ML22297A041
| ML22297A041 | |
| Person / Time | |
|---|---|
| Issue date: | 10/06/2022 |
| From: | Advisory Committee on Reactor Safeguards |
| To: | |
| References | |
| NRC-2113 | |
| Download: ML22297A041 (1) | |
Text
Official Transcript of Proceedings NUCLEAR REGULATORY COMMISSION
Title:
Advisory Committee on Reactor Safeguards Docket Number:
(n/a)
Location:
teleconference Date:
Thursday, October 6, 2002 Work Order No.:
NRC-2113 Pages 1-75 NEAL R. GROSS AND CO., INC.
Court Reporters and Transcribers 1716 14th Street, N.W.
Washington, D.C. 20009 (202) 234-4433
NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com 1
1 2
3 DISCLAIMER 4
5 6
UNITED STATES NUCLEAR REGULATORY COMMISSIONS 7
ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 8
9 10 The contents of this transcript of the 11 proceeding of the United States Nuclear Regulatory 12 Commission Advisory Committee on Reactor Safeguards, 13 as reported herein, is a record of the discussions 14 recorded at the meeting.
15 16 This transcript has not been reviewed, 17 corrected, and edited, and it may contain 18 inaccuracies.
19 20 21 22 23
1 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com UNITED STATES OF AMERICA 1
NUCLEAR REGULATORY COMMISSION 2
+ + + + +
3 699TH MEETING 4
ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 5
(ACRS) 6
+ + + + +
7 THURSDAY 8
OCTOBER 6, 2022 9
+ + + + +
10 The Advisory Committee met via hybrid 11 In-Person and Video-Teleconference, at 8:30 a.m. EDT, 12 Joy L. Rempe, Chairman, presiding.
13 COMMITTEE MEMBERS:
14 JOY L. REMPE, Chairman 15 WALTER L. KIRCHNER, Vice Chairman 16 DAVID A. PETTI, Member-at-Large 17 VICKI M. BIER, Member 18 VESNA B. DIMITRIJEVIC, Member 19 GREGORY H. HALNON, Member 20 JOSE MARCH-LEUBA, Member 21 MATTHEW W. SUNSERI, Member 22 ACRS CONSULTANT:
23 DENNIS BLEY 24 STEPHEN SCHULTZ 25
2 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com DESIGNATED FEDERAL OFFICIAL:
4 ALSO PRESENT:
5 ELIJAH DICKSON, NRR 6
JEREMIAH DOYLE, NuScale 7
TYLER ELLIS, Public Participant 8
SID FOWLER, Public Participant 9
RAYMOND FURSTENAU, RES 10 MATTHEW HISER, RES 11 STEVE LYNCH, NRR 12 SCOTT MOORE, ACRS 13 JEFFREY POEHLER, RES 14 ANDREW PROFFITT, NRR 15 WILLIAM RECKLEY, NRR 16 MO SADOLLAH, RES 17 DIEGO SAENZ, Department of Homeland Security 18 MOHAMED SHAMS, NRR 19 MADHUMITA SIRCAR, RES 20 JOSEPH STAUDENMEIER, RES 21 GABE TAYLOR, RES 22 ROBERT TREGONING, RES 23 DUNCAN WHITE, NMSS 24 25
3 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com C-O-N-T-E-N-T-S 1
Item Page 2
Research Briefing on Materials Harvesting 3
(Open) (MS/HN) 4 8.1) Remarks from the Subcommittee Chairman 5 5
8.2) Presentation and discussion with the 6
NRC staff 6 7
8 9
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
4 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com P-R-O-C-E-E-D-I-N-G-S 1
(8:30 a.m.)
2 CHAIR REMPE: Good morning, this is the 3
meeting. The meeting will now come to order. This 4
is the second day of the 699th meeting of Advisory 5
Committee on Reactor Safeguards. I'm Joy Rempe, 6
chairman of the ACRS.
7 Other members in attendance are Vicki Bier, 8
Vesna Dimitrijevic, Greg Halnon, Walt Kirchner, Jose 9
March-Leuba, Dave Petti, and Matt Sunseri.
10 During today's meeting, the committee will 11 first conduct its Planning and Procedures meeting at 12 1:30. The committee will be provided an information 13 briefing by the Office of Research on harvesting 14 materials, and after that time we will continue with 15 our letter writing.
16 If we finish the P&P subcommittee, our full 17 committee meeting early, we will also have some time 18 to continue on our letter writing from yesterday.
19 The designated federal official for 20 today's meeting is Larry Burkhart, and at this point 21 we're going to go off the record, but I would like to 22 ask the court reporter to return at 1:30 for our second 23 topic. And so at this point, I'd like to ask Larry 24 Burkhart, the designated federal official, to lead us 25
5 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com through our Procedures and Planning meeting discussion.
1 MR. BURKHART: Okay. Thank you, 2
Chairman. I will start with --
3 (Whereupon, the above-entitled matter went 4
off the record at 8:31 a.m. and resumed at 1:30 p.m.)
5 CHAIR REMPE: Okay, I have that it's 1:30 6
on the East Coast here and I'd like to ask Matt Sunseri 7
to lead us through our next topic.
8 MEMBER SUNSERI: Thank you, Chair Rempe.
9 So my name's Matt Sunseri, I'm the ACRS lead member 10 for the engineering section of our periodic review of 11 the NRC Safety Research Program. We've asked staff 12 to be here today with us to have a informational briefing 13 updating us on activity since our last periodic review.
14 In that report, one of the items that we 15 identified was that we asked staff to consider if there 16 was any opportunity to add a quote, predictive modeling 17 capability to aging management strategies, along with 18 the current approach of establishing limits on life.
19 So they had a chance to look through the 20 material that will be presented today, and I think the 21 staff has information in there that touches on that 22 topic, so I'm happy to see, you know, that.
23 Without any further ado, I'd like to now 24 turn over to Ray Furstenau, the director of the Nuclear 25
6 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com Regulatory Research Office. Ray?
1 MR. FURSTENAU: Yeah thanks, Mr. Sunseri, 2
and thanks, Chairman. Really on behalf of the Office 3
of Research, I really appreciate the committee having 4
these information briefings on specific topic areas.
5 As research director, I really find them 6
helpful to guide us in kind of bouncing off ideas on 7
our research program, and material harvesting is a big 8
one of course, and it takes time, it's expensive, and 9
you want to focus your resources where it makes the 10 most sense. So we appreciate this opportunity.
11 As you mentioned on the slides, there was 12 some background history of harvesting components and 13 our harvesting strategy, and how we prioritize the work 14 we're doing and are planning to do, and how we're 15 leveraging with other organizations like DOE and EPRI 16 to zero in on what makes the most sense.
17 You know, the timing is kind of good right 18 now. I think most of us hate to see perfectly good 19 plants maybe shutting down early or and 20 decommissioning, but it does provide us an opportunity 21 to focus in on these passive components that we would 22 like to get data on.
23 So it's a good opportunity to do that and 24 we're trying to take advantage of that, be selective, 25
7 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com and with our partners and foreign as well as here in 1
the US to do that. And I think towards the presentation 2
we will go into a little bit more detail on the recent 3
and the current harvesting activities.
4 You know, although the NRC's had sufficient 5
confidence with our aging management programs we have 6
right now, and that has supported a license renewal, 7
testing of harvested materials on these passive 8
components really allows us to confirm that the existing 9
aging strategies in place were appropriate, and or we 10 adjust the strategies as needed because I think we would 11 all agree that effective aging management of 12 safety-related passive components is just essential 13 for safe operations.
14 So our activities are focused on issues 15 associated again with the safety significant component, 16 some passive components, of harvested material 17 research.
18 Again, you'll hear that it's prioritized 19 to attract conservatisms and uncertainties in the basis 20 of our existing guidance, and as with all regulatory's 21 research, it's kind of about uncertainties and 22 sensitivities, and when you look at uncertainties and 23 get data to reduce those uncertainties, you may find 24 out there's very conservatism and you have margin, or 25
8 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com you may find out it isn't as conservative an issue as 1
you thought.
2 So all of this is all part of the strategy 3
that we have of the harvesting and examining harvesting 4
material. And again, it helps us look at aging 5
management strategies.
Do they need to be 6
strengthened, do they need to be relaxed? And that's 7
kind of tied into the getting data to understand 8
uncertainties.
9 It also can support as we look into aging 10 beyond 80 years, you know, 60 to 80, but beyond 80 you 11 may have plans that might want to do that later on.
12 So I think that this all ties into that quite well, 13 so I'm kind of excited the group of folks that you have.
14 I'm going to get off of here, let the smart people 15 talk.
16 So I'm going to turn it over to Jeff Poehler 17 and Matt Hiser, and give up my chair to Rob Tregoning, 18 and I think they can answer any questions that come.
19 So again, thanks for the opportunity.
20 MEMBER SUNSERI: Before you sit down I'll 21 ask the members, any questions for Ray before he steps 22 down?
23 (No audible response.)
24 MEMBER SUNSERI: All right. Well, thanks 25
9 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com for those opening remarks. Jeff?
1 MR. POEHLER: Can everyone hear me?
2 (Off-microphone comment.)
3 MEMBER SUNSERI: That's kind of a 4
directional, so if you can get that microphone pointed 5
right at your mouth? It's flexible so you can bend 6
it. Okay, all right.
7 MR. POEHLER: How's that?
8 (Simultaneous speaking.)
9 MR. POEHLER: How's that?
10 (Off-microphone comment.)
11 MR. POEHLER: Okay. Good afternoon. So 12 as Ray said, my name is Jeff Poehler, I'm a senior 13 materials engineer in the reactor engineering branch 14 in the Office of Research. And I'm supported today 15 in this presentation by Matthew Hiser and Rob Tregoning.
16 Matt is going to be presenting the second 17 half of the slides, and I kind of have to introduce 18 myself because I'm kind of new to the harvesting area.
19 I'm taking over Matt's role. Matt has really been 20 the lead and the subject matter expert in research on 21 harvesting for several years at least.
22 He's recently accepted a promotion to NRR 23 as a senior project manager in NRR Danyou [phonetic],
24 so I'm stepping in, but I'm certainly going to rely 25
10 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com on Matt if there's any tough questions, and also Rob 1
Tregoning who's been heavily involved in harvesting 2
for quite some time.
3 He was our senior-level staff materials 4
engineering in the Division of Engineering and Office 5
of Research. With that to it, so this is what we're 6
going to be talking about today.
7 First we'll talk about background on 8
harvesting. We'll talk about the motivation and 9
strategy for harvesting, which includes the NRC's 10 harvesting priorities, we'll talk about the use of 11 previously harvested materials, we'll talk about 12 harvesting opportunities that the NRC staff is tracking 13 and looking at.
14 Then we'll talk about recent and current 15 activities in materials harvesting, and that includes 16 metals, concrete, components important to fire 17 research and electrical components. We'll touch on 18 outreach and partnership with other organizations, and 19 we'll end with conclusions and key messages.
20 So, oops, I skipped a slide.
21 So, harvesting background.
So 22 historically, NRC industry and others have performed 23 research on materials harvested from a broad range of 24 components. And our current harvesting objectives 25
11 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com focus on materials aging during long-term operation.
1 There are two basic objectives. One is 2
to confirm results from laboratory experiments and 3
simulations or models to prove understanding of aging 4
by testing materials aged in operating plants.
5 Secondly, to reduce uncertainty in the 6
current state of knowledge of aging and the 7
effectiveness, to enable informed NRC review of aging 8
management programs.
9 So what's the current situation with regard 10 to harvesting? Well, in the past harvesting efforts 11 have generally been reactive. You know, they were 12 limited to opportunities that arose, and that was 13 because there were few plants shutting down, that led 14 to more of a demand for, you know, harvesting materials, 15 and there was supply.
16 However, in recent years a significant 17 number of plants have shut down and entered the 18 decommissioning process. And so those plants have 19 generally operated for a long period, some, you know, 20 many more than 40 calendar years, which provides more 21 highly aged components for harvesting.
