ML20236S545
| ML20236S545 | |
| Person / Time | |
|---|---|
| Issue date: | 07/21/1998 |
| From: | NRC COMMISSION (OCM) |
| To: | |
| References | |
| REF-10CFR9.7 NUDOCS 9807270016 | |
| Download: ML20236S545 (145) | |
Text
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UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION l
l
Title:
MEETING WITH ADVISORY COMMITTEE ON NUCLEAR WASTE (ACNW) --
PUBLIC MEETING Location:
Rockville, Maryland Date:
Tuesday, J.uly 21,1998 Pages:
1 - 65 Y
/
[W g72 g 980701 PT9.7 PDR a
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l DISCLAIMER This is an unofficial transcript of a meeting of the United States Nuclear Regulatory Commission held on July 21, 1998, in the Commission's office at One White Flint North, Rockville, Maryland.
The meeting was open to public attendance and observation.
This transcript has not been reviewed, corrected or edited, and it may contain inaccuracies.
The transcript is intended solely for general informational purposes.
As provided by 10 CFR 9.103, it is not part of the formal or informal record o'f decision of the-matters discussed.
Expressions of opinion in this transcript do not necessarily reflect final determination or beliefs.
No pleading or other paper may be filed with the Commission in any proceeding as the result of, or addressed to, any statement or argument contained herein, except as the Commission may authorize.
1 1.
UNITED STATES OF AMERICA 2
NUCLEAR REGULATORY COMMISSION 3
4 MEETING WITH 5
ADVISORY COMMITTEE ON NUCLEAR WASTE (ACNW) 6
.7 PUBLIC MEETING 8
9' Nuclear Regulatory Commission 10-Room 1F-16 11 One White Flint North j
i 12L 11555 Rockville Pike 13 Rockville, Maryland 14 15 Tuesday, July 21, 1998 16 17 The Commission met in open session, pursuant to 18 notice, at 1: 33 p.m.,
the Honorable SHIRLEY A. JACKSON, 19 Chairman, presiding.
20.
21 COMMISSIONERS PRESENT:
22
. SHIRLEY A. JACKSON,'
Chairman of the Commission 23 NILS J. DIAZ, Member of the Commission 24 EDWARD McGAFFIGAN, JR., Member of the Commission i.
25 l
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1 STAFF AND PRESENTERS SEATED AT COMMISSION TABLE:
2 B. JOHN GARRICK, Chairman, ACNW 3'
CHARLES FAIRHURST, Member, ACNW l,
4 GEORGE:HORNBERGER, Member, ACNW 5
R.G. WYMER, Member ACNW 6
JOHN LARKINS l
7
~ JOHN C. HOYLE, Secretary i.
8 KAREN D.
CYR,' General Counsel
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9 ANNETTE C. VIETTI-COOK, Assistant Secretary
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j; 10.
11 12 13 14.
15 16 17 18
. 19 20 l
. 21 22 23 24 25 L
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1 PROCEEDINGS 2
(1:33 p.m.]
3 CHAIRMAN JACKSON:
Good afternoon, ladies and 4
gentlemen.
Commissioner Diaz is running a little late and
)
5 he asked that we begin.
6 Today the Commission will be briefed by the l
7 Advisory Committee on' Nuclear Waste on several technical issues related to-the management and disposal of radioactive 8
9' waste.
The Commission looks to the ACNW, as it is called, 10
'to provide it with technical advice to ensure the safe 11 management and disposal of this country's radioactive waste.
12 The Commission was last briefed by the ACNW on i
13 December 18th of last year.
We seem to have a long time 14-period between these briefings.
15 Today's briefing will include discussions on four 16 topics that are of great interest to the Commission.
These 17 include, first, the ACNW's views on risk-informed,
- 18 performance-based regulation.
Second, the interim guidance 19 in support of the final rule on radiological criteria for
- 20 license termination.
Third, the NRC's waste-related 21-research program.
And, fourth, the near-field environment 22
'and performance of engineered barriers in a high-level waste 23 geologic repository.
24 In addition to these discussions, the ACNW will 25 also address its plans, priorities and accomplishments for ANN RILEY & ASSOCIATES, LTD.
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fiscal year 1998 and its plans and priorities for fiscal 2
year 1999.
The Commission looks forward to interacting with 3
-you on all.of these topics.
,4 And unless my colleague has any comments, please 5'
begin, Dr. Garrick.
6 DR. GARRICK:
Thank you.
I agree with you it has 7
been a little bit.too long since we have had a chance to 8
meet, and I.think the resources in here are adequate to do 9
something about that, so we will try to do that.
10 We are going to first talk to you, as you 11 indicated, about the positions of the Advisory Committee on 12 risk-informed, performance-based regulation, and we have 13 been pretty direct and outspoken on those positions in a 14 number of letters.
15 CHAIRMAN JACKSON: -Good.
E16 DR. GARRICK:
And what I want to do is just kind 17' of reiterate our views on some of the key points having to 18 do with this approach.
So in my first exhibit, I point out 19 that we as a Committee strongly support whatever we can do 20 to enhance the language of this discipline, and important to 21 that is moving towards a common terminology.
And w'e have 22 been very encouraged by the Commission's view on wanting to 23 do that as well.
So I think that will help the process a 24 lot.
25 We have also expressed our position several times ANN RILEY & ASSOCIATES, LTD.
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1 that we believe that as we move towards a risk-informed, 2
performance-based method of operation, that it will give us 3
a basis for making our regulations more efficient and moving 4
in the direction of some forra of-optimization of the
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5 regulations.
6 As we have said on a number of occasions,'and as 7-you have also'said, it is very important that if the agency 8-is going to move in this direction, that we do it in such a i
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9-way that the language applies to everything essentially-that l
10 the agency does.
So even though this activity had its birth in and has emerged primarily from the reactor business, the 11
-underlying principles are sufficiently basic that they can 12 13 apply to, we believe at least, all of the activities of the i
14
. agency.
15 CHAIRMAN JACKSON:
Please.
16 DR. GARRICK:
Yes.
'17 COMMISSIONER McGAFFIGAN:
Dr. Garrick, we had a 18 stake. holders meeting last week, and I don't know -- I saw i
19 some ACRS members there.
I am not sure whether you all were 1
20 there._
But we asked about risk-informing Part 50, and I
' think the answer that we got was that there are some --
22 let's finish what we are doing now, get these various Reg.
'23 Guides out and working.
Dr. Remick said there may be an 24 opportunity in Appendix B to strip some stuff out that the
~
25-maintenance rule may be now adequately dealing with.
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.But there wasn't a lot of enthusiasm for a 2
comprehensive rewrite.
And it strikes me that what I am 3
learning, and you said earlier that it came out of the 4-reactor side, but in some sense, the waste side has gotten 5
ahead of that reactor side because it is a new area.
6-DR. GARRICK:
Yes.
i 7
COMMISSIONER McGAFFIGAN:
It is easier to bring 8
this new framework ~into an area where you are starting from 9
scratch than it is where you have a large body of work 10 a'. ready there and the stability of the regulatory framework, 11 however deterministic and prescriptive, and whatever it may 12 be.
Better the devil you know than the devil you don't 13 tends to become a counter-wait.
14 Do you have any thoughts about that?
As I say, 15 you'll have to take my word that that was the general 16~
consensus of some of the industry folks.
And you might not 17 have concurred in it if you had been present, but whatever.
18 DR. GARRICK:
Well, I think that you are ccrrect 19 in that the waste field has some advantage, particularly on 20 the' performance side, because the standards are basically 21 performance-based, and the primary activity hab been in the 22 high-level waste arena and that is where most of the 23 attention has been given with respect to establishing a 24 performance-based standard.
So I think there is an 25 advantage.
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On the probabilistic side, I think that the waste 2
side has had some catching up to do, and I believe they have 3
done a very good job of that.
And I think they have been 4
sometimes frustrated by not being able to capture as much of 5
the methods that come out of the reactor business and 6
transfer those to the waste business, as some would like.
7 But, certainly,.some of the fundamental principles, they 8
have been able to do that.
1 9
As far as the question of how fast we should move, 10 I think that it is very difficult when you have got a system 11 that seems to be working, that people are well-skilled in, 12 trained.
It is difficult to talk about change, and I think 13 there will be a natural resistance to that.
On the other 14 hand, you would certainly expect that from me.
15 I think the change is justified.
The benefits for 16 doing so are there.
I think we are in a time of metrics and 17 measurements.
I think the risk-based process gives us a 18 much better basis for measuring our performance and being 19 focused in terms of having reasonable confidence that we are 20 dealing with the right priorities.
So I expect that.
I 21 expect there will be a resistance and people saying that i
22 maybe we shouldn't go make substantial change.
l 23 And I think we have to be.very selective where we 24 make the change and what-have-you.
And I would hope that 25 one of the areas where there would be rather quick change l
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-would be in the analysis activities that are ongoing.
There 2
is no reason that all of our analysis activities shouldn't 3
be risk-informed right now, regardless of the regulations.
4 I would like to think that a comprehensive, risk-oriented 5
analysis contains within it all that is required for the 6
existing regulations.
7 But,I hope, as you will see in a moment, that we 8
move in a direction where maybe some of the existing 9
regulations can either be simplified or'even eliminated.
10 CHAIRMAN JACKSON:
So let me make sure I 11
' understand your point.
There are really two.
One is that 12 you-believe that even within the existing framework, that 13 essentially all of the analysis can be made risk-informed.
14 DR. GARRICK:
Yes.
15 CHAIRMAN JACKSON:
And that the second point you 16.
make is that there are some selected regulations that should 17 be or could be made risk-informed.
18 DR. GARRICK:
Yes.
19 CHAIRMAN JACKSON:
Even if we don't do a 20 comprehensive rewrite of Part 50, 21 DR. GARRICK:
Right.
22 CHAIRMAN JACKSON:
Could you speak to where you 23 think some of the opportunities are?
-24 DR. GARRICK:
Well, certainly, we heard a lot on 25 that reactor-side about Part 50 and about trying to embrace ANN RILEY & ASSOCIATES, LTD.
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9 the safety goals more directly into the regulatory process.
1 2
There has been lots of talk and discussion, and even work l
3 towards elevation of the core damage frequency as a l
l 4
surrogate of risk, and all of that is related in one way or 5'
another to Part 50.
6 In the waste side, I think the differences that 7
are probably going to manifest themselves between the 8
existing Part 60, for example, and what we expect in the new i
9 regulation, Part 63.
Some of those are clearly going to be
_10 driven by risk-informed interests and performance-based.
11 I think the idea of moving away from the 12 allocation of performance requirements to subsystem levels 13 is another direct indicator-that we are moving in the 14 direction of a more performance-based and risk-informed 15 approach.
So I think we are beginning to see things happen 16 and those are a couple of the regulations that I think would 17 be most -- most directly impacted.
i 18 CHAIRMAN JACKSON:
You also speak to the fact that 19 you feel that the concepts need to be sufficiently general 20 to accommodate all NRC activities.
Do you feel that, and I 21 know you have had some interaction at an earlier 22 incarnation, but do you believe that the concepts and
-23 definitions embodied in now the staff white paper on the 24 risk-informed, do you think they are general enough to 25-accommodate those?
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DR. GARRICK:
I think -- yes, I think that is very 1
2 much in the right direction.
The version that I have seen, 3
I am very encouraged.
I think it. clearly has a stronger 4
orientation to risk than -- and performance than any similar 5
paper that I have seen.
6 CHAIRMAN JACKSON:
And the last question, we did 7
have a Commission meeting a couple of weeks ago on PRA and 8
the propagation of it into materials-related areas in 9
particular, waste management areas.
Do you agree that -- or 10 do you believe that the staff has a comprehensive plan or a 11 comprehensive framework for using risk-informed approaches 12 to optimize our regulations and regulatory approaches, 13 including analyses, in these areas?
14 DR. GARRICK:
Well, being sometimes accused of 15 being a zealot in this discipline, obviously, I am never 16 satisfied.
And I think that, you know, there is a desire 17 always to see progress and more progress.
But I have 18 followed what has been going on, and both facilities, the 19 nuclear waste facility side and then the reactor side, and 20 have been very encouraged that -- with most of what is being 21 done.
22 I have also been encouraged by the fact that, for 23 example, the ACRS has capability in this arena that they 24 haven't had in the past, and I think that is very, very 25 helpful.
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11 1.
So I think there is a lot of work to be done, but I see some of the' fundamental building blocks being put in 2
l 3
place, and the white' paper is clearly one of those.
4 COMMISSIONER McGAFFIGAN:
One of the points you i
made a few minutes ago was that you think there could be a 5
L 6
quick change in the ongoing analysis activities of'the 7
agency regardless of the regs.
We are dealing with one at 8
the moment, 50.59, where if you have any ideas as to how to 9_
make that quick change, they would be welcome, because we 10 are having a heck of a time.
We have this design, basis 11-
. analysis that is the fundamental --
12 DR. GARRICK:
Right.
13
, COMMISSIONER McGAFFIGAN:
sort of stylized 14 analysis that underlies that and the whole -- the whole of 15 Part 50, really.
And the Commission, sort of naively, in 16_
its SRM said, well, you might be able to look at some of the
.17 work you did on Reg. Guide 1.174 and try to define --
'18 CHAIRMAN JACKSON:
Right.
Go forth and do good.
.19 COMMISSIONER McGAFFIGAN:
Define minimal and sort 20 of the same sort of notion you just threw out, and we are 21
~ not there yet.
)
22 DR. GARRICK:
Yes.
I 23 COMMISSIONER McGAFFIGAN:
Dr. Aposotolakis in the 9
24 ACRS has thrown something across the transom that may help, 25 but we are struggling with how you build in, even in our 1
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analysis, a-risk-informed analysis to deterministic 2.-
prescriptive regulations.
I 3
DR. GARRICK:
Yes.
4 COMMISSIONER McGAFFIGAN:
And the design basis 5'.
accident analysis.
,6 DR. GARRICK:
Well, I have to live my colleagues 7~
here, and for me to really get into 5059, --
8 COMMISSIONER McGAFFIGAN:
I know.
9 DR. GARRICK:
-- I might spend the rest of the 10 day.
But I think -- I am a great believer in the top-down 11 approach.
I think if we come to grips with some 12 fundamentals and some policy issues, and some methods, and 13 the' staff begins to embrace those and get trained in them, 14 that, you know, we will see solutions that we didn't see 15 before.
16 Now, I will comment on a couple of things that you 17 mentioned as'I go along here.
Fortunately, the questions 18 you have asked has allowed me to cover most of what I have
~
19 just' covered.
So I think we are in pretty good shape.
. 20' So let-me return to-the exhibit on risk and risk 21 assessment.
I am a great believer that in any science if 22!
the science is to move' forward, you have to have some way of 23
-measuring and risk is no.different than that, and'the more 24 ~
the measurements can be in terms of fundamental principles, 25
- first principles, the more broadly it will apply to systems ANN-'RILEY & ASSOCIATES, LTD.
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that we have to worry about, so I think the encouragement
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here is to not get locked into a single measurement 3
necessarily that constitutes what we mean by risk, because 4
it usually does not quite do the job.
4 5
One fundamental that we have seen work very well in the applications arena is something we call the triplet 6
7 definition of risk.
Whether we have been analyzing the risk 8
of importing agricultural animals and the implications that i
9 has on disease rate or whether we are analyzing the space 10 shuttle or a chemical refinery or a nuclear power plant, the triplet definition of risk has applied and been a very 11 12 constructive framework within which to ask the important I
13 det ailed questions -- what can go wrong, how likely, what 14 are the consequences approach in practice has seemed to work 15 very well.
16 Given that that is kind of what one might assume t
17 is a definition of risk, I also like to look upon it as 18 containing the definition of deterministic safety analysis.
19 Even in the old days when we were doing safety analysis of 20 nuclear power plants, long before PRA, we used to ask the 21 doublet question -- what can go wrong and what are the 22 consequences? -- so in the context of the triplet, what we 23 like to say is it's not a question of deterministic versus 24 probabilistic.
It is a question of whether or not you want 25 to deal with the question of uncertainty and likelihood of a ANN RILEY & ASSOCIATES, LTD.
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._ safety, analysis and.if you do a safety analysis becomss a
.ris'k[ analysis -- so.that is an example of a general kind-of.
'2?
3' fundamental notion.
L
.4
' CHAIRMAN JACKSON:
Go' ahead.
5 COMMISSIONER McGAFFIGAN:
Before you-leave the
'6-slide,jthe triplet definition of. risk, if-we adopt -- I~
i f7
> remember being taught risk is probability. times consequences F
8
'for an individual event.-
It's.the sametthing --_what can go 491 wrong --
' 10 -
DR. GARRICK:.Yes.
