110th ACNW Meeting U.S. Nuclear Regulatory Commission, June 30, 1999
UNITED STATES OF AMERICA
NUCLEAR REGULATORY COMMISSION
ADVISORY COMMITTEE ON NUCLEAR WASTE
MEETING: 110TH ADVISORY COMMITTEE ON
NUCLEAR WASTE (ACNW)
Southwest Research Center
6220 Culebra Road
San Antonio, Texas
Wednesday, June 30, 1999
The Committee met, pursuant to notice, at 8:30 a.m.
B. JOHN GARRICK, ACNW Chairman
GEORGE HORNBERGER, ACNW Vice Chairman
RAYMOND WYMER, ACNW Member
CHARLES FAIRHURST, ACNW Member. P R O C E E D I N G S
MR. GARRICK: Good morning. The meeting will now come to
order. This is the third day of the 110th meeting of the Advisory
Committee on Nuclear Waste.
This entire meeting will be open to the public. Today the
committee will first review the staff's plans for conducting a review of
the Department of Energy's draft environmental impact statement for the
proposed repository at Yucca Mountain.
We will hear the NRC staff and the center discuss the
current concept of defense-in-depth as it applies to a high level waste
repository. And for the information of those in the audience, it is
intended to adjourn the meeting no later than noon.
During the afternoon, members will hold a one-on-one
individual technical discussion with the pertinent center staff on
selected areas of member interest.
Howard Larson is the Designated Federal Official for the
initial portion of today's meeting. This meeting is being conducted in
accordance with the provisions of the Federal Advisory Committee Act.
We have received no written statements or requests to make oral
statements from members of the public regarding today's session and
should anyone wish to do so, please make your wishes known to one of the
It is requested that each speaker use one of the
microphones, identify himself or herself, and speak with sufficient
clarity and volume so that he or she can be readily heard.
Our first topic this morning, as indicated, is the DEIS
review guidance and the committee member that will assist in leading
that discussion will be Charles Fairhurst, and, as I understand it, Mike
Lee is going to make the initial presentation.
MR. LEE: For the record, my name is Mike Lee. I'm in the
Division of Waste Management and I'm here to talk about the status of
the proposed plans for the review of the draft environmental impact
Just a few opening remarks, if I may. I just want to remind
everyone that we're focusing on the review of the draft. The adoption
of the final environmental impact statement is another issue and
involves a different set of plans and assumptions, which we haven't
prepared or developed at this time. So we're just focusing today on
this briefing of the review of the draft.
I'd also like to point out that we're also beginning to
enter a change in culture here. The last several years, we've been
focusing our program on key technical issues and at the receipt of the
draft environmental impact statement, we're moving into a different
frame of activity.
It's certainly pre-licensing, but it's more pre-licensing
than in the past. So when we review the draft, we're going to be --
draft EIS, we're going to be not abandoning the KTI approach, but we're
going to have a focused evaluation of issues related to performance and
Slide two is the outline for today's presentation, and I
have a rather short presentation. So I don't know, if you have
questions, do you want to interrupt me or do you want to just run
through the presentation and ask questions? How would you like to do
MR. GARRICK: Well, we don't know. We'll play it by ear.
We may interrupt you.
MR. LEE: All right. That's fine. If I could move to slide
three, then, please.
The program direction for how NRC is to conduct itself, as
well as other DOE and other agencies, as defined by the Nuclear Waste
Policy Act, as amended, NWPA directs DOE to issue a draft EIS for
comment and with respect to that EIS, NRC comments are to accompany any
DOE site recommendation.
I'd like to remind everyone that the Yucca Mountain site is
still under characterization. It has not been selected for development
as a repository. It's only being characterized at this time.
Should DOE decide to propose that Yucca Mountain be suitable
for development as a repository, it will submit a recommendation to the
President, along with NRC, along with the final EIS, as well as NRC's
comments on the draft EIS.
NRC's requirements for its part, which are intended to
implement the Nuclear Waste Policy Act, as amended, require that in any
potential license application for a geologic repository, that the
license application consist of general information, a safety analysis
report, as well as a final environmental impact statement.
And the Act also stipulates that in reaching any potential
construction authorization decision to build and operate a geologic
repository, NRC shall adopt DOE's EIS, to the extent practical.
Slide four, please. With respect to the respective roles of
NRC and DOE, the Nuclear Waste Policy Act, as amended, defines those
roles. For its part, DOE has the primary responsibility for evaluating
any potential environmental impacts.
The Nuclear Waste Policy Act also stipulates that DOE's EIS
is not required to consider the need for a repository, alternatives to
geologic disposal, or alternatives to the Yucca Mountain site.
For its part, NRC is a commenting agency with respect to the
draft EIS. CEQ regulations define lead agency and cooperating agency,
but not commenting agency. That's done by the Nuclear Waste Policy Act.
And NRC, in its commenting role, is expected to provide comments with
respect to the environmental impacts found within its jurisdiction or
areas of special expertise, and a background in what NRC's role is in
the review of the draft EIS can be found in the statement of
considerations for Part 51, both draft and final, as well as a number of
other Commission papers that have been written in the past.
If the committee needs reference to those Commission papers,
I'd be happy to provide those numbers off-line.
MR. GARRICK: Mike, can you just --
MR. LEE: Slide five talks about --
MR. GARRICK: Mike?
MR. LEE: Yes.
MR. GARRICK: Could you just highlight a few examples of
jurisdiction and special expertise in terms of -- give us some heads-up
on what the nature of the comments might be and the direction they'll be
headed for? I don't mean for you to try to talk about any results,
because you have no basis for doing that, but can you amplify that a
MR. LEE: On slide five, I was going to do that.
MR. GARRICK: I didn't see it. I looked ahead at five, and
that didn't tell me much, and that's why I asked the question. But go
MR. LEE: Okay. Well, why don't we just cut to the chase.
The second bullet on slide five says that NRC is going to review and
comment on the draft EIS. And what do we think the scope of our review
would include? At a minimum, we're going to focus on radiological
health and safety issues, both post-closure as well as pre-closure.
We're also going to review and examine transportation issues
off-site and we're also intending to review any other issues that may
have a bearing on the judicial review that would take place when DOE's
EIS goes final.
So the short version is we expect to do a thorough and
comprehensive review of the EIS, to the extent we can, during the 90-day
public comment period.
MR. HORNBERGER: Do you have any examples of what some of
these other issues might be?
MR. LEE: I know that doves and bunnies is surely one.
That's jargon for fora and fauna, things like that. But I guess to be
more precise, we'll be evaluating the impacts to the existing
environment. We'll be looking at issues related to the environmental
consequences of construction, operation and closure, including
short-term impacts of those activities.
We'll be looking at environmental equity issues. We'll be
looking at DOE's proposed mitigation plans for any potential
environmental impacts. We'll be looking at alternative designs which
DOE intends on including in the EIS, we understand, under three
different thermal loading regimes. We'll be looking at archeological
impact, cultural impacts, socioeconomic impacts, cumulative impacts.
How's that for a start?
MR. HORNBERGER: That's pretty comprehensive. But does NRC
have areas of special expertise in things like counting bunnies and
MR. GARRICK: I think they cut out.
MS. WASTLER: Are you there now?
MR. HORNBERGER: Yes. Did you hear the question or no?
MR. LEE: Dr. Hornberger, you broke up at the time you were
beginning to speak.
MR. HORNBERGER: My question was whether NRC had capability,
special areas of expertise in some of the areas that you mentioned; for
example, ecology or economics.
MR. LEE: Yes and no. As part of the development of our
review plan, a review group has been assembled. That will consist of
NRC staff, both in the Division of Waste Management, as well as the
Spent Fuel Project Office. In those areas for which we don't have the
right expertise, for example, in the areas that you just referenced, we
are going to rely on our contractor at the center or any subcontractor
that the center can line up to help compliment that review capability.
It's envisioned that we're going to have all the right
analytical or evaluative capabilities in place. We're not going to have
a lot of depth in those capabilities, but nonetheless, we hope to have
enough of the right type of staff that we could look at all the areas of
MR. GARRICK: Mike, could you also comment a little bit on
the tools you're going to use to address the health and safety issues?
Is the integrated safety analysis going to be a part of this?
MR. LEE: Well, I believe, for the post-closure performance
assessment or for the evaluation of post-closure and post-closure
impacts, we're going to rely on our ITA capability currently in place.
That was recently exercised for the staff's review of the VA.
For the pre-closure, we expect to use some capability that
has yet to be defined. It's not clear to me if we're going to have the
ISA in place in the next 30 days, because that's the current schedule
for the receipt of the EIS. But nonetheless, NRC has, in the past, had
extensive experience in the review of pre-closure safety issues with
regard to nuclear facilities. So whatever capability was available to
the staff in the past is certainly available at this time.
MR. FAIRHURST: Could I ask a question?
MR. GARRICK: Yes.
MR. FAIRHURST: Some of these issues, of course,
radiological impacts and so on are very long time periods. A typical
environmental impact statement does not deal with these kind of
MR. CAMPBELL: You'll have to repeat the question.
MR. FAIRHURST: Sorry. Are we back?
