................................................... 13 Session 5. Future Harvesting Program Planning..................................................................................... 13 Presentation Summary....................................................................................................................... 13 Discussion Summary........................................................................................................................... 13 Key Takeaways from Workshop................................................................................................................. 14 Session 1. Motivation for Harvesting...................................................................................................... 14 Session 2. Technical Data Needs for Harvest ing..................................................................................... 14 Session 3. Sources of Materials.............................................................................................................. 14 Session 4. Harvesting Experience: Lessons Learned and Practical Aspects............................................ 16 Session 5. Future Harvesting Program Planning..................................................................................... 16 Action Items and Next Steps...................................................................................................................... 16 References to Previous Harvested Materials Research.............................................................................. 17 Appendix I Workshop Participants............................................................................................................. 19 Appendix II Workshop Agenda................................................................................................................... 20 Appendix Ill Harvesting Opportunit ies in Germany.................................................................................... 22

List of Figures Figure 1 Schematic of Westinghouse ex-vessel neutron dosimetry (EVND)................................................ 5 Figure 2 Nuclear Fuels and Materials Library (NFML) Database Design............................*.......................... 7 Figure 3 Zorita Internals Research Project (ZIRP) Timeline........................................................................ 10 List of Tables Table 1 Ongoing Harvesting Programs..............................................................................*........................ 15 Table 2 Potential Future Sources for Harvesting........................................................................................ 15 iii

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Background===

On March 7-8, 2017, t he Office of Nuclear Regulatory Research of the United States Nuclear Regulatory Commission (NRC) hosted a 2-day workshop on the topic of "Ex-Plant Mat erials Harvesting." NRC staff worked in close coordination with staff from t he U.S. Department of Energy (DOE) and the Electric Power Research Institute (EPRI) to plan and arrange the workshop.

~he decision to organize this workshop was driven by developments in the U.S. and global nuclear industry. In the U.S., there is strong interest in extending plant lifespans through subsequent license renewal (SLR) from 60 t o 80 years. Extended plant operation and SLR raise a number of technical issues that may require further research to understand aging mechanisms, which may benefit from harvesting.

Meanwhile, in recent years, a number of nuclear plants, both in the U.S. and internationally, have shut dow n or announced plans to shut down. Unlike in the past when there were very few plants shutting dow n, these new developments provide opportunities for harvesting components that were aged in representative light water reactor (LWR) environments. In a related development, economic challenges for t he nuclear industry and limited government spending have limited the resources available to support new research, including harvesting programs. Given this constrained budget environment, aligning interests and leveraging wit h other organizations is important to allow maximum benefit and value for future research programs.I Objective and Approach The objective of the workshop was to generat e open discussion of all aspects of ex-plant materials harvesting, including:

1. Deciding whether to harvest,

2.

Planning and implementing a harvesting program,

3.

Using t he harvested materials in research programs.

Through presentations and open discussion, t he workshop was organized to allow for all participants t o be better informed of the benefits and challenges of harvest ing as well as to identify pot ent ial areas of common interest for fut ure harvesting programs. Workshop sessions were aligned in broad t opics to cover all aspects of harvesting that allowed t he participants to drive the discussion.

To help accomplish the workshop objectives, the workshop organizers intentionally sought a diverse group of participants. There are a large number of decommissioning plants and interested researchers outside the U.S., so the organizers focused on outreach to international participants through organizations such as the International Atomic Energy Agency (IAEA), Organization for Economic Cooperation and Development Nuclear Energy agency (OECD/NEA), and existing professional contacts.

In addition, a key goal for this workshop was to capture the broader practical perspective from plant owners and decommissioning companies, which are vital to any successful harvesting p rogram, but may sometimes be overlooked in researcher-driven discussions. Workshop part icipants were also diverse in terms of technical area of focus, with metal components such as the reactor pressure vessel (RPV) and internals being discussed along with concrete and electrical components. The final list o f workshop participants can be found at the end of this report in Appendix I.

4 Commented [FIi]: Is there any Info from the related PUM abstract t hat can be borrowed/ added to this paragraph or other applicable section?

I actually used this paragraph as a starting point for the PLiM abstract. I don't want to make them too similar, since this is ostensibly a non-public workshop summary for participants, while the PLIM Is In the open literature. Not that the message is very different, but I'd rather t hem be somewhat different.

Workshop Organization and Sessions The workshop was held at NRC headquarters in Rockville, MD. Due to limited space in t he meeting room and the need for a limited group size for discussion, a webinar was used to allow remote observers to benefit from the workshop. Workshop sessions were organized topically with about half the time dedicated to presentations and the remaining time set aside for discussion. Presentations were solicited from participants to cover a range of perspectives and technical areas. The final workshop agenda can be found at the end of this summary report in Appendix II.

The workshop was organized into five sessions as follows:

Session 1. Motivation for Harvesting Session 2. Technical Data Needs for Harvesting Session 3. Sources of Materials Session 4. Harvesting Experience: Lessons Learned and Practical Aspects Session 5. Future Harvesting Program Planning Summary of Workshop Discussion The subsections below will summarize the presentations and discussion in each session and highlight the key takeaways from the session.

Session 1. Motivation for Harvesting Session 1 focused on the motivation for harvesting and why workshop participants are interested in harvesting. As shown in Appendix II with presentation t itles, speakers for this session included:

Richard Reister from DOE, Sherry Bernhoft from EPRI, Robert Tregoning from NRC, Uwe Jendrich from the Gesellschaft fur Anlagen-und Reaktorsicherheit (GRS) in Germany, and Taku Arai from the Central Research Institute of the Electric Power Industry (CRIEPI) in Japan.

Presentation Summaries DOE described the role of harvesting within the Light Water Reactor Sustainability (LWRS) Program, including the benefits and challenges associated with harvesting. Benefits include the opportunity to fill knowledge gaps where there is limited data or experience and to inform degradation models with data from actual plant components. Challenges include cost, complexity, scheduling, logistics, limited opportunities, acquiring sufficient material pedigree information, and potential negative results impacting operating plants.

EPRI discussed the role of harvesting within the context of aging management for Long-Term Operations (LTO), including their experience from past ha,rvesting programs and criteria for future harvesting. Their experience emphasized the challenges of cost, schedule, logistics, complicated cont racting and acquiring material pedigree information. EPRl's criteria for harvesting focus on demonstrating value to their members by addressing a prioritized need that cannot be addressed through other means. For EPRI, a well-developed project plan that covers funding, risk management, exit ramps, and clear roles and responsibilities is essential.

5

N RC shared its perspective on the benefits and challenges of harvesting in regulatory research.

Harvested materials are valuable due to the representative nature of their aging conditions, which may reduce the uncertainty associated with t he applicability of the results to operating plants compared to tests with alternative aging conditions. Harvested materials may be the best option to address technical data needs identified for extended plant operation. With increasing harvesting opportunities from decommissioning plants, a proactive approach to harvesting planning can optimize benefits by identifying t he right material with the right aging conditions for the identified knowledge gap. There are sign ificant challenges associated with harvesting, including cost, schedule, and logistics, but hopefully these can be mitigated or avoided by leveraging resources with other organizations and learning from past experience.

GRS described its role as the main technical support organization in nuclear safety for the German federal government. GRS provides technical assessment and knowledge transfer for decommissioning activities, aging management, and long-term operation for German federal and interna,tional organizations.

CRIEPI discussed its view of how harvested materials and laboratory prepared materials contribute to addressing technical issues. Harvested materials provide exposure to actual plant cond it ions, but are more limited in availability and the size of the data set that can be generated. Laboratory prepared materials general involve accelerated or simulated aging conditions, but can be used to produce larger data sets and varying parameters can allow understanding of the effect on the mechanism or property of interest. Harvested materials offer fact finding of actual plant conditions as well as confirmation and verification of results from laboratory prepared specimens.

Discussion Summary The discussion following the presentations in this session focused on clearly identifying the need to be addressed by a harvesting project and the myriad cost, schedule, and logistical challenges associated with harvesting. Leveraging with other organizations to defray costs can also help improve the value of a given program, but also adds complexity as another organization may have a different set of priorities that changes the focus of the harvesting effort.

Session 2. Technical Data Needs for Harvesting Session 2 focused on discussing the technical data needs for harvesting and what specific knowledge gaps organizations are interested in addressing through harvesting. This discussion included general perspectives on how to determine when harvesting should be pursued rather than other types of research. As shown in Appendix II with prese111tation t itles, speakers for this session included:

Pradeep Ramuhalli from the Pacific Northwest National Lab (PNNL),

Matthew Hiser from NRC, Keith Leonard from Oak Ridge National Laboratory (ORNL),

Rachid Chaouadi from the Belgian Nuclear Research Centre (SCK-CEN) in Belgium, and Arzu Alpan from Westinghouse.

Presentation Summaries PNNL presented their work, under a small NRC contract, to develop a systematic approach to prioritize data needs for harvesting. PNNL proposed five primary criteria for prioritizing harvesting:

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Unique field aspects of degradation o

For example, unusual operating experience or legacy materials (composition, etc.) that may be no longer available Ease of laboratory replication of degradation scenario (combination of material and environment) o For example, simultaneous thermal and irradiation conditions may be difficult to replicate or mechanism sensitive to dose rate may not be good for accelerated aging Applicability of harvested materials for addressing crit ical gaps o

Prioritize harvesting for critical gaps over less essential data needs Availability of reliable in-service inspection (ISi) techniques for the material/ component o

If inspection methods are mature and easy to apply to monitor and track degradation, perhaps the effort of research with harvested materials is not needed.

Availability of materials for harvest ing o

The necessary materials/ components must be available to be harvested.

PNNL then presented t heir application of these criteria to four materials degradation issues as an example: electrical cables, cast austenitic stainless steel (CASS), reactor vessel internals, and dissimilar metal welds. Based on applying these criteria to t he examples, PNNL concluded that electrical cables, CASS, and reactor internals are all higher priority for harvesting due to unique aspects of the degradation that are challenging to replicate in the lab. Meanwhile, dissimilar metal welds are of low priority due to the ease of replication in lab aging studies as well as the significant body of knowledge and research on the phenomena.

NRC presented a summary of data needs it is interested in pursuing through harvest ing. These included RPV materials to validate fluence and attenuation models and to demonstrate the conservatism of regulatory approaches for transition temperature prediction. Other metal components of interest for harvesting would address data gaps in irradiated stainless steels, as well as improve understanding of inspection capabilities and fatigue life calculations. Electrical components of int erest include low and medium voltage cables and other electrical components for degradation studies, and electrical enclosures and cables for fire research. Concrete components of interest include irradiated concrete, concrete undergoing alkali-aggregate reactions, post-tensioned structures, reinforcing steel, tendons, and spent fuel pool concrete to assess potential boric acid attack.

DOE/ORNL presented their perspective on dat a needs for harvesting and its role in providing validation of experimental and theoretical research. DOE/ORNL performed a significant RPV harvesting program at the Zion nuclear power plant to reduce uncertainties in the Master Curve methodology, validate modeling predictions and study flux and fluence attenuation effects. The harvesting is largely complete, but the testing program is currently underway. DOE/OR NL also indicated interest in usi ng harvested materials to validate its models for swelling and microstructural changes of stainless steel internals under LWR irradiation conditions. Harvesting concrete components would be of interest due to lack of literature data and the multiple dependent variables t hat may affect concrete performance. Finally, DOE/ORNL has been involved in harvesting cables from the Crystal River and Zion plants to address cable aging as a function of material composition and environment.

SCK-CEN presented their interest in an international cooperative program to harvest RPV materials. SCK-CEN presented their survey of the literature for past testing programs of harvested RPV materials, and 7

the limitations of t hese past program. Key limitations include a lack of archive materials, generally lower temperatures, and poor surveillance programs and dosimetry. SCK-CEN then shared some thoughts on their criteria for a new harvesting efforts, including higher fluence levels and temperatures, available archive materials and reliable information on operating history, dosimetry and surveillance program.

Other topics relevant to a new RPV harvesting effort include technical issues such as material variability and irradiation conditions as well as logistical and financial considerations.

The final presentation in Session 2 by Westinghouse focused on the need for harvesting irradiated concrete to better understand the threshold radiation level for sign ificant strength reduction. Westinghouse has installed ex-vessel neutron dosimetry (EVND) at a number of plants in the world and proposed to use these dosimetry measurements to validate fluence model calculations to better understand the uncertainty in these calculations. Figure 1 show s a schematic of the EVND setup. If DoS1metry capsules

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Support bar Dosimetry chain concrete can be harvested at one of these plants Westingt,ouse with EVND data, then irradiated concrete properties from testing can be paired with fluence data to improve research benefits.

Discussion Summary Figure 1 Schematic of Westinghouse ex-vessel neutron dosimetry (EVND)

The discussion following Session 2 presentations touched on a number of topics. EPRI shared that they developed a report related to the topics of Session 2, but more narrowly focused on pressurized water reactor (PWR) internals. MRP-320, "Testing Gap Assessment and Material Identification for PWR Internals," focuses on priorit izing opportunistic harvesting of st ainless steel reactor internals components that may be removed from service following MRP-227 inspections. The methodology and approach in this report may be relevant to the broader harvesting data needs discussion. This report is not p ublicly available, but is available to EPRI member utilities.

Workshop participants discussed the criteria proposed by PNNL in the first presentation. One additional criteria suggested by EPRI was to consider fleet-wide vs. plant-specific applicability. More broadly applicable materials would be of greater interest for harvesting than those that represent conditions at only a few plants. Another criteria suggested is the availability of material pedigree information, such as composition, processing, environmental conditions (temperature, humidity, fluence, etc.). Another suggested criteria was the ease of harvesting, which includes the concept of weighing costs vs. benefits as w ell as project risk. For example, highly irradiated internals are probably much more difficult and expensive to harvest than electrical cables or unirradiated concrete. Further discussion touched on the idea that different organizations may priorit ize t he various criteria different ly, but all will probably at least want to consider t he same set of criteria.

Another key theme from t his discussion was that a successful program should be guided by a clearly defined objective or problem statement to be addressed. This objective should be well-understood at the initiation of a program and used to guide decision-making through implementation of a harvesting 8

project. This also raises a related point or potential criteria: the timeliness of the expected research results relative to the objective. If the results are needed in the next two years, but a harvesting project will not provide results for at least five years, t hat should be a strong consideration.

Session 3. Sources of Materials Session 3 focused on discussing sources of materials for harvesting. This discussion covered previously harvested materials as well as sources for new harvesting programs from operating or decommissioning plants. Both domestic and international sources of materials were discussed in this session. As shown in Appendix II with presentation titles, speakers for this session included:

Matthew Hiser from NRC, Al Ahluwalia from EPRI, Tom Rosseel from DOE/ORNL, John Jackson from DOE/Idaho National Laboratory (INL),

Gerry van Noordennen from EnergySolutions, Arzu Alpan from Westinghouse, Uwe Jendrich from GRS, and Daniel Tello from the Canadian Nuclear Safety Commission (CNSC).

Presentation Summaries NRC presented their perspective on sources o.f materials for harvesting. First, NRC shared informat ion on some of t he harvested materials from past research programs that may be available, including irradiated stainless steel internals, RPV materials, nickel alloy welds, neutron absorber material, a,nd electrical components. NRC then summarized the recently and planned shutdown U.S. plants, including their design, thermal out put, and years of operation, to provide participants with an idea of the potential sources from decommissioning U.S. plants. Finally, NRC shared a list of information that would be helpful to acquire from decommissioning plarnts to determine the value of components for harvesting.

This information included plant design information (component location and dimensions),

environmental conditions (temperature, fluence, humidity, stress, etc.) and operating history, material pedigree information (fabrication records), and inspection records (for interest in components with known flaws).

The next presentation from EPRI covered harvesting opportunities at decommissioning plants in Korea and Sweden. In Korea, Kori-1 is a Westinghouse 2-loop PWR (sister plant is Kewaunee) that will shut down in 2017 after 40 years of operation. Korea Hydro and Nuclear Power Central Research Institute (KHNP-CRI) is planning a comprehensive research program on long-term materials aging based on harvesting from Kori-1 and is seeking international participation in the harvesting effort. KHNP-CRl's plan is focused on metallic components, including RPV, internals, primary syst em components, steam generator materials. Harvesting is expected to occur in 2024 with testing to follow through 2030.

In Sweden, Vattenfall is currently harvesting in 2017-2018 RPV material from t he decommissioning Barseback boiling water reactor (BWR) units. This work is focused on irradiation embrittlement, including comparison of surveillance data to actual RPV properties, as well as thermal aging embrittlement. In the future, Vattenfall will be shutting down Ringhals 1 and 2 in 2020 and 2019, respectively. Ringhals 1 is a BWR and Ringhals 2 is a Westinghouse 3-loop PWR design. Of particular note, Ringhals 2 has the second oldest replaced Alloy 690 RPV head and steam generators. Other 9

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(b )(4) harvesting opportunities at Ringhals include RPV material with a significant surveillance program, thermal aging effects on low alloy steel from the pressurizer, as well as concrete structures. Vattenfall is open to working with partners that are interested in joining them for harvesting at Ringhals.

The next presentation by DOE/ORNL focused on several harvesting programs that DOE's LWRS program has been involved with. DOE/ORNL has led the harvesting of components from the Zion I

......... L(p){4) pl.~ri{]in t he U.S. From Zion, DOE/ORNL has harvested electrical cables and components, a large RPV

............ s~ct ion, and a significant number of records to provide information on material fabrication, in-service inspection and operating history. Cables from Zion include CROM, thermocouple, and low and medium voltage cables. DOE/ORNL indicated some t hermocouple cables from Zion may be available for other t r~e"'s:,:e:a~r..

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-,,,_--.-=-----,,,---,--,----,------'DOE/ORNL is also participating in efforts to harvest cables from Crystal River (led by EPRI) and concrete from the Zorita plant in Spain (led by NRC).

The next presentation by DOE/I NL described I NL's Nuclear Science User Facilities (NSUF) and the Nuclear Fuels and Materials Library (NFML). NSUF is coordinated by INL and facilitates access to nuclear research facilities around t he world, including neutron and ion irradiations, beamlines, hot cell testing, characterization and computing capabilities. NFML is a Web-based searchable database sample library that captures the information from thousands of specimens available to NSUF. NFML is designed to maximize the benefit of previously irradiated materials for future research. Researchers can propose new research projects under NSUF using specimens in NFML using DOE funding.

As seen in Figure 2, the information captured in

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Database Design NFML aligns well with t he goal of t his session to potentially develop a database of previously harvested materials.

The next presentation by EnergySolutions offered a more practical perspective on considering sources of materials for harvesting. From t he plant owner perspective, t here is no financial incentive to support harvesting during decommissioning, therefore researchers need to absorb the costs of harvesting and have a clear scope for harvesting. Flexibility in funding for harvesting activities is essential as the decommissioning process and schedule may change quickly.

EnergySolutions provided valuable perspective on the timing in the decommissioning process for harvesting different components. For instance, t he harvesting of RPV surveillance coupons should take place when the RPV internals are cut and removed. Harvesting of RPV materials is only possible from larger RPVs, as smaller RPVs are shipped intact to t he disposal facility, rather than cut into pieces. Spent fuel rack neutron absorber coupons must be harvested either before or after the dry storage campaign to remove spent fuel from the spent fuel pool. Harvesting actual spent fuel rack neutron absorber 10

material must come after the pool is completely empty. Electrical cables and other components from mild environments may be harvested at any time (once temporary power is established and plant power is shut off), while the harvesting of electrical components from high radiation environments will depend on the timing of source-term removal schedules. Concrete cores are best harvested when other cores are being taken for site characterization to develop the License Termination Plan. Highly irradiated concrete from the biological shield wall would need to come later in decommissioning after the RPV is removed.

In terms of upcoming decommissioning plants, EnergySolutions indicated that San Onofre and Vermont Yankee will be entering active decommissioning in 2018 and 2019, respectively. Kewaunee, Crystal River, and Fort Calhoun also may enter active decommissioning in the next 2 years. If researchers are interested in harvesting from any of these plants, they should be reaching out to plant owners immediately to begin planning and coordination, Westinghouse followed up their presentation in Session 2 by describing an opportunity to harvest concrete from the Mihama 1 plant in Japan. Westinghouse installed and analyzed additional neutron dosimetry in the reactor cavity for one cycle, which were used to validate the radiation transport calculations. Mihama was shutdown in 2015 and is in contact with Westinghouse about the possibility of extracting concrete cores from the biological shield wall. Westinghouse is seeking partners interested in joining this harvesting effort.

The next presentation by GRS covered opportunities for harvesting from German plants. Regulations in Germany require plants to either immediately dismantle or dismantle after a period of safe enclosure, which is largely consistent with options in the U.S. GRS detailed the status of German commercial reactors, which are predominantly BWR and PWR designs. Seventeen reactors are currently undergoing decommissioning, while seven more are currently shutdown and await a decommissioning license. Eight reactors are still operating with scheduled shutdown dates between 2017 and 2022. German RPVs tend to have lower fluence than U.S. designs due to a larger water gap in the downcomer region. Germany has limited experience wit h harvesting from decommissioning plants. One question that GRS will follow-up on is the "rumored" cable surveillance programs that may be used in Germany and could provide experience and lessons learned for other countries.

The final presentation in Session 3 was by CNSC on harvesting opportunities in Canada. Atomic Energy Canada Limited (AECL) has harvested seven concrete cores from the 20 megawatt electric (MWe)

Nuclear Power Demonstration Plant (NPD), which shutdown in 1988 after 25 years of operation. CNSC and AECL are also considering opportunities to harvest concrete from other decommissioned reactors in Canada such as Gentilly-2, Douglas Point, and Whiteshell Reactor 1. In addition to concrete, CNSC and AECI. are currently harvesting electrical cables from the 675 MWe CANDU-6 Gentilly-2 reactor, which shutdown in 2012 after 29 years of operation. The purpose of this work is to study cable degradation from t hermal aging and radiation damage and validate environment al qualification of the cables. CNSC described some of the challenges with this harvesting effort, such as working with plant owners, records, accessibility and contamination of the materials and budgeting with unexpected delays in harvesting.

A future harvesting opportunity is from the National Research Universal (NRU) reactor at Chalk River, which will shut down in 2018 after operating since 1957. AECL is currently taking an inventory of irradiated materials that can be harvested from NRU In decommissioning. Potential materials for 11

harvesting include metals (steels, nickel alloys, zirconium, aluminum), concret e, graphite, active equipment (pumps, etc.), graphite seals, electrical cables, and thermocouples.

Discussion Summary Following the presentations, there was some discussion of lessons learned from DO E's Zion harvesting effort. DOE worked with a former senior reactor operator at Zion to identify and acquire the appropriate records from Zion for t he components being harvested. DOE also described their flexible approach to acquiring RPV samples by sending a large chun k of mat erial (weighing ~go tons) to EnergySolut ions' facility in Tennessee, where smaller pieces (weighing ~soo pounds) were cut to send to ORNL. Most of the decontamination was performed at Zion, wit h minimal additional cleaning (as well as cladding removal) taking place at EnergySolut ions' facility.

There was also discussion of acquiring materials from sources other than commercial nuclear facilities.

DOE has considered harvesting concrete from other DOE nuclear facilities, but determined that there were compositional differences between the DOE facilities and commercial facilit ies that would make the concrete from DOE facilit ies not useful. DOE/I NL mentioned that the Advanced Test Reactor (ATR) replaces their core internals every ten years. The ATR internals are composed primarily of 347 stainless stee l and achieve very high fluence levels after ten years of service.

Another key discussion topic was the possibility of developing a database for previously harvested materials or those available for future harvesting. DOE/I NL Indicated that their NSUF sample library may be a good starting point for such a database, although any materials in t hat library should be freely available for use in the research community. CNSC, NRC, and PNNL also expressed interested in working to develop a harvesting database.

Session 4. Harvesting Experience: Lessons Learned and Practical Aspects Session 4 focused on lessons learned and practical aspects of harvesting. Presenters shared t heir experience with past harvesting programs, particularly common pitfalls to avoid and successful st rat egies to overcome them. Present ations also covered the practical aspects of harvesting from the plant owner and decommissioning company perspective. As shown in Appendix II wit h presentation titles, speakers for this session included:

Jean Smith from EPRI, Tom Rosseel from DOE/ORNL, Matthew Hiser from NRC, Taku Arai from CRIEPI, Gerry van Noordennen from EnergySolutions, and Bill Zipp from Dominion.

12

Presentation Summaries EPRI presented their experience and lessons learned from past harvesting programs, particularly harvesting reactor internals and concrete from Zorita and electrical cables from Crystal River. From the Zorita reactor internals experience, EPRI emphasized that

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encounter both material retrieval and on-site challenges, and shipping Issues. As Figure 3 Zorita Internals Research Project (ZIRP) Timeline shown in Figure 3, the Zorita Internals Research Project (ZIRP) took about 10 years to go from initial planning to final results, which included about 5 years of project planning, 2 years for material extraction (on-site logistics and shipping), and 3-4 years for testing. EPRl's experience was that decommissioning activities were the top priority and that harvesting was secondary, subject to schedule and logistical challenges based on the changing decommissioning schedule. Shipping issues were also challenging due to sending activated materials (which were classified as "waste") acros.s international borders, from the reactor in Spain to the testing facility in Sweden. Currently, further planned shipments of the Zorita materials beyond the initial program continue to be impacted by export license challenges in Sw eden. More positively, EPRI emphasized that the Zorita reactor internals materials harvesting showed excellent cooperation among many organizations and are now providing valuable technical information to numerous research projects.

Lessons learned from the Zorita concrete harvesting focused on the challenges with core sample drilling and handling contaminated concrete. Ultimat ely, an effective core drilling procedure was identified, but required some trial and error. Lessons learned from t he Crystal River cable harvesting included material concerns, t he need for on-site support, and cost. In terms of material concerns, radiation and asbestos contamination created additional challenges for harvesting. On-site support and the ability to visit the site are extremely valuable to ensure clear communication, retrieval or records for material pedigree information, and awareness of on-site developments in the decommissioning process. Cable harvesting at Crystal River was more expensive than anticipated, particularly in terms of EPRI project management time to coordinate the harvesting activities and engineering support at the plant.

DOE/ORNL presented lessons learned primarily from the experience harvesting RPV materials and electrical cables and components from the Zion plant. In terms of planning and decision-making, DOE/ORNL had several lessons learned. DOE/ORNL hosted a workshop at Zion in 2011 to discuss long-term goals and objectives, which proved very helpful in setting priorities and developing partnerships with other organizations. Partnerships were very valuable to DOE/ORNL's harvesting efforts, allowing for leveraging resources and collaboration and sharing results. There are limited opportunities for harvesting key components, so DOE/ORNL emphasized that participants should take full advantage of the opportunities that arise, understanding that t here is a necessary compromise between the materials available and their value in terms of fluence or exposure to aging conditions. Another consideration is the quant ity of material harvested, which should be sufficient for the objectives of the planned research as well as any collaborations or partnerships, but limited to control costs.

For implementing the harvesting program, DOE/ORNL found that flexibility was paramount to be able to adjust scope and plans in response to schedule changes and other developments, while remaining within cost constraints. Working with a former reactor operator was extremely valuable to benefit from 13

their in-depth knowledge of all parts of the plant, in particular the records for materials pedigree information. Regular site visits and contacts were also essential to stay aware of t he latest developments in the harvesting planning and decommissioning process, with the understanding that harvesting is not the top priority for the decommissioning company, Other important considerations were hazardous materials handling, transportation, and disposal and logistics, including contracts, liability, shipping and disposal. Finally, DOE/ORNL's experience is that the total costs ofa harvesting program from planning to execution to testing are very high, so t hey should be carefully weighed against the value of the expected data to be generated.

NRC presented their experience, including benefits from previous harvesting programs, and t echnical and logistical lessons learned from harvesting. As an organization, NRC has extensive experience with testing harvested materials, including RPV, primary system components, reactor internals, neut ron absorbers, concrete and electrical components. NRC's experience is more limited than DOE or EPRI in terms of managing the logistics of a harvesting effort from a decommissioning plant. NRC has generally participated in a secondary role in cooperative efforts or received failed components from operating plants for research, NRC has found that previous harvest ing efforts have been effective in reducing unnecessary conservatism, understanding in-service flaws more realistically for NOE and leak rat e methodologies, as well as identifying and better understanding safety issues.

For t echnical lessons learned, NRC's perspective is t hat harvesting can provide highly representative aged materials for research, which may be the only practical source of such materials. Harvested materials can be effectively used to validate models or a larger data set from accelerated aging tests. It is important to understand as much as possible about the materials and their in-service environment and how this compares with the operating fleet of reactors before committing to a specific harvesting project. For logistical lessons learned, harvesting is expensive and time-consuming, so a significant technical benefit is needed to ensure the program provides value. Leveraging resources with other organizations can help minimize costs, but can also introduce challenges for aligning priorities and interests of mult iple organizations. Finally, t ransporting irradiated materials, particularly between countries, is challenging and t ime-consuming and should be avoided if at all possible.

CRIEPI presented t heir research experience with harvested materials as well as ongoing harvesting from the Hamaoka 1 plant. The first research program involved atom probe tomography (APT) on RPV surveillance materials. CRIEPI found a correlation between t he volume fraction of Ni-Si-Mn clusters and the change in nil-ductility temperature. In the second research project, CRIEPI characterized the weld and base materials harvested from Greifswald Unit 4 RPV with small-angle neutron scatt ering, APT, and hardness testing. In t he third research project, CRIEPI performed APT on 304L stainless steel reactor internals harvested from control rod and top guide components from 3-13 dpa. Results showed a strong increase in Ni-Si clusters with increasing fluence, but little variation in Al enriched clusters with increasing fluence.

For future work, CRIEPI is collaborating with t he DOE LWRS program to invest igate RPV materials (b)(4)

~~.'.".'.:~:.'.:~,f,~?~ ~i*()*~.l

!CRIEPI also presented activities underway by Chubu Electric Power to harvest RPV and concrete samples from t he Hamaoka 1 plant.

Hamaoka 1 is a 540 MWe BWR-4 that operated for 33 years. Harvesting began in 2015 and will cont inue through 2018.

14 Commented [Fl2]: Was this a VVER-440 in the former GDR?

Yes

The final two presentations of Session 4 provided the non-researcher's perspective from a decommissioning company and plant owner. EnergySolutions, which Is decommissioning the Zion nuclear plant among other facilities, presented on the decommissioning process and t heir experience and lessons learned from harvesting at Zion. As mentioned previously, surgical harvesting Is not the top priority for decommissioning, so researchers must recognize this and coordinate closely with the decommissioning company. EnergySolutions emphasized the need to gain senior management support at the plant as well as to expect that there may be staff turnover during a multi-year harvesting effort.

Changes in scope and schedule (originating from either side) can cause frustration on booth sides. Early planning, efficient contracting, and frequent site visits are important to avoid lost opportunities and achieve a successful outcome.

At Zion, EnergySolutions worked with DOE to harvest RPV materials, cables, electrical components, and spent fuel storage racks. DOE hoped to harvest a particular RPV surveillance capsule, but was unable to do so due to the inability to identify the correct capsule. There were also challenges with harvesting RPV materials. The cut line on the Unit 2 RPV was too close to the weld to be used for research; fortunately, a successful specimen was harvested from Unit 1. For cabling, the init ial plan was to harvest from 11 different locations, but ultimately, due to unforeseen challenges and poor communicat ion and coordination, only 4 different cable locations were harvested. Harvesting the desired cable length (30 feet) also proved challenging, with only shorter sections recovered. Searches of plant records were largely effective at providing material pedigree informat ion for cables. Concrete coring was init ially planned t o take place at Zion, but not performed due to lack of research interest. The spent fuel storage rack harvesting went smoothly, which was assisted by weekend efforts when decommissioning activities were not occurring.

The next presentation from Dominion provided its perspective on harvesting from decommissioning plants, focused on the experience at Kewaunee Power Station. The top priority (beyond safety) in decommissioning is t he preservation and good stewardship of the decommissioning trust fund. Staffing is the largest drain on the trust fund, so at Kewaunee, staff was halved within a few months of shutdown and then halved again, about 16 months after permanent shutdown once offsite emergency response requirements were eliminated. Dominion described the example of harvesting the RPV surveillance capsules at this point at Kewaunee and the significant challenges that would exist. Given the reduced staffing and the current plant state (reactor coolant system drained, pumps retired, crane and radiation monitoring not maintained), it would be much more difficult than immediately after shutdown.

Kewaunee considered harvesting the RPV surveillance specimens and estimated a cost of six to seven figures based on all the activities required to enable it at this point, post-shutdown, compared to a much lower cost just after shutdown. Dominion observed that some components, such as cables or electrical components, may be available and relatively easy to harvest at almost any time during decommissioning. However, other components such as highly irradiated internals or RPV may be best harvested either shortly after shutdown when staffing and capabilities on-site are high or wait until active demolition of the reactor, which may be years or decades later.

Dominion also touched on the discussion of records for plant components. Records requirements are limited to those needed for safety. Once the plant shuts down and the range of potential safety concerns decreases, systems are downgradecl to non-safety and the associated records are no longer required to be maintained. For perspective, Kewaunee still has all its records four years since shutdown, but w ill likely not continue this much longer. Dominion closed its presentation with a broader 15

perspective on harvesting, emphasizing the need to clearly define a problem statement and understand what technical and regulatory purpose this harvesting will serve. Early planning focused on achieving the clear objective of the work including scope, schedule, budget and contact with plant is essential to a successful harvesting effort.

Discussion Summary The discussion touched on the top lessons learned from past harvesting efforts, which included defining a clear objective and purpose for harvesting, early engagement with the plant, and site coordination during harvesting.

Another suggestion was to get utility management buy-in for the harvesting project by identifying a benefit to the utility. EPRI mentioned that cable harvesting at Crystal River went much more successfully once the utility recognized the potential benefits for SLR. Similarly, when harvesting from an operating plant, one must recognize and work through the challenges the plant may encounter when restarting operations.

During discussion, the question was raised regarding how it is determined whether harvested materials are waste. The discussion concluded that in the U.S. 10 Code of Federal Regulations (CFR) 37 is the important consideration. 10 CFR 37 defines when additional security requirements are imposed, based on the quantity and activity of materials to be transported. The definition of material as waste versus research materials is not as critical in t he U.S. EnergySolutions indicated that their shipments of waste or research material could be handled in the same way in the accordance with Department of Transportation regulations, provided that the limits in 10 CFR 37 were not reached.

Session S. Future Harvesting Program Plan nlng Session 5 focused on the information needed for informed harvesting decision-making and harvesting program planning. This session featured a presentation by Pradeep Ramuhalli from PNINL, followed by a discussion period covering harvesting program planning and reflection on the 2-day workshop.

Presentation Summary PNNL presented its perspective on t he information needed for informed harvesting decision-making.

First, the purpose of the harvesting effort needs to be defined by identifying the technical knowledge gaps to be addressed. Next, a research plan should be developed demonstrating how the harvested material will be used to address the identified gaps. Finally, the appropriate source of material to address the technical gap must be identified, along with resources to support the effort and plans and timelines to perform the harvesting. The specifics of these plans depend greatly on the source of materials and must be flexible based on changing conditions on the ground.

In assessing the best source of materials, researchers should consider the material, its environment, and its condition. Material information includes fabrication information such as manufacturer, composition, and dimensions as well as information related to installation or construction, such as welding processes and parameters. Environmental information includes temperature, humidity, fluence, flux, stress (service, residual, installation), and coolant chemistry. Component condition information includes inspection history, such as identified flaws or degradation.

16

Discussion Summary The discussion in Session 5 focused on t he best practical approach to plan future harvesting programs.

There was clear agreement that this approach must begin with ident ifying t he data needs best addressed by harvesting, whether from operating or decommissioning plants. Once a specific need Is identified, the next step is to find a source to acquire the materials of interest as well as other organizations interested in participating in the harvesting effort.

Key Takeaways from Workshop Session 1. Motivation for Harvesting The clear takeaway from the discussion in Session 1 was that harvesting requires significant resources to be done successfully; therefore it is paramount to identify how the planned harvesting will clearly address a significant need to ensure the harvesting project provides strong value. In t he context of the need for data, EPRI suggested t hat the goal of harvesting to support research for operation out to 80 years should not be a comprehensive understanding of all aspects of degradation, but rather a snapshot to confirm other lab results and models. This is an important point for all organizations and researchers to keep in mind before investing significant resources in harvesting.

Session 2. Technical Data Needs for Harvesting The criteria proposed by PNNL are a good starting point for prioritizing issues to address by harvesting.

Three additional important criteria would be:

Fleet-wide vs. plant-specific applicability of data, Ease of harvesting (in terms of cost and project risk), and Timeliness of the expected research results relative to the objective.

Once a potential harvesting project has reached the point of looking at different sources of materials, the availability of material pedigree information, such as composition, processing, environmental conditions (temperature, humidity, fluence, etc.) is very important to the overall value of harvesting from that particular plant.

Based on the presentations and discussion in Session 2, there appeared to be two areas where participants had broad interest in pursuing further harvesting: high fluence reactor internals and irradiated concrete. The common drivers for the interest in these issues is a lack of representative data at the fluences of interest and significant challenges with acquiring representative data, through other means. High fluence reactor internals have been addressed somewhat by ZIRP, but st ainless steel materials exposed to higher fluence levels at h igher temperatures, where void swelling may become sign ificant, could help validate DOE and EPRI models and provide further technical basis for PWR internals aging management. Irradiated concrete harvesting is currently being pursued from the Zorita reactor in Spain, with international collaboration and potential testing at the Halden Reactor Project.

Other areas with some, but less widespread, interest expressed from workshop participants for new harvesting efforts included RPV materials and electrical cables and components. SCK-CEN and NRC expressed interest in RPV harvesting, and NRC expressed interest in electrical component harvesting.

17

Session 3. Sources of Materials To capture the key takeaways from Session 3 focused on sources of materials, two tables of potential sources of materials are presented below. Table 1 covers recent or ongoing harvesting programs, while Table 2 details potential future harvesting opportunities.

Table 1 Ongoing Harvesting Proitrams Country Plant Design Size Years in Components Organization(s)

(MWe) operation Canada NPD CANDU 20 25 Concrete Gentilly-2 CANDU-6 675 29 Cables AECL Japan Hamaoka 1 BWR-4 540 33 RPV, concrete CRIEPI, Chubu Spain Zorita w 1-loop 160 37 Internals, concrete EPRI, NRC Sweden Barseback ABB-II 6,15 28 RPV Vattenfall Zion1/2 W - 4 1040 24/25 RPV, cables, DOE, EPRI, NRC loop neutron absorbers U.S.

Crystal River 3 B&W 860 36 Cables EPRI (b )(4)

Table 2 Potential Future Sources for Harvesting Country Plant Design Size Years in Potential Notes (MWe) operation Components Canada NRU Test reactor 135 61 TBD AECL; SD:

MWt 2018 Germany Numerous plants either in decommissioning or shutting down soon. See Appendix Ill.

Japan M ihama W 2-loop 320 40 Concrete

Kansai, Westinghouse RPV, internals, Korea Kori 1 W 2-loop 576 40 SGs, pressurizer, KHNP, EPRI welds, CASS, Ringhals 1 BWR 883 44 RPV, internals Vattenfall; Sweden Ringhals 2 W 3-loop 900 44 SGs, pressurizer, SD: 2020 /

concrete 2019 Kewaunee W 2-loop 566 39 TBD SD: 2013 SONGS 2/3 CE 2-looo 1070 31/30 TBD SD: 2013 Crystal River 3 B&W 860 36 TBD SD: 2013 Vermont BWR-4/Mk-1 605 42 TBD SD: 2015 U.S.

Yankee Fort Calhoun CE 2-loop 482 43 TBD SD: 2016 Palisades CE 2-loop 805 47 TBD SD: 2018 Pilgrim BWR-3/Mk-1 677 47 TBD SD: 2019 Oyster Creek BWR-2/Mk-1 619 so TBD SD: 2019 18

Indian Point w 4-loop 1020 /

48/46 TBD SD: 2021 2/3 1040 Diablo Canyon W4-loop 1138/

40 TBD SD: 2024-5 1/2 1118 Non-Advanced 250 commercial; Test Reactor Test reactor MWt so Core internals internals replaced every 10 years In addition to the potential sources of materials presented and discussed in Session 3, another takeaway was the suggestion of developing a database for previously harvested materials or those available for future harvesting. The NSUF sample library may be a good starting point for such a database, with appropriate modifications for the purposes of harvesting efforts.

Session 4. Harvesting Experience: Lessons Learned and Practical Aspects There were several important takeaways from Session 4 that were touched on in multiple presentations and the following discussions. One key takeaway is that researchers should identify a clear purpose and scope for harvest ing. Having a clear purpose for harvesting helps to guide later decisions that must be made to adjust course when t he inevitable changes in schedule or unexpected realit ies at the plant arise. A related note is that harvesting is not the top priority for decommissioning. Therefore, researchers must have clear objectives and scope for harvesting that can be communicated to the site.

This understanding should shape assumptions and interactions with the plant owner or decommissioning company as well as planning for costs and schedule.

Another takeaway was the value of strong site coordination, including site visits. Multiple presenters touched on the value of being on-site to talk to staff and see the components to be harvested. Mockups and 3-0 simulations can be valuable to ensure success of the approach or technique used to acquire the specimen. A related point is working with reactor operators at the plant. Several harvesting efforts worked with former reactor operators and benefited greatly from their experience to fi nd records or determine the best method to harvest the desired component. This is a valuable insight that could be effective in future harvesting efforts.

A third key takeaway is early engagement with the plant personnel to express interest in harvesting. This serves to make the plant aware of interest in harvesting and get their support to work w ith the harvesting process. The other important benefit of early engagement is to gain as much information as possible about the available materials and components, including the associated records and material pedigree information.

Session 5. Future Harvesting Program Planning The key takeaway in Session 5 was to gather as much information as possible in advance of committ ing to a specific harvesting project. Ideally, there would be a strong understanding that the material and its aging conditions clearly align with an identified t echnical data need before committing significant resources to a harvesting effort.

Action Items and Next Steps The following is a summary of the action items discussed at t he end of the workshop:

19

l. Sharing r,vorkshop slide~

NRC emailed attendees to ask their comfort with sharing their workshop slides with ot her organizations and received no objection from any presenters.

The presentations can be accessed here:

httos://drive.google,com/open ?id=0BS DWMLchSYSXcnoZZ0JOS0SSQU u '

2, EPRI indicated t hat MRP-320 (Product ID: 1022866) on knowledge gaps for irradiated austenitic stainless steel for potential harvest ing from MRP-227 inspections is publicly available for a fee.

3. Cable surveillance programs in Germany GRS to inquire with cable colleagues and share any insights.

4. Sources of materials database Potential sources of materials presented in this workshop are summarized in Session 3 summary above and Appendix Ill below.

NRC will be reaching out to PNNL, INL NSUF, CNSC, AECL, and any other organizations interested in dat abase development,

5. Priorit ized data needs Suggest ion to continue discussions on prioritized data needs within technical areas (RPV, internals, electrical, concrete) through exist ing coordination groups if possible Focus on identifying specific material/ aging conditions of interest and purpose

/ intended outcome of harvesting Idea to survey participants at the Environmental Degradation conference John Jackson (INL) is o n planning committee

6. EPRI report on spent fuel liner boric add transport through concrete NRC will contact EPRI for report if needed.

7. Harvested Materials Research Results Section of workshop summary report (below) devoted to references from harvested materials research.

References to Previous Harvested Materials Research This section of the workshop summary addresses a question t hat was raised during t he discussion at the workshop regarding what t he outcome or benefit of past harvesting efforts have been. Below is a list of references to research results generated from test ing of harvested materials:

1. J,R. Hawthorne and A.L. Hiser, Experimental Assessments of Gundremmingen RPVArchive Material for Fluence Rate Effects Studies, NUREG/CR-5201 (MEA-2286), U.S. Nuclear Regulatory Commission, October 1988,

2. O.K. Chopra, and W.J. Shack, Mechanical Properties of Thermally Aged Cast Stainless Steels from Shippingport Reactor Components, NUREG/CR-6275 (ANL-94/37), U.S. Nuclear Regulatory Commission, April 1995.

20 Commented [Fl3]: As commented above, should the slides be Included In this report under new appendix?

I will leave out for now and see if there is broader interest. If we do 2 slides per page, that would a > 100 page appendix, which is not ideal to me.

3. G. J. Schuster, S. R. Doctor, S.L. Crawford, and A. F. Pardini, Characterization of Flaws in U.S. Reactor Pressure Vessels: Density and Distribution of Flaw Indications in the Shoreham Vessel, NUREG/CR-6471 Volume 3, U.S. Nuclear Regulatory Commission, November 1999.

4. G. J. Schuster, S. R. Doctor, A.F. Pardini, and S.L. Crawford, Characterization of Flaws in U.S. Reactor Pressure Vessels: Validation of Flaw Density and Distribution in the Weld Metal of the PVRUF Vessel, NUREG/CR-6471 Volume 2, U.S. Nuclear Regulatory Commission, August 2000.

5. D.E. McCabe, et al. Evaluation of WF-70 Weld Metal Fram the Midland Unit 1 Reactor Vessel, NUREG/CR-5736 (ORNL/TM-13748), U.S. Nuclear Regulatory Commission, November 2000.

6. B. Alexandreanu, O.K. Chopra, and W.J. Shack, Crack Growth Rates in a PWR Environment of Nickel Allays from the Davis-Besse and V.C. Summer Power Plants, NUREG/CR-6921 (ANL-05/55), U.S. Nuclear Regulatory Commission, November 2006.

7. S.E. Cumblidge, et al. Nondestructive and Destructive Examination Studies on Removed-from-Service Control Rad Drive Mechanism Penetrations, N UREG/CR-6996, U.S. Nuclear Regulatory Commission, July 2009.

8. S. E. Cumblidge, et al. Evaluation of Ultrasonic Time-of-Flight Diffraction Data far Selected Control Rad Drive Nozzles from Davis Besse Nuclear Power Plant, PNNL-19362, Pacific Northwest National Laboratory, April 2011.

9. S. L. Crawford, et al. Ultrasonic Phased Array Assessment of the Interference Fit and Leak Poth of the North Anna Unit 2 Control Rad Drive Mechanism Nozzle 63 with Destructive Validation, NUREG/CR-7142 (PNNL-21547), U.S. Nuclear Regulatory Commission, August 2012.

21

Appendix I Workshop Participants Name Or11anization Email Taku Arai CRIEPI a rait@crieoi.denken.or.io Sadao Higuchi CRIEPI higuchi@criei:1i.denken.or.j [1 Japan Kazunobu Sakamoto JNRA kazunobu sakamoto@nsr.go,i11 Yasuhiro Chimi JAEA chimi,\\/asuhiro@jaea.go.j[!

