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ACRS/ACNW Joint Subcommittee - May 4, 2000

UNITED STATES OF AMERICA
NUCLEAR REGULATORY COMMISSION

***
MEETING: ACRS/ACNW JOINT SUBCOMMITTEE

U.S. NRC
Two White Flint North, Room T2-B3
11545 Rockville Pike
Rockville, MD

Thursday, May 4, 2000

The committee met, pursuant to notice, at 8:30
a.m.
MEMBERS PRESENT:
JOHN GARRICK, ACRS Chairman
THOMAS KRESS, ACRS Co-Chairman
GEORGE APOSTOLAKIS, ACRS, Member
GEORGE HORNBERGER, ACRS, Member. C O N T E N T S
PAGE ITEM
Introduction 3
Overview: Risk-Informing NMSS Activities 4
Status of SECY-99-100 Efforts: Training,
Workshop, Criteria, Safety Goals 33
A Process for Risk-Informed Regulation of
Activities 109
PRA for Dry Cask Storage 119
Nuclear Byproduct Materials Risk Review 201
Matrix Summary of Risk Assessment Results
for Byproducts Materials Activities 201
Proposed Rule for Domestic Licensing of Special
Nuclear Material 236
. P R O C E E D I N G S
[8:30 a.m.]
DR. GARRICK: Good morning. Our meeting will now
come to order. This is a meeting of the joint subcommittee
of the Advisory Committee on Reactor Safeguards and the
Advisory Committee on Nuclear Waste. I'm John Garrick, co-
chairman of the joint subcommittee. On my right is Tom
Kress, also co-chairman of the committee. Joint
subcommittee members in attendance are George Apostolakis of
the Advisory Committee on Reactor Safeguards and George
Hornberger of the Advisory Committee on Nuclear Waste.
The purpose of this meeting is for the joint
subcommittee to discuss the development of risk-informed
regulation in the Office of Nuclear Material Safety and
Safeguards, including risk-informing fuel cycle programs,
integrated safety assessments, byproduct material risk
analysis, dry cask storage risk analysis, the results of a
public workshop on the use of risk information in regulating
the use of nuclear materials and related matters. Sounds
like a busy day.
The subcommittee will gather information; analyze
relevant issues and facts; and formulate some positions and
actions as appropriate for deliberation by the full
committees. Richard Major is the designated Federal
official for the initial portion of this meeting. The rules
for participation in today's meeting have been announced as
part of the notice of this previously published in the
Federal Register, part of the notice previously published in
the Federal Register. A transcript of the meeting is being
kept, and it's requested that speakers identify themselves,
speak with clarity and volume so that they can be heard.
We've received no written comments from members of
the public, but we have received one request from Robert
Bernero for time to make an oral statement, and right now,
it's hopeful that we can fit that in right after our second
presentation and perhaps just before or just after the
break.
Our first speaker will be Marty Virgilio, deputy
director of the Office of Nuclear Materials Safety and
Safeguards, and unless there are some comments or questions
from the members, I think we'll proceed, Marty, and let you
take the floor.
DR. VIRGILIO: Thank you; good morning. I am
Marty Virgilio, for the record, deputy director of our
Office of Nuclear Materials Safety and Safeguards, and I'd
like to start with a thank you to the committee members for
taking the time to meet with us today. I look forward to a
productive exchange of ideas.
With me today, I have John Flack, who will be
speaking to you next. You may know John from his
responsibilities in the Office of Research, but John has
been working with us for the last several months heading up
this risk group that we have formed in NMSS. Also today,
you'll have a chance to meet some of the members of the risk
group. You may have met some of them before in the other
responsibilities: Stacy Rosenberg will be with us today.
Stacy has been a risk expert in the office of NRR, and I
believe that at one point in time, that she may have briefed
you on a risk assessment that she was responsible for on
Kiwi Dam, where we were looking at the safety requirements
necessary to ensure protection for the Oconee Nuclear Power
Station. Stacy was responsible for that effort.
We also have Dennis Damon with us today. Dennis
is going to be talking us a little bit later about fuel
cycle facility safety and the ISAs that are being performed
or being required there as a part of our new Part 70. Jim
Smith is here with us today. Jim is also a member of the
group. He's our medical and industrial link, and Christiana
Lew, which I know you've met and had interactions with
Christiana over the high-level waste program.
We also have Alan Rubin with us today. Alan is
from the Office of Research. He will talk to us today about
the PRA that Research is doing to help us in understanding
some of the issues surrounding high level waste storage, and
Betsy Ulrich will be coming down from region 1. Betsy is
not here yet but will be making a presentation to you later
this morning or early this afternoon on a material risk
study that we had done.
What we have in store for you all today is an
exchange on the overview of our program and the status of
our current activities, and then, we'll have the individual
presentations on the cask storage, on Part 70, the fuel
cycle facility requirements and the ISAs and also on the by-
product materials risk review study. If I can have the
first slide, please. Next slide, please.
Just by way of background, and I know you're all
familiar with this, but I thought it just again for the
record, and maybe the audience, going through the
chronology; we started, I think, in earnest looking at risk-
informing the waste and material activities in 1997 with a
commission paper where we laid out some ideas as to
direction and received some feedback from the Commission on
our approach. And in March of 1999, we put forward a
Commission paper, SECY 99-100, that provided a lot more
detail on our proposed approach, areas where we were
considering risk-informing our programs and activities.