11
. COMMISSIONER McGAFFIGAN:: But how important is itL 112!
that we develop-a common definition-across agencies, health-13i ag;encies,FDA, FAA~, EPA, et cetera cso thats we are 'not -
14~
~ speaking past each other?
- 15 LThere is_this report I think Gil Olman put outfa 16 _-
[ year;or two ago -,
17~
DR..GARRICK:
Yes.
.18 COMMISSIONER.McGAFFIGAN:
- >about risk and I l19.~
think;it_ talked 1about some of-this stuff, but.we.are'-' are J20; y'oulsuggesting we'just go ahead.or do we-try to foster a-
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'211
'commontlanguage or how do we_do what we'do inothe context of y
f 22-
. hatLeverything else is doing?.
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DR. GARRICK:
I don't know that_I would. sus 3est 024" Lthatfweiforce anything.
Icthink that-it'is a concept.that 325=
-has worked 1welli.and, generally concepts that work well are ANN RILEY;& ASSOCIATES, LTD.
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adopted and spread and become standards.
2 I have never been to one to think that there was L
3:
so much wisdom as to be able to know what the ultimate 4
definition ought to be, so I would think that if the agency 5
has lots of success with this way of thinking, this kind of
)
i' 6
definition, that it would be adopted by others.
7 As a matter of fact, the definition I am finding 8
is finding its way into a number of other arenas, including 9
defense and NATO -- I have seen it in NATO documents --
10 chemical and so.forth, so I think that there is enough 11 evidence out there that the idea has enough confidence 12 behind it or it wouldn't be suggested, that its acceptance 13 is not taking anybody out on a limb very far, but my 14 preference would be that the language would be standardized.
15 At least we would move in that direction.
)
' 16 COMMISSIONER DIAZ:
Yes.
Besides the def aition 17 of risk, of the triplet, in your set of fundamental 18 principles is there anything else you could put on the table 19 that would be more specific what you mean by fundamental set 20 of principles?
21 DR. GARRICK:
Yes -- well --
22 COMMISSIONER DIAZ:
Measures needed to be 23 interpreted in terms of --
24 DR. GARRICK:
Well, yes.
One thing that I'd put
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l 25 out on the table in the risk business is that I am very much j
t.
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1 a believer in evidence-based risk assessment.
I think that l
2 what we want to do is to have our risk assessments be 3
impersonal, not be dependent upon opinions and politics, 1
4 religion, or anything except the supporting evidence, so I j
5 think the evidence has to speak for itself.
6 I think that in order to do that you can very 7
often e;nence that process by the tools you select to 8
process that evidence,.and they need to be transparent and l
9 that not only means transparent with respect to the specific 10 exercises that you go through, but transparent with respect 11 to the logic that you employ.
12 You know, this is the. thing that sets risk 13-assessment apart from a lot of the other analyses that have 14 risk principles in them, and that is that usually in the 15 risk field we are trying to calculate something about which 16 we have very little or no information, and so what we have l
17 to do is map that requirement, that' number or that outcome 18 that we want down to where we have some information, and it 19 is that mapping that needs to be visible and if the logic is 20 visible and the information is clear, then of course you 21 move in the direction of transparency.
22 CHAIRMAN JACKSON:.Let me ask you two questions.
23 I mean I think I understand what you are trying to say.
24 One theoretically could say that superficially 25 there seems to be an inconsistency between, say, using PRA ANN RILEY & ASSOCIATES, LTD.
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to complement our traditional deterministic approaches, 2
which is what we talk about sometimes, and secondly, using 3
what you say is treating deterministic approaches or 4
analyses as a subset of risk analysis --
5 DR. GARRTCK:
Right.
6 CHAIRMAN JACKSON:
-- and it seems that the 7
resolution of that apparent inconsistency is in your triplet
'8 definition, namely that you are basically arguing that a t
9 deterministic analysis or approach answers the first and the l
10 third question and that PRA answers or attempts to answer 11 all three.
12 DR. GARRICK:
Right' 13 CHAIRMAN JACKSON:
So it is in that sense that the
{
14 deterministic analysis is the subset I
15 DR. GARRICK:
Yes
'16 CHAIRMAN JACKSON:
-- but it's also in that sense 17 that PRA is the complement that allows you to add in an 18 answer to the third --
19 DR. GARRICK:
Right 20-CHAIRMAN JACKSON:
-- to the second question, is i
21 that right?
22 DR. GARRICK:
Yes.
That's right.
23 CHAIRMAN JACKSON:
Okay.
Then the second question 24 I wanted to ask you is you spoke about evidence-based risk 25 assessment and of course one could raise the question of'the ANN RILEY & ASSOCIATES, LTD.
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.'1 use'of expert panels.~and expert judgment,.and is the point
<2 ?
you'are making that.this mapping needing to be made visible
- 3 and therefore the transparency of the logic, as you call
.4 it 5
DR. GARRICK:
Right.
6'
- CHAIRMAN JACKSON:
-- is that the way that one 7
justifies'and makes the-best use of expert judgment?
8 DR..GARRICK: _That's part of it, and you will 9:
notice I did not use the' word " data" because data conjures 10
'up'certain specific things.in~ people's minds, and: data is a 11'.
piece of evidence, but it is not the totiality-of evidence.
~12 The laws of physics are evidence,' logic'~is-13 evidence and expertLelicitation outcome is evidence --
'14 CHAIRMAN. JACKSON:
Okay.
215
.DR. GARRICK:
so-I think that'is what I was
-16 referring.'to.
17 CHAIRMAN JACKSON:
Okay.
18-
.DR..GARRICK:
All right.
.Let's go to risk 19.
assessment and defense-in-depth.
20 We have written to you much about those topics.
21 One of the' things that we see as an advantage of a 22L
' risk-informed approach is the opportunity-to add clarity to-23-the.' concept of) defense-in-depth,'the opportunity to move ~inL
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24;
.the direction of quantifying the contribution to' performance 25
- of'all. lines of defense.
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Of course, when we talk about quantification we 2
are really not talking about necessarily a property of the 3
real world 'o much as we are about the knowledge of the s
individual or individuals and their ability to express that 4
l-5 knowladge, and in order to express knowledge about rare 6
events you have got to have a mechanism and a form to do that that captures the fact that there's lots of things you 7
8 don't know or the fact that there are uncertainties, so 9
quantification doesn't necessarily mean a number.
It means 10 capturing the information in a form that conveys what you do 11 know as well as what you don't know, and some of the' lines
.12 of defense.you are going to know a lot less than others, and 13 if you have a way of communicating that, then you have a 14 real heads-up on the notion of defense-in-depth.
15 On risk-informed, performance-based terms, the
- 16 committee is very much in agreement with the positions we 17 have seen articulated by the Commission on the fact that a 18-risk analysis is not necessarily decision analysis.
Many 19 more things often go into a decision.
20 In risk there is always the opportunity to define
- 21 your risk parameters in such a way that they embrace issues 22 of cost and issues of schedule.
That kind of activity has 23 carried with it a whole new field called performance risk 24 analysis or programmatic risk analysis, but one has to be 25 very careful about using risk in decision-making and making i
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sure that it is in its proper context.
2 Performance-based -- there are major differences 3
between materials and reactor licenses in the case of 4
performance-based regulations.
I think we spoke to that at 5
the opening, that there's things that have been established 6
by tradition through the reactor field that have to be dealt 7
with in probably an evolutionary manner to move to the 8
risk-based way of thinking.
9 I think one of the primary compromises, if you 10 wish, of the doublet view of safety analysis is tPat 11 interpretation of design basis.
I think if we had not come 12 up with the concept of a design basis accident, I think the 13 coupling between safety analysis and risk analysis would 14
.have been much ersier to see.
15 Regulatory burden -- I think that most people who 16 are mature about this discipline and practice it look to 17 relief in regulatory burden.
They certainly don't look to a 18 relief understanding what the safety is, on the contrary 19 convinced that there will be much more knowledge about the 20 safety, but that eventually there needs to be some 21 efficiencies as a direct result of risk-informed practices 22 and those efficiencies need to take the form of changes in 23 the regulations.
24 So as to my closing comments, I think that we have 25 indicated a number of times that we think the risk view is ANN RILEY & ASSOCIATES, LTD.
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essential to judge the overall safety'of a repository.
It
-2 provides us the perspective we need.
j 3
.I think one of the things that is sometimes 4
underestimated is the experience base in the waste field.
5 While the use of probabilistic methods in the waste field 6
has come relatively late, the amount of activity has been 7
intense and the expenditure of effort, resources in the last 8
10 years, primarily through two projects -- the Waste
-9 Isolation Pilot Plan and the Yucca Mountain, proposed Yucca 10 Mountain repository.
11 As a result of those activities we have learned an 12 enormous amount about how to apply these methods to a 13 geologic system, and as we said, one of the things that is
~14 very important in evolving and transitioning to a risk way 15 of thinking is to not prescribe yourselves out of the 16 business.
We need to retain a certain amount of 17 flexibility, i
18 As to the details, even though we have been 19 arguing in my whole discussion here about the importance of 20 fixing some principles and the way we do some of the 21 analyses and the details,of some of the methods -- that 22 aspect of it needs to be flexible.
23 I think that's all I want to say about the subject
{
24 and I am certain available for questions.
25 CHAIRMAN JACKSON:
Okay.
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COMMISSIONER McGAFFIGAN:
I am not sure you ever 2
answered the Chairman's question about where the low-lying 3
fruit are in reactor space, but maybe your answer was that 4
your colleagues would get mad if you took all afternoon on 5-the subject, so --
6 DR. GARRICK:
I think one of the areas is to --
7
- okay, I' will answer that.
8 I think the design basis accident philosophy 9 ~
approach to regulation is sometimes a barrier to the 10 introduction of a risk-informed approach, and I think that 11 is a specAfic that you started to look at the regulations in 12 the_ context of design basis that you would maybe appreciate 113 that this is the one activity, this is the one analysis, 14 effort that has compromised, if you wish, an otherwise 15 doublet approach to safety analysis, and I know why it came 16 about and how it came about and that it was useful but it 17 created partitions that were artificial.
18 We got into class 9 accidents, severe accidents 19 and what have you, and these sort of artificial interfaces 20 that don't really exist-in nature.
And that we started 21 regulating against a design basis accident as if we did that i
22 we would never have a severe accident.
And we of course 23 learned that that's just not the case.
So that's one major i
24 issue that I would love to work with you on.
25 CHAIRMAN JACKSON:
Well, would you -- we'll give 4
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1 your colleagues plenty of time.
Would you care to speak to 2
50.59?
3 DR. GARRICK:
Well, I think that what you're trying to do, namely it's like somebody has said if somebody 4
5 comes in'for a change, even though we are not under a 6
. risk-based regulatory process right now, such changes cannot 7
be realized anymore without some level of a risk analysis.
8 And I would like to see the 50.59 accivities move more 9
aggressively in that direction to where there was increased
)
10 dependence on that, and'I think also there would be great 11 signals sent out to the licensees if with that came a real 12 examination of 50.59 in terms of its deterministic, in terms 13 of its traditional requirements.
14 I think that one of the things that is causing 15 quite a bit of anxiety, and I'm sorry I wasn't to the I
16 meeting last week, is that many people are discouraged about l
l 17 risk on a couple of counts.
One is this'whole idea of l
18 keeping a comprehensive risk assessment current is viewed as 1
19 an extensive burden,.and, two, and this involves the NRC,
-20 it's not clear to a lot of licensees just what the benefit 21 is, that if they have to go ahead and comply with all of the 1
22 so-called deterministic requirements, they're not so sure, 23 given the maturity of the industry, that they want to engage 24 themselves in a research-oriented kind of activity just for 1
25 the sake of building confidence in a risk-based approach to I
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24 1-regulatory practice.
2 So my view on this is that probably the. pilot 3
programs you have are.useful.
They provide a lot of 4
insights and. problems learning about the application of risk 5
to a whole. family of issues, everything from hydrogen 6
. recombiners and their necessity to the utility of a graded 7
quality assurance program.
But I think that the thing that 8
would really advance the cause would be some rather 9
significant backoff, if you wish, or modification if you 10 wish of a regulation that is a heavy burden, on the basis 11 that.you're now confident that what was being sought as a 12 result of that regulation is more than offset by the new 13 methods and the new practices.
14.
CHAIRMAN JACKSON:
Okay.
Thank you.
-15 Dr.'Fairhurst.
16 DR. FAIRHURST:
Thank you very much.
17 What I'm going to. address is-clearly a restatement
-18 of material communicated in a letter in April.
That was 19 based on a presentation in March from the Office of Nuclear 20~
-Regulatory Research concerning interim guidance and the 21' support of the final rule on radiological criteria for 22 license determination -- license termination, sorry.
23 I first lay out the several general observations.
24-
.One, that obviously decommissioning is a subject that's 25 going to be of continuing and probably growing regulatory ANN RILEY & ASSOCIATES, LTD.
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25 t
1 importance.
Secondly, that the license termination issue is l
2 a complex one, varies very widely from case to case from 3
very simple determinations to really quite complex 4
situations.
And the NRC resources required to deal with it
-5 are correspondingly quite varied.
6 Then the next observation was really a picking up a little bit on what Dr. Garrick's constant philosophy is 7
8 that we need to be dealing with a risk-infortaed,
'9 performance-based criterion.
This is another case'where the 10 changes that are envisaged are along those lines.
That's 11 not saying there is some need for -- there is a need for 12 regulatory consistency with respect to the use of the total 13 dose standard basing things on health effects, having some 14 flexibility in the regulatory approach because of this 15 complexity, and also in this particular case recognizing the 16 role of Agreement States.
They, too, feel they have a stake 17 in it.
18 An' issue that was brought to us and which I know 19 you're very familiar with, but it was raised first by the 20 industry, nuclear energy-industry, was this question of dual 21-Federal regulation, and that this is a serious problem and j
22 one that is not. easy to deal with, but somehow is going to 23 have.to be dealt with.
24 The main recommendations in our letter, first we 25 were somewhat. overawed by the complexity of the regulatory i
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guidance.
I think the word we.used was it was formidable.
2
'I think you responded in kind and said yes indeed you 3
understood it and that maybe it needs to be -- need to take 4
some advantage in this electronic age of finding ways to 5
make it'more comprehensible, user-friendly, and a little 6
more menu-driven format.
7 Another issue that we felt we needed to bring out 8
was that the ALARA approach maybe should be considered to be 9
in some cases leading to unnecessary conservatism, and we 10 feel that if'you could meet the 25 millirem all-sources or 11 pathways limit,- that should be sufficient.
I think in your 12 answer to us you mentioned a. concern or a feeling that in 13 some cases if it was a simple' thing to do, then one could 14 perhaps go lower if it was a question of just wiping things
-15 down.
But I think we still hold to the notion that that 25 16 millirem should be for most cases sufficient to meet what 17-we'd call ALARA.
18-COMMISSIONER DIAZ:
Could you please elaborate cn1 19 the reason why you believe that it's possible or it's 20 justifiable?
21-DR. FAIRHURST:
Well, yes.
In the -- first of 22 all, the doses that one receive from 25 millirem from all i
23 pathways I think generally would be considered to be of 24 little concern as far as health effects.
25 COMMISSIONER DIAZ:
Yes.
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1 DR. FAIRHURST:
There is also I think the feeling that the formula rem standard ground water but if you use 2.
)
3 the 25 millirem all pathways, it probably will in many cases 4
satisfy the formula rem.
I'm not an authority in this, but 5
it's what I've been led to understand, that if you look at 6
the requirements that are being suggested by people that j
7 this is not a major deviation from those in most cases.
8 COMMISSIONER DIAZ:
But it's the ALARA interface,
-9 what I'm concerned, we always put the ALARA interfaces and 10 the. additional satisfaction of --
11 DR. FAIRHURST:
Well, yes, you know, ALARA, as low 12 as reasonably achievable, and one can then argue, Dr.
13 Garrick wants evidence, wants facts, reasonable is a very 14 subjective word, and the question is what is reasonable.
15 And you can force somebody out of business perhaps-j 16 financially by pushing them to an enormous amount of effort 17 for very little benefit.
18 COMMISSIONER DIAZ:
We have a long history of
- 19 using ALARA.
20 DR, FAIRHURST:
Pardon?
21 COMMISSIONER DIAZ:
We have a long history of I
22 using ALARA.
.23 DR. RAIRHURST:
Oh, yes.
Yes, I'm just saying 24 that l
25 COMMISSIONER DIAZ:
We've managed to keep it f
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within bounds.