Uwe Jendrich GRS Uwe.Jendrichors.de Europe Rachid Chaouadi SCK-CEN rachid.chaouadi@sckcen.be Guy Roussel Bel V gU\\/.rDUSSel@Belv.be Daniel Tello CNSC daniel.tellocanada.ca Canada Desire Ndomba CNSC desire.ndomba@canada.ca Karen Huynh AECL khu','nh@aecl.ca Gerrv van Noordennen Enen;iv Solutions QovannoordennenenerQvsolutions.com us Bill Zipp Dominion william.f.zii:1i:1@dom.com Industry Mark Richter NEI mar@nei.org Arzu Alpan Westinghouse al11anfa@westinghouse.com Sherrv Bernhoft EPRI sbernhoft@eori.com Robin Dyle EPRI rd\\/le@e11ri.com EPRI Jean Smith EPRI jmsmith@ei:1ri.com Al Ahluwalia EPRI kahluwal@ei:1ri.com Tom Rosseel ORNL rosseeltm@ornl.2ov Rich Reister DOE Richard.Reister@nuclear.energ.,,.gov Keith Leonard ORNL leonardk@ornl.gov DOE Mikhail A. Sokolov ORNL sokolovm@ornl.gov John Wagner INL john.wagner@inl.gov John Jackson INL john.jackson@inl.gov Pradeep Ramuhalli PNNL Pradeei:1.Ramuhalli@11nnl.gov Pat Purtscher NRC Patrick. Pu rt sch e r@n re. l!OV Rob Tregoning NRC Robert.Tregoning@nrc.gov Matt Hiser NRC Matthew.Hiser@nrc.gov Mita Sircar NRC Madhumita.Sircar@nrc.gov Tom Koshy NRC Thomas.Kosh'{@nrc.gov NRC Jeff Poehler NRC Jeffre'{.Poehler@nrc.gov Allen Hiser NRC Allen.Hiser@nrc.gov Angela Buford NRC Angela.Buford@nrc.gov Mark Kirk NRC Mark.Kirk@nrc.gov Amy Hull NRC Am'{.Hull@nrc.gov Pete Ricardella NRC/ACRS Priccardella@Structint.com 22

Appendix II Workshop Agenda Tuesday, March 7 Session Time Oreanization Soeaker Presentation Title Intro 8:00 NRC Michael Weber Welcome and Introduction to Workshop Robert Tregoning DOE Rich Reister DOE Perspectives on Material Harvestinl!

EPRI Sherry Bernhoft EPRI Perspective on Harvesting Projects 8:15-8:45 NRC Robert Tregoning NRC Perspective on Motivation for Harvesting 1

GRS Uwe Jendrich Role of GRS in Decommissioning and LTO CRIEPI Taku Arai CRIEPI Motivations for Harvested Material 8:45-9:45 DISCUSSION 9:45-10:00 BREAK 10:00-PNNL (for NRC)

Pradeep Ramuhalli Data Needs Best Addressed By Harvesting 10:20 10:20-NRC Matthew Hiser High-Priority Data Needs for Harvesting 10:30 10:30-DOE Keith Leonard LWRS Program Perspective on the Technical 10:55 Needs for Harvestine 2

10:55 -

Review of past RPV sampling test programs 11:20 SCK-CEN Rach id Chaouadi and perspective for long term operation 11:20-Westinghouse Arzu Alpan Importance of Harvesting to Evaluate 11:45 Radiation Effects on Concrete Prooerties 11:45 -

DISCUSSION 12:30 12:30- 2:00 LUNCH 2:00 - 2:10 NRC Matthew Hiser Sources of Materials: Past NRC Harvest ing and U.S. Decommissioning Plants 2:10-2:35 EPRI Ai Ahluwalia Harvesting Plans for Materials Aging Degradation Research in Korea and Sweden 2:35-2:50 DOE/ORNL Tom Rosseel Materials Harvested bv the LWRS Program 2:50-3:00 DOE/INL John Jackson NSUF Material Sample Library 3:00-3:15 Energy Solutions Gerry van Zion Material Harvesting Program Noordennen 3

Potential Harvesting of Concrete from M ihama 3:15 - 3:30 Westinghouse Arzu Alpan Unit 1 3:30- 3:45 BREAK 3:45-4:00 GRS Uwe Jendrich Plants in Decommissioning in Germany Evaluating Structures, Systems & Components 4:00 - 4:15 CNSC Daniel Tello from Decommissioned/Decommissioning Nuclear Facilities in Canada 4:15-5:00 DISCUSSION 23

Wednesday, March 8 Session Time Or2anization S0eaker Presentation Title 8:00-8:30 EPRI Jean Smith Lessons Learned: Harvesting and Shipping of Zorita Materials 8:30- 9:00 DOE Tom Rosseel LWRS Program: Harvesting Lessons Learned 9:00 - 9:30 NRC Matthew Hiser NRC Perspective on Harvesting Experience and Lessons Learned 9:30 - 10:00 CRIEPI Taku Arai CRIEPI Research Activities with Harvested 4

Materials 10:00-10:15 BREAK 10:15 - 10:45 Energy Gerry van Zion Harvesting Experience and Lessons Solutions Noordennen Learned 10:45 - 11: 15 Dominion Sill Zipp Kewaunee Insights on Material Harvesting 11:15 -12:00 DISCUSSION 12:00-1:30 LUNCH 1:30-1:45 PNNL (for Pradeep Ramuhalli Technical Information Needed for Informed NRC)

Harvesting Decisions 1:45 - 2:30 DISCUSSION s

2:30 - 3:00 Action Items and Next Steps EPRI Sherry Bernhoft 3:00- 4:00 DOE Rich Reister Closing Thoughts NRC RobertTregoning ALL 24

Appendix Ill Harvesting Opportunities in Germany Past and current decommissioning projects of P ototype or Commercial Reactors Name I Abbrev.

Rheinsberg KKR Compact Natrium Cooled KKN Reactor Multipurpose Research R.

MZFR Obrigheim KWO Neckarwestheim 1 GKN-1 lsar-1 KKl-1 Gundremmingen-A KRB-A Greifswald 1-5 KGR 1-5 Lingen KWL WWER SNR PWR/O20 PWR PWR BWR BWR WWER BWR Power I Oecom.

MW.

started 70 1995 21 1993 57 1987 357 2008 840 2017 912 2017 250 1983 440 1995 268 1985 UC: unconditional clearance UC UC UC UC UC UC RCAKRB-11 UC UC after SE RCA: radiation controlled area, new license NRC Harvesting Workshop, RoclMHe, March 2017. Oecormisslonlng in Germany SE: safe enclosure Past and current decommissioning projects of Prototype or Commercial Reactors Name Strategy Stade KKS PWR 672 2005 UC Research Reactor J0lich AVR HTR 15 1994 UC Thorium High-THTR-HTR 308 1993 SE since 1997 Temperature-Reaktor 300 W0rgassen KWW BWR 670 1997 UC M0lheim-Karlich KMK PWR 1302 2004 UC Hot-Steam Reactor HOR HOR 25 1983 UC since 1998 Grosswelzheim N iederaichbach KKN IDRRIOp 106 1975 UC since 1994 Test-Reactor Kahl VAK BWR 16 1988 UC since 2010 25

Shut down Commercial Re ctors

• that have no decommissioning license granted yet Name Abbrev.

Reactor type Philippsburg-1 KKP-1 BWR Grafenrheinfeld KKG PWR Biblis-A KWB-A PWR Biblis-8 KWB-8 PWR Unterweser KKU BWR Brunsbuttel KKB BWR Krummel KKK BWR

• Commercial Reactors in operation Name Abbrev.

Reactor type Gundremmingen-8 KRB-11-8 BWR Philippsburg-2 KKP-2 PWR Gundremmingen-C KRB-11-C BWR Grohnde KWG PWR Brokclorf KBR PWR Emsland KKE PWR lsar-2 KKl-2 PWR Neckarwestheim-2 GKN-2 PWR 26 frMiihNM 926 1345 1225 1300 1410 806 1402 Date of application 2013 / 2014 2014 2012 2012 2012 / 2013 2012 / 2014 2015 Anticipated date of final shutdown 1344 31.12.2017 1468 31.12.2019 1344 31.12.2021 1430 31.12.2021 1480 31.12.2021 1406 31.12.2022 1485 31.12.2022 1400 31.12.2022

From:

Sent:

To:

Subject:

Purtscher, Patrick Fri, 19 May 2017 15:57:20 -0400 Hiser, Matthew RE: Workshop Summary Report Note to requester: The attachment is immediately following this email.

Attachments:

Harvesting Workshop Summary Report draft 5-16-17 PTP comments.docx My most significant issue was with the Key takeaway section. I think it would be better t o move much of it to the original discussion of each session.

Pat From: Hiser, Matthew Sent: Tuesday, May 16, 2017 10:43 AM To: Purtscher, Patrick <Patrick.lPurtscher@nrc.gov>; Tregoning, Robert <Robert.Tregoning@nrc.gov>;

Ramuhalli, Pradeep (Pradeep.Ramuhalli@pnnl.gov) <Pradeep.Ramuhalli@pnnl.gov>

Subject:

RE: Workshop Summary Report Sending the latest version with a few references to past research on harvested materials...

Matthew Hiser Materials Engineer US Nuclear Regulatory Commission I Office of Nuclear Regulatory Research Division of Engineering I Corrosion and Metallurgy Branch Phone: 301-4/5-2454 I Office: TWFN I0D62 Matthew.Hiser@nrc.gov From: Hiser, Matthew Sent: Friday, May 12, 2017 5:24 PM To: Purtscher, Patrick <Patrick.Purtscher@nrc.gov>; Tregoning, Robert <Robert.Tregoning@nrc.gov>;

Ramuhalli, Pradeep (Pradeep.Ramuhalli@pnnl.gov) <Pradeep.Ramuhalli@pnnl.gov>

Subject:

Workshop Summary Report Hi Pat, Rob, and Pradeep, I'd like to share with you a largely complete initial draft of the harvesting workshop summary report. I tried to capture the important points of the presentations and discussion at the workshop and then synthesize that down to "key takeaways" (I am open to a better term, but that's what I came up with). I still need to fill in the section on "References to Past Harvested Materials Research", but otherwise consider this a complete draft.

Please feel free to review and comment the overall organization, level of detail, etc. You can also review the specific wording with edits and tracked changes if you'd like, although I'd suggest not spending too much effort down in the weeds at this point.

My hope is to get some feedback in the next 2 weeks from this group and then share with the broader group of workshop attendees by the end of May for their review and input with a target to finalize this report by the end of June.

Thanks and please let me know if you have any questions!

Matt

Harvesting Workshop Summary Report

Background

On March 7-8, 2017, t he Office of Nuclear Regulatory Research of t he Unit ed States Nuclear Regulatory Commission (NRC) hosted a 2-day workshop on the topic of "Ex-Plant Mat erials Harvesting." NRC staff worked in close coordination with staff from the U.S. Department of Energy (DOE) and the Electric Power Research Institute (EPRI) to plan and arrange the workshop.

The decision to organize this workshop was driven by developments in the U.S. and global nuclear industry. In the U.S., there is strong interest in extending plant lifespans through subsequent license renewal (SLR) from 60 to 80 years. Extended plant operation and SLR raise a number of technical issues that may require further research to understand aging mechanisms, w hich may benefit from harvesting.

Meanwhile, in recent years, a number of nuclear plants, both in the U.S. and internationally, have shut down or announced plans to shut down. Unlike in the past when there were very few p lants shutting down, these new developments provide opportunities for harvesting components that were aged in representative light water reactor (LWR) environments. In a related development, economic challenges for the nuclear industry and limited government spending have limited the resources available to support new research, including harvesting programs. Given this constrained budget environment, aligning interests and leveraging wit h other organizations is important to allow maximum benefit and value for future research programs.

Objective and Approach The objective of t he workshop was to generat e open discussion of all aspects of ex-plant materials harvesting, including:

1. Deciding whether to harvest,

2.

Planning and implementing a harvesting program,

3.

Using t he harvested materials in research programs.

Through presentations and open discussion, the workshop was organized to allow for all participants to be better informed of the benefits and challenges of harvest ing as well as to identify potential areas of common interest for future harvesting programs. Workshop sessions were aligned in broad topics to cover all aspects of harvesting, but allow for participants to drive the discussion.

To help accomplish the workshop objectives, the workshop organizers intentionally sought a diverse group of participants. There are a large number of decommissioning plants and interested researchers outside t he U.S., so the organizers focused on outreach t o int ernational participant s t hrough connections such as IAEA, OECD/NEA, and existing professional contacts. In addition, a key goal for this workshop was to capture the broader practical perspective from plant owners and decommissioning companies, which are vital to any successful harvesting program, but may sometimes be overlooked in researcher-driven discussions. Workshop participants were also diverse in terms of technical area of focus, with metal components such as t he reactor pressure vessel (RPV) and internals being discussed along with concrete and electrical components. The final list of workshop part icipants can be found at the end of t his report in Appendix I.

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Workshop Organization and Sessions The workshop was held at NRC headquarters in Rockville, MD. Due to limited space in t he meeting room and the need for a limited group size for discussion, a webinar was used to allow remote observers to benefit from the workshop. Workshop sessions were organized topically with about half the time dedicated to presentations and the remaining time set aside for discussion. Presentations were solicited from participants to cover a range of perspectives and t echnical areas. The final workshop agenda can be found at the end of this summary report in Appendix II.

The workshop was organized into five sessions as follows:

Session 1 Motivation for Harvesting Session 2 Technical Data Needs for Harvesting Session 3 Sources of Materials Session 4 Harvesting Experience: Lessons Learned and Practical Aspects Session 5 Future Harvesting Program Planning Summary of Workshop Discussion The subsections below will summarize the presentations and discussion in each session and highlight the key takeaways from the session.

Session 1 Motivation for Harvesting Session 1 focused on t he motivation for harvesting and why workshop participants are interest ed in harvesting. Presentations were provided in t his session by:

Richard Reister from DOE, Sherry Bernhoft from EPRI, Robert Tregoning from NRC, Uwe Jendrich from the Gesellschaft fur Anlagen-und Reaktorsicherheit (GRS) in Germany, and Taku Arai from the Central Research Institute of the Electric Power Industry (CRIEPI) in Japan.

Presentation Summaries DOE described the role of harvesting within the Light Water Reactor Sustainability (LWRS) Program, including the benefits and challenges associated with harvesting. Benefits include the opportunity to fill knowledge gaps where there is limited data or experience and to inform degradation models with data from actual plant components. Challenges include cost, complexity, scheduling, logistics, limited opportunities, acquiring sufficient material pedigree information, and potential negative results impacting operating plants.

EPRI discussed the role of harvesting within the context of aging management for Long-Term Operations (LTO), including t heir experience from past hairvesting programs and criteria for future harvesting. Their experience emphasized the challenges of cost, schedule, logistics, complicated contracting and acquiring material pedigree information. EPRl's criteria for harvesting include value to t heir members that addresses a priorit ized need and knowledge gap that cannot be otherwise filled t hrough other means.

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For EPRI, a well-developed project plan t hat covers funding, risk management, exit ramps, and clear roles and responsibilities is essential.

NRC shared its perspective on the benefits and challenges of harvesting in regulatory research.

Harvest ed materials are valuable due to the representative nature of their aging conditions, which may reduce the uncertainty associated with t he applicability of the results to operating plants compared to tests with alt ernative aging conditions. Harvested materials may be t he best option to address technical data needs identified for extended plant operation. Increasing harvesting opportunities from decommissioning plants suggests a proactive approach to harvesting planning may optimize benefits by identifying t he appropriate material with t he aging conditions of int erest for the identified knowledge gap. There are significant challenges associated with harvesting, including cost, schedule, and logistics, but hopefully these can be mitigated or avoided by leveraging wit h other organizations and learning from past experience.

GRS described its role as the main technical support organization in nuclear safety for the German federal government. GRS provides technical assessment and knowledge t ransfer for decommissioning activities, aging management, and long-term operation for German federal and interna,tional organizations.

CRIEPI discussed its view of how harvested materials and laboratory prepared materials cont ribute to addressing technical issues. Harvested materials provide exposure to actual plant cond itions, but are more limited in availability and the size of the data set that can be generated. Laboratory prepared materials general involve accelerated or simulated aging conditions, but can be used to produce larger data sets and varying parameters can allow understanding of the effect on the mechanism or property of interest. Harvested materials offer fact finding of actual plant conditions as well as confirmation and verification of results from laboratory prepared specimens.

Discussion Summary The discussion follow ing the presentat ions in t his session focused on clearly ident ifying the need to be addressed by a harvesting project and the myriad cost, schedule, and logistical challenges associated with harvesting. Leveraging with other organizations to defray costs can also help improve t he value of a given program, but also adds complexity as another organization may have a different set of priorities that changes the focus of the harvesting effort.

Session 2 Technical Data Needs for Harvesting Session 2 focused on discussing the technical data needs for harvesting and what specific know ledge gaps organizations are interested in addressing t hrough harvesting. This discussion included general perspectives on how to determine w hen harvesting should be pursued rather than other types of research. Presentations were provided in t his session by:

Pradeep Ramuhalli from the Pacific Northwest National Lab (PNNL),

Matthew Hiser from NRC, Keith Leonard from Oak Ridge National Laboratory (ORNL),

Rachid Chaouadi from SCK-CEN in Belgium, and Arzu Alpan from Westinghouse.

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Presentation Summaries PNNL presented their work, under a small NRC contract, to develop a systematic approach to prioritize data needs for harvesting. PNNL proposed five primary criteria for prioritizing harvesting:

Unique field aspects of degradation o

For example, unusual operating experience or legacy materials (composit ion, etc.) that be no longer available Ease of laboratory replicat ion of environment-material combination o

For example, simultaneous thermal and irradiation conditions may be difficult to replicate or mechanism sensitive t o dose rate may not be good for accelerated aging Applicability of harvested material for addressing critical gaps o

Prioritize harvesting for critical gaps over less essential data needs Availability of reliable in-service inspection (ISi) techniques for the material/ component o

If inspection methods are mature and easy to apply to monitor and track degradation, perhaps the effort of research with harvested materials is not needed.

Availability of material for harvesting o

The necessary materials/ components must be available to be harvested.

PNNL then presented t heir application of these criteria to four materials degradation is.sues as an example: electrical cables, cast austenitic stainless steel (CASS), reactor vessel internals, and dissimilar metal welds. Based on applying these criteria to t he examples, PNNL concludes that electrical cables, CASS, and reactor internals are all higher priority for harvesting due to unique aspects of the degradation that are challenging to replicate in the lab. Meanwhile, dissimilar metal welds are of low priority due to the ease of replication in lab aging studies as well as the significant body of knowledge and research on the phenomena.

NRC presented a summary of data needs it is interested in pursuing through harvesting. These included RPV materials to validate fluence and attenuation models and to demonstrate the conservatism of regulatory approaches for transition temperature prediction. Other metal components of interest for harvesting would address data gaps in irradiated stainless steels, as well as improve understanding of inspection capabilities and fatigue life calculat ions. Electrical components of interest include low and medium voltage cables and other electrical components for degradation studies, and electrical enclosures and cables for fire research. Concrete components of interest include irradiated concrete, concrete undergoing alkali-aggregate reactions, post-tensioned structures, reinforcing steel, t endons, and spent fuel pool concrete to assess potential boric acid attack.

DOE/ORNL presented their perspective on dat a needs for harvesting and its role in providing validation of experimental and theoretical research. DOE performed a significant reactor pressure vessel (RPV) harvesting program at the Zion nuclear power plant to reduce uncertainties in the Master Curve methodology, validate modeling predictions and study flux and fluence attenuation effects. The harvesting is largely complete, but t he testing program is currently underway. DOE also indicated interest in using harvested materials to validate its models for swelling and microstructural changes of st ainless steel internals under LWR irradiation conditions. Harvesting concrete components would be of interest due to lack of literature data and the multiple dependent variables t hat may affect concrete 4

performance. Finally, DOE has been involved in harvesting cables from the Crystal River and Zion plants to address cable aging as a function of material composition and environment.

SCK-CEN presented their interest in a international cooperative program to harvest reactor pressure vessel (RPV) materials. SCK-CEN presented their survey of the literature for past testing programs of harvested RPV materials, and the limitations of these past program. Key limitations include a lack of archive materials, generally lower temperatures, and poor surveillance programs and dosimetry. SCK-CEN then shared some thoughts on t heir criteria for a new harvesting efforts, including higher fluence levels and temperatures, available archive materials and reliable information on operating history, dosimetry and surveillance program. Other topics relevant to a new RPV harvesting effort include technical issues such as material variability and irradiation condit ions as well as logistical and financial considerations.

The final presentation in Session 2 by Westinghouse focused on the need for harvesting irradiated concrete to better understand the threshold radiation level for significant strength reduction.

Westinghouse has installed ex-vessel neutron dosimetry (EVND) at a number of plants in the world and proposed to use these dosimetry measurements to validate fluence model calculations to better understand the uncertainty in these calculations. If concrete can be harvested at one of these plants with EVND data, then irradiated concrete properties from testing can be paired with fluence data to improve research benefits.

Discussion Summary Dosimetry capsules Westinghouse

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f Support bar The discussion following Session 2 presentations touched on a number of topics. EPRI shared that they developed a report related to the topics of session 2, but more narrowly focused on PWR internals.

MRP-320, "Testing Gap Assessment and Material Identification for PWR Internals," focuses on prioritizing opportunistic harvesting of stainless steel reactor internals components t ha,t may be removed from service following MRP-227 inspections. The methodology and approach in this report may be relevant to the broader harvest ing data needs discussion. This report is not publicly available, but is available to EPRI member utilities.

Workshop participants discussed the criteria proposed by PNNL in the first presentation. One additional criteria suggested by EPRI was to consider fleet-wide vs. plant-specific applicability. More broadly applicable materials would be of greater interest for harvesting than those that represent conditions at only a few plants. Another criteria suggested is the availability of material pedigree information, such as composition, processing, environmental conditions (temperature, humidity, fluence, etc.). Another suggested criteria was the ease of harvesting. For example, highly irradiated internals are probably much more difficult and expensive to harvest than electrical cables or unirradiated concrete. This discussion would capture the idea of weighing costs vs. benefits as well as project risk. Further discussion touched on the idea that different organizations may prioritize the various criteria differently, but all will probably at least want to consider the same set of criteria.

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Another key theme from this discussion was t hat a successful program should be guided by a clearly defined objective or problem statement to be addressed. This objective should be well-understood at the initiation of a program and used to guide decision-making through implementation of a harvesting project. This also raises a related point or potential criteria: the timeliness of the expected research results relative to the objective. If t he results are needed in the next two years, but a harvesting project will not provide results for at least five years, t hat should be a strong consideration.

Session 3 Sources of Materials Session 3 focused on discussing sources of materials for harvesting. This discussion covered previously harvested materials as well as sources for new harvesting programs from operating or decommissioning plants. Both domestic and international sources of materials were discussed in t his session.

Presentations were provided in this session by:

Matthew Hiser from NRC, Al Ahluwalia from EPRI, Tom Rosseel from DOE/ORNL, John Jackson from DOE/Idaho National Laboratory (INL),

Gerry van Noordennen from EnergySolutions, Arzu Alpan from Westinghouse, Uwe Jendrich from GRS, and Daniel Tello from the Canadian Nuclear Safety Commission (CNSC).

Presentation Summaries NRC presented their perspective on sources of materials for harvesting. First, NRC shared some of the harvested materials from past research programs t hat may be available, including irradliat ed stainless stee l internals, RPV materials, nickel alloy welds, neutron absorber material, and electrical components.

NRC then summarized the recently and planned shutdown U.S. plant s, including their design, thermal output, and years of operation, to provide participants wit h an idea of the potential sources from decommissioning U.S. plants. Finally, NRC shared a list of information that would be helpful to acquire from decommissioning plants to determine the value of components for harvesting. This information included plant design information (component location and dimensions), environmental conditions (temperature, fluence, humidity, stress, etc.) and operating history, material pedigree information (fabrication records), and inspection records (for interest in components with known flaws).

The next presentation from EPRI covered harvesting opportunities at decommissioning plants in Korea and Sweden. In Korea, Kori-1 is a Westinghouse 2-loop PWR (sister plant is Kewaunee) that will shut down in 2017 after 40 years of operation. Korea Hydro and Nuclear Power Central Research Institute (KHNP-CRI) is planning a comprehensive research program on long-term materials aging based on harvesting from Kori-1 and is seeking international participation in the harvesting effort. KHNP-CRl's plan is focused on metallic components, including RPV, internals, primary system components, steam generator materials. Harvesting is expected to occur in 2024 with testing to follow through 2030.

In Sweden, Vattenfall is currently harvesting in 2017-2018 RPV material from the decommissioning Barseback BWR units. This work is focused on irradiation embrittlement, including comparison of 6

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(b )( 4) surveillance data to actual RPV properties, as well as thermal aging embrittlement. In the future, Vatt'enfall will be shutting down Ringhals 1 and 2 in 2020 and 2019, respectively. Ringhals 1 is a BWR and Ringhals 2 is a Westinghouse 3-loop PWR design. Of particular note, Ringhals 2 has the second oldest replaced Alloy 690 RPV head and steam generators. Other harvesting opportunities at Ringhals include RPV material with a significant surveillance program, thermal aging effects on low alloy steel from the pressurizer, as well as concrete structures. Vattenfall is open to working with partners that are interested in joining them for harvesting at Ringhals.

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The next presentation by DOE/OR NL focused on several harvesting programs that DOE's LW~_S.prCigram has been involved wit h. DOE has led t he harv*esting of component s from the Zion!

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the U.S. From Zion, DOE has harvested electrical cables and components, a large RPV section, and a sign ificant amount of records to provide information on material fabrication, in-service inspection and operating history. Cables from Zion include CROM, thermocouple, and low and medium voltage cables.

DOE indicated some thermocouple cables from Zion may be available for other researchers t o use in collaborative studies.

__,DOE is also participating in efforts to harvest cables from Crystal River (led by EPRI) and concrete from the Zorita plant in Spain (led by NRC).

The next presentation by DOE/I NL described I NL's Nuclear Science User Facilities (NSUF) and the Nuclear Fuels and Materials Library (NFML). NSUF Is coordinated by INL and facilitates access to nuclear research facilities around the world, including neutron and ion irradiations, beamlines, hot cell testing, characterization and computing capabilities, NFML is a Web-based searchable database sample library that captures the information from thousands of specimens available to NSUF. NFML is designed to maximize the benefit of previously irradiated materials for future research. Researchers can propose new research projects under NSUF using specimeros in N FML using DOE funding, The information captured in NFML aligns well with t he goal of this session to potentially develop a database of previously harvested materials.

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The next presentation by EnergySolutions offered a more practical perspective on considering sources of materials for harvesting. From the plant owner perspective, in the decommissioning process there is not a firoancial incentive to support harvesting, t herefore researchers need to absorb costs for harvesting and have a clear scope for harvesting. Flexibility in funding for harvesting activities is essential as the decommissioning process and schedule may change quickly.

EnergySolutions provided valuable perspective on the timing in the decommissioning proves for harvesting different components. Harvesting RPV surveillance coupons should take place when the RPV internals are cut and removed. Harvesting RPV materials is only possible from larger RPVs, as smaller RPVs are shipped intact to the disposal facility, rather than cut into pieces. Spent fuel rack neutron 7

absorber coupons must be harvested eit her before or after dry storage campaign to remove spent fuel from spent fuel pool. Harvesting actual spent fuel rack neutron absorber material must come after pool is completely empty. Electrical cables and other components from mild environments may be harvested at any t ime (once temporary power is established and plant power is shut off), while electrical components from high rad environments will depend on timing of source term removal schedule.

Concrete cores are best harvested when other cores are being taken for site characterization to develop the License Termination Plan. Highly irradiated concrete from biological shield wall would need to come later in decommissioning after RPV is removed.

In terms of upcoming decommissioning plants, EnergySolutions indicat ed that San Onofre and Vermont Yankee will be entering DECON is 2018 and 2019, respectively. Kewaunee, Crystal River, and Fort Calhoun also may enter DECON in next 2 years. If researchers are interested in harvesting from any of these plants, they should be reaching out to plant owners immediately to begin planning and coordination.

Westinghouse followed their presentation in session 2 by describing an opportunity to harvest concrete from the Mihama 1 plant in Japan. Westinghouse installed and analyzed additional neutron dosimetry in the reactor cavity for one cycle, which were used to validate t he radiation t ransport calculations.

Mihama was shutdown in 2015 and is in contact with Westinghouse about the possibility of extracting concrete cores from the biological shield wall. Westinghouse is seeking partners interested in joining this harvesting effort.

The next presentation by GRS covered opportunities for harvesting from German plants. Regulations in Germany require plants to either immediately dismantle or dismantle after a period of safe enclosure, which is largely consistent with options in the U.S. GRS detailed the status of German commercial reactors, which are predominantly BWR and PWR designs. Seventeen reactors are currently undergoing decommissioning, while seven more are currently shutdown and await a decommissioning license. Eight reactors are still operating with scheduled shutdown dates between 2017 and 2022. German RPVs tend to have lower fluence that U.S. designs due to a larger water gap in the downcomer region. Germany has limited experience wit h harvesting from decommissioning plants. One question that GRS will follow-up on is the "rumored" cable surveillance programs that may be used in Germany and could provide experience and lessons learned for other countries.

The final presentation in Session 3 was by CNSC on harvesting opportunities in Canada. Atomic Energy Canada Limited (AECL) has harvested seven concrete cores from the 20 MW Nuclear Power Demonstration Plant (NPD), which shutdown in 1988 after 25 years of operation. CNSC and AECL are also considering opportunities to harvest concrete from other decommissioned reactors in Canada such as Gentilly-2, Douglas Point, and Whiteshell Reactor 1. In addition to concrete, CNSC arnd AECL are current ly harvesting electrical cables from the 675 MWe CANDU-6 Gentilly-2 reactor, which shutdown in 2012 after 29 years of operation. The purpose of this work is to study cable degradation from thermal aging and radiation damage and validate environmental qualification of the cables. CNSC described some of the challenges with t his harvesting effort, such as working wit h plant owners, records, accessibility and cont amination of the materials and budgeting with unexpected delays in harvest ing.

A future harvesting opportunity is from the National Research Universal (NRU) reactor at Chalk River, which will shut down in 2018 after operating since 1957. AECL is currently taking an inventory of irradiated materials that can be harvested from NRU in decommissioning. Potential materials for 8

harvesting include metals (steels, nickel alloys, zirconium, aluminum), concret e, graphite, active equipment (pumps, etc.), graphite seals, electrical cables, and thermocouples.

Discussion Summary Following t he presentations, there was some discussion of lessons from DOE's Zion harvesting effort.

DOE worked with a former senior reactor operator at Zion to identify and acquire t he a,ppropriate records from Zion for the components being harvested. DOE also described their flexible approach to acquiring RPV samples by sending a large chunk of mat erial (weighing ~90 tons) to EnergySolutions' facility in Tennessee, where smaller pieces (weighing ~soo pounds) were cut to send to ORNL. Most of the decontaminat ion was performed at Zion, w it h minimal additional cleaning (as well as cladding removal) taking place at EnergySolut ions' facility.

There was also discussion of acquiring materials from sources other than commercial nuclear facilities.

DOE has considered harvesting concrete from other DOE nuclear facilities, but determined that there were compositional differences between the DOE facilities and commercial that would make them not useful. DOE/INL mentioned that the Advanced Test Reactor (ATR) replaces their core internals every ten years. The ATR internals are composed primarily of 347 stainless steel and achieve very high fluence leve Is after ten years of service.

Another key discussion topic was the possibility of developing a database for previously harvest ed materials or those available for future harvesting. DOE/I NL indicated that their NSUF sample library may be a good starting point for such a database, although any materials in t hat library should be freely available for use in the research community. CNSC and NRC also expressed interested in working to develop a harvesting database.

Session 4 Harvesting Experience: Lessons Learned and Practical Aspects Session 4 focused on lessons learned and practical aspects of harvesting. Presenters shared t heir experience with past harvesting programs, particularly common pitfalls to avoid and successful strategies to overcome them. Presentations also covered the practical aspects of harvesting from the plant owner and decommissioning company perspective.

Presentations were provided in this session by:

Jean Smith from EPRI, Tom Rosseel from DOE/ORNL, Matthew Hiser from NRC, Taku Arai from CRIEPI, Gerry van Noordennen f rom EnergySolutions, and Bill Zipp from Dominion.

Presentation Summaries EPRI presented their experience and lessons learned from past harvesting programs, particularly harvesting reactor internals and concrete from Zorita and electrical cables from Cryst al River. From the Zorita reactor internals experience, EPRI emphasized that harvesting projects take significan t ime, encounter material retrieval and on-site challenges, and shipping issues. In terms of time, ZIRP took 9

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about 10 years to go from initial planning to final results, which included about 5 years of project planning, 2 years for material extraction (on-site logistics and shipping), and 3-4 years for testing. EPRl's experience was decommissioning activities were the top priority and harvesting were subject t o schedule and logistical challenges based on t he changing decommissioning schedule. Shipping issues were also challenging due to sending activated materials (which were classified as "waste") across international borders, from the reactor in Spain Zorita Internals Research Project Timeline to testing facility in Sweden. Further planned shipments of the Zorita materials beyond the

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initial program continue to be impact by export license challenges in Sweden. More positively, EPRI emphasized that the Zorita reactor internals materials harvesting showed excellent

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Lessons learned from the Zorita concrete harvesting focused on the challenges with core sample drilling and handling contaminated concrete. Ultimat ely, an effective core drilling procedure w as identified, but required some trial and error.

Lessons learned from the Crystal River cable harvesting included material concerns, the need for on-site support, and cost. In terms of material concerns, radiation and asbestos contamination created additional challenges for harvesting. On-site support and t he ability to visit the site are extremely valuable to ensure clear communication, retrieval or records for material pedigree information, and awareness of on-site developments in the decommissioning process. Cable harvesting at Crystal River was more expensive than anticipated, part icularly in terms of EPRI project management time to coordinate the harvesting activities and engineering support at the plant.

DOE presented lessons learned primarily from the experience harvesting RPV materials and electrical cables and components from the Zion plant. In terms of planning and decision-making, DOE had several lessons learned. DOE hosted a workshop at Zion in 2011 to discuss long-term goals and objectives, which proved very helpful in setting priorities and developing partnerships with other organizations.

Partnerships were very valuable to DOE's harvesting efforts, allowing for leveraging resources and collaboration and sharing results. There are limited opportunities for harvesting key components, so take full advantage of the opportunities that arise, understanding that t here is a necessary compromise between the materials available and their value in terms of fluence or exposure to aging conditions.

Another consideration is the quantity of material harvested, which should be sufficient for the objectives of the planned research as well as any collaborations or partnerships, but limited t o control costs.

For implementing the harvesting program, DOE found that flexibility was paramount to be able adjust scope and plans in response to schedule changes and other development s, while remaining within cost constraints. Working with a former reactor operator was extremely valuable to benefit from their in-depth knowledge of all parts of the plant, in particular the records for materials pedigree information.

Regular sit e visits and contacts were also essential t o stay aware of the lat est developments in the harvesting planning and decommissioning process, with the understanding that harvesting is not t he top priority for decommissioning company. Other important considerations were hazardous materials 10

(b )(4) handling, t ransportation, and disposal and logistics, including contracts, liability, shipping and disposal.

Finally, DOE's experience is t hat the total cost s of a harvesting program from planning t o execution to testing are very high, so they should be carefully weighed against the value of the expected data to be generated.

NRC presented their experience, including benefits from previous harvesting programs, and technical and logist ical lessons learned from harvesting. As an organizat ion, NRC has extensive experience with testing harvested materials, including RPV, primary system components, reactor internals, neutron absorbers, concrete and electrical component s. NRC's experience is more limited than DOE or EPRI in terms of managing the logistics of a harvesting effort from a decommissioning plant. NRC has generally participated in a secondary role in cooperative efforts or received failed components from operating plants for research. NRC has found t hat previous harvesting efforts have been effective in reducing unnecessary conservatism, understanding in-service flaws more realistically for NOE ar.d leak rate methodologies, as well as ident ifying and better understanding safety issues.

For technical lessons learned, NRC's perspective is that harvesting can provide highly representat ive aged materials for research, which may be the only practical source of such materials. Harvested materials can be effectively used to validate models or a larger data set from accelerated aging tests. It is important understand as much as possible about the materials and their environment in service and how this compares with the operating fleet of reactors before committing to a specific harvesting project. For logistical lessons learned, harvest ing is expensive and time-consuming, so a high technical benefit is ne+eded to ensure the program provides values. Leveraging with other organizations can help mini mize costs, but can also introduce challenges for aligning priorities and interests of multiple organizatiom. Finally, transporting irradiated materials, particularly between countries, challenging an time-consuming and should be avoided if at all possible.

~RIEPI presented t heir research experience with harvested materials as well as ongoing harvesting from the Hamaoka 1 plant. The first research program involved atom probe tomography (APT) on RPV surveillance materials. CRIEPI found a correlation between t he volume fraction of Ni-Si-Mn clusters and the change in nil-ductility temperature. In the second research project, CRIEPI characterized the weld and base materials harvested from Greifswald Unit 4 RPV with small-angle neutron scattering, APT, and hardness testing. In t he third research project, CRIEPI performed APT on 304L stainless st eel reactor internals harvested from control rod and top guide components from 3-13 dpa. Results showed a strong increase in Ni-Si clusters with increasing fluence, but little variat ion in Al enriched clusters with increasing fluence. I For future work, CRIEPI is collaborating with DOE LWRS to investigat e RPV mat erials harvested from Zion

...._ _____________ _,CRIEPI also presented activities underway by Chubu

• • Electric Power to harvest RPV and concrete samples from the Hamaoka 1 plant. Hamaoka 1 is a 540 MW BWR-4 that operated for 33 years. Harvesting began in 2015 and will continue through 2018.

The final two presentations of Session 4 provided the non-researcher perspective from a decommissioning company and plant owner. EnergySolutions, which is decommissioning the Zion nuclear plant among other facilities, presented the decommissioning process and their experience and lessons learned from harvesting at Zion. As mentioned previously, surgical harvesting Is not the top priority for decommissioning, so researchers must recognize this and coordinate close with the decommissioning company. EnergySolutions emphasized the need to gain senior management support 11

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at t he plant as well as t o expect that there may be staff turnover during a multi-year harvesting effort.

Changes in scope and schedule (originating from both sides) can cause frustration on both sides. [Early planning and delays with contracting are important to avoid lost opportunities. Being on-site during harvesting is essential to a good outcome.

At Zion, EnergySolutions worked with DOE to harvest RPV materials, cables, electrical components, and spent fuel storage racks. DOE hoped to harvest a particular RPV surveillance capsule, but was unable to due to the inability identify the correct capsule. There were also challenges with harvesting RPV materials. The cut line on the Unit 2 RPV was too close to the weld to be used for research; fortunately, a successful specimen was harvested from Unit 1. For cabling, the init ial plan was t o harvest from 11 different locations, but ultimately due to unforeseen challenges and poor communication and coordination, only 4 different cable locations were harvested. Harvesting the desired cable length (30 feet) also proved challenging, with only shorter sections recovered. Plant records searches were largely effect ive at providing material pedigree information for cables. Concrete coring was initially planned to take place at Zion, but not performed due to lack of research interest. The spent fuel storage rack harvesting went smoothly, which was assisted by efforts over t he weekend when decommissioning activities were not occurring.

The next presentation from Dominion provided its perspective on harvesting from decommissioning plant s, focused on t he experience at Kewaunee Power Station. The top priority (beyond safety) in decommissioning is t he preservation and good stewardship of the decommissioning trust fund. Staffing is the largest drain on t he trust fund, so at Kewaunee staff was halved within a few months of shutdown and then halved again about 16 months after permanent shutdown once offsite emergency response requirements were eliminated. Dominion described the example of harvesting the RPV surveillance capsules at t his point at Kewaunee and the significant challenges that would exist. Given the reduced staffing and the current plant state (reactor coolant system drained, pumps retired, crane and radiation monitoring not maintained), it would be much more difficult now than immediat ely after shutdown.

Kewaunee considered harvesting the surveillance specimens and estimated a cost of six to seven figures based on all the activities required to enable it at this point post-shut down compared to a much lower cost just after shutdown. Dominion observed that some components, such as cables or electrical components, may be available and relatively easy to harvest at almost any time during decommissioning. However, other components such as highly irradiated internals or RPV may be best harvested either shortly after shutdown when staffing and capabilities on-site are high or wait until active demolition of t he reactor, which may be years or decades later.

Dominion also touched on t he discussion of records for plant components. Records requirements are limited to those needed for safety. Once the plant shuts down and the range of potential safety concerns decreases, systems are downgraded to non-safety and t he associated records are no longer required to be maintained. For perspective, Kewaunee still has all its records four years since shutdown, but will likely not continue this much longer. Dominion closed its presentation with a broader perspective on harvesting, emphasizing the need t o clearly define a problem statement and understand what technical and regulatory purpose this harvesting will serve. Early planning focused on achieving the clear objective of the work including scope, schedule, budget and contact with plant is essential to a successful harvesting effort.

12 (coili"mented [PP,4]: reword

Discussion Summary The discussion touched on the top lessons learned from past harvesting efforts, which included a clear objective and purpose for harvesting, early engagement with the plant, and site coordination during harvesting.

Another suggestion was to get utility management buy-in for the harvesting project by identifying a benefit to the utility. EPRI mentioned that cable harvesting at Crystal River went much more successfully once the utility recognized the potential benefits for subsequent license renewal. Similarly, when harvesting from an operating plant, you need to recognize and work through the challenges the plant may encounter when restarting operations.

During discussion, the question was raised regarding how it is determined whether harvested materials are w aste. The discussion concluded that in the U.S. 10 CFR 37 is the important consideration. 10 CFR 37 defines when additional security requirements are imposed, based on the quant ity and act ivity of materials to be transported. The definition of material as waste versus research materials is not as critical in the U.S. EnergySolut ions indicated t hat t heir shipments of waste or research material could be handled in the same way in the accordance w ith Department of Transportation regulations, provided that the limits in 10 CFR 37 were not reached.

Session 5 Future Harvesting Program Planning Session 5 focused on t he information needed for informed harvesting decision-making and harvesting program planning. This session featured a presentation by Pradeep Ramuhalli from PNINL, followed by a discussion period covering harvesting program planning and reflection on the 2-day workshop.

Presentation Summary PNNL presented its perspective on t he information needed for informed harvesting decision-making.

First, the purpose of t he harvesting effort needs to be defined by identify the t echnical knowledge gaps to be addressed. Next, a research plan should be developed demonstrating how the harvested material will be used to address the identified gaps. Finally, t he appropriate source of material to address the technical gap must be identified, along with resources to support the effort and plans and t imelines to perform the harvesting. The specifics of these plans depend great ly on the source of materials and must be flexible based on changing conditions on the ground.

In assessing the best source of materials, researchers should consider t he material, its environment, and its condition. Material information includes fabrication information such as manufacturer, composition, and dimensions as well as information related to installation or construction, such as welding processes and parameters. Environmental information includes temperature, humidity, fluence, flux, stress (service, residual, installation), and coolant ct-.emistry. Component condition information includes inspection history, such as identified flaws or degradation.

Discussion Summary The discussion in Session 5 focused on t he best practical approach to plan future harvesting programs.

There was clear agreement that t his approach must begin with identifying t he data needs best 13

addressed by harvesting, whether from opera,ting or decommissioning plants. Once a specific need is identified, the next step is to find a source to acquire the materials of interest as well as other organizations interested in participating in the harvesting effort.

[Key Takeaways from Workshop Session 1 The clear takeaway from the discussion in session 1 was t hat harvesting requires significant resources to be done successfully; therefore it is paramount to identify how t he planned harvesting will clearly address a significant need to ensure t he harvesting project provides strong value. In the context of need for data, EPRI suggested t he goal of harvesting to support research for operation out to 80 years is not a full comprehensive understanding of all aspects of t he degradation, but rather a snapshot to confirm other lab results and models. This is an Important point for all organizations and researchers to keep in mind before investing significant resources in harvesting.

The criteria proposed by PNNL are a good st arting point for prioritizing issues to address by harvesting.

Three additional important criteria would be:

Fleet-wide vs. plant-specific applicability of data, Ease of harvesting (in terms of cost and project risk), and Timeliness of the expected research results relative to the objective.

Once a potential harvesting project has reached the point of looking at different sources of materials, the availability of material pedigree information, such as composition, processing, environmental conditions (temperature, humidity, fluence, etc.) is very important to the overall value of harvesting from that particular plant.

Based on t he presentations and discussion in Session 2, there appeared to be two areas with broad interest in pursuing further harvesting: high fluence reactor internals and irradiated concrete. The common drivers for the interest in these issues is a lack of representative data at t he fluences of interest and significant challenges with acquiring representative data through other means. High fluence reactor internals has been addressed somewhat by t he Zorita Internals Research Project (ZIRP), but stainless steel materials exposed to higher fluence levels at higher temperatures, where void swelling may become significant, could help validate DOE and EPRI models and provide further technical basis for PWR internals aging management. Irradiated concrete harvesting is currently being pursued from the Zorita reactor in Spain, with international collaboration and potential testing at the Halden Reactor Project.

Other areas with some, but less widespread, interest expressed from workshop participants for new harvesting efforts included RPV materials and electrical cables and components. SCK-CEN and NRC expressed interest in RPV harvesting, and NRC expressed interest in electrical component harvesting.

Session 3 14 Commented [PPS]: I think some of the information would be better In t he previous sections for sessions

• l *S.

We may not really need this, think about lt.c

To capture the key takeaways from Session 3 focused on sources of materials, two tables of potential sources of materials are presented below. The first table covers recent or ongoing harvesting programs, while the second details potential future harvesting opportunities.

Ong*oing Harvesting Programs Country Plant Design Size Years in Components Organlzation(s)

(MWe) operation Canada NPD CANDU 20 25 Concrete AECL Gentilly-2 CANDU-6 6,75 29 Cables Japan Hamaoka 1 BWR-4 540 33 RPV, concrete CRIEPI/Chubu Soain Zorita W 1-looo 160 37 Internals, concrete EPRI, NRC Sweden Barseback ABB-II 6,15 28 RPV Vattenfall Zion 1/2 W -4 1040 24/25 RPV, cables, DOE, EPRI, NRC loop neutron absorbers U.S.

Crystal River 3 B&W 860 36 Cables EPRI (b )(4)

Potential Future Sources for Harvesting Country Plant Design Size Years In Potential Notes (MWe) operation Components Canada NRU Test reactor 135 61 TBD AECL; SD:

MWt 2018 Germany Numerous plants either in decommissioning or shutting down soon. See Appendix Ill.

Japan Mihama W 2-loop 320 40 Concrete

Kansai, Westinghouse RPV, internals, Korea Kori 1 W 2-loop 576 40 SGs, pressurizer, KHNP, EPRI welds, CASS, Ringhals 1 BWR 883 44 RPV, internals Vattenfall; Sweden Ringhals 2 W 3-loop 900 44 SGs, pressurizer, SD: 2020 /

concrete 2019 Kewaunee W 2-loop 566 39 TBD SD: 2013 SONGS 2/3 CE 2-loop 1070 31/30 TBD SD: 2013 Crystal River 3 B&W 860 36 TBD SD: 2013 Vermont BWR-4/Mk-1 605 42 TBD SD: 2015 Yankee Fort Calhoun CE 2-loop 482 43 TBD SD: 2016 U.S.

Palisades CE 2-loop 805 47 TBD SD: 2018 Pilgrim BWR-3/Mk-1 677 47 TBD SD: 2019 Oyster Creek BWR-2/Mk-1 619 so TBD SD: 2019 Indian Point W 4-loop 1020 /

48/46 TBD SD: 2021 2/3 1040 Diablo Canyon w 4-loop 1138/

40 TBD SD: 2024-5 1/2 1118 15

Non-Advanced 250 commercial; Test reactor so Core internals internals Test Reactor MWt replaced every 10 years In addition to the potential sources of materials presented and discussed in Session 3, another takeaway was the suggestion of developing a database for previously harvested materials or those available for future harvesting. The NSUF sample library may be a good starting point for such a database, with appropriate modifications for the purposes of harvesting efforts.