The Commission responded to that SECY paper in
June of 1999 with an SRM and provided more direction to us,
additional ideas and thoughts about which directions that we
ought to be proceeding in, and in July of 1999, we
established a task force to move this effort forward. On
the next page, if I could have the next slide, please, just
going back to SECY 99-100, we had a number of
recommendations in that, the first being that we proceed to
implement a five-step process, and I've got another slide in
a few seconds I'll show you on that five-step process and
that we continue to implement our approaches for addressing
risk management issues, our ongoing activities and that the
Commission approve the formation of a joint subcommittee
that would help us with constructive criticism and peer
review of our ongoing activities and ideas for directions in
the future.
On the next slide, you can see the SRM, and
basically, the Commission accepted the proposal that we laid
out, those three ideas I put on the last slide, and in
addition provided some additional guidance to us. They
asked us to develop materials safety goals; they asked us to
make sure that we were using an enhanced participatory
process to develop the goals and include within the goals
the avoidance of property damage. They asked us to consider
critical groups and whether critical groups could be defined
like we have done in the high-level waste forum for other
activities in assessing risk and managing risk.
DR. APOSTOLAKIS: What is the logic behind
avoiding property damage here and not including land
contamination for reactors?
DR. VIRGILIO: None that I -- you know, and I --
it's a good question as to where we --
DR. KRESS: I would guess, George, that they're
focusing on the Yucca Mountain type issue or -- you'd
probably only get property damage as a real consequence in
the accidents. That would be my guess.
DR. VIRGILIO: Tom, as we go through and look at
some of the material activities that we have and some of the
issues that we're dealing with today, we're not only dealing
with radiological contamination, but if you think about
issues that we're dealing with like Atlas, Moab, we're also
dealing now with more environmental issues in the waste and
material arena than on the reactor issue, and I think this
was on the Commission's mind --
DR. KRESS: Yes, I think --
DR. VIRGILIO: -- at the time that they were
generating this SRM. It was not only the repository, but I
think it was some of these other issues.
DR. KRESS: Right; it's environmental
contamination in general.
DR. VIRGILIO: The SDNP sites that we're involved
in; there are so many different issues that we're involved
in today that includes the environment and property
considerations that I think it was only logical that they
went that way. But then again, you say, well, why aren't we
going in that direction for reactors, which I think, you
know, is a little outside my scope but might be something to
consider as we move forward in that front.
DR. KRESS: I think we ought to do it.
DR. APOSTOLAKIS: Yes, but, I mean, the staff has
come back and said that they will not include it, right?
DR. KRESS: They only include it in regulatory
analysis.
DR. APOSTOLAKIS: Yes, but not part of the
quantitative --
DR. KRESS: They don't have quantitative safety
goals.
DR. APOSTOLAKIS: Yes.
DR. KRESS: There are some people I've heard say
that it's subsumed within the two goals that they have to
some extent.
DR. APOSTOLAKIS: Yes.
DR. KRESS: But I don't believe that.
DR. GARRICK: Okay.
DR. VIRGILIO: Okay; and last, they asked us to
ensure that we include the agreement state component in our
thought processes; today, we have 31 agreement states, and
there are four more eager to join the program and so --
DR. APOSTOLAKIS: On the previous slide, again, I
have another question.
DR. VIRGILIO: Sure.
DR. APOSTOLAKIS: What's a critical group?
DR. VIRGILIO: In the context of Yucca Mountain is
the best way that I can describe it --
DR. APOSTOLAKIS: Yes.
DR. VIRGILIO: -- by example is that we are
looking at the effects of the plume that could be predicted
to leave the repository; on a group -- a hypothetical group,
a farming community living within the vicinity of the
repository, and we're looking at the effects on that group.
We're looking at how much will they receive in terms of dose
as a result of hypothetical accidents that could occur at
Yucca Mountain. You could think about critical groups in
terms of transportation, another example that we haven't
gone down. This is my example, but you could think about
transporting a cask down the road and possibly having a
critical group or a target for assessing risk to the public
as a family in a car driving alongside that cask or, you
know, or somebody -- or the folks that work at the truck
stop, where the truck might stop on its route.
DR. APOSTOLAKIS: Yes.
DR. VIRGILIO: So it's hypothetical groups of
members of the public and how they might be exposed to
radiation as a result of accidents, upsets or normal
activities associated with the program.
DR. APOSTOLAKIS: Now, why don't we use the term
in reactors?
DR. KRESS: Critical groups?
DR. APOSTOLAKIS: Yes; I mean, we use the idea.
DR. KRESS: Yes, we use the idea.
DR. APOSTOLAKIS: But not -- is part of this joint
subcommittee trying -- part of the purpose of existing here
is to harmonize the terminology, perhaps? I mean, what's so
different here? I mean, you have to try a little harder, I
think, to define the critical group. There was a
controversy in that Academy report regarding what the group
is because of the huge time scales. But it would be
helpful, I think, to start using the same terms.
DR. HORNBARGER: What term is used in reactors?
DR. APOSTOLAKIS: Nothing; we just say individual
risk, societal risk.
DR. HORNBARGER: But you have to use an N
individual.
DR. APOSTOLAKIS: Yes.
DR. HORNBARGER: So it's an individual and not a
group.
DR. APOSTOLAKIS: It's not a group at this time.
DR. KRESS: It's a group averaged into --
DR. HORNBARGER: Okay; so, it's the same idea,
then.
DR. APOSTOLAKIS: Well, the way it's calculated --
DR. HORNBARGER: It's the individual; it's the
sort of average individual in a critical group.
DR. APOSTOLAKIS: Exactly.
DR. HORNBARGER: Yes.