2 DR. FAIRKURST:
Right.
3 CHAIRMAN JACKSON:
Well, I mean, isn't also if I 4
go back to what Dr. Garrick was saying, that if you talk 5
about using risk analysis or, you know, today, particularly 6
within the ALARA framework, does that not offer a way not to 7
abandon what has been a cornerstone of how we've done our 8
business, but at the same time address the issue of s
9 unnecessary conservatism from a cost-benefit point of view?
10 DR. GARRICK:
Yes, and one thing that's very 11 important, and I'm sure that Charloo was going to comment on 12 this, is that when we say in reference to this specific 13 issue that the 25 rem is acceptable, that's not saying that 14 we don't believe in ALARA.
ALARA is a rational way to look 15 at things.
16 CHAIRMAN JACKSON:
That was my point.
17 DR. GARRICK:
If you can meet a standard and 18 spending 10 cents reduce it by 10, of course you would do 19 that.
20 CHAIRMAN JACKSON:
Right.
That's all.
21 DR. GARRICK:
Yes.
22 COMMISSIONER McGAFFIGAN:
This is a more generic 23 question, but I will point out you were listened to by the 24 Commission.
Our staff requirements memorandum on this 25 particular point uses the word "may."
It isn't quite as ANN RILEY & ASSOCIATES, LTD.
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definitive as definitive as you, but in addition if the licensee complies'with the 25 millirem dose criterion using 2
'3 the screening methodology, the D and D code which itself is 4
quite conservative, the licensee may have met the intended 5
ALARA requirement.
May have met.
We didn't, you know --
6 DR. GARRICK:
Yes.
7 COMMISSIONER McGAFFIGAN:
Therefore additional 8
demonstration of compliance may not be necessary.
So we did listen, but we also wanted to take into account by using 9
.10 those mays the circumstances where for 10 cents you get a 11~
factor of 10 --
12 DR.~GARRICK:
Yes.
Absolutely.
Absolutely.
13 CHAIRMAN JACKSON:
Okay.
14-DR. FAIRHURST:
And the final point that was made 15 in the letter was that we felt that the D and D' code that is being considered should have some flexibility for change if
-]US 17 one finds, for example, that the foundations on which it's 18 built change, such as the linear no-threshhold hypothesis.
19 And your response'I think was that if that is changed, it
'20 will have other ramifications apart from just modifying the 21 D and D code, and we know it will.
22 We also recommended that it would be useful to try 23 to take some' test sites, complex test sites, and go through 24 the implementing guidance and see how it works out in 25 reality.
There was a suggestion made that there might be
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1 some level of. conservatism by using generic parameters and 2
it might be possible and simple to locally add regional n
3 parameters, it might reduce the conservatism.
4 I might add in conclusion that yesterday we heard 5
a presentation from the NRC staff about developing a 6
standard review plan, and it appears that things are moving 7,
quite well along where they are about to test it on a 8
complex site'and they are considering a number of things to 9
improve flexibility.
So I think this-is on course.
10 CHAIRMAN JACKSON:
Yes.
Thank you.
11 COMMISSIONER McGAFFIGAN:
Did they give you a copy 12 of our SRM too'at some point, because a lot of that was 13 directed so that -- just so you know that your advice is 14 listened to, a lot of the thoughts in the SRM I think and I
15 part of all of us was the result of your work and very much 16 appreciated.
17 DR. GARRICK:
We are encouraged.
18 DR. FAIRHURST:
So we will give you an update 19 later, I think, not just back-patting but we did very much 20 appreciate your response-and comments to us on that.
It was
]
2 11 helpful.
It tells us that there is somebody listening and 22 responding.
Thank you.
'23 CHAIRMAN JACKSON:
Of course.
Somebody up here 24' even likes you.
25
[ Laughter. ]
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1-CHAIRMAN JACKSON:
That always helps.
l 2
Dr. Hornberger.
3-DR. HORNBERGER:
Thank you, Chairman Jackson.
As 4
always, it is a pleasure to be here.
5 My task today is to report to you on some of the 6
. work that the ACNW did in looking at the waste-related 7
research program within NRC.
And this was, as you know, 8
ACRS was asked to review 9
safety-related research and they asked ACNW to look at the I
10 waste-related portion.
11-The Office of Research has a fairly modest l
12-program, mainly in decommissioning and decontamination, and 13 the ACNW did hear presentations from staff of the Office of I
'14 Research on that.
15 The NMSS, of course, classifies their work as 16
-technical _ assistance, the work they do with the Center for 17 Nuclear Regulatory Analysis.
But we are familiar with that 18 work mostly because we have been keeping track of the work i
19-related to Yucca Mountain, and a lot of that work we judge 20 as quite innovative and very important, and so we classify l
21 it -- or we decided to include that under research.
- And, 22' so, of course, we have had regular presentations and 23 interactions with staff of NMSS.
i 1
24" We also had a meeting where we had some briefings 25 from the Department of Energy with regard to their waste l
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32 1
management research.
This is not the Yucca Mountain, but 2
this is a program that was done between their Office of 3
Research and the Waste Management Division to sponsor basic 4
research.
And we also heard from EPRI, the industry side of 5
the house, on how they conduct their research program.
l 6
So that is the background, just so you know what 7
we did to come to some of the observations that we had --
8 that we have listed.
9 The observations with respect to NMSS then, as I 10 very quickly summarize out of the report, it is obvious that 11 the Department of Energy has the big job in terms of coming 12 forward with a license application for Yucca Mountain and 13 their research program, obviously, has to show that.
So 14 that their research budget is much, much larger than the NRC 15 budget.
16 We took -- one of the reasons we took a look at 17 EPRI was because EPRI has a very -- also a very modest 18 research program, and we were interested in the way they 19 handle it.
Of course, from the industry side, they have 20 lots of flexibility, they have almost no constraints, and so 21 they use performance assessment to prioritize the topics 22 that they go after and then they simply go out and find the 23 best person that they can to do the work that they want to, 24 and they contract with that person.
And, clearly, the NRC 25 simply can't have that kind of flexibility.
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1 But one of the observations that we did have was 2
that the research and technical assistance programs within 3
NRC really do have to be focused and flexibility and carry 4
the respect of the scientific community.
And, obviously, I
I 5
the NRC has to continue to have national and international 6-stature in the whole waste management area.
i 7
CHAIRMAN JACKSON:
Let me ask you a question.
I 8-noted that you made a number of some specific
- 9 recommendations and one of them was, this goes back to 10 high-level waste, you said -- well, and more broadly, i
11 actually.
You said that the performance assessment model 12 should be structured to represent repository performance as 13 realistically as possible.
14 I mean is there an implication there that the NRC 15 is not using realistic assumptions or realistic models?
Or 16-is.this just kind-of an overall --
17 DR. HORNBERGER:
No, actually, I think that we did 18 have that comment in a previous letter and we continue to 19-believe that the NRC, the staff must continue to strive to 20 be as reasonable as possible -- as realistic as possible, 21 excuse me, and to ferret out any conservatism that are 22 built in and make sure that they are appropriate 23-conservatism.
24 CHAIRMAN JACKSON:
So it is really a question of 25 following a line with some modulation, l
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34 1
DR. HORNBERGER:
Yes.
2 CHAIRMAN JACKSON:
-- as opposed to that they have 3
been on entirely the wrong track?
4 DR. HORNBERGER:
Oh, no.
In fact, quite the 5
opposite.
We think that they are very definitely on track.
6 CHAIRMAN JACKSON:
Okay.
I just wanted to be 7
sure.
8 DR. HORNBERGER:
I think the first bullet in terms 9
of recommendations, really, really should -- NMSS should 10 continue to focus their technical work.
11 CHAIRMAN JACKSON:
Okay.
12 DR. HORNBERGER:
They have been doing an excellent 13 job, by the way, in using the TPA, their total performance 14 assessment code, to look at the priorities, to continue to 15 assess the key technical issues and the sub-issues.
And 16 they have used it -- I had a chat with Margaret Federline, I 17 guess in April, on this, and she said, yes, they do look at 18 these results and they do have -- they try to maintain as 19 much flexibility as they can to redirect work at the Center 20 as appropriate.
So --
21 CHAIRMAN JACKSON:
Well, a concern I had had 22 relative to the TPA was the data that the NRC had available 23 to it, because in order to be realistic, you have to have 24
-data that tells you something about the site you are trying 25 to model.
Do you have any comments or concerns in that MIN RILEY & ASSOCIATES, LTD.
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particular' area?
2 DR. HORNBERGER:
Yes.
I mean, clearly, of course, 3
the DOE, their TSPA suffers from exactly the same problem.
4 So it is not just NRC TPA, but it is the DOE and, of course, 5
EPRI uses their total performance model and they have 6
exactly the same kind of' constraints.
7 I think that there are clear areas where the 8
database is sketchy, shall we say, and I think that Ray 9
probably will-highlight at least a couple of areas where we 10 really -- we think that probably the database with regard to 11 engineered systems, in particular, definitely needs work.
12 The NRC obviously can't' afford to collect all of
-13 those data, they have to be very select in terms of what 14 they focus on.
And I think that is the focus and 15 flexibility issue that we raised with respect to the 16 high-level waste.
1 17 CHAIRMAN JACKSON:
Is there more opportunity with 18
. making use of data that DOE itself generates, but in our --
19-in the models?
1 20 DR. HORNBERGER:
Yes.
Oh, absolutely.
Charles 21 and I just were up on the seventh floor at lunch and had a 22 demonstration of the three-dimensional geological model for j
23
-- that was developed by DOE.
And the NRC is verifying this l
and basically considering what the criteria will be for them 24 25 to accept it into their own use.
And so DOE invested a huge I
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amount of money to develop a tool that is I think going to
'2 be very useful for the NRC, as one' example.
l 3-CHAIRMAN JACKSON:
Thank you.
4 DR. HORNBERGER:
So, in terms of the 1~
5 recommendations, as I said, the continued focus of the 6
technical. work by using the TPA.
We have had clear evidence l
7 over the past several meetings that the DOE design continues 8
to evolve and we anticipate that it will evolve as we go 9-into the future with changes.
Therefore, the flexibility l
C10 with the Center has to be maintained in terms of, definition 11 of the-tasks.
As I said, the main flexibility that we 12 observed with EPRI is that they had freedom to engage l
13 anyone, any expert in the world without constraints as to 14 prior-work with DOE or anything else, and NRC doesn't have 15 that.
16 Nevertheless, we do feel strongly that outside 17 experts, engaged appropriately in a surgically precise 11 8 manner, again, can enhance both the acceptability, and when l
19 you get' advice from world experts, really leading experts in 20 the world, I think that it does have -- it reflects j
21 credibility onto the program by having these excellent 22 people from the outside concur with you.
23 And there have been a range of letter reports and 24' this last bullet really comes from a letter that we wrote to i
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where we, in fact, again, identified, because of this switch 2
-- not a switch, but the enhancement of interest in the 1
3 engineered part of the system of the repository, which we 1
believe is going to continue to become ever more important
-4 5-as we -- as DOE goes forward, that.the NRC staff really does 6
have to make sure that.they have the right capabilities, 7
either here or at the Center, or that they have the 8
flexibility to engage help as they need it.
9 The next observation with respect to NMSS, again, it is really a repeat in the sense of the point that I just 10 11 made.
It is imperative that'the outside'world not view NRC 12 analyses as overly simplistic.
And, again, we think the 13 ACNW believes that one way to help out in this is to engage 14 prominent waste engineers and scientists in the resolution
'15 of waste management problem.
16 And, of course, we understand that funding has 11 7 been an issue for years.
We discussed, I think, a year ago about the decrease in funding for certain -- curtailing work 18 19 on certain KTIs and this can throw monkey wrenches, 20 obviously, into programs, and people do have to live with 21 that.
We don't have an infinite resource here.
But, at any 22 rate, we think that the Center funding has to be such to 23 ensure that this ongoing effort is maintained.
24 Our observations with respect to the Office of 25 Research, really, the first bullet here on the observation ANN RILEY & ASSOCIATES, LTD.
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has to do with priority setting.
We heard the presentations 2
on'the research.
We are impressed by the work that is being l
L 3
done by the_ Office of Research.
But we thought that setting 4
priorities and how priorities were set were a key, and it 5
- was unclear to us in our discussions whether the current 6
structure for setting priorities was what we would consider 7
rigorcus.
8 We were told that certainly the staff experience 9
and knowledge had gone into setting the priorities, and 10 these people have had many years experience, and there is 11
' reason to believe that they are on top of things.
12
'Nevertheless, whenever -- especially with such restricted 13 resources, you really want to make sure that you focus on 14 the priorities.
So our recommendation to the Office of 15' Research, that we see a need for a structured organization 16 for identifying the priorities and make sure that peer 17 review is involved, and that it focuses on the users, 18 because, after all, it is an applied program, if you like.
19 So that summarizes our input on research.
20 CHAIRMAN JACKSON:
Thank you.
21 Dr. Wymer.
22 DR. WYMER:
Thank you.
My presentation today is 23 on the near-field environment, performance of engineered 24 barriers,-particularly as they relate to the Yucca Mountain 25 Repository.
And a big part of what I will present is based ANN RILEY & ASSOCIATES, LTD.
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{
i-1 on a" working group meeting'that we held June loth and lith, 1
2 a two-day. meeting where we' brought in experts from outside, 3
as well as DOE.and NRC and from the Center, and'had 4
presentations..
5 We'think this topic is-particularly important 6
because'of the increased attention paid by DOE to engineered 7
barrier: system performance.
And it-is important to the NRC, 8
of-course,.because.they have to keep up,with things and have.
9 to license.that repository,;so they have to understand what l
10 DOE'has done.
11 We also got a' lot of input from the workini3 group 12 with respect to what are the really important technical 13
-issues, and there was a lot of sort of ad hoc discussion 14 that wasn't even on the agenda that raised some areas that 15' I'_ll gettinto which we thought were particularly important i
h 16
-and relevant.
17 So, going.to the next viewgraph, we have'some 18 general observations to start with, then I will give some
'19 specific insights that.were obtained out of the working
{
20-group.
First, the. Yucca Mountain Repository is different 1
-21 from other-planned repositories around the world in that it 22'
.is.in an unsaturated and oxidizing environment,'which really
- 23 ;
changes a lot of things with respect to corrosion, with' i
24.
respect to chemistry.
Whereas, most of the repository 25
. designs areLin a saturated environment which is primarily a l
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1 40 1-reducing environment, the chemistry is quite, quite 2
'different.
So that's.an important difference and it puts l
3 Yucca Mountain kind of apart from all the other repository 1
4 design considerations.
5 The'other thing that George mentioned is that it's 6
like shooting a running deer.
The EBS design continually 7
changes as the Department of Energy picks up on new facts, 8
new importances, new emphases arise, and so every time we 9
hear from them'there's something new and it's generally in 10 the right direction and we are glad to hear it, but it does 11.
make it'a moving target so it's kind of hard to keep up with 12 the design.
13
. Consequently and concurrently that means that the 14 NRC Staff has to be quick on its feet and has to have 15 flexibility to stay abreast of this evolving situation.
16 The Department of Energy talks about a robust 17
' depository and our understanding of what robust means is 18 that it is simply enough that it is not going to collapse 19 under its own' complexity and that the defense barriers, that 20 barriers are decoupled'so that if one fails, everything 21 doesn't' fail, so robustness implies as much simplicity as 22 possible and as much decoupling as possible of one barrier
'23 from another so that you don't have in the language of the 24 reactor you don't have common mode failure.
25 We think it is important, and we are not sure we ANN RILEY & ASSOCIATES, LTD.
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see good evidence of this out of the EBS design options, we
-2 think it is important that there be a top-down systems 3
engineering approach rather than a bottoms-up.
By that we 4
mean that you need to set the overall goals and the overall
)
5 design features at the beginning and build toward those i
6 rather than seeing a lot of details emerge and let those 7-form your design.
There is probably quite enough of that going on as there should be and attention should be paid to 8-9 that in the NRC's review of the situation.
10 Then something that emerged that wasn't really on 11 the working group agenda but there was a lot of discussion 12 that it emerged as a very important issue had to do with the i
i 13 preclosure issues of the repository.
That thing may stay 14 open for 100 years.
DOE talks about 100, 200 years -- they 15 get a little unrealistic in my view, but nonetheless they 16 -
are talking a long time into the future keeping that 17 repository open and during that time there are a lot of' 18 issues that come up having to do with heat loading and 19 retrievability of waste packages and during that time the 20 repository performance features can be confirmed or denied 21 and the NRC needs to be certain I think that it pays 22 attention -- we think -- that it pays attention to the 23 preclosure aspects of the repository development, which one 24 of our expert panelists said should be an evolving thing.