Session 4 There were several important takeaways from Session 4 that were touched on in multiple presentations and the discussion. One key takeaway is that researchers should identify a clear purpose and scope for harvesting. Having a clear purpose for harvesting helps to guide later decisions t hat must be made to adjust course when the inevitable changes in schedule or unexpected realities at t he plant arise. A relat ed note is t hat harvesting is not the top priority for decommissioning. Therefore, researchers must have clear objectives and scope for harvesting that can be communicated to t he site. This understanding should shape assumptions and interactions with the plant owner or decommissioning company as well as planning for costs and schedule.

Another takeaway was the value of strong site coordination, including site visits. Multiple presenters touched on the value of being on-site to talk to staff and see the components to be harvested. Mockups and 3-0 simulations can be valuable to ensure success of the approach or technique used to acquire the specimen. A related point is working with reactor operators at the plant. Several harvesting efforts worked with former reactor operators and benefited greatly from their experience to find records or determine the best method to harvest the desired component. This is a valuable insight that could be effective in future harvesting efforts.

A third key takeaway is early engagement with the plant to express interest in harvesting. This serves to make the plant aware of your interest in harvest ing and get their support to work with t he harvesting process. The other important benefit of early engagement is to gain as much informat ion as possible about the available materials and components, including t he associated records and material pedigree information.

Session 5 The key t akeaway in session 5 was to gather as much information as possible in advance of committing to a specific harvesting project. Ideally, there would be a strong understanding that the material and its aging conditions clearly align with an identified technical data need before committing significant resources to a harvesting effort.

Action Items and Next Steps The following is a summary of the action items discussed at t he end of the workshop:

1. Sharing workshop slides 16

NRC emailed attendees to ask their comfort wit h sharing their workshop slides with other organizations and received no objection from any presenters.

The presentations can be accessed here:

https://drive.google.com/open?id=0BSDWMLchSYSXcnpZZ0JOS0SSQUU.

2.

EPRI indicated that MRP-320 (Product ID: 1022866) on knowledge gaps for irradiated austenitic stainless steel for potential harvesting from MRP-227 inspections is publicly available for a fee.

3. Cable surveillance programs in Germany GRS to inquire with cable colleagues and share any insights.

4. Sources of materials database Potential sources of materials presented in this workshop are summarized in Session 3 summary above and Appendix Ill below.

NRC will be reaching out to PNNL, INL NSUF, CNSC, AECL, and any other organizations interested in database development.

5.

Priorit ized data needs Suggestion to continue discussions on prioritized data needs within technical areas (RPV, internals, electrical, concrete) through existing coordination groups if possible Focus on identifying specific material/ aging conditions of interest and purpose

/ intended outcome of harvesting Idea to survey Env Deg participants John Jackson (INL) is o n planning committee

6. EPRI report on spent fuel liner boric add transport through concrete NRC will contact EPRI for report if needed.

7.

Harvested Materials Research Results Section of workshop summary report (below) devoted to references from harvested materials research.

References to Previous Harvested Materials Research This section of the workshop summary addresses a question that was raised during the* discussion at t he workshop regarding what the outcome or benefit of past harvesting efforts have been. Below Is a list of references to research results generated from testing of harvested materials:

J.R. Hawthorne and A.L. Hiser, Experimental Assessments of Gundremmingen RPV Archive Material for Fluence Rate Effects Studies, NUREG/CR-5201 (MEA-2286), U.S. Nuclear Regulatory Commission, October 1988.

G. J. Schuster, S. R. Doctor, A.F. Pardini, and S.L. Crawford, Choracterizotion of Flows in U.S. Reactor Pressure Vessels: Validation of Flaw Density and Distribution in the Weld Metal of the PVRUF Vessel, NUREG/CR-6471 Volume 2, U.S. Nuclear Regulatory Commission, August 2000.

17

G. J. Schuster, S. R. Doctor, S.L. Crawford, and A. F. Pardini, Characterization of Flaws in U.S. Reactor Pressure Vessels: Density and Distribution of Flaw Indications in the Shoreham Vessel, NUREG/CR-6471 Volu me 3, U.S. Nuclear Regulatory Commission, November 1999.

D.E. McCabe, et al. Evaluation of WF-70 Weld Metal From the Midland Unit 1 Reactor Vessel, NUREG/CR-5736 (ORNL/TM-13748), U.S. Nuclear Regulatory Commission, November 2000.

B. Alexandreanu, O.K. Chopra, and W.J. Shack, Crack Growth Rates in o PWR Environment of Nickel Alloys from the Davis-Besse and V.C. Summer Power Plants, NUREG/CR-6921 (ANL-05/55), U.S. Nuclear Regulatory Commission, November 2006.

S.E. Cumblidge, et al. Nondestructive and Destructive Examination Studies on Removed-from-Service Control Rod Drive Mechanism Penetrations, N UREG/CR-6996, U.S. Nuclear Regulatory Commission, July 2009.

S.E. Cumblidge, et al. Evaluation of Ultrasonic Time-of-Flight Diffraction Doto for Selected Control Rod Drive Nozzles from Davis Besse Nuclear Power Plant, PNNL-19362, Pacific Northwest National Laboratory, April 2011.

S.L. Crawford, et al. Ultrasonic Phased Array Assessment of the Interference Fit and Leak Poth of the North Anno Unit 2 Control Rod Drive Mechani:sm Nozzle 63 with Destructive Volidotion, NUREG/CR-7142 (PNNL-21547), U.S. Nuclear Regulatory Commission, August 2012.

18

Appendix I Workshop Participants Name Orll!anization Email Taku Arai CRIEPI arait@crieoi.denken.or.io Sadao Higuchi CRIEPI h iguch i@crieQl.den ken.or. i Q Japan Kazunobu Sakamoto JNRA kazunobu sakamoto@nsr.go.jQ Yasuhiro Chimi JAEA chimi.~asuhiro@jaea.go.jQ Uwe Jendrich GRS Uwe.Jendrichirrs.de Europe Rachid Chaouadi SCK-CEN rachid.chaouadi@sckcen.be Guy Roussel Bel V gu~.roussel@Belv.be Daniel Tello CNSC daniel.t ello@canada.ca Canada Desire Ndomba CNSC desire.ndomba@canada.ca Karen Huynh AECL khu~nh@aecl.ca Gerrv van Noordennen Enere:v Solut ions e:ovannoordennenenere:vsolutions.com us Bill Zipp Dominion william.f.ziQQ@dom.com industry Mark Richter NEI mar@nei.org Arzu Alpan Westinghouse a1Qanfa@westinghouse.com Sherrv Bernhoft EPRI sbernhoft@epri.com Robin Dyle EPRI rd~le@eQri.com EPRI Jean Smith EPRI jmsmith@eQri.com Al Ahluwalia EPRI kahluwal@eQri.com Tom Rosseel ORNL rosseeltm@ornl.e:ov Rich Reister DOE Richard.Reister@nuclear.energ~.gov Keith Leonard ORNL leonardk@ornl.gov DOE M ikhail A. Sokolov ORNL sokolovm@ornl.gov John Wagner INL john.wagner@inl.gov John Jackson INL john.jackson@inl.gov Pradeep Ramuhalli PNNL PradeeQ.Ramuhalli@Qnnl.gov Pat Purtscher NRC Patrick. Pu rt sch e rt@n re.irov Rob Tregoning NRC Robert.Tregoning@nrc.gov Matt Hiser NRC Matthew.Hiser@nrc.gov M ita Sircar NRC Madhumita.Sircar@nrc.gov Tom Koshy NRC Thomas.Kosh~@nrc.gov NRC Jeff Poehler NRC Jeffre~.Poehler@nrc.gov Allen Hiser NRC Allen.Hiser@nrc.gov Angela Buford NRC Angela.Buford@nrc.gov Mark Kirk NRC Mark.Kirk@nrc.gov Amy Hull NRC Am~.Hull@nrc.gov Pete Ricardella NRC/ACRS Priccardella@Structint.com 19

Session Time Intro 8:00 1

8:15-8:45 8:45-9:45 9:45-10:00 10:00-10:20 10:20 -

10:30 10:30-10:55 2

10:55-11:20 11:20 -

11:45 11:45 -

12:30 12:30- 2:00 2:00 - 2:10 2:10 - 2:35 2:35 - 2:50 2:50-3:00 3:00-3:15 3

3:15-3:30 3:30-3:45 3:45-4:00 4:00 - 4:15 4:15-5:00 Appendix II Workshop Agenda Tuesday, March 7 Oreanization Soeaker Presentation Title NRC Michael Weber Welcome and Introduction to Workshop Robert Tregoning DOE Rich Reister DOE Perspectives on Material HarvestinR EPRI Sherry Bernhoft EPRI Perspective on Harvesting Projects NRC Robert Tregoning NRC Perspective on Motivation for Harvesting GRS Uwe Jendrich Role of GRS in Decommissioning and LTO CRIEPI Taku Arai CRIEPI Motivations for Harvested Material DISCUSSION BREAK PNNL (for NRC)

Pradeep Ramuhalli Data Needs Best Addressed By Harvesting NRC Matthew Hiser High-Priority Data Needs for Harvesting DOE Keit h Leonard LWRS Program Perspective on the Technical Needs for Harvestine Review of past RPV sampling test programs SCK-CEN Rach id Chaouadi and perspective for long t erm operation Westinghouse Arzu Alpan Importance of Harvesting to Evaluate Radiation Effects on Concrete Prooerties DISCUSSION LUNCH NRC M atthew Hiser Sources of Materials: Past NRC Harvesting and U.S. Decommissioning Plants EPRI Al Ahluwalia Harvesting Plans for Materials Aging Degradation Research in Korea and Sweden DOE/ORNL Tom Rosseel Materials Harvested by the LWRS Program DOE/INL John Jackson NSUF M aterial Samole Librarv Energy Solutions Gerry van Zion Material Harvesting Program Noordennen Potential Harvesting of Concrete from M ihama Westinghouse Arzu Alpan Unit 1 BREAK GRS Uwe Jendrich Plants in Decommissioning in Germany Evaluating Structures, Systems & Components CNSC Daniel Tello from Decommissioned/Decommissioning Nuclear Facilities in Canada DISCUSSION 20

Wednesday, March 8 Session Time Or2anization S0eaker Presentation Title 8:00-8:30 EPRI Jean Smith Lessons Learned: Harvesting and Shipping of Zorita Materials 8:30- 9:00 DOE Tom Rosseel LWRS Program: Harvesting Lessons Learned 9:00 - 9:30 NRC Matthew Hiser NRC Perspective on Harvesting Experience and Lessons Learned 9:30 - 10:00 CRIEPI Taku Arai CRIEPI Research Activities with Harvested 4

Materials 10:00-10:15 BREAK 10:15 - 10:45 Energy Gerry van Zion Harvesting Experience and Lessons Solutions Noordennen Learned 10:45 - 11: 15 Dominion Sill Zipp Kewaunee Insights on Material Harvesting 11:15 -12:00 DISCUSSION 12:00-1:30 LUNCH 1:30-1:45 PNNL (for Pradeep Ramuhalli Technical Information Needed for Informed NRC)

Harvesting Decisions 1:45 - 2:30 DISCUSSION s

2:30 - 3:00 Action Items and Next Steps EPRI Sherry Bernhoft 3:00- 4:00 DOE Rich Reister Closing Thoughts NRC RobertTregoning ALL 21

Appendix Ill Harvesting Opportunities in Germany Past and current decommissioning projects of P ototype or Commercial Reactors Name I Abbrev.

Rheinsberg KKR Compact Natrium Cooled KKN Reactor Multipurpose Research R.

MZFR Obrigheim KWO Neckarwestheim 1 GKN-1 lsar-1 KKl-1 Gundremmingen-A KRB-A Greifswald 1-5 KGR 1-5 Lingen KWL WWER SNR PWR/O2O PWR PWR BWR BWR WWER BWR Power I Oecom.

MW.

started 70 1995 21 1993 57 1987 357 2008 840 2017 912 2017 250 1983 440 1995 268 1985 UC: unconditional clearance UC UC UC UC UC UC RCAKRB-11 UC UC after SE RCA: radiation controlled area, new license NRC Harvesting Workshop, RoclMHe, March 2017. Oecormisslonlng in Germany SE: safe enclosure Past and current decommissioning projects of Prototype or Commercial Reactors Name Strategy Stade KKS PWR 672 2005 UC Research Reactor J0lich AVR HTR 15 1994 UC Thorium High-THTR-HTR 308 1993 SE since 1997 Temperature-Reaktor 300 W0rgassen KWW BWR 670 1997 UC M0lheim-Karlich KMK PWR 1302 2004 UC Hot-Steam Reactor HOR HOR 25 1983 UC since 1998 Grosswelzheim N iederaichbach KKN

[)RR/DP 106 1975 UC since 1994 Test-Reactor Kahl VAK BWR 16 1988 UC since 2010 22

Shut down Commercial Re ctors

• that have no decommissioning license granted yet Name Abbrev.

Reactor type Philippsburg-1 KKP-1 BWR Grafenrheinfeld KKG PWR Biblis-A KWB-A PWR Biblis-8 KWB-8 PWR Unterweser KKU BWR Brunsbuttel KKB BWR Krummel KKK BWR

• Commercial Reactors in operation Name Abbrev.

Reactor type Gundremmingen-8 KRB-11-8 BWR Philippsburg-2 KKP-2 PWR Gundremmingen-C KRB-11-C BWR Grohnde KWG PWR Brokclorf KBR PWR Emsland KKE PWR lsar-2 KKl-2 PWR Neckarwestheim-2 GKN-2 PWR 23 frMiihNM 926 1345 1225 1300 1410 806 1402 Date of application 2013 / 2014 2014 2012 2012 2012 / 2013 2012 / 2014 2015 Anticipated date of final shutdown 1344 31.12.2017 1468 31.12.2019 1344 31.12.2021 1430 31.12.2021 1480 31.12.2021 1406 31.12.2022 1485 31.12.2022 1400 31.12.2022

From:

Sent:

To:

Subject:

Frankl, Istvan Tue, 30 May 2017 17:55:24 -0400 Hiser, Matthew RE: Workshop Summary Report Note to requester: The attachment is immediately following this email.

Attachments:

Harvesting Workshop Summary Report draft 5-26-17 (IF}.docx Thanks Matt.

This is a well-written report. Please see my attached editorial revisions and comments.

Steve From: Hiser, Matthew Sent: Friday, May 26, 2017 9:18 AM To: Purtscher, Patrick <Patrick.Purtscher@nrc.gov>; Tregoning, Robert <Robert.Tregoning@nrc.gov>;

Hull, Amy <Amy.Hull@nrc.gov>; Frankl, Istvan <lstvan.Frankl@nrc.gov>

Subject:

RE : Workshop Summary Report I have incorporated significant input from Amy and Pat on the Harvesting Workshop Summary Report.

The latest version of the report is attached.

My plan is to send this complete draft to the workshop participants for review and comment by Wednesday, May 31. Please provide any further input or comments by next Wednesday to be incorporated in the draft sent to workshop participants.

I will ask for feedback from workshop participants by the end of June with the intent to finalize this summary report by mid-July.

Please let me know if you have any questions or suggestions on how to best move this effort forward.

Thanks!

Matt

Ex-Plant Materials Harvesting Workshop Summary Report Workshop held on March 7-8, 2017 at NRC headquarters in Rockville, MD NRC staff: Matthew Hiser, Patrick Purtscher, Amy Hull, Robert Tregoning

Table of Contents Background................................................................................................................................................... l Objective and Approach............................................................................................................................... 1 Workshop Organization and Sessions.......................................................................................................... 2 Summary of Workshop Discussion............................................................................................................... 2 Session 1. Motivation for Harvesting........................................................................................................ 2 Presentation Summaries...................................................................................................................... 2 Discussion Summary............................................................................................................................. 3 Session 2. Technical Data Needs for Harvest ing....................................................................................... 3 Presentation Summaries......................................................................................................................3 Discussion Summary............................................................................................................................. 5 Session 3. Sources of Materials................................................................................................................ 6 Presentation Summaries...................................................................................................................... 6 Discussion Summary............................................................................................................................. 9 Session 4. Harvesting Experience: Lessons Learned and Practical Aspects.............................................. 9 Presentation Summaries...................................................................................................................... 9 Discussion Summary........................................................................................................................... 13 Session 5. Future Harvesting Program Planning..................................................................................... 13 Presentation Summary....................................................................................................................... 13 Discussion Summary........................................................................................................................... 13 Key Takeaways from Workshop................................................................................................................. 14 Session 1. Motivation for Harvesting...................................................................................................... 14 Session 2. Technical Data Needs for Harvest ing..................................................................................... 14 Session 3. Sources of Materials.............................................................................................................. 14 Session 4. Harvesting Experience: Lessons Learned and Practical Aspects............................................ 16 Session 5. Future Harvesting Program Planning..................................................................................... 16 Action Items and Next Steps...................................................................................................................... 16 References to Previous Harvested Materials Research.............................................................................. 17 Appendix I Workshop Participants............................................................................................................. 19 Appendix II Workshop Agenda................................................................................................................... 20 Appendix Ill Harvesting Opportunit ies in Germany.................................................................................... 22

List of Figures Figure 1 Schematic of Westinghouse ex-vessel neutron dosimetry (EVND)................................................ 5 Figure 2 Nuclear Fuels and Materials Library (NFML) Database Design............................*.......................... 7 Figure 3 Zorita Internals Research Project (ZIRP) Timeline........................................................................ 10 List of Tables Table 1 Ongoing Harvesting Programs..............................................................................*........................ 15 Table 2 Potential Future Sources for Harvesting........................................................................................ 15 iii

=

Background===

On March 7-8, 2017, the Office of Nuclear Regulatory Research of the United States Nuclear Regulatory Commission (NRC) hosted a 2-day workshop on the topic of "Ex-Plant Materials Harvesting." NRC staff worked in close coordination with staff from the U.S. Department of Energy (DOE) and the Electric Power Research Institute (EPRI) to plan and arrange the workshop.

~he decision to organize this workshop was driven by developments in the U.S. and global nuclear industry. In the U.S., there is strong interest in extending plant lifespans through subsequent license renewal (SLR) from 60 t o 80 years. Extended plant operation and SLR raise a number of technical issues that may require further research to understand aging mechanisms, which may benefit from harvesting.

Meanwhile, in recent years, a number of nuclear plants, both in the U.S. and internationally, have shut down or announced plans to shut down. Unlike in the past when there were very few plants shutting down, these new developments provide opportunities for harvesting components that were aged in representative light water reactor (LWR) environments. In a related development, economic challenges for the nuclear industry and limited government spending have limited the resources available to support new research, including harvesting programs. Given this constrained budget environment, aligning interests and leveraging with other organizations is important to allow maximum benefit and value for future research programs.I Objective and Approach The objective of the workshop was to generat e open discussion of all aspects of ex-plant materials harvesting, including:

1. Deciding whether to harvest,

2.

Planning and implementing a harvesting program,

3.

Using the harvested materials in research programs.

Through presentations and open discussion, the workshop was organized to allow for all participants t o be better informed of the benefits and challenges of harvesting as well as to identify potential areas of common interest for future harvesting programs. Workshop sessions were aligned in broad topics to cover all aspects of harvesting that.-btt~ allowed the..fef participants to drive the discussion.

To help accomplish the workshop objectives, the workshop organizers intentionally sought a diverse group of participants. There are a large number of decommissioning plants and interested researchers outside the U.S., so the organizers focused on outreach to international participants through organizationscennectiens such as the International Atomic Energy Agency (IAEA), Organization for Economic Cooperation and Development Nuclear Energy agency (OECD/NEA), and existing professional contacts. In addition, a key goal for this workshop was to capture the broader practical perspective from plant owners and decommissioning companies, which are vital to any successful harvesting program, but may sometimes be overlooked in researcher-driven discussions. Workshop participants were also diverse in terms of technical area of focus, with metal components such as the reactor pressure vessel (RPV) and internals being discussed along with concrete and electrical components. The final list of workshop participants can be found at the end of this report in Appendix I.

4 Comme nted [FIi]: Is there any Info from the related PUM abstract that can be borrowed/ added to this paragraph or other applicable section 7

Workshop Organization and Sessions The workshop was held at NRC headquarters in Rockville, MD. Due to limited space in the meeting room and the need for a limited group size for discussion, a webinar was used to allow remote observers to benefit from the workshop. Workshop sessions were organized topically with about half the time dedicated to presentations and the remaining time set aside for discussion. Presentations were solicited from participants to cover a range of perspectives and technical areas. The final workshop agenda can be found at the end of this summary report in ~ppendix II.

The workshop was organized into five sessions as follows:

Session 1. Motivation for Harvesting Session 2. Technical Data Needs for Harvesting Session 3. Sources of Materials Session 4. Harvesting Experience: Lessons Learned and Practical Aspects Session 5. Future Harvesting Program Planning Summary of Workshop Discussion The subsections below will summarize the presentations and discussion in each session and highlight the key takeaways from the session.

Session 1. Motivation for Harvesting Session 1 focused on the motivation for harvesting and why workshop participants are interested in harvesting. As shown in Appendix II with presentation t itles, speakers for this session included:

Richard Reister from DOE, Sherry Bernhoft from EPRI, Robert Tregoning from NRC, Uwe Jendrich from the Gesellschaft fur Anlagen-und Reaktorsicherheit (GRS) in Germany, and Taku Arai from the Central Research Institute of the Electric Power Industry (CRIEPI) in Japan.

Presentation Summaries DOE described the role of harvesting within the Light Water Reactor Sustainability (LWRS) Program, including the benefits and challenges associated with harvesting. Benefits include the opportunity to fill knowledge gaps where there is limited data or experience and to inform degradation models with data from actual plant components. Challenges include cost, complexity, scheduling, logistics, limited opportunities, acquiring sufficient material pedigree information, and potential negative results impacting operating plants.

EPRI discussed the role of harvesting within the context of aging management for Long-Term Operations (LTO), including their experience from past ha,rvesting programs and criteria for future harvesting. Their experience emphasized the challenges of cost, schedule, logistics, complicated contracting and acquiring material pedigree information. EPRl's criteria for harvesting focus on demonstrating value to their members by addressing a prioritized need that cannot be addressed through other means. For EPRI, a well-developed project plan that covers funding, risk management, exit ramps, and clear roles and responsibilities is essential.

5 Commented [Fl2]: Should the presentations be added under separate appendix?

N RC shared its perspective on the benefits and challenges of harvesting in regulatory research.

Harvested materials are valuable due to the representative nature of their aging conditions, which may reduce the uncertainty associated with t he applicability of the results to operating plants compared to tests with alternative aging conditions. Harvested materials may be the best option to address technical data needs identified for extended plant operation. With increasing harvesting opportunities from decommissioning plants, a proactive approach to harvesting planning can optimize benefits by identifying t he right material with the right aging conditions for the identified knowledge gap. There are sign ificant challenges associated with harvesting, including cost, schedule, and logistics, but hopefully these can be mitigated or avoided by leveraging resources with other organizations and learning from past experience.

GRS described its role as the main technical support organization in nuclear safety for the German federal government. GRS provides technical assessment and knowledge transfer for decommissioning activities, aging management, and long-term operation for German federal and interna,tional organizations.

CRIEPI discussed its view of how harvested materials and laboratory prepared materials contribute to addressing technical issues. Harvested materials provide exposure to actual plant cond it ions, but are more limited in availability and the size of the data set that can be generated. Laboratory prepared materials general involve accelerated or simulated aging conditions, but can be used to produce larger data sets and varying parameters can allow understanding of the effect on the mechanism or property of interest. Harvested materials offer fact finding of actual plant conditions as well as confirmation and verification of results from laboratory prepared specimens.

Discussion Summary The discussion following the presentations in this session focused on clearly identifying the need to be addressed by a harvesting project and the myriad cost, schedule, and logistical challenges associated with harvesting. Leveraging with other organizations to defray costs can also help improve the value of a given program, but also adds complexity as another organization may have a different set of priorities that changes the focus of the harvesting effort.

Session 2. Technical Data Needs for Harvesting Session 2 focused on discussing the technical data needs for harvesting and what specific knowledge gaps organizations are interested in addressing through harvesting. This discussion included general perspectives on how to determine when harvesting should be pursued rather than other types of research. As shown in Appendix II with prese111tation t itles, speakers for this session included:

Pradeep Ramuhalli from the Pacific Northwest National Lab (PNNL),

Matthew Hiser from NRC, Keith Leonard from Oak Ridge National Laboratory (ORNL),

Rachid Chaouadi from the Belgian Nuclear Research Centre (SCK-CEN) in Belgium, and Arzu Alpan from Westinghouse.

Presentation Summaries PNNL presented their work, under a small NRC contract, to develop a systematic approach to prioritize data needs for harvesting. PNNL proposed five primary criteria for prioritizing harvesting:

6

Unique field aspects of degradation o

For example, unusual operating experience or legacy materials (composition, etc.) that may be no longer available Ease of laboratory replication of degradation scenario (combination of material and environment) o For example, simultaneous thermal and irradiation conditions may be difficult to replicate or mechanism sensitive to dose rate may not be good for accelerated aging Applicability of harvested material?. for addressing crit ical gaps o

Prioritize harvesting for critical gaps over less essential data needs Availability of reliable in-service inspection (ISi) techniques for t he material/ component o

If inspection methods are mat ure and easy to apply to monitor and track degradation, perhaps the effort of research with harvest ed materials is not needed.

Availability of material?. for harvest ing o

The necessary materials/ components must be available to be harvested.

PNNL t hen presented t heir application of these criteria to four materials degradation issues as an example: electrical cables, cast austenitic stainless steel (CASS), reactor vessel internals, and dissimilar metal welds. Based on applying these criteria to t he examples, PNNL concluded that electrical cables, CASS, and react or internals are all higher prior ity for harvesting due to unique aspects of the degradation that are challenging to replicate in the lab. Meanwhile, dissimilar metal welds are of low priority due to the ease of replication in lab aging studies as well as the significant body of knowledge and research on the phenomena.

NRC presented a summary of data needs it is interested in pursuing through harvesting. These included RPV materials to validate fluence and attenuation models and to demonstrat e the conservatism of regulatory approaches for transition temperature prediction. Other metal components of interest for harvesting would address data gaps in irradiated stainless steels, as well as improve understanding of inspection capabilities and fatigue life calculations. Electrical components of int erest include low and medium voltage cables and other electrical components for degradation studies, and electrical enclosures and cables for fire research. Concrete components of interest include irradiated concrete, concrete undergoing alkali-aggregate reactions, post-tensioned structures, reinforcing steel, tendons, and spent fuel pool concrete to assess potential boric acid attack.

DOE/ ORNL presented their perspective on dat a needs for harvesting and its role in providing validat ion of experimental and theoretical research. DOE/ORNL performed a significant RPV harvesting program at the Zion nuclear power plant to reduce uncertainties in the Master Curve methodology, validate modeling predictions and study flux and fluence attenuation effects. The harvesting is largely complete, but t he testing program is currently underway. DOE/ OR NL also indicated interest in usi ng harvested materials to validate its models for swelling and microstructural changes of stainless steel internals under LWR irradiation conditions. Harvesting concrete components would be of interest due to lack of literature data and the mult iple dependent variables t hat may affect concrete performance. Finally, DOE/ORNL has been involved in harvesting cables from t he Crystal River and Zion plants to address cable aging as a function of material composition and environment.

SCK-CEN presented their int erest in an international cooperative program to harvest RPV materials. SCK-CEN presented their survey of the literature for past testing programs of harvested RPV materials, and 7

the limitations of t hese past program. Key limitations include a lack of archive materials, generally lower temperatures, and poor surveillance programs and dosimetry. SCK-CEN then shared some thoughts on their criteria for a new harvesting efforts, including higher fluence levels and temperatures, available archive materials and reliable information on operating history, dosimetry and surveillance program.

Other topics relevant to a new RPV harvesting effort include technical issues such as material variability and irradiation conditions as well as logistical and financial considerations.

The final presentation in Session 2 by Westinghouse focused on the need for harvesting irradiated concrete to better understand the threshold radiation level for sign ificant strength reduction. Westinghouse has installed ex-vessel neutron dosimetry (EVND) at a number of plants in the world and proposed to use these dosimetry measurements to validate fluence model calculations to better understand the uncertainty in these calculations. Figure 1 show s a schematic of the EVND setup. If DoS1metry capsules

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Support bar Dosimetry chain concrete can be harvested at one of these plants Westingt,ouse with EVND data, then irradiated concrete properties from testing can be paired with fluence data to improve research benefits.

Discussion Summary Figure 1 Schematic of Westinghouse ex-vessel neutron dosimetry (EVND)

The discussion following Session 2 presentations touched on a number of topics. EPRI shared that they developed a report related to the topics of Session 2, but more narrowly focused on pressurized water reactor (PWR) internals. MRP-320, "Testing Gap Assessment and Material Identification for PWR Internals," focuses on priorit izing opportunistic harvesting of st ainless steel reactor internals components that may be removed from service following MRP-227 inspections. The methodology and approach in this report may be relevant to the broader harvesting data needs discussion. This report is not p ublicly available, but is available to EPRI member utilities.

Workshop participants discussed the criteria proposed by PNNL in the first presentation. One additional criteria suggested by EPRI was to consider fleet-wide vs. plant-specific applicability. More broadly applicable materials would be of greater interest for harvesting than those that represent conditions at only a few plants. Another criteria suggested is the availability of material pedigree information, such as composition, processing, environmental conditions (temperature, humidity, fluence, etc.). Another suggested criteria was the ease of harvesting, which includes the concept of weighing costs vs. benefits as w ell as project risk. For example, highly irradiated internals are probably much more difficult and expensive to harvest than electrical cables or unirradiated concrete. Further discussion touched on the idea that different organizations may priorit ize t he various criteria different ly, but all will probably at least want to consider t he same set of criteria.

Another key theme from t his discussion was that a successful program should be guided by a clearly defined objective or problem statement to be addressed. This objective should be well-understood at the initiation of a program and used to guide decision-making through implementation of a harvesting 8

project. This also raises a related point or potential criteria: the timeliness of the expected research results relative to the objective. If the results are needed in the next two years, but a harvesting project will not provide results for at least five years, t hat should be a strong consideration.

Session 3. Sources of Materials Session 3 focused on discussing sources of materials for harvesting. This discussion covered previously harvested materials as well as sources for new harvesting programs from operating or decommissioning plants. Both domestic and international sources of materials were discussed in this session. As shown in Appendix II with presentation titles, speakers for this session included:

Matthew Hiser from NRC, Al Ahluwalia from EPRI, Tom Rosseel from DOE/ORNL, John Jackson from DOE/Idaho National Laboratory (INL),

Gerry van Noordennen from EnergySolutions, Arzu Alpan from Westinghouse, Uwe Jendrich from GRS, and Daniel Tello from the Canadian Nuclear Safety Commission (CNSC).

Presentation Summaries NRC presented their perspective on sources o.f materials for harvesting. First, NRC shared information on some of t he harvested materials from past research programs that may be available, including irradiated stainless steel internals, RPV materials, nickel alloy welds, neutron absorber material, a,nd electrical components. NRC then summarized the recently and planned shutdown U.S. plants, including their design, thermal out put, and years of operation, to provide participants with an idea of the potential sources from decommissioning U.S. plants. Finally, NRC shared a list of information that would be helpful to acquire from decommissioning plarnts to determine the value of components for harvesting.

This information included plant design information (component location and dimensions),

environmental conditions (temperature, fluence, humidity, stress, etc.) and operating history, material pedigree information (fabrication records), and inspection records (for interest in components with known flaws).

The next presentation from EPRI covered harvesting opportunities at decommissioning plants in Korea and Sweden. In Korea, Kori-1 is a Westinghouse 2-loop PWR (sister plant is Kewaunee) that will shut down in 2017 after 40 years of operation. Korea Hydro and Nuclear Power Central Research Institute (KHNP-CRI) is planning a comprehensive research program on long-term materials aging based on harvesting from Kori-1 and is seeking international participation in the harvesting effort. KHNP-CRl's plan is focused on metallic components, including RPV, internals, primary syst em components, steam generator materials. Harvesting is expected to occur in 2024 with testing to follow through 2030.

In Sweden, Vattenfall is currently harvesting in 2017-2018 RPV material from t he decommissioning Barseback boiling water reactor (BWR) units. This work is focused on irradiation embrittlement, including comparison of surveillance data to actual RPV properties, as well as thermal aging embrittlement. In the future, Vattenfall will be shutting down Ringhals 1 and 2 in 2020 and 2019, respectively. Ringhals 1 is a BWR and Ringhals 2 is a Westinghouse 3-loop PWR design. Of particular note, Ringhals 2 has the second oldest replaced Alloy 690 RPV head and steam generators. Other 9

(b )( 4)

(b )(4)

(b )( 4) harvesting opportunities at Ringhals include RPV material with a significant surveillance program, thermal aging effects on low alloy steel from the pressurizer, as well as concrete structures. Vattenfall is open to working with partners that are interested in joining them for harvesting at Ringhals.

The next presentation by DOE/ORNL focused on several harvesting programs that DOE's LWRS program has been involved with. DOE/ORNL has led the harvesting of components from the Zion !

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~-(~J)1l]in t he U.S. From Zion, DOE/ORNL has harvested electrical cables and components, a large RPV

..... *"'sect ion, and a significant number of records to provide information on material fabrication, in-service inspection and operating history. Cables from Zion include CROM, thermocouple, and low and medium voltage cables. DOE/ORNL indicated some t he rmocouple cables from Zion may be available for other researchers to use in collaborative studies.

(b)(1)

DOE/ORNL is also participating in efforts

'"t-o""h_a_rv_e_s'"t"'c*a'"b1'""e-s""fr_o_m_ C_ry-s-ta""I-R-iv_e_r""(""le-d""b_y_E_P_R_1'"") a_n_d_c_o_n_c-re_t_.e from the Zorita plant in Spain (led by NRC).

The next presentation by DOE/I NL described I NL's Nuclear Science User Facilities (NSUF) and the Nuclear Fuels and Materials Library (NFML). NSUF is coordinated by INL and facilitates access to nuclear research facilities around t he world, including neutron and ion irradiations, beam lines, hot cell testing, characterization and computing capabilities. NFML is a Web-based searchable database sample library that captures the information from thousands of specimens available to NSUF. NFML is designed to maximize the benefit of previously irradiated materials for future research. Researchers can propose new research projects under NSUF using specimens in NFML using DOE funding.

As seen in Figure 2, the information captured in

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Database Design NFML aligns well with t he goal of t his session to potent ially develop a database of previously harvested materials.

The next presentation by EnergySolutions offered a more practical perspective on considering sources of materials for harvesting. From t he plant owne r perspective, iR the aeESRlRlissiaRiRg 13racess there is D.QAGt-a financial incentive to support harvesting during decommissioning, therefore researchers need to absorb the costs Qffef harvesting and have a clear scope for harvesting. Flexibility in funding for harvesting activities is essential as the decommissioning process and schedule may change quickly.

EnergySolutions provided valuable perspective on the timing in the decommissioning process for harvesting different components. For instance, t he h.!arvest ing of RPV surveillance coupons should take place when the RPV internals are cut and removed. Harvesting of RPV materials is only possible from larger RPVs, as smaller RPVs are shipped intact to t he disposal facility, rather than cut into pieces. Spent fuel rack neutron absorber coupons must be harvested either before or after the dry storage campaign to remove spent fuel from the spent fuel pool. Harvesting actual spent fuel rack neutron absorber 10

material must come after the pool is completely empty. Electrical cables and other components from mild environments may be harvested at any time (once temporary power is est ablished and plant power is shut off), while t he harvesting of electrical components from high rad environments w ill depend on

!hg_timing of source:-term removal schedule&. Concrete cores are best harvested when other cores are being taken for site characterization to develop t he License Termination Plan. Highly irradiated concrete from the biological shield wall would need to come later in decommissioning after the RPV is removed.

In terms of upcoming decommissioning plants, EnergySolutions indicated that San Onofre and Vermont Yankee will be entering DECON i.!J.is 2018 and 2019, respectively. Kewaunee, Crystal River, and Fort Calhoun also may enter DECON in the next 2 years. If researchers are interested in harvesting from any of these plants, they should be reaching out to plant owners immediately to begin planning and coordination.

Westinghouse followed !!Q_their presentation in Session 2 by describing an opportunity to harvest concrete from the Mihama 1 plant in Japan, Westinghouse installed and analyzed additional neutron dosimetry in the reactor cavity for one cycle, which were used to validate the radiation transport calcu lations. Mihama was shutdown in 2015 and is in contact with Westinghouse about the possibility of extracting concrete cores from the biological shield wall. Westinghouse is seeking partners interested in joining this harvesting effort.

The next presentation by GRS covered opportunities for harvesting from German plants. Regulations in Germany require plants to either immediately dismantle or dismantle after a period of safe enclosure, which is largely consistent with options in the U.S. GRS detailed the status of German commercial reactors, which are predominantly BWR and PWR designs. Seventeen reactors are currently undergoing decommissioning, while seven more are currently shutdown and await a decommissioning license, Eight reactors are still operating with scheduled shutdown dates between 2017 and 2022. German RPVs tend to have lower fluence than U.S. designs due to a larger water gap in the downcomer region. Germany has limited experience wit h harvesting from decommissioning plants. One question that GRS will follow-up on is the "rumored" cable surveillance programs that may be used in Germany and could provide experience and lessons learned for other countries.

The final presentation in Session 3 was by CNSC on harvesting opportunities in Canada. Atomic Energy Canada Limited (AECL) has harvested seven concrete cores from the 20 megawatt electric (MWe)

Nuclear Power Demonstration Plant (NPD), which shutdown in 1988 after 25 years of operation. CNSC and AECL are also considering opportunities to harvest concrete from other decommissioned reactors in Canada such as Gentilly-2, Douglas Point, and Whiteshell Reactor l. In addition to concrete, CNSC and AECIL are currently harvesting electrical cables from the 675 MWe CANDU-6 Gentilly-2 reactor, which shutdown in 2012 after 29 years of operation. The purpose of this work is to study cable degradation from thermal aging and radiation damage and validate environmental qualification of the cables, CNSC described some of the challenges with this harvesting effort, such as working with plant owners, records, accessibility and contamination of the materials and budgeting with unexpect ed delays in harvesting.

A future harvesting opportunity is from the National Research Universal (NRU) reactor at Chalk River, which will shut down in 2018 after operating since 1957, AECL is currently taking an inventory of irradiated materials that can be harvested from NRU in decommissioning. Potential materials for 11

harvesting include metals (steels, nickel alloys, zirconium, aluminum), concret e, graphite, active equipment (pumps, etc.), graphite seals, electrical cables, and thermocouples.

Discussion Summary Following the presentations, there was some discussion of lessons learned from DO E's Zion harvesting effort. DOE worked with a former senior reactor operator at Zion to identify and acquire the appropriate records from Zion for t he components being harvested. DOE also described their flexible approach to acquiring RPV samples by sending a large chun k of mat erial (weighing ~go tons) to EnergySolut ions' facility in Tennessee, where smaller pieces (weighing ~soo pounds) were cut to send to ORNL. Most of the decontamination was performed at Zion, wit h minimal additional cleaning (as well as cladding removal) taking place at EnergySolut ions' facility.

There was also discussion of acquiring materials from sources other than commercial nuclear facilities.

DOE has considered harvesting concrete from other DOE nuclear facilities, but determined that there were compositional differences between the DOE facilities and commercial facilit ies that would make the concrete from DOE facilit ies not useful. DOE/I NL mentioned that the Advanced Test Reactor (ATR) replaces their core internals every ten years. The ATR internals are composed primarily of 347 stainless stee l and achieve very high fluence levels after ten years of service.

Another key discussion topic was the possibility of developing a database for previously harvested materials or those available for future harvesting. DOE/I NL Indicated that their NSUF sample library may be a good starting point for such a database, although any materials in t hat library should be freely available for use in the research community. CNSC, NRC, and PNNL also expressed interested in working to develop a harvesting database.

Session 4. Harvesting Experience: Lessons Learned and Practical Aspects Session 4 focused on lessons learned and practical aspects of harvesting. Presenters shared t heir experience with past harvesting programs, particularly common pitfalls to avoid and successful st rat egies to overcome them. Present ations also covered the practical aspects of harvesting from the plant owner and decommissioning company perspective. As shown in Appendix II wit h presentation titles, speakers for this session included:

Jean Smith from EPRI, Tom Rosseel from DOE/ORNL, Matthew Hiser from NRC, Taku Arai from CRIEPI, Gerry van Noordennen from EnergySolutions, and Bill Zipp from Dominion.

12

Presentation Summaries EPRI presented their experience and lessons learned from past harvesting programs, particularly harvesting reactor internals and concrete from Zorita and electrical cables from Crystal River. From the Zorita reactor internals experience, EPRI emphasized that

~i.:.~---

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encounter both material retrieval and on-site challenges, and shipping Issues. As Figure 3 Zorita Internals Research Project (ZIRP) Timeline shown in Figure 3, the Zorita Internals Research Project (ZIRP) took about 10 years to go from initial planning to final results, which included about 5 years of project planning, 2 years for material extraction (on-site logistics and shipping), and 3-4 years for testing. EPRl's experience was that decommissioning activities were the top priority and that harvesting was secondary, subject to schedule and logistical challenges based on the changing decommissioning schedule. Shipping issues were also challenging due to sending activated materials (which were classified as "waste") acros.s international borders, from the reactor in Spain to the testing facility in Sweden. Currently, further planned shipments of the Zorita materials beyond the initial program continue to be impacted by export license challenges in Sw eden. More positively, EPRI emphasized that the Zorita reactor internals materials harvesting showed excellent cooperation among many organizations and are now providing valuable technical information to numerous research projects.

Lessons learned from the Zorita concrete harvesting focused on the challenges with core sample drilling and handling contaminated concrete. Ultimat ely, an effective core drilling procedure was identified, but required some trial and error. Lessons learned from t he Crystal River cable harvesting included material concerns, t he need for on-site support, and cost. In terms of material concerns, radiation and asbestos contamination created additional challenges for harvesting. On-site support and the ability to visit the site are extremely valuable to ensure clear communication, retrieval or records for material pedigree information, and awareness of on-site developments in the decommissioning process. Cable harvesting at Crystal River was more expensive than anticipated, particularly in terms of EPRI project management time to coordinate the harvesting activities and engineering support at the plant.

DOE/ORNL presented lessons learned primarily from the experience harvesting RPV materials and electrical cables and components from the Zion plant. In terms of planning and decision-making, DOE/ORNL had several lessons learned. DOE/ORNL hosted a workshop at Zion in 2011 to discuss long-term goals and objectives, which proved very helpful in setting priorities and developing partnerships with other organizations. Partnerships were very valuable to DOE/ORNL's harvesting efforts, allowing for leveraging resources and collaboration and sharing results. There are limited opportunities for harvesting key components, so DOE/ORNL emphasized that participants should take full advantage of the opportunities that arise, understanding that t here is a necessary compromise between the materials available and their value in terms of fluence or exposure to aging conditions. Another consideration is the quant ity of material harvested, which should be sufficient for the objectives of the planned research as well as any collaborations or partnerships, but limited to control costs.

For implementing the harvesting program, DOE/ORNL found that flexibility was paramount to be able to adjust scope and plans in response to schedule changes and other developments, while remaining within cost constraints. Working with a former reactor operator was extremely valuable to benefit from 13

(b )( 4) their in-depth knowledge of all parts of the plant, in particular the records for materials pedigree information. Regular site visits and contacts were also essential to stay aware of the latest developments in the harvesting planning and decommissioning process, with t he understanding that harvesting is not the top priority for the decommissioning company, Other important considerations were hazardous materials handling, transportation, and disposal and logistics, including contracts, liability, shipping and disposal. Finally, DOE/ORNL's experience is that the total costs ofa harvesting program from planning to execution to testing are very high, so t hey should be carefully weighed against the value of the expected data to be generated.

NRC presented their experience, including benefits from previous harvesting programs, and technical and logistical lessons learned from harvesting. As an organization, NRC has extensive experience with testing harvested materials, including RPV, primary system components, reactor internals, neut ron absorbers, concrete and electrical components. NRC's experience is more limited than DOE or EPRI in terms of managing the logistics of a harvesting effort from a decommissioning plant. NRC has generally participated in a secondary role in cooperative efforts or received failed components from operating plants for research, NRC has found t hat previous harvesting efforts have been effective in reducing unnecessary conservatism, understanding in-service flaws more realistically for NOE and leak rate methodologies, as well as identifying and better understanding safety issues.

For t echnical lessons learned, NRC's perspective is t hat harvesting can provide highly representat ive aged materials for research, which may be the only practical source of such materials. Harvested materials can be effectively used to validate models or a larger data set from accelerated aging tests. It is important to understand as much as possible about t he materials and their in-service environment and how this compares with the operating fleet of reactors before committing to a specific harvesting project. For logistical lessons learned, harvesting is expensive and time-consuming, so a significant technical benefit is needed to ensure the program provides value. Leveraging resources with other organizations can help minimize costs, but can also introduce challenges for aligning priorities and interests of multiple organizations. Finally, transporting irradiated materials, particularly between countries, is challenging and t ime-consuming and should be avoided if at all possible.

CRIEPI presented t heir research experience with harvested materials as well as ongoing harvesting from the Hamaoka 1 plant. The first research program involved atom probe tomography (APT) on RPV surveillance materials. CRIEPI found a correlation between t he volume fraction of Ni-Si-Mn clusters and the change in nil-ductility temperature. In the second research project, CRIEPI characterized the weld and base materials harvested from Greifswald Unit 4 RPV with small-angle neutron scatt ering, APT, and hardness testing. In t he third research project, CRIEPI performed APT on 304L stainless steel reactor internals harvested from control rod and top guide components from 3-13 dpa. Results showed a strong increase in Ni-Si clusters with increasing fluence, but little variation in Al enriched clusters with increasing fluence.

For future work, CRIEPI is collaborating with the DOE LWRS program to investigate RPV materials harvested from Zion-===---------------' CRIEPI also presented activities

"'"""""u'nde'i'wa'v'bv Chub-~ El~~tric Power to harvest RPV and concrete samples from t he Hamaoka 1 plant.

Hamaoka 1 is a 540 MWe BWR-4 that operated for 33 years. Harvesting began in 2015 and will cont inue through 2018.

14 Commented [Fil]: Was this a VVER-440 in the former GDR?

The final two presentations of Session 4 provided the non-researcher~ perspective from a decommissioning company and plant owner. EnergySolutions, which Is decommissioning the Zion nuclear plant among other facilities, presented Q.O..the decommissioning process and t heir experience and lessons learned from harvesting at Zion. As mentioned previously, surgical harvesting Is not the top priority for decommissioning, so researchers must recognize this and coordinate close)l'. with the decommissioning company. EnergySolutions emphasized the need to gain senior management support at the plant as well as to expect that there may be staff turnover during a multi-year harvesting effort.

Changes in scope and schedule (originating from either side) can cause frustration on booth sides. Early planning, efficient contracting, and frequent site visits are important to avoid lost opportunities and achieve a successful outcome.

At Zion, EnergySolutions worked with DOE to harvest RPV materials, cables, electrical components, and spent fuel storage racks. DOE hoped to harvest a particular RPV surveillance capsule, but was unable to do so due to the inability to identify the correct capsule. There were also challenges with harvesting RPV materials. The cut line on the Unit 2 RPV was too close to the weld to be used for research; fortunately, a successful specimen was harvested from Unit 1. For cabling, the init ial plan was to harvest from 11 different locations, but ultimately, due to unforeseen challenges,-arnl poor communication and coordination, only 4 different cable locations were harvested. Harvesting the desired cable length (30 feet) also proved challenging, with only shorter sections recovered. Searches of plant records were largely effective at providing material pedigree informat ion for cables. Concrete coring was init ially planned t o take place at Zion, but not performed due to lack of research interest. The spent fuel storage rack harvesting went smoothly, which was assisted by weekend efforts when decommissioning activities were not occurring.