DR. APOSTOLAKIS: Exactly; but it's supposed to
be, you know, the community surrounding the reactor, I
suppose.
DR. HORNBARGER: Yes.
DR. APOSTOLAKIS: You don't have to make any
hypothesis, because you know who they are.
DR. KRESS: Yes; it's the ones living around
the --
DR. APOSTOLAKIS: Yes.
DR. HORNBARGER: Right.
DR. APOSTOLAKIS: So either there is no --
DR. HORNBARGER: Well, you still have to make an
hypothesis, because the community can grow --
DR. KRESS: Yes.
DR. APOSTOLAKIS: That's right.
DR. HORNBARGER: -- over the lifetime of the
reactor.
DR. APOSTOLAKIS: That's right so --
DR. KRESS: That's supposed to be part of the
analysis, protecting that. But you don't have to worry
about 10,000 years either.
DR. HORNBARGER: It's a better guess.
DR. APOSTOLAKIS: Yes.
DR. VIRGILIO: Next slide, please. I think we've
covered that one.
Just to go back to SECY 99-100 for a moment, the
Commission endorsed the staff's approach to a five-step
process. Those steps really boil down to identifying the
candidate applications, where we would want to move forward
and risk-inform our programs; decide how we would then
modify our regulatory approaches; change the approaches; and
then implement the program, and in parallel with that, we
would be developing or refining the risk tools that we have
available to us through the reactor program and through our
own program activities.
If we go to the next slide, after our last
interaction, and sometime in the November time frame, you
wrote a letter to Chairman Meserve and recommended that we
do a number of things. We saw that the two key things
within your recommendations being that you asked us to
develop a set of principles and a safety goal approach for
each of the NMSS-regulated activities, and you asked us to
identify analytical methods to be applied to implement these
approaches on an application-specific basis.
If you go to the next slide, Pat, we wrote you
back in January, and we told you that we would develop
screening criteria, and here we were being or trying to be
as responsive as we could to your recommendation on a set of
principles, so this is the way we were approaching it, by
developing screening criteria for determining what we would
move forward with and risk-inform in specific applications.
We also said that we would examine experience with risk
assessment methods, measures and metrics currently being
applied. Here again, we were being responsive to your
recommendation that we look at our analytical methods.
In addition to responding to your recommendations,
we told you that we were going to move forward using the
enhanced participatory process; scheduling meetings and
workshops with interested parties and that we would begin to
develop our training program.
If you go to the next slide, please, what I want
to do is give you a little bit of status on where we are on
what we told you we were going to do. What we did is we
developed and published in the Federal Register some draft
screening criteria for identifying those areas where we
should apply risk-informed approaches. We solicited public
participation in the development of the screening criteria
and safety goals in a workshop we had just a couple weeks
ago.
We are currently in the process of examining our
methods, measures and metrics that we would apply in NMSS to
confirm that we are on the appropriate approaches, and
today, we'll share with you some of the specific
applications and some of the methods that we're using and
hopefully get some feedback from you on whether we're on
track with regard to those programs. And lastly, I think
we've made significant progress in developing our training
program.
On the next slide, I just highlight some current
activities we have ongoing a little bit outside of the scope
of what we've been corresponding with you on. We've made
some organizational changes. We've brought the risk group
that we had formulated and residing in one of our technical
divisions up to the front office, so now, the risk group
reports directly to Bill Kane and I, and we've established a
steering group, and I think you'll recognize some of the
members of the steering group. They include, within NMSS,
Don Kuhl and John Grieves and Mike Weber. And then, from
outside NMSS, Gary Hollohan, Tom King from research; Bruce
Malik from Region II and Joe Gray from OGC.
In addition to supporting Tom, we also have Joe
Murphy, who has been in and out of this process, but I think
we've got a very strong steering group now to help ensure
that we stay on track. And today, we'll talk a little bit
about some of the activities that we have ongoing, including
the ISAs for the fuel cycles; the byproduct material risk
analysis; the PRA for dry cask storage, and I understand
that the full committee got a recent briefing on
transportation and where we're going on our risk studies
there. So we didn't put it on the agenda today, but we
could come back to you again in the very near future and
give you an update on where we're going on our
transportation risk studies.
On the next slide, just highlighting that we're
increasing our interactions with the stakeholders. We had a
Commission meeting in March on the risk-informed regulatory
implementation plan. A subset of that is where are we going
in the waste and materials arenas, and we had the public
workshop in April that I mentioned earlier. And John Flack
is going to go into a lot more detail about what we heard
from the stakeholders at the public workshop and some of our
analysis of those thoughts.
John will also talk about the three-tiered
approach to training that we have, and just so you
understand just the background, we thought about it in terms
of tiers and the first tier being the managers, making sure
they had a fundamental understanding of what we were doing
and then the second tier being all the staff, all the
technical staff that we have in the waste and material
arenas, including the staff working in the regional offices
and making sure they had a basic understanding of what we
were doing in these programs and then the third tier being
more advanced training for the people who would actually be
employing these risk assessment methods and using risk
management techniques as appropriate that come out of the
analysis.
So it's a three-tiered approach, and again, John
Flack will explain that in a lot more detail.
Just to highlight and introduce what John will
talk about on the next slide is the April workshop. We had
participants from other Government agencies. We had other
representatives from all of the regulated industries; public
groups and other interested parties participating, and
transcripts are now available. We're having copies of the
transcript made so you can see that, and I think it was a
very good workshop. Everybody was well-engaged, and we got
a lot of good feedback, and John is going to share with you
specifically some of the ideas in detail.