25 He even advocated continual changes in the design ANN RILEY & ASSOCIATES, LTD.
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42 1
.of the waste packages and then some features of the
~2-repository as information is gained over the 50 to 100 years 3
before closure -- so this is an area where little attention 4'
has been paid by either DOE or NRC as far as we have been 5
informed to date and we think that it deserves attention.
6 On the next exhibit here, we get into I guess 7
near-field environmental issues, and by that we mean 8
anything from the concrete liner of the drift on in --
9 anything inside there is what we define as the near-field.
10 One ofLthe things that came out and our first 11 reaction, my first reaction to it and I think maybe the 12 committee's, was that gee, this is kind of obvious, why are 13 yo,u telling us this, is that it is very important how much 14 water comes in and how much contacts the waste.
Well, you 15 know, that is what we call a privileged glimpse at the 16 bleeding obvious, but when you think about it and you think 17.
about what DOE is planning,-it turns out to be worth' paying 18 attention to.
They are talking about a drip shield.
They 19 are talking about potentially backfills and they are talking 20 about the effects on solubilization and transport of fission 21 products and all this relates to water, so anything you can 22 do to control the water is important and that is beginning 23 to get a fair amount of attention, and I will say a little 24' bit more about it.
~25 There was.some concern expressed about the ANN RILEY & ASSOCIATES, LTD.
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if.
43 1
abstraction from the PA models, from the near-field process 2
level.models, into a PA model.
The concern was, first, is 3
the fullblown model adequately supported by data, a point 4
-that we dealt with a little bit earlier, and second, is the 5.
abstraction to this more simplified model done well?
Does l
6 it really incorporate all of the salient points in the i
7 process level models? -- so.we thought that attention needed 8
to be. paid to that.
Now there is a great deal'of at'tention 9
going into that but nonetheless it was brought up and we 10 thought it deserved mentioning here.
11 The near-field chemistry is near and dear to my 12 heart and there is a lot of chemistry discussed, even though 1
13 one of the participants characterized the meeting as a 14-
" corrosion meeting" -- he was a corrosion expert and my 15 answer to.that was t( a hammer everything is a nail -- and 16 he felt it was a corrosion meeting.
17 Actually, there is a lot known about the chemistry 18 of the water entering the repository but~there is not much 19 known at all about what happens to that water when it starts 20 hitting things inside the repository, especially at I
21 mechanistic level.
There's a lot of empirical and anecdotal 22' information but there is not a lot of true basic 23 understanding of the chemical reactions that the in --
1 24' flowing water will bring about as it contacts in particular 25 the fuel material.
Il l
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Those reactions are extraordinarily complex and 2.
are poorly, poorly understood on a fundamental level.
3 The next exhibit here deals with corrosion.
As I 4
said, one of the participants felt it was a corrosion 5
meeting and it was very heavy on corrosion, and partly that 6'
is because there is a lot of expertise on corrosion both 7
within the NRC and its contractors and at DOE.
8 There are good people doing good. work on corrosion 9
and there is a lot of interaction between those people but 10 you need to distinguish, we feel, between a good expertise 11 and a basic understanding of corrosion issues and specific 12 understanding about specific corrosion problems relating to 13 specific materials.
That gets into the next point on this 14 exhibit, which has to do with the wonder alloy C-22.
That 15 is a high nickel based allow which has. received a great deal 16 of attention.
It is extremely corrosion resistent.
17 I call it'a wonder alloy.
It is sort of a --
18 without tongue-in-cheek, it's a very good material.
19 However, the information base with respect to corrosion is 20 limited with respect to.the amount of time that people have 21 been studying this material -- something less than two 22 decades, which is a whole lot less of course than people 23 have.1,ooked at iron and titanium and other kinds of alloys, 24:
so there was a lot of stress being put on the use of this 25-alloy and it probably will play a very important part in
. ANN RILEY & ASSOCIATES, LTD.
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45
'l DOE's analysis.
2 CHAIRMAN JACKSON:
Commissioner Diaz.
3 COMMISSIONER DIAZ:
Just out of curiosity, has 4
anybody been trying to look at single crystal alloys at all 5
because of their tremendous resistance to corrosion and 6
diffusion?
7 DR. WYMER:
No.
As far as I know, that has not 8
taken place.
Of course, that would be a mighty big single 9
crystal but 10 COMMISSIONER DIAZ:
I have seen them big enough in 11-Russia.
They do make them big.
12 DR. WYMER:
No, that has not -- that wasn't 13 brought up and we're not aware of anything.
14 COMMISSIONER DIAZ:
Interesting.
There is a 15 program from STIO that gives a nickel alloy, single crystal
-16 alloys, as being done now, last four, five years.
- 17
.DR. WYMER:
I know that single crystals are 18 sometimes much more resistent to corrosion.
19 COMMISSIONER DIAZ:
Much more -- and they're t' ying to put them in jet engines.
20 r
21 DR. WYMER:
Even with the macrocrystalline 22 materials the corrosion resistance is high for this 23 material.
It is bhsed primarily on the existence of an 24
' oxide layer because this alloy like all other metals --
25 COMMISSIONER DIAZ:
Right, right ANN RILEY & ASSOCIATES, LTD.
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46 1
DR. WYMER:
-- most other metals is not --
2 COMMISSIONER DIAZ:
And there would be no 3
diffusion and so it is a tremendous advantage.
4 DR. WYMER:
Despite the fact that this loc /.a very 5
good, one or two of the corrosion experts raised concerns 6
having to do with localized or crevice corrosion that might 7
occur when you get -- by evaporation concentrations of 8
chloride iodine and other kinds of things that~ enhance 9
corrosion.
10 One of the speakers brought up a very interesting 11 observation which deserves to be proven or disproven.
That 12 is, he said that there is for C-22 a temperature regime 13 during which corrosion can occur.
Above that temperature 14 and below a temperature it is practically nonexistent.
I 15 mean the corrosion is very low, which suggests that by-16-judicious arrangement of conditions you can avoid that 17 temperature regime for long periods.of -- to exist for long
.18 periods of time and thereby greatly enhance the-lifetime of 19 the material.
- 20 So that they're knocked down or verified.
21 CHAIRMAN JACKSON:
Yes.
22 COMMISSIONER McGAFFIGAN:
How quickly can you 23 knock down or verify that?
Is it relevant to licensing of 24 Yucca Mountain, or is it a 20-y(ar research project?
25 DR. WYMER:
I can't answer that question ANN RILEY & ASSOCIATES, LTD.
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47 authoritatively, but my feeling is though that you could I
1 2
certainly ferret out a major difference between being in the 3
temperature regime and being out of the temperature regime 4
in a fairly short period of time.
5 COMMISSIONER McGAFFIGAN:
Where is the temperature 6
regime.where corrosion may occur according to this?
7 DR. WYMER:
It's fairly low.
8 DR. HORNBERGER:
It's 100 to 120 C.
9 DR. WYMER:
Maybe 80 to 120 or something like 10 that.
It's fairly low.
11 COMMISSIONER DIAZ:
I'm sorry I'm smiling.
We 12 were working at 1,400 degrees Kelvin.
13 DR. HORNBERGER:
Well, it won't get quite that 14 hot.
15 DR. GARRICK:
At a little different time constant.
16 COMMISSIONER McGAFFIGAN:
Could I also -.if 80 to 17 120 degrees centigrade is where tne risk range is, is it 18 easy to -- I mean, presumably you wouldn't_want to be above 19 that, that would be difficult to control, or maybe that is 20 where you end up, if there's a lot of heat in the mountain 21 maybe you end up above 120 and never have to worry about 22 coming below it.
But how -
which way were you going to try 23 to control?
24 DR. WYMER:
One of the -- I don't know, but one of 25 the considerations is that if these alloys are as good as l
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48 1
they are claimed to be, then even in the corrosion regime 2
they may well be stable for times long enough that high 3
temperatures due to the decay heat are not important 4
anymore, in which case you might drop down below that.
So 5
that's one consideration.
6' We need to know more about this particular point, 7
because it is apparently important.
8 Another point was brought up with respect to 9
corrosion-of the outer layer.
The C-22 is a thin inner 10 protective layer in the waste package.
There's a much
- 11 thicker outer iron or steel layer which is really the main 12 container for the waste.
And that will corrode.
13 One of the experts brought up the fact that well, 14 suppose you get a hole in that container and it rusts and 15 the' rust is on the inside rather than the outside,.there's a 16 volumetric change as you go from the metal to the oxide, and 17 it'll expand.and crush what's inside.
And it may in fact 18 bend, break, fracture, and some other ways do harm to the 19 inner container, C-22 or whatever it is, whatever's chosen.
20 And that has not been addressed in detail.
21 Also, the.effect, when this happens, when you get 22.
iron oxidation, the effect of ferric ion on corrosion is the 23 important factor.
24 Then one of the experts brought up the issue of 25 weld integrity.
He says we've got to have a couple miles of ANN RILEY & ASSOCIATES, LTD.
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1 l
49 lweldsthere,andnobodyreallyknowsmuchaboutcorrosionof 1
L 2
They know a lot about corrosion of massive L
1 3
materials, but. welds are a horse of another color, and they o
4 always behave differently from the bulk material.
5 i
Am I overrunning my time?
6 I
CHAIRMAN JACKSON:
No.
Go ahead.
7-DR. WYMER:
So the point was brought up that it's important to pay attention to some of these more practical 8
9 aspects like weld integrity and their impacts on long-term 10 performance of the waste package, waste canisters.
11 Then the whole issue of backfills is an important 12 one.
You can control ingressive water with backfills to a 13 certain extent You can control chemistry in the repository 14 by using certain kinds of backfills having reducing 15 properties or chemical properties to retain elements that 16 might otherwise transport rapidly out of the container.
17 And then finally some of the experts question the 18 use of taking credit for the fuel cladding, the Zircaloy l
19 cladding on the fuel as part of what you rely on to prevent l
20 release of the fission products, and indeed we said well, 21 we're still thinking about that.
We're not sure.
22 CHAIRMAN JACKSON:
Doesn't that also put 23 constraints relative to whether damaged fuel could go into a 24
. repository?
25 DR. WYMER:
Sure, it does.
Sure.
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CHAIRMAN JACKSON:
Because that issue has come up.
2-particularly since the repository is, you know, it's
- L primarily for commercial fuel, and the issue is there, but 4
also for other' spent fuel.
5 DR. WYMER:
Sure.
6 CHAIRMAN JACKSON:
And then the issue of the 7
condition of the fuel, which includes its cladding comes 8
into play.
9 DR. WYMER:
That's right.
l 10' CHAIRMAN JACKSON:
And the impact on the overall.
l l
11 DR. WYMER:
Yes.
Bending or cracking or a~ny of 12 these things is important.
Yes.
i 13 CHAIRMAN JACKSON:
Okay.
14 DR. WYMER:
Then the final point was -- area that I
15' was discussed was the release of fission products and 16' actinides from the fuel itself and the transport of those 17 materials, and one of the invited experts particularly
.j 18 pointed'out the fact that when you let the water reach the 19 fuel and the water is saturated with oxygen, as it will be 20-under normal conditions, then you're going'to get. oxidation 21.
of the UO2 to some higher oxide,.and also the radionuclides, j
22' of which there'll be about 3 or 4 percent in that fuel, can 23 also -- some of those also,can oxidize, depending on what 24 they are.
Because normally they'll be in an oxidation state 25 governed by the fact that they were born in UO2 and there i
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l 51 1
.was that much oxygen available and no more.
2 So the formation of these oxidation products could in fact affect the release rates of the fission products and 3
actinides and therefore the source term ultimately for the 4
5-dose.
6 And finally there was the issue of secondary l
7 phases'and of colloid formation.
The secondary phases is 8
not exactly the same as the formation of oxides.
In this 9
. case they were talking about specific stable long-term i
10.
stable secondary phases that would incorporate inefficient 11 products or actinides within their structure.
And this 12 could dramatically change their release of fission products, 13 actinides, but not much is known about that, and there is no 14 good thermodynamic data base to use as a basis for 15 calculating what the stable phases might be.
16 And finally colloids and pseudocolloids are I 17 think clearly going to be of importance, and that was 18 discussed at some length.
A colloid is something'like a 19 plutonium polymer.
A pseudocolloid is something like clay or iron which forms a colloid which then absorbs physically f
20 l
21 or chemically a fission product or an actinide, which then 22 would' move the way the colloid moves rather than as the way 23 an ion in that material would move.
And we felt that 24 attention needed to be paid to those kinds of things because i
25
'they could have a dramatic effect, the secondary phases, for ANN RILEY & ASSOCIATES, LTD.
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retarding movement, colloids for enhancing movement.
2 And then we thought that we wanted to know more 3
about -- and I'm sure more is known, but we don't know it --
4 more about the rank ordering of the importance of these 5
various barriers to movement in the repository one with 6
respect to another so that we know what's the 800-pound 7
gorilla and what we don't care about.
8 CHAIRMAN JACKSON:
Sure.
9 COMMISSIONER McGAFFIGAN:
A fairly fundamental 10 question comes from this presentation and our presentation 11 by the staff a few weeks ago about performance assessment in 12 this area, and that is how much of a grip are we going to 13 have on these engineered-barrier issues by the time we're 14 licensing, and will a conservative licensing process with an 15 array of expert opinion have to ultimately perhaps not guess 16 that the C-22 is going to be quite as good as claimed, and 17 how do we -- how is this all going to come down.
The staff 18 seems to have -- and I don't have the exact transcript of 19 the meeting in front of me -- but some real concerns about 20 overemphasis on engineered barriers at the current time in 21 some of the DOE work.
So I wonder if that's shared.
22 DR. WYMER:
Why don't you, John?
23 COMMISSIONER McGAFFIGAN:
Well, either one of you.
24 DR. WYMER:
I'll take his lead.
25 DR. GARRICK:
Well, it is a difficult problem.
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.li b
But I recall.the same anxieties when we first started 2-looking at the" reactors in terms of the contribution of L
3 mitigating systems, that there was great skepticismLabout.
L 4
our ability to be able to quantify, for example, the worth 5.
of a containment system or a high pressure injection system,
'6-Land much progress'was made on~that in a relatively short Is.
7.
period of time.
8 And I think when we started focusing on that, and' L
9 we started dealing with the question of what is the real' 10 worth of containment, for example, because that was a til classic, similar argument,.that we don't know how mu'ch the 12 containment -- we can design'it to certain pressures and we
'13 can make it robust.
But it wasn't too long before we were T14 able.to put some quantification to the wh' ole process and 115
.suggest'that for some containments, the capacities of those
'16 containments were anywhere from'l-1/2 to 4 times their 17
. design basis.
And it was an extremely important E18 '
b'eakthrough-to get -- to begin to get'those' kinds of-feels r
- 19 and' senses of what the defense mechanisms were.
20-I think the same is true here.
I think that right 21 now it is new territory.
It is a different problem.
It is 22
- the processes involve extremely long time constants,
'23 They are serial for.the most part, rather than parallel.
u 124 They.are passive for the most part,-rather than active.
But l
l
- 25
!I am confident that if we just stop worrying about'it and I
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54 1
start focusing on dealing with the question of how.uch 2
value are we getting from a drip shield or backfill, or an 3
outer barrier, 100 millimeters of steel versus 50, or 50 4
millimeters of C-22 versus 20, I think we can -- I think we 5
will be surprised.
6 There has been a lot of advancements made in what 7
I would call structural mechanics from a probabilistic 8
perspective and I am more confident than most people.
9 COMMISSIONER McGAFFIGAN:
Could I follow-up?
You 10 mentioned the word time constants, and one of the issues --
11 I mean if you take -- if, hypothetically, we are working 12 with a 10,000 year period, which is what we worked with, and 13 that may not -- there are longer periods.
One can consider 14 the Academy talked about longer periods.
15 But one of the problems with these time constants 16 is you can -- if you really believe the analysis for 10,000 17 years, you sort of -- everything is nice and tightly 18 contained right there at the site, and there is no -- there 19 is no source term going very far.
And how robust that 20 judgment is is going to be the heart of the licensing 21 process, if, indeed, there is a lot of emphasis on the 22 engineered barrier.
23 But at some point these things break and we will 24 have to look at what happens once the geologic system is 25 providing the containment.
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1 DR. GARRICK:
Right.
2 COMMISSIONER McGAFFIGAN:
And how things go.