22 And currently we have more of a supply of 23 harvesting opportunities than in the past (audio 24 interference) advances. So therefore, the current 25
12 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com situation calls for a more proactive, strategic 1
approach.
2 So, the NRC staff really began around 2015 3
began with an effort to develop the materials harvesting 4
strategy. Previously, we were very relatively 5
reactive to harvesting opportunities. In developing 6
this strategy there are a number of challenges.
7 First, harvesting is expensive, complex, 8
and time-consuming, particularly when involving 9
irradiated materials.
10
- Second, documentation of component 11 fabrication and aging conditions is often difficult 12 and time-consuming. You know, generally, material 13 information is available. Sometimes it takes some 14 digging to get it.
15 Aging conditions, such as neutron fluence, 16 for example, you know, I'll give an example of reactor 17 internals components. Often, there are not detailed 18 fluence maps of internals readily available. They can 19 be generated but they're not always available, so that 20 can be a challenge. Also operating temperature.
21 MEMBER MARCH-LEUBA: Willing to help you 22 all. What's the proportion of the job and the 23 documenting the condition of the way it has operated?
24 Does it drive you towards sampling other things that 25
13 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com you can may -- if you have two -- option A, option B, 1
you have a good map of the (audio interference) A doesn't 2
cover it, but A may have some more value. Do you --
3 how can you weigh that?
4 MR. POEHLER: Well, I think we would 5
probably go with the harvesting the material that's 6
more value to us, or higher priority. I'm going to 7
talk about the priorities.
8 (Simultaneous speaking.)
9 MR. POEHLER: You know, usually, you know, 10 things like a fluence map, for example, can be 11 generated. This costs us money, so. You know, I think 12 if we had an idea that this was a high priority material 13 to harvest, we would try to make that happen.
14 MEMBER MARCH-LEUBA: And would you 15 consider like something more than you can analyze, and 16 save it in a hold somewhere?
17 MR. POEHLER: Yeah, I mean, that is an 18 option too, to harvest materials and not test them until 19 later, you know, to archive materials.
20 MEMBER MARCH-LEUBA: Do you do that 21 because now we have an opportunity to collect (audio 22 interference) and just from my point of view --
23 MR. POEHLER: And sometimes we do that just 24 because we don't necessarily have the budget to test 25
14 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com some of aging stuff. But yeah, there are definitely 1
archived (audio interference) existing, and that is 2
definitely an option to do.
3 MEMBER HALNON: So, going further, do you 4
take samples out of decommissioned sites and put them 5
back into like a coupon sample into existing to get 6
a higher fluence?
7 MR. POEHLER: Yeah, I mean that can be 8
done, that's something that can be done, and has been 9
done, you know, to take something that's irradiated 10 and let's say put it in a test reactor and irradiate 11 it more, to get higher results.
12 MR. HISER: Can I just add --
13 MR. POEHLER: Go ahead.
14 MR. HISER: And I apologize. I'm just 15 wearing a mask, I kind of lost my voice yesterday, I 16 don't think I'm contagious, I don't feel sick at all, 17 but just wanted to set everyone at ease.
18 I just wanted to get back to the initial 19 question and just shed a little more light. I think 20 related to the documentation issue, it really comes 21 into identifying and choosing between opportunities 22 just like you were suggesting.
23 And so that becomes a challenge, is 24 knowing, having a good understanding of what is the 25
15 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com fabrication and the aging conditions, planned 1
components at different plants, if meaningfully 2
distinguished?
3 Because, you know, it may cost half a 4
million dollars, $1,000,000 to do a really detailed 5
fluence analysis and know what's the exact fluence 6
levels for your plant.
7 We can't go do that at ten different plants 8
and then say which one do we want? You know, that's 9
just impractical.
10 So we kind of have to use the information 11 we do have through designs, through industry-wide, you 12 know, how long did a plant operate, what do we understand 13 about that design?
14 Make informed decisions, then once we 15 choose to jump on an opportunity, see if we're going 16 to pursue it, ideally with partners, maybe DOE, EPRI, 17 international organizations, then we may need to 18 invest, you know, in the course of implementing that 19 project, we may need to spend collectively the group, 20 whatever it takes to, you know, sufficiently analyze 21 them so when we get results we know we're looking at 22 20 DPA material, not 10 DPA material, for instance.
23 Hopefully that kind of helps give a little 24 bit more.
25
16 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com MR. HISER: Yeah, that seemed to do it.
1 MR. POEHLER: And I think we'll get on to 2
it. Okay?
3 MEMBER SUNSERI: Yeah, no, that's a good 4
summary of the next ten slides, but why don't we just 5
go ahead and move on?
6 MR. TREGONING: Well, I think it's 7
important -- Rob Tregoning from the staff -- I did want 8
to clarify Chairman Allen's question. So Jeff answered 9
it correctly, there are instances where we pull 10 materials out and machine them out, and then put them 11 in test reactors.
12 The other thing that we do, the one area 13 of harvesting which is actually required in the 14 regulations, is surveillance testing, and we've done 15 that since the plants were built, right, and that's 16 how we monitor reactor pressure vessel and (audio 17 interference).
18 So you'll see today that we don't talk 19 anything about the surveillance program, so when we 20 talk about harvesting, we're not talking about the 21 surveillance program.
22 Surveillance program they exactly do that 23 as well, they have a very coordinated plan that they've 24 developed that we review and approve, and they make 25
17 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com sure that they have coverage in terms of the conditions 1
that they need to sample and understand out in the fleet.
2 It goes from a fluence perspective, but then also a 3
chemistry perspective.
4 So it's very, you know, precise and 5
regimented in the surveillance program. We won't talk 6
about that here, but we certainly do similar strategies 7
with materials that we have if we want to examine 8
extended conditions as well.
9 MEMBER HALNON: Yeah thanks, and this is 10 Greg. The point of my question was that connection 11 because I know that we're running out of surveillance 12 specimens for the higher fluences so if you take, you 13 know, a shut down plant that's exceeded it, and the 14 way of extending that, we'll put more materials in.
15 So I was just wondering about that 16 connection between you and the surveillance program, 17 but I realize that, you know, it's all the same 18 materials, people are looking at the same stuff. So, 19 I understand.
20 MR. POEHLER: And then the third challenge 21 is, you know, the decommissioning versus harvesting.
22 So, you know, a decommissioning company 23 trying to decommission a plant has a different objective 24 than a person that wants to harvest materials, and 25
18 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com sometimes those two things sort of conflict because 1
the decommissioning schedules are often, you know, very 2
tight and you have to fit harvesting in, and it 3
definitely would impact decommissioning activities 4
schedule, and also, you know, the storing and 5
transporting of harvest materials can add to an already 6
complicated process.
7 So you know, because of all these 8
challenges, the NRC staff is just, you know, basically 9
trying to focus on high value harvesting opportunities.
10 And also to seek cooperation and collaboration when 11 possible to maximize limited NRC resources.
12 Now I'm going to talk about the elements 13 of the NRC's proactive harvesting strategy. So the 14 first element is to identify and prioritize harvesting 15 interests. That process is going to focus on the unique 16 value of harvesting relative to other sources of 17 information, such as accelerated aging in a laboratory 18 or test reactor, and use of operating experience.
19 The second element would be considered use 20 of previously harvested materials when possible.
21 That, you know, has greatly reduced cost, time, and 22 complexity compared to new harvesting, however it's 23 limited in the range of materials in aging conditions 24 that are available.
25
19 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com And the third element is to gather 1
information on harvesting opportunities. That 2
requires sufficient information to be equally 3
comparative priorities, but it's kind of like, you know, 4
what we talked about, making the best decisions with 5
the information we have, such as operating conditions 6
and things like that.
7 And then it's also challenging to acquire 8
that information across the population of 9
decommissioning plants. You know, you generally need 10 to have the cooperation of, you know, the owner and 11 other industry groups to help get that information, 12 and it's a lot of legwork.
13 Next I'm going to talk about the technical 14 prioritization criteria that the NRC staff applies in 15 our strategy. The first one is the criticalness of 16 the technical issue addressed. So, they're high safety 17
-- I don't know why I (audio interference) --
18 MR. FURSTENAU: (audio interference) When 19 he talks too long, I think it --
20 (Simultaneous speaking.)
21 MR. POEHLER: Could be, yeah. Clearly, 22 I guess PowerPoint's trying to send me a message. But 23 24 (Simultaneous speaking.)
25
20 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com (Laughter.)
1 MR.
POEHLER:
So, higher safety 2
significance components and with less available data 3
would leave to a higher ranking for that type of 4
component.
5 Second criteria is the importance of 6
harvested material over laboratory aging, so in plant 7
aging conditions or materials that are more difficult 8
to replicate at the lab leads to a higher ranking.
9 You know, for example, let's do the combination of 10 thermal aging and irradiation for cast austenitic 11 stainless steels, it's hard to replicate in the lab.
12 And then the third criteria is 13 applicability to the U.S. operating fleet. So, the 14 more plants in the fleet that a particular issue is 15 applicable to, would lead to a higher ranking.
16 And fourth, regulatory considerations 17 related to inspections in aging management programs.
18 So greater availability and confidence in inspection 19 methods or aging management approaches leads to a lower 20 ranking, so if you have a component that has a robust 21 inspection program or condition monitoring program that 22 gathers a lot of data regularly, versus a component 23 where you really have difficulty inspecting it, like 24 certain parts of the reactor internals and things like 25
21 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com that are difficult to inspect.
1 MR. HISER: Jeff, may I go? Can I --
2 MR. POEHLER: So --
3 MR. HISER: Can I --
4 MR. POEHLER: Yeah, go ahead, Matt.
5 MR. HISER: Yeah, so I was going to say, 6
so an example for instance -- one example of a very 7
inspectable component is the --
8 (Audio interference.)
9 MR. HISER: Oh, sorry.
10 (Audio interference.)
11 MR. HISER: Okay. Thanks, Steve. Matt 12 Hiser. Just an example of one that's easily inspected, 13 baffle bolts, for instance.
14 The industry does, and has committed to 15 doing 100 percent inspections on baffle bolts as they 16 enter the extended operation period, so you know, while 17 baffle bolts may be -- they are a relatively low safety 18 significant component, but they also -- from the 19 standpoint of this criteria, we wouldn't really be as 20 focused on them for harvesting because we consider them 21 to be handled by a very robust aging management 22 inspection program.
23 Conversely, something that may have to do 24 with embrittlement or loss of toughness, very 25
22 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com difficult, you know, or not at all possible to inspect.
1 Those may be the types of issues that on safety 2
significant components, we would focus more on for 3
harvesting. And I apologize for my voice.
4 CHAIR REMPE: I have a --
5 (Simultaneous speaking.)
6 CHAIR REMPE: Well, okay. I apologize if 7
you've already said this, but this is something that 8
just the NRC staff uses for your prioritization, or 9
do you ever include other experts that are in the fields?
10 I'm glad to hear you consider what else is going on 11 in the field, but this is just an internal research 12 organization that is doing the ranking?
13 MR. HISER: Yeah, I mean, well, I mean, 14 within the NRC, we research a week, coordinate with 15 our stakeholders and the program offices, particularly 16 NRR, but also, you know, we also collaborate with other 17 parties and organizations, such as EPRI and DOE.
18 CHAIR REMPE: Oh, you show your rankings 19 and then if --
20 MR. HISER: Oh --
21 CHAIR REMPE: We said oh no, but you 22 forgot, you might change them, or how does that work?
23 MR. HISER: Yeah, correct me if I'm wrong, 24 Matt, but with EPRI we do kind of come up with joint 25
23 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com rankings.
1 MEMBER SUNSERI: Yeah. I'll circle back 2
on the first part of your question too, Dr. Rempe.
3 So, we about three years ago sort of went through these 4
criteria internally, staff and NRR and research and 5
the materials area, with knowledge in of specific 6
components and aging conditions, went through and they 7
spent, you know, several lengthy meetings looking 8
through tables identifying interests and then 9
prioritizing them through these criteria.