The focus of the workshop was basically two-fold.
The first part of it was looking at the screening criteria,
and we introduced that screening criteria and took comments
on it; looked at examples. We actually asked the --
challenged the group that said not only give us comments on
the screening criteria but other examples of various --
where we should move forward independent of the screening
criteria and also pilot applications, and we'll talk a
little bit more in detail about that.
And we solicited input on development of the
safety goals. We had this laid out for a day and a half,
and quite truthfully, I thought we were going to spend most
of the time talking about the screening criteria, but when I
go back and look at the transcript, we spent most of the
time talking about the safety goals, which was very
productive. I think it was a really good meeting and a lot
of good ideas on how to proceed with a process for
developing safety goals.
DR. KRESS: When you talk about safety goals in
this arena, are you talking about some sort of risk
acceptance criteria for individual facilities?
DR. VIRGILIO: At this point, what we're doing is
trying to decide how best to attack this, and we had thought
about maybe going down seven paths consistent with some of
your guidance. We have seven programs within the NMSS waste
and material program, and I think we're refining our
thoughts on that. There may be a better approach and maybe
bringing that down to five and individually maybe working
forward in some way to define safety goals in those five
specific areas, and John will get into a lot more detail
about this but not necessarily on a facility level but
starting maybe on one area, on medical, on another area,
maybe on the facilities, on the industrial facilities and
try to define goals in each of those areas and then seeing
if we could step back and say is there an overarching goal,
you know, that would cover the five or the seven areas but
working from the bottom up, working in areas and building to
see if we can get some overarching safety goals.
DR. KRESS: On a more general level, when you say
goals, is that something to be strived for or something that
has to be met?
DR. VIRGILIO: No, we're thinking in terms of a
hierarchy of overarching goals that would then be supported
by regulations that would have to be met.
DR. KRESS: Okay.
DR. VIRGILIO: And we're also trying to make sure
we have a clear idea in our minds of how these overarching
goals fit within the context of the Commission's strategic
goals. We've got a -- I don't know if you've had a chance
to see the latest strategic goals and performance goals that
the Commission is now finalizing, but there has to be a
hierarchy, I think, between these goals, the Commission's
safety goals and performance goals and then the regulatory
requirements.
DR. KRESS: That disturbs me a little, because I
don't see the connection, frankly.
DR. VIRGILIO: And we have to make that
connection. We have to do that.
DR. APOSTOLAKIS: But if you find goals, and then,
you have regulatory criteria based on those goals that must
be met, aren't you implying that the goals are in fact
defining adequate protection?
DR. VIRGILIO: I would rather stay with the
regulations defining the adequate protection and the goals
being an overarching framework.
DR. APOSTOLAKIS: So the regulations, then, will
not be derived from the goals.
DR. VIRGILIO: The regulations have to be derived
from the goals and consistent with the goals.
DR. APOSTOLAKIS: Yes; consistent, I understand.
DR. VIRGILIO: And any new regulations --
DR. APOSTOLAKIS: You have to be careful here.
DR. VIRGILIO: Yes.
DR. APOSTOLAKIS: You know, the distinction
between goals and adequate protection.
DR. VIRGILIO: We have to be abundantly clear in
defining that, and right now, I think we've got, you know,
and we've got goals; we've got strategic goals; and we've
got regulations. And as we move forward in the waste and
material arena, it's critical to us that we understand the
linkages and relationship between those three components of
our framework.
DR. KRESS: Normally, the goals put forth in the
strategic plan are sort of a measure of how well NRC does
its job of overseeing. Now, we're talking about a
regulation that deals -- regulations that deal with the
actual design and implementation thing. It seems to me like
those are two separate things and not necessarily -- they
don't necessarily have to be related to each other at all.
DR. VIRGILIO: I would say that the goals, you
know, are the outcomes that you're trying to achieve: no
deaths; you know, no destruction of property, you know, no
loss of property. I mean, those are the goals you're trying
to achieve, and the way you achieve --
DR. KRESS: When is that applied? Over the next
year? The next 5 years or --
DR. VIRGILIO: Well, the strategic goals are meant
to be enduring. If you think about the Commission's
strategic goals, they're meant to be long-lasting, enduring
goals.
DR. KRESS: No deaths forever.
DR. VIRGILIO: Right.
DR. KRESS: Well --
DR. VIRGILIO: No deaths.
The performance goals that they have in that same
book are meant to be 5-year goals. They're meant to be --
let's see how we're going to do for the next 5 years in
meeting those overarching, enduring requirements. And then,
I see the regulations as being the mechanisms, you know, the
requirements that we're going to impose on the regulated
communities for meeting, you know, to help ensure that we
achieve those outcomes.
DR. KRESS: Yes; well, that's what bothers me,
because your regulations are sort of one-time things. These
goals are going to be re-established year after year after
year. Are you going to change the regulations to meet the
new goals, or are you going to set up your regulations based
on another set of criteria and then worry about the goals
when you talk about inspection, operations and other things?
You see, that's the connection that bothers me.
DR. APOSTOLAKIS: It's not clear to me at all what
the role of the goals ought to be in the regulation, because
the regulations, really, are dealing with adequate
protection.
DR. KRESS: That's the other thing that bothers
me, absolutely, George.
DR. APOSTOLAKIS: I mean, if you go to reactors,
and it takes even at 10-4, which is a subsidiary goal for
core damage frequency --
DR. VIRGILIO: Right.
DR. APOSTOLAKIS: -- I don't think you will find
any regulation that is derived from that.