But 3
to some degree, because of the time constants, you can get 4
into a situation where, if 10,000 years is the licensing 5
period, is the period for analysis and deciding whether to 6
grant a license, the problem gets defined away, and then it 7
just pops up at 60 or a 100 or --
8 DR. GARRICK:
The compliance problem gets defined 9
away, but the risk problem does not.
10 COMMISSIONER McGAFFIGAN:
Right.
11' DR. GARRICK:
Right.
12 DR. WYMER:
Well, I would like to throw in my two 13 cents on that.
We can identify, and I have, a half a dozen 14 areas of potential concern and things that deal with the 15 adequacy of engineered barriers.
But it is very possible, I 16 think likely, that by not particularly sophisticated 17 analyses, quite a few of these things will be laid to rest 18 as being below the horizon, and there will only be a few 19 that will stand out as peaks that we really -- that really 20-deserve attention.
And that's why we make the point that
-21 this rank ordering ~is -- early on, is important, because 22 those, things which even on a semi-quantitative or almost 23 qualitative' basis, you can rule out, reduce the field 24 substantially, or on the basis of the fact that DOE is not
-25 even going to rely on those things in the first place.
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a_______-_-_-___-_
56 1
So it-seems to me that there is a -- we are just 2
-before making a major simplification in what we need to be 3
concerned with.
And if attention is paid to these, some of 4
these issues that we have raised here, they can -- some of 5
these will just be thrown aside and they won't even turn out 6
to be.important.
7 COMMISSIONER McGAFFIGAN:
One last question.
8 Whose job is it to bring about that major simplification?
I 9
mean you are recommending it.
But is that DOE's job to 10 bring it about?
11 DR. WYMER:
It's DOE's job to recommend it.
It is 12 NRC's to be sure that.they are good recommendations.
13 DR. GARRICK:
Speaking of recommendations, as you 14 know, this_particular work is work in progress, and we 15 intend to send you a. letter and to make some 16 recommendations.
17 CHAIRMAN JACKSON:
Okay.
Dr. Garrick.
18 DR. GARRICK:
It's an interesting dichotomy.
The 19 essence of reactor safety is the presence of water.
The 20 essence.of repository safety is the absence of water.
You 21-would think we'could get it right somehow.
22 CHAIRMAN JACKSON:
Well, the presence of water can 23 also be a problem.
24 DR. GARRICK:
Well, in some reactors, a special 25 problem.
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'l CHAIRMAN JACKSON:
That's right.
i 2
DR. CARRICK:
And under some temperature 3
conditions.
j
~4 I want to talkia little bit about planning.
5-Planning is something you kind of really hate to do.
But 6
when you have done it, 7
CHAIRMAN JACKSON:
Oh, darn.
=8 DR. GARRICK:
-- you are really glad'you did it.
9 That's the case.
l 1
I 10 CHAIRMAN JACKSON:
Good.
Because it is over or 11' because --
'12
-[ Laughter.]
13 DR. GARRICK:
Well, partly because of your 14 leadership, we have moved in the direction of trying to
-15
. become much more formal in our planning.
The ACNW has
~
16 always attempted to prioritize and plan its activities for l
17 the forward year and years.
But it was -- this year was the l
18 first time we attempted to get a little more structure and a i
19.
little'more fo'rmal in the whole process.
20 We tried to lay down some rules that'were the 21 basis for our planning activity.
We wanted to be darn sure 22 that we didn't get ourselves so tied down to our plan that 23-we were not in a position to offer advice as a result of
'24 some major changes and we did not want to get in a position 25-that we couldn't respond quickly to change.
So we had that ANN RILEY & ASSOCIATES, LTD.
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as one:of our major commitments and rules for the planni 2
process.
l 3
The one thing that does come from a plan is the
~
4 ability to kind of look at yourself and measure against some 5
sort of a baseline, and we have been doing that.
We have 6
established the plan as input to our operating plan.
- And, 7
of course, _our operating plan has such metrics in it as 8
timeliness of our information, its quality, its efficiency, 4
9 its effectiveness, et cetera.
j i
10 Also, we, in this year, in a little more formal 11 manner, completed a performance evaluation of ourselves.
12 That was documented in a SECY document on June ~1st.
The l
13 status of our planning activity is that we were extremely j
i 14 pleased that the Commission also read that letter and j
15 responded directly to us, and those comments are very 16 helpful and have to do with the fact that perhaps our l
l 17 planning was a little too narrow in scope, maybe it didn't 1
18 match up with all of the elements'of our chi.rter, and we.
l l
19-intend to take those comments as source material for the l
20-planning activity that we will engage in'later this year.
21 We have received Commission requests for new work 22 as a result of exposing the plan.
For example, in the 23 low-level waste area, the issue that has already been 24 brought up this morning of' criticality at Envirocare and a 25 generic consideration of criticality in low-level waste ANN RILEY & ASSOCIATES, LTD.
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)
sitos is something we are currently addressing.
1 2
We have, certainly, been addressing the issue of 3
risk.
The comment was made to get outside of the box, if 4
you wish, and look at some topical issues like reactor 5-vessel handling and what to do about used reactor vessels.
6' The Trojan reactor vessel has been mentioned in particular.
7 And.,.of course, clearance levels'are another i
8 example of things that have been mentioned that we maybe 9
ought to be prepared to deal with.
And, of course, we have 10 to be cautious about managing our scope because we have 11 resource limitations just like everybody else.
And in 12 regard to that, there was a memorandum to the Chief 13 Financial Officer concerning additional resources for fiscal 14 year 1999 to give us increased confidence that we can, 15 indeed, respond to these requirements.
16 The Committee is very pleased to report that we have issued letters on all of our first. tier priority 17' 18 topics.
The first tier priority topics included such issues 19 as viability assessment and site characterization, 20 Eisk-informed, performance-based issues, engineered barrier 21 systems, decommissioning and research.
22 In kind of the spirit of accomplishments, we 23 provided recommendations and advice on a rather large number 24 of issues such as defense-in-depth.
We wrote you a letter 25 in October of last year.
Multiple barriers in March of this L
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year.
The use of PRA in the waste field, this was the issue 2
of what lessons can we carry from the vast amount of i
3 experience in the reactor field to the waste field, and we 4
wrote a letter on that.
And on the subject of the effects 5
low-level ionizing radiation, prompted by Commissioner Diaz, 6
and we wrote a letter on that.
7 One of the things that the Committee has been 8
relatively sensitive to and quite active in is trying to 9
heighten the awareness and the need for attention to the 10 engineered barrier system issue in high-level waste disposal 11 and the growing apparent dependence on engineered systems in 12
-- being in the demonstration of the performance of the 13 repository, and we have been very active in addressing that 14 issue.
15 One of the highlights of the year and, certainly, 16 one of the most technically stimulating activities we have 17-engaged in in the last couple of years was the working group 18 that Ray Wymer was the lead person on, that we had in early 19 June, and we think that working group activity generated 20 some extremely valuable source material for us to address 21 much more intelligently the issues surrounding increased 22 dependence on engineered barrier systems.
23 One of the things that the Commission has reminded 24 us to do from time to time is to be aware of international 25 activities in our work and in our gathering of source ANN RILEY & ASSOCIATES, LTD.
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61 1
material as a basis for our advice.
We have done a number 2
of' things in direct response to that.
One of the things we 3
certainly are pleased that happened is that we got a member 4
'of the Committee, namely, Dr. Fairhurst, who has a vast 5
amount of international experience and seems to know 6
everybody in this business, and that has been extremely 7
helpful in organizing a number of things, including a trip 8
that we -- and a meeting we expect to have with the German 9
RSK later this year.
l 10 Future activities, we expect to issue to you a major letter report on engineered barrier systems.
We also 11 12 expect to issue letters on such topics as post-disposal 13 criticality, the NUREG, 10 CFR Part 63, total system 14 sensitivity analysis.
In fact, we have completed that 15 letter at this me'eting.
16 The interesting issue of importance measures and i
17 the whole question of can you really do importance measures 18 for systems typical of repositories.
The issue of 19 decommissioning.
And, of course, we. expect to send pou some 20-advice on the viability assessment.
21 CHAIRMAN JACKSON:
Commissioner McGaffigan.
22 COMMISSIONER McGAFFIGAN.:
Could I ask one question 23 on the post-disposal criticality issue?
I know you got 24 briefed on this yesterday, and I understand you asked some l
25 penetrating questions.
If you go back to your risk-informed ANN RILEY & ASSOCIATES, LTD.
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definition of risk, the triplet model of risk, we have got 2
something there that is vanishingly small, although we 3
could, I guess, try to quantify it, and you questioned, and 4
I think appropriately, trying to quantify vanishingly small.
5 The consequences from the Oak Ridge' study, even if l
6 it happens, are not enormous.
And so the question, from a 7
regulator's perspective, and the reason you have been asked 8
the question, obviously, is we -- the Commission is asking 9
is~it'-- When is enough, enough?
10 DR. GARRICK:
Yes.
11 COMMISSIONER McGAFFIGAN:
Do you have -- not 12 trying to get the letter report out of your mouth right this 13 moment, but do you have an initial impressions as to when 14 enough is enough in this area?
15 DR. GARRICK:
Well, I do.
I think this is an
.16 ideal example of what we were talking about earlier, of an 17 analysis that should be risk-informed.
Even though, to do 18 it quickly,.we may be faced with a lot of uncertainties, I 19 suspect we still would learn a great deal about it.
We are 20 going to probably encourage that kind of an approach be 21 taken.
We are not very sympathetic to an extensive research 22 activity based on what we have heard so far.
'23 COMMISSIONER McGAFFIGAN:
Okay.
Thank you.
24 DR.oGARRICK:
We have mentioned the issue of 25 international technical meetings.
Dr. Fairhurst continues ANN RILEY & ASSOCIATES, LTD.
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to do that and be our ambassador, but we will enhance that a 2
little bit and see what he is up to when we all go to 3
Germany.
4 We expect to hold a stakeholder meeting in Yucca 5
Mountain vicinity to enhance public participation.
You 6
recall that that is one of our goals, is to offer advice on 7
how to enhance public participation.
And we expect, 8
finally, to conduct increasingly comprehensive' 9-self-assessments.
10 COMMISSIONER DIAZ:
Excuse me.
A few moments ago 11 you mentioned that you have already reviewed or considered, 12 or read about the clearance of materials and the potential 13 development of a rule.
Are you prepared to engage in this i
14 issue of the clearance of materials?
You don't mention in 15-your future activities.
16 DR. GARRICK:
We are prepared to engage.
I think 17 that's what advice committees are prepared to do.
18 COMMISSIONER DIAZ:
That's good.
19 DR. GARRICK:
It is not a comfortable issue and a
.20 lot of people would-just as soon that we not engage, but we
- 1 will.
We will. engage.
2 12 2 -
COMMISSIONER DIAZ:
All right.
23 DR. GARRICK:
I think that completes our 24 discussion.
We are sorry we ran over a little bit, I guess.
25 CHAIRMAN JACKSON:
Okay.
That's all right.
{
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COMMISSIONER McGAFFIGAN:
My only comment is I 2
think next time they are going to have him do risk-informed, 3
performance-based at the end of the agenda rather than the l
4 beginning.
5
[ Laughter.]
p
'6 CHAIRMAN JACKSON:
No, I told them they would have 7
all the time they needed.
You had all the time you needed.
8 DR. HORNBERGER:
Yes, we did.
9-CHAIRMAN JACKSON:
Well, let me just say that the 10 Advisory Committee's views on the matters you addressed 11 today are of tremendous value and importance to the 12 Commission-as we are trying to deal with the complexities of 13 a number of technical and policy issues.
14 You talked about risk-informed and 15 performance-based regulation, which you know is an important 16 area.
17 DR. GARRICK:
Yes.
18 CHAIRMAN JACKSON:
On the issues < associated with 19 L licensing activities for high-level waste repository,
' 20-decommissioning, which.is becoming increasingly important, 21-and other materials-related areas.
22 I want to commend you for the high quality of
- 23.
today's briefing and of the work you do, and just to tell 24 you that the Commission does appreciate'your efforts.
25 And so, unless there-is any further discussion, 1
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65 I
this meeting is adjourned.
2 DR. GARRICK:
Thank.you.
Thank you very much.
L 3
[Whereupon, at 3:16 p.m, the meeting was 4
concluded.)
5
.6 7
8 9
10
-11 12
- 13 14 15 16
'17 18 19 20 21
)
22 23 l
24 I
25 j
i L
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CERTIFICATE l
This is to certify that the attached description of a meeting of the U.S. Nuclear Regulatory Commission entitled:
TITLE OF-MEETING:
MEETING WITH ADVISORY COMMITTEE ON.
NUCLEAR WASTE (ACNW)
PUBLIC MEETING PLACE OF MEETING:
Rockville, Maryland DATE OF MEETING:
Tuesday, July 21, 1998 was held as herein appears, is a true and accurate record of the meeting, and'that this is the original transcript _thereof taken stenographically,by me, thereafter reduced to typewriting by me or under the direction of the court reporting company 3
-Transcriber:
W Reporter:_ Mark Mahonev l
m____..
~
~ ~ ~
~
R UNITED STATES
[
g NUCLEAR REGULATORY COMMISSION E
ADVISORY COMMITTEE ON NUCLEAR WA3TE l
Q, s,...../
WASHINGTON. D.C. 20555 J
July 10,1998 i
MEMORANDUM TO: John C. Hoyle Secretary of the Commission
- ~h FROM:
John T. Larkins, Executive Director y
[
Advisory Committe on Nuclear Waste
SUBJECT:
ADVISORY COMMITTEE ON NUCLEAR WASTE MEETING WITH THE U.S. NUCLEAR REGULATORY COMMISSION, JULY 21,1998 -
SCHEDULE AND BACKGROUND INFORMATION The ACNW is scheduled to meet with the NRC Commissioners betWeen 1:30 - 3:00 p.m. on Tuesday, July 21,1998 to discuss the items listed below. Background material related to these items is enclosed.
i INTRODUCTION - Chairman Shirley Ann Jackson 1:30 - 1:35 p.m.
PRESENTATIONS - Advisory Committee on Nuclear Waste (Presenter and relevant letters listed under each topic) 1.
Risk-informed, Performance-Based Regulation 1:35 - 1:50 p.m.
- B. John Garrick, Chairman, ACNW
- 3/26/98 itr. to Chairman Jackson: Risk-Informed, Performance-Based Regulation in Nuclear Waste Management 2.
Interim Guidance in Support of the Final Rule 1:50 - 2:05 p.m.
on Radiological Criteria for License Termina-tion
- Charles Fairhurst, ACNW
- 4/29/98 letter to Chairman Jackson: Comments and Recommendations on Interim Guidance in Support of the Final Rule on Radiological Cri-teria for License Termination
1
-2 3.
' NRC Waste-Related Reseach (work in progress) 2:05 - 2:20 p.m.
- George Homberger, Vice-Chairman, ACNW
- 10/8/97 letter to Chairman Jackson: Com-j ments on Performance Assessment Capa-1 bility in the NRC High-Level Radioactive Waste Program
~
4.
^ Near-Field Environment and Performance of 2:20 - 2:35 p.m.
Engineered Barriers (work in progress)
- Raymond G. Wymer, ACNW Working Group Meeting June 10-11,1998
- 3/6/98 letter to Chairman' Jackson:. ACNWs Support for the NRC Staffs Approach to Assessing the Performance of Multiple Barriers
- 5.
~ACNW Plans, Priorities and Accomplishments 2:35 - 2:45 p.m.
- for FY 1998 and FY 1999 Plans and Priorities (Progress Report)
- B." John Garrick, Chairman, ACNW
- 12/23/97 letter to Chairman Jackson: 1998
- Strategic Plan and Priority issues for the ACNW-
- 3/26/981etter to' Chairman Jackson: Commis-sion Comments on the ACNW Strategic Plan and Priority issues CLOSING REMARKS - NRC Chairman 2:45 - 3:00 P.M.
~
' cci ACNW Members
- ACNW Staff
0 i.
j l
l j
l List of ACNW 1e**ar Renorts Issued Ri=ce I==* Comm8 he Bria 7 December 23,1997 Letter to Chainnan.
Subject:
1998 Strategic Plan and Priority Issues for the
- Advisory Committee on Nuclear Waste.
March 6,1998 Letter to Chairman.
Subject:
ACNW'S Support for the NRC Staffs Approach to I
-Assessing the Performance of Multiple Barriers
~ March 6,1998 Letter to Chainnan.
Subject:
NRC High-Level Waste Issue-Resolution Process and Jssue Resolution Status Reports -
.l March 26,1998 ' Letter to Chairman.