MR. CAMPBELL: Try repeating the question.
MS. WASTLER: San Antonio, could you repeat the question,
MR. FAIRHURST: Yes, I will. I was asking that, for
example, in your integrated safety assessment, that will look at safety
over the period of time that -- there they go again. Are we okay now or
MR. LEE: We still haven't heard you.
MR. FAIRHURST: What period of time do these analyses -- or
impacts, what periods of time do you traditionally look at?
MR. GREEVES: I'll answer the question. There is no cutoff.
MR. GARRICK: Could you focus the camera on Mr. Greeves?
MS. WASTLER: San Antonio, I'm sorry, but we lost you again.
MR. HORNBERGER: We'll try it on this end.
MR. FAIRHURST: John Greeves said he can answer the
MR. GREEVES: The question was, is there any timeframe for
these EIS reviews. This is John Greeves, Director of Waste Management.
Are you picking me up with this mic okay?
MR. CAMPBELL: The court reporter is okay.
MR. GREEVES: The answer to your question is that there are
no time limits.
MR. LEE: San Antonio?
MR. GREEVES: They just asked how long the EIS time period
would cover, and the answer is there's no limits.
MR. LEE: That's correct. Right now, we expect that DOE
would do an analysis of impact through peak dose, that's for the
post-closure. Jim, did you want to add something? Beyond 10,000 years,
DOE is planning on looking at the results qualitatively, not
MR. FAIRHURST: Well, what about issues like transportation?
You're not going to worry about transportation over -- presumably, that
has a finite time and then you've got the repository flow, right?
MR. GREEVES: It's whatever makes sense for that particular
technology. We would do for transportation what we would do for a
nuclear power plant.
MR. FAIRHURST: And this would be in any kind of previous
environmental impact statement, non-nuclear issues.
MR. GREEVES: In transportation issues, there was, I think,
a generic EIS that covered that for transportation issues, other issues.
I'm not the expert on it, but, yes, there's been EIS's evaluated for
things like transportation, chemicals.
MR. HORNBERGER: The real question is, are there examples of
EIS's that have covered a 10,000 year period.
MR. FAIRHURST: Thanks, George.
MR. GREEVES: I don't think -- I don't know of any, other
MR. FAIRHURST: Radiation business.
MR. GREEVES: The chemical business doesn't do it. They
look at about 30 years.
MR. HORNBERGER: Are there examples in the radiation
business? Are there examples of EIS's that have been done for low level
MR. GREEVES: We have not done a low level site. They've
been done by the states.
MR. FAIRHURST: My concern is that somebody doesn't invent a
whole new set of requirements just because this happens to be a nuclear.
It goes way beyond what one would do for any classical environmental
My understanding for the radiological hazard, but whether
one starts then saying the impacts on a population at that time, you
have this fully hypothetical situation of a population, it doesn't make
sense at all.
My question was really how it got defined.
MR. CAMPBELL: A point of interest. Did WIPP have to do an
MR. FAIRHURST: They said there wasn't any, because there
are no relations, except by human intrusion.
MR. CAMPBELL: Did DOE have to do an EIS for WIPP?
MS. DEERING: Any significant environmental --
MR. FAIRHURST: I think we need to look at that.
MR. LEE: If I might just add. We haven't been able to
follow your dialogue there very clearly because of the breakup in the
communication, but in preparing the EIS, we expect DOE to follow the CEQ
guidance on what an EIS should cover, the period for which it should
That includes both any regulations, as well as implementing
memorandum of guidance. So I don't know if that helps you or answers
your question or contributes to the response that you got.
MR. FAIRHURST: Are you saying that the CEQ has established
rules? Are they real established rules for this particular case?
MR. LEE: They have general guidance on what an
environmental impact statement should cover. They don't have specific
guidance on what a repository EIS should cover or transportation or
anything like that.
All right. Well, slide six. As I alluded to earlier, the
staff is in the process of preparing some proposed review guidance that
would be used to evaluate DOE's draft environmental impact statement and
what we're proposing is one review that would consist of two components;
a completeness review and what we're referring to as an evaluative
In terms of the completeness review, as I mentioned earlier
in response to a question from Dr. Garrick and Dr. Hornberger, we expect
to do a comprehensive evaluation of the EIS to make sure that it's given
due consideration to all potential environmental impacts.
In conducting that review, we'll rely on guidance that CEQ
has provided. That review, in some respects, will be an audit type of
review, to make sure that DOE has a placeholder for all of these
In its evaluative review, the staff will do a more detailed
evaluation of the content of the EIS. That would include an evaluation
of data, data-gathering methods, and data analysis techniques.
We hope to confirm that the data and analyses that are
included in the EIS support the conclusions that are advocated or
proposed in the EIS. We'll also evaluate impacts and any mitigation
proposals that DOE is presenting.
This review, of course, would be a function of how much we
can do in that 90-day public comment period. As part of the development
of this review guidance, we have a task force in place, as I mentioned
earlier, with SFPO, OGC and the center. As the guidance is being
finalized, it will be transmitted to the Commission and we expect copies
will be provided to the committee for its information.
I believe that was the same format, more or less, that was
followed for the VA review.
On slide seven is the proposed schedule that the staff is
going to adhere to in the review of the draft EIS. Again, we're
following the same format, more or less, that was used for the VA. We
expect to transmit the proposed guidance to the Commission in mid-July.
Our current understanding is that DOE intends to issue the draft EIS for
public comment on July 30.
With respect to post-EIS receipt activities, again, these
dates are contingent on the receipt of the draft EIS or the issuance,
rather, of the draft EIS in July. As was the case with the VA, we
expect to conduct a technical exchange with DOE, rather, in the August
timeframe to discuss openly any proposed comments or questions we have
with respect to the DEIS.
We're currently scheduled to brief the ACNW, I think
September 14 is the date that we are looking at. DOE has committed to
brief the Commission on September 15.
We expect, as part of our review process, to conduct a
series of public meetings in the Nevada area. The exact number and the
location is still being worked on. But this week is a week that DOE
doesn't plan on having any of its public hearings and as a consequence,
we thought that would be a good week to be at Nevada.
So those that aren't aware of it, DOE is proposing 14 public
hearings, both locally and nationally, as part of the public comment
process on the DEIS. Seven are being held in Nevada and then the other
seven are to be held nationally, including, I think, one in Washington,
As part of the staff's review of the draft EIS, we intend on
attending or monitoring most, if not all of these public hearings.
Earlier on the schedule, we expect to brief the Commission
on October 12. We would expect that the ACNW, as part of its
deliberative process, would brief the Commission at some time in
October, at a time that you all work out with SECY, and the public
comment period ends, I guess, October 28.
We do know that the State of Nevada has already requested
that the public comment period be extended. We know that DOE is
preparing a response at this time. We don't know what the nature of
that response is.
MR. FAIRHURST: Well we asked quite a few questions during
MR. GARRICK: Mike, I don't think you're expecting any
comments or a letter between now and when we get briefed in September,
but we might want to do something following the September meeting. Is
MR. CAMPBELL: He's startled.
MR. WYMER: He's frozen.
MR. GARRICK: How come it worked so well yesterday
MR. LEE: We're back.
MR. GARRICK: We were just raising the question of actions
by the committee. I don't think we're in much of a position to say
anything at this time as far as a letter is concerned, but we probably
will following the September briefing. Is that what you're expecting?
MR. LEE: Sure. I think -- yes, that's correct. I think
one of the challenges for the committee is to define what its role is in
the review of the draft as the staff is doing its parallel review.
MR. GARRICK: Right.
MR. LEE: As I noted earlier in the opening remarks, the EIS
or the DEIS, rather, isn't falling into this nice, clean KTI format. In
theory, all the KTIs are preserved, because we're focusing on both
post-closure and pre-closure impacts with respect to the EIS itself and
the KTIs ultimately roll up in that regard.
But as I said, the focus now is more on performance or dose,
I should say.
MR. GARRICK: Have there been any -- much exchange between
NRC and DOE on the issues and content?
MR. HORNBERGER: They're gone. Are you back?
MR. GARRICK: What has been the level of exchange between
the staff and the DOE on the EIS?
MR. LEE: Essentially, none. DOE -- for everyone's benefit,
NRC conducts all its interactions, both at staff and management levels,
in public forums. The DOE has made it clear that given the nature of
the information that's in the EIS, they -- I guess the short version is
they haven't been willing to meet with us because they know that the
meetings would be public meetings and they don't want to disclose the
content of the EIS until it's available for public comment.
So because the staff isn't going to interact with DOE in a
non-public fashion, we've had -- the only interaction we've had have
been at TRB meetings, where we can hear the presentations at the same
time the public has.
We're assuming that -- yes?
MR. FAIRHURST: Keep going.
MR. HORNBERGER: I just wanted to ask, Mike, is it a single
contractor who has done the DEIS for DOE?
MR. LEE: I believe it's multiple contractors. Wendy
Dixon's group is the lead within DOE for preparing the EIS. I know that
for the post-closure dose assessment, they relied on PNL. I think that
Jason & Associates is the lead subcontractor under the M&O for preparing
But in terms of the number and types of subcontractors that
DOE relied on, it's not really clear to me. I know those two.