The next presentation from Dominion provided its perspective on harvesting from decommissioning plants, focused on the experience at Kewaunee Power Station. The top priority (beyond safety) in decommissioning is t he preservation and good stewardship of the decommissioning trust fund. Staffing is the largest drain on the trust fund, so at Kewaunee, staff was halved within a few months of shutdown and then halved again, about 16 months after permanent shutdown once offsite emergency response requirements were eliminated. Dominion described the example of harvesting the RPV surveillance capsules at this point at Kewaunee and the significant challenges that would exist. Given the reduced staffing and the current plant state (reactor coolant system drained, pumps retired, crane and radiation monitoring not maintained), it would be much more difficult than immediately after shutdown.

Kewaunee considered harvesting the RPV surveillance specimens and estimated a cost of six to seven figures based on all the activities required to enable it at this point, post-shutdown, compared to a much lower cost just after shutdown. Dominion observed that some components, such as cables or electrical components, may be available and relatively easy to harvest at almost any time during decommissioning. However, other components such as highly irradiated internals or RPV may be best harvested either shortly after shutdown when staffing and capabilities on-site are high or wait until active demolition of the reactor, which may be years or decades later.

Dominion also touched on the discussion of records for plant components. Records requirements are limited to those needed for safety. Once the plant shuts down and the range of potential safety concerns decreases, systems are downgradecl to non-safety and the associated records are no longer required to be maintained. For perspective, Kewaunee still has all its records four years since shutdown, but w ill likely not continue this much longer. Dominion closed its presentation with a broader 15

perspective on harvesting, emphasizing the need to clearly define a problem statement and understand what technical and regulatory purpose this harvesting will serve. Early planning focused on achieving the clear objective of the work including scope, schedule, budget and contact with plant is essential to a successful harvesting effort.

Discussion Summary The discussion touched on the top lessons learned from past harvesting efforts, which included defining a clear objective and purpose for harvesting, early engagement with the plant, and site coordination during harvesting.

Another suggestion was to get utility management buy-in for the harvesting project by identifying a benefit to the utility. EPRI mentioned that cable harvesting at Crystal River went much more successfully once the utility recognized the potential benefits for SLR. Similarly, when harvesting from an operating plant, one must recognize and work through the challenges the plant may encounter when restarting operations.

During discussion, the question was raised regarding how it is determined whether harvested materials are waste. The discussion concluded that in the U.S. 10 Code of Federal Regulations (CFR) 37 is the important consideration. 10 CFR 37 defines when additional security requirements are imposed, based on the quantity and activity of materials to be transported. The definition of material as waste versus research materials is not as critical in t he U.S. EnergySolutions indicated that their shipments of waste or research material could be handled in the same way in the accordance with Department of Transportation regulations, provided that the limits in 10 CFR 37 were not reached.

Session S. Future Harvesting Program Plan nlng Session 5 focused on the information needed for informed harvesting decision-making and harvesting program planning. This session featured a presentation by Pradeep Ramuhalli from PNINL, followed by a discussion period covering harvesting program planning and reflection on the 2-day workshop.

Presentation Summary PNNL presented its perspective on t he information needed for informed harvesting decision-making.

First, the purpose of the harvesting effort needs to be defined by identifying the technical knowledge gaps to be addressed. Next, a research plan should be developed demonstrating how the harvested material will be used to address the identified gaps. Finally, the appropriate source of material to address the technical gap must be identified, along with resources to support the effort and plans and timelines to perform the harvesting. The specifics of these plans depend greatly on the source of materials and must be flexible based on changing conditions on the ground.

In assessing the best source of materials, researchers should consider the material, its environment, and its condition. Material information includes fabrication information such as manufacturer, composition, and dimensions as well as information related to installation or construction, such as welding processes and parameters. Environmental information includes temperature, humidity, fluence, flux, stress (service, residual, installation), and coolant chemistry. Component condition information includes inspection history, such as identified flaws or degradation.

16

Discussion Summary The discussion in Session 5 focused on t he best practical approach to plan future harvesting programs.

There was clear agreement that this approach must begin with ident ifying t he data needs best addressed by harvesting, whether from operating or decommissioning plants. Once a specific need Is identified, the next step is to find a source to acquire the materials of interest as well as other organizations interested in participating in the harvesting effort.

Key Takeaways from Workshop Session 1. Motivation for Harvesting The clear takeaway from the discussion in Session 1 was that harvesting requires significant resources to be done successfully; therefore it is paramount to identify how the planned harvesting will clearly address a significant need to ensure the harvesting project provides strong value. In t he context of the need for data, EPRI suggested t hat the goal of harvesting to support research for operation out to 80 years should is-not ~

a f.ilkomprehensive understanding of all aspects of the-degrada,t ion, but rather a snapshot to confirm other lab results and models. This is an important point for all organizations and researchers to keep in mind before investing significant resources in harvesting.

Session 2. Technical Data Needs for Harvesting The criteria proposed by PNNL are a good starting point for prioritizing issues to address by harvesting.

Three additional important criteria would be:

Fleet-wide vs. plant-specific applicability of data, Ease of harvesting (in terms of cost and project risk), and Timeliness of the expected research results relative to the objective.

Once a potential harvesting project has reached the point of looking at different sources of materials, the availability of material pedigree information, such as composition, processing, environmental conditions (temperature, humidity, fluence, etc.) is very important to the overall value of harvesting from that particular plant.

Based on the presentations and discussion in Session 2, there appeared to be two areas where participants had broad interest in pursuing further harvesting: high fluence reactor internals and irradiated concrete. The common drivers for the interest in these issues is a lack of representative data at the fluences of interest and significant challenges with acquiring representative data, through other means. High fluence reactor internals have been addressed somewhat by ZIRP, but st ainless steel materials exposed to higher fluence levels at h igher temperatures, where void swelling may become sign ificant, could help validate DOE and EPRI models and provide further technical basis for PWR internals aging management. Irradiated concrete harvesting is currently being pursued from the Zorita reactor in Spain, with international collaboration and potential testing at the Halden Reactor Project.

Other areas with some, but less widespread, interest expressed from workshop participants for new harvesting efforts included RPV materials and electrical cables and components. SCK-CEN and NRC expressed interest in RPV harvesting, and NRC expressed interest in electrical component harvesting.

17

Session 3. Sources of Materials To capture the key takeaways from Session 3 focused on sources of materials, two tables of potential sources of materials are presented below. Table 1 covers recent or ongoing harvesting programs, while Table 2 details potential future harvesting opportunities.

Table 1 Ongoing Harvesting Proitrams Country Plant Design Size Years in Components Organization(s)

(MWe) operation Canada NPD CANDU 20 25 Concrete Gentilly-2 CANDU-6 675 29 Cables AECL Japan Hamaoka 1 BWR-4 540 33 RPV, concrete CRIEPI, Chubu Spain Zorita w 1-loop 160 37 Internals, concrete EPRI, NRC Sweden Barseback ABB-II 6,15 28 RPV Vattenfall Zion1/2 W - 4 1040 24/25 RPV, cables, DOE, EPRI, NRC loop neutron absorbers U.S.

Crystal River 3 B&W 860 36 Cables EPRI (b )(4)

Table 2 Potential Future Sources for Harvesting Country Plant Design Size Years in Potential Notes (MWe) operation Components Canada NRU Test reactor 135 61 TBD AECL; SD:

MWt 2018 Germany Numerous plants either in decommissioning or shutting down soon. See Appendix Ill.

Japan M ihama W 2-loop 320 40 Concrete

Kansai, Westinghouse RPV, internals, Korea Kori 1 W 2-loop 576 40 SGs, pressurizer, KHNP, EPRI welds, CASS, Ringhals 1 BWR 883 44 RPV, internals Vattenfall; Sweden Ringhals 2 W 3-loop 900 44 SGs, pressurizer, SD: 2020 /

concrete 2019 Kewaunee W 2-loop 566 39 TBD SD: 2013 SONGS 2/3 CE 2-looo 1070 31/30 TBD SD: 2013 Crystal River 3 B&W 860 36 TBD SD: 2013 Vermont BWR-4/Mk-1 605 42 TBD SD: 2015 U.S.

Yankee Fort Calhoun CE 2-loop 482 43 TBD SD: 2016 Palisades CE 2-loop 805 47 TBD SD: 2018 Pilgrim BWR-3/Mk-1 677 47 TBD SD: 2019 Oyster Creek BWR-2/Mk-1 619 so TBD SD: 2019 18

Indian Point w 4-loop 1020 /

48/46 TBD SD: 2021 2/3 1040 Diablo Canyon W4-loop 1138/

40 TBD SD: 2024-5 1/2 1118 Non-Advanced 250 commercial; Test Reactor Test reactor MWt so Core internals internals replaced every 10 years In addition to the potential sources of materials presented and discussed in Session 3, another takeaway was the suggestion of developing a database for previously harvested materials or those available for future harvesting. The NSUF sample library may be a good starting point for such a database, with appropriate modifications for the purposes of harvesting efforts.

Session 4. Harvesting Experience: Lessons Learned and Practical Aspects There were several important takeaways from Session 4 that were touched on in multiple presentations and the following discussions. One key takeaway is that researchers should identify a clear purpose and scope for harvest ing. Having a clear purpose for harvesting helps to guide later decisions that must be made to adjust course when t he inevitable changes in schedule or unexpected realit ies at the plant arise. A related note is that harvesting is not the top priority for decommissioning. Therefore, researchers must have clear objectives and scope for harvesting that can be communicated to the site.

This understanding should shape assumptions and interactions with the plant owner or decommissioning company as well as planning for costs and schedule.

Another takeaway was the value of strong site coordination, including site visits. Multiple presenters touched on the value of being on-site to talk to staff and see the components to be harvested. Mockups and 3-0 simulations can be valuable to ensure success of the approach or technique used to acquire the specimen. A related point is working with reactor operators at the plant. Several harvesting efforts worked with former reactor operators and benefited greatly from their experience to fi nd records or determine the best method to harvest the desired component. This is a valuable insight that could be effective in future harvesting efforts.

A third key takeaway is early engagement with the plant personnel to express interest in harvesting. This serves to make the plant aware of interest in harvesting and get their support to work w ith the harvesting process. The other important benefit of early engagement is to gain as much information as possible about the available materials and components, including the associated records and material pedigree information.

Session 5. Future Harvesting Program Planning The key takeaway in Session 5 was to gather as much information as possible in advance of committ ing to a specific harvesting project. Ideally, there would be a strong understanding that the material and its aging conditions clearly align with an identified t echnical data need before committing significant resources to a harvesting effort.

Action Items and Next Steps The following is a summary of the action items discussed at t he end of the workshop:

19

l. Sharing r,vorkshop slide~

NRC emailed attendees to ask their comfort wit h sharing their workshop slides with other organizations and received no objection from any presenters.

The presentations can be accessed here:

httos://drive.google,com/open ?id=0BS DWMLchSYSXcnoZZ0JOS0SSQU u '

2.

EPRI indicated t hat MRP-320 (Product ID: 1022866) on knowledge gaps for irradiated austenitic stainless steel for potential harvesting from MRP-227 inspections is publicly available for a fee.

3. Cable surveillance programs in Germany GRS to inquire wit h cable colleagues and share any insights.

4. Sources of materials database Potential sources of materials presented in t his workshop are summarized in Session 3 summary above and Appendix Ill below.

NRC will be reaching out t o PNNL, INL NSUF, CNSC, AECL, and any other organizations interested in database development.

5. Priorit ized data needs Suggestion to continue discussions on prioritized data needs within technical areas (RPV, internals, electrical, concrete) through existing coordination groups if possible Focus on identifying specific material/ aging conditions of interest and purpose

/ Intended outcome of harvesting Idea to survey [Env Deg 1partici pant s John Jackson (INL) is o n planning committee

6. EPRI report on spent fuel liner boric add transport through concrete NRC will contact EPRI for report if needed.

7. Harvested Materials Research Results Section of workshop summary report (below) devoted to references from harvested materials research.

References to Previous Harvested Materials Research This section of the workshop summary addresses a question that was raised during t he discussion at t he workshop regarding what t he outcome or benefit of past harvesting efforts have been. Below is a list of references ~o research results generated from testing of harvested materials:

J.R. Hawthorne and A.L. Hiser, Experimental Assessments af Gundremmingen RPV Archive Material far Fluence Rate Effects Studies, NUREG/CR-5201 (MEA-2286), U.S. Nuclear Regulatory Commission, October 1988.

O.K. Chopra, and W.J. Shack, Mechanical Properties of Thermally Aged Cast Stainless Steels from Shippingport Reactor Components, NUREG/CR-6275 (ANL-94/37), U.S. Nuclear Regulatory Commission, April 1995.

20 Commented [Fl4]: As commented above, should the slides be Included In this report under new appendix?

Commented [FIS]: Conference? Please spell out the name.

! Commented [F16]: Please number the 11st of references.

G. J. Schuster, S. R. Doctor, S.L. Crawford, and A. F. Pardini, Characterization of Flaws in U.S. Reactor Pressure Vessels: Density and Distribution of Flaw Indications in the Shoreham Vessel, NUREG/CR-6471 Volume 3, U.S. Nuclear Regulatory Commission, November 1999.

G. J. Schust er, S. R. Doctor, A.F. Pardini, and S.L. Crawford, Characterization of Flaws in U.S. Reactor Pressure Vessels: Validation of Flaw Density and Distribution in the Weld Metal of the PVRUF Vessel, NUREG/CR-6471 Volume 2, U.S. Nuclear Regulatory Commission, August 2000.

D.E. McCabe, et al. Evaluation of WF-70 Weld Metal From the Midland Unit 1 Reactor Vessel, NUREG/CR-5736 (ORNL/TM-13748), U.S. Nuclear Regulatory Commission, November 2000.

B. Alexandreanu, O.K. Chopra, and W.J. Shack, Crock Growth Rates In a PWR Environment of Nickel Alloys from the Davis-Besse and V.C. Summer Power Plants, NUREG/CR-6921 (ANL-05/55), U.S. Nuclear Regulatory Commission, November 2006.

S.E. Cumblidge, et al. Nondestructive and Destructive Examination Studies on Removed-from-Service Control Rad Drive Mechanism Penetrations, N UREG/CR-6996, U.S. Nuclear Regulatory Commission, July 2009.

S.E. Cumblidge, et al. Evaluation of Ultrasonic Time-of-Flight Diffraction Data for Selected Control Rod Drive Nozzles from Davis Besse Nuclear Power Plant, PNNL-19362, Pacific Northwest National Laboratory, April 2011.

S.L. Crawford, et al. Ultrasonic Phased Array Assessment of the Interference Fit and Leak Path of the North Anno Unit 2 Control Rod Drive Mechanism Nozzle 63 with Destructive Validation, NUREG/CR-7142 (PNNL-21547), U.S. Nuclear Regulatory Commission, August 2012.

21

Appendix I Workshop Participants Name Or11anization Email Taku Arai CRIEPI a rait@crieoi.denken.or.io Sadao Higuchi CRIEPI higuchi@criei:1i.denken.or.j [1 Japan Kazunobu Sakamoto JNRA kazunobu sakamoto@nsr.go,i11 Yasuhiro Chimi JAEA chimi,\\/asuhiro@jaea.go.j[!

Uwe Jendrich GRS Uwe.Jendrichors.de Europe Rachid Chaouadi SCK-CEN rachid.chaouadi@sckcen.be Guy Roussel Bel V gU\\/.rDUSSel@Belv.be Daniel Tello CNSC daniel.tellocanada.ca Canada Desire Ndomba CNSC desire.ndomba@canada.ca Karen Huynh AECL khu','nh@aecl.ca Gerrv van Noordennen Enen;iv Solutions QovannoordennenenerQvsolutions.com us Bill Zipp Dominion william.f.zii:1i:1@dom.com Industry Mark Richter NEI mar@nei.org Arzu Alpan Westinghouse al11anfa@westinghouse.com Sherrv Bernhoft EPRI sbernhoft@eori.com Robin Dyle EPRI rd\\/le@e11ri.com EPRI Jean Smith EPRI jmsmith@ei:1ri.com Al Ahluwalia EPRI kahluwal@ei:1ri.com Tom Rosseel ORNL rosseeltm@ornl.2ov Rich Reister DOE Richard.Reister@nuclear.energ.,,.gov Keith Leonard ORNL leonardk@ornl.gov DOE Mikhail A. Sokolov ORNL sokolovm@ornl.gov John Wagner INL john.wagner@inl.gov John Jackson INL john.jackson@inl.gov Pradeep Ramuhalli PNNL Pradeei:1.Ramuhalli@11nnl.gov Pat Purtscher NRC Patrick. Pu rt sch e r@n re. l!OV Rob Tregoning NRC Robert.Tregoning@nrc.gov Matt Hiser NRC Matthew.Hiser@nrc.gov Mita Sircar NRC Madhumita.Sircar@nrc.gov Tom Koshy NRC Thomas.Kosh'{@nrc.gov NRC Jeff Poehler NRC Jeffre'{.Poehler@nrc.gov Allen Hiser NRC Allen.Hiser@nrc.gov Angela Buford NRC Angela.Buford@nrc.gov Mark Kirk NRC Mark.Kirk@nrc.gov Amy Hull NRC Am'{.Hull@nrc.gov Pete Ricardella NRC/ACRS Priccardella@Structint.com 22

Appendix II Workshop Agenda Tuesday, March 7 Session Time Oreanization Soeaker Presentation Title Intro 8:00 NRC Michael Weber Welcome and Introduction to Workshop Robert Tregoning DOE Rich Reister DOE Perspectives on Material Harvestinl!

EPRI Sherry Bernhoft EPRI Perspective on Harvesting Projects 8:15-8:45 NRC Robert Tregoning NRC Perspective on Motivation for Harvesting 1

GRS Uwe Jendrich Role of GRS in Decommissioning and LTO CRIEPI Taku Arai CRIEPI Motivations for Harvested Material 8:45-9:45 DISCUSSION 9:45-10:00 BREAK 10:00-PNNL (for NRC)

Pradeep Ramuhalli Data Needs Best Addressed By Harvesting 10:20 10:20-NRC Matthew Hiser High-Priority Data Needs for Harvesting 10:30 10:30-DOE Keith Leonard LWRS Program Perspective on the Technical 10:55 Needs for Harvestine 2

10:55 -

Review of past RPV sampling test programs 11:20 SCK-CEN Rach id Chaouadi and perspective for long term operation 11:20-Westinghouse Arzu Alpan Importance of Harvesting to Evaluate 11:45 Radiation Effects on Concrete Prooerties 11:45 -

DISCUSSION 12:30 12:30- 2:00 LUNCH 2:00 - 2:10 NRC Matthew Hiser Sources of Materials: Past NRC Harvest ing and U.S. Decommissioning Plants 2:10-2:35 EPRI Ai Ahluwalia Harvesting Plans for Materials Aging Degradation Research in Korea and Sweden 2:35-2:50 DOE/ORNL Tom Rosseel Materials Harvested bv the LWRS Program 2:50-3:00 DOE/INL John Jackson NSUF Material Sample Library 3:00-3:15 Energy Solutions Gerry van Zion Material Harvesting Program Noordennen 3

Potential Harvesting of Concrete from M ihama 3:15 - 3:30 Westinghouse Arzu Alpan Unit 1 3:30- 3:45 BREAK 3:45-4:00 GRS Uwe Jendrich Plants in Decommissioning in Germany Evaluating Structures, Systems & Components 4:00 - 4:15 CNSC Daniel Tello from Decommissioned/Decommissioning Nuclear Facilities in Canada 4:15-5:00 DISCUSSION 23

Wednesday, March 8 Session Time Or2anization S0eaker Presentation Title 8:00-8:30 EPRI Jean Smith Lessons Learned: Harvesting and Shipping of Zorita Materials 8:30- 9:00 DOE Tom Rosseel LWRS Program: Harvesting Lessons Learned 9:00 - 9:30 NRC Matthew Hiser NRC Perspective on Harvesting Experience and Lessons Learned 9:30 - 10:00 CRIEPI Taku Arai CRIEPI Research Activities with Harvested 4

Materials 10:00-10:15 BREAK 10:15 - 10:45 Energy Gerry van Zion Harvesting Experience and Lessons Solutions Noordennen Learned 10:45 - 11: 15 Dominion Sill Zipp Kewaunee Insights on Material Harvesting 11:15 -12:00 DISCUSSION 12:00-1:30 LUNCH 1:30-1:45 PNNL (for Pradeep Ramuhalli Technical Information Needed for Informed NRC)

Harvesting Decisions 1:45 - 2:30 DISCUSSION s

2:30 - 3:00 Action Items and Next Steps EPRI Sherry Bernhoft 3:00- 4:00 DOE Rich Reister Closing Thoughts NRC RobertTregoning ALL 24

Appendix Ill Harvesting Opportunities in Germany Past and current decommissioning projects of P ototype or Commercial Reactors Name I Abbrev.

Rheinsberg KKR Compact Natrium Cooled KKN Reactor Multipurpose Research R.

MZFR Obrigheim KWO Neckarwestheim 1 GKN-1 lsar-1 KKl-1 Gundremmingen-A KRB-A Greifswald 1-5 KGR 1-5 Lingen KWL WWER SNR PWR/O20 PWR PWR BWR BWR WWER BWR Power I Oecom.

MW.

started 70 1995 21 1993 57 1987 357 2008 840 2017 912 2017 250 1983 440 1995 268 1985 UC: unconditional clearance UC UC UC UC UC UC RCAKRB-11 UC UC after SE RCA: radiation controlled area, new license NRC Harvesting Workshop, RoclMHe, March 2017. Oecormisslonlng in Germany SE: safe enclosure Past and current decommissioning projects of Prototype or Commercial Reactors Name Strategy Stade KKS PWR 672 2005 UC Research Reactor J0lich AVR HTR 15 1994 UC Thorium High-THTR-HTR 308 1993 SE since 1997 Temperature-Reaktor 300 W0rgassen KWW BWR 670 1997 UC M0lheim-Karlich KMK PWR 1302 2004 UC Hot-Steam Reactor HOR HOR 25 1983 UC since 1998 Grosswelzheim N iederaichbach KKN IDRRIOp 106 1975 UC since 1994 Test-Reactor Kahl VAK BWR 16 1988 UC since 2010 25

Shut down Commercial Re ctors

• that have no decommissioning license granted yet Name Abbrev.

Reactor type Philippsburg-1 KKP-1 BWR Grafenrheinfeld KKG PWR Biblis-A KWB-A PWR Biblis-8 KWB-8 PWR Unterweser KKU BWR Brunsbuttel KKB BWR Krummel KKK BWR

• Commercial Reactors in operation Name Abbrev.

Reactor type Gundremmingen-8 KRB-11-8 BWR Philippsburg-2 KKP-2 PWR Gundremmingen-C KRB-11-C BWR Grohnde KWG PWR Brokclorf KBR PWR Emsland KKE PWR lsar-2 KKl-2 PWR Neckarwestheim-2 GKN-2 PWR 26 frMiihNM 926 1345 1225 1300 1410 806 1402 Date of application 2013 / 2014 2014 2012 2012 2012 / 2013 2012 / 2014 2015 Anticipated date of final shutdown 1344 31.12.2017 1468 31.12.2019 1344 31.12.2021 1430 31.12.2021 1480 31.12.2021 1406 31.12.2022 1485 31.12.2022 1400 31.12.2022

From:

Sent:

To:

Subject:

Attachments:

Hiser, Matthew Fri, 26 May 2017 13:18:00 +0000 Note to requester: The attachment is immediately following this email.

Purtscher, Patrick;Tregoning, Robert;Hull, Amy;Frankl, Istvan RE: Workshop Summary Report Harvesting Workshop Summary Report draft 5-26-17.docx I have incorporated significant input from Amy and Pat on the Harvesting Workshop Summary Report.

The latest version of the report is attached.

My plan is to send this complete draft to the workshop participants for review and comment by Wednesday, May 31. Please provide any further input or comments by next Wednesday to be incorporated in the draft sent to workshop participants.

I will ask for feedback from workshop participants by the end of June with the intent to finalize this summary report by mid-July.

Please let me know if you have any questions or suggestions on how to best move this effort forward.

Thanks!

Matt

Ex-Plant Materials Harvesting Workshop Summary Report Workshop held on March 7-8, 2017 at NRC headquarters in Rockville, MD NRC staff: Matthew Hiser, Patrick Purtscher, Amy Hull, Robert Tregoning

Table of Contents Background................................................................................................................................................... 1 Objective and Approach............................................................................................................................... 1 Workshop Organization and Sessions.......................................................................................................... 2 Summary of Workshop Discussion............................................................................................................... 2 Session 1. Motivation for Harvesting........................................................................................................ 2 Presentation Summaries...................................................................................................................... 2 Discussion Summary............................................................................................................................. 3 Session 2. Technical Data Needs for Harvesting....................................................................................... 3 Presentation Summaries...................................................................................................................... 3 Discussion Summary............................................................................................................................. 5 Session 3. Sources of Materials................................................................................................................ 6 Presentation Summaries...................................................................................................................... 6 Discussion Summary............................................................................................................................. 9 Session 4. Harvesting Experience: Lessons Learned and Practical Aspects.............................................. 9 Presentation Summaries...................................................................................................................... 9 Discussion Summary........................................................................................................................... 13 Session 5. Future Harvesting Program Planning..................................................................................... 13 Presentation Summary....................................................................................................................... 13 Discussion Summary........................................................................................................................... 13 Key Takeaways from Workshop................................................................................................................. 14 Session 1. Motivation for Harvesting...................................................................................................... 14 Session 2. Technical Data Needs for Harvesting..................................................................................... 14 Session 3. Sources of Materials.............................................................................................................. 14 Session 4. Harvesting Experience: Lessons Learned and Practical Aspects............................................ 16 Session 5. Future Harvesting Program Planning..................................................................................... 16 Action Items and Next Steps...................................................................................................................... 16 References to Previous Harvested Materials Research.............................................................................. 17 Appendix I Workshop Participants............................................................................................................. 19 Appendix II Workshop Agenda................................................................................................................... 20 Appendix Ill Harvesting Opportunities in Germany.................................................................................... 22 ii

List of Figures Figure 1 Schematic of Westinghouse ex-vessel neutron dosimetry (EVND)................................................ 5 Figure 2 Nuclear Fuels and Materials Library (NFML) Database Design....................................................... 7 Figure 3 Zorita Internals Research Project (ZIRP) Timeline........................................................................ 10 List of Tables Table 1 Ongoing Harvesting Programs....................................................................................................... 15 Table 2 Potential Future Sources for Harvesting........................................................................................ 15 iii

=

Background===

On March 7-8, 2017, the Office of Nuclear Regulatory Research of the United States Nuclear Regulatory Commission (NRC) hosted a 2-day workshop on the topic of "Ex-Plant Materials Harvesting." NRC staff worked in close coordination with staff from the U.S. Department of Energy (DOE) and the Electric Power Research Institute (EPRI) to plan and arrange the workshop.

The decision to organize this workshop was driven by developments in the U.S. and global nuclear industry. In the U.S., there is strong interest in extending plant lifespans through subsequent license renewal (SLR) from 60 to 80 years. Extended plant operation and SLR raise a number of technical issues that may require further research to understand aging mechanisms, which may benefit from harvesting.

Meanwhile, in recent years, a number of nuclear plants, both in the U.S. and internationally, have shut down or announced plans to shut down. Unlike in the past when there were very few plants shutting down, these new developments provide opportunities for harvesting components that were aged in representative light water reactor (LWR) environments. In a related development, economic challenges for the nuclear industry and limited government spending have limited the resources available to support new research, including harvesting programs. Given this constrained budget environment, aligning interests and leveraging with other organizations is important to allow maximum benefit and value for future research programs.

Objective and Approach The objective of the workshop was to generate open discussion of all aspects of ex-plant materials harvesting, including:

1.

Deciding whether to harvest,

2.

Planning and implementing a harvesting program,

3.

Using the harvested materials in research programs.

Through presentations and open discussion, the workshop was organized to allow for all participants to be better informed of the benefits and challenges of harvesting as well as to identify potential areas of common interest for future harvesting programs. Workshop sessions were aligned in broad topics to cover all aspects of harvesting, but allow for participants to drive the discussion.

To help accomplish the workshop objectives, the workshop organizers intentionally sought a diverse group of participants. There are a large number of decommissioning plants and interested researchers outside the U.S., so the organizers focused on outreach to international participants through connections such as the International Atomic Energy Agency (IAEA), Organization for Economic Cooperation and Development Nuclear Energy agency (OECD/NEA), and existing professional contacts.

In addition, a key goal for this workshop was to capture the broader practical perspective from plant owners and decommissioning companies, which are vital to any successful harvesting program, but may sometimes be overlooked in researcher-driven discussions. Workshop participants were also diverse in terms of technical area of focus, with metal components such as the reactor pressure vessel (RPV) and internals being discussed along with concrete and electrical components. The final list of workshop participants can be found at the end of this report in Appendix I.

4

Workshop Organization and Sessions The workshop was held at NRC headquarters in Rockville, MD. Due to limited space in the meeting room and the need for a limited group size for discussion, a webinar was used to allow remote observers to benefit from the workshop. Workshop sessions were organized topically with about half the time dedicated to presentations and the remaining time set aside for discussion. Presentations were solicited from participants to cover a range of perspectives and technical areas. The final workshop agenda can be found at the end of this summary report in Appendix II.

The workshop was organized into five sessions as follows:

Session 1. Motivation for Harvesting Session 2. Technical Data Needs for Harvesting Session 3. Sources of Materials Session 4. Harvesting Experience: Lessons Learned and Practical Aspects Session 5. Future Harvesting Program Planning Summary of Workshop Discussion The subsections below will summarize the presentations and discussion in each session and highlight the key takeaways from the session.

Session 1. Motivation for Harvesting Session 1 focused on the motivation for harvesting and why workshop participants are interested in harvesting. As shown in Appendix II with presentation titles, speakers for this session included:

Richard Reister from DOE, Sherry Bernhoft from EPRI, Robert Tregoning from NRC, Uwe Jendrich from the Gesellschaft fur Anlagen-und Reaktorsicherheit (GRS) in Germany, and Taku Arai from the Central Research Institute of the Electric Power Industry (CRIEPI) in Japan.

Presentation Summaries DOE described the role of harvesting within the Light Water Reactor Sustainability (LWRS) Program, including the benefits and challenges associated with harvesting. Benefits include the opportunity to fill knowledge gaps where there is limited data or experience and to inform degradation models with data from actual plant components. Challenges include cost, complexity, scheduling, logistics, limited opportunities, acquiring sufficient material pedigree information, and potential negative resullts impacting operating plants.

EPRI discussed the role of harvesting within the context of aging management for Long-Term Operations (LTO), including their experience from past harvesting programs and criteria for future harvesting. Their experience emphasized the challenges of cost, schedule, logistics, complicated contracting and acquiring material pedigree information. EPRl's criteria for harvesting focus on demonstrating value to their members by addressing a prioritized need that cannot be addressed through other means. For EPRI, a well-developed project plan that covers funding, risk management, exit ramps, and clear roles and responsibilities is essential.

5

NRC shared its perspective on the benefits and challenges of harvesting in regulatory research.

Harvested materials are valuable due to the representative nature of their aging conditions, which may reduce the uncertainty associated with the applicability of the result s to operating plants compared to tests with alternative aging conditions. Harvested materials may be the best option to address technical data needs identified for extended plant operation. With increasing harvesting opportunities from decommissioning plants, a proactive approach to harvesting planning can optimize benefits by identifying the right material with the right aging conditions for the identified knowledge gap. There are significant challenges associated with harvesting, including cost, schedule, and logistics, but hopefully these can be mitigated or avoided by leveraging resources with other organizations and learning from past experience.

GRS described its role as the main technical support organization in nuclear safety for the German federal government. GRS provides technical assessment and knowledge transfer for decommissioning activities, aging management, and long-term operation for German federal and international organizations.

CRIEPI discussed its view of how harvested materials and laboratory prepared materials contribute to addressing technical issues. Harvested materials provide exposure to actual plant conditions, but are more limited in availability and the size of the data set that can be generated. Laboratory prepared materials general involve accelerated or simulated aging conditions, but can be used to produce larger data sets and varying parameters can allow understanding of the effect on the mechanism or property of interest. Harvested materials offer fact finding of actual plant conditions as well as confirmation and verification of results from laboratory prepared specimens.

Discussion Summary The discussion following the presentations in this session focused on clearly identifying the need to be addressed by a harvesting project and the myriad cost, scheduile, and logistical challenges associated with harvesting. Leveraging with other organizations to defray costs can also help improve the value of a given program, but also adds complexity as another organization may have a different set of priorities that changes the focus of the harvesting effort.

Session 2. Technical Data Needs for Harvesting Session 2 focused on discussing the technical data needs for harvesting and what specific knowledge gaps organizations are interested in addressing through harvesting. This discussion included general perspectives on how to determine when harvesting should be pursued rather than other types of research. As shown in Appendix II with presentation titles, speakers for this session included:

Pradeep Ramuhalli from the Pacific Northwest National Lab (PNNL),

Matthew Hiser from NRC, Keith Leonard from Oak Ridge National Laboratory (ORNL),

Rachid Chaouadi from the Belgian Nuclear Research Centre (SCK-CEN) in Belgium, and Arzu Alpan from Westinghouse.

Presentation Summaries PNNL presented their work, under a small NRC contract, to develop a systematic approach to prioritize data needs for harvesting. PNNL proposed five primary criteria for prioritizing harvesting:

6

Unique field aspects of degradation o

For example, unusual operating experience or legacy materials (composition, etc.) that may be no longer available Ease of laboratory replication of degradation scenario (combination of material and environment) o For example, simultaneous thermal and irradiation conditions may be difficult to replicate or mechanism sensitive to dose rate may not be good for accelerated aging Applicability of harvested material for addressing critical gaps o

Prioritize harvesting for critical gaps over less essential data needs Availability of reliable in-service inspection (ISi) techniques for the material/ component o

If inspection methods are mature and easy to apply to monitor and track degradation, perhaps the effort of research with harvested materials is not needed.

Availability of material for harvesting o

The necessary materials/ components must be available to be harvested.

PNNL then presented their application of these criteria to four materials degradation issues as an example: electrical cables, cast austenitic stainless steel (CASS), reactor vessel internals, and dissimilar metal welds. Based on applying these criteria to the examples, PNNL concluded that electrical cables, CASS, and reactor internals are all higher priority for harvesting due to unique aspects of the degradation that are challenging to replicate in the lab. Meanwhile, dissimilar metal welds are of low priority due to the ease of replication in lab aging studies as well as the significant body of knowledge and research on the phenomena.

NRC presented a summary of data needs it is interested in pursuing through harvesting. These included RPV materials to validate fluence and attenuation models and to demonstrate the conservatism of regulatory approaches for transition temperature prediction. Other metal components of interest for harvesting would address data gaps in irradiated stainless steels, as well as improve understanding of inspection capabilities and fatigue life calculations. Electrical components of interest include low and medium voltage cables and other electrical components for degradation studies, and electrical enclosures and cables for fire research. Concrete components of interest include irradiated concrete, concrete undergoing alkali-aggregate reactions, post-tensioned structures, reinforcing steel, tendons, and spent fuel pool concrete to assess potential boric acid attack.

DOE/ORNL presented their perspective on data needs for harvesting and its role in providing validation of experimental and theoretical research. DOE/ORNL performed a significant RPV harvesting program at the Zion nuclear power plant to reduce uncertainties in the Master Curve methodology, validate modeling predictions and study flux and fluence attenuation effects. The harvesting is largely complete, but the testing program is currently underway. DOE/ORNL also indicated interest in using harvested materials to validate its models for swelling and microstructural changes of stainless steel internals under LWR irradiation conditions. Harvesting concrete components would be of interest due to lack of literature data and the multiple dependent variables that may affect concrete performance. Finally, DOE/ORNL has been involved in harvesting cables from the Crystal River and Zion plants to address cable aging as a function of material composition and environment.

SCK-CEN presented their interest in an international cooperative program to harvest RPV materials. SCK-CEN presented their survey of the literature for past testing programs of harvested RPV materials, and 7

the limitations of these past program. Key limitations include a lack of archive materials, generally lower temperatures, and poor surveillance programs and dosimetry. SCK-CEN then shared some thoughts on their criteria for a new harvesting efforts, including higher fluence levels and temperatures, available archive materials and reliable information on operating history, dosimetry and surveillance program.

Other topics relevant to a new RPV harvesting effort include technical issues such as material variability and irradiation conditions as well as logistical and financial considerations.

The final presentation in Session 2 by Westinghouse focused on the need for harvesting irradiated concrete to better understand the threshold radiation level for significant strength reduction. Westinghouse has installed ex-vessel neutron dosimetry (EVND) at a number of plants in the world and proposed to use these dosimetry measurements to validate fluence model calculations to better understand the uncertainty in these calculations. Figure 1 shows a schematic of the EVND setup. If Dosimetry capsules Dosimetry chain concrete can be harvested at one of these plants Westinghouse IJ 0 with EVND data, then irradiated concrete properties from testing can be paired with fluence data to improve research benefits.

Discussion Summary Figure 1 Schematic of Westinghouse ex-vessel neut ron dosimetry (EVND)

The discussion following Session 2 presentations touched on a number of topics. EPRI shared that they developed a report related to the topics of Session 2, but more narrowly focused on pressurized water reactor (PWR) internals. MRP-320, "Testing Gap Assessment and Material Identification for PWR Internals," focuses on prioritizing opportunistic harvesting of stainless steel reactor internals components that may be remo-ved from service following MRP-227 inspections. The methodology and approach in this report may be relevant to the broader harvesting data needs discussion. This report is not publicly available, but is available to EPRI member utilities.

Workshop participants discussed the criteria proposed by PNNL in the first presentation. One additional criteria suggested by EPRI was to consider fleet-wide vs. plant-specific applicability. More broadly applicable materials would be of greater interest for harvesting than those that represent conditions at only a few plants. Another criteria suggested is the availability of material pedigree information, such as composition, processing, environmental conditions (temperature, humidity, fluence, etc.). Another suggested criteria was the ease of harvesting, which includes the concept of weighing costs vs. benefits as well as project risk. For example, highly irradiated internals are probably much more difficult and expensive to harvest than electrical cables or unirradiated concrete. Further discussion touched on the idea that different organizations may prioritize the various criteria differently, but all will probably at least want to consider the same set of criteria.

Another key theme from this discussion was that a successful program should be guided by a clearly defined objective or problem statement to be addressed. This objective should be well-understood at the initiation of a program and used to guide decision-making through implement ation of a harvesting 8

project. This also raises a related point or potential criteria: the timeliness of the expected research results relative to the objective. If the results are needed in the next two years, but a harvesting project will not provide results for at least five years, that should be a strong consideration.

Session 3. Sources of Materials Session 3 focused on discussing sources of materials for harvesting. This discussion covered previously harvested materials as well as sources for new harvesting programs from operating or decommissioning plants. Both domestic and international sources of materials were discussed in this session. As shown in Appendix II with presentation titles, speakers for this session included:

Matthew Hiser from NRC, Al Ahluwalia from EPRI, Tom Rosseel from DOE/ORNL, John Jackson from DOE/Idaho National Laboratory (INL),

Gerry van Noordennen from EnergySolutions, Arzu Alpan from Westinghouse, Uwe Jendrich from GRS, and Daniel Tello from the Canadian Nuclear Safety Commission (CNSC).

Presentation Summaries NRC presented their perspective on sources of materials for harvesting. First, NRC shared some of the harvested materials from past research programs that may be available, including irradiated stainless steel internals, RPV materials, nickel alloy welds, neutron absorber material, and electrical components.

NRC then summarized the recently and planned shutdown U.S. plants, including their design, thermal output, and years of operation, to provide participants with an idea of the potential sources from decommissioning U.S. plants. Finally, NRC shared a list of information that would be helpful to acquire from decommissioning plants to determine the value of components for harvesting. This information included plant design information (component location and dimensions), environmental conditions (temperature, fluence, humidity, stress, etc.) and operating history, material pedigree information (fabrication records), and inspection records (for interest in components with known flaws).

The next presentation from EPRI covered harvesting opportunities at decommissioning plants in Korea and Sweden. In Korea, Kori-1 is a Westinghouse 2-loop PWR (sister plant is Kewaunee) that wiill shut down in 2017 after 40 years of operation. Korea Hydro and Nuclear Power Central Research Institute (KHNP-CRI) is planning a comprehensive research program on long-term materials aging based on harvesting from Kori-1 and is seeking international participation in the harvesting effort. KHNP-CRl's plan is focused on metallic components, including RPV, internals, primary system components, steam generator materials. Harvesting is expected to occur in 2024 with testing to follow through 2030.

In Sweden, Vattenfall is currently harvesting in 2017-2018 RPV material from the decommissioning Barseback boiling water reactor (BWR) units. This work is focused on irradiation embrittleme11t, including comparison of surveillance data to actual RPV properties, as well as thermal aging embrittlement. In the future, Vattenfall will be shutting down Ringhals 1 and 2 in 2020 and 2019, respectively. Ringhals 1 is a BWR and Ringhals 2 is a Westinghouse 3-loop PWR design. Of particular note, Ringhals 2 has the second oldest replaced Alloy 690 RPV head and steam generators. Other harvesting opportunities at Ringhals include RPV material with a significant surveillance program, 9

(b )(4)

(b )( 4) thermal aging effects on low alloy steel from the pressurizer, as well as concrete structures. Vattenfall is open to working with partners that are interested in joining them for harvesting at Ringhals.

The next presentation by DOE/ORNL focused on several harvesting programs that DOE's LWRS program has been involved with. DOE/ORNL has led the harvesting of components from the Zion I Jtl)(~)

pJar:itB in the U.S. From Zion, DOE/ORNL has harvested electrical cables and components, a large RPV section, and a significant number of records to provide information on material fabrication, in-service inspection and operating history. Cables from Zion include CROM, thermocouple, and low and medium voltage cables. DOE/ORNL indicated some thermocouple cables from Zion may be available for other researchers to use in collaborative studies.

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The next presentation by DOE/I NL described IN L's Nuclear Science User Facilities (NSUF) and the Nuclear Fuels and Materials Library (NFML). NSUF is coordinated by INL and facilitates access to nuclear research facilities around the world, including neutron and ion irradliations, beamlines, hot cell testing, characterization and computing capabilities. NFML is a Web-based searchable database sample library that captures the information from thousands of specimens available to NSUF. NFML is designed to maximize the benefit of previously irradiated materials for future research. Researchers can propose new research projects under NSUF using specimens in NFML using DOE funding.

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Database Design NFML aligns well with the goal of this session to potentially develop a database of previously harvested materials.

The next presentation by EnergySolutions offered a more practical perspective on considering sources of materials for harvesting. From the plant owner perspective, in the decommissioning process there is not a financial incentive to support harvesting, therefore researchers need to absorb costs for harvesting and have a clear scope for harvesting. Flexibility in funding for harvesting activities is essential as the decommissioning process and schedule may change quickly.

EnergySolutions provided valuable perspective on the timing in the decommissioning process for harvesting different components. Harvesting RPV surveillance coupons should take place when the RPV internals are cut and removed. Harvesting RPV materials is only possible from larger RPVs, as smaller RPVs are shipped intact to the disposal facility, rather than cut into pieces. Spent fuel rack neutron absorber coupons must be harvested either before or after dry storage campaign to remove spent fuel from the spent fuel pool. Harvesting actual spent fuel rack neutron absorber material must come after the pool is completely empty. Elect rical cables and other components from mild environments may be 10

harvested at any time (once temporary power is established and plant power is shut off), while electrical components from high rad environments will depend on timing of source term removal schedule.

Concrete cores are best harvested when other cores are being taken for site characterization to develop the License Termination Plan. Highly irradiated concrete from !biological shield wall would need to come later in decommissioning after RPV is removed.

In terms of upcoming decommissioning plants, EnergySolutions indicated that San Onofre and Vermont Yankee will be entering DECON is 2018 and 2019, respectively. Kewaunee, Crystal River, and Fort Calhoun also may enter DECON in next 2 years. If researchers are interested in harvesting from any of these plants, they should be reaching out to plant owners immediately to begin planning and coordination.

Westinghouse followed their presentation in Session 2 by describing an opportunity to harvest concrete from the Mihama 1 plant in Japan. Westinghouse installed and analyzed additional neutron dosimetry in the reactor cavity for one cycle, which were used to validate the radiation transport calculations.

Mihama was shutdown in 2015 and is in contact with Westinghouse about the possibility of extracting concrete cores from the biological shield wall. Westinghouse is seeking partners interested in joining this harvesting effort.

The next presentation by GRS covered opportunities for harvesting from German plants. Regulations in Germany require plants to either immediately dismantle or dismantle after a period of safe enclosure, which is largely consistent with options in the U.S. GRS detailed the status of German commercial reactors, which are predominantly BWR and PWR designs. Seventeen reactors are currently undergoing decommissioning, while seven more are currently shutdown and await a decommissioning license. Eight reactors are still operating with scheduled shutdown dates between 2017 and 2022. German RPVs tend to have lower fluence than U.S. designs due to a larger water gap in the downcomer region. Germany has limited experience with harvesting from decommissioning plants. One question that GRS will follow-up on is the "rumored" cable surveillance programs that may be used in Germany and could provide experience and lessons learned for other countries.

The final presentation in Session 3 was by CNSC on harvesting opportunities in Canada. Atomic Energy Canada Limited (AECL) has harvested seven concrete cores from the 20 megawatt electric (MWe)

Nuclear Power Demonstration Plant (NPD), which shutdown in 1988 after 25 years of operation. CNSC and AECL are also considering opportunities to harvest concrete from other decommissioned reactors in Canada such as Gentilly-2, Douglas Point, and Whiteshell Reactor 1. In addition to concrete, CNSC and AECL are currently harvesting electrical cables from the 675 MWe CANDU-6 Gentilly-2 reactor, which shutdown in 2012 after 29 years of operation. The purpose of this work is to study cable degradation from thermal aging and radiation damage and validate environmental qualification of the cables. CNSC described some of the challenges with this harvesting effort, such as working with plant owners, records, accessibility and contamination of the materials and budgeting with unexpected delays in harvesting.

A future harvesting opportunity is from the National Research Universal (NRU) reactor at Chalk River, which will shut down in 2018 after operating since 1957. AECL is currently taking an inventory of irradiated materials that can be harvested from NRU in decommissioning. Potential materials for harvesting include metals (steels, nickel alloys, zirconium, aluminum), concrete, graphite, active equipment (pumps, etc.), graphite seals, electrical cables, and thermocouples.

11

Discussion Summary Following the presentations, there was some discussion of lessons learned from DOE's Zion harvesting effort. DOE worked with a former senior reactor operator at Ziion to identify and acquire the appropriate records from Zion for the components being harvested. DOE also described their flexible approach to acquiring RPV samples by sending a large chunk of material (weighing ~go tons) to EnergySolutions' facility in Tennessee, where smaller pieces (weighing ~soo pounds) were cut to send to ORNL. Most of the decontamination was performed at Zion, with minimal additional cleaning (as well as cladding removal) taking place at EnergySolutions' facility.

There was also discussion of acquiring materials from sources other than commercial nuclear facilities.