DR. KRESS: Except the backfit rule.
DR. APOSTOLAKIS: Well, then, there's one.
DR. KRESS: But, you know, that's a special.
DR. APOSTOLAKIS: And we have plants right now
that have CDF above the goal, and they're allowed to
operate. So I think that there is a real issue here, the
distinction between goals and adequate protection, and there
has been reluctance to define adequate protection
quantitatively, not only from you, or I don't even know
whether you are objecting to it, but in the reactor arena,
we were told that they would rather stay away from it,
because adequate protection is not just a number. It's the
result of a whole process, where the numbers are only part
of the process.
But I think there is a real issue there: how do
you interpret these defined criteria and quantities.
DR. GARRICK: But this is an old issue, George.
DR. APOSTOLAKIS: Yes.
DR. GARRICK: I'm looking at a SECY 89-102 written
in 1990, and it's pretty clear on its distinction between
adequate protection and goals. It says the Commission
believes that adequate protection is a case-by-case
finding --
DR. APOSTOLAKIS: Yes.
DR. GARRICK: -- based on evaluating a plant and
site combination and considering the body of our
regulations.
DR. APOSTOLAKIS: Right.
DR. GARRICK: Safety goals are to be used in a
more generic sense and not to make specific licensing
decisions.
DR. APOSTOLAKIS: Yes; but that was in 1989.
DR. GARRICK: Yes.
DR. APOSTOLAKIS: Now, we want to use the goals on
a plant-specific basis.
DR. KRESS: To risk-inform the --
DR. APOSTOLAKIS: Which would upset this, I mean,
it would change that.
DR. KRESS: Yes; I think that would upset that
concept.
DR. APOSTOLAKIS: But the question is how do you
use it? If you adjust the goal rather than the definition
of adequate protection; I mean, they're two different
things.
So you're going to have the same problem here, I
think.
DR. VIRGILIO: And this was discussed; you can see
in the transcript a number of the stakeholders raised this
issue of the relationship between the goals and the
regulations, and I think, yes, we have a challenge.
On the next slide, John will go into a lot more
detail, but I just wanted to sort of ground you at a fairly
high level as to what were some of the recommendations we
got from the participants at the workshop, and basically,
they had a number of comments with respect to the screening
criteria. There was, I think, a very strong consensus to
pursue safety goals and to do it as a series, not to try to
start with one single goal but to work down parallel paths
looking at the groups of activities that we do and see if we
could establish goals for individual groups first.
If you go to the next slide, the participants also
recommended that we summarize the results --
DR. APOSTOLAKIS: Excuse me again. Let me
understand the criteria; I'm sorry.
DR. VIRGILIO: Okay.
DR. APOSTOLAKIS: The criteria will be used how?
DR. VIRGILIO: The criteria that we put out at the
workshop --
DR. APOSTOLAKIS: Yes.
DR. VIRGILIO: Actually, we put a Federal Register
out first and then discussed at the workshop would be used
to identify new areas where we would move forward to risk-
inform. That was the purpose of the criteria.
DR. APOSTOLAKIS: Oh, oh, oh, oh, oh. That's
different.
DR. VIRGILIO: Why would you go about risk-
informing a new activity or an existing activity? And so,
we laid out a number of criteria that one would have to meet
in order to decide. And we took this from your
recommendations on principles.
DR. APOSTOLAKIS: Yes.
DR. VIRGILIO: For how do you go about approaching
risk-informing your program? You suggested that we define
some principles. And so we, instead of calling it
principles, we called it this criteria and screening
criteria.
DR. APOSTOLAKIS: So the criteria are not to be
used to identify unacceptable risks.
DR. VIRGILIO: No, sir; it was strictly to say
that this was an area where it was ripe for a risk-informed
approach, and so, we would look at it using this screening
criteria.
DR. APOSTOLAKIS: Another dream crushed by
reality. I thought you were going to define that, which
would have been a definition, a semi-definition of adequate
protection.
DR. VIRGILIO: Not yet.
DR. APOSTOLAKIS: Not yet; right.
DR. KRESS: They do have what they call
quantitative acceptance criteria in this document here,
which is a good step in the right direction.
DR. APOSTOLAKIS: Okay.
DR. VIRGILIO: Other participant recommendations
are just to summarize the results and inform the Commission
and hold more workshops. There was a desire on a number of
the stakeholders to get out and talk -- and we're talking
about regional areas, not necessarily NRC regional areas but
to get some more local input on the development of the
goals, local values, local desires.
There was a desire that we continue to work in a -
- with the group that we had or similar groups to develop
the safety goals through a consensus process, and there was
also, I think, a general agreement that we can develop
safety goals in parallel with continuing to risk-inform our
processes, not that we have to have the goals first.
That pretty much summarizes what I wanted to tell
you. If you have any additional questions on my
presentation, I'd be happy to take them now. John Flack is
going to provide a lot more detail on the training program,
the workshop recommendations, and John will actually talk as
well about some of our next steps: where do we go from
here? And any questions for me before I turn it over to
John?
DR. KRESS: Yes; on your concept of having several
groups of activities, each of which would have its own
safety goal, do you have some overriding principle that
would integrate those and make them all consistent? And
what I have in mind there is some sort of cost-benefit.
Here's this activity. It has some assessed benefit to
society. Therefore, we're willing to accept some cost of
having an accident due to that as a result, and maybe that
cost versus benefit could be the same number for each of the
activities, and since you would have different benefits, you
would have different costs, which would lead to different
acceptance criteria.