MR. FAIRHURST: How does the dose assessment for the EIS --
maybe I'm missing something -- differ from the assessment that's being
done through performance assessment? What's the difference?
MR. LEE: We're back. Okay.
MR. FAIRHURST: I was wondering. Could you explain a little
bit -- it may be difficult for you to explain, since you've had no
dialogue with them, but you say PNL is doing the post-closure dose
assessment part of the EIS. I'm saying, how -- does that mean that
they're doing a totally independent analysis of the performance
assessment or what?
MR. LEE: It's my understanding that what PNL is -- I can't
speak for DOE, but it's my understanding that what DOE has done is the
performance assessment capability that was being developed under Abe Van
Lube, that capability was copied, more or less, in the code, in the
model, the data, and handed off to PNL and PNL, working with the EIS
team, exercised that same capability, data, models, whatever, for the
purposes of their post-closure performance assessment.
They're working with the same capability, more or less.
They just had other hands exercising it.
MR. FAIRHURST: So it's, in essence, a semi-independent
check of calculations, right?
MR. LEE: I wouldn't know. I can't answer that.
MR. REAMER: There's no difference, theoretically. But all
of this is pretty speculative. I want to underscore that we have not
had the interaction with DOE on the document. We can try to speculate
and answer your questions as best we can, but really it's the Department
of Energy that holds the answer to your questions. It's not the NRC
MR. FAIRHURST: And part, I think, of the committee's
problem is that we're asking questions when we haven't seen anything and
you haven't seen anything and we're all guessing, trying to somehow
respond to the presentation.
MR. GREEVES: May I ask? Does the committee have a --
MR. LEE: I mean, one of the -- this is unlike the VA. With
the VA, it was telegraphs, we had a lot of experience reviewing
background documents and a number of interactions leading up to the
review of the VA. This is a different situation, again, because of
DOE's desire to keep the EIS non-public until it's available for public
We didn't have the luxury this time of involving ourselves
with DOE and getting a better appreciation for the types and kinds of
information and the conclusions that it might contain.
MR. GREEVES: Who would be a lead member on this topic?
We'd like to keep you informed. In the past, you've sort of selected a
lead member on a topic. So the one who is asking the most questions is
maybe a candidate?
MR. FAIRHURST: That's only because they told me I had to
MR. GARRICK: Mike, what would happen if the EIS performance
assessment was substantially different than what we're hearing about
now? Just to follow-up on Charles' inquiry.
MR. FAIRHURST: That's right.
MR. HORNBERGER: Nobody knows.
MR. LEE: Who is to say? I mean, quite frankly, we're
working under the assumption that the EIS is going to contain no
surprises. We understand that the EIS is going to rely on the same
data, models and codes that were being developed in site
characterization space, as well as other information that's being
collected by DOE as part of its environmental impact site
We don't expect any surprises.
MR. GARRICK: Isn't the EIS going to have --
MR. LEE: I can't -- I don't --
MR. GARRICK: Isn't the EIS going to have the same problem
that you're having? Namely, it's going to be a snapshot of a design
that probably is no longer valid.
MR. P. LEE: If I could, sir. We're going to fix this. I
am rebooting and having about five minutes worth of my equipment reset
to try and clarify this.
MR. GARRICK: Yes. Mike, we're going to take a five-minute
break and see if we can improve the communication.
MR. LEE: Okay.
MR. GARRICK: The meeting will come to order, please.
We were talking, Mike, a little bit about the instability of
the design and the implications of that with respect to the EIS. I
suspect it's no different than any of the other issues we've been
dealing with in that regard.
MR. LEE: The only thing I would say is that we know that
DOE is going to consider a number of design alternatives for purposes of
bounding potential impact. So even though the design may still be in
flux, I think the intent of the EIS is to identify potential impacts and
try to articulate some bounds on what those impacts might be.
I don't think there is a big problem there.
MR. GARRICK: One other area that we started discussing and
maybe we can hear some more comment on is that eventually, even though
there are restrictions on the NRC jurisdiction and the implications of
the rule-making that took place with respect to expertise and
jurisdiction some several years ago, eventually, the NRC has to adopt
Now, what do you do if, on the one hand, you're satisfied in
accordance with the rule and your expertise and the area of
jurisdiction, but, on the other hand, you know there are some other
things outside your jurisdiction that you're uncomfortable with, and a
lot of those things you don't have to be an expert in to at least have
some insight and understanding of that?
How do you deal with that? How do you deal with the
situation where, according to the letter of the law, you've satisfied
the requirements, but from a technical standpoint, you just know
something else isn't complete or meets the high standards of the Nuclear
MR. LEE: Well, without specifics, I would say that as part
of our review of the draft, we would hopefully identify any and all
areas for which we had some degree of uncomfortableness and comment on
those areas during the review of the draft.
For its part, we anticipate that DOE, in evaluation of
public comments, would prepare, as parts of its Federal Register notice
announcing the availability of the final EIS, would have some
administrative record on how it addressed and responded to each of the
Be that as it may, though, once DOE issues its final EIS, we
expect, and this is stated, I guess, in the statute, that there would be
the potential for judicial review and litigation of any issues that
were, in the opinion of litigants, not satisfactorily addressed.
So we wouldn't be involved in that. The statute has said
that falls under the purview of the courts of appeal.
I mean, is there some area specifically that you're
MR. GARRICK: Well, one of the things that we have been
sensitive to in the nuclear field is that sometimes there is the feeling
that the nuclear standards are very much different than other standards
in terms of the high level of safety requirements and, of course, the
EIS is going to address a lot of other issues than nuclear safety and
So the only thought there is that -- is this an opportunity
to try to begin to introduce concerns and questions that would be
constructive with respect to moving in a more harmonious direction with
respect to issues of risk and safety.
I realize that --
MR. LEE: Well, I think we all have to remember what the EIS
is intended to do or the role it's intended to serve in the program, and
that's as a decision-making tool for DOE as part of its deliberative
process on suitability of designing and building and operating a
repository at Yucca Mountain.
Issues related to public health and safety are covered in
NRC's regulations. So I think that that dialogue is taking place right
now. DOE knows it's going to have to implement NRC's regulations and
we've had, over the last two decades, many meetings and exchanges on how
NRC's regulations would be implemented or what we would expect, even
though we have a new regulation being proposed, the level or the
standard of demonstration that DOE would have to meet.
DOE knows they have to be transparent in their
decision-making and that their demonstrations need to or should be
subject to the rigor and evaluation following the scientific method. We
should be able to take their data, methods, models, and implement them
and come up with the same conclusions that DOE does.
MR. HORNBERGER: Mike, to go into a licensing, does, in
fact, NRC have to adopt the EIS and if so, could you clarify for me a
little bit what the word adopt actually entails?
MR. LEE: I think I'm going to defer to our resident
attorney, Neal Jensen, who happens to be in the audience, who could talk
a little bit about the adoption process.
There is guidance in 10 CFR 51 about what that adoption
would involve. Here is Neal.
MR. JENSEN: The Commission issued regulations in 1989
governing its process for adopting DOE's EIS. We are legally mandated
to adopt it to the extent practicable. We placed, at that time, in our
regulations, the standard by which we would judge whether it was
practical or not, and that's 1109-C of our regulations, which I'm
looking for at the moment.
That provides that we will find -- or the presiding officer
at the hearing will find that it is practical to adopt DOE's EIS, unless
one or two events. First, the action proposed to be taken by the
Commission differs from the action proposed in the license application
submitted by the Secretary and the difference may significantly affect
the quality of the human environment.
Or the second problem that might prevent us from finding it
practicable to adopt is if we were to find significant and substantial
new information or new considerations rendering such EIS inadequate.
So what the committee has said is that barring one or the
other of those two findings, we will find it practicable to adopt the
Now, the Commission has also said that, for example, if new
information should come to light between the time DOE submits the
application and the time of the licensing hearing, we would anticipate
that DOE would supplement its EIS and take account of that new
information and we would adopt the supplemental EIS under the same
MR. HORNBERGER: Thank you.
MR. FAIRHURST: So you are able -- I mean, DOE is able to
submit the license application while there are issues still being
resolved with regard to an EIS. Are the two enough linked or is that --
MR. JENSEN: DOE's final EIS is anticipated, I believe, in
July of 2000 and the application is, I think, to be submitted in 2001 or
2002. So hopefully, there won't be substantial new information that
will affect the final EIS. But if there is, then our regulations call
for DOE providing a supplemental EIS to take account of the new
MR. FAIRHURST: And so you can adopt that. There is no time
linkage, but you have to adopt it before you proceed to examine the
license application. Is that what I'm hearing?
MR. JENSEN: No. The adoption takes place in the context of
the licensing decision. It would be adopted in the decision of the
MR. FAIRHURST: I see.
MR. JENSEN: Which, of course, that would be reviewed by the
MR. FAIRHURST: NRC has, what is it, three years to make a
determination on the license application?
MR. JENSEN: Right. The regulation in 51.109(a) provides
that when we issue the notice of hearing, the staff, at that time, will
announce its decision as to whether the staff believes whether it is
practicable to adopt DOE's EIS.