DOE has considered harvesting concrete from other DOE nuclear facilities, but determined that there were compositional differences between the DOE facilities and commercial facilities t hat would make the concrete from DOE facilities not useful. DOE/I NL mentioned that the Advanced Test Reactor (ATR) replaces their core internals every ten years. The ATR internals are composed primarily of 347 stainless steel and achieve very high fluence levels after ten years of service.

Another key discussion topic was the possibility of developing a database for previously harvested materials or those available for future harvesting. DOE/I NL indicated that their NSUF sample library may be a good starting point for such a database, although any materials in that library should be freely available for use in the research community. CNSC, NRC, and PNNL also expressed interested in working to develop a harvesting database.

Session 4. Harvesting Experience: Lessons Learned and Practical Aspects Session 4 focused on lessons learned and practical aspects of harvesting. Presenters shared their experience with past harvesting programs, particularly common pitfalls to avoid and successful strategies to overcome them. Presentations also covered the practical aspects of harvesting from the plant owner and decommissioning company perspective. As shown in Appendix II with presentation titles, speakers for this session included:

Jean Smith from EPRI, Tom Rosseel from DOE/ORNL, Matthew Hiser from NRC, Taku Arai from CRIEPI, Gerry van Noordennen from EnergySolutions, and Bill Zipp from Dominion.

12

Presentation Summaries EPRI presented their experience and lessons learned from past harvesting programs, particularly harvesting reactor internals and concrete from Zorita and electrical cables from Crystal River. From the Zorita reactor internals experience, EPRI emphasized that harvesting projects take significant time, encounter both material retrieval and on-2007 P~t lnctptlon

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I 2011 site challenges, and shipping issues. As Figure 3 Zorita Internals Research Project (ZIRP) Timeline shown in Figure 3, the Zorita Internals Research Project (ZIRP) took about 10 years to go from initial planning to final results, which included about 5 years of project planning, 2 years for material 2017

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extraction (on-site logistics and shipping), and 3-4 years for testing. EPRl's experience was that decommissioning activities were the top priority and that harvesting was secondary, subject to schedule and logistical challenges based on the changing decommissioning schedule. Shipping issues were also challenging due to sending activated materials (which were classified as "waste") across international borders, from the reactor in Spain to the testing facility in Sweden. Currently, further planned shipments of the Zorita materials beyond the initial program continue to be impacted by export license challenges in Sweden. More positively, EPRI emphasized that the Zorita reactor internals materials harvesting showed excellent cooperation among many organizations and are now providing valuable technical information to numerous research projects.

Lessons learned from the Zorita concrete harvesting focused on the challenges with core sample drilling and handling contaminated concrete. Ultimately, an effective core drilling procedure was identified, but required some trial and error. Lessons learned from the Crysta1I River cable harvesting included material concerns, the need for on-site support, and cost. In terms of material concerns, radiation and asbestos contamination created additional challenges for harvesting. On-site support and the ability to visit the site are extremely valuable to ensure clear communication, retrieval or records for material pedigree information, and awareness of on-site developments in the decommissioning process. Cable harvesting at Crystal River was more expensive than anticipated, particularly in terms of EPRI project management time to coordinate the harvesting activities and engineering support at the plant.

DOE/ORNL presented lessons learned primarily from the experience harvesting RPV materials and electrical cables and components from the Zion plant. In terms of planning and decision-making, DOE/ORNL had several lessons learned. DOE/ORNL hosted a workshop at Zion in 2011 to discuss long-term goals and objectives, which proved very helpful in setting priorities and developing partnerships with other organizations. Partnerships were very valuable to DOE/ORN L's harvesting efforts, allowing for leveraging resources and collaboration and sharing results. There are limited opportunities for harvesting key components, so DOE/ORNL emphasized that participants should take full advantage of the opportunities that arise, understanding that there is a necessary compromise between the materials available and their value in terms of fluence or exposure to aging conditions. Another consideration is the quantity of material harvested, which should be sufficient for the objectives of the planned research as well as any collaborations or partnerships, but limited to control costs.

For implementing the harvesting program, DOE/ORNL found that flexibility was paramount to be able to adjust scope and plans in response to schedule changes and other developments, while remaiining within cost constraints. Working with a former reactor operator was extremely valuable to benefit from 13

their in-depth knowledge of all parts of the plant, in particular the records for materials pedigree information. Regular site visits and contacts were also essential to stay aware of the latest developments in the harvesting planning and decommissioning process, with the understanding that harvesting is not the top priority for the decommissioning company. Other important considerations were hazardous materials handling, transportation, and disposal and logistics, including contracts, liability, shipping and disposal. Finally, DOE/ORN L's experience is that the total costs of a harvesting program from planning to execution to testing are very high, so they should be carefully weighed against the value of the expected data to be generated.

NRC presented their experience, including benefits from previous harvesting programs, and technical and logistical lessons learned from harvesting. As an organization, NRC has extensive experience with testing harvested materials, including RPV, primary system components, reactor internals, neutron absorbers, concrete and electrical components. NRC's experience is more limited than DOE or EPRI in terms of managing the logistics of a harvesting effort from a decommissioning plant. NRC has generally participated in a secondary role in cooperative efforts or received failed components from operating plants for research. NRC has found that previous harvesting efforts have been effective in reducing unnecessary conservatism, understanding in-service flaws more realistically for NOE and leak rate methodologies, as well as identifying and better understanding safety issues.

For technical lessons learned, NRC's perspective is that harvesting can provide highly representative aged materials for research, which may be the only practical source of such materials. Harvested materials can be effectively used to validate models or a larger data set from accelerated aging tests. It is important to understand as much as possible about the materials and their in-service environment and how this compares with the operating fleet of reactors before committing to a specific harvesting project. For logistical lessons learned, harvesting is expensive and time-consuming, so a significant technical benefit is needed to ensure t he program provides value. Leveraging resources with other organizations can help minimize costs, but can also introduce challenges for aligning priorities and interests of multiple organizations. Finally, transporting irradiated materials, particularly between countries, is challenging and time-consuming and should be avoided if at all possible.

CRIEPI presented their research experience with harvested materials as well as ongoing harvesting from the Hamaoka 1 plant. The first research program involved atom probe tomography (APT) on RPV surveillance materials. CRIEPI found a correlation between the volume fraction of Ni-Si-Mn clusters and the change in nil-ductility temperature. In the second research project, CRIEPI characterized tlhe weld and base materials harvested from Greifswald Unit 4 RPV with small-angle neutron scattering, APT, and hardness testing. In the third research project, CRIEPI performed APT on 304L stainless steel reactor internals harvested from control rod and top guide components from 3-13 dpa. Results showed a strong increase in Ni-Si clusters with increasing fluence, but little variation in Al enriched clusters with increasing fluence.

For future work, CRIEPI is collaborating with the DOE LWRS program to investigate RPV materials (b)(4) harvested..fromZio~

! CRIEPI also presented activities underway by Chubu Electric Power to harvest RPV and concrete samples from the Hamaoka 1 plant.

Hamaoka 1 is a 540 MWe BWR-4 that operated for 33 years. Hlarvesting began in 2015 and will continue through 2018.

14

The final two presentations of Session 4 provided the non-researcher perspective from a decommissioning company and plant owner. EnergySolutions, which is decommissioning the Zion nuclear plant among other facilities, presented the decommissioning process and their experience and lessons learned from harvesting at Zion. As mentioned previously, surgical harvesting is not the top priority for decommissioning, so researchers must recognize this and coordinate close with the decommissioning company. EnergySolutions emphasized the need to gain senior management support at the plant as well as to expect that there may be staff turnover during a multi-year harvesting effort.

Changes in scope and schedule (originating from either side) can cause frustration on both sides. Early planning, efficient contracting, and frequent site visits are important to avoid lost opportunities and achieve a successful outcome.

At Zion, EnergySolutions worked with DOE to harvest RPV materials, cables, electrical components, and spent fuel storage racks. DOE hoped to harvest a particular RPV surveillance capsule, but was unable to due to the inability to identify the correct capsule. There were also challenges with harvesting RPV materials. The cut line on the Unit 2 RPV was too close to the weld to be used for research; fortunately, a successful specimen was harvested from Unit 1. For cabling, the initial plan was to harvest from 11 different locations, but ultimately due to unforeseen challenges and poor communication and coordination, only 4 different cable locations were harvested. Harvesting the desired cable length (30 feet) also proved challenging, with only shorter sections recovered. Searches of plant records were largely effective at providing material pedigree information for cables. Concrete coring was initially planned to take place at Zion, but not performed due to lack of research interest. The spent fuel storage rack harvesting went smoothly, which was assisted by weekend efforts when decommissioning activities were not occurring.

The next presentation from Dominion provided its perspective on harvesting from decommissioning plants, focused on the experience at Kewaunee Power Station. The top priority (beyond safety) in decommissioning is the preservation and good stewardship of the decommissioning trust fund. Staffing is the largest drain on the trust fund, so at Kewaunee, staff was halved within a few months of shutdown and then halved again, about 16 months after permanent shutdown once offsite emergency response requirements were eliminated. Dominion described the example of harvesting the RPV surveillance capsules at this point at Kewaunee and the significant challenges that would exist. Given the reduced staffing and the current plant state (reactor coolant system drained, pumps retired, crane and radiation monitoring not maintained), it would be much more difficult than immediately after shutdown.

Kewaunee considered harvesting the RPV surveillance specimens and estimated a cost of six to seven figures based on all the activities required to enable it at this point, post-shutdown, compared to a much lower cost just after shutdown. Dominion observed that some components, such as cables or electrical components, may be available and relatively easy to harvest at almost any time during decommissioning. However, other components such as highly irradiated internals or RPV may be best harvested either shortly after shutdown when staffing and capabilities on-site are high or wait until active demolition of the reactor, which may be years or decades later.

Dominion also touched on the discussion of records for plant components. Records requirements are limited to those needed for safety. Once the plant shuts down and the range of potential safety concerns decreases, systems are downgraded to non-safety and the associated records are no longer required to be maintained. For perspective, Kewaunee still has all its records four years since shutdown, but will likely not continue this much longer. Dominion closed its presentation with a broader 15

perspective on harvesting, emphasizing the need to clearly define a problem statement and understand what technical and regulatory purpose this harvesting will serve. Early planning focused on achieving the clear objective of the work incliuding scope, schedule, budget and contact with plant is essential to a successful harvesting effort.

Discussion Summary The discussion touched on the top lessons learned from past harvesting efforts, which included defining a clear objective and purpose for harvesting, early engagement with the plant, and site coordination during harvesting.

Another suggestion was to get utility management buy-in for the harvesting project by identifying a benefit to the utility. EPRI mentioned that cable harvesting at Crystal River went much more successfully once the utility recognized the potential benefits for SLR. Similarly, when harvesting from an operating plant, one must recognize and work through the challenges the plant may encounter when restarting operations.

During discussion, the question was raised regarding how it is determined whether harvested materials are waste. The discussion concluded that in the U.S. 10 Code of Federal Regulations (CFR) 37 is the important consideration. 10 CFR 37 defines when additional security requirements are imposed, based on the quantity and activity of materials to be transported. The definition of material as waste versus research materials is not as critical in the U.S. EnergySolutions indicated that their shipments of waste or research material could be handled in the same way in the accordance with Department of Transportation regulations, provided that the limits in 10 CFR 37 were not reached.

Session 5. Future Harvesting Program Planning Session 5 focused on the information needed for informed harvesting decision-making and harvesting program planning. This session featured a presentation by Pradeep Ramuhalli from PNNL, followed by a discussion period covering harvesting program planning and reflection on the 2-day workshop.

Presentation Summary PNNL presented its perspective on the information needed for informed harvesting decision-making.

First, the purpose of the harvesting effort needs to be defined by identifying the technical knowledge gaps to be addressed. Next, a research plan should be developed demonstrating how the harvested material will be used to address the identified gaps. Finally, the appropriate source of material to address the technical gap must be identified, along with resources to support the effort and plans and timelines to perform the harvesting. The specifics of these plans depend greatly on the source of materials and must be flexible based on changing conditions on the ground.

In assessing the best source of materials, researchers should consider the material, its environment, and its condition. Material information includes fabrication information such as manufacturer, composition, and dimensions as well as information related to installation or construction, such as welding processes and parameters. Environmental information includes temperature, humidity, fluence, flux, stress (service, residual, installation), and coolant chemistry. Component condition information includes inspection history, such as identified flaws or degradation.

16

Discussion Summary The discussion in Session 5 focused on the best practical approach to plan future harvesting programs.

There was clear agreement tha1t this approach must begin with identifying the data needs best addressed by harvesting, whether from operating or decommissioning plants. Once a specific need is identified, the next step is to find a source to acquire the materials of interest as well as other organizations interested in participating in the harvesting effort.

Key Takeaways from Workshop Session 1. Motivation for Harvesting The clear takeaway from the discussion in Session 1 was that harvesting requires significant resources to be done successfully; therefore it is paramount to identify how the planned harvesting will clearly address a significant need to ensure the harvesting project provides strong value. In the context of need for data, EPRI suggested the goal of harvesting to support research for operation out to 80 years is not a full comprehensive understanding of all aspects of the degradation, but rather a snapshot to confirm other lab results and models. This is an important point for all organizations and researchers to keep in mind before investing significant resources in harvesting.

Session 2. Technical Data Needs for Harvesting The criteria proposed by PNNL are a good starting point for prioritizing issues to address by harvesting.

Three additional important criteria would be:

Fleet-wide vs. plant-specific applicability of data, Ease of harvesting (in terms of cost and project risk), and Timeliness of the expected research results relative to the objective.

Once a potential harvesting project has reached the point of looking at different sources of materials, the availability of material pedigree information, such as composition, processing, environmental conditions (temperature, humidity, fluence, etc.) is very important to the overall value of harvesting from that particular plant.

Based on the presentations and discussion in Session 2, there appeared to be two areas where participants had broad interest in pursuing further harvesting: high fluence reactor internals and irradiated concrete. The common drivers for the interest in these issues is a lack of representative data at the fluences of interest and significant challenges with acquiring representative data through other means. High fluence reactor internals have been addressed somewhat by ZIRP, but stainless steel materials exposed to higher flu1ence levels at higher temperatures, where void swelling may b,ecome significant, could help validate DOE and EPRI models and provide further technical basis for PWR internals aging management. Irradiated concrete harvesting is currently being pursued from the Zorita reactor in Spain, with international collaboration and potential testing at the Halden Reactor Project.

Other areas with some, but less widespread, interest expressed from workshop participants for new harvesting efforts included RPV materials and electrical cables and components. SCK-CEN and NRC expressed interest in RPV harvesting, and NRC expressed interest in electrical component harvesting.

17

Session 3. Sources of Materials To capture the key takeaways from Session 3 focused on sources of materials, two tables of potential sources of materials are presented below. Table 1 covers recent or ongoing harvesting programs, while Table 2 details potential future harvesting opportunities.

Table 1 Ongoing Harvesting Pr-ograms Country Plant Design Size Years in Components Organization(s)

(MWe) operation Canada NPD CANDU 20 25 Concrete AECL Gentilly-2 CANDU-6 675 29 Cables Japan Hamaoka 1 IBWR-4 540 33 RPV, concrete CRIEPI, Chubu Spain Zorita W 1-loop 160 37 Internals, concrete EPRI, NRC Sweden Barseback ABB-II 615 28 RPV Vattenfall Zion1/2 W - 4 1040 24/25 RPV, cables, DOE, EPRI, NRC loop neutron absorbers U.S.

Crystal River 3 B&W 860 36 Cables EPRI (b )(4)

Table 2 Potential Future Sources for Harvesting Country Plant Design Size Years in Potential Notes (MWe) operation Components Canada NRU Test reactor 135 61 TBD AECL; SD:

MWt 2018 Germany Numerous plants either in decommissioning or shutting down soon. See Appendix Ill.

Japan Mihama W 2-loop 320 40 Concrete Kans.ai, Westinghouse RPV, internals, Korea Kori 1 W 2-loop 576 40 SGs, pressurizer, KHNP, EPRI welds, CASS, Ringhals 1 BWR 883 44 RPV, internals Vattenfall; Sweden Ringhals 2 W 3-loop 900 44 SGs, pressurizer, SD: 2020 /

concrete 2019 Kewaunee W 2-loop 566 39 TBD SD: 2013 SONGS 2/3 CE 2-loop 1070 31/30 TBD SD: 2013 Crystal River 3 B&W 860 36 TBD SD: 2013 Vermont BWR-4/Mk-1 605 42 TBD SD:2015 U.S.

Yankee Fort Calhoun CE 2-loop 482 43 TBD SD:2016 Palisades CE 2-loop 805 47 TBD SD:2018 Pilgrim BWR-3/Mk-1 677 47 TBD SD:2019 Oyster Creek BWR-2/Mk-1 619 so TBD SD: 2019 18

Indian Point W 4-loop 1020/

48/46 TBD SD:2021 2/3 1040 Diablo Canyon W 4-loop 1138/

40 TBD SD: 2024-5 1/2 1118 Non-Advanced 250 commercial; Test Reactor Test reactor MWt 50 Core internals internals replaced every 10 years In addition to the potential sources of materials presented and discussed in Session 3, another takeaway was the suggestion of developing a database for previously harvested materials or those available for future harvesting. The NSUF sample library may be a good starting point for such a database, with appropriate modifications for the purposes of harvesting efforts.

Session 4. Harvesting Experience: Lessons Learned and Practical Aspects There were several important takeaways from Session 4 that were touched on in multiple presentations and the following discussions. One key takeaway is that researchers should identify a clear purpose and scope for harvesting. Having a clear purpose for harvesting hellps to guide later decisions that must be made to adjust course when the inevitable changes in schedule or unexpected realities at the plant arise. A related note is that harvesting is not the top priority for decommissioning. Therefore, researchers must have clear objectives and scope for harvesting that can be communicated to the site.

This understanding should shape assumptions and interactions with the plant owner or decommissioning company as well as planning for costs and schedule.

Another takeaway was the value of strong site coordination, including site visits. Multiple presenters touched on the value of being on-site to talk to staff and see the components to be harvested. Mock ups and 3-D simulations can be valuable to ensure success of the approach or technique used to acquire the specimen. A related point is working with reactor operators at the plant. Several harvesting efforts worked with former reactor operators and benefited greatly from their experience to find records or determine the best method to harvest the desired component. This is a valuable insight that could be effective in future harvesting efforts.

A third key takeaway is early engagement with the plant personnel to express interest in harvesting. This serves to make the plant aware of interest in harvesting and get their support to work with the harvesting process. The other important benefit of early engagement is to gain as much information as possible about the available materials and components, includling the associated records and material pedigree information.

Session 5. Future Harvesting Program Planning The key takeaway in Session 5 was to gather as much information as possible in advance of committing to a specific harvesting project. Ideally, there would be a strong understanding that the material and its aging conditions clearly align with an identified technical data need before committing significant resources to a harvesting effort.

Action Items and Next Steps The following is a summary of the action items discussed at the end of the workshop:

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1. Sharing workshop slides NRC emailed attendees to ask their comfort with sharing their workshop slides with other organizations and received no objection from any presenters.

The presentations can be accessed here:

https://drive.google.com/open?id=0BSDWMLchSYSXcnpZZ0JOS0SSQUU.

2.

EPRI indicated that MRP-320 (Product ID: 1022866) on knowledge gaps for irradiated austenitic stainless steel for potential harvesting from MRP-227 inspections is publicly available for a fee.

3.

Cable surveillance programs in Germany GRS to inquire with cable colleagues and share any insights.

4.

Sources of materials database Potential sources of materials presented in this workshop are summarized in Session 3 summary above and Appendix Ill below.

NRC will be reaching out to PNNL, INL NSUF, CNSC, AECL, and any other organizations interested in database development.

5.

Prioritized data needs Suggestion to continue discussions on prioritized data needs within technical areas (RPV, internals, electrical, concrete) through existing coordination groups if possible Focus on identifying specific material/ aging conditions of interest and purpose

/ intended outcome of harvesting Idea to survey Env Deg participants John Jackson (INL) is on planning committee

6.

EPRI report on spent fuel liner boric acid transport through concrete NRC will contact EPRI for report if needed.

7.

Harvested Materials Research Results Section of workshop summary report (below) devoted to references from harvested materials research.

References to Previous Harvested Materials Research This section of the workshop summary addresses a question that was raised during the discussion at the workshop regarding what the outcome or benefit of past harvesting efforts have been. Below is a list of references to research results generated from testing of harvested materials:

J.R. Hawthorne and A.L. Hiser, Experimental Assessments of Gundremmingen RPV Archive Material for Fluence Rate Effects Studies, NUREG/CR-5201 (MEA-2286), U.S. Nuclear Regulatory Commission, October 1988.

O.K. Chopra, and W.J. Shack, Mechanical Properties of Thermally Aged Cast Stainless Steels from Shippingport Reactor Components, NUREG/CR-6275 (ANL-94/37), U.S. Nuclear Regulatory Commission, April 1995.

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G. J. Schuster, S. R. Doctor, S.L. Crawford, and A. F. Pardini, Characterization of Flaws in U.S. Reactor Pressure Vessels: Density and Distribution of Flaw Indications in the Shoreham Vessel, NUREG/CR-6471 Volume 3, U.S. Nuclear Regulatory Commission, November 1999.

G. J. Schuster, S. R. Doctor, A.F. Pardini, and S.L. Crawford, Characterization of Flaws in U.S. Reactor Pressure Vessels: Validation of Flaw Density and Distribution in the Weld Metal of the PVRUF Vessel, NUREG/CR-6471 Volume 2, U.S. Nuclear Regulatory Commission, August 2000.

D.E. McCabe, et al. Evaluation of WF-70 Weld Metal From the Midland Unit 1 Reactor Vessel, NUREG/CR-5736 (ORNL/TM-13748), U.S. Nuclear Regulatory Commission, November 2000.

B. Alexandreanu, O.K. Chopra, and W.J. Shack, Crack Growth Rates in a PWR Environment of Nickel Alloys from the Davis-Besse and V.C. Summer Power Plants, NUREG/CR-6921 (ANL-05/55), U.S. Nuclear Regulatory Commission, November 2006.

S.E. Cumblidge, et al. Nondestructive and Destructive Examination Studies on Removed-from-Service Control Rod Drive Mechanism Penetrations, NUREG/CR-6996, IJ.S. Nuclear Regulatory Commission, July 2009.

S.E. Cumblidge, et al. Evaluation of Ultrasonic Time-of-Flight Diffraction Data for Selected Control Rod Drive Nozzles from Davis Besse Nuclear Power Plant, PNNL-19362, Pacific Northwest National Laboratory, April 2011.

S.L. Crawford, et al. Ultrasonic Phased Array Assessment of the Interference Fit and Leak Path of the North Anna Unit 2 Control Rod Drive Mechanism Nozzle 63 with Destructive Validation, NUREG/CR-7142 (PNNL-21547), U.S. Nuclear Regulatory Commission, August 2012.

21

Appendix I Workshop Participants Name Organization Email Taku Arai CRIEPI arait@crieoi.denken.or.io Sadao Higuchi CRIEPI higuchi@crieQi. den ken.or. j 12 Japan Kazunobu Sakamoto JNRA kazunobu sakamoto@nsr.go.ji:1 Yasuhiro Chimi JAEA chimi.yasuhiro@jaea.go.ji:1 Uwe Jendrich GRS Uwe.Jendrich {1i) e:rs.de Europe Rachid Chaouadi SCK-CEN rachid.chaouadi@sckcen.be Guy Roussel BelV guy.roussel@Belv.be Daniel Tello CNSC daniel.tello(a)canada.ca Canada Desire Ndomba CNSC desire.ndomba@canada.ca Karen Huynh AECL kh uynh@aecl.ca Gerrv van Noordennen Enere:v Solutions

!!Van noordennen (a)enere:vsolution s.com us Bill Zipp Dominion william.f.zi1212@dom.com industry Mark Richter NEI mar@nei.org Arzu Alpan Westinghouse al12anfa@westinghouse.com Sherry Bernhoft EPRI sbern hoft@epri.com Robin Dyle EPRI rdyle@e12ri.com EPRI Jean Smith EPRI jmsmith@e12ri.com Al Ahluwalia EPRI kahluwal@e12ri.com Tom Rosseel ORNL rosseeltm(a)ornl.e:ov Rich Reister DOE Richard.Reister@nuclear.energy.gov Keith Leonard ORNL leonardk@ornl.gov DOE Mikhail A. Sokolov ORNL sokolovm@ornl.gov John Wagner INL john.wagner@inl.gov John Jackson INL john.jackson@inl.gov Pradeep Ramuhalli PNNL Pradee12.Ramuhalli@12nnl.gov Pat Purtscher NRC Patrick.Purtscher@nrc.gov Rob Tregoning NRC Robert.Tregoning@nrc.gov Matt Hiser NRC Matthew.Hiser@nrc.gov Mita Sircar NRC Madhumita.Sircar@nrc.gov Tom Koshy NRC Thomas.Koshy@nrc.gov NRC Jeff Poehler NRC Jeffrey.Poehler@nrc.gov Allen Hiser NRC Allen.Hiser@nrc.gov Angela Buford NRC Anigela.Buford@nrc.gov Mark Kirk NRC Mark.Kirk@nrc.gov Amy Hull NRC Amy.Hull@nrc.gov Pete Ricardella NRC/ACRS Pri cca rdel la@Structint.com 22

Appendix II Workshop Agenda Tuesday, March 7 Session Time Organization Speaker Presentation Title Michael Weber Welcome and Introduction to Workshop Intro 8:00 NRC Robert Tregoning DOE Rich Reister DOE Perspectives on Material Harvesting EPRI Sherry Bernhoft EPRI Perspective on Harvesting Projects 8:15-8:45 NRC Robert Tregoning NRC Perspective on Motivation for Harvesting 1

GRS Uwe Jendrich Role of GRS in Decommissioning and LTO CRIEPI Taku Arai CRIEPI Motivations for Harvested Material 8:45-9:45 DISCUSSION 9:45-10:00 BREAK 10:00-PNNL (for NRC)

Pradeep Ramuhalli Data Needs Best Addressed By Harvesting 10:20 10:20-NRC Matthew Hiser High-Priority Data Needs for Harvesting 10:30 10:30 -

DOE Keith Leonard LWRS Program Perspective on the Technical 10:55 Needs for Harvesting 2

10:55-Review of past RPV sampling test programs 11:20 SCK-CEN Rachid Chaouadi and perspective for long term operation 11:20-Westinghouse Arzu Alpan Importance of Harvesting to Evaluate 11:45 Radiation Effects on Concrete Properties 11:45-DISCUSSION 12:30 12:30- 2:00 LUNCH 2:00 - 2:10 NRC Matthew Hiser Sources of Materials: Past NRC Harvesting and U.S. Decommissioning Plants 2:10 - 2:35 EPRI Al Ahluwalia Harvesting Plans for Materials Aging Degradation Research in Korea and Sweden 2:35-2:50 DOE/ORNL Tom Rosseel Materials Harvested by the LWRS Program 2:50- 3:00 DOE/I NL John Jackson NSUF Material Sample Library 3:00- 3:15 Energy Solutions Gerry van Zion Material Harvesting Program Noordennen 3

Potential Harvesting of Concret,e from Mihama 3:15-3:30 Westinghouse Arzu Alpan Unit 1 3:30- 3:45 BREAK 3:45 -4:00 GRS Uwe Jendrich Plants in Decommissioning in Germany Evaluating Structures, Systems & Components 4:00-4:15 CNSC Daniel Tello from Decommissioned/Decommissioning Nuclear Facilities in Canada 4:15 - 5:00 DISCUSSION 23

Wednesday, March 8 Session Time Ori?anization Speaker Presentation Title 8:00-8:30 EPRI Jean Smith Lessons Learned: Harvesting and Shipping of Zorita Materials 8:30-9:00 DOE Tom Rosseel LWRS Program: Harvesting Lessons Learned 9:00 - 9:30 NRC Matthew Hiser NRC Perspective on Harvesting Experience and Lessons Learned 9:30 -10:00 CRIEPI Taku Arai CRIEPI Research Activities with Harvested 4

Materials 10:00 - 10:15 BREAK 10:15 - 10:45 Energy Gerry van Zion Harvesting Experience and Lessons Solutions Noordennen Learned 10:45 - 11:15 Dominion Bill Zipp Kewaunee Insights on Material Harvesting 11:15 - 12:00 DISCUSSION 12:00-1:30 LUNCH 1:30 - 1:45 PNNL (for Pradeep Ramuhalli Technical Information Needed for Informed NRC)

Harvesting Decisions 1:45-2:30 DISCUSSION 5

2:30 - 3:00 Action Items and Next Steps EPRI Sherry Bernhoft DOE Rich Reister Closing Thoughts 3:00 - 4:00 NRC Robert Tregoning ALL 24

Appendix Ill Harvesting Opportunities in Germany

• Past and current decommissioning projects of Prototype or Commercial Reactors Name Reactor type --

Strategy Rheinsberg KKR WWER 70 1995 UC Compact Natrium Cooled KKN SNR 21 1993 UC Reactor Multipurpose Research R.

MZFR PWR/O20 57 1987 UC Obrigheim KWO PWR 357 2008 UC Neckarwestheim 1 GKN-1 PWR 840 2017 UC lsar-1 KKl-1 BWR 912 2017 UC Gundremmingen-A KRB-A BWR 250 1983 RCA KRB-11 Greifswald 1-5 KGR 1-5 WWER 440 1995 UC Lingen KWL BWR 268 1985 UC after SE UC: unconditional clearance RCA: radiation controlled area, new license NRC Harvesting Workshop, Rockville, March 2017, Decommissioning In Germany SE: safe enclosure 4

• Past and current decommissioning projects of ? ototype or Commercial Reactors Name Stade Research Reactor Julich Thorium High-Temperature-Reaktor Wurgassen Mulheim-Karlich Hot-Steam Reactor Grosswelzheim N iederaichbach Test-Reactor Kahl KKS AVR THTR-300 KWW KMK HOR KKN VAK Reactor type PWR HTR HTR BWR PWR HOR ORR/O2O BWR 25 Strategy 672 2005 UC 15 1994 UC 308 1993 SE since 1997 670 1997 UC 1302 2004 UC 25 1983 UC since 1998 106 1975 UC since 1994 16 1988 UC since 2010

Shut down Cor1r1erc*a1 ~Qactors

• that have no decommissioning license granted yet Name Abbrev.

Reactor type PowerMWe Philippsburg-1 KKP-1 BWR 926 Grafenrheinfeld KKG PWR 1345 Biblis-A KWB-A PWR 1225 Biblis-B KWB-B PWR 1300 Unterweser KKU BWR 1410 BrunsbUttel KKB BWR 806 Krummel KKK BWR 1402

• Commercial Reacto In operation Name Abbrev.

Reactor type Power MWe Gundremmingen-B KRB-11-B BWR 1344 Philippsburg-2 KKP-2 PWR 1468 Gundremmingen-C KRB-11-C BWR 1344 Grohnde KWG PWR 1430 Brokdorf KBR PWR 1480 Emsland KKE PWR 1406 lsar-2 KKl-2 PWR 1485 Neckarwestheim-2 GKN-2 PWR 1400 26 Date of application 2013 / 2014 2014 2012 2012 2012 / 2013 2012 / 2014 2015 Anticipated date of final shutdown 31.12.2017 31.12.2019 31.12.2021 31.12.2021 31.12.2021 31.12.2022 31.12.2022 31.12.2022

From:

Hiser, Matthew Sent:

Tue, 16 May 2017 14:42:30 +0000 Note to requester: The attachment is immediately following this email.

To:

Purtscher, Patrick;Tregoning, Robert;Ramuhalli, Pradeep (Pradeep.Ramuhalli@pnnl.gov)

Subject:

RE: Workshop Summary Report Attachments:

Harvesting Workshop Summary Report draft 5-16-17.docx Sending the latest version with a few references to past research on harvested materials...

Matthew Hiser Materials Engineer US Nuclear Regulatory Commission I Office of Nuclear Regulatory Research Division of Engineering I Co1TOsion and Metallurgy Branch Phone: 30 l-415-24541 Office: TWFN I 0D62 Matthew.Hiser@nrc.gov From: Hiser, Matthew Sent: Friday, May 12, 2017 5:24 PM To: Purtscher, Patrick; Tregoning, Robert ; Ramuhalli, Pradeep (Pradeep.Ramuhalli@pnnl.gov)

Subject:

Workshop Summary Report Hi Pat, Rob, and Pradeep, I'd like to share with you a largely complete initial draft of the harvesting workshop summary report. I tried to capture the important points of the presentations and discussion at the workshop and then synthesize that down to "key takeaways" (I am open to a better term, but that's what I came up with). I still need to fill in the section on "References to Past Harvested Materials Research", but otherwise consider this a complete draft.

Please feel free to review and comment the overall organization, level of detail, etc. You can also review the specific wording with edits and tracked changes if you'd like, although I'd suggest not spending too much effort down in the weeds at this point.

My hope is to get some feedback in the next 2 weeks from this group and then share with the broader group of workshop attendees by the end of May for their review and input with a target to finalize this report by the end of June.

Thanks and please let me know if you have any questions!

Matt

Harvesting Workshop Summary Report

Background

On March 7-8, 2017, the Office of Nuclear Regulatory Research of the United States Nuclear Regulatory Commission (NRC) hosted a 2-day workshop on the topic of "Ex-Plant Materials Harvesting." NRC staff worked in close coordination with staff from the U.S. Department of Energy (DOE) and the Electric Power Research Institute (EPRI) to plan and arrange the workshop.

The decision to organize this workshop was driven by developments in the U.S. and global nuclear industry. In the U.S., there is strong interest in extending plant lifespans through subsequent license renewal (SLR) from 60 to 80 years. Extended plant operation and SLR raise a number of technical issues that may require further research to understand aging mechanisms, which may benefit from harvesting.

Meanwhile, in recent years, a number of nuclear plants, both in the U.S. and internationally, have shut down or announced plans to shut down. Unlike in the past when there were very few plants shutting down, these new developments provide opportunities for harvesting components that were aged in representative light water reactor (LWR) environments. In a related development, economic challenges for the nuclear industry and limited government spending have limited the resources available to support new research, including harvesting programs. Given this constrained budget environment, aligning interests and leveraging with other organizations is important to allow maximum benefit and value for future research programs.

Objective and Approach The objective of the workshop was to generate open discussion of all aspects of ex-plant materials harvesting, including:

1.

Deciding whether to harvest,

2.

Planning and implementing a harvesting program,

3.

Using the harvested materials in research programs.

Through presentations and open discussion, the workshop was organized to allow for all participants to be better informed of the benefits and challenges of harvesting as well as to identify potential areas of common interest for future harvesting programs. Workshop sessions were aligned in broad topics to cover all aspects of harvesting, but allow for participants to drive the discussion.

To help accomplish the workshop objectives, the workshop organizers intentionally sought a diverse group of participants. There are a large number of decommissioning plants and interested researchers outside the U.S., so the organizers focused on outreach to international participants through connections such as IAEA, OECD/NEA, and existing professional contacts. In addition, a key goal for this workshop was to capture the broader practical perspective from plant owners and decommissioning companies, which are vital to any successful harvesting program, but may sometimes be overlooked in researcher-driven discussions. Workshop participants were also diverse in terms of technical area of focus, with metal components such as the reactor pressure vessel (RPV) and internals being discussed along with concrete and electrical components. The final list of workshop participants can be found at the end of this report in Appendix I.

1

Workshop Organization and Sessions The workshop was held at NRC headquarters in Rockville, MD. Due to limited space in the meeting room and the need for a limited group size for discussion, a webinar was used to allow remote observers to benefit from the workshop. Workshop sessions were organized topically with about half the time dedicated to presentations and the remaining time set aside for discussion. Presentations were solicit ed from participants to cover a range of perspectives and technical areas. The final workshop agenda can be found at the end of this summary report in Appendix II.

The workshop was organized into five sessions as follows:

Session 1 Motivation for Harvesting Session 2 Technical Data Needs for Harvesting Session 3 Sources of Mate rials Session 4 Harvesting Experience: Lessons Learned and Practical Aspects Session 5 Future Harvesting Program Planning Summary of Workshop Discussion The subsections below will summarize the presentations and discussion in each session and highlight the key takeaways from the session.

Session 1 Motivation for Harvesting Session 1 focused on the motivation for harvesting and why workshop participants are interested in harvesting. Presentations were provided in this session by:

Richard Reister from DOE, Sherry Bernhoft from EPRI, Robert Tregoning from NRC, Uwe Jendrich from the Gesellschaft fur Anlagen-und Reaktorsicherheit (GRS) in Germany, and Taku Arai from the Central Research Institute of the Electric Power Industry (CRIEPI) in Japan.

Presentation Summaries DOE described the role of harvesting within the Light Water Reactor Sustainability (LWRS) Program, including the benefits and challenges associated with harvesting. Benefits include t he opportunity to fill knowledge gaps where there is limited data or experience and to inform degradation models wit h data from actual plant components. Challenges include cost, complexity, scheduling, logistics, limited opportunities, acquiring sufficient material pedigree information, and potent ial negative resullts impacting operating plants.

EPRI discussed the role of harvesting within the context of aging management for Long-Term Operations (LTO), including their experience from past harvesting programs and criteria for future harvest ing. Their experience emphasized the challenges of cost, schedule, logistics, complicated contracting and acquiring material pedigree information. EPRl's criteria for harvesting include value to their members that addresses a prioritized need and knowledge gap that cannot be otherwise filled through other means.

2

For EPRI, a well-developed project plan that covers funding, risk management, exit ramps, and clear roles and responsibilities is essential.

NRC shared its perspective on the benefits and challenges of harvesting in regulatory research.

Harvested materials are valuable due to the representative nature of their aging conditions, which may reduce the uncertainty associated with the applicability of the results to operating plants compared to tests with alternative aging conditions. Harvested materials may be the best option to address technical data needs identified for extended plant operation. Increasing harvesting opportunities from decommissioning plants suggests a proactive approach to harvesting planning may optimize benefits by identifying the appropriate material with the aging conditions of interest for the identified knowledge gap. There are significant challenges associated with harvesting, including cost, schedule, and logistics, but hopefully these can be mitigated or avoided by leveraging with other organizations and learning from past experience.

GRS described its role as the main technical support organization in nuclear safety for the German federal government. GRS provides technical assessment and knowledge transfer for decommissioning activities, aging management, and long-term operation for German federal and international organizations.

CRIEPI discussed its view of how harvested materials and laboratory prepared materials contribute to addressing technical issues. Harvested materials provide exposure to actual plant conditions, but are more limited in availability and the size of the data set that can be generated. Laboratory prepared materials general involve accelerated or simulated aging conditions, but can be used to produce larger data sets and varying parameters can allow understanding of the effect on the mechanism or property of interest. Harvested materials offer fact finding of actual plant conditions as well as confirmation and verification of results from laboratory prepared specimens.

Discussion Summary The discussion following the presentations in this session focused on clearly identifying the need to be addressed by a harvesting project and the myriad cost, scheduile, and logistical challenges associated with harvesting. Leveraging with other organizations to defray costs can also help improve the value of a given program, but also adds complexity as another organization may have a different set of priorities that changes the focus of the harvesting effort.

Session 2 Technical Data Needs for Harvesting Session 2 focused on discussing the technical data needs for harvesting and what specific knowledge gaps organizations are interested in addressing through harvesting. This discussion included general perspectives on how to determine when harvesting should be pursued rather than other types of research. Presentations were provided in this session by:

Pradeep Ramuhalli from the Pacific Northwest National Lab (PNNL),

Matthew Hiser from NRC, Keith Leonard from Oak Ridge National Laboratory (ORNL),

Rachid Chaouadi from SCK-CEN in Belgium, and Arzu Alpan from Westinghouse.

3

Presentation Summaries PNNL presented their work, under a small NRC contract, to develop a systematic approach to prioritize data needs for harvesting. PNNL proposed five primary criteria for prioritizing harvesting:

Unique field aspects of degradation o

For example, unusual operating experience or legacy materials (composition, etc.) that be no longer available Ease of laboratory replication of environment-materia I combination o

For example, simultaneous thermal and irradiation conditions may be difficult to replicate or mechanism sensitive to dose rate may not be good for accelerated aging Applicability of harvested material for addressing critical gaps o

Prioritize harvesting for critical gaps over less essential data needs Availability of reliable in-service inspection (ISi) techniques for the material/ component o

If inspection methods are mature and easy to apply to monitor and track degradation, perhaps the effort of research with harvested materials is not needed.

Availability of material for harvesting o

The necessary materials/ components must be available to be harvested.

PNNL then presented their application of these criteria to four materials degradation issues as an example: electrical cables, cast austenitic stainless steel (CASS), reactor vessel internals, and dissimilar metal welds. Based on applying these criteria to the examples, PNNL concludes that electrical cables, CASS, and reactor internals are all higher priority for harvesting due to unique aspects of the degradation that are challenging to replicate in the lab. Meanwhile, dissimilar metal welds are of low priority due to the ease of replication in lab aging studies as well as the significant body of knowledge and research on the phenomena.

NRC presented a summary of data needs it is interested in pursuing through harvesting. These included RPV materials to validate fluence and attenuation models and to demonstrate the conservatism of regulatory approaches for transition temperature prediction. Other metal components of interest for harvesting would address data gaps in irradiated stainless steels, as well as improve understanding of inspection capabilities and fatigue life calculations. Electrical components of interest include low and medium voltage cables and other electrical components for degradation studies, and electrical enclosures and cables for fire research. Concrete components of interest include irradiated concrete, concrete undergoing alkali-aggregate reactions, post-tensioned structures, reinforcing steel, tendons, and spent fuel pool concrete to assess potential boric acid attack.

DOE/ORNL presented their perspective on data needs for harvesting and its role in providing validation of experimental and theoretical research. DOE performed a significant reactor pressure vessel (RPV) harvesting program at the Zion nuclear power plant to reduce uncertainties in the Master Curve methodology, validate modeling predictions and study flux and fluence attenuation effects. The harvesting is largely complete, but the testing program is currently underway. DOE also indicated interest in using harvested materials to validate its models for swelling and microstructural changes of stainless steel internals under LWR irradiation conditions. Harvesting concrete components would be of interest due to lack of literature data and the multiple dependent variables that may affect concrete 4

performance. Finally, DOE has been involved in harvesting cables from the Crystal River and Zion plants to address cable aging as a function of material composition and environment.

SCK-CEN presented their interest in a international cooperative program to harvest reactor pressure vessel (RPV) materials. SCK-CEN presented their survey of the literature for past testing programs of harvested RPV materials, and tlhe limitations of these past program. Key limitations include a lack of archive materials, generally lower temperatures, and poor surveillance programs and dosimetry. SCK-CEN then shared some thoughts on their criteria for a new harvesting efforts, including higher fluence levels and temperatures, available archive materials and reliable information on operating history, dosimetry and surveillance program. Other topics relevant to a new RPV harvesting effort include technical issues such as material variability and irradiation conditions as well as logistical and financial considerations.

The final presentation in Session 2 by Westinghouse focused on the need for harvesting irradiated concrete to better understand the threshold radiation level for significant strength reduction.

Westinghouse has installed ex-vessel neutron dosimetry (EVND) at a number of plants in the world and proposed to use these dosimetry measurements to validate fluence model calculations to better understand the uncertainty in these calculations. If concrete can be harvested at one of these plants with EVND data, then irradiated concrete properties from testing can be paired with fluence data to improve research benefits.

Discussion Summary Dosimetry capsules Westingflouse Dosimetry chain IJ The discussion following Session 2 presentations touched on a number of topics. EPRI shared that they developed a report related to the topics of session 2, but more narrowly focused on PWR internals.

MRP-320, "Testing Gap Assessment and Material Identification for PWR Internals," focuses on prioritizing opportunistic harvesting of stainless steel reactor internals components that may be removed from service following MRP-227 inspections. The methodology and approach in this report may be relevant to the broader harvesting data needs discussion. This report is not publicly available, but is available to EPRI member utilities.

Workshop participants discussed the criteria proposed by PNNL in the first presentation. One additional criteria suggested by EPRI was to consider fleet-wide vs. plant-specific applicability. More broadly applicable materials would be of greater interest for harvesting than those that represent conditions at only a few plants. Another criteria suggested is the availability of material pedigree information, such as composition, processing, environmental conditions (temperature, humidity, fluence, etc.). Another suggested criteria was the ease of harvesting. For example, highly irradiated internals are probably much more difficult and expensive to harvest than electrical cables or unirradiated concrete. This discussion would capture the idea of weighing costs vs. benefits as well as project risk. Further discussion touched on the idea that different organizations may prioritize the various criteria differently, but all will probably at least want to consider the same set of criteria.

5

Another key theme from this discussion was that a successful program should be guided by a clearly defined objective or problem statement to be addressed. This objective should be well-understood at the initiation of a program and used to guide decision-making through implementation of a harvesting project. This also raises a related point or potential criteria: the timeliness of the expected research results relative to the objective. If the results are needed in the next two years, but a harvesting project will not provide results for at least five years, that should be a strong consideration.

Session 3 Sources of Materials Session 3 focused on discussing sources of materials for harvesting. This discussion covered previously harvested materials as well as sources for new harvesting programs from operating or decommissioning plants. Both domestic and international sources of materials were discussed in this session.

Presentations were provided in this session by:

Matthew Hiser from NRC, Al Ahluwalia from EPRI, Tom Rosseel from DOE/ORNL, John Jackson from DOE/Idaho National Laboratory (INL),

Gerry van Noordennen from EnergySolutions, Arzu Alpan from Westinghouse, Uwe Jendrich from GRS, and Daniel Tello from the Canadian Nuclear Safety Commission (CNSC).

Presentation Summaries NRC presented their perspective on sources of materials for harvesting. First, NRC shared some of the harvested materials from past research programs that may be available, including irradiated stainless steel internals, RPV materials, nickel alloy welds, neutron absorber material, and electrical components.

NRC then summarized the recently and planned shutdown U.S. plants, including their design, thermal output, and years of operation, to provide participants with an idea of the potential sources from decommissioning U.S. plants. Finally, NRC shared a list of information that would be helpful to acquire from decommissioning plants to determine the value of components for harvesting. This information included plant design information (component location and dimensions), environmental conditions (temperature, fluence, humidity, stress, etc.) and operating history, material pedigree information (fabrication records), and inspection records (for interest in components with known flaws).

The next presentation from EPRI covered harvesting opportunities at decommissioning plants in Korea and Sweden. In Korea, Kori-1 is a Westinghouse 2-loop PWR (sister plant is Kewaunee) that wiill shut down in 2017 after 40 years of operation. Korea Hydro and Nuclear Power Central Research Institute (KHNP-CRI) is planning a comprehensive research program on long-term materials aging based on harvesting from Kori-1 and is seeking international participation in the harvesting effort. KHNP-CRl's plan is focused on metallic components, including RPV, internals, primary system components, steam generator materials. Harvesting is expected to occur in 2024 with testing to follow through 2030.

In Sweden, Vattenfall is currently harvesting in 2017-2018 RPV material from the decommissioning Barseback BWR units. This work is focused on irradiation embrittlement, including comparison of 6

(b )(4)

(b)(4)..

surveillance data to actual RPV properties, as well as thermal aging embrittlement. In the future, Vattenfall will be shutting down Ringhals 1 and 2 in 2020 and 2019, respectively. Ringhals 1 is a BWR and Ringhals 2 is a Westinghouse 3-loop PWR design. Of particular note, Ringhals 2 has the second oldest replaced Alloy 690 RPV head and steam generators. Other harvesting opportunities at Ringhalls include RPV material with a significant surveillance program, thermal aging effects on low alloy steel from the pressurizer, as well as concrete structures. Vattenfall is open to working with partners that are interested in joining them for harvesting at Ringhals.