10 So we sort of established internal agency 11 priorities. We then have carried those priorities into 12 discussions. We've had a couple workshops, including 13 international parties. We've also have regular 14 coordination with DOE lab staff and EPRI, and we have 15 had some opportunities to share and exchange views on 16 priorities.
17 There are similarities, you know, not 100 18 percent, line up with maybe where NRC's high priorities 19 are and EPRI's or DOE's. But we have done that, but 20 this criteria, or NRC's criteria that we have used for 21 internal, you know, discussion in identifying our 22 priorities. And we have identified that we're planning 23 to update these.
24 We haven't really done an update in about 25
24 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com two or three years, we sort of implicitly do, but we're 1
not going to do a rigorous update. We'll probably do 2
that sometime in the next couple years.
3 CHAIR REMPE: That helps, thank you.
4 VICE CHAIR KIRCHNER: I was just going to 5
ask you a question at a higher level, going back to 6
Ray's introduction, I would presume by now (audio 7
interference) all the other work you've done and what 8
you're getting from your inspectors in the fields on 9
(audio interference), it seemed to be you would start 10 at a component or a higher level and then say okay, 11 of these components, these are critical to safety 12 considerations in the fleet, these we have a lot of 13 confidence on, others we don't, we now have the property 14
-- the material properties degrade or don't with age, 15 corrosion, radiation, whatever.
16 Is there some higher level, you know, 17 starting point that you're using to -- and then, I 18 understand your criteria and such. Have you -- based 19 on the experience you collectively have, do you have 20 a few targets of opportunity that are high on your list 21 or?
22 (No audible response.)
23 VICE CHAIR KIRCHNER: So you see where I'm 24 going with this?
25
25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com MR. HISER: Yeah, I understand.
1 VICE CHAIR KIRCHNER: And then what these 2
really -- do you have good models, or I'll make something 3
up for radiation influence on stainless steel --
4 (Audio interference.)
5 VICE CHAIR KIRCHNER: Sorry, yeah, this 6
is Walt Kirchner and I was asking Matthew's team about 7
at a higher level, have you identified targets of 8
opportunity that where you go through this, you'll 9
really see high pay off?
10 MR. HISER: Yeah sorry, so I think that 11 specifically what our high priorities -- we have a slide 12
-- I think in a few slides -- that covers exactly sort 13 of some of the specific high priorities that came out, 14 but to your higher level question, in terms of rolling 15 in things like GALL and PMDA and EMDA that sort of inform 16 aging management, what we were trying to focus on here 17 is where this harvesting meaningfully add new 18 information?
19 And like that second bullet on importance 20 of harvesting materials over laboratory aging, that's 21 something that we come back to, that's something that's 22 inspected or there's a lot of operating experience, 23 or it's easy -- take the PWSCC issue, right? There's 24 been a ton of crowd growth rate testing done on PWSCC.
25
26 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com And that doesn't mean we would not 1
consider, you know, looking at harvesting something 2
to confirm some of that with some actual plant aged 3
materials, but that would be a consideration if that's 4
a phenomenon that we feel like has been investigated 5
heavily, a lot of inspection footprint in the aging 6
management, you know, for susceptible materials.
7 But I would say a lot of that was brought 8
in with the knowledge of the staff and the provision 9
of, you know, license renewal and NRR, and then staff 10 and research that have been involved with developing 11 the GALL, the EMDA and PMDA reports over the last, you 12 know, 15, 20 years.
13 We sort of -- I don't know that we 14 explicitly sort of, you know, wrote down, but we were 15 building off that legacy and then looking at, how can 16 we -- what's the facet that harvesting can help us be 17 smarter, you know, fill areas where we'd like to have 18 a little more knowledge, a little less uncertainty.
19 Maybe that's helpful.
20 VICE CHAIR KIRCHNER: Yeah. You're 21 basically telling me you're using your corporate 22 knowledge and you know where these opportunities are, 23 here's the priority for sorting through --
24 MR. HISER: And when I say we I don't mean me, 25
27 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com or even me, Jeff, and Rob, but you know, 20 or 30 1
extremely knowledgeable and experienced staff across 2
the agency.
3 VICE CHAIR KIRCHNER: Well, maybe a little 4
bit more specific question along those lines. Do you 5
from a technical prioritization you looked for --
6 there's many more sophisticated models and a variety 7
of areas these days that could probably be I'll call 8
it calibrated to real plant data?
9 Do you look for those kind of opportunities 10 where say, this predictive tool could be so much better 11 if we could calibrate it to, you know, real plant data 12 versus, you know, aged in a lab data or whatever? Is 13 that input to your somehow?
14 MR. POEHLER: Yeah, I mean, kind of. I 15 mean, sometimes, you know, for example, we had -- there 16 was a ASME code case on prior growth rates for irradiated 17 stainless steels due to radiation, such as stress 18 corrosion cracking. So there was, you know, a model 19 there based on data that was available.
20 So that was based on real data, but then 21 you obtain more data through harvesting that showed 22 that those traits were potentially non-conservative.
23 So --
24 VICE CHAIR KIRCHNER: Well maybe we'll get 25
28 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com to it later. I'm thinking like the concrete stuff, 1
which like a good area where you could get out in front 2
of some of the concrete issues that we have, you know, 3
calibrating--
4 MR. POEHLER: You'll see that. That's --
5 (Simultaneous speaking.)
6 MR. POEHLER: Sorry. That's an important 7
part of our strategy, right? We're always trying to 8
-- because we have models for just about every 9
phenomenon, so we're always trying to test the limits 10 of those models and their applicability as we go to 11 higher and higher regimes that we're going to see later 12 and later in life. So that's a fundamental 13 consideration for all of the choices that we make.
14 MR. STAUDENMEIER: I was going to add, you 15 know, some of those models -- and Jeff was mentioning 16 one based on empirical data, others are first principle 17 models, and you're looking to, you know, harvesting 18 could help to, whether it's extending the window that 19 we sort of have verified, validated it, or established 20 in any window where it's really has some, you know, 21 relevant data. So yeah, we look for those 22 opportunities.
23 MR. POEHLER: Okay. So this slide 24 discusses our high priorities for metals, so there are 25
29 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com basically four, so the first one is Alloy 600 1
thermally-treated steam generator tubes with shallow 2
flaws. So the purpose of the --
3 MEMBER MARCH-LEUBA: Yeah, I'm confused.
4 Alloy 600 or 600 tubes?
5 MR. POEHLER: Tubes. But specifically, 6
thermally-treated.
7 MEMBER MARCH-LEUBA: Not a quantity of 600.
8 MR. POEHLER: Alloy 600 is the end.
9 MEMBER MARCH-LEUBA:
It really would be 10 complicated with 600 tubes.
11 MR. POEHLER: No.
12 MR. HISER: No, alloy.
13 MR. POEHLER: No. Yeah, we're falling 14 into nomenclature. We left the word alloy off in front 15 of that to save space.
16 17 But yeah, so you know, the purpose of this 18 testing would be to do NDE and mechanical testing to 19 establish structural integrity. Technical knowledge 20 to gain would be, you know, an assessment of basically 21 the accuracy of the ND that's performed in the field, 22 and also, you know, to how much structural integrity 23 is left in those tubes that have shallow flaws.
24 The status is we're seeking opportunities 25
30 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com to harvest these type of tubes.
1 The next one is thermally-aged 2
unirradiated cast stainless steel or casts, cast 3
austenitic stainless steel. We want that for fracture 4
toughness testing and microstructural testing.
5 Technical knowledge we would like to gain is basically 6
fractured toughness from real plant-aging conditions 7
to compare it to accelerated aging data.
8 You know, there's data generated at higher 9
temperatures than actual plant operating temperatures 10 on thermal aging, and we try to, you know, create an 11 equivalency to, you know, the temperature you would 12 see in a plant. The status were we have identified 13 and we're pursuing an opportunity for that.
14 The next one is the bottom mounted 15 instrumentation or BMI nozzles with known primary wood 16 or stress corrosion cracking indications. We would 17 like to obtain those for residual stress measurements 18 and also crack initiation and growth testing, and also 19 flaw characterization.
20 The knowledge we'd like to gain is to 21 confirm the adequacy of current inspection requirements 22 and confirm the NDE effectiveness of flaw 23 distribution. We're currently seeking opportunities.
24 There are few plants with known BMI indications.
25
31 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com And finally, prior fluence stainless steel 1
welds, and those are welds that have greater than two 2
DPA of neutron exposure. We want those to test for 3
fracture toughness, radiation assisted
- stress, 4
corrosion, cracking growth rates, and microstructural 5
characterization. The knowledge we'd like to gain 6
there is properties to inform inspection scope and 7
interval, and also flaw evaluation criteria.
8 (Simultaneous speaking.)
9 MR. POEHLER: Yeah. Okay. I know we are 10 looking at obtaining those materials through the SMILE 11 program, which I am going to talk about on a subsequent 12 slide, and some other opportunities.
13 CHAIR REMPE: I'd like to explore the one 14 about the bottom-mounted instrumentation nozzles. Is 15 the primary -- stainless steel and Inconel, or just 16 the stainless steel is what you're looking at that you 17 find on PWRs or the PWRs?
18 MR. POEHLER: Yeah, no, I think we're 19 looking more at PWRs that have Alloy 600 penetrations 20 and well, alloy 82, 182 welds. There's been some 21 operating experience with --
22 CHAIR REMPE: Does it matter?
23 (Simultaneous speaking.)
24 CHAIR REMPE: I mean, the different 25
32 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com designs Westinghouse had different than B and W and 1
is it just the Westinghouse ones, or?
2 MR. POEHLER: I --
3 CHAIR REMPE: Or CE ones?
4 MR. POEHLER: Yeah, no. I'm not sure.
5 It's probably Westinghouse designs. I don't know, 6
maybe Matt or Rob can come out then?
7 MR. TREGONING: I was going to say, I think 8
the real narrowing factor here is known PW 60 occasions.
9 I think there's maybe one, two plants.
10 CHAIR REMPE: Yeah.
11 MR. TREGONING: For which that's through, 12 and those plants are continuing to operate. They've 13 done repairs. So this is something that, you know, 14 would be applicable to all operating PWRs which have 15 Alloy 600, you know, and it's basically an analogous 16 situation to the upperhead, just a lower temperature.
17 So the presumption is it'll take longer 18 for the cracks to initiate, but the safety significance 19 is potentially high, and there has been some operating 20 experience.
21 You know, if one of those plants shut down 22 for instance, then at these indications, we would 23 certainly be, you know, interested in pursuing trying 24 to do some harvesting to get better knowledge about 25
33 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com that to inform, you know, aging management (audio 1
interference).
2 CHAIR REMPE: Thank you.
3 MR. POEHLER: So the next slide is similar 4
to the previous one but covering concrete and structural 5
and electrical high priorities.
6 The first one there is irradiated concrete.
7 You can see there's a lot of different testing that 8
we would like to do on that, and that includes in-situ 9
and in-service data for model verification, in-situ 10 NDE mechanical and microstructural properties 11 characterization, bench marking of structural damage, 12 and the potential, you know, for further irradiating 13 these materials.
14 The knowledge we'd like to gain there is 15 to, you know, reduce the uncertainties in models, 16 evaluating rate effects of in-service conditions versus 17 accelerating radiation, size effects. That is real 18 structures versus test specimens and a test reactor.
19 Evaluating concrete radiation and damage, depth, 20 gradiance and concrete bioshield, and to inform 21 structural integrity evaluation and inspection.
22 And we have identified and are actively 23 pursuing an opportunity to obtain irradiated concrete.
24 The next one here is reactor supports.
25
34 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com So we're interested in testing embrittlement, fracture 1
toughness and microstructural characterization. We'd 2
like to gain knowledge on structural integrity and 3
performance and inform inspection scope.
4 We have identified and are pursuing an 5
opportunity to obtain reactor support materials.