Opposing parties may then disagree with that and then have
an opportunity to submit contentions demonstrating their position that
it is not practicable to adopt, and then that issue will come before the
MR. FAIRHURST: I see. So people can challenge. So
intervenors can challenge NRC and the hearing officer is the one that --
MR. JENSEN: Yes.
MR. LEE: But not in the EIS. On the license application.
MR. FAIRHURST: They can't challenge --
MR. JENSEN: Whether or not it's practicable for us to
adopt. Not the issues in the EIS, but whether it is practicable --
assuming staff takes the position that it is practicable for the NRC to
adopt the EIS, that staff can be challenged in the licensing proceeding.
MR. FAIRHURST: But you can go ahead and examine the license
application while that challenge is being resolved.
MR. JENSEN: Yes.
MR. FAIRHURST: Okay.
MR. GARRICK: All right. Any other questions? Any
questions from the staff?
MR. LARSON: So you do have 51.109 in your notebook back in
Section I, but it's in with 51 and among the hundreds of pages. You
will find similar words.
MR. GARRICK: All right. Thanks a lot, Mike. Unless there
are other questions, I think we're through with that topic now. We were
expecting that --
MR. RUSSELL: A question.
MR. GARRICK: Yes.
MR. CAMPBELL: You're going to have to go to a microphone,
and it's not that one.
MR. RUSSELL: I think it's a trivial question. I was
noticing that the NWPA doesn't require the DOE to consider alternatives,
and yet when you were discussing the other possible issues that might be
considered during the review, you mentioned alternatives. I'm not clear
on the disparity there.
MR. GARRICK: Would you give your name?
MR. RUSSELL: Blaine Russell. I'm a consultant here at the
MR. GARRICK: Okay.
MR. LEE: DOE Is required to consider design alternatives in
its EIS, but not alternatives to geologic disposal. Does that answer
MR. RUSSELL: Thanks.
MR. HORNBERGER: And not alternative sites, is that right?
Alternative designs you're talking about.
MR. LEE: That's correct. Alternative designs, in the
context of Yucca Mountain, but not alternatives to Yucca Mountain.
MR. HORNBERGER: Right.
MR. GARRICK: Any other questions?
MR. GARRICK: Okay. Thanks, Mike.
We had scheduled to break for 10:00. We're a little ahead
of schedule, which I'm encouraged by, because it will give us more time
for our one-on-one that I think we would like to have.
If Keith McConnell is ready, I think we'd like to move
directly into the discussion of defense-in-depth.
MR. McCONNELL: For the record, I'm Keith McConnell. I'm
the Section Chief for Performance Assessment in NRC's Division of Waste
MS. WASTLER: I'm sorry, Keith. What's the question?
MR. McCONNELL: There is no question.
The way I was going to approach this part of the
presentation is have a little bit of introduction and then Tim will go
through a review of what's in Part 63 and discuss it, as far as
defense-in-depth requirements, and then I will come back and I will talk
about basically the plan that's being developed within the Division of
Waste Management to address defense-in-depth and clarify the
So it's kind of a three-part presentation. It's going to
end up being relatively short, also, I believe.
MR. GARRICK: Okay.
MR. McCONNELL: So, again, our purpose here today is to
initiate the dialogue with the committee on our efforts to clarify the
requirements for defense-in-depth for the proposed repository at Yucca
I think as the committee and others are aware, over the past
couple of months, since Part 63 was issued for public comment, a number
of issues have been raised about the particular requirements; for
example, whether they are sufficient to provide for defense-in-depth for
a repository. Also, there were questions about what the staff
expectations were for defense-in-depth and how we expect DOE to
The most prominent venue for those comments and questions
was the Commission meeting that was held in March on DOE's viability
assessment, where the committee and other stakeholders addressed this
particular issue and I think raised a number of these comments and
One of the outcomes and the principal outcome from that
meeting was direction from the Commission to the staff in the form of a
staff requirements memorandum that we evaluate how we could more clearly
address the issue of defense-in-depth in our requirements in Part 63 and
to foster a common understanding of that term.
I would note, also, that in our public meetings on Part 63
that we had in Nevada in March, that this issue was also raised and was
a prominent issue at those meetings.
This, in essence, this presentation is kind of a precursor
of our response. We've developed a draft plan to address
defense-in-depth. It's now in concurrence within NMSS, so it's likely
to change. There is not all that much substance in it at this point,
but be assured that we do intend to come back to the committee later in
the year to discuss more substantive aspects of defense-in-depth.
Unfortunately, if you listened to the EIS schedule and you
look at the schedule that I will present a little bit later, scheduling
all these things so that they don't conflict is going to be a challenge
in itself, I believe.
I guess if there are no questions or comments at this time,
I'll turn it over to Tim, who will go through what's in Part 63 with
respect to defense-in-depth at this time.
MR. McCARTIN: I'll be discussing, as Keith mentioned, the
approach we had when we proposed Part 63, and I'd like to touch on four
First, I'll talk about the definition of the
defense-in-depth concept, what's required in Part 63, then, plus, some
specifics about the requirements for multiple barriers, and then what
quantitative approaches are possible for demonstrating multiple
With that, everyone is familiar with the Commission white
paper on risk-informed performance-based regulation, and in that paper,
they did define the concept of defense-in-depth and I highlighted,
although there's a lot of words here, I tried to highlight aspects that
we believe are applicable to the approach for disposal of high level
waste and multiple barriers, from employing successive compensatory
measures to mitigate damage if there is a malfunction or
naturally-caused event; ensure that safety will not be wholly dependent
on a single element; and, the facility or system in question has to be
more tolerant of failures and external challenges.
And all those aspects and the philosophy of
defense-in-depth, we believe, we accomplish through requiring the -- the
requirement for multiple barriers.
Specifically, what is in the regulation, and Part 63 is
relatively simple in its requirements. There is a 25 millirem annual
dose limit that is estimated through a performance assessment. That
must include an analysis of uncertainty in those dose estimates.
Secondly, there is a demonstration of the capability of
multiple barriers. Multiple barriers imply and are required to be both
engineered and natural, and a stylized calculation for human intrusion.
This point is a little more detailed. What the regulation
requires for multiple barriers; very simply, a barrier is defined as any
material or structure that prevents or substantially delays movement of
water or radioactive material. That is what makes it a barrier. There
are -- as we've done, there are no quantitative requirements for
individual barriers; however, DOE is required to identify the barriers,
describe their capability, and provide the technical basis for the
capability of that barrier.
This affords DOE flexibility to identify and take credit for
whatever barriers they want and select whatever approach they believe is
appropriate for demonstrating that contribution.
With that flexibility, which is what we tried to provide in
Part 63, DOE has that responsibility. We aren't dictating to them what
to do. And I think -- what are we thinking about when we talk about
this demonstration of multiple barriers?
First, what we had in mind was DOE will do a performance
assessment. In that performance assessment, they are going to make
assumptions about the behavior of the engineering and the natural
system, some aspects of that system will act as barriers, and it's in
the context of the performance assessment that we're expecting this
analysis to be done.
Specifically, the barriers should be representative of
distinct features, characteristics or attributes of the repository
system. For example, the engineered barrier unsaturated zone, alluvium
of the unsaturated zone, we weren't looking for -- we were looking for
broad categories. We were not expecting an analysis -- you could go to,
gee, is each waste package a barrier.
You have the inner container, the outer container, a ceramic
coating, the cladding, the fuel itself, a drip shield, the unsaturated
zone; do you have every individual layer, every ten meters of the
saturated zone, is that a barrier.
We are not looking to have barriers defined in a very fine
fashion, but looking at more broader attributes. And by that, you can
look at the capability of barriers, and that second point, should be
explained in terms of the definition of the barrier, which is preventing
or substantially delaying the movement of radioactive materials or
For example, the waste package delays releases for many,
many years. The unsaturated zone shields the repository from a lot of
water. Deep percolation is only a small fraction of the annual
precipitation. That also contributes to performance.
The unsaturated zone limits the number of waste packages
that get wet. Just the natural system itself, its heterogeneity, water
doesn't rain down into the repository. We do not expect all the
packages to get wet.
Thereby, that unsaturated zone limits the number of packages
that get wet and thereby limits the radioactive waste that's available
for release to the ground water.
And, lastly, the alluvium in the unsaturated zone
significantly delays many of the radionuclides by absorption. For
example, although there are certain radionuclides, such as iodine,
technetium, neptunium, that may be slightly retarded, the vast majority
of radionuclides in the inventory never make it to the critical group
because it's retarded in the alluvium; not because they didn't get out
of the waste package, but there is retardation in the geosphere that
prevent them from ever getting there in 10,000 years.
Lastly, we believe that a risk-informed approach, the rigor
needed to defend the barriers' capability should be proportional to its
importance to performance.
And what does DOE have to do? We're looking at laboratory
field measurements that certainly can be done for some attributes,
analog studies certainly can be brought forward to give some basis for
why we believe that capability exists for that particular barrier.