(b )( 4)

The next presentation by DOE/ORNL focused on several harvesting programs that DOE's LWRSprogfam has been involved with. DOE has led the harvesting of components from the Zion!

blantQin.......{~)(4) the U.S. From Zion, DOE has harvested electrical cables and components, a large RPV section, and a significant amount of records to provide information on material fabrication, in-service inspection and operating history. Cables from Zion include CROM, thermocouple, and low and medium voltage cables.

DOE indicated some thermocouple cables from Zion may be available for other researchers to use in collaborative studies. !

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DOE is also participating in efforts to harvest cables from Crystal River (led by EPRI) and concrete from the Zorita plant in Spain (led by NRC).

The next presentation by DOE/I NL described IN L's Nuclear Science User Facilities (NSUF) and the Nuclear Fuels and Materials Library (NFML). NSUF is coordinated by INL and facilitates access to nuclear research facilities around the world, including neutron and ion irradiations, beamlines, hot cell testing, characterization and computing capabilities.

NFML is a Web-based searchable database sample library that captures the information from thousands of specimens available to NSUF. NFML is designed to maximize the benefit of previously irradiated materials for future research. Researchers can propose new research projects under NSUF using specimens in NFML using DOE funding. The information captured in NFML aligns well with the goal of this session to potentially develop a database of previously harvested materials.

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..J The next presentation by EnergySolutions offered a more practical perspective on considering sources of materials for harvesting. From the plant owner perspective, in the decommissioning process there is not a financial incentive to support harvesting, therefore researchers need to absorb costs for harvesting and have a clear scope for harvesting. Flexibility in funding for harvesting activities is essential as the decommissioning process and schedule may change quickly.

EnergySolutions provided valuable perspective on the timing in the decommissioning proves for harvesting different components. Harvesting RPV surveillance coupons should take place when the RPV internals are cut and removed. Harvesting RPV materials is only possible from larger RPVs, as smaller RPVs are shipped intact to the disposal facility, rather than cut into pieces. Spent fuel rack neutron absorber coupons must be harvested either before or after dry storage campaign to remove spent fuel 7

from spent fuel pool. Harvesting actual spent fuel rack neutron absorber material must come after pool is completely empty. Electrical cables and other components from mild environments may be harvested at any time (once temporary power is established and plant power is shut off), while electrical components from high rad environments will depend on timing of source term removal schedule.

Concrete cores are best harvested when other cores are being taken for site characterization to develop the License Termination Plan. Highly irradiated concrete from !biological shield wall would need to come later in decommissioning after RPV is removed.

In terms of upcoming decommissioning plants, EnergySolutions indicated that San Onofre and Vermont Yankee will be entering DECON is 2018 and 2019, respectively. Kewaunee, Crystal River, and Fort Calhoun also may enter DECON in next 2 years. If researchers are interested in harvesting from any of these plants, they should be reaching out to plant owners immediately to begin planning and coordination.

Westinghouse followed their presentation in session 2 by describing an opportunity to harvest concrete from the Mihama 1 plant in Japan. Westinghouse installed and analyzed additional neutron dosimetry in the reactor cavity for one cycle, which were used to validate the radiation transport calculations.

Mihama was shutdown in 2015 and is in contact with Westinghouse about the possibility of extracting concrete cores from the biological shield wall. Westinghouse is seeking partners interested in joining this harvesting effort.

The next presentation by GRS covered opportunities for harvesting from German plants. Regulations in Germany require plants to either immediately dismantle or dismantle after a period of safe enclosure, which is largely consistent with options in the U.S. GRS detailed the status of German commercial reactors, which are predominantly BWR and PWR designs. Seventeen reactors are currently undergoing decommissioning, while seven more are currently shutdown and await a decommissioning license. Eight reactors are still operating with scheduled shutdown dates bet ween 2017 and 2022. German RPVs tend to have lower fluence that U.S. designs due to a larger water gap in the downcomer region. Germany has limited experience with harvesting from decommissioning plants. One question that GRS will follow-up on is the "rumored" cable surveillance programs that may be used in Germany and could provide experience and lessons learned for other countries.

The final presentation in Session 3 was by CNSC on harvesting opportunities in Canada. Atomic Energy Canada Limited (AECL) has harvested seven concrete cores from the 20 MW Nuclear Power Demonstration Plant (NPD), which shutdown in 1988 after 25 years of operation. CNSC and AECL are also considering opportunities to harvest concrete from other decommissioned reactors in Canada such as Gentilly-2, Douglas Point, and Whiteshell Reactor 1. In addition to concrete, CNSC and AECL are currently harvesting electrical cables from the 675 MWe CANDU-6 Gentilly-2 reactor, which shutdown in 2012 after 29 yea rs of operation. The purpose of this work is to study cable degradation from thermal aging and radiation damage and validate environmental qualification of the cables. CNSC described some of the challenges with this harvesting effort, such as working with plant owners, records, accessibility and contamination of the materials and budgeting with unexpected delays in harvesting.

A future harvesting opportunity is from the National Research Universal (NRU) reactor at Chalk River, which will shut down in 2018 after operating since 1957. AECL is currently taking an inventory of irradiated materials that can be harvested from NRU in decommissioning. Potential materials for 8

harvesting include metals (steels, nickel alloys, zirconium, aluminum), concrete, graphite, active equipment (pumps, etc.), graphite seals, electrical cables, and thermocouples.

Discussion Summary Following the presentations, there was some discussion of lessons from DOE's Zion harvesting effort.

DOE worked with a former senior reactor operator at Zion to identify and acquire the appropriate records from Zion for the components being harvested. DOE also described their flexible approach to acquiring RPV samples by sending a large chunk of material (weighing ~go tons) to EnergySolutions' facility in Tennessee, where smaller pieces (weighing ~soo pounds) were cut t o send to ORNL. Most of the decontamination was performed at Zion, with minimal additional cleaning (as well as cladding removal) taking place at EnergySolutions' facility.

There was also discussion of acquiring materials from sources other than commercial nuclear facilities.

DOE has considered harvesting concrete from other DOE nuclear facilities, but determined that there were compositional differences between the DOE facilities and commercial that would make them not useful. DOE/I NL mentioned that the Advanced Test Reactor (ATR) replaces their core internals every ten years. The ATR internals are composed primarily of 347 stainless steel and achieve very high fluence levels after ten years of service.

Another key discussion topic was the possibility of developing a database for previously harvested materials or those available for future harvesting. DOE/I NL indicated that their NSUF sample library may be a good starting point for such a database, although any materials in that library should be freely available for use in the research community. CNSC and NRC also expressed interested in working to develop a harvesting database.

Session 4 Harvesting Experience: Lessons Learned and Practical Aspects Session 4 focused on lessons learned and practical aspects of harvesting. Presenters shared their experience with past harvesting programs, particularly common pitfalls to avoid and successful strategies to overcome them. Presentations also covered the practical aspects of harvesting from the plant owner and decommissioning company perspective.

Presentations were provided in this session by:

Jean Smith from EPRI, Tom Rosseel from DOE/ORNL, Matthew Hiser from NRC, Taku Arai from CRIEPI, Gerry van Noordennen from EnergySolutions, and Bill Zipp from Dominion.

Presentation Summaries EPRI presented their experience and lessons learned from past harvesting programs, particularly harvesting reactor internals and concrete from Zorita and electrical cables from Crystal River. From the Zorita reactor internals experience, EPRI emphasized that harvesting projects take significant time, encounter material retrieval and on-site challenges, and shipping issues. In terms of time, ZIRP took 9

about 10 years to go from initial planning to final results, which included about 5 years of project planning, 2 years for material extraction (on-site logistics and shipping), and 3-4 years for testing. EPRl's experience was decommissioniing activities were the top priority and harvesting were subject to schedule and logistical challenges based on the changing decommissioning schedule. Shipping issues were also challenging due to sending activated materials (which were classified as "waste") across international borders, from the reactor in Spain Zorita Internals Research Project Timeline to testing facility in Sweden. Further planned shipments of the Zorita materials beyond the initial program continue to be impact by export license challenges in Sweden. More positively, EPRI emphasized that the Zorita reactor internals materials harvesting showed excellent "roj,ectln<<poll "1

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cooperation among many organizations and are providing valuable technical information to numerous research projects.

Lessons learned from the Zorita concrete harvesting focused on the challenges with core sample drilling and handling contaminated concrete. Ultimately, an effective core drilling procedure was identified, but required some trial and error. Lessons learned from the Crystail River cable harvesting included material concerns, the need for on-site support, and cost. In terms of material concerns, radiation and asbestos contamination created additional challenges for harvesting. On-site support and the ability to visit the site are extremely valuable to ensure clear communication, retrieval or records for material pedigree information, and awareness of on-site developments in the decommissioning process. Cable harvesting at Crystal River was more expensive than anticipated, particularly in terms of EPRI project management time to coordinate the harvesting activities and engineering support at the plant.

DOE presented lessons learned primarily from the experience harvesting RPV materials and electrical cables and components from the Zion plant. In terms of planning and decision-making, DOE had several lessons learned. DOE hosted a workshop at Zion in 2011 to discuss long-term goals and objectives, which proved very helpful in setting priorities and developing partnerships with other organizations.

Partnerships were very valuable to DOE's harvesting efforts, allowing for leveraging resources and collaboration and sharing results. There are limited opportunities for harvesting key components, so take full advantage of the opportunities that arise, understanding that there is a necessary compromise between the materials available and their value in terms of fluence or exposure to aging conditions.

Another consideration is the quantity of material harvested, which should be sufficient for the objectives of the planned research as well as any collaborations or partnerships, but limited to control costs.

For implementing the harvesting program, DOE found that flexibility was paramount to be ablle adjust scope and plans in response to schedule changes and other developments, while remaining within cost constraints. Working with a former reactor operator was extremely valuable to benefit from t heir in-depth knowledge of all parts of the plant, in particular the records for materials pedigree information.

Regular site visits and contacts were also essential to stay aware of the latest developments in the harvesting planning and decommissioning process, with the understanding that harvesting is not the top priority for decommissioning company. Other important considerations were hazardous materials handling, transportation, and disposal and logistics, including contracts, liability, shipping and disposal.

Finally, DOE's experience is that the total costs of a harvesting program from planning to execution to 10

testing are very high, so they should be carefully weighed against the value of the expected data to be generated.

NRC presented their experience, including benefits from previous harvesting programs, and technical and logistical lessons learned from harvesting. As an organization, NRC has extensive experience with testing harvested materials, including RPV, primary system components, reactor internals, neutron absorbers, concrete and electrical components. NRC's experience is more limited than DOE or EPRI in terms of managing the logistics of a harvesting effort from a decommissioning plant. NRC has generally participated in a secondary role in cooperative efforts or received failed components from operating plants for research. NRC has found that previous harvesting efforts have been effective in reducing unnecessary conservatism, understanding in-service flaws more realistically for NDE and leak rate methodologies, as well as identifying and better understanding safety issues.

For technical lessons learned, NRC's perspective is that harvesting can provide highly representative aged materials for research, which may be the only practical source of such materials. Harvested materials can be effectively used to validate models or a larger data set from accelerated aging tests. It is important understand as much as possible about the materials and their environment in service and how this compares with the operating fleet of reactors before committing to a specific harvesting project. For logistical lessons learned, harvesting is expensive and time-consuming, so a high technical benefit is needed to ensure the program provides values. Leveraging with other organizations can help minimize costs, but can also introduce challenges for aligning priorities and interests of multiple organizations. Finally, transporting irradiated materials, particularly between countries, challenging and time-consuming and should be avoided if at all possible.

CRIEPI presented their research experience with harvested materials as well as ongoing harvesting from the Hamaoka 1 plant. The first research program involved atom probe tomography (APT) on RPV surveillance materials. CRIEPI found a correlation between the volume fraction of Ni-Si-Mn clusters and the change in nil-ductility temperature. In the second research project, CRIEPI characterized t lhe weld and base materials harvested from Greifswald Unit 4 RPV with small-angle neutron scattering, APT, and hardness testing. In the third research project, CRIEPI performed APT on 304L stainless steel reactor internals harvested from control rod and top guide components from 3-13 dpa. Results showed a strong increase in Ni-Si clusters with increasing fluence, but little variation in Al enriched clusters with increasing fluence.

For future work, CRIEPI is collaborating with DOE LWRS to investigate RPV materials harvested from Zion (b)(4)

I FRIEPI also presented activities underway by Chubu Electric Power to harvest RPV and concrete samples from the IHamaoka 1 plant. Hamaoka 1 is a 540 MW BWR-4 that operated for 33 years. Harvesting began in 2015 and will continue through 2018.

The final two presentations of Session 4 provided the non-researcher perspective from a decommissioning company and plant owner. EnergySolutions, which is decommissioning the Zion nuclear plant among other facilities, presented the decommissioning process and their experience and lessons learned from harvesting at Zion. As mentioned previously, surgical harvesting is not the top priority for decommissioning, so researchers must recognize this and coordinate close with the decommissioning company. EnergySolutions emphasized the need to gain senior management support at the plant as well as to expect that there may be staff turnover during a multi-year harvesting effort.

Changes in scope and schedule (originating from both sides) can cause frustration on both sides. Early 11

planning and delays with contracting are important to avoid lost opportunities. Being on-site during harvesting is essential to a good outcome.

At Zion, EnergySolutions worked with DOE to harvest RPV materials, cables, electrical components, and spent fuel storage racks. DOE hoped to harvest a particular RPV surveillance capsule, but was unable to due to the inability identify the correct capsule. There were also challenges with harvesting RPV materials. The cut line on the Unit 2 RPV was too close to the weld to be used for research; fortunately, a successful specimen was harvested from Unit 1. For cabling, the initial plan was to harvest from 11 different locations, but ultimately due to unforeseen challenges and poor communication and coordination, only 4 different cable locations were harvested. Harvesting the desired cable length (30 feet) also proved challenging, with only shorter sections recovered. Plant records searches were largely effective at providing material pedigree information for cables. Concrete coring was initially pllanned to take place at Zion, but not performed due to lack of research interest. The spent fuel storage rack harvesting went smoothly, which was assisted by efforts over the weekend when decommissioning activities were not occurring.

The next presentation from Dominion provided its perspective on harvesting from decommissioning plants, focused on the experience at Kewaunee Power Station. The top priority (beyond safety) in decommissioning is the preservation and good stewardship of the decommissioning trust fund. Staffing is the largest drain on the trust fund, so at Kewaunee staff was halved within a few months of shutdown and then halved again about 16 months after permanent shutdown once offsite emergency response requirements were eliminated. Dominion described the example of harvesting the RPV surveillance capsules at this point at Kewaunee and the significant challenges that would exist. Given the reduced staffing and the current plant state (reactor coolant system drained, pumps retired, crane and radiation monitoring not maintained), it would be much more difficult now than immediately after shutdown.

Kewaunee considered harvesting the surveillance specimens and estimated a cost of six to seven figures based on all the activities required to enable it at this point po.st-shutdown compared to a much lower cost just after shutdown. Dominion observed that some components, such as cables or electrical components, may be available and relatively easy to harvest at almost any time during decommissioning. However, other components such as highly irradiated internals or RPV may be best harvested either shortly after shutdown when staffing and capabilities on-site are high or wait until active demolition of the reactor, which may be years or decades later.

Dominion also touched on the discussion of records for plant components. Records requirements are limited to those needed for safety. Once the plant shuts down and the range of potential safety concerns decreases, systems are downgraded to non-safety and the associated records are no longer required to be maintained. For perspective, Kewaunee still has all its records four years since shutdown, but will likely not continue this much longer. Dominion closed its presentation with a broader perspective on harvesting, emphasizing the need to clearly define a problem statement and understand what technical and regulatory purpose this harvesting will serve. Early planning focused on achieving the clear objective of the work incliuding scope, schedule, budget and contact with plant is essential to a successful harvesting effort.

12

Discussion Summary The discussion touched on the top lessons learned from past harvesting efforts, which included a clear objective and purpose for harvesting, early engagement with the plant, and site coordination during harvesting.

Another suggestion was to get utility management buy-in for the harvesting project by identifying a benefit to the utility. EPRI mentioned that cable harvesting at Crystal River went much more successfully once the utility recognized the potential benefits for subsequent license renewal. Similarly, when harvesting from an operating plant, you need to recognize and work through the challenges the plant may encounter when restarting operations.

During discussion, the question was raised regarding how it is determined whether harvested materials are waste. The discussion concluded that in the U.S. 10 CFR 37 is the important consideration. 10 CFR 37 defines when additional security requirements are imposed, based on the quantity and activity of materials to be transported. The definition of material as waste versus research materials is not as critical in the U.S. EnergySolutions indicated that their shipments of waste or research material could be handled in the same way in the accordance with Department of Transportation regulations, provided that the limits in 10 CFR 37 were not reached.

Session 5 Future Harvesting Program Planning Session 5 focused on the information needed for informed harvesting decision-making and harvesting program planning. This session featured a presentation by Pradeep Ramuhalli from PNNL, followed by a discussion period covering harvesting program planning and reflection on the 2-day workshop.

Presentation Summary PNNL presented its perspective on the information needed for informed harvesting decision-making.

First, the purpose of the harvesting effort needs to be defined by identify the technical knowledge gaps to be addressed. Next, a research plan should be developed demonstrating how the harvested material will be used to address the identified gaps. Finally, the appropriate source of material to address the technical gap must be identified, along with resources to support the effort and plans and timelines to perform the harvesting. The specifics of these plans depend greatly on the source of materials and must be flexible based on changing conditions on the ground.

In assessing the best source of materials, researchers should consider the material, its environment, and its condition. Material information includes fabrication information such as manufacturer, composition, and dimensions as well as information related to installation or construction, such as welding processes and parameters. Environmental information includes temperature, humidity, fluence, flux, stress (service, residual, installation), and coolant chemistry. Component condition information includes inspection history, such as identified flaws or degradation.

Discussion Summary The discussion in Session 5 focused on the best practical approach to plan future harvesting programs.

There was clear agreement thait this approach must begin with identifying the data needs best addressed by harvesting, whether from operating or decommissioning plants. Once a specific need is 13

identified, the next step is to find a source to acquire the materials of interest as well as other organizations interested in participating in the harvesting effort.

Key Takeaways from Workshop Session 1 The clear takeaway from the discussion in session 1 was that harvesting requires significant resources to be done successfully; therefore it is paramount to identify how the planned harvesting will clearly address a significant need to ensure the harvesting project provides strong value. In the context of need for data, EPRI suggested the goal of harvesting to support research for operation out to 80 years is not a full comprehensive understanding of all aspects of the degradation, but rather a snapshot to confirm other lab results and models. This is an important point for all organizations and researchers to keep in mind before investing significant resources in harvesting.

Session 2 The criteria proposed by PNNL are a good starting point for prioritizing issues to address by harvesting.

Three additional important criteria would be:

Fleet-wide vs. plant-specific applicability of data, Ease of harvesting (in terms of cost and project risk), and Timeliness of the expected research results relative to the objective.

Once a potential harvesting project has reached the point of looking at different sources of materials, the availability of material pedigree information, such as composition, processing, environmental conditions (temperature, humidity, fluence, etc.) is very important to the overall value of harvesting from that particular plant.

Based on the presentations and discussion in Session 2, there appeared to be two areas with broad interest in pursuing further harvesting: high fluence reactor internals and irradiated concrete. The common drivers for the interest in these issues is a lack of representative data at the fluences of interest and significant challenges with acquiring representative data through other means. High fluence reactor internals has been addressed somewhat by the Zorita Internals Research Project (ZIRP), but stainless steel materials exposed to higher fluence levels at higher temperatures, where void swelling may become significant, could help validate DOE and EPRI models and provide further technical baisis for PWR internals aging management. Irradiated concrete harvesting is currently being pursued from the Zorita reactor in Spain, with international collaboration and potential testing at the Halden Reactor Project.

Other areas with some, but less widespread, interest expressed from workshop participants for new harvesting efforts included RPV materials and electrical cables and components. SCK-CEN and NRC expressed interest in RPV harvesting, and NRC expressed interest in electrical component harvesting.

Session 3 To capture the key takeaways from Session 3 focused on sources of materials, two tables of potential sources of materials are presented below. The first table covers recent or ongoing harvesting !Programs, while the second details potential future harvesting opportunities.

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Ongoing Harvesting Programs Country Plant Design Size Years in Components Organization(s)

(MWe) operation Canada NPD CANDU 20 25 Concrete AECL Gentilly-2 CANDU-6 675 29 Cables Japan Hamaoka 1 IBWR-4 540 33 RPV, concrete CRIEPI/Chubu Spain Zorita W 1-loop 160 37 Internals, concrete EPRI, NRC Sweden Barseback ABB-II 615 28 RPV Vattenfall Zion 1/2 W-4 1040 24/25 RPV, cables, DOE, EPRI, NRC loop neutron absorbers U.S.

Crystal River 3 B&W 860 36 Cables EPRI (b )( 4)

Potential Future Sources for Harvesting Country Plant Design Size Years in Potential Notes

{MWe) operation Components Canada NRU Test reactor 135 61 TBD AECL; SD:

MWt 2018 Germany Numerous plants either in decommissioning or shutting down soon. See Appendix Ill.

Japan Mihama W 2-loop 320 40 Concrete

Kansai, Westinghouse RPV, internals, Korea Kori 1 W 2-loop 576 40 SGs, pressurizer, KHNP, EPRI welds, CASS, Ringhals 1 BWR 883 44 RPV, internals Vattenfall; Sweden Ringhals 2 W 3-loop 900 44 SGs, pressurizer, SD: 2020 /

concrete 2019 Kewaunee W 2-loop 566 39 TBD SD: 2013 SONGS 2/3 CE 2-loop 1070 31/30 TBD SD: 2013 Crystal River 3 B&W 860 36 TBD SD: 2013 Vermont BWR-4/Mk-1 605 42 TBD SD:2015 Yankee Fort Calhoun CE 2-loop 482 43 TBD SD:2016 Palisades CE 2-loop 805 47 TBD SD:2018 Pilgrim BWR-3/Mk-1 677 47 TBD SD: 2019 U.S.

Oyster Creek BWR-2/Mk-1 619 50 TBD SD:2019 Indian Point W 4-loop 1020 /

48/46 TBD SD:2021 2/3 1040 Diablo Canyon W 4-loop 1138/

40 TBD SD: 2024-5 1/2 1118 Non-Advanced 250 commercial; Test Reactor Test reactor MWt 50 Core internals internals replaced every 10 years 15

In addition to the potential sources of materials presented and discussed in Session 3, another takeaway was the suggestion of developing a database for previously harvested materials or those available for future harvesting. The NSUF sample library may be a good starting point for such a database, with appropriate modifications for the purposes of harvesting efforts.

Session 4 There were several important takeaways from Session 4 that were touched on in multiple presentations and the discussion. One key takeaway is that researchers should identify a clear purpose and scope for harvesting. Having a clear purpose for harvesting helps to guide later decisions that must be made to adjust course when the inevitalble changes in schedule or unexpected realities at the plant arise. A related note is that harvesting iis not the top priority for decommissioning. Therefore, researchers must have clear objectives and scope for harvesting that can be communicated to the site. This understanding should shape assumptions and interactions with the plant owner or decommissioning company as well as planning for costs and schedule.

Another takeaway was the value of strong site coordination, including site visits. Multiple presenters touched on the value of being on-site to talk to staff and see the components to be harvested. Mock ups and 3-D simulations can be valuable to ensure success of the approach or technique used to acquire the specimen. A related point is working with reactor operators at the plant. Several harvesting efforts worked with former reactor operators and benefited greatly from their experience to find records or determine the best method to harvest the desired component. This is a valuable insight that could be effective in future harvesting efforts.

A third key takeaway is early engagement with the plant to express interest in harvesting. This serves to make the plant aware of your interest in harvesting and get their support to work with the harvesting process. The other important benefit of early engagement is to gain as much information as possible about the available materials and components, including the associated records and material pedigree information.

Session 5 The key takeaway in session 5 was to gather as much information as possible in advance of committing to a specific harvesting project. Ideally, there would be a strong understanding that the material and its aging conditions clearly align with an identified technical data need before committing significant resources to a harvesting effort.

Action Items and Next Steps The following is a summary of the action items discussed at the end of the workshop:

1. Sharing workshop slides NRC emailed attendees to ask their comfort with sharing their workshop slides with other organizations and received no objection from any presenters.

The presentations can be accessed here:

https ://drive.google.com/ open ?id =OBS DWM LchSYSXcn pZZ0JOS0SSQU U.

16

2.

EPRI indicated that MRP-320 (Product ID: 1022866) on knowledge gaps for irradiated austenitic stainless steel for potential harvesting from MRP-227 inspections is publicly available for a fee.

3.

Cable surveillance programs in Germany GRS to inquire with cable colleagues and share any insights.

4. Sources of materials database Potential sources of materials presented in this workshop are summarized in Session 3 summary above and Appendix Ill below.

NRC will be reaching out to PNNL, INL NSUF, CNSC, AECL, and any other organizations interested in database development.

5.

Prioritized data needs Suggestion to continue discussions on prioritiz.ed data needs within technical areas (RPV, internals, electrical, concrete) through existing coordination groups if possible Focus on identifying specific material/ aging conditions of interest and purpose

/ intended outcome of harvesting Idea to survey Env Deg participants John Jackson (INL) is on planning committee

6.

EPRI report on spent fuel liner boric acid transport through concrete NRC will contact EPRI for report if needed.

7.

Harvested Materials Research Results Section of workshop summary report (below) devoted to references from harvested materials research.

References to Previous Harvested Materials Research This section of the workshop summary addresses a question that was raised during the discussion at the workshop regarding what the outcome or benefit of past harvesting efforts have been. Below is a list of references to research results generated from testing of harvested materials:

J.R. Hawthorne and A.L. Hiser, Experimental Assessments of Gundremmingen RPV Archive Material for Fluence Rate Effects Studies, NUREG/CR-5201 (MEA-2286), U.S. Nuclear Regulatory Commission, October 1988.

G. J. Schuster, S. R. Doctor, A.F. Pardini, and S.L. Crawford, Characterization of Flaws in U.S. Reactor Pressure Vessels: Validation of Flaw Density and Distribution in the Weld Metal of the PVRUF Vessel, NUREG/CR-6471 Volume 2, U.S. Nuclear Regulatory Commission, August 2000.

G. J. Schuster, S. R. Doctor, S.L. Crawford, and A. F. Pardini, Characterization of Flaws in U.S. Reactor Pressure Vessels: Density and Distribution of Flaw Indications in the Shoreham Vessel, NUREG/CR-6471 Volume 3, U.S. Nuclear Regulatory Commission, November 1999.

D. E. McCabe, et al. Evaluation of WF-70 Weld Metal From the Midland Unit 1 Reactor Vessel, NUREG/CR-5736 (ORNL/TM-13748), U.S. Nuclear Regulatory Commission, November 2000.

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B. Alexandreanu, O.K. Chopra, and W.J. Shack, Crack Growth Rates in a PWR Environment of Nickel Alloys from the Davis-Besse and V.C. Summer Power Plants, NUREG/CR-6921 (ANL-05/55), U.S. Nuclear Regulatory Commission, November 2006.

S.E. Cumblidge, et al. Nondestructive and Destructive Examination Studies on Removed-from-Service Control Rod Drive Mechanism Penetrations, NUREG/CR-6996, U.S. Nuclear Regulatory Commission, July 2009.

S.E. Cumblidge, et al. Evaluation of Ultrasonic Time-of-Flight Diffraction Data for Selected Control Rod Drive Nozzles from Davis Besse Nuclear Power Plant, PNNL-19362, Pacific Northwest National Laboratory, April 2011.

S.L. Crawford, et al. Ultrasonic Phased Array Assessment of the Interference Fit and Leak Path of the North Anna Unit 2 Control Rod Drive Mechanism Nozzle 63 with Destructive Validation, NUREG/CR-7142 (PNNL-21547), U.S. Nuclear Regulatory Commission, August 2012.

18

Appendix I Workshop Participants Name Organization Email Taku Arai CRIEPI arait@crieoi.denken.or.io Sadao Higuchi CRIEPI higuchi@criegi.denken.or.jg Japan Kazunobu Sakamoto JNRA kazunobu sakamoto@nsr.go.jg Yasuhiro Chimi JAEA chimi.yasuhiro@jaea.go.jg Uwe Jendrich GRS Uwe.Jendrich (ci) ins.de Europe Rachid Chaouadi SCK-CEN rachid.chaouadi@sckcen.be Guy Roussel BelV guy.roussel@Belv.be Daniel Tello CNSC daniel.tello@canada.ca Canada Desire Ndomba CNSC desire.ndomba@canada.ca Karen Huynh AECL kh uynh@aecl.ca Gerrv van Noordennen Energy Solutions 12ovannoordennen@energvsolutions.com us Bill Zipp Dominion william.f.zigg@dom.com industry Mark Richter NEI mar@nei.org Arzu Alpan Westinghouse alganfa@westinghouse.com Sherrv Bernhoft EPRI sbern hoftca>eori.com Robin Dyle EPRI rdy:le@egri.com EPRI Jean Smith EPRI jmsmith@egri.com Al Ahluwalia EPRI kahluwal@egri.com Tom Rosseel ORNL rosseeltmca>ornl.gov Rich Reister DOE Rich a rd. Reister@nuclea r.energy.gov Keith Leonard ORNL leonardk@ornl.gov DOE Mikhail A. Sokolov ORNL sokolovm@ornl.gov John Wagner INL john.wagner@inl.gov John Jackson INL john.jackson@inl.gov Pradeep Ramuhalli PNNL Pradeeg.Ramuhalli@gnnl.gov Pat Purtscher NRC Patrick. Pu rtscherca> nrc.12ov Rob Tregoning NRC Ro bert.Tregoning@nre.gov Matt Hiser NRC Matthew.Hiser@nrc.gov Mita Sircar NRC Madhumita.Sircar@nrc.gov Tom Koshy NRC Thomas.Koshy@nrc.gov NRC Jeff Poehler NRC Jeffrey. Poehler@nrc.gov Allen Hiser NRC Allen.Hiser@nrc.gov Angela Buford NRC Anigela.Buford@nrc.gov M ark Kirk NRC Mark.Kirk@nrc.gov Amy Hull NRC Amy.Hull@nrc.gov Pete Ricardella NRC/ACRS Pri cca rdel la@Structint.com 19

Session Time Intro 8:00 1

8:15-8:45 8:45 - 9:45 9:45-10:00 10:00-10:20 10:20-10:30 10:30 -

10:55 2

10:55 -

11:20 11:20 -

11:45 11:45 -

12:30 12:30- 2:00 2:00 - 2:10 2:10- 2:35 2:35-2:50 2:50 - 3:00 3:00- 3:15 3

3:15-3:30 3:30- 3:45 3:45-4:00 4:00-4:15 4:15-5:00 Appendix II Workshop Agenda Tuesday, March 7 Organization Speaker Presentation Title NRC Michael Weber Welcome and Introduction to Workshop Robert Tregoning DOE Rich Reister DOE Perspectives on Material Harvesting EPRI Sherry Bernhoft EPRI Perspective on Harvesting Projects NRC Robert Tregoning NRC Perspective on Motivation for Harvesting GRS Uwe Jendrich Role of GRS in Decommissioning and LTO CRIEPI Taku Arai CRIEPI Motivations for Harvested Material DISCUSSION BREAK PNNL (for NRC)

Pradeep Ramuhalli Data Needs Best Addressed By Harvesting NRC Matthew Hiser High-Priority Data Needs for Harvesting DOE Keith Leonard LWRS Program Perspective on the Technical Needs for Harvesting Review of past RPV sampling test programs SCK-CEN Rachid Chaouadi and perspective for long term operation Westinghouse Arzu Alpan Importance of Harvesting to Evaluate Radiation Effects on Concrete Prooerties DISCUSSION LUNCH NRC Matthew Hiser Sources of Materials: Past NRC Harvesting and U.S. Decommissioning Plants EPRI Al Ahluwalia Harvesting Plans for Materials Aging Degradation Research in Korea and Sweden DOE/ORNL Tom Rosseel Materials Harvested by the LWRS Program DOE/I NL John Jackson NSUF Material Sample Library Energy Solutions Gerry van Zion Material Harvesting Program Noordennen Potential Harvesting of Concrete from Mihama Westinghouse Arzu Alpan Unit 1 BREAK GRS Uwe Jendrich Plants in Decommissioning in Germany Evaluating Structures, Systems & Components CNSC Daniel Tello from Decommissioned/Decommissioning Nuclear Facilities in Canada DISCUSSION 20

Wednesday, March 8 Session Time Ori?anization Speaker Presentation Title 8:00-8:30 EPRI Jean Smith Lessons Learned: Harvesting and Shipping of Zorita Materials 8:30-9:00 DOE Tom Rosseel LWRS Program: Harvesting Lessons Learned 9:00 - 9:30 NRC Matthew Hiser NRC Perspective on Harvesting Experience and Lessons Learned 9:30 -10:00 CRIEPI Taku Arai CRIEPI Research Activities with Harvested 4

Materials 10:00 - 10:15 BREAK 10:15 - 10:45 Energy Gerry van Zion Harvesting Experience and Lessons Solutions Noordennen Learned 10:45 - 11:15 Dominion Bill Zipp Kewaunee Insights on Material Harvesting 11:15 - 12:00 DISCUSSION 12:00-1:30 LUNCH 1:30 - 1:45 PNNL (for Pradeep Ramuhalli Technical Information Needed for Informed NRC)

Harvesting Decisions 1:45-2:30 DISCUSSION 5

2:30 - 3:00 Action Items and Next Steps EPRI Sherry Bernhoft DOE Rich Reister Closing Thoughts 3:00 - 4:00 NRC Robert Tregoning ALL 21

Appendix Ill Harvesting Opportunities in Germany

• Past and current decommissioning projects of Prototype or Commercial Reactors Name Reactor type --

Strategy Rheinsberg KKR WWER 70 1995 UC Compact Natrium Cooled KKN SNR 21 1993 UC Reactor Multipurpose Research R.

MZFR PWR/O20 57 1987 UC Obrigheim KWO PWR 357 2008 UC Neckarwestheim 1 GKN-1 PWR 840 2017 UC lsar-1 KKl-1 BWR 912 2017 UC Gundremmingen-A KRB-A BWR 250 1983 RCA KRB-11 Greifswald 1-5 KGR 1-5 WWER 440 1995 UC Lingen KWL BWR 268 1985 UC after SE UC: unconditional clearance RCA: radiation controlled area, new license NRC Harvesting Workshop, Rockville, March 2017, Decommissioning In Germany SE: safe enclosure 4

• Past and current decommissioning projects of ? ototype or Commercial Reactors Name Stade Research Reactor Julich Thorium High-Temperature-Reaktor Wurgassen Mulheim-Karlich Hot-Steam Reactor Grosswelzheim N iederaichbach Test-Reactor Kahl KKS AVR THTR-300 KWW KMK HOR KKN VAK Reactor type PWR HTR HTR BWR PWR HOR ORR/O2O BWR 22 Strategy 672 2005 UC 15 1994 UC 308 1993 SE since 1997 670 1997 UC 1302 2004 UC 25 1983 UC since 1998 106 1975 UC since 1994 16 1988 UC since 2010

Shut down Cor1r1erc*a1 ~Qactors

• that have no decommissioning license granted yet Name Abbrev.

Reactor type PowerMWe Philippsburg-1 KKP-1 BWR 926 Grafenrheinfeld KKG PWR 1345 Biblis-A KWB-A PWR 1225 Biblis-B KWB-B PWR 1300 Unterweser KKU BWR 1410 BrunsbUttel KKB BWR 806 Krummel KKK BWR 1402

• Commercial Reacto In operation Name Abbrev.

Reactor type Power MWe Gundremmingen-B KRB-11-B BWR 1344 Philippsburg-2 KKP-2 PWR 1468 Gundremmingen-C KRB-11-C BWR 1344 Grohnde KWG PWR 1430 Brokdorf KBR PWR 1480 Emsland KKE PWR 1406 lsar-2 KKl-2 PWR 1485 Neckarwestheim-2 GKN-2 PWR 1400 23 Date of application 2013 / 2014 2014 2012 2012 2012 / 2013 2012 / 2014 2015 Anticipated date of final shutdown 31.12.2017 31.12.2019 31.12.2021 31.12.2021 31.12.2021 31.12.2022 31.12.2022 31.12.2022

From:

Sent:

To:

Subject:

19-17-lpm Attachments:

Hi Matt, Hull, Amy Fri, 19 May 2017 13:47:31 -0400 Hiser, Matthew Note to requester: The attachment is immediately following this email.

Reviewed with comments -- Harvesting Workshop summary Report draft abh 5-Harvesting Workshop summary Report draft abh 5-19-17-lpm.docx This is lovely work and it was a very productive workshop.

I have another suggestion for you --- I think it would be a great idea to also have this as a presentation for IAEA PLiM this Fall. At the last SMIRT, there were summary papers of workshops like this that were very valuable. Condensing wisdom of many people into a short presentation - but you get a refereed article out of it. I think the short abstracts have to be done soon (today?) so you might want to check with Rob or Carol about this.

=

Background===

Harvesting Workshop USNRC HQ

• March 7-8, 2017 Summary [Repor~

On March 7-8, 2017, the Office of Nuclear Regulatory Research of the United States Nuclear Regulatory Commission (NRC) hosted a 2-day workshop on the topic of "Ex-Plant Materials Harvesting." NRC staff worked in close coordination with staff from the U.S. Department of Energy (DOE)[ and the Electric Power Research Institute (EPRI) to plan and arrange the workshop.

The decision to organize this workshop was driven by developments in the U.S. and global nuclear industry. In the U.S., ~here is strong interest in extending plant lifespans through subsequent license renewal (SLR) from 60 to 80 years. Extended plant operation and SLR raise a number of technical issues that may require further research to understand aging111echanismJ1 which may benefit from harvesting.

Meanwhile, in recent years, a number of nuclear plants, both in the U.S. and internationally, have shut down or announced plans to shut down. Unlike in the past when there were very few plants shutting down, these new developments provide opportunities for harvesting components that were aged in representative light water reactor (LWR) environments. In a related development, economic challenges for the nuclear industry and limited government spending have limited the resources available to support new research, including harvesting programs. Given this constrained budget environment, aligning interests and leveraging with other organizations is important to allow maximum benefit and value for future research programs.

Objective and Approach The object ive of the workshop was to generate open discussion of all aspects of ex-plant materials harvesting, including:

1. Deciding whether to harvest,

2.

Planning and implementing a harvesting program,

3.

Using the harvested materials in research programs.

Through presentations and open discussion, the workshop was organized to allow for all participants to be better informed of the benefits and challenges of harvesting as well as to identify potential areas of common interest for future harvesting programs. Workshop sessions were aligned in broad topics to cover all aspects of harvesting, but allow for participants to drive the discussion.

To help accomplish the workshop objectives, the workshop organizers intentionally sought a diverse group of participants. There are a large number of decommissioning plants and interested researchers outside the U.S., so the organizers focused on outreach to international participants through connections such as IIAEA, OECD/NEA,\\ and existing professional contacts. In addition, a key goal for this workshop was to capture the broader practical perspective from plant owners and decommissioning companies, which are vital to any successful harvesting program, but may sometimes be overlooked in 1

Commented [HA1): This document is long enough and complicated enough and valuable enough, please think about adding linked table of contents so reader can go directly to a section.

Commented [HA2]: If this included PNNL folks on contract, then you should call out PNNL, since they are not DOE staff-National Lab scientists are not federal employees.

Commented [HA3]: Global comment - I t hink documents are easier to read when there are 2 spaces between sentences, but that is elective and optional.

Commented [HA4): Maybe restate the first sentence in this paragraph, lifespans e.tended through proactive management of materials degradation and SLR research1 etc

- operating time e*tended t hrough SLR.

Commented [HA5]: Global comment - define all acronyms In first use.

researcher-driven discussions. Workshop participants were also diverse in terms of technical area of focus, with metal components such as the reactor pressure vessel (RPV) and internals being discussed along with concrete and electrical components. The final list of workshop part icipants can be found at the end of this report in Appendix I.

Workshop Organization and Sessions The workshop was held at NRC headquarters in Rockville, MD. Due to limited space in t he meeting room and the need for a limited group size for discussion, a webinar was used to allow remote observers to benefit from the workshop. Workshop sessions were organized topically with about half the time dedicated to presentations and the remaining time set aside for discussion. Presentations were solicited from participants to cover a range of perspect ives and technical areas. The final workshop agenda can be found at the end of this summary report in Appendix II.

The workshop was organized into five sessions as follows:

Session 1, Motivation for Harvesting Session 2, Technical Data Needs for Harvesting Session 3, Sources of Materials Session 4, Harvesting Experience: Lessons Learned and Practical Aspects Session 5, Future Harvesting Program Planning Summary of Workshop Discussion The subsections below will summarize the presentations and discussion in each session and highlight the key takeaways from the session.

Session 1! Motivation for Harvesting Session 1 focused on the motivation for harvesting and why workshop participants are interest ed in harvesting. As shown in Appendix J9, providing presentation titles, speakers forpreselltati<>AS-were wovises iR this session includedey:

Richard Reister from DOE, Sherry Bernhoft from EPRI, Robert Tregoning from NRC, Uwe Jendrich from the Gesellschaft fur Anlagen-und Reaktorsicherhelt (GRS) in Germany, and Taku Arai from the Central Research Institute of the Electric Power Industry (CRIEPI) in Japan.

Presentation Summaries DOE described the role of harvesting within the Light Water Reactor Sustainability (LWRS) Program, including the benefits and challenges associated with harvesting. Benefits include the opportunity to fill knowledge gaps where there is limited data or experience and to inform degradation models with data from actual plant components. Challenges include cost, complexity, scheduling, logistics, limited opportunities, acquiring sufficient material pedigree information, and potential negative results impacting operating plants.

2

EPRI discussed the role of harvesting within the context of aging management for Long-Term Operations (LTO), including their experience from past hairvesting programs and criteria forfuture harvesting. Their experience emphasized the challenges of cost, schedule, logistics, complicated contracting and acquiring material pedigree information. EPRl's criteria for harvesting include value to their members that addresses a priorit ized need and knowledge gap that cannot be otherwise filled t hrough other means.

f or EPRI members, a well-developed proj~ct plan that covers funding, risk management, exit ramps, and clear roles and responsibilities is considered essential.

NRC shared its perspective on the benefits and challenges of harvesting in regulatory research.

Harvested materials are valuable due to the real-world nature of their aging conditions, w hich may reduce the uncertainty associated with the applicability of the results to operating plants compared to tests with alternative aging conditions. Harvested materials may be t he best option to address technical data needs identified for extended plant operation. )ncreasing harvesting opportunities from decommissioning plants suggest s a proactive approach to harvesting planning which may optimize benefits by identifying the appropriate material with t he aging conditions of interest for the identified knowledge gap.~ here are significant challenges associated with harvesting, including cost, schedule, and logistics, but hopefully these can be mitig.ated or avoided by ~everaging coordination with other organizations and learning from past experiericej GRS described its role as the main technical support organization in nuclear safety for the German federal government. GRS provides technical assessment and knowledge transfer for reactor decommissioning activities, aging management, and long-term operation for German federal and international organizations.

CRIEPI discussed its view of how harvested materials and laboratory prepared materials contribute to addressing technical issues. Harvested materials provide exposure to actual plant cond it ions, but are more limited in availability and the size of the data set that can be generated. Laboratory prepared materials general involve accelerated or simulated aging conditions, but can be used to produce larger data sets and varying parameters can allow understanding of the effect on the mechanism or property of interest. Harvested materials offer fact finding of actual plant conditions as well as confirmation and verification of results from laboratory prepared specimens.

Discussion Summary The discussion following the presentations in this session focused on clearly identifying the need to be addressed by a harvesting project and the myriad cost, schedule, and logistical challenges associated with harvesting. Sharing projects with other organizations to defray costs can also help improve t he value of a given program, but also adds complexity as another organization may have a different set of priorities that changes t he focus of t he harvesting effort.

Session 2! Technical Data Needs for Harvesting Session 2 focused on discussing the t echnical data needs for harvesting and what specific know ledge gaps organizations are interested In addressing through harvesting. -This discussion included general perspectives on how to determine when harvest ing should be pursued rather t han other types of research. As shown?fesefltations-wet'e-pmvidled in Appendix II, providing presentation titles, speakers for this session includedby:

3 Commented [HA6]: Sentence is a little awkward, consider rewriting

[ Commented [HA7): Too much, rewrite for clarity.

Commented [HAS]: There should be a noun following this verb form. leveraging what - insight, collaboration, coordination?

Pradeep Ramuhalli from the Pacific Northwest National Lab (PNNL),

Matthew Hiser from NRC, Keith Leonard from Oak Ridge National Laboratory (ORNL),

Rachid Chaouadi from SCK-CEN in Belgium, and Arzu Al pan from rNest inghouse.

Presentation Summaries f NNL presented their work, under a small NRC contract, to develop a systematic approach to prioritize data needs for harvesting. PNNL proposed five primary criteria for prioritizing harvesting:

Unique field aspects of degradation o

For example, unusual operating experience or legacy materials (composition, etc.) that may be no longer available Ease of laboratory replication of environment-material combination {degradation scenario) o For example, simultaneous thermal and irradiation conditions may be difficult to replicate or mechanism sensit ive to dose rate may not be good for accelerated aging Applicability of harvested material for addressing critical gaps o

Prioritize harvesting for critical gaps over less essential data needs Availability of reliable in-service inspection (ISi) techniques for the material / component o

If inspection methods are mature and easy to apply to monitor and track degradation, perhaps the effort of research with harvested materials is not needed.

Availability of material for harvesting o

The necessary materials/ components must be available to be harvested.

PNNL then presented their application of these criteria to four materials degradation issues as an example: electrical cables, cast austenitic stainless steel (CASS), reactor vessel internals, and dissimilar metal welds. Based on applying these criteria to t he examples, PNNL concludef!s that electrical cables, CASS, and reactor internals are all higher priority for harvesting due to unique aspects of the degradation that are challenging to replicate in the lab. Meanwhile, dissimilar metal welds are of low priority due to the ease of replication in lab aging studies as well as the significant body of knowledge and research on the phenomena.

NRC presented a summary of data needs it is interested in pursuing through harvesting. These included RPV materials to validate fluence and attenuation models and to demonstrat e the conservatism of regulatory approaches for transition temperature prediction. Other metal components of interest for harvesting would address data gaps in irradiat ed stainless steels, as well as improve understanding of inspection capabilities and fatigue life calculations. Electrical components of interest include low and medium voltage cables and other electrical components for degradation studies, and electrical enclosures and cables for fire research. Concrete components of interest include irradiated concrete, concrete undergoing alkali-aggregate reactions, post-tensioned structures, reinforcing steel, tendons, and spent fuel pool concrete to assess potential boric acid attack.

DOE/ORNL presented their perspective on data needs for harvesting and its role in providing validation of experimental and theoretical research. pOE performed a significant ~eaeter 11ress~re *,essel (RPvt

~arvesting program at the Zion nuclear power plant to reduce uncertainties in the Master Curve methodology, validate modeling predictions and study flux and fluence attenuation effects. The 4

Commented (HA9]: pis define SCK-CEN in line above, since this is the first time the acronym is used.

Commented (HA10]: Global comment, are you sure that you want to refer to organization In these sections, since the speaker may represent only themselves **- certainly Pradeep does not speak for PNNL.

Commented (HA 11 ]: Do you want to continue to use the term DOE/ORNL? If ORNL actually did the work, I think you should.