6 Then the last one is electrical cables, 7
both low and medium voltage. So we'd like to test to 8
compare service-aged specimens with accelerated age 9
specimens, and assess the effectiveness. Also to 10 assess fire spread and thermal failure criteria.
11 The knowledge we'd like to gain is the 12 confirmation of the technical basis for aging 13 management programs. We are currently seeking 14 opportunities to harvest cables.
15 MEMBER HALNON: This is Greg. Are you 16 looking exclusively for the cables at nuclear plants 17 or are you going to old fossil plants and other places 18 that may have similar aging issues?
19 MR. POEHLER: Nuclear, I believe. I think 20 we have -- some already done some. Do we have some 21 tech cable testing that we've done already?
22 (Simultaneous speaking.)
23 MR. TREGONING: I was going to make a note 24 on that.
25
35 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com I think the seeking opportunities is less 1
that it's hard to find them or we're struggling, but 2
maybe some of the other ones it's more, you know, 3
research programs require an area that, and in the 4
Division of Engineering area that are already ongoing, 5
and sort of we have an aspiration to get more, but we 6
don't necessarily have our research, you know, we're 7
not ready to go get them right now, they're more for 8
our research needs than it's so hard to find electrical 9
cables, you know, decommissioned.
10 MR. FURSTENAU: Yeah, it's Ray Furstenau.
11 And I was going to say because I mean, there's a lot 12 of old fossil plants that aren't being used right now, 13 50, 60, 70, sometimes 80, 90 years old, so.
14 MR. TREGONING: Yeah. We have a slide 15 coming up that talks about sort of what we've done and 16 we have harvested cables before. The other comment 17 I just wanted to make on the priorities overall is just 18 kind of harping back to what Rob's point was earlier, 19 that you'll notice that these are just our high 20 priorities, there are, you know, medium and low 21 priorities.
22 But you'll notice there are no RPV, reactor 23 pressure vessel components on here, and it's for the 24 exact reason Rob was mentioning, the surveillance 25
36 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com program.
1 There's just a much greater level of 2
knowledge of those materials, obviously their safety 3
standards is very high. But we felt like the unique 4
contribution for harvesting is it's harder to sell and 5
justify it, so on that, particularly on a couple of 6
those criteria, any RPV materials end up being 7
downgraded so they just don't end up bubbling up to 8
the very top. I just wanted to kind of make that higher 9
level point.
10 MR. POEHLER: Now I am going to touch 11 briefly on previously harvested materials, so the NRC 12 staff have catalogued the previously harvested 13 materials from prior NRC sponsored research. That 14 includes at PNNL we have a large array of components 15 penetrations up to large piping sections, so we're using 16 NDE research.
17 Battelle, we have some large primary system 18 piping in all those, and Argonne National Lab we have 19 smaller reactor internals materials, irradiated 20 reactor materials.
21 Some of the other sources of previously 22 harvested materials are the Department of Energy 23 Nuclear Fuels and Materials Library. Also Studsvik 24 with the SMILE related and other harvested materials.
25
37 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com And also the Halden Reactor Project.
1 This is basically showing a little snippet 2
of the column headings from the joint harvesting 3
opportunities table that NRC has worked with EPRI to 4
develop. It covers both domestic and international 5
harvesting opportunities for both plants that are 6
decommissioning now or have announced shutdown dates.
7 And this is just providing examples of the headings 8
for the columns and what types of information.
9 So in addition to all the basic plant 10 information and operating conditions, you have for the 11 various components, you know, specifically, you know, 12 materials, environment, in terms of
- fluence, 13 temperature, and water chemistry. You have that for 14 each type of component, and these are some of the ones 15 obviously they were interested in the RPV, although 16 I'll just mention that we're less interested in that 17 in general.
18 RPV had penetrations and its baffle plates 19 internals bolts and of course shroud and barrel welds, 20 so these are just examples. There's more, different 21 categories of components in the table.
22 MR. TREGONING: Okay. Can I ask --
23 MR. POEHLER: Go ahead.
24 MR. TREGONING: Yeah, we had a question 25
38 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com earlier about documentation.
1 So this table was really developed, or 2
we're developing it because it's a living table in 3
conjunction with industry, try to not only identify 4
the plant, the characteristics of the plants and 5
materials that are out there now so we understand their 6
attributes, but also to make the plant owners aware, 7
hey, this is the information that we want from a 8
harvesting perspective, because I think what we found 9
when they go into decommissioning, a lot of times it's 10 the documentation that's the first thing that's 11 disposed of.
12 So, getting that documentation, getting 13 knowledge from the decommissioning companies and plant 14 licensees of the types of information that we want, 15 we tried to distill it down for this spreadsheet table 16 that we've got so that we can be more sort of reactive 17 when we find out a plant's closing down. You know, 18 if we want to identify if there are any opportunities 19 we could go to the licensee of the decommissioning 20 company and say here are the things that we would like 21 to understand if you have this information.
22 MR. HISER: Yeah, and I'll just add from 23 a little more of a practical note, we have not had as 24 much success being able to populate this spreadsheet.
25
39 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com I think in an ideal world for every plant in the U.S.
1 and even internationally, you know, we'd like to have 2
as much of these columns out, and then we could sort 3
of look at dates, look at logistics, you know, and also 4
most importantly, look at where our priorities and which 5
one would best address it.
6 In practice it's hard to get all of this 7
information even for one plant. It requires a lot of 8
digging into records that we don't have access to 9
necessarily. You know, you can get some from an FSR 10 but you're not going to get all of this, especially 11 on the environmental conditions, DPAs, temperatures, 12 for specific components.
13 So we've not had as much success but EPRI 14 has continued to kind of push on industry, make this 15 a priority with them. In fact, just in the last I'd 16 say six months to a year, they said they're going to 17 continue trying to press their members to provide input.
18 We got a lot of information actually from 19 the Swedish plants that are involved in the SMILE 20 project because they're doing a lot of harvesting and 21 they dug up a lot of that information.
22 But we do think this is a good tool. We 23 haven't been able to maybe make it as effective as we 24 hoped because we're lacking the ability to populate 25
40 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com it as well as we can but I think it's a good framework 1
that hopefully we can build on and populate over time.
2 CHAIR REMPE: How willing are the 3
decommissioning companies to provide the information?
4 Because you said that's one of the first things they 5
destroy. Are they willing to share?
6 MR. TREGONING: It depends on the 7
decommissioning company. And I think Matt talked 8
earlier, this is not their prime business objective.
9 And so finding a willing partner that is engaged in 10 harvesting, that's a very difficult challenge.
11 And I would also just add it depends how 12 the decommissioning's progressing. You know, some of 13 these plants, the utility that operated the plant is 14 just selling the plant.
15 CHAIR REMPE: Right.
16 MR. TREGONING: You know, Palisades, for 17 instance, Holtec, do not operate the plant, they bought 18 the plant from Entergy. Now they're trying to see if 19 they can restart it, but, you know, Holtec's not really 20 in the business of operating nuclear plants, they're 21 in the business of really nuclear waste canisters, and 22 you know, doing other parts of the nuclear business.
23 But, so, you know, or energy solutions, 24 for instance, is really just decommissioning. So, it 25
41 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com gets handed off. We really don't have knowledge of 1
that decommissioning company to really operate a plant, 2
and all of this is really operating plant kind of stuff.
3 CHAIR REMPE: So when you said it's 4
destroyed, my mind immediately thought that Holtec or 5
some company like them would be the ones that would 6
be first to destroy it. What you're saying is actually 7
the plant before they sell to the decommissioning 8
company might destroy it?
9 MR. TREGONING: And maybe destroy it. Let 10 me amend my remarks. Maybe destroy is too strong a 11 word there. It becomes unavailable for a variety of 12 reasons.
13 CHAIR REMPE:
From the plant 14 owner/operator, not the decommissioning company?
15 Because that's what I thought, oh, the decommissioning 16 company --
17 MR. TREGONING: Right. And -- well, but 18 if the decommissioning company comes in and there's 19 no plant people that are still working, the 20 decommissioning company has no idea where to find that 21 information.
22 MR. FURSTENAU: Yeah, it was not 23 maintained.
24 CHAIR REMPE: But you got to catch it, and 25
42 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com it's --
1 MR. TREGONING: And it depends on the plant 2
because some plants, Westinghouse archives a lot of 3
that information. So then you have to go back to 4
Westinghouse to try to get it, and/or whoever the 5
original vendor was, and that can be challenging as 6
well because even though it's technically available, 7
finding it can be a bit of an archaeological challenge.
8 MR. FURSTENAU: Or it depends on the 9
component and how the internals, typically all the 10 fabrication records weren't handed over to the plant 11 to the internals. And the vessel, they would've been.
12 You know, so if you're trying to harvest internals, 13 you're probably back at the vendor, Westinghouse CE, 14 digging into their records, and yeah.
15 MR. TREGONING: It's totally a potpourri.
16 MR. FURSTENAU: Yeah, it just varies.
17 (Simultaneous speaking.)
18 MR. TREGONING: The plant --
19 (Simultaneous speaking.)
20 MR. TREGONING: Yeah, and where you come 21 from the decommissioning process.
22 MEMBER SUNSERI: Not to belabor the 23 discussion but I think of it coming down to these are 24 all construction records that are required to be 25
43 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com maintained for the life of these facilities, so what's 1
the definition of life of the facility? When they 2
declare that they're shutting down or when it gets fully 3
decommissioned? I don't know the answer to that.
4 MR. HISER: Don't quote me but I think it's 5
when they defuel and send a notification to the NRC 6
that they removed fuel from the core and they're not 7
-- and I think they can start to relax. Then once their 8
fuel --
9 MEMBER SUNSERI: Well, that would be 10 interesting then because maintain means retrievable 11 and in a form that you can use, right?
12 MR. HISER: Yes.
13 MEMBER SUNSERI: Okay, I got it, thank you.
14 MR. POEHLER: Okay. So this is just a list 15 of recent current harvesting activities. I'm not going 16 to read these, but a lot of them do have published 17 reports here that we provide links for, and you know, 18 a couple that I just want to highlight are the Zorita 19 reactor controls work, which is pretty recent. And 20 also the Ringhals and Oscarshem 2. The two bottom rows 21 were they're ongoing through SMILE, so we're going to 22 talk about that more on a subsequent slide.
23 So this slide kind of a bit summarizes the 24 previous slide, but some of our recent and current 25
44 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com activities include neutron observer materials from 1
Zion, reactor internals from Zorita, and the various 2
metallic components through the OECDNEA Studsvik 3
Materials Integrity for Life Extension, or SMILE 4
project.
5 We are in addition pursuing additional 6
opportunities for more targeted harvesting from 7
domestic and international plants. That's focused on 8
high value components in alignment with the NRC 9
priorities, and we're working cooperation and 10 coordination with DOE and EPRI.
11 And finally the SMILE project. The basic 12 objective is harvesting characterization and testing 13 of metallic components from decommissioning Swedish 14 BWR and PWR plants.
15 Some of the components of interest are 16 reactor pressure vessel low alloy steels, stainless 17 steel internals such as the core shroud barrel, core 18 barrel welds or shrouded barrel welds, I should say, 19 baffle plates, baffle bolts, nickel alloy penetrations, 20 piping and steam generator tubes. The reactors that 21 are within the scope are the Ringhals 2 reactor, which 22 is a Westinghouse 3 loop PWR with around 30 effective 23 full power years.
24 Of interest is the Alloy 690 and Alloy 52 25
45 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com weld metal from the world's second oldest replacement 1
steam generator, which was replaced in 1989. And the 2
oldest replacement RPV head, which was installed in 3
1995.
4 And the second reactor's Oscarshem 2 and 5
ABV Adam BWR, where they're on 30 effective full power 6
years. And the SMILE program is a highly leveraged 7
program for NRC. There are eight countries 8
participating, along with EPRI in the U.S., so it's 9
a good value.