Subject:
Commission Comments on the ACNW Strategic
' Plan and Priority Issues -
March 26,1998 Letter to Chairmam
Subject:
Risk-Informed, Performance-Based Regulation in.
iNuclear Waste Management
" April 29,1998 Letter to Chairman.
Subject:
Comments and Recommendations on Interim '
Guidance in Support of the Final Rule on Radiological Criteria for License Termination
' April 30,1998 Memorandum to R.L. Scale. Subjecti ACNW's Contribution to the ACRS' Report to the Commission on NRC Safety Research
- June 19,1998 Letter to Chairman.
Subject:
ACNW Comments on NRC's Review of the DOE
'I Viability' Assessment -
June 24,1998, Report to the Commission.
Subject:
Review and Evaluation of the NRC Safety r Research Program (Joint ydth ACRS).
i k---_um._n-----------------m-- - - - - - - - - - - - - - - - - - - -
I 2
3.
NRC Waste-Related Reseach (work in progress) 2:05 - 2:20 p.m.
- Gecrge Hornberger, Vice-Chairman, ACNW
- 10/8/97 letter to Chairman Jackson: Com-ments on Performance Assessment Capa-bility in the NRC High-Level Radioactive Waste Program 4.
Near-Field Environment and Performance of 2:20 - 2:35 p.m.
Engineered Barriers (work in progress)
- Raymond G. Wymer, ACNW
- Working Group Meeting June 10-11,1998
- 3/6/98 letter to Chairman Jackson: ACNWs Support for the NRC Staffs Approach to Assessing the Performance of Multiple Barriers 5.
ACNW Plans, Priorities and Accomplishments 2:35 - 2:45 p.m.
for FY 1998 and FY 1999 Plans and Priorities (Progress Report)
- B. John Garrick, Chairman, ACNW
- 12/23/97 letter to Chairman Jackson: 1998 Strategic Plan and Priority issues for the ACNW
- 3/26/98 letter to Chairman Jackson: Commis-sion Comments on the ACNW Strategic Plan and Priority issues CLOSING REMARKS - NRC Chairman 2:45 - 3:00 P.M.
cc: ACNWMembers ACNW Staff
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_ - _ - - - - - - - - - - - - - ~ ~ ~ - - ~
o{
UNITED STATES
[-
i NUCLEAR HEGULATORY COMMISSION a-
. ADVISORY COMMITTEE ON NUCLEAR WASTE 8
. WASHINGTON, D.C. 20006 March 26,1998 a
i I
(.
. The. Honorable Shirley Ann Jackson Chairman -
U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001
Dear Chairman Jackson:
I
SUBJECT:
. RISK-INFORMED, PERFORMANCE-BASED REGULATION IN NUCLEAR WASTE MANAGEMENT i
The Advisory Committee on Nuclear Waste (ACNW) welcomes the opportunity to provide input L to the Commission on its draft white paper on risk-informed, performance-based regulation (RIPBR) and to clarify the issues and concepts associated with implementing a risk-informed regulatory process. The ACNW supports the development of a basic document that provides a common terminology for the RIPBR approach and that elucidates how the associated concepts can be applied to both reactor and materials regulation across the agency. Moving to an RIPBR approach will help to develop more efficient and effective regulatory measures that '
focus directly on public safety and will provide a basis for optimizing the regulations The ACNW believes that it is essential to develop a broad understanding of RIPSR throughout -
the agency.: Because of the fundamental technical and regulatuy differences among reactor.
systems, waste management and disposal systems, and nuclear materials management systems, it is important that the concepts articulated in the white paper be sufficiently general to encompass all of these activities and regulations. Many of the concepts in the paper are
- oriented toward reactor applications.- The ACNW believes that the context or framework should be broadened for applying RIPBR to the management of radioactive waste and nuclear materials. The ACNWs recommendations and comments that follow are intended to help A
provide such a framework.
Cae-4=na " tr-- -. Nuclear W--*- D8-r - -'..d P--
2= A==?!-^ ="=.e
~ The primary differences between nuclear power plants' and waste disposal facilities are the type
' of facilities involved and the nature and timing of the events that can lead to a threat to public safety. The events in the nuclear plant risk scenarios are related pnmarily to short-term equipment and human error problems, while in waste disposal facilities, they are related pnmarily to long-term physical processes.1 Waste release events generally take place over i
hundreds and thousands of yeam, while times of concem in a nuclear plant may be fractions of I
a second or a day. Containment in a nuclear waste facility is provided by both natural and i'
- generally passive engineered systems, while in a nuclear plant, except for basic structures and atmospheric dispersion, active systems and short-term operator response dominate the mitigation of accidents. Monitoring capability differs greatly between the two. In general, 7
l 9
L_____
______'____.___'_.__'________E.__.____i__________.-___.
2 monitors for reactor performance are on-line with short response times. For waste facilities, there are extreme limitations on monitoring reliability because of the very long times involved and the general difficulty in measuring parameters affecting an eventual threat to public safety.
Differences between nuclear plants and waste disposal facilities point to the need for sufficiently fundamental concepts and definitions that embrace the full spectrum of activities regulated by the NRC.
Definitions of Terms and Concepts Risk and Risk Assessment.
- The Committee believes that the definition of risk in Section 3, page 2 of the white paper is too
- narrow. Risk measures need to be interpreted in terms of a fundamental set of principles that serve the broad scope of activities regulated by the NRC, The ACNW recommends adoption of the triplet dersnition of risk' because it defines risk at a sufficiently fundamental level to apply to the wide variety of nuclear materials applications that the NRC regulates. This definition may be incorporated in a section added to the white paper before the numbered paragraphs. The triplet definition takes the view that when one asks, "What is the risk?" one is really asking three questions: "What can go wrong?" "How likely is it?" and "What are the consequences?"
The first question, "What can go wrong?" is usually answered in the form of a
- scenario" (a combination of events that could occur) or a set of scenarios. Examples in the nuclear materials field include events causing early failure of the engineered barrier system in a waste repository or loss of a sealed source.
The second question, "How likely is it?" can be answered in terms of the available evidence and
. the processing of that evidence to quantify the uncertainties involved. In some situations, data may exist on the frequency of a particular type of occurrence or failure mode (e.g., actuarial data on losses of sealed swrces or accidental overexposure). In other situations, there may be little or no data and a Bayesian approach for analyzing uncertainties will be required.
The third question, "What are the consequences?" assesses, for each scenario, the probable range of outcomes (e.g.', radionuclides release rates or dose to the public) given the uncertainties. From this assessment, the important scenarios can be identifed. The outcomes or consequences are the "and states" of the analyses. The choice of consequences, that is, the measures of risk, can be whatever seems appropriate for reasonable decisionmaking in a particular regulated activity. The choice could involve combinations of end states or even non-safety consequences, such as technical feasibility, cost, and schedule (i.e., programmatic risk).
Traditional and Probabilistic Approaches
-The triplet definition of risk and risk assessment provides a clear framework for distinguishing between what many practitioners and regulators refer to as deterministic and probabilistic
' Kaplan, S., and B. J. Garrick, "On the Quantitative Definition of Risk," Risk Analysis, Vol.1, No.
1, March 1981.
3 analyses. The ACNW recommends that Sections 1 and 2 in the white paper be modified to incorporate the concepts discussed below, in particular, traditional deterministic safety analysis addresses only two of the three risk questions in an explicit manner (i.e., "What can go wrong?"
and "What are the consequences?"). Such questions have always been the building blocks of so-called deterministic safety analysis, even 5 arriving at the design-basis accident. Thus, safety analysis is seen to be a subset of risk ans!ysir,. k is not a matter of deterministic analysis l
versus probabilistic analysis, but more a question of expanding the scope of the analyses to include consideration of likelihood in a direct manner, in simple, well-understood systems, likelihood may be easy to establish with reliability, in more complex situations, such as a waste repository analysis, the definition of likelihood becomes the central challenge.
Risk Assessment and Defense in Depth The white paper discusses defense in depth (DID) in footnotes 1 and 4. The ACNW specifically endorses the Advisory Committee on Reactor Safeguards'(ACRS) recommendations to 2
modify footnote 1 and delete footnote 4. As currently drafted, footnote 4 does not recognize the difficulty in assessing the performance of multiple-barrier systems in the waste management licensing arena. The ACNW recommends that the DID concept be discussed in the main body of the paper with respect to the following issues. The white paper should make the point that a
- risk-informed' approach implies quantification of all elements of defense. Although the uncertainties of some elements of defense may be substantial, the fact that they have been identified can greatly aid in deciding how much defense makes regulatory sense.
The concept of DID has always been, and should continue to be, a fundamental tenet of regulatory practice in the nuclear field. In a risk-informed era, the opportunity exists to make DID transparent. In particular, the tools of probabilistic risk assessment (PRA) and performance assessment (PA) should be challenged to expose the capability of all elements of defense. Good decisions on the adequacy or the necessity of elements of defense can be made only through identification of the individual performance of each defense system in relation to overall performance. A clear display of the uncertainties associated with each defense system is essential. The connection between elements of defense and overall performance measures, including their individual uncertainties, allows implementation of the DID concept.'
Risk Based and Risk informed The Committee agrees in principle with the distinction made in Sections 4 and 5 of the white paper between risk based and risk infonned, whereby the former implies that decisions must be 8
Letter dated March 11,1998, from R. L. Seale, Chairman, ACRS, to Shirley Ann Jackson, Chairman, NRC,
Subject:
ACRS Comments on Draft Paper on Risk-informed, Performance-Based Regulation.
8 Letter dated October 31,1997, from B. John Garrick, Chairman, ACNW, to Shirley Ann Jackson, Chairman, NRC,
Subject:
Recommendations Regarding the implementation of the Defense-in-Depth Concept in the Revised 10 CFR Part 60.
4 l
based exclusively on risk assessment results, while the latter implies that decisions are based on risk in conjunction with other information. The Committee believes that a risk assessment is I
not a decision analysis, per se, and that risk-based approaches to decisionmaking must consider other factors, such as costs, benefits, and socio-political issues, in addition to risk.
The Committee does not agree, however, with the implication in the white paper that factors such as *the basis for current regulations, engineering analysis and judgment, and the defense-
. in-depth philosophy" are outside the boundaries of risk assessment. These factors affect the uncertainties of the risk measures - uncertainties that should be part of a complete risk assessment. There is nothing about the triplet definition of risk that implies that risk assessment cannot include these factors.
Performance Based Section 6 of the white paper titled " Performance-Based" needs to be rewntten to reflect a much broader use of the term in all NRC regulations. The current waste regulations, including 10 CFR Part 60, high-level waste (HLW); 10 CFR Part 61, low-level waste; and the decommissioning rule, contain performance objectives and criteria, which are generally based on calculated dose, as key regulatory requirements. These are performance-based approaches. The discussion in Section 6, pages 4-6 of the white paper, does not appear to recognize that dose-based approaches are fundamentally performance based.
The ACNW believes that one of the major differences between materials and reactor licensees occurs in the case of performance-based regulations. For example, the first and third attributes of performance-based regulations mentioned in the white paper failin the case of HLW regulations (10 CFR Part 60). The first attribute indicates that monitoring is essential, but the
- assessment of performance by monitoring of closed geological repositories is an unresolved issue. The third attribute might be taken to imply that subsystem requirements are a necessary part of the regulations. Such an interpretation runs counter to RIPBR.* The white paper does acknowledge these differences in footnote 4, but be:ause possible misinterpretation of the definition of " performance-based regulations" may create an ambiguity in the HLW licensing process, the definitions should be more explicitly stated.
Regulatory Burden The white paper, which discusses the issue of regulatory burden in Section 5 on page 4, should be augmented to address the following issue. The Committee is concemed that the spirit of the PRA Policy Statement is compromised if risk-informed continues to be interpreted (in the regulatory field) as in addition to, rather than as a substitute for outdated regulations. The Committee agrees that a careful transition to greater use of risk methods in regulatory decisionmaking is necessary. Although the PRA Policy Statement promises a reduced burden on licensees, the commitment by the NRC to address this issue is weak. What appears to be missing is a clear indication of how and when the regulatory relief implied in the PRA Policy
- See footnote 3
5 Statement will occur. The ACNW recognizes that the white paper is not the place to establish policy, but there is an opportunity to clarify this issue by addressing " reduction in licensee burden" explicitly in the paper.
Closing Comments This letter has discussed RIPBR primarily in relation to geological repositories and nuclear
~
waste isolation. Risk assessment is the essential bas.i, upon which the overall safety of a potential repository will be judged. While very different in detail, PRA of nuclear power plants and PA of geological repositories are similar in terms of system complexity and the application of probabilistic methods to the determination of safety. The PA experience base of Yucca Mountain and the Waste isolation Pi:ot Plant, together with the extensive PRA experience with nuclear power plands, provides a varied and extensive risk assessment landscape for considering the apptability of basic definitions and concepts. In simpler situations, the risk may be relatively well defined. Examining the definitions and concepts recommended in this letter against such a wide spectrum of applications gives the Committee high confidence in their applicability to all the nuclear materials regulated by the NRC. However, this conclusion presumes an extremely flexible framework for the implementation of RIPBR across the full spectrum of the materials, processes, and facilities regulated by the NRC. This is the underlying point of our recommendations. We believe such a framework is necessary and feasible. We appreciate the opportunity to offer our views on how to make the subject white paper serve this extremely important purpose.
Sincerely, B. John Garrick Chairman
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l ADVISORY COMMITTEE ON NUCLEAR WASTE g
WASHINGTON. D.C. 20666 i
s......
April 29.1998 The Honorable Shirley Ann Jackson Chairman U.S. Nuclear Regulatory Commission.
Washington, DC 20555-0001
SUBJECT:
COMMENTS AND RECOMMENDATIONS ON INTERIM GUIDANCE IN SUPPORT OF THE FINAL RULE ON RADIOLOGICAL CRITERIA FOR LICENSE TERMINATION
Dear Chairman Jackson:
During its 99th meeting on March 23-25. 1998, the ACNW heard and discussed a presentation by the Office of Nuclear Regulatory Research on NRC's final rule and regulatory guidance for demonstrating compliance with the radiological criteria for license termination.
The issue of license termination is complex because of the very broad spectrum of. licensees and sites. -In many cases, such as sealed-source sites, license termination is simple.
In other cases, license termination can b6 granted only with restrictions and financial guarantees.
In a few other cases, license termination may not be granted under any circumstances because of the magnitude or extent of contamination.
In the case of a simple license termination. there is no need to use dose-based models to demonstrate compliance with the final rule.
For the more, complex sites, it is appropriate to start the process of decommissioning using a dose-based screening model and to progress to a more detailed site-specific anal,ysis as necessary.
,In this letter, the ACNW has focused on the more complex sites requiring dose-based models. The much broader task of addressing the whole gamut of types of license terminations, especially those cases involving uranium and thorium, will-be addressed in a future letter.
l t___ _ _ n _
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To gain insight on the practical application of the new approach, the Committee supports the decision to introduce the new screening tool and decision methodology and to issue the documents immediately on an interim basis for 2 years. The Committee considers the new approach using the DandD computer code to be consistent with the trend toward introduction of a risk-informed, performance-based (RIPB) philosophy in essentially all NRC licensing.
The new approach allows licensees to use a simple generic approach for low-risk sites ~ or to use increasingly more realistic and site-specific analyses.
iteratively as needed, to demonstrate compliance. The licensee can assess the
. relative cost and benefits of continuing with additional data collection, or remediating specific' areas in order to achieve compliance.
Although the ACNW has not investigated all potential sources of conservatism in the new DandD code, we are persuaded that it is not inherently over-conservative as a screening tool.
Introduction of regional parameters rather than a single. set of national parameters could reduce conservatism. The 2-year trial period recommended above will allow these and similar concerns to be carefully evaluated.
. There are.several issues concerning the new approach in its current form that can and should be addressed.' In particular:
1.
The regulatory guidance documentation is formidable and likely to deter even the most motivated of licensees from using and gaining familiarity with it. The Committee urges that the staff repackage the guidance in a more user friendly, menu-driven electronic format that includes guidance to licensees on additional relevant NUREGs.
2.
The approach outlined in the guidance for implementing the as low as reasonably achievable (ALARA) requirement may lead to unnecessary conservatism when using the DandD screening model.
The Committee believes that if a licensee complies with the 25
. mrem dose criterion using the screening methodology, the licensee will have met the intended ALARA requirement.
(The dose calculated using site-specific analyses is expected to be lower in most cases).
3.
NRC should retain the flexibility to adjust the new DandD model if additional studies invalidate the linear no-threshold dose response hypothesis.
i
3 4.