Do you have some sort of overriding principle like
that that you're trying to use?
DR. VIRGILIO: Not yet, but I think, you know, we
want to go to some overarching principle that would if not
provide consistency provide harmony or at least a logical
approach to looking at each of the five or seven areas that
we proceed down. I think we have to do that, but we haven't
thought through to the point of on what basis would you
establish that overarching view?
DR. KRESS: Well, I think you have to have
something, because you can't -- I mean, it's --
DR. VIRGILIO: Yes.
DR. KRESS: -- it's going to be incoherent if you
just pick each one out of the air. There needs to be
something to tie them together.
DR. VIRGILIO: And we also -- and I know the
Commission has given us some guidance in this area, but we
also want to look across at the reactor population, too, and
make sure that there is some logic to what we're doing vis-
a-vis what they're doing in terms of safety goals as well.
DR. KRESS: Well, they don't have this overriding
principle there either, unfortunately. It's something we
called for, but it doesn't exist. I mean, if you looked at
the prompt fatality and the latent fatality and the non-
existent land contamination and other societal risks,
there's no overriding integrating factor for those.
DR. VIRGILIO: While we believe at this point
starting from the bottom up, working in these areas would be
helpful, we all, I think, agree that that's what we need:
an overarching principle that would tie this together or a
framework that would tie this together so that logically,
you could look across the entire scope of our activities and
say --
DR. KRESS: But each one of them has a --
DR. VIRGILIO: It fits. It fits within a
framework.
DR. GARRICK: Tom, you don't think the qualitative
statements that preamble the safety goals are in the
category that you're talking about?
DR. KRESS: In a sense, when you say small
increase over --
DR. GARRICK: Yes.
DR. KRESS: -- existing risk, that is a type of --
DR. GARRICK: Right.
DR. KRESS: -- of thing, but those two are
inconsistent, because what happens is only one of the goals,
almost 90 percent of the time, controls because they're on
an inconsistent basis. They're not tied together in a
sense.
DR. VIRGILIO: Right .
DR. KRESS: For example, why should the safety of
nuclear power be tied to automobile accident deaths? I
mean, that doesn't make any sense at all to me, and that's
basically what it is: it's tied to the automobile accident
deaths. But why? There's no reason for that. So there's
no real --
DR. APOSTOLAKIS: These are policy issues, Tom.
Why should there be a reason?
DR. KRESS: Because you have to have these
acceptance criteria before you can risk-inform, and you've
got to start somewhere.
DR. APOSTOLAKIS: Yes.
DR. KRESS: And if you just pick values out of the
air, you're going to end up with an incoherence in the
system. You know, it may not be a bad incoherence, because
you could look at each group separately but --
DR. APOSTOLAKIS: But that will be a societal
incoherence.
DR. KRESS: It's a societal issue.
DR. APOSTOLAKIS: But not the Nuclear Regulatory
Commission incoherence.
DR. KRESS: Oh, yes, but society is not going to
come knocking on your door and say here's what we want. The
Nuclear Regulatory Commission has to develop these itself
somehow. Nobody is going to come and hand them to you?
DR. APOSTOLAKIS: No, but the one-tenth of 1
percent is clearly a policy issue.
DR. KRESS: Sure.
DR. APOSTOLAKIS: And it can be a logical one.
DR. KRESS: These are all policy issues.
DR. APOSTOLAKIS: Yes.
DR. KRESS: But what I'm saying, there's a need
for a coherent basis for such policy issues.
DR. GARRICK: But the one-tenth of 1 percent could
be viewed as an interpretation of what is meant by the
qualitative overarching.
DR. APOSTOLAKIS: Yes, that's what I'm saying.
DR. GARRICK: The goal that -- yes.
DR. APOSTOLAKIS: I mean, Tom, you asked what is
the reason behind it? Well, there is no reason. There is
no logic. I mean, this is it. All we want is these risks
from these technologies to be lower.
DR. KRESS: But there could be some logic is what
I'm saying. That's my problem. And the logic could be
we're willing to accept so many deaths, which means so much
money and multiplied by money per death for automobiles just
because it has certain benefits to society. You can
quantify that benefit to some extent.
We ought to be able to say what's the benefit of
nuclear power to society? And we ought to be able to accept
the same costs, that is, the same number of deaths at the
same frequency. And that's an overriding principle that
just doesn't seem to be evident anywhere in these
regulations.
DR. APOSTOLAKIS: Well, but then, you would run
into other problems.
DR. KRESS: Of course you've got the problems, but
you --
DR. APOSTOLAKIS: The threat element of risk; the
catastrophic potential.
DR. KRESS: Of course, you've got to -- we've got
to think about those things and factor them into your
decision in some way.
DR. HORNBARGER: Your argument is basically one of
risk harmonization in the jargon?
DR. KRESS: Yes; that would -- it could be called
that, yes.
DR. HORNBARGER: I mean, we would prefer to see
NRC regulations risk-informed the same way that EPA
regulations or Department of Transportation regulations, and
they'd all be based on how many, so many thousands of
dollars per statistical death.
DR. KRESS: Something like that, yes. You know,
you need some overriding principle that --
DR. APOSTOLAKIS: That's difficult to defend, yes.
DR. KRESS: Anyway, it's just a thought.
DR. VIRGILIO: John?
DR. FLACK: Okay.
DR. APOSTOLAKIS: No high-tech for you, huh?
[Laughter.]