10 And at this point, I'm going to turn it 11 over to Matt Hiser to present the remaining slides on 12 I think concrete and electrical. Matt?
13 MR. HISER: Okay, thanks. Thanks Jeff.
14 And hopefully my voice will hold out, if it doesn't, 15 I know Rob can carry us to the finish line. I also 16 just wanted to caveat that I am more of a metals guy, 17 like Rob and Jeff, we do have some of our colleagues 18 in concrete and electrical areas.
19 If you guys have more specific technical 20 questions on the drilling down, I'll have to phone a 21 friend, but I think I have enough working knowledge 22 to sort of present these.
23 This slide cover's concrete harvesting, 24 and like the prior couple slides ago, we've had to sort 25
46 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com of capture recent current activities and then for where 1
we're going moving forward in each of these areas.
2 So the main recent activity in the concrete 3
harvesting was that some unirradiated concrete cores 4
from the SONGS, San Onofre Nuclear Generating Station, 5
were removed.
6 We've got a reference to the research 7
information letter that documents this. And there was 8
some investigations now, particularly looking at the 9
mineralogy and the irradiation level on this concrete 10 to assess how valuable it would be to look at irradiated 11 concrete from SONGS.
12 Based on what was found, I have a little 13 more on the next slide, but basically the conclusions 14 from that is that they do think they'll be looking at 15 irradiating concrete from SONGS would be of value.
16 So, that's sort of documented and discussed in that 17 research information letter that was published I think 18 maybe six months ago.
19 And then also, you know, just sort of to 20 build on that, staff is looking at, you know, actively 21 pursuing an opportunity to harvest irradiated concrete, 22 and that will help us understand radiation effects on 23 concrete performance. So this will be looking at 24 irradiated concrete from biological shield structure 25
47 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com that is closest right outside the vessel wall reactor 1
vessel.
2 Looking to do some in-situ NDE testing, 3
as well as, you know, physically remove large sections 4
and do laboratory research looking at mechanical 5
- testing, microstructural characterization, 6
benchmarking the damage progression against the plant 7
data to the point of, you know, sort of verifying and 8
validating models, and then even potentially looking 9
at further radiation.
10 So, maybe Jeff can help with this?
11 MEMBER HALNON: So, this is Greg. The 12 concrete, I mean, irradiation's important but we have 13 two plants out there that have concrete issues, but 14 it's not irradiation. Are you connected with that 15 program as well? Davis-Besse and Seabrook?
16 MR. HISER: Yes, and I know our concrete 17 folks are well aware of ASR issues as well. I believe 18 and I'll get out of my depth really quickly but it has 19 to do with a type of aggregate, I believe.
20 MEMBER HALNON: Right.
21 MR. HISER: And --
22 MEMBER HALNON: But the testing piece, it 23 just seems like, you know, concrete testing program, 24 you know, because you're doing intensive stress and, 25
48 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com you know, compressive, that sort of thing. Is that 1
all one testing program? I mean, one testing group 2
so they have this conglomerate of knowledge about 3
concrete issues, or is it fragmented in some way?
4 MR. HISER: Yeah. No, and we've got our 5
SMEs. Yeah, we have a concrete group that this is what 6
they deal with and --
7 MEMBER HALNON: Okay.
8 MR. HISER: And we've had other projects 9
that have looked at concrete pathologies, including 10 the alkali-silica reaction or ASR, as well as other 11 pathologies. So --
12 MEMBER HALNON: It's the same materials 13 people?
14 MR. HISER: It's the same materials 15 people. So and --
16 MEMBER HALNON: Okay, that's what I was 17 curious about. And are we, you know, collating that 18 experience into one group?
19 MR. HISER: Yeah. So when the concrete 20 folks develop their priorities, they had knowledge of 21 all these other programs that they've done in the past, 22 as well as operating experience and needs, and they 23 went through the same exercise as the metals folks did, 24 came up with their priority lists.
25
49 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com MEMBER HALNON: Okay.
1 MR. HISER: So yes. And we've got a couple 2
of them on if we need to phone a friend.
3 MEMBER HALNON: Okay.
4 MR. HISER: Okay.
5 CHAIR REMPE: Just out of curiosity, I 6
mean, there's different types of concrete, salt based 7
and things like that, and in your prioritization, I 8
assume both types are a concern, or maybe one type is 9
of more concern, or?
10 MR. HISER: Yeah, I think -- let's ask 11 Madhumita or Jose. Do you want to respond to that?
12 I know my short answer would be yes, but let Madhumita 13 answer it.
14 MS. SIRCAR: Okay. Yes, Madhumita 15 Sircar, I'm from the concrete side. Yes, one type is 16 more important than the other, like the BWR usually 17 at accumulative fluences and the second structure is 18 different. PWR, two loops, and three loops accumulate 19 higher fluence and sometimes the reactor is supported 20 directly on the biologic shield wall, which is very 21 close to the reactor pressure vessel, so that gets 22 higher accumulated fluence, and also performing of very 23 important support performance.
24 So, basically not all plants are equal, 25
50 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com PWR plants are more important, two loops, three loops, 1
four loops, the accumulative fluence is lower than two 2
loops and three loops, but still it's higher than the 3
4 CHAIR REMPE: What I was curious about was 5
there's like the salt base -- when we talk about molten 6
core concrete reactions, there's different types, and 7
to my knowledge, BWR or PWR won't pick based on type 8
of concrete because they are that type of plant, it's 9
where they're located and what they can get nearby.
10 And does it seem to matter what type of concrete, is 11 what I'm asking?
12 MS. SIRCAR: Yes.
13 CHAIR REMPE: And that also --
14 (Simultaneous speaking.)
15 CHAIR REMPE: What you find is the most 16 susceptible?
17 MS. SIRCAR: Type of concrete was if it 18 is the more silica bearing -- then it was more 19 susceptible for radiation related degradation.
20 CHAIR REMPE: Thank you.
21 MR. TREGONING: Maybe I'll just add onto 22 that, so you're right. A lot of these pathologies are 23 aggregate sensitive, so not only in the U.S. but 24 internationally we've developed aggregate maps for 25
51 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com where the plants are located and what type of quarries 1
were nearby so we have an understanding of the basis 2
of the aggregate. And that's something that our 3
concrete experts look at, not only for U.S. programs, 4
but international
- programs, to see what the 5
applicability is in a particular study, to what swath 6
the U.S. claims.
7 So understanding local site conditions is 8
of upmost importance to try to figure out again what 9
the applicability, and what the particular degradation 10 concerns are because again each of the aggregates have 11 different pathologies that they're susceptible to.
12 CHAIR REMPE: Thank you.
13 MR. HISER: And I'll try to keep us moving 14 forward. This slide sort of summarizes the key 15 findings from that research information letter from 16 the SONGS unirradiated concrete, and the focus of this 17 was to get someone in concrete to confirm that we have 18 the type of aggregate of they've seen significant 19 radiation effects, which as Madhumita just mentioned, 20 is silica bearing.
21 And so you can see in this figure here that 22 the silicon image, you know, is lit up pretty well so 23 he sort of confirmed what they found, what they thought 24 they were going to find based on the local mineralogy 25
52 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com and the records they had.
1 But this gets us sort of the digging into 2
the records. You know, this was a relatively small 3
expense to look at unirradiated concrete, confirm now, 4
you know, hopefully later on in the decommissioning 5
process they'll be able to get some irradiated concrete 6
at the time. At the time based on decommissioning is 7
right to do that.
8 MEMBER BIER: Excuse me, a quick 9
follow-up question. On the aggregate, is that 10 something that would've been recorded at the time the 11 plant was built, or it's just guesswork after the fact 12 because the data was not gathered at the time?
13 MR. HISER: I'll offer -- yeah, let's Mita 14 respond to that in terms of what construction --
15 MS. SIRCAR: Yes, for this particular 16 plant, we worked with SONGS, the owner, and they have 17 some specification from the construction time, and also 18 they identified their source of the aggregates, so from 19 that and as Rob mentioned earlier with the geological 20 mapping around that area and the source, so we have 21 the combination of both.
22 MR. HISER: All right, moving on from 23 concrete to harvesting for fire research. And we've 24 got a couple of recent and current activities to 25
53 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com mention, and these were noted in the slide a few slides 1
back, the table summarized all the activities.
2 So there were electrical enclosures that 3
were removed, and I believe there's a couple of NUREGs 4
that are cited back in that table.
5 We're looking at fire detection to keep 6
release rates and electrical enclosure fires, and then 7
more recently there's been electrical bus ducts 8
harvested from Zion a few years ago, and actually just 9
this year, really just in the last few months from 10 Crystal River 3 if you look at high energy arc fault 11 testing on most representative samples.
12 So got a couple more slides that sort of 13 touch a little bit more on the HEAF testing. And then 14 moving forward, fire research area they are looking 15 at opportunities to probably look at and try to acquire 16 aged electrical cables. And I think the focus is sort 17 of accessing fire resistances decreasing over time due 18 to aging. But that's something that has not started 19 or yet.
20 So this research I think is a good example 21 of how important it is to - and Ray talks about this 22 all the time -- it's important for the Office of Research 23 to be ready. So with this one, this is actually, you 24 know, we talk about how long and important and complex 25
54 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com harvesting is.
1 With the fire research, we got a call from 2
a fire brethren, they had a small window, they could 3
add some test materials and for some testing that was 4
ongoing in August. I think they called us in maybe 5
May, April or May. And said, can you get us some 6
materials from harvesting? Can we get some harvested 7
materials to add to this test measure?
8 Matt and I looked at each other and said, 9
there's no way. But then we'd had enough contacts that 10 we started making calls both infernally and the agency 11 next to her.
12 I think within two weeks, we'd identified 13 materials and because they were not irradiated, they 14 were, get those materials, get them to the NRC test 15 facility, and they've actually been tested, so it's 16 probably the best example of the shortest, least 17 expensive, carefree harvesting activity we've ever 18 pursued at the NRC.
19 Again I think that's sort of testament to 20 the fact that we were planful and we were ready for 21 that opportunity when it came, and it allowed us to 22 act quickly on it, and that I believe is really the 23 essence of what we're trying to do with this harvesting 24 program.
25
55 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com All right, the next couple slides just dig 1
a little more into the HEAF testing. If you have real 2
specific HEAF questions I'm going to very quickly pass 3
it along, but I'll just try to touch on this a little 4
bit, and you guys may have more familiarity because 5
I think you guys have a lot of attention on it recently, 6
but NRC's the operating agent of an OECDA agreement.
7 That covers 21 tests jointly sponsored with NRC and 8
eight other countries. Just in this year ten medium 9
voltage tests were performed and eight of them were 10 performed on medium voltage non-segregated bus duct.
11 Recent research in a draft NUREG shows that 12 many of these have a zone of influence that may be 13 larger than what was originally proposed in previous 14 guidance, supplement 1, the NUREG-CR6850. And so these 15 tests provide valuable data to evaluate those models 16 and assess the HEAF hazard in medium voltage equipment.
17 Next slide.
18 This is one of the more fun slides with 19 little pictures before and after. So we're just going 20 to kind of focus on the tests on these harvested 21 materials which were from Crystal River. There were 22 two sections of three phase five kilovolt 23 non-segregated bus ducts that were acquired from 24 Crystal River. They were all aluminum bus ducts and 25
56 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com bus bars.
1 Three conductors per phase. And these 2
ducts were used to complement six other ducts that were 3
procured new, and so they, you know, sort of answer 4
the question of what's representative of, you know, 5
what's in a real plant versus something that you buy 6
new today. And all eight of these were tested in the 7
same manner and measured for their response.
8 And the next bullet there touches on the 9
test parameters for four kilovolts, 30,000 amps, and 10 then two or four second pulse time. And then the --
11 and I'm not qualified really to speak of the technical 12 details of what's the results showed, but our colleagues 13 working on this in individual risk analysis and research 14 said that in their view, the preliminary results show 15 that the models are reasonably predicting the hazards.