Introduction of the new decontamination and decommissioning approach will require significant resources during the 2-year trial period for field testing, training, evaluation and guidance development.
In particular, the ACNW encourages NMSS to follow-through with its plans to test the DandD code on a complex site.
A strong commitment and adequate resources are needed if NRC is to move forward with RIPB regulation.
The problem of dual regulation, that is, by the Environmental Protection
- Agency and by NRC. was raised by representatives of the Nuclear Energy Institute during the meeting. This is a serious issue that needs to be resolved. The ACNW believes that by introducing the RIPB approach to license termination, the new methodology could assist in alleviating the conflicts associated with dual regulations as it should lead to more defensible and
. consistent regulatory decisions.
The ACNW plans to become more familiar with the DandD code and the license termination process during the next 2 years of testing and will keep the Comission informed of any significant developments.
Sincerely.
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UNITED STATES I
NUCLEAR REGULATORY COMMISSION a
ADVISORY COMMITTEE oN NUCLEAR WASTE WASHINGTON, D.C. 20006
. October 8,1997 l
The Honorable Shirley Ann Jackson Chairman U.S. Nuclear Regulatory Commission
' Washington, D.C. 20555-0001 Dear Chairman Jackson
SUBJECT:
Comments on Performance Assessment Capability in the NRC High-Level Radioactive Waste Program The purpose of this letter is to advise the Commission about the NRC staffs performance assessment (PA) capability in the High-Level Radioactive Waste (HLW) Program. Performance
, assessment is an important tool in NRC's relicensing activities,' including the following:
understandmg the importance of specific site charactenstics and the design of engineered features to the performance of an HLW repository at Yucca Mountain, prie
,g key technical issues (KTis) and staff activities, developing revised standards and regulations for licensing, and preparing for review of the Department of Energy's (DOE's) viability assessment (VA) of the proposed repository.
The evaluation of staff HLW PA capability continues to be a priority issue of the-Advisory Committee on Nuclear Waste (ACNW).
l The observations and comments in this letter have been developed, in part, on the basis of the 93rd ACNW Meetmg at the Center for Nuclear Waste Regulatory Analyses (hereafter the Center) '
l in San Antonio, Texas, on' July 23-24,1997. The ACNW previously reviewed and commented on staff HLW PA capability in letters dated December 2,1991, and May 27,1994.
Recommendations The Committee makes the following recommendations:
Selected capabilities should be added to the program to provide feither assurance that the I
1 staff has the ability to assess the containment capacity of the engineered systems. Support for KTis relating to the near-field performance of the repository should be restored Among the deciplines for which the ACNW believes added capability is necessary aie engineering analysis, materials science, and chemistry. The cr=?% discipine of corrosion science l
and engineering is also an essential part of the mix.
i The PA models should be structured to represent repository performance as realistically as possible and thereby provide the necessary information for regulators to make decisions in the context of the full state of knowledge about the performance measures of the t
repository. Improved coordination and communication between the NRC staff and the L
Center will be essential.
4
2 Greater emphasis should' be given to collecting, organizing, and documenting the supporting evidence for the performance assessments to enhance acceptance of the results. An important element of this is improvement in communicating the abstraction of process models into gdebilistic models. Of particular interest to the Committee is visibility of the treatment of such phenomena as chemical and geological processes leading to the mobilization of radionuclides in the near field.
A working version of the NRC'sIotal Performance Assessment code, version 3.1 (TPA-3) should be implemented as soon as practicable.
A program for verifying TPA-3 should be developed. TPA-3 should be benchmarked against other codes for Yucca Mountain. The Committee also encourages exposure of the methods of TPA-3 and associated background information to the scientific community through extensive and timely peer review.
Accompilahments The Committee commends the staff for its many impressive accomplishments in upgrading and preserving a dedicated HLW PA team in the face of budget cuts and programmatic uncertainties.
The organization of the HLW Program around a specific set of KTis and the grouping of expertise.
and disciplines within the KTis provides an important means of focusing the staff's efforts on issues-most important to performance of the repository. Performance assessment is important in the staffs efforts to provide integration across disciplines in the KTis and to set priorities for activities.
The Committee was pleased to see the clear integration of PA with other Yucca Mountain activities.
This effort has led to the development of sound, near-term plans for relicensing activities, including resolving outstanding issues and preparing for review of DOE's total system performance assessment supporting the viability assessment (TSPA-VA). The revised and updated TPA-3 code
. increases the staffs capability in performance assessment modeling. The code should facilitate the KTl investigations with its ability to evaluate the importance of specific site characteristics and the effectiveness of engineered bemors The ability to conduct sensitivity and uncertainty analyses for subsystems and for the total system is improved The development of the code is a solid effort and we encourage the staff to pursue aggressively the implementation of TPA-3. Many of these.
staff activities conform to recommendations contained in the ACNWletter of May 27,1994, on PA capability.~
Engineered Barrier System
- The ACNW is concemed about the staffs capability to evaluate quantitatively the engineered.
barrier system of the proposed Yucca Mountain repository. This concem is punctuated by lessons loamed from PA, including the apparently increasing dependence on engineered barriers to
' demonstrate compliance with a dose-or health-based standard for the repository. With increasing
. evidence that engineered systems must be an important part of the waste isolation strategy for Yucca Mountain, it is important that these systems receive extensive scientific and engineering scrutiny.-
, We are concemed about the decision to reduce the effort at the Center on certain KTis, most
L i
l 3
I notably those dealing with engineered barriers and radionuclides transport. The shifting emphasis of the DOE to the performance of engineered systems accents the need for the Commission to provde resources to restart work on the KTis most important to an independent assessment of the performance of engineered systems and near-field radionuclides transport. A concem is that without restarting the work of the NRC staff and the Center, the performance assessment effort, including the TPA-3 code, will not have the scope to assess adequately the DOE work. The Committee urges the Commission to act on this issue as soon as practicable.
Beyond the issue of the scope of the engineered systems assessment capability of the NRC staff, the ACNW believes that added capability is necessary to analyze adequately the engineering design of long-lived, passeve high-integrity systems. In particular, additional staff effort is required in engineering analysis, materials science, and chemistry (especially corrosion and colloid chemistry) to have the full capability to assess the engineered systems.
P--"-*te "e.t.w.ar.ca A -- =..cr.; E -M:
The ACNW has three primary points to make regarding the staffs performance assessment
-' modeling activities:.. (1) the pas should have a risk-informed perspective; (2) the pas should be transparent about the supporting evidence (data and information); and (3) the relationship between process model and probabilistic calculations needs to be made clear.
Risk-informed performance assessment provides the opportunity to assess realistically the performance of an HLW repository. Our concem is that the TPA-3 activity is relying too much on bounding and worst-case calculations. Although bounding calculations are a very useful part of i
any technical investigabon in providing insights on what is important to the performance measures of a model, such calculations are often oflittle value in representing what is likely to happen. In the opinion of the ACNW a much preferred approach is to limit bounding and worst-case calculations to the task of scoping the investigation and deciding what may or may not be important to model.
Decision making requires more information. The decision-maker needs to know the total range of uncertainty of the pede.T.,ance measures. The primary tool for communicating uncertainty, rather than just an upper bound, for example, is to embed the performance measures in probability distributions so that the full range of values and all their supporting evidence are visible. For example, if the value preferred by the regulator is the 90th percentile value, then it is explicitly clear l
Just how conservative the regulator has chosen to be.
1 The Committee stresses the importance that the evidence (i.e., data and all other information) that
' is the basis of the PA model be clearty visible, particularly regarding the abstraction from physical process models to probabilistic calculations. - We are especially concemed with the abstraction of informaton about the engineered systems, especially under the circumstances of not having a fixed desgn. In addition, supporting evidence for modeling important phenomena such as the chemistry l
of redox reactons is weak. Our current impress' n is that more attention is being given to methods e
than to the required information to support those methods.
Analysis Capability The ACNW was impressed with the progress in the development of NRC's TPA-3 code. We are anxious to follow the development of TPA-3 and look forward to more discussions with the staff.
E_ _ __.____-____ _ - - - - - - - -
4 The ACNW urges the staff to implement a working codu in an expeditious manner so that the code is fully functional as the TSPA-VA analyses are made available to NRC.
The Commission has indicated an interest in moving toward a risk-informed, performance-based philosophy of regulation. Of concem to us is whether the TPA-3 effort is keeping pace with the c
development of methods and ideas on how to implement such a philosophy.
An issue with TPA-3 is how to venfy the code. The problem as stated by the staff is that because the code is designed speedcally for the Yucca Mountain site, intomational bench marking is almost impossible. It is true that parts of the code, such as NEFTRAN (Network Elow and IRANsport),
have been benchmarked. The NRC staff must see that TPA-3 is benchmarked against applications of other codes to Yucca Mountain. The ACNW also believes that the NRC staff should pursue other avenues of peer criticism of its codes, such as publication in refereed engineering and scientificjoumals.
Although the ACNW believes that it is important to develop a PC compatible version of the code to reach more users, we would not like to see other important activities compromised to reach this goal. ' A PC compatible version should not be created at the risk of oversimplification. Meanwhile, to conduct a full range of analyses in reviewing DOE's TSPA-VA, the staff requires the NMSS Advanced Computer System or a suitable attemative.
We believe that these comments provide constructive guidance on the future direction of the performance assessment effort and look forward to following NRC staff progress in this important activity.
(K, Sincerely, D
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B. John Garrick Chairman
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NUCLEAR REGULATORY COMMISSION i
7,,
E ADVISORY COMMITTEE ON NUCLEAR WASTE C,
WASHINGTON, D.C,20555 I
March 6, 1998 The Honorable Shirley Ann Jackson Chairman U.S. Nuclear Regulatory Commission Washington. DC 20555-0001
Dear Chairman Jackson:
SUBJECT:
ACNW'S SUPPORT FOR THE NRC STAFF'S APPROACH TO ASSESSING THE PERFORMANCE OF MULTIPLE BARRIERS
' During its 98th meeting on February 24-26, 1998, the Advisory Committee on Nuclear Waste (ACNW) heard a briefing on, and discussed with the NRC staff.
SECY-97-300. " Proposed Strategy for Development of Regulations Governing Disposal of High-Level Radioactive Wastes in a Proposed Repository at Yucca Mountain. Nevada." In our previous letter of October 31. 1997
" Recommendations Regarding the Implementation of the Defense-in-Depth Concept in the Revised 10 CFR Part 60." the. Committee recommended, among other matters, abolishing subsystem requirements in the planned. revision to 10 CFR Part 60 and instead requiring quantification of the performance of individual barriers. The purpose of this letter is to reiterate this position and to express our support for the direction the NRC staff is taking in its proposed strategy on the subject of subsystem requirements.
The basis for our recommendation was that improved information and methods of analysis, together with a determination of the risk of an appropriately defined critical group, allowed for a more direct and reliable assessment of Yucca Mountain performance than would be derived from prescribing the performance of repository subsystems.
Important to our position on this approach is the requirement that, in addition to calculating the risk to the critical group, there should be the requirement that individual barriers be assessed quantitatively for their contribution. The key difference between the two approaches is quantifying subsystems to reveal their contribution to overall performance versus prescribing the performance of subsystems I
regardless 'of their contribution to overall performance. The Committee believes that the former approach provides assurance on just how effective I
2 individual systems are in achieving an overall performance requirement while preserving.the need for f_lexibility to achieve an optimum or a near-optimum design.
Finally, the approach is believed to be~ an excellent example of a risk-informed ana1ysis.
The staff indicated that it plans to require a system of multiple barriers l
without specifying quantitative requirements for individual barrier l
performance. Further, the staff plans to require DOE to demonstrate the contribution of individual barriers and their respective uncertainties to total systems performance by providing results of intermediate calculations within the performance assessment. The staff believes that this transparency in analyses will provide insights about the key contributors to system-level performance needed to support licensing decisions.
Finally, the staff indicated that possible approaches to demonstrate individual barrier contributions and uncertainties may include the use of sensitivity analyses.
scatter plots, and importance analyses.
Factors increasing confidence in a risk-informed approach to assessing subsystems, as well as total system performance measures. include: (1) over 20 years of experience in the application of probabilistic risk assessment to nuclear reactors and other systems: (2) some 15 years of experience in conducting performance assessments. especially in regard to the proposed Waste Isolation Pilot Plant and Yucca Mountain repositories; and (3) the growing amount of site-specific information obtained through the site characterization process. A key feature of the improvements in analysis is in the area of quantifying uncertainties of key parameters and models.
Exposing the uncertainties associated with performance, especially the performance of subsystems, adds new meaning to the concept of multiple barriers.
In one sense, knowing the uncertainties is a step toward quantifying the multiple
' barrier approach and providing insight on just how much safety margin actually exists.
The ACNW commends the staff for proposing to require 'quantification of multiple barrier performance in favor of quantitative subsystem requirements and considers the approach to exemplify a true risk-informed analysis. To implement such an approach the ACNW articulated two primary needs-in a letter dated _0cotber 31,1997. " Application of Probabilistic Risk Assessment Methods to Performance Assessment in the NRC High-Level Waste Program." One is that performance assessments should, to the extent practicable, be developed using realistic models with uncertainties included. The Committee has also recommended that : methodology be developed, using an event tree or similar type of approach. that presents performance assessment modeling.results in a way that clearly indicates the rank-ordered contributors to total system
3 performance (e.g.. dose) and to evaluate the performance of different subsystem components..The ACNW continues to encourage the staff to explore use.of a post-processing methodology that enables rank-ordering of contributors to total system performance in demonstrating individual barrier performance.
Sincerely.
M
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B.
John Garrick Chairman i\\
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t 8
NUCLEAR REGULATORY COMMISSION e
' ' 4 r
ADVISORY COMMITTEE ON NUCLEA2 WASTE j.
g WASHINGTON, D.C. 20556 l
December 23, 1997 l
. The Honorable Shirley Ann Jackson
- Chairman-U.S. Nuclear Regulatory Commission Washington D.C. 20555-0001 1
Dear Chairman Jackson:
SUBJECT:
1998 STRATEGIC. PLAN AND PRIORITY ISSUES FOR THE ADVISORY
' COMMITTEE ON NUCLEAR' WASTE l
The Advisory Committee on Nuclear Waste (ACNW) has developed a Strategic Plan that includes priority issues it'will consider in 1998. A copy of the plan is attached for your consideration. The ACNW's Strategic Plan is anchored to.the NRC's. Strategic Plan, and supports the NRC mission, vision. and select goals.
strategies and substrategies relevant to NRC's responsit'lities for management and oversight of commercial _ nuclear waste and materials. The ACNW's Strategic
~
Plan also interfaces with the ACNW Operating Plan, which is being updated to reflect the priority issues identified herein.
One purpose of the ACNW Strategic Plan'.is to guide the Committee in carrying out its mission over the next year. A highlight of the plan is identification of the Committee's_ near-term priority issues for this year, and longer-term issues for times beyond one year. The ACNW does not plan to focus to any.
great extent on most of the longer-term' issues this year due to resource constraints and timeliness of these issues, unless directed to do so by the Commission.:
In. addition to priority technical issues, activities related to ACNW operational processes that we plan to initiate this year to improve our efficiency:and effectiveness are identified.
We would appreciate any coments.or suggestions from the Commission.
i Sincerely, h
'h t
B.' John Garrick Chairman i'
Attachment:
As stated l'.
___1_i__.____________.___._.
i J
ACNW 1998 STRATEGIC PLAN AND PRIORITY ISSUES AND ACTlVITIES i'
l This plan provides strategic direction to the ACNW in 1998 and beyond for focusing on issues most important to the NRC in carrying out its mission of protecting public health and_ safety, promoting the comon defense and l
security, and protecting the environment.
It also communicates ACNW's mission, vision goals, and priority activities and shows how these goals L
support the NRC's Strategic Plan.
i SCOPE OF ACNW ACTIVITIES The ACNW provides advice on issues concerning the storage ar.d disposal of high-and low-level radioactive waste (HLW and LLW. respectively), including the interim storage of spent nuclear fuel, materials safety and decommissioning, and other issues as requested by the Commission.
j l
ACNW MISSION The ACNW's mission is to provide independent and timely technical advice on nuclear waste management issues to support _ the.NRC in its conduct of an t
efficient regulatory program that enables the Nation to use nuclear materials in a safe manner for civilian purposes.
r ACNW VISION. DESIRED OUTCOMES. AND COMMITMENTS Vision The ACNW strives-to provide advice and recommend solutions that are forward-
'looking are based upon best-available science and technology, can be l
implemented, and reflect the need to balance risk, benefit, and cost to i
society to enable the safe use of nuclear materials.