And, finally, quantitative approaches. There are many ways
to illuminate, provide insights in terms of a barrier's capability and
how it is affecting the overall performance of the facility. There are
safety analyses where you can look at parameters, alternative models,
the importance analysis that Norm, I think, appropriately said the other
day, that it actually is another form of sensitivity analysis.
DOE has done one-off analysis. Our regulations of 10,000
year compliance, maybe you do some analyses beyond 10,000 years to show
attributes of how the barriers are functioning.
All of those are possible. We have not dictated to DOE how
to do that demonstration. It will depend on what types of barriers,
their analysis, information that is still coming in. We're open to any
approach that makes the PA and the capability of the barriers they've
used more transparent and supports a more informed licensing decision,
but we're relying on the DOE. It will be their analyses.
Although we know what we might do with our particular code,
it isn't the DOE's code and they will have -- they have their code,
they're the experts with their code, they'll have to make that
determination; what illuminates the multiple barriers the best and most
With that, that's -- I don't know if we want to take
questions now or after Keith's presentation.
MR. McCONNELL: I'll leave it up to the committee. I think
this is the more technical part of the discussion here. So I assume, if
you have technically related questions, it might be appropriate to
address them now.
MR. GARRICK: The only comment I want to make is that this
committee was in very strong support of the elimination of subsystem
requirements, but I think sometimes what's lost in that is we were also
in very strong support of understanding quantitatively the performance
of individual barriers.
And I think sometimes when we present this material, there
is the implication that we might be going backwards here, and that's
just not the case.
When you say no quantitative requirements for individual
barriers, what we're -- the emphasis, of course, is on the requirements.
On the other hand, we are pushing very hard that we quantify the
performance of individual barriers.
So I just wouldn't want either the public or anybody else to
get the impression that the committee is moving away from
quantification. On the contrary. We're pushing very hard that it's not
the requirements that's important, it's understanding what the
performance of these barriers is, and we are in a much better position
now to quantify that than we ever have been before, and that should be
MR. McCONNELL: I think we've heard the committee. Tim, let
me start, and I'll shift it. I think we've heard the committee. I
think our overall goal in all these efforts is to not reintroduce
subsystem performance objective into the rule.
MR. GARRICK: Right.
MR. McCONNELL: But we also have heard you, from your March
'98 and October '97 letters, that you do want quantification, and I
think the post-processor, that I guess will be discussed this afternoon,
is an attempt to bring this quantification out and to make the analysis
more transparent, but more in the context of how we would review a
Sorry, Tim, go ahead.
MR. McCARTIN: I don't know if I have much to add. I think
we certainly do agree that we want things to be quantified. And we
certainly struggled in writing Part 63, where you don't have
quantitative requirements, how do you work in what you want to see.
And what we've heard, I think, so far, in the comments we've
heard, is that we left it purposely fuzzy so that DOE had flexibility to
select particular approaches. Somehow we need to try to better explain
what we want to see in terms of illuminating the understanding of how
the barriers are functioning and we'll obviously be talking to the
committee, as well as responding to the public comments, trying to give
a better explanation.
But it's difficult to get that into words in the rule and
we're open to suggestions. We're hoping we get, both from the
committee, we hear you, and the public comments, we're hoping we can
improve that tone in the regulation.
MR. GARRICK: Thanks, Tim.
MR. HORNBERGER: Tim, I was interested to read -- I guess
it's the final draft or the penultimate draft of Jack Sorenson's paper,
and it strikes me that what you're doing is you have an opportunity here
to take the rationalist approach, as described by Jack, and not be
shackled by the so-called structuralist approach because of prior
Do you view it that way, also, to try to move it in that
MR. McCARTIN: I don't know if I've read that paper. Was
that the ACRS paper?
MR. HORNBERGER: Yes. I'd recommend it to you.
MR. McCARTIN: Yes. I have read it. I didn't know -- I
don't recognize the author's name. But, yes, I think we agree with
MR. GARRICK: Okay. Anymore questions before we turn to
MR. HORNBERGER: We'll wait until Keith is finished and ask
some questions then.
MR. GARRICK: Okay.
MR. McCONNELL: What I'm going to do is address basically
the plan that we're developing in response to the Commission direction
and what I will attempt to do is respond to four questions; what are the
underlying bases for implementing defense-in-depth, and I think we've
probably already addressed that in Tim's presentation; how will we
clarify our expectations for demonstrating defense-in-depth through
multiple barriers; when and how will the clarifications be made
available to the public and other stakeholders in this process; and,
what is the schedule of planned activities.
With respect to the underlying bases for implementing
defense-in-depth, as Tim indicated, we're going to ensure that the
Commission's white paper on risk-informed performance-based regulation
is a part of our regulation and our Yucca Mountain review plan.
It was issued after the proposed rule was put out for public
comment, but we think that the rule probably embodies the philosophy
that the Commission had in that white paper, and also the requirements
in the proposed Part 63.
We haven't looked at public comments to date, but our
expectation is right now, I guess in ignorance of those public comments,
that the requirements in Part 63 wouldn't change substantially. But,
again, our overall goal is to avoid the imposition or reimposition of
subsystem performance objectives in the regulation.
How will we clarify our expectations for demonstrating
defense-in-depth through multiple barriers? Again, in response to
public comments, we'll refine the requirements as needed. But more
importantly, we're going to use the Yucca Mountain review plan and the
acceptance criteria and review methods in that review plan as the
primary context. We will define how we will review defense-in-depth and
what we expect DOE to demonstrate for those particular requirements.
I would, I guess, point out that it's not unexpected that we
receive comments on defense-in-depth. I think we anticipated that when
we drafted the proposed rule, because it is such a substantial change
from what's in Part 63, and in the SOC, we indicated that we were
developing the Yucca Mountain review plan and would provide more
detailed guidance in that review plan.
When and how will clarifications be made available to all
stakeholders? Well, you're probably aware we had a technical exchange
with DOE in May, where we discussed defense-in-depth in brief, and they
laid out on the table some of their techniques that they're using to
implement defense-in-depth. We do intend to coordinate with the
advisory committee, as well as the joint ACRS/ACNW Committee on
Risk-Informed Regulation, as well as NRR and others within the agency.
We also intend to have a public meeting in Nevada to discuss
the Yucca Mountain review plan in general and the approach to
defense-in-depth in particular.
Again, scheduling that meeting amongst all the EIS meetings
and not conflicting is going to be a challenge for us, because we've
heard from the public out there that all these meetings can become
burdensome for the participants out there. So we'll see what happens.
With respect to the schedule of planned activities, again,
this is proposed. It's in concurrence within NMSS, so it could change.
The top three have basically been done. We won't go through all of
these, but I would direct your attention to four and five. Four and
five note where we're going to speak internally and externally about our
approaches and gaining information from other stakeholders in this
process, to make sure we're consistent in approach within NRC, and also
that we've gotten the views of the public and other stakeholders.
Also, I'd direct your attention to numbers seven and eight.
Number seven basically notes that we intend to come back to the
committee prior to the issuance of the final rule on Part 63 -- not the
issuance, I'm sorry -- the completion of the draft rule that would be
submitted to the Commission, to discuss our approach or proposed
approach and get your input at that time.
I think we will probably be communicating with you
informally before that, as we have done on other topics.
And then number eight, our, I guess, conclusion is that we
expect to complete a proposed approach to clarification of
defense-in-depth by November and include it in the package that goes to
the Commission on the proposed final rule at Part 63.
So basically, over the next six months, we've got a lot of
work to do in defense-in-depth and in review of the draft EIS, as does
the committee and the committee staff.
So if nothing gets delayed, we have a lot of interesting
times ahead of.
That's basically the end of my presentation. Tim, do you
have anything to add?
MR. McCARTIN: No.
MR. McCONNELL: So I'd open it up for comment.
MR. HORNBERGER: Great. Keith, could you perhaps expand
just a little bit on what you learned in the technical exchange a month
MR. McCONNELL: Well, as you know, DOE has been attempting
to implement an importance analysis type of approach to demonstrating
defense-in-depth. They discussed that with the TRB several months ago
and they expanded on that discussion in the technical exchange, and I
would probably defer to Norm and Tim, but my perception was that it was
a refinement of what Norm and Budhi are working on, where they do
neutralize either a barrier or a component of a barrier and then compare
the results of that analysis with the overall -- or with the nominal
case, in essence.
So, again, the relative importance of a particular barrier.
Budhi, do you -- Tim or Norm?
MR. McCARTIN: I guess I would only add one thing that I
thought we got from the tech exchange; that in talking about the
neutralization, one of the things that I think -- you need to be very
careful when you start neutralizing the barriers and one of the reasons
the previous DOE TRB numbers that were showing very high doses,
neutralizing one of the barriers somewhat caused another model in the
system to be invalid, because they never anticipated that that would be
the case, that that barrier would be neutralized.
Basically, they were getting a very large diffusional
release of waste, but the reason they used that model is they never
expected it would be invoked that early in the performance period. So
although they effectively neutralize the waste package, the model, the
diffusional model then was somewhat invalid for the conditions they
removed from it.
So you have to really be careful of your results, and I
think that's the one thing I believe -- and that's why I think we want
to leave the flexibility to DOE. It's their model. They've got to
figure out what works with that.