Commented (HA12]: Global comment - you only need to define acronym lX, the first time used *** RPV was defined on pg. 1

harvesting is largely complete, but t he testing. program is currently underway. DOE also indicated interest in using harvested materials to validate Its models for swelling and mlcrostructural changes of st ainless steel internals under LWR irradiation conditions. Harvesting concrete components would be of interest due to lack of literature data and the multiple dependent variables t hat may affect concrete performance. Finally, DOE has been involved in harvesting cables from the Crystal River and Zion plants to ad dress cable aging as a function of material composition and environment.

SCK-CEN presented their interest in an international cooperative program to harvest reaster presst1re vess,e4RPV} materials. SCK-CEN presented their survey of the literature for past testing programs of harvested RPV materials, and the limitations of these past program1. Key limitations include!! a lack of archive materials, generally lower temperatures, and poor surveillance programs and dosimetry. SCK-CEN then shared some t houghts on t heir criteria for a new harvesting efforts, including higher fluence levels and temperatures, available archive materials and reliable information on operating history, dosimet ry and surveillance program. Other topics discussed, relevant to a new RPV harvesting effort, include!! technical Issues such as material variability and irradiation conditions as well as logistical and financial considerations.

~he final presentation in Session 2 !by West inghouse focused on the need for harvest ing irradiated concrete to better understand the threshold radiation level for significant strength reduction.

Westinghouse has installed ex-vessel neutron dosimetry (EVND) at a number of plants in the world and proposed to use these dosimetry measurements to validate fluence model calculations to better understand the uncertainty in these calculations. If concrete can be harvest ed at one of these plants with EVND data, then irradiated concrete properties from testing can be paired with fluence dat a to improve research benefits.

Discussion Summary Dosimetry capsules Westingt,ouse Support bar Dosimetry chain The discussion following Session 2 presentations touched on a number of topics. EPRI shared that they developed a report related t o the topics of ~session 2, but more narrowly focused on PWR internals.

MRP-320, "Testing Gap Assessment and Material Identification for PWR Internals," focuses on prioritizing opportunistic harvesting of stainless steel reactor internals components t hait may be removed from service following MRP-227 inspections. The methodology and approach In this report may be relevant to the broader harvesting data needs discussion. ~his report is not publicly available, but is available to EPRI member utilit ies.\\

Workshop participants discussed t he criteria proposed by PNNL in the first presentation. One additional criteria suggested by EPRI was to consider fleet-wide vs. plant-specific applicability. More broadly applicable materials would be of greater interest for harvesting than those that represent conditions at only a few plants. Another criteria suggested is the availability of material pedigree Information, such as composition, processing, environmental conditions (temperature, humidity, fluence, etc.). Anot her suggested criteria was t he ease of harvesting. For example, highly irradiated internals are probably 5

Commented 1HA13]: Nice illustration, do you want to call It Figure l with a cross*referencw with the narrative?

Commented [HA14]: Just wondering.. are you able to see this through M OU?

much more difficult and expensive to harvest than electrical cables or unirradiated concrete. This discussion would capture the idea of weighing costs vs. benefits as well as project risk. Further discussion touched on the idea that different organizations may prioritize the various criteria different ly, but all will probably at least want to consider the same set of criteria.

Another key theme from this discussion was that a successful program should be guided by a clearly defined objective or problem statement to be addressed. This objective should be well-understood at the initiation of a program and used to guide decision-making through implementation of a harvesting project. This also raises a related point or potential criteria: the timeliness of the expected research results relative to the objective. If the results are needed in the next two years, but a harvesting project will not provide results for at least five years, that should be a strong consideration.

Session 3! Sources of Materials Session 3 focused on discussing sources of materials for harvesting. This discussion covered previously harvested materials as well as sources for new harvesting programs from operating or decommissioning plants. Both domestic and international sources of materials were discussed in this session.

As shownPreseAtatiaAs weFe ~raviaea in Appendix II, providing presentation t it les. speakers for this session includedlly:

Matthew Hiser from NRC, Al Ahluwalia from EPRI, Tom Rosseel from DOE/ORNL, John Jackson from DOE/Idaho National Laboratory (INL),

Gerry van Noordennen from EnergySolutions, Arzu Alpan from Westinghouse, Uwe Jendrich from GRS, and Daniel Tello from the Canadian Nuclear Safety Commission (CNSC).

Presentation Summaries NRC presented their perspective on sources of materials for harvesting. First, NRC shared some of the harvested materials from past research programs t hat may be available, including irracliat ed stainless stee l internals, RPV materials, nickel alloy welds, neutron absorber material, and electrical components.

NRC then summarized the recently and planned shutdown U.S. plants, including their design, thermal output, and years of operation, to provide participants with an idea of the potential sources from decommissioning U.S. plants. Finally, NRC shared a list of information that would be helpful to acquire from decommissioning plants to determine the value of components for harvesting. This information included plant design information (component location and dimensions), environmental conditions (temperature, fluence, humidity, stress, etc.) and operating history, material pedigree information (fabrication records), and inspection records (for interest in components with known flaws).

The next presentation from EPRI covered harvesting opportunities at decommissioning plants in Korea and Sweden. In Korea, Kori-1 is a Westinghouse 2-loop PWR (sister plant is Kewaunee) that will shut down in 2017 after 40 years of operation. Korea Hydro and Nuclear Power Central Research Institute (KHNP-CRI) is planning a comprehensive research program on long-term materials aging based on 6

Commented [HA 15]: Not clear If you are talking about future or past discussion. Please correct verb tense.

(b )( 4)

(b )(4) harvesting from Kori-1 and is seeking international part icipation in the harvesting effort. KHNP-CRl's plan is focused on metallic components, including RPV, internals, primary system components, steam generator materials. Harvesting is expected to occur in 2024 with testing to follow through 2030.

In Sweden, Vattenfall is currently harvesting in 2017-2018 RPV material from t he decommissioning Barseback BWR units. This work is focused on irradiation embrittlement, Including comparison of surveillance dat a to actual RPV properties, as well as thermal aging embrittlement. In the future, Vattenfall will be shutting down Ringhals 1 and 2 in 2020 and 2019, respectively. Ringhals 1 is a BWR and Ringhals 2 is a Westinghouse 3-loop PWR design. Of particular note, Ringhals 2 has the second oldest replaced Alloy 690 RPV head and steam generators. Other harvesting opportunities at Ringhals include RPV material with a significant surveillance program, thermal aging effects on low alloy steel from the pressurizer, as well as concrete structures. Vattenfall is open to working with partners t hat are interested in joining them for harvesting at Ringhals.

{b )( 4)

The next presentation by DOE/ORNL focused on several harvesting programs that DOE's LWRS program has been involved wit h. DOE has led t he harv*esting of components from the Zion I

• iplant0in the U.S. From Zion, DOE has harvested electrical cables and components, a large RPV section, and a significant numberam&lffit of records to provide information on material fabrication, in-service inspection and operating history. Cables from Zion include CRDM, thermocouple, and low and medium voltage cables. DOE indicated some thermocouple cables from Zion may be available for other researchers to use in collaborative studies.

... {_~ )(4)

,_ ___...., ________________ __. DOE is also participating in efforts to harvest

.... ~ablesfrom*trystal River (led by EPRI) and concrete from the Zorita plant in Spain (led by NRC).

The next presentation by DOE/I NL described I NL's Nuclear Science User Facilities (NSUF) and the Nuclear Fuels and Materials Library (NFML). NSUF is coordinated by INL and facilitates access to nuclear research facilities around t he world, including neutron and ion irradiations, beamlines, hot cell test ing, characterization, and computing capabilities.

[NFML is a Web-based searchable database sample library that captures the information from thousands of specimens available to NSU~. NFML is designed to maximize the benefit of previously irradiated materials for future research. Researchers can propose new research projects under NSUF using specimens in N FML using DOE funding. The information captured in NFML aligns well with t he goal of this session to potentially develop a database of previously harvested materials.

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The next presentation by EnergySolutions offered a more practical perspective on considering sources of materials for harvesting. From the plant owner perspective, in the decommissioning process there is not a financial incent ive to support harvesting, therefore researchers need to absorb costs for harvesting and have a clear scope for harvesting. Flexibility in funding for harvesting activities is essential as t he decommissioning process and schedule may change quickly.

7 Commented [HA16]: Nice illu,tration, maybe c,o.,.

reference as Figure 2 with caption and c.all-out in text.

EnergySolutions provided valuable perspective on the timing in the decommissioning processves for harvesting different components. Harvesting RPV surveillance coupons should take place when the RPV internals are cut and removed. Harvesting RPV materials is only possible from larger RPVs, as smaller RPVs are shipped Intact to the disposal facility, rather than cut into pieces. Spent fuel rack neutron absorber coupons must be harvested eit her before or after dry storage campaign to remove spent fuel from the spent fuel pool. Harvesting actual spent fuel rack neutron absorber material must come after

~

pool is completely empty. Electrical cables and other components from mild environments may be harvested at any time (once temporary power is established and plant power is shut off), while electrical component s from high rad environments will depend on timing of source term removal schedule.

~oncret~ cores are best harvested when other cores are being taken for site characteri.zation to develop the license Termination Plan. Highly Irradiated concrete from biological shield wall would need to come later in decommissioning after RPV is removed.

In terms of upcoming decommissioning plant s, EnergySolutions indicated that San Onofre and Vermont Yankee will be entering DECON is 2018 and 2019, respectively. Kewaunee, Crystal River, and Fort Calhoun also may enter DECON in next 2 years. If researchers are interested in harvestrng from any of these plants, they should be reaching out to plant owners immediately to begin planning and coordination.

Westinghouse followed their presentation in ~session 2 by describing an opportunity to harvest concrete from the Mlhama 1 plant in Japan. Westinghouse installed and analyzed additional neutron dosimetry in the reactor cavity for one cycle, which were used to validate the radiation transport calculations. Mlhama was shut down in 2015 and is in contact with Westinghouse about the possibility of extracting concrete cores from the biological shield wall. Westinghouse is seeking partners interested in joining this harvesting effort.

The next presentation by GRS covered opportunities for harvesting from German plants. Regulations in Germany require plants to either immediately dismantle or dismantle after a period of safe enclosure, which is largely consistent with options in the U.S. GRS detailed the status of German commercial reactors, which are predominantly BWR and PWR designs. Seventeen reactors are currently undergoing decommissioning, while seven more are currently shutdown and await a decommissioning license. Eight reactors are still operating with scheduled shutdown dates between 2017 and 2022. German RPVs t end to have lower fluence thant U.S. designs due to a larger water gap in the downcomer region. Germany has limited experience wit h harvesting from decommissioning plants. One question that GRS will follow-up on is the "rumored" cable surveillance programs that may be used in Germany and could provide experience and lessons learned for other countries.

The final presentation in Session 3 was by CN5C on harvesting opportunities in Canada. Atomic Energy Canada Limited (AECL) has harvested seven concrete cores from the 20 MW Nuclear Power Demonstration Plant (NPD), which shutdown in 1988 after 25 years of operation. CNSC and AECL are also considering opportunities to harvest concrete from other decommissioned reactors in Canada such as Gentilly-2, Douglas Point, and Whiteshell Reactor 1. In addition to concrete, CNSC arnd AECL are currently harvesting electrical cables from the 675 MWe CANDU-6 Gentilly-2 reactor, which shutdown in 2012 after 29 years of operation. The purpose of this work is t o study cable degradation from thermal aging and radiation damage and validate environmental qualification of the cables. CN5C described 8

Commented [HA17]: "mild environment" above - do you want to say something like "benign" environment or define further?

some of the challenges with t his harvesting effort, such as working wit h plant owners, records, accessibility and contamination of the materials and budgeting with unexpected delays in harvesting.

A future harvesting opportunity Is from the National Research Universal (NRU) reactor at Chalk River, which will shut down in 2018 after operating since 1957. AECL is currently taking an inventory of irradiated materials that can be harvested from NRU in decommissioning. Potential materials for harvesting include metals (steels, nickel alloys, zirconium, aluminum), concret e, graphite, active equipment (pumps, etc.), graphite seals, electrical cables, and thermocouples.

Discussion Summary Following t he presentations, there was some discussion of lessons learned from DOE's Zion harvesting effort. DOE worked with a former senior reactor operator at Zion to identify and acquire the appropriate records from Zion for the components being harvested. DOE also described their flexible approach to acquiring RPV samples by sending a large chun k of material (weighing ~90 tons) to EnergySolut ions' facility in Tennessee, where smaller pieces (weighing ~soo pounds) were cut to send to ORNL. Most of the decontamination was performed at Zion, w it h minimal additional cleaning (as well as cladding removal) taking place at EnergySolut ions' facility.

There was also discussion of acquiring materials from sources other than commercial nuclear facilities.

DOE has considered harvesting concrete from other DOE nuclear facilities, but determined that there were compositional differences between the DOE facilities and commercial facilities that would make them not useful. DOE/I NL ment ioned that the Advanced Test Reactor (ATR) replaces their core internals every ten years. The ATR internals are composed primarily of 347 stainless steel and achieve very high fluence levels after ten years of service.

Another key discussion topic was the possibility of developing a database for previously harvested materials or t hose available for future harvesting. DOE/I NL indicated that their NSUF sample library may be a good starting point for such a database, although any materials In t hat library should be freely available for use in the research community. CNSC and NRC also expressed interested in working to develop a harvesting database.

Session 4!..-Harvesting Experience: Lessons Learned and Practical Aspects Session 4 focused on lessons learned and practical aspects of harvesting. Presenters shared their experience with past harvesting programs, particularly common pitfalls to avoid and successful strat egies to overcome them. Presentations also covered the practical aspects of harvesting from the plant owner and decommissioning company perspective.

As shownPreseAtatiaRs were f!ra*;i!leel in Appendix II, providing presentation t it les. speakers for this session includedby:

Jean Smith from EPRI, Tom Rosseel from DOE/ORNL, Matthew Hiser from NRC, Taku Arai from CRIEPI, Gerry van Noordennen from EnergySolutions, and Bill Zipp from Dominion.

9

[ Commented [HA18]: Also PNNL is interested....

Presentation Summaries EPRI presented their experience and lessons learned from past harvesting programs, particularly harvesting reactor internals and concrete from Zorita and electrical cables from Crystal River. From the Zorita reactor internals experience, EPRI emphasized that harvesting projects take significant t ime, encounter both material retrieval and on-site challenges, and shipping issues. In terms of time, the Zorita Internals Research Project (ZIRPl took about 10 years to go from initial planning to final results, which included about 5 years of project Zorita Internals Research Project Timeline planning, 2 years for material extraction (on-site logistics and shipping), and 3-4 years for testing. EPRl's experience was that decommissioning activities were the top priority and that harvestinR ~$ secondary,wel'E subject to schedule and logistical challenges r __....,._

based on t he changing decommissioning schedule. Shipping issues were also challengirng due to sending activated materials (which were classified as "waste") across international borders, from the reactor in Spain to the testing facility in Sweden. Currently, f~urther planned shipment s of t he Zorit a materials beyond the initial program continue to be impacted by export license challenges in Sweden. More positively, EPRI emphasized that the Zorita reactor internals materials harvesting showed excellent cooperation among many organizations and are.LJ.Q.ll! providing valuable technical information to numerous research projects.

Lessons learned from the Zorita concrete harvesting focused on the challenges with core sample drilling and handling contaminated concrete. Ultimately, an effective core drilling procedure was identified, but required some trial and error. Lessons learned from t he Crystal River cable harvesting included material concerns, the need for on-site support, and cost. In terms of material concerns, radiation and asbestos contamination created addit ional challenges for harvesting. On-site support and the ability to visit the site are extremely valuable to ensure clear communication, retrieval or records for material pedigree information, and awareness of on-site developments in the decommissioning process. Cable harvesting at Crystal River was more expensive than anticipated, particularly in terms of EPRI project management time to coordinate the harvesting activities and engineering support at the plant.

DOE presented lessons learned primarily from the experience harvesting RPV materials and electrical cables and components from the Zion plant. In terms of planning and decision-making, DOE had several lessons learned. DOE hosted a workshop at Zion in 2011 to discuss long-term goals and objectives, which proved very helpful in setting priorities and developing partnerships with other organiz.ations.

Partnerships were very valuable to DOE's harvesting efforts, allowing for leveraging resources and collaboration and sharing results. There are limited opportunities for harvesting key components, so DOE emphasized that participants should take full advantage of the opportunities that arise, understanding that there is a necessary compromise between the materials available and their value in terms of fluence or exposure to aging conditions. Another consideration is the quantity of material harvested, which should be sufficient for the objectives of the planned research as well as any collaborations or partnerships, but limited to control costs.

For implementing the harvesting program, DOE found that flexibility was paramount to be able !Q_adjust scope and plans in response to schedule changes and other development s, while remaining within cost 10 Commented [HA19]: Please Include Figure 3 caption and cross reference in narrative.

I (b )( 4) constraints. Working with a former reactor operator was extremely valuable to benefit from their in-depth knowledge of all parts of the plant, in particular the records for materials pedigree information.

Regular site visits and contacts were also essential to stay aware of the lat est developments in the harvesting planning and decommissioning process, with the understanding that harvesting Is not t he top priority for the decommissioning company. Other important considerations were hazardous materials handling, transportation, and disposal and logistics, including contracts, liability, shipping and disposal.

Finally, DOE's experience is t hat the total costs of a harvesting program from planning tro execution to testing are very high, so they should be carefully weighed against the value of the expected data to be generated.

NRC presented their experience, including benefits from previous harvesting programs, and technical and logistical lessons learned from harvesting. As an organization, NRC has extensive experience with testing harvested materials, including RPV, primary system components, reactor internals, neutron absorbers, concrete and electrical components. NRC's experience is more limited than DOE or EPRI in terms of managing the logistics of a harvesting effort from a decommissioning plant. NRC has generally participated in a secondary role in cooperative efforts or received failed components from operating plants for research. NRC has found that previous harvest ing efforts have been effective in reducing unnecessary conservatism, understanding in-service flaws more realistically for NOE and leak rate methodologies, as well as identifying and better understanding safety issues.

For technical lessons learned, NRC's perspective is that harvesting can provide highly representative aged materials for research, which may be the only practical source of such materials. Harvested materials can be effectively used to validate models or a larger data set from accelerated aging tests. It is important !Q_understand as much as possible about the materials and their in-service environment-ifl seNiee and how this compares with the operating fleet of reactors before committing to a specific harvesting project. For logistical lessons learned, harvesting is expensive and time-consuming, so a sign ificanthlgh technical benefit is needed to ensure the program provides values. Leveraging resources with other organizations can help minimize costs, but can also introduce challenges for aligning priorities and interests of multiple organizations. Finally, transporting irradiated materials, particularly between countries, ~ challenging and time-consuming and should be avoided if at all possible.

CRIEPI presented t heir research experience with harvest ed materials as well as ongoing harvest ing from the Hamaoka 1 plant. The first research program involved atom probe tomography (APT) on RPV surveillance materials. CRIEPI found a correlation between t he volume fraction of Ni-Si-Mn clusters and the change in nil-ductility temperature. In the second research project, CRIEPI characterized the weld and base materials harvested from Greifswald Unit 4 RPV with small-angle neutron scattering, APT, and hardness testing. In the third research project, CRIEPI performed APT on 304L stainless steel reactor internals harvested from control rod and top guide components from 3*13 dpa. Results showed a strong increase in Ni-Si clusters with increasing fluence, but little variation in Al enriched clusters with increasing fluence.

For future work, CRIEPI is collaborating with t he DOE LWRS to investigate RPV materials harvest ed from Zion,_ __..._=---------------'CRIEPI also presented activities underway by Chubu

. *tiectric Power to harvest RPV and concrete samples from the Hamaoka 1 plant. Hamaoka 1 is a 540 MW BWR-4 that operated for 33 years. Harvesting began in 2015 and will continue through 2018.

11

The final two presentations of Session 4 provided the non-researcher perspective from a decommissioning company and plant owner. EnergySolutions, which Is decommissioning the Zion nuclear plant among other facilities, presented the decommissioning process and their experience and lessons learned from harvesting at Zion. As mentioned previously, surgical harvesting Is not the top priority for decommissioning, so researchers must recognize this and coordinate close with the decommissioning company. EnergySolutions emphasized the need to gain senior management support at the plant as well as to expect that there may be staff turnover during a multi-year harvesting effort.

Changes in scope and schedule (originating from either sidelleth sides) can cause frustration on both sides. Early planning and delays with contracting are important to avoid lost opportunities. Being on-site during harvesting is essential to a good outcome.

At Zion, EnergySolutions worked with DOE to harvest RPV materials, cables, electrical components, and spent fuel storage racks. DOE hoped to harvest a particular RPV surveillance capsule, but was unable to, due to the inability !Q.identify the correct capsule. There were also challenges w it h harvesting RPV materials. The cut line on the Unit 2 RPV was too close to the weld to be used for research; fortunately, a successful specimen was harvested from Unit 1. For cabling, the init ial plan was to harvest from 11 different locations, but ultimately due to unforeseen challenges and poor communication and coordination, only 4 different cable locations were harvested. Harvesting the desired cable length (30 feet) also proved challenging, with only shorter sections recovered. PlaAt FeceFes ~searches of plant records were largely effective at providing material pedigree information for cables. Concrete coring was initially planned to take place at Zion, but not performed due to lack of research interest. The spent fuel storage rack harvesting went smoothly, which was assisted by weekend efforts ovei:-the-weekerul when decommissioning activities were not occurring.

The next presentation from Dominion provided its perspective on harvesting from decommissioning plants, focused on the experience at Kewaunee Power Station. The top priority (beyond safety) in decommissioning is t he preservation and good stewardship of the decommissioning trust fund. Staffing is the largest drain on the trust fund, so at Kewaunee, staff was halved within a few months of shutdown and then halved again, about 16 months after permanent shutdown once offsite emergency response requirements were eliminated. Dominion described the example of harvesting the RPV surveillance capsules at this point at Kewaunee and the significant challenges that would exist. Given the reduced staffing and the current plant state (reactor coolant system drained, pumps retired, crane and radiation monitoring not maintained), It would be much more difficult F1eW-than immediately after shutdown.

Kewaunee considered harvesting the surveillance specimens and estimated a cost of six to seven figures based on all the activities required to enable it at this point, post-shutdown, compared to a much lower cost just after shutdown. Dominion observed that some components, such as cables or electrical components, may be available and relatively easy to harvest at almost any time during decommissioning. However, other components such as highly irradiated internals or RPV may be best harvested either shortly after shutdown when staffing and capabilities on-site are high or wait until active demolition of the reactor, which may be years or decades later.

Dominion also touched on the discussion of records for plant components. Records requirements are limited to those needed for safety. Once the plant shuts down and the range of potential safety concerns decreases, systems are downgradecl to non-safety and the associated records are no longer required to be maintained. For perspective, Kewaunee still has all its records four years since shutdown, but w ill likely not continue this much longer. Dominion closed its presentation with a broader 12

perspective on harvesting, emphasizing the need to clearly define a problem statement and understand what technical and regulatory purpose this harvesting will serve. Early planning focused on achieving the clear objective of the work including scope, schedule, budget and contact with plant is essential to a successful harvesting effort.

Discussion Summary The discussion touched on the top lessons learned from past harvesting efforts, which included defining a clear objective and purpose for harvesting, early engagement with the plant, and site coordination during harvesting, Another suggestion was to get utility management buy-in for the harvesting project by identifying a benefit to the utility. EPRI mentioned that cable harvesting at Crystal River went much more successfully once the utility recognized the potential benefits forJ~bseQl:lent-lieeAse renewal. Similarly, w hen harvesting from an operating plant, lone must~-te recognize ~nd work through the challenges the plant may encounter when restarting operations.

During discussion, the question was raised regarding how it is determined whether harvested materials are waste. The discussion concluded that in the U.S. 10 CFR 37 is t he important conside rat ion. 10 CFR 37 defines when additional security requirements are imposed, based on the quantity and activity of materials to be transported. The definition of material as waste versus research materials is not as critical in the U.S. EnergySolutions indicated t hat their shipments of waste or research material could be handled in the same way in the accordance w ith Department ofTransportation regulations, provided that the limits in 10 CFR 37 were not reached.

Session 5, Future Harvesting Program Planning Session 5 focused on the information needed for informed harvesting decision-making and harvesting program planning. This session feat ured a pre*sent ation by Pradeep Ramuhalli from PNNL, followed by a discussion period covering harvesting program planning and reflection on the 2-day workshop.

Presentation Summary PNNL presented its perspective on t he information needed for informed harvesting decision-making.

First, the purpose of the harvesting effort needs to be defined by identifyl!l,g the technical knowledge gaps to be addressed. Next, a research plan should be developed demonstrating how t he harvested material will be used to address the identified gaps. Finally, the appropriate source of material to address the technical gap must be identified, along with resources to support the effort and plans and timelines to perform the harvesting. The specifics of these plans depend greatly on the source of materials and must be flexible based on changing conditions on the ground.

In assessing the best source of materials, researchers should consider the material, its environment, and its condition. Material information includes fabrication information such as manufacturer, composition, and dimensions as well as information related to installation or construction, such as welding processes and parameters. Environmental information includes temperature, humidity, fluence, flux, stress 13 Commented [HA20]: Global comment - once acronym is defined, use that acronym.

Commented IHA21 ]: Typically in a technical report, don't use the pronoun 'you'.

(service, residual, installation), and coolant chemist ry. Component condition informat ion includes inspection history, such as identified flaws or degradation.

Discussion Summary The discussion in Session 5 focused on t he best practical approach to plan future harvesting programs.

There was clear agreement that this approach must begin wit h ident ifying t he data needs best addressed by harvesting, whether from operaiting or decommissioning plants. Once a specific need is identified, t he next step is to find a source t o acquire t he materials of interest as well as other organizations Interested in participating in the harvesting effort.

Key Takeaways from Workshop Session 1 The clear takeaway from the discussion in ~session 1 was that harvesting requires significant resources to be done successfully; therefore it is paramount to ident ify how the planned harvesting will clearly address a significant need to ensure the harvesting project provides strong value. In the context of need for data, EPRI suggested t he goal of harvesting to support research for operation out to 80 years is not a full comprehensive understanding of all aspects of the degradation, but rather a snapshot to confirm other lab results and models. This is an important point for all organizations and researchers to keep in mind before investing significant resources in harvesting.

Session 2 The criteria proposed by PNNL are a good st arting point for prioritizing issues to address by harvesting.

Three additional important criteria would be:

Fleet-wide vs. plant-specific applicability of dat a, Ease of harvesting (in terms of cost and project risk), and Timeliness of the expected research result s relative t o t he objective.

Once a potential harvesting project has reached the point of looking at different sources of materials, the availability of material pedigree information, such as composition, processing, environmental conditions (temperature, humidity, fluence, etc.) is very important to the overall value of harvesting from that particular plant.

Based on the presentations and discussion in Session 2, there appeared to be two areas where participants hadi#I broad interest in pursuing further harvesting: high fluence reactor internals and irradiated concrete. The common drivers for the interest in these issues Is a lack of representative data at the fluence of interest and significant challenges with acquiring representative data through other means. High fluence reactor internals ha~s been addressed somewhat by-#le Zorita lnterAals ReseareA

~

ZIRPj, but stainless steel materials exposed to higher fluence levels at higher temperatures, where void swelling may become significant, could help validat e DOE and EPRI models and provide further technical basis for PWR internals aging management. Irradiated concrete harvesting is currently being pursued from the Zorita reactor in Spain, w ith international collaborat ion and potent ial testing at the Halden Reactor Project.

14

Other areas with some, but less widespread, interest expressed from workshop participants for new harvesting efforts included RPV materials and electrical cables and components. SCK-CEN and NRC expressed interest in RPV harvesting, and NRC expressed interest in electrical component harvesting.

Session 3 To capture the key takeaways from Session 3 focused on sources of materials, two tables of potential sources of materials are presented below. n ie-fi.-sHable l_covers recent or ongoing harvesting programs, while Table 2 tile 5ec0Rll det ails potential future harvesting opportunities.

Table 1. Ongoing Harvesting Programs Country Plant Design Size Years in Components Organlzatlon(s)

(MWe) operation Canada NPD CANDU 20 25 Concrete AECL Gentilly-2 CANDU-6 6,75 29 Cables Japan Hamaoka 1 BWR-4 540 33 RPV, concrete CRIEPI/Chubu Spain Zorita W 1-loop 160 37 Int ernals, concret e EPRI, NRC Sweden Barseback ABB-II 6,15 28 RPV Vattenfall Zion 1/2 W-4 1040 24/25 RPV, cables, DOE, EPRI, NRC loop neutron absorbers U.S.

Crvstal River 3 B&W 860 36 Cables EPRI (b )( 4)

Table 2. Potential Future Sources for Harvesting Country Plant Design Size Years in Potential Notes (MWe) operation Components Canada NRU Test reactor 135 61 TBD AECL; SD:

MWt 2018 Germany Numerous plants either in decommissioning or shutting down soon. See Appendix Ill.

Japan Mlhama W 2-loop 320 40 Concrete

Kansai, Westinghouse RPV, internals, Korea Kori 1 w 2-loop 576 40 SGs, pressurizer, KHNP, EPRI welds, CASS, Ringhals 1 BWR 883 44 RPV, internals Vattenfall; Sweden Rlnghals 2 W 3-loop 900 44 SGs, pressurizer, SD: 2020 I concrete 2019 Kewaunee w 2-looo 566 39 TBD SD: 2013 SONGS 2/3 CE 2-loop 1070 31/30 TBD SD: 2013 Crystal River 3 B&W 860 36 TBD SD: 2013 Vermont BWR-4/Mk-1 605 42 TBD SD: 2015 U.S.

Yankee Fort Calhoun CE 2-loop 482 43 TBD SD: 2016 Palisades CE 2-loop 805 47 TBD SD: 2018 Pilgrim BWR-3/Mk-1 677 47 TBD SD: 2019 Oyster Creek BWR-2/Mk-1 619 50 TBD SD: 2019 15

Indian Point w 4-loop 1020 /

48/46 TBD SD: 2021 2/3 1040 Diablo Canyon W4-loop 1138/

40 TBD SD: 2024-5 1/2 1118 Non-Advanced 250 commercial; Test Reactor Test reactor MWt so Core internals internals replaced every 10 years In addition to the potential sources of materials presented and discussed in Session 3, another takeaway was the suggestion of developing a database for previously harvested materials or those available for future harvesting. The NSUF sample library may be a good starting point for such a database, with appropriate modifications for the purposes of harvesting efforts.

Session 4 There were several important takeaways from Session 4 that were touched on in multiple presentations and the following discussion~. One key takeaway is that researchers should ident ify a clear purpose and scope for harvesting. Having a clear purpose for harvesting helps to guide lat er decisions that must be mad e to adjust course when t he inevitable changes in schedule or unexpected realit ies at t he plant arise. A related note is that harvesting is not the top priority for decommissioning. Therefore, researchers must have clear objectives and scope for harvesting that can be communicated to t he site.

This understanding should shape assumptions and interactions with the plant owner or decommissioning company as well as planning for costs and schedule.

Another takeaway was the value of strong site coordination, including site visits. Multiple presenters touched on the value of being on-site to talk to staff and see the components to be harvested. Mockups and 3-0 simulations can be valuable to ensure success of the approach or technique used to acquire t he specimen. A related point is working with reactor operators at the plant. Several harvesting efforts worked with former reactor operators and benefited greatly from their experience to find records or det ermine the best method to harvest the desired component. This is a valuable insight that could be effective in future harvesting efforts.

A third key takeaway is early engagement with the plant personnel to express interest in harvesting. This serves to make the plant aware of->;el,lf intere*st in harvesting and get their support to w ork with the harvesting process. The other important benefit of early engagement is to gain as much information as possible about the available materials and components, including t he associated records and material pedigree information.

Session 5 The key t akeaway in ~session 5 was to gather as much information as possible in advance of committing to a specific harvesting project. Ideally, there would be a strong understanding that the material and its aging condit ions clearly align with an identified t echnical data need before committing significant resources t o a harvesting effort.

Action Items and Next Steps 16

The following is a summary of the action items discussed at t he end of the workshop:

1. Sharing workshop slides NRC emailed attendees to ask their comfort with sharing their workshop slides with other organizations and received no objection from any presenters.

_* _ The presentations can be accessed here:

https://d rive.google.com/open ?id=0BS DWMLchSYSXcn pZZOJOSOSSQU U.

For NRC staff, the presentations are archived on the LTO SharePoint site:

ht10*111usion.nrc.aov/res/teamldelcmb/LTO/defauIt.aspx?RootF0Ider=%2Fres%2fteam%2Fde%2Fc mb%2FL TO%2FProqram%20Documenls%2FSlraleglc%20Approach%20for%20Obtainlng%20Mat erial%20and%20Component%20Aqing%20lnfonnation&FolderCTID=0x012000A4119D2C08121A4 CAE71 D67 AEB499BF9&View={A08F45B4-F7E9-4960-9890-37F16055A 16Fl

2.

EPRI indicated that MRP-320 (Product ID: 1022866) on knowledge gaps for irradiated austenitic stainless steel for potential harvest ing from MRP-227 inspect ions is publicly available for a fee.

3. Cable surveillance programs in Germany GRS to inquire with cable colleagues and share any insights.

4. Sources of materials database Potential sources of materials presented in this workshop are summarized in Session 3 summary above and Appendix Ill below.

NRC will be reaching out to PNNL, INL NSUF, CNSC, AECL, and any other organizat ions interested in database development.

5. Prioritized data needs Suggest ion to continue discussions on prioritized data needs within technical areas (RPV, internals, electrical, concrete) through existing coordination groups if possible Focus on identifying specific material/ aging conditions of interest and purpose

/ intended outcome of harvesting Idea to survey participants at the 2017 Environmental Degradation conference John Jackson (INL) is on planning committee

,6.

EPRI report on spent fuel liner boric add transport through concrete NRC will contact EPRI for report if needed.

7. Harvested Materials Research Results Section of workshop summary report (below) devoted to references from harvested materials research.

[References to Previous Harvested Materials Researc~

This section of the workshop summary addresses a quest ion that was raised during the discussion at the workshop regarding what the outcome or benefit of past harvesting efforts have been. Below is a list of

~elected, representative 1references to research results generated from testing of harvest ed mat erials:

17 Commented [HA22]: Should these be In any order?

Chronological? Alphabetical?

Commented [HA23]: These words were added because I think your list was not pretending to be comprehensive.

There was other earlier work done at ANL from samples harvested from the ShipplngPort reactor, for example.

J.R. Hawthorne and A.L. Hiser, Experimental Assessments of Gundremmingen RPV Archive Material for Fluence Rate Effects Studies, NUREG/CR-5201 (MEA-2286), U.S. Nuclear Regulatory Commission, October 1988.

G. J. Schuster, S. R. Doctor, A.F. Pardini, and S.L. Crawford, Characterization of Flows in U.S. Reactor Pressure Vessels: Validation of Flaw Density and Distribution in the Weld Metal of the PVRUF Vessel, NUREG/CR-6471 Volume 2, U.S. Nuclear Regulatory Commission, August 2000.

G. J. Schust er, S. R. Doctor, S.L. Crawford, and A. F. Pardini, Characterization of Flaws in U.S. Reactor Pressure Vessels: Density and Distribution of Flow Indications in the Shoreham Vessel, NIUREG/CR-6471 Volume 3, U.S. Nuclear Regulatory Commission, November 1999.

D.E. McCabe, et al. Evaluation of WF-70 Weld Metal From the Midland Unit 1 Reactor Vessel, NUREG/CR-5736 (ORNL/TM-13748), U.S. Nuclear Regulatory Commission, November 2000.

B. Alexandreanu, O.K. Chopra, and W.J. Shack, Crack Growth Rotes in a PWR Environment of Nickel Alloys from the Davis-Besse and V.C. Summer Power Plants, NUREG/CR-6921 (ANL-05/55), U.S. Nuclear Regulatory Commission, November 2006.

S.E. Cumblidge, et al. Nondestructive and Destructive Examination Studies on Removed-from-Service Control Rod Drive Mechanism Penetrations, N UREG/CR-6996, U.S. Nuclear Regulatory Commission, July

2009, S.E. Cumblidge, et al. Evaluation of Ultrasonic Time-of-Flight Diffraction Data for Selected Control Rod Drive Nozzles from Davis Besse Nuclear Power Plant, PNNL-19362, Pacific Northwest National Laboratory, April 2011.

S,L. Crawford, et al. Ultrasonic Phased Array Assessment of the Interference Fit and Leok Path of the North Anno Unit 2 Control Rod Drive Mechoni:sm Nozzle 63 with Destructive Validation, NUREG/CR-7142 (PNNL-21547), U.S. Nuclear Regulatory Commission, August 2012.

18

Japan Europe Canada us industry EPRI DOE I

NRC

~ ppendix I Workshop Participant~

Name Orll!anization Email Taku Arai CRIEPI arait@crieoi.denken.or.io Sadao Higuchi CRIEPI h iguch i@crieQl.den ken.or. i Q Kazunobu Sakamoto JNRA kazunobu sakamoto@nsr.go.jQ Yasuhiro Chimi JAEA chimi.~asuhiro@jaea.go.jQ Uwe Jendrich GRS Uwe.Jendrichirrs.de Rachid Chaouadi SCK-CEN rachid.chaouadi@sckcen.be Guy Roussel Bel V gu~.roussel@Belv.be Daniel Tello CNSC daniel.t ello@canada.ca Desire Ndomba CNSC desire.ndomba@canada.ca Karen Huynh AECL khu~nh@aecl.ca Gerrv van Noordennen Enere:v Solut ions e:ovannoordennenenere:vsolutions.com Bill Zipp Dominion william.f.ziQQ@dom.com Mark Richter NEI mar@nei.org Arzu Alpan West inghouse a1Qanfa@westinghouse.com Sherrv Bernhoft EPRI sbernhoft@epri.com Robin Dyle EPRI rd~le@eQri.com Jean Smith EPRI jmsmith@eQri.com Al Ahluwalia EPRI kahluwal@eQri.com Tom Rosseel ORNL rosseeltm@ornl.e:ov Rich Reister DOE Richard.Reister@nuclear.energ~.gov Keith Leonard ORNL leonardk@ornl.gov M ikhail A. Sokolov ORNL sokolovm@ornl.gov John Wagner INL john.wagner@inl.gov John Jackson INL john.jackson@inl.gov Pradeep Ramuhalli PNNL PradeeQ.Ramuhalli@Qnnl.gov Pat Purtscher NRC Patrick. Pu rt sch e rt@n re.irov Rob Tregoning NRC Robert.Tregoning@nrc.gov Matt Hiser NRC Matthew.Hiser@nrc.gov M ita Sircar NRC Madhumita.Sircar@nrc.gov Tom Koshy NRC Thomas.Kosh~@nrc.gov Jeff Poehler NRC Jeffre~.Poehler@nrc.gov Allen Hiser NRC Allen.Hiser@nrc.gov Angela Buford NRC Angela.Buford@nrc.gov Mark Kirk NRC Mark.Kirk@nrc.gov Amy Hull NRC Am~.Hull@nrc.gov Pete Ricardella NRC/ACRS Priccardella@Structint.com 19 Commented [HA24]: Does this include the webinar people? If not, maybe you should clarify that these were In-room Participants or some such word. What order are they in? not alphabetical in any way...

Commented [HA25]: Mike Weber gave the keynote speech. Did Frankl or Brian Thomas attend?

Session Time Intro 8:00 1

8:15-8:45 8:45-9:45 9:45-10:00 10:00-10:20 10:20 -

10:30 10:30-10:55 2

10:55-11:20 11:20 -

11:45 11:45 -

12:30 12:30- 2:00 2:00 - 2:10 2:10 - 2:35 2:35 - 2:50 2:50-3:00 3:00-3:15 3

3:15-3:30 3:30-3:45 3:45-4:00 4:00 - 4:15 4:15-5:00 Appendix II Workshop Agenda Tuesday, March 7 Oreanization Soeaker Presentation Title NRC Michael Weber Welcome and Introduction to Workshop Robert Tregoning DOE Rich Reister DOE Perspectives on Material HarvestinR EPRI Sherry Bernhoft EPRI Perspective on Harvesting Projects NRC Robert Tregoning NRC Perspective on Motivation for Harvesting GRS Uwe Jendrich Role of GRS in Decommissioning and LTO CRIEPI Taku Arai CRIEPI Motivations for Harvested Material DISCUSSION BREAK PNNL (for NRC)

Pradeep Ramuhalli Data Needs Best Addressed By Harvesting NRC Matthew Hiser High-Priority Data Needs for Harvesting DOE Keit h Leonard LWRS Program Perspective on the Technical Needs for Harvestine Review of past RPV sampling test programs SCK-CEN Rach id Chaouadi and perspective for long t erm operation Westinghouse Arzu Alpan Importance of Harvesting to Evaluate Radiation Effects on Concrete Prooerties DISCUSSION LUNCH NRC M atthew Hiser Sources of Materials: Past NRC Harvesting and U.S. Decommissioning Plants EPRI Al Ahluwalia Harvesting Plans for Materials Aging Degradation Research in Korea and Sweden DOE/ORNL Tom Rosseel Materials Harvested by the LWRS Program DOE/INL John Jackson NSUF M aterial Samole Librarv Energy Solutions Gerry van Zion Material Harvesting Program Noordennen Potential Harvesting of Concrete from M ihama Westinghouse Arzu Alpan Unit 1 BREAK GRS Uwe Jendrich Plants in Decommissioning in Germany Evaluating Structures, Systems & Components CNSC Daniel Tello from Decommissioned/Decommissioning Nuclear Facilities in Canada DISCUSSION 20

Wednesday, March 8 Session Time Or2anization S0eaker Presentation Title 8:00-8:30 EPRI Jean Smith Lessons Learned: Harvesting and Shipping of Zorita Materials 8:30- 9:00 DOE Tom Rosseel LWRS Program: Harvesting Lessons Learned 9:00 - 9:30 NRC Matthew Hiser NRC Perspective on Harvesting Experience and Lessons Learned 9:30 - 10:00 CRIEPI Taku Arai CRIEPI Research Activities with Harvested 4

Materials 10:00-10:15 BREAK 10:15 - 10:45 Energy Gerry van Zion Harvesting Experience and Lessons Solutions Noordennen Learned 10:45 - 11: 15 Dominion Sill Zipp Kewaunee Insights on Material Harvesting 11:15 -12:00 DISCUSSION 12:00-1:30 LUNCH 1:30-1:45 PNNL (for Pradeep Ramuhalli Technical Information Needed for Informed NRC)

Harvesting Decisions 1:45 - 2:30 DISCUSSION s

2:30 - 3:00 Action Items and Next Steps EPRI Sherry Bernhoft 3:00- 4:00 DOE Rich Reister Closing Thoughts NRC RobertTregoning ALL 21

Appendix Ill Harvesting Opportunities in Germany Past and current decommissioning projects of P ototype or Commercial Reactors Name I Abbrev.

Rheinsberg KKR Compact Natrium Cooled KKN Reactor Multipurpose Research R.

MZFR Obrigheim KWO Neckarwestheim 1 GKN-1 lsar-1 KKl-1 Gundremmingen-A KRB-A Greifswald 1-5 KGR 1-5 Lingen KWL WWER SNR PWR/O2O PWR PWR BWR BWR WWER BWR Power I Oecom.

MW.

started 70 1995 21 1993 57 1987 357 2008 840 2017 912 2017 250 1983 440 1995 268 1985 UC: unconditional clearance UC UC UC UC UC UC RCAKRB-11 UC UC after SE RCA: radiation controlled area, new license NRC Harvesting Workshop, RoclMHe, March 2017. Oecormisslonlng in Germany SE: safe enclosure Past and current decommissioning projects of Prototype or Commercial Reactors Name Strategy Stade KKS PWR 672 2005 UC Research Reactor J0lich AVR HTR 15 1994 UC Thorium High-THTR-HTR 308 1993 SE since 1997 Temperature-Reaktor 300 W0rgassen KWW BWR 670 1997 UC M0lheim-Karlich KMK PWR 1302 2004 UC Hot-Steam Reactor HOR HOR 25 1983 UC since 1998 Grosswelzheim N iederaichbach KKN

[)RR/DP 106 1975 UC since 1994 Test-Reactor Kahl VAK BWR 16 1988 UC since 2010 22

Shut down Commercial Re ctors

• that have no decommissioning license granted yet Name Abbrev.

Reactor type Philippsburg-1 KKP-1 BWR Grafenrheinfeld KKG PWR Biblis-A KWB-A PWR Biblis-8 KWB-8 PWR Unterweser KKU BWR Brunsbuttel KKB BWR Krummel KKK BWR

• Commercial Reactors in operation Name Abbrev.

Reactor type Gundremmingen-8 KRB-11-8 BWR Philippsburg-2 KKP-2 PWR Gundremmingen-C KRB-11-C BWR Grohnde KWG PWR Brokclorf KBR PWR Emsland KKE PWR lsar-2 KKl-2 PWR Neckarwestheim-2 GKN-2 PWR 23 frMiihNM 926 1345 1225 1300 1410 806 1402 Date of application 2013 / 2014 2014 2012 2012 2012 / 2013 2012 / 2014 2015 Anticipated date of final shutdown 1344 31.12.2017 1468 31.12.2019 1344 31.12.2021 1430 31.12.2021 1480 31.12.2021 1406 31.12.2022 1485 31.12.2022 1400 31.12.2022

From:

Hiser, Matthew Sent:

Fri, 12 May 2017 21:23:49 +0000 Note to requester: The attachment is immediately following this email.

To:

Purtscher, Patrick;Tregoning, Robert;Ramuhalli, Pradeep (Pradeep.Ramuhalli@pnnl.gov)

Subject:

Workshop Summary Report Attachments:

Harvesting Workshop Summary Report draft 5-12-17.docx Hi Pat, Rob, and Pradeep, I'd like to share with you a largely complete initial draft of the harvesting workshop summary report. I tried to capture the important points of the presentations and discussion at the workshop and then synthesize that down to "key takeaways" (I am open to a better term, but that's what I came up with). I still need to fill in the section on "References to Past Harvested Materials Research", but otherwise consider this a complete draft.

Please feel free to review and comment the overall organization, level of detail, etc. You can also review the specific wording with edits and tracked changes if you'd like, although I'd suggest not spending too much effort down in the weeds at this point.

My hope is to get some feedback in the next 2 weeks from this group and then share with the broader group of workshop attendees by the end of May for their review and input with a target to finalize this report by the end of June.

Thanks and please let me know if you have any questions!

Matt

Harvesting Workshop Summary Report

Background

On March 7-8, 2017, the Office of Nuclear Regulatory Research of the United States Nuclear Regulatory Commission (NRC) hosted a 2-day workshop on the topic of "Ex-Plant Materials Harvesting." NRC staff worked in close coordination with staff from the U.S. Department of Energy (DOE) and the Electric Power Research Institute (EPRI) to plan and arrange the workshop.

The decision to organize this workshop was driven by developments in the U.S. and global nuclear industry. In the U.S., there is strong interest in extending plant lifespans through subsequent license renewal (SLR) from 60 to 80 years. Extended plant operation and SLR raise a number of technical issues that may require further research to understand aging mechanisms, which may benefit from harvesting.

Meanwhile, in recent years, a number of nuclear plants, both in the U.S. and internationally, have shut down or announced plans to shut down. Unlike in the past when there were very few plants shutting down, these new developments provide opportunities for harvesting components that were aged in representative light water reactor (LWR) environments. In a related development, economic challenges for the nuclear industry and limited government spending have limited the resources available to support new research, including harvesting programs. Given this constrained budget environment, aligning interests and leveraging with other organizations is important to allow maximum benefit and value for future research programs.