16 They sort of confirmed what they expected to see based 17 on their models.
18 And you know, the pictures are really I 19 think, you know, enlightening. Hopefully we got a good 20 kind of before and after, you see what it looked like, 21 and then what it looks like after the fault.
22 MEMBER SUNSERI: Is there any appreciable 23 difference between the new ones that were tested and 24 the older ones?
25
57 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com MR. HISER: Gabe, do you want to comment 1
on that?
2 MR. TAYLOR: Sure, can you hear me all 3
right?
4 MR. HISER: Barely.
5 MR. TAYLOR: All right. My name's Gabe 6
Taylor with the Office of Research and there were 7
definitely differences. It seemed that the new bus 8
ducts were better material, the fasteners were 9
smaller, the stuff that we harvested seemed to be just 10 more robustly built. You know, as far as, you know, 11 comparison from a thermal effect there really wasn't, 12 you know, too much difference that we saw with that 13 regard.
14 MEMBER SUNSERI: Thank you.
15 MR. HISER: Thanks Gabe. We just have one 16 more kind of technical area to talk to you on and then 17 I got about two or three sort of wrap-up slides, broader 18 wrap-up slides.
19 So this is touching on harvesting for cable 20 aging research. The main ongoing current activity is 21 looking at loss of a coolant accident test on electrical 22 cables and this includes some cables that were harvested 23 at the Zion plant, being aged within like 50, 60, and 24 80 years of operation. This was also noted in that 25
58 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com earlier table.
1 I don't believe there's any final results.
2 I belie they're getting close, maybe within the next 3
year. And I don't want to promise for my colleagues, 4
but I think that was the comment they said, they're 5
getting pretty close to finishing up that program and 6
having, you know, a final report to share.
7 And then moving forward, we are looking 8
at opportunities to engage with external stakeholders 9
and identify harvesting opportunities representative 10 of cables in U.S. plants. We had a bit of dialogue 11 with EPRI on this. The likelihood that EPRI and DOE 12 and NRC will work together to harvest some more 13 materials. I'm particularly looking at validating NDE 14 techniques, and whether they can effectively track 15 cable degradation, and then also looking at aging 16 management and environment qualification on aged 17 cables.
18 MEMBER MARCH-LEUBA: Are you concerned 19 about neutron damage or radiation damage, or 20 atmospheric, oxidation on the sides of both?
21 MR. HISER: Yeah, I think it can be any, 22 radiation, wetting, temperature. There's a variety 23 of different mechanisms.
24 MEMBER MARCH-LEUBA: So you haven't --
25
59 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com have the -- so that's where the previous comment that 1
you can get a 100 year old plan (phonetic) cables out 2
there, which you probably cannot buy at Home Depot 3
anymore because they're completely different 4
materials.
5 MR. HISER: Right. Yeah, and that gets 6
to one of the unique pieces that we didn't touch on 7
earlier, but that's one of the other values of 8
harvesting, is you know, getting the vintage 9
fabrication process, which they'd be better in some 10 ways working more robust, you know, maybe not as good 11 materials depending on the situation, you know. So 12 yeah, that's all part of the thinking here.
13 MEMBER SUNSERI: Sometimes on the cables, 14 the area of interest is where they've been spliced.
15 Maybe you get vices for those things?
16 MR. HISER: Mo, do you want to chime in, 17 or we'll phone a friend one last time hopefully.
18 MR. SADOLLAH: Sure. Can you hear me 19 okay?
20 MR. HISER: Yep.
21 MR. SADOLLAH: Okay. Yeah, this is Mo 22 Sadollah, research at Electrical and IC Branch. So 23 the material that we got, you know, they were from Zion 24 mostly, the ones that we could use. We got some from 25
60 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com Crystal Rivers, but they were not long enough, and we 1
were able to take them. They were about 20 years old 2
but we were able to accelerate, age them to about 50, 3
60, and 80 years again and test them, run them through 4
a LOCA, and that was just completed.
5 And the question was -- I'm sorry, can you 6
repeat the question again just to make sure I don't 7
miss anything?
8 MEMBER SUNSERI: This is Matt Sunseri.
9 My experience a lot of times on these cable aging 10 management, the concern or the area of interest is where 11 the cable has been spliced.
12 MR. SADOLLAH: Yes, that's a great point 13 because you might've heard or you might know that most 14 electrical cable
- issues, damages occur at 15 determinations and splices. So far we have not been 16 able to gather any samples of the spliced cables. But 17 no, that's a good idea.
18 That's one thing that we also have on our 19 radar, to look more, and so far our cable research has 20 been focusing on the cables pretty much. Going 21 forward, we are kind of also including in that research 22 and that understanding the area of splices and 23 terminations on both ends of the cable. And we have 24 not been able to procure a spliced, aged, or naturally 25
61 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com aged sample yet. Hopefully in the future we might be 1
able to put our hands on some.
2 MEMBER SUNSERI: Thank you.
3 MR. SADOLLAH: You're welcome.
4 MEMBER BIER: One other question. Kind 5
of touched on on that last slide indirectly, I assume 6
that a lot of these materials, or at least some of the 7
more important ones, would've been subjected to 8
accelerated life testing back when they were first 9
selected and installed. And has there been a 10 comparison to say how the accelerated life testing 11 compared to the real world experience? Is it mostly 12 pretty consistent or can it be wildy far off?
13 MR. SADOLLAH: That's also a good 14 question. This is one of the objectives of the research 15 we're doing, to see if you put a cable accelerate aging 16 in a laboratory environment basically, does it really 17 simulate, is it correlatable to aging that takes place 18 naturally in the field, in the containment, let's say?
19 That's one of the things we're looking at 20 right now as a part of this research, and going forward, 21 we'll probably look into that even a little bit more 22 in details. But yeah, now the cables that we normally 23 would find if they're AQ qualified cables, they would've 24 been type tested before.
25
62 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com In other words, a section of similar cable 1
manufacturer and type and
- vintage, had been 2
accelerated, aged, and tested through LOCA, but the 3
cables that are installed themselves, no, they have 4
not been accelerated, aged as they were just, you know, 5
taken off the reel, installed, and they've been in that 6
environment like for Zion about 20 years in the 7
containment, and then we looked at it and tested it, 8
and then we kept even aging it further.
9 MR. TREGONING: I just wanted -- Rob 10 Tregoning -- I just wanted to expand. Great question, 11 Member Bier. That's something in all of our programs 12 we're concerned with comparing actual aging versus 13 accelerated aging because it doesn't matter if it's 14 metal, concrete, electrical, or cables, that's always 15 a fundamental consideration so that's one of the 16 principle things that we're trying to understand and 17 achieve with the harvesting program.
18 MR. BLEY: Rob?
19 MR. TREGONING: And I was -- go ahead, Mo.
20 MR. BLEY: This is Dennis. What'd you 21 say? Are there any cases where you've actually made 22 that comparison and can you tell us anything about the 23 result? Or is it just something you want to do?
24 MR. SADOLLAH: Like I said -- the only 25
63 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com cables, samples that we were successful in getting and 1
testing were designed on cables. We had some cables 2
from Crystal River but they were not long enough, we 3
couldn't do much with them. Now these cables were only 4
I guess I should say 20 years old.
5 At 20 years of natural aging in plant 6
environments, they actually do not go through that much 7
of polymeric material changes. You do see some 8
exhaustion of the antioxidants and some changes of 9
filler material, but what we found is that the polymers 10 or the rubber material themselves, they don't age in 11 that short period of time.
12 So what we have seen so far, obviously there 13 is no samples out there that's 80 years to compare with 14 the 80 year old accelerated age samples that we have, 15 so not even, you know, we have some information about 16 50 year old samples accelerated age, but we don't have 17 good samples of cables that are aged even further.
18 The thought process is, and we're still 19 looking into it that, yeah, one main difference between 20 accelerated aging is typically all these cables, they 21 were qualified by exposing them to radiation and thermal 22 aging separately whereas in the plant they see radiation 23 and heat simultaneously. So whether or not there's 24 a synergistic effect, what we found preliminarily --
25
64 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com and that report is going to come out next two or three 1
months -- the preliminary finding is that it really 2
depends.
3 Some material aged faster, better, or go 4
through more degradation by being aged simultaneously, 5
and some material don't show much difference whether 6
they're aged sequentially, radiation first and then 7
thermal.
8 So, the preliminary finding long story 9
short is that there's not that much difference between 10 how they're aged and how they are naturally aged in 11 service environments, but we're still looking into more 12 and it seems to be it's material dependent.
13 VICE CHAIR KIRCHNER: That's a real good 14 answer on cables. If I heard Rob correctly, he was 15 talking about other kinds of areas where the same kind 16 of -- you'd like to make the same kind of comparisons, 17 and Rob, are there any cases in mechanical equipment 18 and the like that have had that comparison done?
19 MR. HISER: Yeah, this is Matt Hiser.
20 I'll speak to the Zorita internals experience which 21 is a significant program we've done over the last ten 22 years or so, and I've recently put out a couple reports.
23 But I'd say it's similar to Mo, you know, that it's 24 a mix.
25
65 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com In some areas, we've sort of confirmed what 1
other data was showing, but in some areas, you know, 2
our prior understanding to be non-conservative in a 3
couple areas.
4 So for instance with stainless steel plate 5
material, at low fluence levels we've pretty much 6
confirmed what we've seen before, low representing ten 7
to 20 DPA. At fairly high fluence levels above 20 DPA, 8
the materials we harvested tended to show a bit more 9
susceptibility to rapid crack growth rates, but really 10 no difference or not much difference in embrittlement.
11 So it depends a little bit on the properties and the 12 fluence levels you're talking about.
13 The other example is the stainless steel 14 welds that we tested, which is really focused on 15 embrittlement and fracture toughness.
16 It showed that they embrittled at a higher 17 rate and an earlier or lower dose, so industry had some 18 guidance that was being used, disposition flaws, 19 looking at -- and this has been discussed in public 20 meetings and has been looking at by EPRI and is being 21 addressed by industry, but some of that data showed 22 that basically these materials would embrittle to a 23 greater degree at a lower level of fluence than was 24 previously anticipated.
25
66 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com So, you know, I think harvesting is 1
helping us but to Rob's point, in most of these areas 2
there's some data. It may be less representative, it 3
may be accelerated aging, you know, it may be a separate 4
thermal and radiation, you know, aging to replicate 5
it, and we're now getting what we think is a more 6
representative and a more true answer, and so we're 7
trying to have that guide us.
8 Some cases it says that the previous 9
research, you know, is spot on, in other cases it's 10 showing us new things.
11 VICE CHAIR KIRCHNER: Very interesting, 12 thanks.
13 MEMBER SUNSERI: So Matt, I hate to 14 interject here, we've got 15 minutes left on this 15 session, so. I believe you're doing a good job of 16 responding to their questions, but I just want to be 17 mindful of the time.
18 MR. HISER: Okay.
19 MEMBER BIER: One more quick follow-up.
20 It sounds like with that inconsistency of the answers, 21 it really means that kind of the basic science of what's 22 going on aging is not really well understood yet and 23 we may be getting some clues out of these comparisons.
24 Is that --
25
67 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com MR. HISER: Correct, and I think you've 1
got to be careful in all of these, and in our analysis 2
of these results, for instance, we try to be careful 3
because, you know, in metals and I think in most 4
materials, there's heat to heat, or you know, a 5
fabricated variability, so if you've looked and you 6
think it's a more representation, but it's also just 7
one heated material, and maybe you're comparing it 8
against eight or ten other heats that have been studied 9
in a less representative way.
10 So you don't want to go overboard and say, 11 well this is, you know, the gospel truth, but you also 12 don't want to, you know, dismiss it because it is --
13 we are doing this because we think it's a more 14 representative aging. It is stuff right out of an 15 operating plant.
16 So, you know, we try to walk that line and 17 then if we find a discrepancy, then maybe that's a reason 18 to say let's maybe try to harvest one or two more, and 19 confirm or, you know, refute what the prior harvesting 20 showed.