But you do have to be careful when you start -- you have a
lot of flexibility in models, but you just can't necessarily start
turning switches every which way and not understand the implications
downstream, if you will.
MR. FAIRHURST: Have you given any thought as to how that
particular example, how you would deal with it in what you might call a
If I recall what they did at that time, it's take out the
waste packages at year zero or something and said just put this waste
into drift, which --
MR. McCARTIN: Right.
MR. FAIRHURST: -- is a challenge, the potential for all of
those waste packages to fail like that is zero. I mean, the probability
would be zero.
So how do you propose to deal with that?
MR. McCARTIN: Well, if they still want to do that type of
analysis, and I'm not saying whether they should or shouldn't, but given
you're going to do that, I think they have to look at their diffusional
release model and make sure it's still valid in the situation they have.
It wasn't, and so they were getting tremendous releases when
they really shouldn't have, and that, to me, was the problem. I think
they'd have to go back and have a different type of -- they'd have to
revise their release model.
MR. GREEVES: John Greeves. We actually seek your feedback
in this process. Just individually, I have trouble with doing
evaluations that are just not physically possible. I think we should
tell DOE don't do that. It just doesn't make sense. If there is an
analysis where you assume everything fails on day one, shouldn't we tell
them not to do that?
MR. FAIRHURST: No.
MR. GREEVES: There ought to be some bounding process here.
MR. FAIRHURST: What I was trying to provoke with the
question is, you're absolutely right, you put tons of metal in there,
and tons of metal is not suddenly stolen. If they can fail more
rapidly, how do you take it out of the system to evaluate its
MR. GREEVES: In a feasible fashion. Taking these
approaches where you remove barriers that are physically there.
MR. FAIRHURST: I agree.
MR. GREEVES: We'd like some feedback from you on that.
MR. HORNBERGER: I would think that Budhi or Norm would be
jumping up and down about now. But I think that when we heard Norm, was
it yesterday, I mean, he was very careful to point out that this was not
an analysis that was to be realistic. It was a form of analysis to try
to gain insight into a relative contribution of a barrier.
So it's almost a very stylized kind of -- well, it's not a
-- well, it is a kind of sensitivity analysis, I guess. Norm used that
word, so I guess I can safely.
MR. FAIRHURST: But, George, if you take it out at 10,000
years or 5,000 years, it's a very, very different barrier than it is in
MR. HORNBERGER: I know. I don't think that either Budhi or
Norm would argue that the state of the analysis right now is the end. I
think they've put forward a method that is to be judged to be a
possibility of a kind of approach, and I think that's what Keith and Tim
are trying to grapple with now in Part 63, to give some indications of
an approach or a series of approaches that DOE might use, not that they
have to use.
It's not -- that's my reading of it. I don't mean to speak
for you, Keith. You answer the question.
MR. McCONNELL: No. I think you're correct. I think you're
correct, except that it would be -- it's not only direction to DOE.
It's also direction to the staff in the sense that it's going to be how
we review what DOE does to implement defense-in-depth. We might take a
different approach than what DOE does just to provide an independent
view of what level of defense is provided for.
MR. SAGAR: I guess I have to come there. Budhi Sagar, with
the center. I completely agree with Tim. I think we've tried to find
that out during Norm's presentation, that when you do something to a
barrier, you have to make sure that the rest of the model is valid, no
question about that.
And there may be codes which may not be designed to do that.
So that's why we said it's not the post-processor. You have to go back
and do something to your code for this to be effective. All that is
agreed to. But to John Greeves' issue, again, so long as we understand
that this is not a realistic analysis, it has to be stated up front what
you are doing.
You're not trying to tell something to somebody that's not
true. But you are trying to say what if, what if this happened, what do
I get, and it's just a matter to say the values help us to reduce the
dose by X amount, and that's all it's telling you.
MR. FAIRHURST: But you know what happened when that --
taking away the canister was discussed. Immediately, the intervenor
said, see, it's a bad site.
MR. SAGAR: And the intervenor may be right, for the site
point of view. Why are we so afraid of that? If you take away the
waste package and you get a huge release, okay, the site is not so good.
But that's what we would get.
Now, if they did the analysis wrong, which is what Tim is
saying, that doesn't say the site is wrong. That says the model is
wrong. You have to differentiate between those two. But the site can
be bad and the engineered barriers can be bad. How do you judge that?
MR. FAIRHURST: Well, I ask the question, what is the
probability that a waste package disappears the moment you put it in
there? It's zero.
MR. SAGAR: And I'm not disagreeing with that. I think you
can factor in the probability which would be the main line performance
assessment. You would have the probability. You would have even
time-dependent failure rates. You would have all sort of those things
built in and we present it to you with 246 sampled parameters and 300
other deterministic parameters, so on, so forth.
That would be presented and would be the main focus of
review. Now you start asking, well, what if the uncertainties were so
great or what if this happened, how much each one is contributing to the
risk, it's not realistic. I completely agree, it's not realistic.
MR. FAIRHURST: I'm talking about more the forum in which
this is examined, not the -- my understanding of --
MR. SAGAR: Well, there seems to be a sensitivity that if
you have presented a result which you cannot claim to be realistic, then
it should never, ever come out in public. Now, that may be true. I'm
not a lawyer and I have never, never participated in a licensing action.
So I don't know what the sociological impact of all this is.
But as an engineer, I've done it all my life.
MR. FAIRHURST: Sure, now I understand. But wait till you
talk with those other engineers, right?
MR. SAGAR: Right. Well, the engineers talk to the public
apparently it's okay when you design a bridge or a dam to say what if,
what if the thousand year flood came, what would happen, and that's okay
to judge risk.
MR. FAIRHURST: There's about 5,000 other bridges around.
MR. SAGAR: But this being nuclear, I mean, people are extra
sensitive to that.
MR. FAIRHURST: I understand.
MR. GARRICK: Budhi? Go ahead.
MR. CAMPBELL: In the presentation that you and Norm had
given about a year ago, you talked about a number of possible risk
measurements using this technique, the importance measures, risk
achievement worth and a number of others, and those are presented as
some sort of ratio and that's the measure that you're looking at.
MR. SAGAR: That's correct.
MR. CAMPBELL: I think part of the problem is DOE is trying
to present this in terms of a dose rather than as some measure of
contribution to performance, which is really a ratio or some sort of
normalized ratio. Does that make sense?
Maybe it's a matter of how you present this rather than --
and what your measure is. It's not really dose. It's a ratio.
MR. SAGAR: Well, yes, it's a ratio and what you really want
to do is rank your subsystems or components as to which one is more
effective than the other.
But the ratios are based on the dose, expected dose you
calculated. So I don't deal in the middle step. Does that make it more
transparent or less transparent? It is the same thing. Should I always
present probability multiplied by consequence or should I say
probability is X and consequence is Y, now I'm multiplying it and this
is the answer? Does one make it better than the other?
I mean, on the one hand, we want transparency where all
steps have to be clear. On the other, we are sensitive to only
presenting certain things and hiding some others. Well, I have great
difficulty, personally, getting a balance in those two.
MR. GARRICK: One of the things that's important in what
Keith and Tim said, it seems to me, is coordination with NRR and the
getting of a consistent NRC-wide tenet of operation with respect to
And as I read the defense-in-depth letter that was developed
by the ACRS, the theme of that letter is that we ought to be able to be
much more scientific, and this is what we've been saying all along, we
ought to be able to be much more scientific about what we mean by
defense-in-depth and the role of risk assessment in that regard.
Basically, the role of risk assessment in that regard is it
gives us a great deal more insight than we perhaps previously had on
where or when defense-in-depth is appropriate.
I think that's a healthy and constructive perspective. The
words we've used in this committee are that the risk-informed approach
takes some of the mystery out of defense-in-depth and they use a
specific example of how PRA illuminates the issue of defense-in-depth
and they use the example of fires.
On the one hand, there is pretty good information and pretty
good evidence and we're able to capture the issue of the frequency of
fires as a function of location in our probability density functions
pretty darn well, but when we get into the next step of the fire,
namely, the propagation and the growth of the fire, it's much more
difficult to characterize that in what some people have, in their mind,
as what is meant by being quantitative.
But you still can. You can represent all phases of the fire
quantitatively. You just may not like the spread of the curves, the
amount of uncertainty.
So there, the whole -- the convergence of the
defense-in-depth idea is on, again, the issue of uncertainty, as
something to provide us additional assurance that where the
uncertainties are greater than we like, that we can deal with that with
the concept of defense-in-depth.
I think, however, the area where we have to be very much on
guard is in the area of our risk measures, and that's the -- there is a
substantial amount of controversy going on right now on the reactor side
in that arena.
The ACRS is advocating the elevation of core damage
frequency to the level of a bona fide safety goal. Well, the voices on
the other side are saying, wait a minute, core damage is not a measure
of risk. It doesn't measure health effects and, furthermore, you can go
to the risk assessments and find scenarios where you can decrease the
core damage frequency, but you increase the health and safety risk; so
is that a good direction for us to go.
There's a contingency of people that said no. Fortunately,
in the waste field, we are focusing on the health effects or at least
the dose to the public. So we've eliminated that dilemma.