Desired Outcomes The ACNW strives to:
i 1.
provide technically sound and timely advice that can be incorporated into NRC technical approaches, documents, and regulations:
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>2.
provide advice that reflects state-of-the-art science and technology that can be readily incorporated into NRC regulatory practices:
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L 2-3; comunicate its message clearly and concisely to its intended audience:
4.
be respected by the Commission. NRC staff.. EPA. DOE. and the public and be perceived as adding value:
5.
be trusted by the public to provide frank, open advice, and offer a forum for public participation in the regulatory process, thereby making the regulatory decisionmaking process more transparent to the public:
6.
assist in resolving conflicts between NRC and DOE. EPA, and other stakeholder by providing a forum for interaction, and by continually encouraging communication between and among these entities; and 7.
operate in a spirit of openness as intended by the Federal Advisory Committee Act (FACA) and the Government in the Sunshine Act.
Commitments The Committee makes the following commitments in pursuit of its vision:
1.
be responsive to the Commission's needs:
2.
remain flexible, be responsive to change, and consider various options and contingencies:
3.
foster an atmosphere of mutual problem-solving with the NRC-staff:
4.
challenge the status quo, as appropriate, thereby becoming an " engine for change":
5.
identify in advance those issues that could have an impact on NRC's ability to achieve its mission:
6.
focus on risk, by asking. "what is the risk, what are the contributors to risk. and what are the uncertainties?";
7.
keep abreast of international trends and developments that could influence NRC policies or approaches:
8.
maintain technical excellence and independence:
9.
' operate in a cost-ef.fective and efficient manner: and
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- 10. ' measure the Comittee's effectiveness.
f GOALS AND OBJECTIVES The ACNW has developed general goals and objectives consistent with its.
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mission.and ' vision. The five. goals listed below serve to provide strategic direction for the ACNW this year and support select goals, strategies, and g
- substrategies identified in NRC's Strategic Plan.
For each goal, objectives that help us to focus on our priority issues are identified.
Goal'1:
Assist the NRC in positioning itself to respond to external change and uncertainty in the management of nuclear waste.
l This goal supports the RC mission, vision, and select strategies or substrategies under NRC Goals 2 through 7.
- Objective 1:
Advise the Comission in a timely fashion on issues of a technical nature that may require changes in the regulations.
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-lbjective-2:
Inform the Cmmission about issues that could cause problems for the NRC or society if not given ' adequate attention, and recomend solutions.
Goal'2:-
Strive to ensure that NRC'1s' employing the best science-in resolving key safety issues.. This goal supports the NRC
. mission, vision, and select strategies or'substrategies.under NRC Goals 2 through 7.
j Objective 1:
Keep abreast of cutting-edge methods and technologies being_
. developed and utilized world-wide that are applicable for assessing and managing risks associated with cleanup; disposal.
- and storage of nuclear waste.
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lbjective 2:
Advise the Comission on projected or perceived technical shortcomings in NRC staff capabilities that could adversely inpact the agency's ability to address safety 1ssues.
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lu L__.____~____-__._____
_m_._.___.._..
_ _. _ _ _ _.._..m.______
___.___._.m.
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4 Goal 3:
Advice the NRC on how to increase its reliance on risk as a basis for decisionmaking, including using risk assessment methods for waste management, that (1) implement a risk-informed approach, (2) are consistent across programs where possible, and (3) quantify and reveal uncertainties. This goal supports the NRC mission, vision, and select strategies and substrategies under NRC Goals 2 through 7.
Objective 1:
Propose approaches and encourage the staff to gain a better understanding of the inherent risks of licensed activities in nuclear waste and materials, and the relationship between regulations. cost, and safety.
Objective 2:
Examine risk-assessment approaches being utilized within the NRC's waste and materials programs and reconmend improvements for making more transparent the underlying asswptions and associated uncertainties incorporating greater realism where appropriate, and identifying apparent inconsistencies in approach.
Goal 4:
Support the NRC in improving public involvement in its waste programs and gaining increased public confidence and respect.
This goal supports the NRC mission, vision, and select strategies or substrategies under NRC-Goal 6.
Objective 1:
Provide opportunities through the FACA process for more public involvement in the regulatory process.
Objective 2:
'Reconmend ways for the NRC to gain more meaningful public involvement in the regulatory process.
' Objective 3:
Assist the NRC in making more transparent the agency's decisionrnaking process and ensuring agency docurnentation is thorough clear, and readily understandable.
Goal 5:
Improve the effectiveness and efficiency of ACNW operations.
This goal supports the NRC mission, vision, and select strategies or substrategies under NRC Goal 7.
Objective 1:
Increase the value of ACNW advice to the Cwmission and staff.
Objective 2:
Inprove and modify existing operational procedures to accortplish more with less. **
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PRIORITY ISSUES AND PROCESS IMPROVEMENTS In support of its first.four goals, the.ACNW has identified priority issues for this year, and longe. -term issues it plans to address in the future, given
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sufficient resources. Also identified are the criteria the Committee uses to select its priority issues.
In support of its fifth goal the ACNW has identified priority process-related activities it plans to carry out this year to improve its effectiveness.
The priority issues identified for 1998 are considered first-tier priorities, and the longer-term issues are considered second-tier ACNW priorities. The Committee does not plan to focus to any great extent on second-tier issues this year' unless directed by the Comission. or dictated by external events.
such as changes in nuclear waste legislation.
Each priority issue supports one or more of ACNW's goals. as indicated.
For each first-tier priority issue, the Committee plans to prepare a task action plan that identifies the nature and scope of the issue and a strategy for addressing it, including planned product [s] and schedule, and performance measures and targets that will enable the Committee to determine if it has achieved its goals.
CRITERIA FOR SELECTING PRIORITY ISSUES i
the protection of the public health, workers. and the environment from adverse effects of the management of nuclear waste, especially in regard to disposal facilities. i.e., the risk significance of an issue:
issues that arise from strategies and activities of licensees and applicants:
timeliness based on when an issue is scheduled to come before the Commission. and when the' advice would be of greatest benefit to influence the Commission's regulatory decisions:
the relationship of an issue to the NRC's Strategic Plan, including trends and directions in regulatory practice, such as the adoption of a risk-informed, performance-based method of regulation and decisionmaking:
the potential for or likelihood of an issue to pose undue risk or costs to society:
i u.________.___________
n 6-issues that are requested for ACNW review by the Commission or Commissioners: and ^
- issues that arise based on the scientific and technical basis of
- information supporting the safety and performance assessments of nuclear
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waste disposal. facilities. including the quality and level of expertise
- involved.
FIRST TIER PRIORITY ISSUES Viability Assessment and Site Characterization - The DOE is scheduled to complete its Viability Assessment-(VA) by September 1998. The NRC staff
. anticipates receiving' draft VA products before then, and submitting a Commission paper on its. review of the VA in November 1998.
In addition..the staff is developing Issue Resolution Status Reports.(IRSRs) that document the status of;and acceptance criteria for each Key Technical Issue (KTI) to support its review of the VA and License Application (LA) as well as.a VA Review Plan. The ' staff's review of the VA will be a preliminary review of the eventual LA,.and is ' expected to provide valuable insights. The ACNW plans to review DOE's conclusions and the NRC staff's review of the VA, as well as monitor the IRSRs. The ACNW also anticipates tracking the evolution.of DOE's.
Tsite characterization program and the DOE's waste isolation and containment strategy. This. issue supports ACNW Goals 2.and 3.
Risk-Informed Performance-Based Reaulation - The ACNW will continue to support the agency's effort to move from deterministic. regulations toward risk-informed and performance-based regulation. The. Committee anticipates continuing to encourage the NRC'to adopt regulatory approaches.that are
- comprehensible and enhance public understanding of:the key safety issues, and continuing to encourage the NRC to use risk.as a basis for setting priorities.
Issues to be addressed under this topic include the following: HLW regulatory.
framework issues, including NRC staff's strategy to revise 10 CFR Part.60:
- NRC's comments on'the proposed EPA HLW standard (40 CFR 197)
- NRC's review of DOE's proposed Siting Guidelines in 10 CFR Part %0: performance assessment.
- including l continued monitoring of NRC's iterative performance assessments using the TPA code
- problems associated with dual regulatory authority between EPA'and NRC: and the evolving issues related to the use of expert judgment.
This issue. supports l ACW Goals 1 through 4.
.Enaineered Barrier System (FRS) - The ACNW will focus on the role of the EBS in the proposed repository, various components of the EBS and their
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significance to performance, and the NRC's capability to evaluate EBS performance.
A major focus will be on processes affecting waste package degradation and radionuclides release, including redox. reactions, corrosion.
radiolysis, microbiological effects, and reactions with introduced materials (e.g., concrete iron). Also included will be the models and methods used to predict long-term degradation of waste packages over time and the appropriate use of bounding models. This effort will likely include examining the use of i
coupled models.to predict the near-field environment and its impact on l
containment, release, and transport of radionuclides. This issue supports ACNW Goals 1 through 3.
Decommissioning - The ACNW has a strong interest in waste disposal issues-related to decommissioning.
In the past, the ACNW has advised the Comission on streamlining the Site Decommissioning Management Program (SDMP). aspects of the Proposed and Final Rule on Radiological Criteria for License Termination, and lessons learned from decommissioning the Pathfinder site.
The ACNW expects to review supporting guidance documents due in early 1998 for implementing the Final Decommissioning Rule, dose models and parameter selection criteria for decommissioning assessments, application of the LLW Performance Assessment Methodology to SDMP sites, and development of a mi ' ti-agency-sponsored decision support system to support decommissioning.
,.lso -
of interest is the issue of incidental wastes at DOE facilities.
Other activities may include tracking staff efforts to assess inherent risks of decommissioning and activities to simplify the decommissioning process, and assisting the Commission in contingency planning for a possible rapid increase in plant decommissioning due to deregulation. This issue supports ACNW Goals 1 through 3.-
Research - The ACNW will examine waste-related research and technical assistance programs in the NRC.
It will provide input to an ACRS report to Congress by February 1998, and a report to the Commission by June 1998. The ACNW will continue to monitor the NRC's research program to ensure that it is changing in response to the agency's shifting emphasis to risk-informed.
_ performance-based regulation. This effort will include assuring that research is focused on helping to assess the relationship between regulations and safety, and understanding the inherent risks of licensed activities. This issue supports ACNW Goals I through 4.
As part of the priority technical issues described above, the Comittee may focus on several initiatives throughout this year and beyond that would apply to some or all of these issues, such as international activities and seeking ways to improve public participation in NRC waste programs.
International activities may include participating in technical exchanges with other L__ ___
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l nations' regulatory waste programs or advisory panels.
With respect to improved public participation, the Committee may explore ways to encourage the public to participate in ACNW meetings.
If resources and time permit, the ACNW may also review lessons learned from other countries, other waste programs in the U.S., and directly from the public on ways to involve the public more meaningfully in NRC regulatory programs.
An example may be to encourage the public to participate formally in the performance assessment process. These issues support ACNW Goals 2 through 4.
~SECOND TIER PRIORITIES Renositorv Desion/ Thermal /Counled Processes - The ACNW will continue to focus its attention on the HLW repository design, including thermal testing and results and the significance of coupled effects on the performance of the proposed repository.
The ACNW will evaluate the adequacy of models to predict repository behavior.
For example, retrievability would be considered under this topic.
In addition. the issue of performance confirmation. including the type and quantity of data to be collected during this phase, will be explored.
This issue supports ACNW Goals 1 through 3.
Interim Storace Facilities for Soent Fuel The ACNW will begin to identify issues that the NRC may need to consider and prepare for in the event that proposed legislation is enacted to create a central.. interim HLW storage facility. This issue supports ACNW Goals 1 through 3.
DOE Oversicht - The ACNW will review waste-related activities associated with NRC's possible regulation of certain DOE facilities, if NRC assumes responsibility for those activities as a result of privatization or enactment of new legislation. This issue supports ACW Goals 2 through 4.
LLW and Aareement States Proaram - The ACNW will examine the role of the NRC in LLW disposal from the perspective that current trends in the national program may ultimately interfere with society's benefiting from the use of nuclear material. The ACNW will advise the NRC on alternatives to the current national LLW disposal program. The ACNW also may examine interactions between NRC and Agreement and non'-Agreement States, and whether communications can be improved. This issue supports ACNW Goals 1 and 4.
Radiation Risk Levels for Low-Level Ionizina Radiation - The ACNW will continue to examine the issue of radiation risk levels for low-level ionizing radiation. The ACNW may consider the question of what research, if any, the NRC should sponsor regarding the linear no-threshold (LNT) hypothesis, and the L
e appropriate regulatory approach, given the uncertainty about the LNT hypothesis. This issue supports ACNW Goals 1 through 4.
l Control and Accountability of Radioactive Devices - The-ACNW will examine the NRC's role in this issue, and whether, from a risk perspective. the NRC should initiate a rulemaking or take on a more aggressive role. This issue supports ACNW Goals 1 and 3.
PRIORITY OPERATIONAL ACTIVITIES Operational. process'es or activities that the ACNW plans to implement this year in support of ACNW Goal 5. " Enhance the effectiveness and efficiency of ACNW operations." is discussed below.
Strateoic Plannino - On an annual basis. the ACNW will conduct a top-down planning meeting to identify primary goals and priority issues and activities.
followed by a self-assessment to measure performance against these goals.
The ACNW will establish performance goals and indicators to measure effectiveness, j
and will use such tools as customer surveys to solicit feedback from the public on the Committee's effectiveness.
Imolement Chances in Operational Procedures - To improve its efficiency and effectiveness, the ACNW will improve its current processes for the following activities:
letter writing. ' scope and duration of meetings. interactions with Commissioners and the program offices, use of ACNW staff and consultants.
Improvements may include:
ensure letters are concise and consistent:
allow more time for strategic planning and agenda planning during meetings:
seek more opportunities to collaborate with ACRS to explore issues of common interest:
spend more time meeting individually with Commissioners:
increase the number of interactions with Program Office Directors:
use consultants to expand expertise:
)
encourage ACNW staff to initiate special projects and make presentations to the Committee:
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k 10 foster. an atmosphere of mutual problem solving with the staff:
consider options for gaining earlier access to predecisional material to l
assist the Coinmittee in providing more timely advice: and better define' and limit the number of priority topics.
UPDATING THIS PLAN The ACNW will. conduct a strategic planning meeting at least once a year, and will update this plan as needed. Revisions to the plan may be based on input from the Commission, changes made to the NRC Strategic Plan or Annual Performance Plan, results from customer surveys and self-assessments, extern-1 events and factors and available resources.
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UNITED STATES 8
NUCLEAR REGULATORY COMMISSION j
r,
.3 ADVISO5Y COMMITTEE ON NUCLEAR WASTE t,
WASHINGTON, D.C. 20E86 March 26,1998 The Honorable Shirley Ann Jackson Chairman l
U.S. Nuclear Regulatory Commission
(.
W
. ashington. D.C. 20555 0001
Dear Chairman Jackson:
SUBJECT:
- COMMISSION COMMENTS ON THE ACW STRATEGIC PLAN AND PRIORITY ISSUES This letter responds to your. letter of March 16, 1998. in which you provided the comments of the Commission on the Strategic Plan and Priority Issues of the Advisory Committee on Nuclear Waste (ACNW). We appreciate the Commission's review and
- comments. The Commission's view on our planned activities is very important because our primary mission is to provide the Commission with timely and useful advice.
-We will modify our Strategic Plan to reflect all objectives, the scope, and duties
- outlined in the ACNW Charter, as noted in your letter. The Committee will review our Charter in the near future, as required by statute, to assess the need to revise
.it consistent with the Commission's current views on ACNW activities..0ur Operating L
Plan is' consistent with the comments provided in your letter. Your comments on the-use of the Strategic Plan terminology are useful, and we will, in the future. revise the terminology so as not to be confused with agency requirements under the Government Performance and Results Act.
The ACNW will attempt.to accommodate as many of the suggested review areas (i.e..
Trojan waste classification, issues surrounding Envirocare and generic criticality
)
issues at low level waste (LLW) sites.. and setting appropriate standards for clearance levels. of asterials)' as practical in our future activities. ' The Committee l
is very much interested in being responsive to the Commission's needs and direction:
however. 'we are' limited in the number of review activities we can undertake and will have to communicate with you further on the actual resources needed to be fully
.i responsive to your comments on LLW and other. issues. We appreciate your thoughtful t'
and useful comments on our Strategic Plan and Priority Issues.
j Sincerely.
4 hon-
- 8. John Garrick l
Chairman i
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,