21 MR. TREGONING: Rob Tregoning. Just 22 wanted to add quickly. So the thing that we're really 23 knowledgeable about, like a lot of scientists and 24 engineers, we try to understand and conduct separate 25
68 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com effects testing. Right? Just like you do in thermal 1
hydraulics and other areas, right? You try to 2
understand the physics associated with the separate 3
effects.
4 It's the combined or integral or 5
synergistic -- I won't even use the term synergistic.
6 It's those combined effects that are more challenging 7
to replicate in the lab, and that's what we really get 8
out of the harvested materials.
9 So that's what ultimately makes them so 10 valuable. It allows us to assess those things that 11 are very challenging to accurately recreate in the lab.
12 And depending on the mechanism, we get an understanding 13 if these combined effects are important or not.
14 And that's incredibly valuable from my 15 perspective at the end of the day, regardless if you're 16 talking about metals, cables, or concrete.
17 MR. HISER: Okay, just about three slides 18 I think to wrap up.
19 So this slide is focused on harvesting 20 outreach, and I know Member Sunseri I think was at this 21 meeting -- maybe others as well -- but NRC held a public 22 meeting titled status of NRC harvesting activities in 23 late June, and we used this as an opportunity to update 24 the public on NRC harvesting activities and receive 25
69 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com feedback from stakeholders.
1 This meeting featured presentations by the 2
NRC staff, partly myself, as well as representatives 3
from a couple different labs at DOE, Idaho National 4
Lab, Oak Ridge National Lab, staff from EPRI, the 5
Electric Power Research Institute, a
couple 6
international organizations, Studsvik and actually 7
Vattenfall, which is the operator of the Ringhals plant, 8
that is participating and are providing a lot of the 9
materials for the SMILE program.
10 A very interesting perspective from an 11 international utility, and then finally Beyond Nuclear 12 gave a presentation. And we did just want to highlight, 13 you know, we're part of taking input, incorporate it 14 in whatever way we can.
15 One piece of feedback that we received from 16 this public meeting was to look at risk from internal, 17 external events and non-safety related components.
18 Oh, for example, flood penetration seals 19 on doors and other components that may have risk 20 significance to them relative to external flooding, 21 and that is something that we have discussed internally 22 but I think based on that feedback, we are 23 reinvigorating our efforts, and have actually started 24 having some discussions with the Department of Energy 25
70 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com DOE lab staff at looking at opportunities to harvest 1
from some of the plants where we're already doing 2
harvesting, we already have that relationship with the 3
utility.
4 So we just wanted to kind of highlight that, 5
you know, this was an example of something that we were 6
able to take away from this public meeting. That was 7
feedback from external stakeholders that we're trying 8
to take to heart as we continue down the harvesting 9
path. Next slide.
10 And then just touching on harvesting 11 partnerships, as we mentioned earlier, leveraging 12 cooperation we think are very important. Harvesting 13 is expensive. To be honest I don't know if there's 14 a single example or maybe just one -- there's fairly 15 few examples, particularly on irradiated materials 16 components where NRC has done it by itself.
17 It's just very costly and complex, and so 18 we have, you know, in the past cooperated with DOE and 19 various DOE labs, the Electric Power Research 20 Institute, international organizations, the SMILE 21 program to accomplish, you know, in multiples sort of 22 NRC dollars.
23 We do have coordination, you know, we have 24 periodic calls and meetings with domestically and 25
71 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com internationally to sort of share what's going on with 1
harvesting, what new opportunities may be coming up, 2
or it be a plant shutting down or different 3
organizations pursuing harvesting initiatives, they 4
may be looking for, you know, just to share information 5
or maybe looking for partners. We look for 6
opportunities where we can jump on things that we think 7
is a good use of, you know, of our limited resources.
8 Also I'll just mention here we have had 9
some workshops, helped co-lead a workshop in 2017, in 10 2020, and they're also expecting to have one coming 11 up later this year in conjunction with a SMILE meeting 12 so we try to keep connections with folks that are doing 13 this type of work outside the agency, and even outside 14 the country.
15 And then just a final wrap-up slide. Just 16 conclusions and key messages. Harvesting we think is 17 an important tool to help improve our understanding 18 of materials and component aging that can help inform, 19 you know, license renewal, subsequent license renewal, 20 aging management approaches, and our previous knowledge 21 of how materials age.
22 We are pursuing a proactive harvesting 23 strategy that includes maintaining and updating our 24 harvesting priorities, seeking harvesting 25
72 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com opportunities from domestic and international sources 1
that align with our opportunities, you know, and then 2
ultimately and pursuing specific harvesting 3
initiatives and subsequent research that results from 4
that.
5 We do try to maximize our collaboration 6
with other organizations, such as EPRI, DOE, and 7
international counterparts where it makes sense, and 8
then that helps us to get the maximum benefit for the 9
lowest cost to the U.S. taxpayer to achieve NRC 10 objectives.
11 I appreciate the opportunity to brief the 12 committee and certainly happy to field any questions.
13 MEMBER SUNSERI: Great, thank you.
14 Members, any other questions for the presenters?
15 VICE CHAIR KIRCHNER: This is probably not 16 a quick one. You said you had a model for just about 17 everything. Where's the feedback loop in all of this?
18 In RES you get data. Have you been able to measurably 19 improve your models, particularly with regard to age 20 and/or fluence?
21 MR. HISER: I think Rob made a comment 22 about having a model for everything so I'll let him 23 answer this.
24 VICE CHAIR KIRCHNER: Yeah, probably for 25
73 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com Rob.
1 MR. TREGONING: There's an answer for 2
everything too. Rob Tregoning, NRC staff. Again, 3
it's really dependent and it's really fluid, but yeah, 4
I mean, this is the ultimate validation, right? So 5
if you can't demonstrate your models using actual 6
materials then it causes you to reconsider those models.
7 VICE CHAIR KIRCHNER: Any highlights 8
though? You know, in particular that so far because 9
you've been doing this, you've been able to --
10 MR. TREGONING: Actually improve the 11 models? The one thing I haven't talked about that we 12 didn't talk a lot about was the baffle former bolt issue.
13 That's a little bit more mature.
14 There was some initial screening models 15 that were developed by industry and they didn't account 16 for all the different failure modes that they could 17 actually, those bolts would experience, so once they 18 started seeing some operating experience and then they 19 did -- they pulled bolts, they did root cause analyses.
20 They were able with that additional information to 21 go back and update their models, try to account for 22 these new failure mechanisms.
23 That's probably a good recent example where 24 information, not only operating experience, but 25
74 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com operating experience coupled with harvesting has been 1
used explicitly to refine and improve models. Matt 2
talked about our Zorita experience and we've got some 3
very interesting results.
4 We're at the point where we're trying to 5
understand how we do need to modify our models to 6
incorporate and account for these results, so sometimes 7
it's easy to do, sometimes it requires a little bit 8
more exploration. And at least for the Zorita models 9
we're in that a little more exploration stage to try 10 to understand how we need to tweak our models.
11 MR. HISER: And it depends on the models.
12 You know, the model is relevant to the Zorita 13 experience, but more empiricals, so now it's how are 14 we layering, how are we analyzing prior experimental 15 data to this new experimental data and, you know, and 16 weighing each of those?
17 You know, the baffle-former bolts, they 18 were clear just new phenomenon that really hadn't been 19 considered in the original models, so it's maybe not 20 easier but, you know, a greater, a different way of 21 updating the model.
22 MEMBER SUNSERI: Anything else?
23 (No audible response.)
24 MEMBER SUNSERI: All right, I guess I'll 25
75 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com open it up for any public comments. Anybody listening 1
in, if you have a statement you want to make go ahead 2
and make your statement. State your name and make 3
your statement.
4 (No audible response.)
5 MEMBER SUNSERI: All right, we have 6
another five seconds.
7 CHAIR REMPE: Only that five seconds? I 8
want to thank the staff and RES for being willing to 9
come and brief us. I think this helps us not only for 10 our eventual research report that we issued but also 11 just gives us more knowledge of what's going on. So 12 I appreciate it, and I appreciate Matt and Hossein 13 helping facilitate this, and I guess that's all I have 14 to say.
15 We are now going to go off the record for 16 the court reporter for this whole meeting, and we'll 17 come back at ten after to resume our letter on the fusion 18 SECY which has become very popular. Okay. Thank you 19 everybody.
20 (Whereupon, the above-entitled matter went 21 off the record at 2:55 p.m.)
22 23 24 25
Update on NRC Materials Harvesting Activities Matthew Hiser, Jeffrey Poehler, and Robert Tregoning NRC Office of Nuclear Regulatory Research October 6, 2022 ACRS Briefing
Outline
- Background
- Motivation and Strategy
- Harvesting Priorities
- Previously Harvested Materials
- Harvesting Opportunities
- Recent and Current Activities
- Metals, Concrete, Fire Research, Electrical
- Outreach and Partnerships
- Conclusions and Key Messages 2
Materials Harvesting Background
- Historically, NRC, industry and others have performed research on materials harvested from a broad range of components
- Current harvesting objectives focus on materials aging during long-term operation:
- Confirm results from laboratory experiments and analytical simulations to improve understanding of aging by testing materials aged in operating plants
- Reduce uncertainty in current state of knowledge of aging and NDE effectiveness to enable informed NRC review of aging management programs 3
Figure: Control rod drive mechanism (CRDM) Nozzle 63 from the North Anna Unit 2 reactor (NUREG/CR-7142)
Current Situation
- In the past, harvesting efforts have generally been reactive as limited new opportunities arose
- Few plants shutting down led to more demand than supply
- In recent years, a significant number of plants have shut down and entered the decommissioning process
- Generally operated for a long period, which provides more highly aged components for harvesting
- Currently more supply of harvesting opportunities than in the past
- Current situation calls for a more proactive strategic approach 4
A Strategic Approach to Harvesting
- In 2015, NRC began an effort to develop a materials harvesting strategy
- NRC previously was very reactive to harvesting opportunities
- Harvesting challenges
- Expensive, complex, and time-consuming (particularly with irradiated materials)
- Documentation of component fabrication and aging conditions
- Decommissioning vs. harvesting 5
- Strategy: Focus on high-value harvesting opportunities
- Seek cooperation when possible to maximize limited NRC resources
Proactive Harvesting Strategy 6
- 1. Identify and prioritize harvesting interests
- Focused on the unique value of harvesting relative to other sources of information (e.g. accelerated aging, operating experience)
- 2. Consider use of previously harvested materials when possible
- Greatly reduced cost, time and complexity compared to new harvesting
- Limited in the range of materials and aging conditions represented
- 3. Gather information on harvesting opportunities
- Requires sufficient information to meaningfully compare to priorities
- Challenging to acquire across the population of decommissioning plants
Technical Prioritization Criteria 7
Criticalness of Technical Issue Addressed
- Higher safety significance and less available data leads to higher ranking Importance of Harvested Materials over Laboratory Aging
- In-plant aging conditions or materials that are more difficult to replicate in the lab leads to higher ranking Applicability to US Operating Fleet
- Applicability to a greater number of plants leads to higher ranking Regulatory Considerations Related to Inspections and AMPs
- Greater availability and confidence in inspection methods or aging management approaches leads to lower ranking
High Priorities - Metals Interest Description Purpose / Testing Planned Technical Knowledge Gained Harvesting Status 600 thermally treated (TT) steam generator (SG) tubes with shallow flaws Non-destructive examination (NDE) and mechanical testing NDE assessment / detection and structural integrity for shallow flaws Seeking opportunities Thermally aged unirradiated cast stainless steel (CASS)
Fracture toughness and microstructure Fracture toughness data in real conditions to compare to accelerated aging data Identified and pursuing opportunity Bottom-mounted instrumentation (BMI) nozzles with known PWSCC indications Residual stress measurements and crack initiation/growth testing Confirm adequacy of current inspection requirements Seeking opportunities -
very few plants with known BMI indications Flaw characterization Confirm NDE effectiveness and flaw distribution Higher fluence stainless steel (SS) welds (>2 dpa)
Fracture toughness, IASCC CGR, and microstructure Properties to inform inspection scope and interval and flaw evaluation Addressed by SMILE*
and other opportunities 8
- SMILE = Studsvik Materials Integrity for Life Extension
High Priorities - Concrete/Structural and Electrical 9
Interest Description Purpose / Testing Planned Technical Knowledge Gained Harvesting Status Irradiated concrete
- In-situ and in-service data for model verification
- In-situ NDE
- Mechanical and microstructural properties characterization
- Benchmark structural damage
- Potential further irradiation
- Confirmatory testing and uncertainties reduction
- Evaluating rate effects (in-service conditions vs accelerated irradiation)
- size effects (real structure vs test specimen in test reactor)
- Evaluating concrete radiation and damage depth/gradients in concrete bioshield
- Inform structural integrity evaluation and inspection Identified and actively pursuing opportunity.