But I think one of the things that the two groups, the NRR
and the NMSS, to respond to John Greeves and wanting advice, that we
need to be very careful about is this issue of drifting back into a
subsystem requirement state of mind.
I'm reading a sentence here in the ACRS letter and it says
for those regulatory functions that are not well suited for PRA -- and
for the life of me, I don't know what those would be -- are aware the
current capabilities of PRAs are not sufficient. We suggest that the
limits on application of defense-in-depth be placed at levels lower than
the top level safety objectives.
Now, I later find out what they mean by that, but the thing
that we need to be very much on guard for is that we don't think that we
can allocate, if you wish, these goals to lower levels, because, again,
the risk is so site-specific that what is important at a lower level in
one site will not be important at another site.
So it just simply -- -- experience tells us that concept
just simply does not work. The whole issue of risk apportionment or
risk allocation to lower levels does not work, because -- and I think
we've got classic example after example to demonstrate that.
So I think that what I would urge NMSS to do, because their
problems are quite different, is to work with NRR, but not work with
them in a follow mode. You've got to work with them in a very proactive
mode and leadership mode, because you are in a fortunate position, as
somebody already said, of not having a lot of the baggage of the old
regulations that makes it burdensome and cumbersome to move
expeditiously towards a risk-informed approach.
The waste field is there and it ought to take advantage of
that opportunity. But to also be on guard for the emergence of an
approach to defense-in-depth that doesn't really befit the spirit of a
real performance-based method of regulation.
So that's a long statement, but I think that the main point
of it is that the NRR and NMSS need to work together, but NMSS needs to
be proactive and have a leadership position with respect to how this
concept applies to materials and that you have some advantages that you
need to be aware of, that the reactor side does not in terms of the risk
measures that are being employed, and you're in, in certain respects, a
better position to implement a risk-informed approach immediately rather
But that you need to be on guard for this inertia that seems
to exist for developing lower level standards and lower level safety
goals and what have you.
MR. McCONNELL: Yes. I think we agree with basically
everything you said. I think if you look at the schedule for what we
have to do, that it's going to require us to be fairly assertive, what
we do to address this with our cousins in NRR, because we are probably
on a much shorter timeframe than what they're working toward.
And we also are keenly aware, I think everybody who has
discussed this issue within the staff, about the slippery slope that
exists out there. Once you start quantifying the risk, there's always
the next question, which says, okay, well, how much performance from the
individual barrier is sufficient, and I think there is an inherent
desire to answer that question.
But when we start answering that question, even in a review
plan, we get to the point where we're, in essence, defining subsystem
MR. GARRICK: The only answer that makes sense to that
question is the impact on the measure against which you're trying to
protect the health and safety of the public.
MR. McCONNELL: As you indicated, I don't think we want to
start allocating performance to individual barriers.
MR. GARRICK: Right.
MR. EISENBERG: Could I say something?
MR. GARRICK: I always get Norm up front. Yes.
MR. EISENBERG: Actually, I would like to respond to
something Dr. Fairhurst said with regard to whether or not the analysis
was realistic or not. As Budhi indicates, the importance analysis is
not and is not intended to be a realistic analysis.
However, it may be able to shed some insights onto this
issue of defense-in-depth. Let me just expound a little bit on what
Sorenson said in his paper.
Even with the rationalist approach, what he focused on was
that defense-in-depth was, in a risk-informed regulatory environment,
was a way to deal with uncertainty and obviously we're talking about how
to deal with the residual uncertainty.
Now, a problem that is faced by both the reactor regulation
people and by repository regulation people is that we know that our
analyses, even if they're the best we can make them, that they have
And the uncertainties, unfortunately -- and, you know, we
try very hard, I think, to follow Dr. Garrick's advice and say -- and
try to represent the uncertainties in the analysis. We try to get a
realistic appraisal of what the parameter distributions are and we try
to represent other types of uncertainties in the analysis.
But even though we try to do that, everybody knows that the
analyses have residual uncertainties. Some of those uncertainties
relate to completeness, some of those uncertainties relate to whether or
not the models are correct.
I think examples in the reactor business are that, for
example, many of the PRAs do not have fire risk assessments, they do not
have shutdown risk assessments, they do not have seismic risk
So I think you always have to be careful in this arena where
you're basing your regulatory decisions on a risk that -- you must
remember that there are uncertainties that we have tried to characterize
and quantify in the analysis, but there may also be other uncertainties
that are not quantified or analyzed.
And one of the reasons that we went into this importance
analysis is that it is a way not necessarily of knowing what those are
or how big they are, but it gives you some concept of how bad things
could be, and, therefore, gives you a benchmark, if you will, as to how
important it is to -- and this is what Tim said in his talk.
The support for a particular part of the system or for a
particular barrier should be dependent on the role that it plays in
providing the desired performance. And this is a way to get at that.
So I'm not sure that this is especially inimical to having a
risk-informed approach for doing things in that context.
It's just another way to get at, if you will, some of the
MR. HORNBERGER: If I could, I'd like to comment -- well,
partly in response to Norm, but also to be responsive to the question
that John Greeves posed to get feedback.
To tell you the truth, I have always been uncomfortable with
the neutralization of barrier approach, for specifically reasons that
Charles and John hint at, but I recognize that it's one way, as Norm
just explained, to perhaps get some information and that's what we're
But I guess what I would urge the staff to do is to remain
open to other approaches, as I know they are, and, in particular, I know
Stan Kaplan has made some suggestions for presentations and, to me,
another way to look at it would be to look at some of the measures that
Stan has suggested for looking at alternative designs, which is a way,
perhaps in a more transparent way, to evaluate the importance of various
barriers to the performance of repository, in a way that doesn't assume
that there aren't any canisters there from time zero.
MR. McCONNELL: Sets the stage for this afternoon's
discussion, I guess.
MR. GARRICK: Right.
MR. McCONNELL: Or maybe later this morning.
MR. FAIRHURST: The waste package may be not entirely
unique, but a little bit different in that it's containing waste which
is declining, decaying in time, and you may want to say -- to give the
public a better feel. If we neutralize these at time zero, this is what
happens; if we do it at 2,000 years, this is what happens, at 4,000,
Other barriers are virtually time-independent. The time to
the unsaturated zone and through the -- that particular one is perhaps a
different in how you deal with it.
MR. McCONNELL: One other aspect that we found in our public
meetings is it's one thing for us to talk amongst our scientist engineer
selves on this particular issue, but it's another thing to talk to the
public and communicating with the public is difficult, particularly when
we talk complex issues, like neutralization of components of barriers.
I think they kind of go blank at that point.
MR. WYMER: I have one comment that relates to all this, but
it's certainly not as global as what I've just been hearing discussed
and it sort of relates to the hierarchy of barriers.
When you look at the system multiple barriers, you say,
well, here's the big one that really cuts out the main part of the dose
and there are other things that cut out lesser parts. Very soon, you
get down to a barrier that, while it may be a very effective barrier, in
the face of all these other barriers, it's inconsequential.
So there is a gradation of contributions of barriers, going
to Norm's statement, there are uncertainties in these systems. So the
question is how do you determine, where do you determine the cutoff is
in where you consider the utility of multiple barriers.
You can at least speculate that there may be an unforeseen
and major failure of one of the barriers that you're really relying on,
but it just doesn't work, for some reason. I know that's unlikely, but
speculate for a moment. Then you can drop back and say, well, there's
another barrier down here which really only decreased the very small
dose that you got because the barrier was assumed to work, it didn't --
it wasn't apparent.
But if you remove this other barrier, then it could be the
800-pound gorilla that really controlled the dose. So there is a
question of how deep do you go in deciding where you stop considering
And I don't know the answer, but I'd like to hear a little
bit of discussion on it.
MR. McCONNELL: We probably have to answers to that
question. The first answer is that we'd probably require DOE to develop
that hierarchy about which barriers are most important, and then go down
But, also, and Tim can elaborate on this, in the rule, we do
indicate or define what a barrier is and basically it has significant
capability to, I think, aid in isolation of waste. Is that correct,
Tim? Are they there?
MR. McCARTIN: Right. The emphasis is on the capability of
I guess one could make an argument, let's say you have no
juvenile failures and no corrosion of the waste package, nothing gets
out. So obviously the only thing contributing to keeping the dose low
in our performance assessment is the waste package.
However, multiple barriers is looking at the capability of
the barrier. And I might go to the alluvium and look at, it has
tremendous retardation capability. Because there was no radionuclide to
get there in 10,000 years, it didn't have to serve that function, but
the capability still exists. That's why we wrote --
MR. WYMER: So it's a capability, and not the contribution.
Is that what you just said?
MR. McCONNELL: That's what is in Part 63.
MR. WYMER: And that's very good.
MR. McCONNELL: But there are probably diverging views on
MR. McCARTIN: There are different ways to demonstrate that
capability. For example, in the case I gave, where -- let's assume
there's no container failures for 10,000 years. I may do an analysis
such as I failed some of the containers to see, okay, what happens to
the dose due to the alluvium, or, conversely, I just show I've done the
measurements, I've done the analysis, the laboratory work to
characterize the site, and the retardation in the alluvium is X.