DR. FLACK: Good morning; I am John Flack, the
risk task force leader. The risk group in NMSS is a group
that acts as a focal point of all risk-informing activities
that are going on in the office, and so, I have headed that
group up now for the past 3 months, and today, as Marty had
mentioned, I plan to cover two areas. One is the training
that is being developed for the office to bring them up to
speed in using risk concepts, and the second is to provide
you with an overview of the feedback from the public
workshop in the two areas; the screening criteria that was
sent out for distribution as part of the Federal Register
notice and the entertainment of potential safety goals for
nuclear materials and disposal of nuclear waste.
So moving on to the first topic, which is
training, as was mentioned earlier by Marty, we plan to use
a three-tier approach to train the office on risk, risk
concepts. The first year is a management and supervisory
level of training program that was really a roll-up from
tier two, which is being developed as a pilot, and we expect
to exercise that pilot this fiscal year, and I'll go into
the outline of what we're following on that pilot program.
And then, there's tier three, which is really targeting
those that are specialists in risk, who use risk on a day-
to-day activity, and some of these courses would be given
in-house, and some would be taken through other agencies,
and we're developing a list of those courses.
There's two things that need to be considered
while we're developing the training program, and one is the
fact that we also, and NMSS also has regional staff that we
need to bring in for training to make sure that it's
properly implemented risk concepts, and secondly, we need to
think about the agreement states, and one of the issues that
you'll see that came out of the workshop is that if we're
moving in a risk-informed direction, how do we train those
that are out there in the agreement states as well with
their limited amount of resources? So these are two things
we need to consider during development of the program.
Now, with respect to laying out the program for
training, I kind of followed the Farman approach. Richard
Farman used a concept when he taught students about physics;
he said first, you tell them why they need to know it, and
then, you tell them what they need to know, and then, you
let them determine for themselves how to do it. Well, we do
all three here, though. The approach that was laid out was
we would go through first explaining why we need to use risk
up front; why it's important to use it and why the
Commission has considered it to be important and then go
into the methodologies: what are the methods that we would
use to carry out this concept of using risk? And then,
finally, how it's applied through application, specific
applications as examples.
So that's the kind of thinking that when we laid
out the training program.
And as you can see, in the why of why we are using
risk, it's interesting to note that the first topic of
discussion in the introduction of that area is adequate
protection and safety goals and why they are different in
that regards based on an historical perspective as well as
where we're trying to blend the two today; it was
interesting to think about in that context; but basically,
from where we have been, safety goals, trying to be
something we aspire to which involves performance as well as
defense-in-depth that has already been instituted at the
sites to adequate protection as generally defined in the
strategic plan as meeting the bulk of the regulations.
So just getting that out as the differences in
concepts to the students and how we are trying to blend the
to understand one with regards together is something that
really should be discussed up front.
DR. KRESS: When do you define adequate protection
as meeting the bulk of the regulations? And then, you're --
you set out on an activity where you're making a wholesale
modification of the regulations? How useful is that
definition to you in doing that activity?
DR. FLACK: Well, I think -- yes, I think you're
touching upon a point of public confidence. I mean, when we
have established adequate protection, it's something that we
believe that we have done with our regulations and that
plants do adequately protect the public. I mean, that's the
position that you're coming from up front, and the
regulations are trying to establish what that is. I mean,
they do establish what that is.
But there's also goals that you want to aspire to,
and I think this is where you stand back, and you look at
the broad set of the regulations and how they're being
implemented and what they're achieving and then what are we
trying to achieve, well, in steps to safety goal? Well, the
safety goal is a way of articulating what we're trying to
achieve. It's something that you try to aspire to. And I
think in that context, one can, you know, sort of understand
what role each of these play.
Now, ultimately, it would be the -- ultimately,
they should come together. When we have all the answers, I
think it will come together. But as this continues to
evolve, and we get closer and closer as we evolve, I think
we're coming closer and closer together. But I don't know
if we have all the answers yet. I mean, we always have to
question that, you know. And so, I think that goals
shouldn't be met; they should be something that we're saying
here's what I'm trying to aspire to. I mean, in some cases,
you might meet them, and that's fine, but it's not something
that should be in the sense of a requirement, you know, that
you have to meet these goals.
So again, why? Why do we need risk? We have the
PRA policy statement that goes through a number of reasons
why we think it's important, the Commission thinks it's
important to use risk concepts, and those would be
explained, of course, as part of that up front discussion
and class. And then, we talk about the strategic plan and
what's the relationship between the strategic plan and the
risk-informed regulation implementation plan, which you'll
soon hear about; this is the one that the staff has been
working on and presented to the Commission I guess it was
about a month ago.
Now, and I visualize the strategic plan again as
those strategic goals on top, and then, we have performance
goals which we expect to meet, and then, between the two,
you need some implementation plan. How do you go from your
strategic goals to how you're measuring or what's causing
you to measure what you're measuring? And that, to me, I
envision that as the piece, the dovetailing of the risk-
informed regulation implementation plan.
So with that fitting together like that, that
would explain why we're -- and risk-informing the plan
itself would explain how the policy itself is being
implemented, the Commission's PRA policy statement.
So I see those two as dovetailing, anyway, in that
sense of the word, but we're still working on developing the
risk-informed regulation implementation plan and laying that
out and how that will -- then, we will get down to the
regulatory activities and how those are being risk-informed.
So I see that as an introduction to the students
as to why we're using risk. And then, we move on to the
principles of risk-informed integrated decision making,
which is Reg Guide 1.174, where there's a lot of information
there that is generic, which is the way we do business using
risk, and that carries over certainly to the other fields.