Reactor supports Embrittlement, fracture toughness, microstructure Structural integrity and performance. Inform inspection scope.
Identified and pursuing opportunity.
Electrical Cables (low and medium voltage)
Comparison of service aged specimen with accelerated-aged samples. Assess NDE effectiveness. Assess fire spread and thermal failure criteria.
Confirm technical basis for aging management programs.
Seeking opportunities.
Previously Harvested Materials
- NRC staff have catalogued previously harvested materials from prior NRC-sponsored research, including:
- PNNL - large array of components from penetrations up to large piping sections used for NDE research
- Battelle - large primary system piping and elbows
- ANL - smaller irradiated reactor internals materials
- Other sources of previously harvested materials:
- U.S. Department of Energy (DOE) Nuclear Fuels and Materials Library (NFML)
- Studsvik - SMILE-related and other harvested materials
- Halden Reactor Project 10
Harvesting Opportunities
- NRC has worked with EPRI to develop a harvesting opportunities table
- Covers domestic and international harvesting opportunities (decommissioning or announced shutdown date plants)
- Examples of column headings shown below:
11
Recent and Current Harvesting Activities Plant Components Harvested Status Bellefonte Electrical enclosures NUREG-2180; NUREG/CR-7197 Zion Neutron absorber materials ML19155A215 Electrical cables Testing ongoing Electrical bus ducts OECD/NEA/CSNI/R(2017)7 Crystal River 3 Electrical bus ducts Testing recently completed Zorita Reactor internals ML22132A039; ML20198M503 SONGS 2 Unirradiated concrete ML22119A092 Ringhals 2 RPV, internals, RPV penetrations, SG tubes, piping OECD/NEA SMILE ongoing through 2025 Oskarshamn RPV, internals, piping 12
Metals Harvesting
- Recent and current activities:
- Neutron absorber materials from Zion
- Reactor internals from Zorita
- Various metallic components through OECD/NEA Studsvik Materials Integrity for Life Extension (SMILE) Project
- Pursuing additional opportunities for more targeted harvesting from domestic and international plants
- Focused on high-value components in alignment with NRC priorities
- Working in cooperation and coordination with DOE and EPRI 13
SMILE Project Overview
- Harvesting, characterization and testing of metallic components from decommissioning Swedish BWR and PWR
- Reactor pressure vessel low alloy steel
- Stainless steel internals: core shroud / barrel welds, baffle plate, baffle bolts
- Nickel alloy penetrations, piping, and steam generator tubes
- Reactors:
- Ringhals 2: Westinghouse 3-loop PWR with ~ 30 EFPY
- Alloy 690 and Alloy 52 weld metal from the worlds second oldest replacement steam generator (1989) and oldest RPV head (1995)
- Oskarshamn 2: ABB-Atom BWR with ~30 EFPY
- Highly leveraged program for NRC with 8 countries participating along with EPRI 14
Concrete Harvesting
- Recent and current activities:
- Harvested unirradiated concrete from San Onofre Nuclear Generating Station (SONGS) 2 to evaluate its susceptibility to irradiation (RIL 2022-07)
- Based on mineralogy and irradiation level, irradiated concrete from SONGS would be a valuable opportunity to study irradiation-assisted concrete degradation
- Obtained from SCE available plant documents, reports, drawings and concrete specifications
- Drafted potential research plan
- Actively pursuing opportunity to harvest irradiated concrete to improve understanding of irradiation effects on concrete performance with harvest and research scope to include:
- Harvest irradiated concrete from biological shield structures
- In-situ testing and NDE
- Laboratory research (mechanical testing, microstructural characterization), benchmarking damage progression in bioshield against SONGS data, and potential further irradiation 15
SONGS Unirradiated Concrete Evaluation Al Ca Fe K
Mg Mn S
Si Ti Zn 3 slices were cut for petrography and µXRF
µXR FµXR F
µXR F
Aggregate extraction
- 3 unirradiated cores harvested from the steam generator enclosure.
- Large content of silicates in fine-grained aggregates
- Various characterization methods:
UPV, µXRF, petrography, XRD, SEM 16
Harvesting for Fire Research
- Recent and current activities:
- Electrical enclosures from Bellefonte to study fire detection and heat release rates in electrical enclosure fires
- Electrical bus ducts from Zion and Crystal River 3 to perform high-energy arc fault (HEAF) testing on representative samples
- Seeking opportunities to acquire and study aged electrical cables to determine if fire resistance is decreased after aging 17
High Energy Arcing Fault Experimental Series
- NRC is the operating agent under an OECD/NEA HEAF 2 Agreement.
- Agreement covers 21 tests sponsored jointly between the NRC and eight other member countries
- In 2022, 10 medium voltage tests were performed. Eight of those tests were medium-voltage non-segregated bus duct.
- Recent research (draft NUREG-2262) indicates that many bus duct scenarios have a damage region (zone of influence) larger than originally proposed in guidance (Supplement 1 to NUREG/CR-6850).
- These tests provide valuable data to evaluate the latest models to access the HEAF hazard in medium-voltage equipment.
18
Equipment Harvested for HEAF Testing
- Harvested materials: Two sections of 3-phase 5kV, 2,000 A, non-segregated bus ducts were acquired from Crystal River 3.
- All aluminum bus duct and bus bars; 3 conductors per phase.
19
- These ducts complement the six other ducts that were procured new.
- All 8 ducts were tested in a common manner and measured for thermal response.
- Test parameters were 4.16kV, 30kA, 2 or 4 seconds
- Preliminary results show models are reasonably predicting the hazard.
Before After 4 seconds
Harvesting for Cable Aging Research
- Recent and current activities:
- Currently performing loss-of-coolant accident (LOCA) tests on electrical cables (including some harvested cables from Zion) aged to simulate 50, 60, and 80 years of operation
- Seeking opportunities to engage with external stakeholders to identify harvesting opportunities that are representative of cables installed in U.S. plants
- Harvested materials will be helpful to validate whether NDE techniques can effectively track the degradation of electrical cables and cable accessories over their service life
- Future plans focus on addressing topics related to cable condition monitoring, aging management, and environmental qualification 20
Harvesting Outreach
- NRC held a public meeting* on Status of NRC Harvesting Activities in June 2022 to update the public on NRC harvesting activities and receive feedback from stakeholders.
- The meeting featured presentations by the NRC staff, DOE, EPRI, international organizations (Studsvik and Vattenfall) involved with harvesting, and Beyond Nuclear.
- One topic raised by public was to consider risk from external events and non-safety related components such as flood seals in developing harvesting priorities.
- As a result of this feedback, the staff is exploring opportunities to harvest flood seals from decommissioning plants 21
- Meeting summary and presentations are at ML22178A155.
Harvesting Partnerships
- Partnering and information sharing is essential to manage the costs and complexity associated with harvesting activities
- Past NRC cooperation on harvesting has involved:
- U.S. Department of Energy (DOE)
- Electric Power Research Institute (EPRI)
- International organizations
- Coordination achieved via periodic calls and meetings with domestic and international researchers 22
Conclusions and Key Messages
- Harvesting is an important tool for enhancing our understanding of materials and component aging
- NRC is pursuing a proactive harvesting strategy that includes:
- maintaining and updating harvesting priorities
- seeking harvesting opportunities from domestic and international sources that align with priorities
- NRC maximizes collaboration with other organizations such as EPRI and DOE to gain the maximum benefit for the lowest possible cost 23
Acronym List ANL Argonne National Laboratory B&W Babcock and Wilcox BWR Boiling water reactor CE Combustion Engineering CGR Crack growth rate DOE Department of Energy EPRI Electric Power Research Institute FT Fracture toughness IASCC Irradiation-assisted stress corrosion cracking INL Idaho National Laboratory XRF Micro X-ray fluorescence MWt Megawatt-thermal NDE Nondestructive examination NEA Nuclear Energy Agency OECD Organization for Economic Co-operation and Development PNNL Pacific Northwest National Laboratory PWR Pressurized water reactor PWSCC Primary water stress corrosion cracking RPV Reactor Pressure Vessel SCC Stress corrosion cracking SEM Scanning electron microscopy SMILE Studsvik Materials Integrity for Life Extension SONGS San Onofre Nuclear Generating Station SS Stainless steel TEM Transmission electron microscopy UPV Ultrasonic pulse velocity XRD X-ray diffraction 24
A sampling of harvesting related reports 25 1.
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.
2.
Kurtz, R. J., et al. 1990. Steam Generator Integrated Program/Stream Generator Group Project, Final Project Summary Report, NUREG/CR-5117, PNL-6226. Prepared for the U.S. Nuclear Regulatory Commission (NRC) by Pacific Northwest Laboratory, Richland, Washington.
3.
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.
4.
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.
5.
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.
6.
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.
7.
A.B. Johnson, Jr., S.K. Sundaram, F.A. Garner, Program Plan for Acquiring and Examining Naturally Aged Materials and Components for Nuclear Reactors, PNNL-13930, Pacific Northwest National Laboratory, December 2001. (Prepared for the U.S. Department of Energy).
8.
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.
9.
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.
A further sampling of harvesting related reports 26 10.
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.
11.
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.
12.
R. Fuentes, et al. Characterization and Analysis of Boral from the Zion Nuclear Power Plant Spent Fuel Pool, SRNL-TR-2018-00244, Rev. 0, Savannah River National Laboratory, March 2019 (ML19155A215).
13.
P. Ramuhalli, et al. Criteria and Planning Guidance to Ex-Plant Harvesting to Support Subsequent License Renewal, PNNL-27120, Rev. 1, Pacific Northwest National Laboratory, March 2019 (ML19081A006).
14.
Y. Chen, et al. Crack Growth Rate and Fracture Toughness Tests on Irradiated Ex-Plant Materials. ANL-19/45, Argonne National Laboratory, July 2020 (ML20198M503).
15.
Chen, Y., W-Y. Chen, and B. Alexandreanu, Irradiated Microstructure of Zorita Materials, ANL-20/50, Argonne National Laboratory, Lemont, IL, August 2020. (ML20269A143) 16.
Kombaiah, B., C. Judge, J. Charboneau, S. Smith, L. Gimenes Rodrigues Albuquerque, and V. Montes de Oca Carioni, Chemical Compositional Analysis and Microstructural Characterization of Harvested Zorita Reactor Pressure Vessel (RPV) Internals, INL/EXT-21-62220, Idaho National Laboratory, Idaho Falls, ID, March 2021. (ML21124A112) 17.
Le Pape., Y., et al, Assessment of San Onofre Concrete Susceptibility Against Irradiation Damage, Research Information Letter (RIL) 2022-07. Prepared for the U.S. Nuclear Regulatory Commission (NRC) by Oak Ridge National Laboratory, Oak Ridge, TN, 2022.
18.
Hiser, M., P. Purtscher, R.Tregoning, NRC Technical Assessment of Zorita Materials Testing Results, Research Information Letter (RIL) 2022-05. U.S. Nuclear Regulatory Commission (NRC), May 2022.