That's why it's a barrier, is that retardation. I don't
necessarily have to stress it. Maybe I do a calculation past 10,000
years to show how it does it, but you don't necessarily have to. You
aren't required to do that.
There are multiple ways to talk to the capability.
MR. WYMER: Okay.
MR. McCONNELL: Okay.
MR. CRAGNOLINO: Since the waste package was mentioned by
Tim, I think that this could be a good example of an approach that can
be adopted to solve this issue.
I showed yesterday a plot in which you have three different
materials, 825, 625, and alloy-22. For this case, you have different
response, all realistic cases.
You have an initial failure for 825 and 625 due to localized
corrosion and you have later on a period, which you don't see too much,
failure, and the uniform corrosion is for 825 and 625.
For C-22, you don't have localized corrosion. You have only
one process. I think that every barrier should have properties that you
MR. GARRICK: You're right on target, yes, and that's what
we've been pushing for, is more engineering-oriented information that we
can trade off and see.
MR. GREEVES: Just a question, and this is a philosophy
issue, in part. What is your view on institutional control? We can't
rely on it for meeting the requirements of the regulation, but is it
part of the defense-in-depth strategy? I mean, the realistic issue is a
site like this, as long as society sticks around, is going to be
controlled. Is that a part of the --
MR. HORNBERGER: You're right. It's a philosophical issue.
My own view and what I've tried to stress is using the use of the term
multiple barriers rather than defense-in-depth, because I think multiple
barriers is very clear-cut, we understand what we're doing.
This doesn't mean that we don't have institutional control,
it doesn't mean that we don't take all sorts of other measures, but
defense-in-depth, even as Jack Sorenson found out, is a concept that's
pretty fuzzy around the edges, whereas multiple barriers is pretty
MR. GREEVES: I'm reading the Commission's paper and the
first sentence leads, successive compensatory measures, and compensatory
measures includes actions by man.
MR. HORNBERGER: It's fine. So if you want to have it that
way and if you want to define it that way and you ask me should we have
institutional controls, of course, we should have institutional control
and we will, as you pointed out, for as long as it certainly makes
How one builds that into an analysis, particularly over
10,000 years, the argument has always been that we can't take credit for
MR. GREEVES: And for meeting compliance criteria, I think
that makes sense. But in answering the question, do you have
defense-in-depth, I raise the question, is it legitimate to say that's a
piece of defense-in-depth.
MR. FAIRHURST: If you have a license application in at a
certain time, I think all you can put in is what you can guarantee --
not guarantee, but what you can say scientifically at that time.
MR. GREEVES: I'm asking a different question.
MR. FAIRHURST: I know you are. But what I'm saying is
that, for example, not only for institutional controls, but the whole
advance of technology, the whole ability to improve or change over that
period, and that's part of a broader spectrum that I do not think you
can take -- you can't go with a license application and say I know there
will be improvements in technology; therefore, it's going to be safer
than I've got.
And in the same way, you can't guarantee institutional
controls and so you can't put any -- you can say it cannot be a part --
the majority -- I much prefer to define it as multiple barriers, because
then I know what it applies to, it's a system that I have designed.
MR. McCARTIN: From a Part 63 standpoint, I think we would
say that the last line of defense and the overall defense-in-depth
strategy for the Commission and for the rule is that they have to have a
plan for long-term oversight. And you're right, we can't count on it in
our performance assessment. But there is, in the regulation, a
requirement that they will have oversight for that site out into the
And you're right, you can't quantify it, but in terms of a
defense-in-depth philosophy, I think it is one of those measures.
I agree, also, that you can't take credit for it, but it is
why that requirement is there; it is that last line of defense.
MR. GARRICK: The problem you mentioned is probably far more
serious with respect to the stewardship issue of the cleanup of the
national laboratories than it is for the administrative control
associated with stuff that's a thousand meters under the ground and
designed very well to stay there and be relatively undisturbed.
So I think it really has to be put in perspective. It's
part of it, but the design philosophy, the safety design philosophy in
the nuclear business has always been, as it is in most systems, to move
in the direction of decreasing dependence on administrative process.
MR. GREEVES: The staff is asking the question. We've got
this guidance from the Commission that says successive compensatory
measures. Engineer scientists like to talk about barriers, that's what
they understand, and the staff is asking the question that can we, in
addition, not for purposes of doing a performance assessment for the 25
millirem standard, but a separate provision in the rule calls for
MR. WYMER: I think institutional controls are a part of
MR. GREEVES: Tim just articulated that we, at the present
time, are identifying that that's a piece of it. It's not everything.
MR. WYMER: The fact that it's time-dependent, it doesn't
really wash, I mean, it doesn't make any difference. If it helps for
the 50 years pre-closure, why, then you have some defense-in-depth
through the institutional controls.
MR. GREEVES: I would just invite you to think about this
process, because we don't want to give them an answer that you will --
MR. HORNBERGER: I think it's fine. The difficulty is --
and if you talk to Jack Sorenson, Jack Sorenson and I have had several
conversations, and the difficulty that exists right now is that you add
confusion to terms when you use them to be sort of all-encompassing,
because what happens then, it means -- if it means everything, then it
really is a nothing term. It doesn't define anything, and that's the
difficulty you run into.
So if everything is defense-in-depth, if pre-closure
operational procedures are part of defense-in-depth, if warning flags,
if a fence, on and on and on, if it's all defense-in-depth, should we do
it all? Of course we're going to do it all, of course we are.
So if you want to call that defense-in-depth, that's fine,
but my only view is you're just muddying the waters.
MR. FAIRHURST: I agree. I agree, yes.
MR. GARRICK: And the transition has been from the more
mysterious defense-in-depth way of thinking to hopefully moving in the
direction of the quantification of uncertainty, and that's the healthy
aspect of what's going on here and that's why I think the ACRS points to
the uncertainty quantification exercise as the mechanism for indicating
when additional actions are necessary to deal with those uncertainties
that they choose to call defense-in-depth.
MR. FAIRHURST: Somewhat as an aside, I was recently
involved in a discussion in Europe about institutional controls and it
was when DOE decided to say they would maybe keep the repository open
for 300 years rather than 100, which threw them into total confusion,
because they said that they, for a long time, because they have longer
institutions, they had a mind set that 300 years was not a bad number
and they thought the US was being far too severe by limiting to 100.
Then they said they saw what happened to the control of
nuclear materials in the Soviet Union and the breakdown and the lack of
institutional control there, and they said, my god, we are pulling back,
we thought 100 years was maybe too long, and now we say you're going to
go to 300.
So you can get into a debate on that thing, but the
uncertainties are far more than any waste package failure.
It's a little bit of a red herring.
MR. GREEVES: I would just invite you to think about the
question I asked, because in an operating facility, a fence is a
barrier, but we also require surveys. And I can give you examples where
the licensee went out and made surveys and found out that he was doing
the wrong thing.
It's not a fence, it's not a container, it's a human
activity and you've made a change and it's kind of a safety network, a
defense-in-depth process that helped the safety, he was able to tighten
up his facility.
MR. FAIRHURST: You do what you can, but don't take credit
MR. GREEVES: I'd just invite you to -- because we --
MR. HORNBERGER: We haven't issued an answer on these
questions. We have thought about it and we will continue to think about
it. So your point is well taken. It's not a very clear-cut issue.
MR. GARRICK: Tim.
MR. McCARTIN: I guess one thing I'd like to add would be
that our requirement is for local barriers. We have no requirement for
defense-in-depth. It's just the Commission has a philosophy of
defense-in-depth and I guess that's where maybe we need to make that
clearer somewhere in the SOC. But I think the long-term oversight, just
as with emergency planning for operations of all nuclear facilities, I
think the Commission considers that part of defense-in-depth.
That you have all these measures in place, these barriers,
but then you also have emergency planning for things that, gee, they may
not work the way we hope, and I think that that all encompasses the
defense-in-depth philosophy. But our requirement is for multiple
Maybe we need to make that clear in the SOC and talk to
MR. GARRICK: All right. Thank you. Thank you very much.
I think that concludes the discussion on defense-in-depth, which is --
MR. FAIRHURST: For now.
MR. GARRICK: For now.
MR. FAIRHURST: Gone deep enough, right?
MR. GARRICK: And I'm sure it will reappear.
What I would like to do now is talk a little bit about what
we want to do the rest of the morning and my suggestion is that we start
it off by taking a break.
But before we take the break and when we come back, I think
that I would like the committee to talk a little bit about whether or
not what we've heard the last couple of days, if there's any action that
we need to take as a result of it, and depending on that discussion, we
may want to revisit the agendas for the July and September meeting and
talk about them a little more deliberately with respect to products that
we ought to be generating.
Also, we need to make sure that our planning with respect to
the Commission meeting is -- we advance it as far as we can for this
So I think this will terminate, for the most part, the
discussion of the presentations and certainly does the presentations
themselves, except to the extent that we might want to discuss a little
bit whether or not we want to generate something as a result of it.
So with that, let's take a 15-minute break.
[Whereupon, at 10:45 a.m., the meeting was concluded.]
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