Objective and Approach The objective of the workshop was to generate open discussion of all aspects of ex-plant materials harvesting, including:

1.

Deciding whether to harvest,

2.

Planning and implementing a harvesting program,

3.

Using the harvested materials in research programs.

Through presentations and open discussion, the workshop was organized to allow for all participants to be better informed of the benefits and challenges of harvesting as well as to identify potential areas of common interest for future harvesting programs. Workshop sessions were aligned in broad topics to cover all aspects of harvesting, but allow for participants to drive the discussion.

To help accomplish the workshop objectives, the workshop organizers intentionally sought a diverse group of participants. There are a large number of decommissioning plants and interested researchers outside the U.S., so the organizers focused on outreach to international participants through connections such as IAEA, OECD/NEA, and existing professional contacts. In addition, a key goal for this workshop was to capture the broader practical perspective from plant owners and decommissioning companies, which are vital to any successful harvesting program, but may sometimes be overlooked in researcher-driven discussions. Workshop participants were also diverse in terms of technical area of focus, with metal components such as the reactor pressure vessel (RPV) and internals being discussed along with concrete and electrical components. The final list of workshop participants can be found at the end of this report in Appendix I.

1

Workshop Organization and Sessions The workshop was held at NRC headquarters in Rockville, MD. Due to limited space in the meeting room and the need for a limited group size for discussion, a webinar was used to allow remote observers to benefit from the workshop. Workshop sessions were organized topically with about half the time dedicated to presentations and the remaining time set aside for discussion. Presentations were solicit ed from participants to cover a range of perspectives and technical areas. The final workshop agenda can be found at the end of this summary report in Appendix II.

The workshop was organized into five sessions as follows:

Session 1 Motivation for Harvesting Session 2 Technical Data Needs for Harvesting Session 3 Sources of Mate rials Session 4 Harvesting Experience: Lessons Learned and Practical Aspects Session 5 Future Harvesting Program Planning Summary of Workshop Discussion The subsections below will summarize the presentations and discussion in each session and highlight the key takeaways from the session.

Session 1 Motivation for Harvesting Session 1 focused on the motivation for harvesting and why workshop participants are interested in harvesting. Presentations were provided in this session by:

Richard Reister from DOE, Sherry Bernhoft from EPRI, Robert Tregoning from NRC, Uwe Jendrich from the Gesellschaft fur Anlagen-und Reaktorsicherheit (GRS) in Germany, and Taku Arai from the Central Research Institute of the Electric Power Industry (CRIEPI) in Japan.

Presentation Summaries DOE described the role of harvesting within the Light Water Reactor Sustainability (LWRS) Program, including the benefits and challenges associated with harvesting. Benefits include t he opportunity to fill knowledge gaps where there is limited data or experience and to inform degradation models wit h data from actual plant components. Challenges include cost, complexity, scheduling, logistics, limited opportunities, acquiring sufficient material pedigree information, and potent ial negative resullts impacting operating plants.

EPRI discussed the role of harvesting within the context of aging management for Long-Term Operations (LTO), including their experience from past harvesting programs and criteria for future harvest ing. Their experience emphasized the challenges of cost, schedule, logistics, complicated contracting and acquiring material pedigree information. EPRl's criteria for harvesting include value to their members that addresses a prioritized need and knowledge gap that cannot be otherwise filled through other means.

2

For EPRI, a well-developed project plan that covers funding, risk management, exit ramps, and clear roles and responsibilities is essential.

NRC shared its perspective on the benefits and challenges of harvesting in regulatory research.

Harvested materials are valuable due to the representative nature of their aging conditions, which may reduce the uncertainty associated with the applicability of the results to operating plants compared to tests with alternative aging conditions. Harvested materials may be the best option to address technical data needs identified for extended plant operation. Increasing harvesting opportunities from decommissioning plants suggests a proactive approach to harvesting planning may optimize benefits by identifying the appropriate material with the aging conditions of interest for the identified knowledge gap. There are significant challenges associated with harvesting, including cost, schedule, and logistics, but hopefully these can be mitigated or avoided by leveraging with other organizations and learning from past experience.

GRS described its role as the main technical support organization in nuclear safety for the German federal government. GRS provides technical assessment and knowledge transfer for decommissioning activities, aging management, and long-term operation for German federal and international organizations.

CRIEPI discussed its view of how harvested materials and laboratory prepared materials contribute to addressing technical issues. Harvested materials provide exposure to actual plant conditions, but are more limited in availability and the size of the data set that can be generated. Laboratory prepared materials general involve accelerated or simulated aging conditions, but can be used to produce larger data sets and varying parameters can allow understanding of the effect on the mechanism or property of interest. Harvested materials offer fact finding of actual plant conditions as well as confirmation and verification of results from laboratory prepared specimens.

Discussion Summary The discussion following the presentations in this session focused on clearly identifying the need to be addressed by a harvesting project and the myriad cost, scheduile, and logistical challenges associated with harvesting. Leveraging with other organizations to defray costs can also help improve the value of a given program, but also adds complexity as another organization may have a different set of priorities that changes the focus of the harvesting effort.

Session 2 Technical Data Needs for Harvesting Session 2 focused on discussing the technical data needs for harvesting and what specific knowledge gaps organizations are interested in addressing through harvesting. This discussion included general perspectives on how to determine when harvesting should be pursued rather than other types of research. Presentations were provided in this session by:

Pradeep Ramuhalli from the Pacific Northwest National Lab (PNNL),

Matthew Hiser from NRC, Keith Leonard from Oak Ridge National Laboratory (ORNL),

Rachid Chaouadi from SCK-CEN in Belgium, and Arzu Alpan from Westinghouse.

3

Presentation Summaries PNNL presented their work, under a small NRC contract, to develop a systematic approach to prioritize data needs for harvesting. PNNL proposed five primary criteria for prioritizing harvesting:

Unique field aspects of degradation o

For example, unusual operating experience or legacy materials (composition, etc.) that be no longer available Ease of laboratory replication of environment-materia I combination o

For example, simultaneous thermal and irradiation conditions may be difficult to replicate or mechanism sensitive to dose rate may not be good for accelerated aging Applicability of harvested material for addressing critical gaps o

Prioritize harvesting for critical gaps over less essential data needs Availability of reliable in-service inspection (ISi) techniques for the material/ component o

If inspection methods are mature and easy to apply to monitor and track degradation, perhaps the effort of research with harvested materials is not needed.

Availability of material for harvesting o

The necessary materials/ components must be available to be harvested.

PNNL then presented their application of these criteria to four materials degradation issues as an example: electrical cables, cast austenitic stainless steel (CASS), reactor vessel internals, and dissimilar metal welds. Based on applying these criteria to the examples, PNNL concludes that electrical cables, CASS, and reactor internals are all higher priority for harvesting due to unique aspects of the degradation that are challenging to replicate in the lab. Meanwhile, dissimilar metal welds are of low priority due to the ease of replication in lab aging studies as well as the significant body of knowledge and research on the phenomena.

NRC presented a summary of data needs it is interested in pursuing through harvesting. These included RPV materials to validate fluence and attenuation models and to demonstrate the conservatism of regulatory approaches for transition temperature prediction. Other metal components of interest for harvesting would address data gaps in irradiated stainless steels, as well as improve understanding of inspection capabilities and fatigue life calculations. Electrical components of interest include low and medium voltage cables and other electrical components for degradation studies, and electrical enclosures and cables for fire research. Concrete components of interest include irradiated concrete, concrete undergoing alkali-aggregate reactions, post-tensioned structures, reinforcing steel, tendons, and spent fuel pool concrete to assess potential boric acid attack.

DOE/ORNL presented their perspective on data needs for harvesting and its role in providing validation of experimental and theoretical research. DOE performed a significant reactor pressure vessel (RPV) harvesting program at the Zion nuclear power plant to reduce uncertainties in the Master Curve methodology, validate modeling predictions and study flux and fluence attenuation effects. The harvesting is largely complete, but the testing program is currently underway. DOE also indicated interest in using harvested materials to validate its models for swelling and microstructural changes of stainless steel internals under LWR irradiation conditions. Harvesting concrete components would be of interest due to lack of literature data and the multiple dependent variables that may affect concrete 4

performance. Finally, DOE has been involved in harvesting cables from the Crystal River and Zion plants to address cable aging as a function of material composition and environment.

SCK-CEN presented their interest in a international cooperative program to harvest reactor pressure vessel (RPV) materials. SCK-CEN presented their survey of the literature for past testing programs of harvested RPV materials, and tlhe limitations of these past program. Key limitations include a lack of archive materials, generally lower temperatures, and poor surveillance programs and dosimetry. SCK-CEN then shared some thoughts on their criteria for a new harvesting efforts, including higher fluence levels and temperatures, available archive materials and reliable information on operating history, dosimetry and surveillance program. Other topics relevant to a new RPV harvesting effort include technical issues such as material variability and irradiation conditions as well as logistical and financial considerations.

The final presentation in Session 2 by Westinghouse focused on the need for harvesting irradiated concrete to better understand the threshold radiation level for significant strength reduction.

Westinghouse has installed ex-vessel neutron dosimetry (EVND) at a number of plants in the world and proposed to use these dosimetry measurements to validate fluence model calculations to better understand the uncertainty in these calculations. If concrete can be harvested at one of these plants with EVND data, then irradiated concrete properties from testing can be paired with fluence data to improve research benefits.

Discussion Summary Dosimetry capsules Westingflouse Dosimetry chain IJ The discussion following Session 2 presentations touched on a number of topics. EPRI shared that they developed a report related to the topics of session 2, but more narrowly focused on PWR internals.

MRP-320, "Testing Gap Assessment and Material Identification for PWR Internals," focuses on prioritizing opportunistic harvesting of stainless steel reactor internals components that may be removed from service following MRP-227 inspections. The methodology and approach in this report may be relevant to the broader harvesting data needs discussion. This report is not publicly available, but is available to EPRI member utilities.

Workshop participants discussed the criteria proposed by PNNL in the first presentation. One additional criteria suggested by EPRI was to consider fleet-wide vs. plant-specific applicability. More broadly applicable materials would be of greater interest for harvesting than those that represent conditions at only a few plants. Another criteria suggested is the availability of material pedigree information, such as composition, processing, environmental conditions (temperature, humidity, fluence, etc.). Another suggested criteria was the ease of harvesting. For example, highly irradiated internals are probably much more difficult and expensive to harvest than electrical cables or unirradiated concrete. This discussion would capture the idea of weighing costs vs. benefits as well as project risk. Further discussion touched on the idea that different organizations may prioritize the various criteria differently, but all will probably at least want to consider the same set of criteria.

5

Another key theme from this discussion was that a successful program should be guided by a clearly defined objective or problem statement to be addressed. This objective should be well-understood at the initiation of a program and used to guide decision-making through implementation of a harvesting project. This also raises a related point or potential criteria: the timeliness of the expected research results relative to the objective. If the results are needed in the next two years, but a harvesting project will not provide results for at least five years, that should be a strong consideration.

Session 3 Sources of Materials Session 3 focused on discussing sources of materials for harvesting. This discussion covered previously harvested materials as well as sources for new harvesting programs from operating or decommissioning plants. Both domestic and international sources of materials were discussed in this session.

Presentations were provided in this session by:

Matthew Hiser from NRC, Al Ahluwalia from EPRI, Tom Rosseel from DOE/ORNL, John Jackson from DOE/Idaho National Laboratory (INL),

Gerry van Noordennen from EnergySolutions, Arzu Alpan from Westinghouse, Uwe Jendrich from GRS, and Daniel Tello from the Canadian Nuclear Safety Commission (CNSC).

Presentation Summaries NRC presented their perspective on sources of materials for harvesting. First, NRC shared some of the harvested materials from past research programs that may be available, including irradiated stainless steel internals, RPV materials, nickel alloy welds, neutron absorber material, and electrical components.

NRC then summarized the recently and planned shutdown U.S. plants, including their design, thermal output, and years of operation, to provide participants with an idea of the potential sources from decommissioning U.S. plants. Finally, NRC shared a list of information that would be helpful to acquire from decommissioning plants to determine the value of components for harvesting. This information included plant design information (component location and dimensions), environmental conditions (temperature, fluence, humidity, stress, etc.) and operating history, material pedigree information (fabrication records), and inspection records (for interest in components with known flaws).

The next presentation from EPRI covered harvesting opportunities at decommissioning plants in Korea and Sweden. In Korea, Kori-1 is a Westinghouse 2-loop PWR (sister plant is Kewaunee) that wiill shut down in 2017 after 40 years of operation. Korea Hydro and Nuclear Power Central Research Institute (KHNP-CRI) is planning a comprehensive research program on long-term materials aging based on harvesting from Kori-1 and is seeking international participation in the harvesting effort. KHNP-CRl's plan is focused on metallic components, including RPV, internals, primary system components, steam generator materials. Harvesting is expected to occur in 2024 with testing to follow through 2030.

In Sweden, Vattenfall is currently harvesting in 2017-2018 RPV material from the decommissioning Barseback BWR units. This work is focused on irradiation embrittlement, including comparison of 6

surveillance data to actual RPV properties, as well as thermal aging embrittlement. In the future, Vattenfall will be shutting down Ringhals 1 and 2 in 2020 and 2019, respectively. Ringhals 1 is a BWR and Ringhals 2 is a Westinghouse 3-loop PWR design. Of particular note, Ringhals 2 has the second oldest replaced Alloy 690 RPV head and steam generators. Other harvesting opportunities at Ringhalls include RPV material with a significant surveillance program, thermal aging effects on low alloy steel from the pressurizer, as well as concrete structures. Vattenfall is open to working with partners that are interested in joining them for harvesting at Ringhals.

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The next presentation by DOE/ORNL focused on several harvesting programs that DOE's L\\NRS program has been involved with. DOE has led the harvesting of components from the Zion I

• !Plan1(]in... (p){4) the U.S. From Zion, DOE has harvested electrical cables and components, a large RPV section, and a significant amount of records to provide information on material fabrication, in-service inspection and operating history. Cables from Zion include CROM, thermocouple, and low and medium voltage cables.

DOE indicated some thermocouple cables from Zion may be available for other researchers to use in collaborative studies.

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River (led by EPRI) and concrete from the Zorita plant in Spain (led by NRC).

The next presentation by DOE/I NL described IN L's Nuclear Science User Facilities (NSUF) and the Nuclear Fuels and Materials Library (NFML). NSUF is coordinated by INL and facilitates access to nuclear research facilities around the world, including neutron and ion irradiations, beamlines, hot cell testing, characterization and computing capabilities.

NFML is a Web-based searchable database sample library that captures the information from thousands of specimens available to NSUF. NFML is designed to maximize the benefit of previously irradiated materials for future research. Researchers can propose new research projects under NSUF using specimens in NFML using DOE funding. The information captured in NFML aligns well with the goal of this session to potentially develop a database of previously harvested materials.

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..J The next presentation by EnergySolutions offered a more practical perspective on considering sources of materials for harvesting. From the plant owner perspective, in the decommissioning process there is not a financial incentive to support harvesting, therefore researchers need to absorb costs for harvesting and have a clear scope for harvesting. Flexibility in funding for harvesting activities is essential as the decommissioning process and schedule may change quickly.

EnergySolutions provided valuable perspective on the timing in the decommissioning proves for harvesting different components. Harvesting RPV surveillance coupons should take place when the RPV internals are cut and removed. Harvesting RPV materials is only possible from larger RPVs, as smaller RPVs are shipped intact to the disposal facility, rather than cut into pieces. Spent fuel rack neutron absorber coupons must be harvested either before or after dry storage campaign to remove spent fuel 7

from spent fuel pool. Harvesting actual spent fuel rack neutron absorber material must come after pool is completely empty. Electrical cables and other components from mild environments may be harvested at any time (once temporary power is established and plant power is shut off), while electrical components from high rad environments will depend on timing of source term removal schedule.

Concrete cores are best harvested when other cores are being taken for site characterization to develop the License Termination Plan. Highly irradiated concrete from !biological shield wall would need to come later in decommissioning after RPV is removed.

In terms of upcoming decommissioning plants, EnergySolutions indicated that San Onofre and Vermont Yankee will be entering DECON is 2018 and 2019, respectively. Kewaunee, Crystal River, and Fort Calhoun also may enter DECON in next 2 years. If researchers are interested in harvesting from any of these plants, they should be reaching out to plant owners immediately to begin planning and coordination.

Westinghouse followed their presentation in session 2 by describing an opportunity to harvest concrete from the Mihama 1 plant in Japan. Westinghouse installed and analyzed additional neutron dosimetry in the reactor cavity for one cycle, which were used to validate the radiation transport calculations.

Mihama was shutdown in 2015 and is in contact with Westinghouse about the possibility of extracting concrete cores from the biological shield wall. Westinghouse is seeking partners interested in joining this harvesting effort.

The next presentation by GRS covered opportunities for harvesting from German plants. Regulations in Germany require plants to either immediately dismantle or dismantle after a period of safe enclosure, which is largely consistent with options in the U.S. GRS detailed the status of German commercial reactors, which are predominantly BWR and PWR designs. Seventeen reactors are currently undergoing decommissioning, while seven more are currently shutdown and await a decommissioning license. Eight reactors are still operating with scheduled shutdown dates bet ween 2017 and 2022. German RPVs tend to have lower fluence that U.S. designs due to a larger water gap in the downcomer region. Germany has limited experience with harvesting from decommissioning plants. One question that GRS will follow-up on is the "rumored" cable surveillance programs that may be used in Germany and could provide experience and lessons learned for other countries.

The final presentation in Session 3 was by CNSC on harvesting opportunities in Canada. Atomic Energy Canada Limited (AECL) has harvested seven concrete cores from the 20 MW Nuclear Power Demonstration Plant (NPD), which shutdown in 1988 after 25 years of operation. CNSC and AECL are also considering opportunities to harvest concrete from other decommissioned reactors in Canada such as Gentilly-2, Douglas Point, and Whiteshell Reactor 1. In addition to concrete, CNSC and AECL are currently harvesting electrical cables from the 675 MWe CANDU-6 Gentilly-2 reactor, which shutdown in 2012 after 29 yea rs of operation. The purpose of this work is to study cable degradation from thermal aging and radiation damage and validate environmental qualification of the cables. CNSC described some of the challenges with this harvesting effort, such as working with plant owners, records, accessibility and contamination of the materials and budgeting with unexpected delays in harvesting.

A future harvesting opportunity is from the National Research Universal (NRU) reactor at Chalk River, which will shut down in 2018 after operating since 1957. AECL is currently taking an inventory of irradiated materials that can be harvested from NRU in decommissioning. Potential materials for 8

harvesting include metals (steels, nickel alloys, zirconium, aluminum), concrete, graphite, active equipment (pumps, etc.), graphite seals, electrical cables, and thermocouples.

Discussion Summary Following the presentations, there was some discussion of lessons from DOE's Zion harvesting effort.

DOE worked with a former senior reactor operator at Zion to identify and acquire the appropriate records from Zion for the components being harvested. DOE also described their flexible approach to acquiring RPV samples by sending a large chunk of material (weighing ~go tons) to EnergySolutions' facility in Tennessee, where smaller pieces (weighing ~soo pounds) were cut t o send to ORNL. Most of the decontamination was performed at Zion, with minimal additional cleaning (as well as cladding removal) taking place at EnergySolutions' facility.

There was also discussion of acquiring materials from sources other than commercial nuclear facilities.

DOE has considered harvesting concrete from other DOE nuclear facilities, but determined that there were compositional differences between the DOE facilities and commercial that would make them not useful. DOE/I NL mentioned that the Advanced Test Reactor (ATR) replaces their core internals every ten years. The ATR internals are composed primarily of 347 stainless steel and achieve very high fluence levels after ten years of service.

Another key discussion topic was the possibility of developing a database for previously harvested materials or those available for future harvesting. DOE/I NL indicated that their NSUF sample library may be a good starting point for such a database, although any materials in that library should be freely available for use in the research community. CNSC and NRC also expressed interested in working to develop a harvesting database.

Session 4 Harvesting Experience: Lessons Learned and Practical Aspects Session 4 focused on lessons learned and practical aspects of harvesting. Presenters shared their experience with past harvesting programs, particularly common pitfalls to avoid and successful strategies to overcome them. Presentations also covered the practical aspects of harvesting from the plant owner and decommissioning company perspective.

Presentations were provided in this session by:

Jean Smith from EPRI, Tom Rosseel from DOE/ORNL, Matthew Hiser from NRC, Taku Arai from CRIEPI, Gerry van Noordennen from EnergySolutions, and Bill Zipp from Dominion.

Presentation Summaries EPRI presented their experience and lessons learned from past harvesting programs, particularly harvesting reactor internals and concrete from Zorita and electrical cables from Crystal River. From the Zorita reactor internals experience, EPRI emphasized that harvesting projects take significant time, encounter material retrieval and on-site challenges, and shipping issues. In terms of time, ZIRP took 9

about 10 years to go from initial planning to final results, which included about 5 years of project planning, 2 years for material extraction (on-site logistics and shipping), and 3-4 years for testing. EPRl's experience was decommissioniing activities were the top priority and harvesting were subject to schedule and logistical challenges based on the changing decommissioning schedule. Shipping issues were also challenging due to sending activated materials (which were classified as "waste") across international borders, from the reactor in Spain Zorita Internals Research Project Timeline to testing facility in Sweden. Further planned shipments of the Zorita materials beyond the initial program continue to be impact by export license challenges in Sweden. More positively, EPRI emphasized that the Zorita reactor internals materials harvesting showed excellent "roj,ectln<<poll "1

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cooperation among many organizations and are providing valuable technical information to numerous research projects.

Lessons learned from the Zorita concrete harvesting focused on the challenges with core sample drilling and handling contaminated concrete. Ultimately, an effective core drilling procedure was identified, but required some trial and error. Lessons learned from the Crystail River cable harvesting included material concerns, the need for on-site support, and cost. In terms of material concerns, radiation and asbestos contamination created additional challenges for harvesting. On-site support and the ability to visit the site are extremely valuable to ensure clear communication, retrieval or records for material pedigree information, and awareness of on-site developments in the decommissioning process. Cable harvesting at Crystal River was more expensive than anticipated, particularly in terms of EPRI project management time to coordinate the harvesting activities and engineering support at the plant.

DOE presented lessons learned primarily from the experience harvesting RPV materials and electrical cables and components from the Zion plant. In terms of planning and decision-making, DOE had several lessons learned. DOE hosted a workshop at Zion in 2011 to discuss long-term goals and objectives, which proved very helpful in setting priorities and developing partnerships with other organizations.

Partnerships were very valuable to DOE's harvesting efforts, allowing for leveraging resources and collaboration and sharing results. There are limited opportunities for harvesting key components, so take full advantage of the opportunities that arise, understanding that there is a necessary compromise between the materials available and their value in terms of fluence or exposure to aging conditions.

Another consideration is the quantity of material harvested, which should be sufficient for the objectives of the planned research as well as any collaborations or partnerships, but limited to control costs.

For implementing the harvesting program, DOE found that flexibility was paramount to be ablle adjust scope and plans in response to schedule changes and other developments, while remaining within cost constraints. Working with a former reactor operator was extremely valuable to benefit from t heir in-depth knowledge of all parts of the plant, in particular the records for materials pedigree information.

Regular site visits and contacts were also essential to stay aware of the latest developments in the harvesting planning and decommissioning process, with the understanding that harvesting is not the top priority for decommissioning company. Other important considerations were hazardous materials handling, transportation, and disposal and logistics, including contracts, liability, shipping and disposal.

Finally, DOE's experience is that the total costs of a harvesting program from planning to execution to 10

testing are very high, so they should be carefully weighed against the value of the expected data to be generated.

NRC presented their experience, including benefits from previous harvesting programs, and technical and logistical lessons learned from harvesting. As an organization, NRC has extensive experience with testing harvested materials, including RPV, primary system components, reactor internals, neutron absorbers, concrete and electrical components. NRC's experience is more limited than DOE or EPRI in terms of managing the logistics of a harvesting effort from a decommissioning plant. NRC has generally participated in a secondary role in cooperative efforts or received failed components from operating plants for research. NRC has found that previous harvesting efforts have been effective in reducing unnecessary conservatism, understanding in-service flaws more realistically for NDE and leak rate methodologies, as well as identifying and better understanding safety issues.

For technical lessons learned, NRC's perspective is that harvesting can provide highly representative aged materials for research, which may be the only practical source of such materials. Harvested materials can be effectively used to validate models or a larger data set from accelerated aging tests. It is important understand as much as possible about the materials and their environment in service and how this compares with the operating fleet of reactors before committing to a specific harvesting project. For logistical lessons learned, harvesting is expensive and time-consuming, so a high technical benefit is needed to ensure the program provides values. Leveraging with other organizations can help minimize costs, but can also introduce challenges for aligning priorities and interests of multiple organizations. Finally, transporting irradiated materials, particularly between countries, challenging and time-consuming and should be avoided if at all possible.

CRIEPI presented their research experience with harvested materials as well as ongoing harvesting from the Hamaoka 1 plant. The first research program involved atom probe tomography (APT) on RPV surveillance materials. CRIEPI found a correlation between the volume fraction of Ni-Si-Mn clusters and the change in nil-ductility temperature. In the second research project, CRIEPI characterized t lhe weld and base materials harvested from Greifswald Unit 4 RPV with small-angle neutron scattering, APT, and hardness testing. In the third research project, CRIEPI performed APT on 304L stainless steel reactor internals harvested from control rod and top guide components from 3-13 dpa. Results showed a strong increase in Ni-Si clusters with increasing fluence, but little variation in Al enriched clusters with increasing fluence.

For future work, CRIEPI is collaborating with DOE LWRS to investigate RPV materials harvested from Zion (b)(4)

....... L

!CRIEPI also presented activities underway by Chubu Electric Power to harvest RPV and concrete samples from the IHamaoka 1 plant. Hamaoka 1 is a 540 MW BWR-4 that operated for 33 years. Harvesting began in 2015 and will continue through 2018.

The final two presentations of Session 4 provided the non-researcher perspective from a decommissioning company and plant owner. EnergySolutions, which is decommissioning the Zion nuclear plant among other facilities, presented the decommissioning process and their experience and lessons learned from harvesting at Zion. As mentioned previously, surgical harvesting is not the top priority for decommissioning, so researchers must recognize this and coordinate close with the decommissioning company. EnergySolutions emphasized the need to gain senior management support at the plant as well as to expect that there may be staff turnover during a multi-year harvesting effort.

Changes in scope and schedule (originating from both sides) can cause frustration on both sides. Early 11

planning and delays with contracting are important to avoid lost opportunities. Being on-site during harvesting is essential to a good outcome.

At Zion, EnergySolutions worked with DOE to harvest RPV materials, cables, electrical components, and spent fuel storage racks. DOE hoped to harvest a particular RPV surveillance capsule, but was unable to due to the inability identify the correct capsule. There were also challenges with harvesting RPV materials. The cut line on the Unit 2 RPV was too close to the weld to be used for research; fortunately, a successful specimen was harvested from Unit 1. For cabling, the initial plan was to harvest from 11 different locations, but ultimately due to unforeseen challenges and poor communication and coordination, only 4 different cable locations were harvested. Harvesting the desired cable length (30 feet) also proved challenging, with only shorter sections recovered. Plant records searches were largely effective at providing material pedigree information for cables. Concrete coring was initially pllanned to take place at Zion, but not performed due to lack of research interest. The spent fuel storage rack harvesting went smoothly, which was assisted by efforts over the weekend when decommissioning activities were not occurring.

The next presentation from Dominion provided its perspective on harvesting from decommissioning plants, focused on the experience at Kewaunee Power Station. The top priority (beyond safety) in decommissioning is the preservation and good stewardship of the decommissioning trust fund. Staffing is the largest drain on the trust fund, so at Kewaunee staff was halved within a few months of shutdown and then halved again about 16 months after permanent shutdown once offsite emergency response requirements were eliminated. Dominion described the example of harvesting the RPV surveillance capsules at this point at Kewaunee and the significant challenges that would exist. Given the reduced staffing and the current plant state (reactor coolant system drained, pumps retired, crane and radiation monitoring not maintained), it would be much more difficult now than immediately after shutdown.

Kewaunee considered harvesting the surveillance specimens and estimated a cost of six to seven figures based on all the activities required to enable it at this point po.st-shutdown compared to a much lower cost just after shutdown. Dominion observed that some components, such as cables or electrical components, may be available and relatively easy to harvest at almost any time during decommissioning. However, other components such as highly irradiated internals or RPV may be best harvested either shortly after shutdown when staffing and capabilities on-site are high or wait until active demolition of the reactor, which may be years or decades later.

Dominion also touched on the discussion of records for plant components. Records requirements are limited to those needed for safety. Once the plant shuts down and the range of potential safety concerns decreases, systems are downgraded to non-safety and the associated records are no longer required to be maintained. For perspective, Kewaunee still has all its records four years since shutdown, but will likely not continue this much longer. Dominion closed its presentation with a broader perspective on harvesting, emphasizing the need to clearly define a problem statement and understand what technical and regulatory purpose this harvesting will serve. Early planning focused on achieving the clear objective of the work incliuding scope, schedule, budget and contact with plant is essential to a successful harvesting effort.

12

Discussion Summary The discussion touched on the top lessons learned from past harvesting efforts, which included a clear objective and purpose for harvesting, early engagement with the plant, and site coordination during harvesting.

Another suggestion was to get utility management buy-in for the harvesting project by identifying a benefit to the utility. EPRI mentioned that cable harvesting at Crystal River went much more successfully once the utility recognized the potential benefits for subsequent license renewal. Similarly, when harvesting from an operating plant, you need to recognize and work through the challenges the plant may encounter when restarting operations.

During discussion, the question was raised regarding how it is determined whether harvested materials are waste. The discussion concluded that in the U.S. 10 CFR 37 is the important consideration. 10 CFR 37 defines when additional security requirements are imposed, based on the quantity and activity of materials to be transported. The definition of material as waste versus research materials is not as critical in the U.S. EnergySolutions indicated that their shipments of waste or research material could be handled in the same way in the accordance with Department of Transportation regulations, provided that the limits in 10 CFR 37 were not reached.

Session 5 Future Harvesting Program Planning Session 5 focused on the information needed for informed harvesting decision-making and harvesting program planning. This session featured a presentation by Pradeep Ramuhalli from PNNL, followed by a discussion period covering harvesting program planning and reflection on the 2-day workshop.

Presentation Summary PNNL presented its perspective on the information needed for informed harvesting decision-making.

First, the purpose of the harvesting effort needs to be defined by identify the technical knowledge gaps to be addressed. Next, a research plan should be developed demonstrating how the harvested material will be used to address the identified gaps. Finally, the appropriate source of material to address the technical gap must be identified, along with resources to support the effort and plans and timelines to perform the harvesting. The specifics of these plans depend greatly on the source of materials and must be flexible based on changing conditions on the ground.

In assessing the best source of materials, researchers should consider the material, its environment, and its condition. Material information includes fabrication information such as manufacturer, composition, and dimensions as well as information related to installation or construction, such as welding processes and parameters. Environmental information includes temperature, humidity, fluence, flux, stress (service, residual, installation), and coolant chemistry. Component condition information includes inspection history, such as identified flaws or degradation.

Discussion Summary The discussion in Session 5 focused on the best practical approach to plan future harvesting programs.

There was clear agreement thait this approach must begin with identifying the data needs best addressed by harvesting, whether from operating or decommissioning plants. Once a specific need is 13

identified, the next step is to find a source to acquire the materials of interest as well as other organizations interested in participating in the harvesting effort.

Key Takeaways from Workshop Session 1 The clear takeaway from the discussion in session 1 was that harvesting requires significant resources to be done successfully; therefore it is paramount to identify how the planned harvesting will clearly address a significant need to ensure the harvesting project provides strong value. In the context of need for data, EPRI suggested the goal of harvesting to support research for operation out to 80 years is not a full comprehensive understanding of all aspects of the degradation, but rather a snapshot to confirm other lab results and models. This is an important point for all organizations and researchers to keep in mind before investing significant resources in harvesting.

Session 2 The criteria proposed by PNNL are a good starting point for prioritizing issues to address by harvesting.

Three additional important criteria would be:

Fleet-wide vs. plant-specific applicability of data, Ease of harvesting (in terms of cost and project risk), and Timeliness of the expected research results relative to the objective.

Once a potential harvesting project has reached the point of looking at different sources of materials, the availability of material pedigree information, such as composition, processing, environmental conditions (temperature, humidity, fluence, etc.) is very important to the overall value of harvesting from that particular plant.

Based on the presentations and discussion in Session 2, there appeared to be two areas with broad interest in pursuing further harvesting: high fluence reactor internals and irradiated concrete. The common drivers for the interest in these issues is a lack of representative data at the fluences of interest and significant challenges with acquiring representative data through other means. High fluence reactor internals has been addressed somewhat by the Zorita Internals Research Project (ZIRP), but stainless steel materials exposed to higher fluence levels at higher temperatures, where void swelling may become significant, could help validate DOE and EPRI models and provide further technical baisis for PWR internals aging management. Irradiated concrete harvesting is currently being pursued from the Zorita reactor in Spain, with international collaboration and potential testing at the Halden Reactor Project.

Other areas with some, but less widespread, interest expressed from workshop participants for new harvesting efforts included RPV materials and electrical cables and components. SCK-CEN and NRC expressed interest in RPV harvesting, and NRC expressed interest in electrical component harvesting.

Session 3 To capture the key takeaways from Session 3 focused on sources of materials, two tables of potential sources of materials are presented below. The first table covers recent or ongoing harvesting !Programs, while the second details potential future harvesting opportunities.

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Ongoing Harvesting Programs Country Plant Design Size Years in Components Organization(s)

(MWe) operation Canada NPD CANDU 20 25 Concrete AECL Gentilly-2 CANDU-6 675 29 Cables Japan Hamaoka 1 IBWR-4 540 33 RPV, concrete CRIEPI/Chubu Spain Zorita W 1-loop 160 37 Internals, concrete EPRI, NRC Sweden Barseback ABB-II 615 28 RPV Vattenfall Zion 1/2 W-4 1040 24/25 RPV, cables, DOE, EPRI, NRC loop neutron absorbers U.S.

Crystal River 3 B&W 860 36 Cables EPRI (b )( 4)

Potential Future Sources for Harvesting Country Plant Design Size Years in Potential Notes

{MWe) operation Components Canada NRU Test reactor 135 61 TBD AECL; SD:

MWt 2018 Germany Numerous plants either in decommissioning or shutting down soon. See Appendix Ill.

Japan Mihama W 2-loop 320 40 Concrete

Kansai, Westinghouse RPV, internals, Korea Kori 1 W 2-loop 576 40 SGs, pressurizer, KHNP, EPRI welds, CASS, Ringhals 1 BWR 883 44 RPV, internals Vattenfall; Sweden Ringhals 2 W 3-loop 900 44 SGs, pressurizer, SD: 2020 /

concrete 2019 Kewaunee W 2-loop 566 39 TBD SD: 2013 SONGS 2/3 CE 2-loop 1070 31/30 TBD SD: 2013 Crystal River 3 B&W 860 36 TBD SD: 2013 Vermont BWR-4/Mk-1 605 42 TBD SD:2015 Yankee Fort Calhoun CE 2-loop 482 43 TBD SD:2016 Palisades CE 2-loop 805 47 TBD SD:2018 Pilgrim BWR-3/Mk-1 677 47 TBD SD: 2019 U.S.

Oyster Creek BWR-2/Mk-1 619 50 TBD SD: 2019 Indian Point W 4-loop 1020 /

48/46 TBD SD: 2021 2/3 1040 Diablo Canyon W 4-loop 1138/

40 TBD SD: 2024-5 1/2 1118 Non-Advanced 250 commercial; Test Reactor Test reactor MWt 50 Core internals internals replaced every 10 years 15

In addition to the potential sources of materials presented and discussed in Session 3, another takeaway was the suggestion of developing a database for previously harvested materials or those available for future harvesting. The NSUF sample library may be a good starting point for such a database, with appropriate modifications for the purposes of harvesting efforts.

Session 4 There were several important takeaways from Session 4 that were touched on in multiple presentations and the discussion. One key takeaway is that researchers should identify a clear purpose and scope for harvesting. Having a clear purpose for harvesting helps to guide later decisions that must be made to adjust course when the inevitalble changes in schedule or unexpected realities at the plant arise. A related note is that harvesting iis not the top priority for decommissioning. Therefore, researchers must have clear objectives and scope for harvesting that can be communicated to the site. This understanding should shape assumptions and interactions with the plant owner or decommissioning company as well as planning for costs and schedule.

Another takeaway was the value of strong site coordination, including site visits. Multiple presenters touched on the value of being on-site to talk to staff and see the components to be harvested. Mock ups and 3-D simulations can be valuable to ensure success of the approach or technique used to acquire the specimen. A related point is working with reactor operators at the plant. Several harvesting efforts worked with former reactor operators and benefited greatly from their experience to find records or determine the best method to harvest the desired component. This is a valuable insight that could be effective in future harvesting efforts.

A third key takeaway is early engagement with the plant to express interest in harvesting. This serves to make the plant aware of your interest in harvesting and get their support to work with the harvesting process. The other important benefit of early engagement is to gain as much information as possible about the available materials and components, including the associated records and material pedigree information.

Session 5 The key takeaway in session 5 was to gather as much information as possible in advance of committing to a specific harvesting project. Ideally, there would be a strong understanding that the material and its aging conditions clearly align with an identified technical data need before committing significant resources to a harvesting effort.

Action Items and Next Steps The following is a summary of the action items discussed at the end of the workshop:

1. Sharing workshop slides NRC emailed attendees to ask their comfort with sharing their workshop slides with other organizations and received no objection from any presenters.

The presentations can be accessed here:

https ://drive.google.com/ open ?id =OBS DWM LchSYSXcn pZZ0JOS0SSQU U.

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2.

EPRI indicated that MRP-320 (Product ID: 1022866) on knowledge gaps for irradiated austenitic stainless steel for potential harvesting from MRP-227 inspections is publicly available for a fee.

3.

Cable surveillance programs in Germany GRS to inquire with cable colleagues and share any insights.

4. Sources of materials database Potential sources of materials presented in this workshop are summarized in Session 3 summary above and Appendix Ill below.

NRC will be reaching out to PNNL, INL NSUF, CNSC, AECL, and any other organizations interested in database development.

5.

Prioritized data needs Suggestion to continue discussions on prioritiz.ed data needs within technical areas (RPV, internals, electrical, concrete) through existing coordination groups if possible Focus on identifying specific material/ aging conditions of interest and purpose

/ intended outcome of harvesting Idea to survey Env Deg participants John Jackson (INL) is on planning committee

6.

EPRI report on spent fuel liner boric acid transport through concrete NRC will contact EPRI for report if needed.

7.

Harvested Materials Research Results Section of workshop summary report (below) devoted to references from harvested materials research.

References to Previous Harvested Materials Research This section of the workshop summary addresses a question that was raised during the discussion at the workshop regarding what the outcome or benefit of past harvesting efforts have been. Below is a list of references to research results generated from testing of harvested materials:

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Appendix I Workshop Participants Name Organization Email Taku Arai CRIEPI arait@crieoi.denken.or.io Sadao Higuchi CRIEPI higuchi@criegi.denken.or.jg Japan Kazunobu Sakamoto JNRA kazunobu sakamoto@nsr.go.jg Yasuhiro Chimi JAEA chimi.yasuhiro@jaea.go.jg Uwe Jendrich GRS Uwe.Jendrich (ci) ins.de Europe Rachid Chaouadi SCK-CEN rachid.chaouadi@sckcen.be Guy Roussel BelV guy.roussel@Belv.be Daniel Tello CNSC daniel.tello@canada.ca Canada Desire Ndomba CNSC desire.ndomba@canada.ca Karen Huynh AECL kh uynh@aecl.ca Gerrv van Noordennen Energy Solutions 12ovannoordennen@energvsolutions.com us Bill Zipp Dominion william.f.zigg@dom.com industry Mark Richter NEI mar@nei.org Arzu Alpan Westinghouse alganfa@westinghouse.com Sherrv Bernhoft EPRI sbern hoftca>eori.com Robin Dyle EPRI rdy:le@egri.com EPRI Jean Smith EPRI jmsmith@egri.com Al Ahluwalia EPRI kahluwal@egri.com Tom Rosseel ORNL rosseeltmca>ornl.gov Rich Reister DOE Rich a rd. Reister@nuclea r.energy.gov Keith Leonard ORNL leonardk@ornl.gov DOE Mikhail A. Sokolov ORNL sokolovm@ornl.gov John Wagner INL john.wagner@inl.gov John Jackson INL john.jackson@inl.gov Pradeep Ramuhalli PNNL Pradeeg.Ramuhalli@gnnl.gov Pat Purtscher NRC Patrick. Pu rtscherca> nrc.12ov Rob Tregoning NRC Ro bert.Tregoning@nre.gov Matt Hiser NRC Matthew.Hiser@nrc.gov Mita Sircar NRC Madhumita.Sircar@nrc.gov Tom Koshy NRC Thomas.Koshy@nrc.gov NRC Jeff Poehler NRC Jeffrey. Poehler@nrc.gov Allen Hiser NRC Allen.Hiser@nrc.gov Angela Buford NRC Anigela.Buford@nrc.gov M ark Kirk NRC Mark.Kirk@nrc.gov Amy Hull NRC Amy.Hull@nrc.gov Pete Ricardella NRC/ACRS Pri cca rdel la@Structint.com 18

Session Time Intro 8:00 1

8:15-8:45 8:45 - 9:45 9:45-10:00 10:00-10:20 10:20-10:30 10:30 -

10:55 2

10:55 -

11:20 11:20 -

11:45 11:45 -

12:30 12:30- 2:00 2:00 - 2:10 2:10- 2:35 2:35-2:50 2:50 - 3:00 3:00- 3:15 3

3:15-3:30 3:30- 3:45 3:45-4:00 4:00-4:15 4:15-5:00 Appendix II Workshop Agenda Tuesday, March 7 Organization Speaker Presentation Title NRC Michael Weber Welcome and Introduction to Workshop Robert Tregoning DOE Rich Reister DOE Perspectives on Material Harvesting EPRI Sherry Bernhoft EPRI Perspective on Harvesting Projects NRC Robert Tregoning NRC Perspective on Motivation for Harvesting GRS Uwe Jendrich Role of GRS in Decommissioning and LTO CRIEPI Taku Arai CRIEPI Motivations for Harvested Material DISCUSSION BREAK PNNL (for NRC)

Pradeep Ramuhalli Data Needs Best Addressed By Harvesting NRC Matthew Hiser High-Priority Data Needs for Harvesting DOE Keith Leonard LWRS Program Perspective on the Technical Needs for Harvesting Review of past RPV sampling test programs SCK-CEN Rachid Chaouadi and perspective for long term operation Westinghouse Arzu Alpan Importance of Harvesting to Evaluate Radiation Effects on Concrete Prooerties DISCUSSION LUNCH NRC Matthew Hiser Sources of Materials: Past NRC Harvesting and U.S. Decommissioning Plants EPRI Al Ahluwalia Harvesting Plans for Materials Aging Degradation Research in Korea and Sweden DOE/ORNL Tom Rosseel Materials Harvested by the LWRS Program DOE/I NL John Jackson NSUF Material Sample Library Energy Solutions Gerry van Zion Material Harvesting Program Noordennen Potential Harvesting of Concrete from Mihama Westinghouse Arzu Alpan Unit 1 BREAK GRS Uwe Jendrich Plants in Decommissioning in Germany Evaluating Structures, Systems & Components CNSC Daniel Tello from Decommissioned/Decommissioning Nuclear Facilities in Canada DISCUSSION 19

Wednesday, March 8 Session Time Ori?anization Speaker Presentation Title 8:00-8:30 EPRI Jean Smith Lessons Learned: Harvesting and Shipping of Zorita Materials 8:30-9:00 DOE Tom Rosseel LWRS Program: Harvesting Lessons Learned 9:00 - 9:30 NRC Matthew Hiser NRC Perspective on Harvesting Experience and Lessons Learned 9:30 -10:00 CRIEPI Taku Arai CRIEPI Research Activities with Harvested 4

Materials 10:00 - 10:15 BREAK 10:15 - 10:45 Energy Gerry van Zion Harvesting Experience and Lessons Solutions Noordennen Learned 10:45 - 11:15 Dominion Bill Zipp Kewaunee Insights on Material Harvesting 11:15 - 12:00 DISCUSSION 12:00-1:30 LUNCH 1:30 - 1:45 PNNL (for Pradeep Ramuhalli Technical Information Needed for Informed NRC)

Harvesting Decisions 1:45-2:30 DISCUSSION 5

2:30 - 3:00 Action Items and Next Steps EPRI Sherry Bernhoft DOE Rich Reister Closing Thoughts 3:00 - 4:00 NRC Robert Tregoning ALL 20

Appendix Ill Harvesting Opportunities in Germany

• Past and current decommissioning projects of Prototype or Commercial Reactors Name Reactor type --

Strategy Rheinsberg KKR WWER 70 1995 UC Compact Natrium Cooled KKN SNR 21 1993 UC Reactor Multipurpose Research R.

MZFR PWR/O20 57 1987 UC Obrigheim KWO PWR 357 2008 UC Neckarwestheim 1 GKN-1 PWR 840 2017 UC lsar-1 KKl-1 BWR 912 2017 UC Gundremmingen-A KRB-A BWR 250 1983 RCA KRB-11 Greifswald 1-5 KGR 1-5 WWER 440 1995 UC Lingen KWL BWR 268 1985 UC after SE UC: unconditional clearance RCA: radiation controlled area, new license NRC Harvesting Workshop, Rockville, March 2017, Decommissioning In Germany SE: safe enclosure 4

• Past and current decommissioning projects of ? ototype or Commercial Reactors Name Stade Research Reactor Julich Thorium High-Temperature-Reaktor Wurgassen Mulheim-Karlich Hot-Steam Reactor Grosswelzheim N iederaichbach Test-Reactor Kahl KKS AVR THTR-300 KWW KMK HOR KKN VAK Reactor type PWR HTR HTR BWR PWR HOR ORR/O2O BWR 21 Strategy 672 2005 UC 15 1994 UC 308 1993 SE since 1997 670 1997 UC 1302 2004 UC 25 1983 UC since 1998 106 1975 UC since 1994 16 1988 UC since 2010

Shut down Cor1r1erc*a1 ~Qactors

• that have no decommissioning license granted yet Name Abbrev.

Reactor type PowerMWe Philippsburg-1 KKP-1 BWR 926 Grafenrheinfeld KKG PWR 1345 Biblis-A KWB-A PWR 1225 Biblis-B KWB-B PWR 1300 Unterweser KKU BWR 1410 BrunsbUttel KKB BWR 806 Krummel KKK BWR 1402

• Commercial Reacto In operation Name Abbrev.

Reactor type Power MWe Gundremmingen-B KRB-11-B BWR 1344 Philippsburg-2 KKP-2 PWR 1468 Gundremmingen-C KRB-11-C BWR 1344 Grohnde KWG PWR 1430 Brokdorf KBR PWR 1480 Emsland KKE PWR 1406 lsar-2 KKl-2 PWR 1485 Neckarwestheim-2 GKN-2 PWR 1400 22 Date of application 2013 / 2014 2014 2012 2012 2012 / 2013 2012 / 2014 2015 Anticipated date of final shutdown 31.12.2017 31.12.2019 31.12.2021 31.12.2021 31.12.2021 31.12.2022 31.12.2022 31.12.2022