And then, as we move through this cost, we begin at a higher
level moving down now to its actual applications to
materials and waste disposal, and right now, the document
that really outlines that is SECY 99-100, which you're
familiar with and how we're implementing that process.
And then, of course, the connection with respect
to nuclear materials and waste of how we use risk and
rulemaking, licensing and inspection and assessment as being
those three key regulatory areas by which we operate and
drawing that connection between -- to risk and the
regulations. So again --
DR. GARRICK: John, I hope that the emphasis on
this, on the training is not so much on the why being
answered in the context of because we have rules and
regulations and what have you but rather what's behind the
reason we have the rules and regulations. I don't think the
American public is all that impressed with the why being
answered, being given in the context because it's required
by the regulations. I'm just suggesting -- and I hope the
emphasis is on the merits of a risk-informed approach.
DR. FLACK: Yes.
DR. GARRICK: The merits of a risk perspective,
because this is not very impressive to me just to see this
list, because, you know, I don't -- I'm a member of the
public; I don't trust the Government. I want something more
basic than safety goals and PRA policy statement and
strategic plans and regulations and what have you. I want
somebody that really understands what we're going to benefit
from in taking a risk view here and that understands what
risk is. So I hope the emphasis is on that.
DR. FLACK: Yes; I would say -- well, I guess
there's a couple of things. I understand the emphasis that
you're making as certainly important to make. The objective
-- this gets back to the objectives of the course, and what
I'm laying out is more of an outline with the objective in
mind that we want to bring the staff up to speed in risk,
and we want the staff to understand why risk is important to
use it, why it's important to know, and how does it fit in?
So the emphasis was more on the staff itself rather than the
public domain. So there is a part that I'll get to in the
end about risk communication, and that is how do you
communicate to the public.
DR. GARRICK: Yes.
DR. FLACK: But that comes at the very end of the
list, and this is only meant to be the establishment of an
outline. I mean, there is a lot of meat that needs to be
put on the bones.
DR. GARRICK: Yes.
DR. FLACK: But it's just the way we're thinking
through the process of training the staff in the Office of
NMSS --
DR. GARRICK: Yes.
DR. FLACK: -- to appreciate the views on it.
DR. GARRICK: But my point is that the real reason
we're doing risk assessment is, A, we want to know what the
risk is in a realistic fashion; that it's something more
valuable to us than a bounding analysis. That's the real
merit of a risk assessment. And number two, we want to know
what's contributing to the risk.
DR. FLACK: Yes, absolutely.
DR. GARRICK: And so that we can do something
about it.
DR. FLACK: Yes.
DR. GARRICK: So that we can manage it. And when
I see a list like that, I don't see --
DR. FLACK: Well, I get into the other pieces.
DR. GARRICK: Yes.
DR. FLACK: This is still at a very high level.
DR. GARRICK: Right; I understand.
DR. FLACK: And now, we get into the next piece.
Let me move ahead to the methodologies and then what comes
out of those methodologies and then how do we use those
findings.
DR. GARRICK: Yes.
DR. FLACK: So this is still establishing the up
front why risk is -- why we're using risk, and certainly,
the outputs and the outcomes of using risk is something
that's important.
DR. GARRICK: Yes.
DR. FLACK: You know, that adds to what our
knowledge base is, and really, that's the main thrust.
DR. APOSTOLAKIS: But why we're using risk; I
think part of what John said answers that question in the
motivation behind it so it belongs here really, doesn't it?
That you really want to avoid -- to get away from
conservative bounding analysis, a more realistic view of
what's going on. Maybe that should be the very first
bullet, even above the safety goals.
DR. FLACK: Well, yes, I mean, you discussed that
in the context of goals and adequate protection and --
DR. APOSTOLAKIS: You can even bring it up there,
yes.
DR. FLACK: I mean, that's really -- you know --
DR. APOSTOLAKIS: Oh, so you were planning to do
that --
DR. FLACK: Yes.
DR. APOSTOLAKIS: Yes.
DR. FLACK: That would be part of what we mean by
adequate protection versus --
DR. APOSTOLAKIS: I see.
DR. FLACK: -- a safety goal.
DR. GARRICK: Well, yes, if you do a job of
marrying this list and its language to the background, like
you said, you said when you were talking about safety goals
versus adequate protection that there's language in the
rules and regulations of a background of the type that we're
talking about here. But just wanted to make the point that
that's quite important, that background information.
DR. FLACK: Yes; and I think when you flesh out
why, you know, you have a PRA policy statement to begin with
and the reasons that led you there --
DR. GARRICK: Right.
DR. FLACK: -- were some of the reasons that
you're describing now. So, I mean, there needs to be a lot
more, again, meat on the bones here, but just as a
structure, you're quite right. I mean, these things have to
be brought up. I think that one of the shortcomings that I
see is that we tend to jump into teaching students the tools
and the methods, and you say okay, now, go forth and use
them, but there's not enough up front discussion of why do
you use risk? What is risk, you know, doing for you, and I
think these are the kinds of, you know, things that need to
be discussed; right.
Okay; which gets me to the second part, and that's
the what, and that is, you know, as part of that -- part of
the course; it's to go through also the methodologies and
what are the -- what they are, the concepts, the methods.
And through that discussion, of course, of what risk is and
then the general methodology that's used in finding out what
that risk is and then the key modeling areas, and these
configuration or with reactors, of course, it's as built, as
operated plant or operating condition and what we mean by
success and how that's modeled. Of course, human
reliability is an important part of that methodology and
common cost failure, accident progression and consequence
analysis and external events. So these are all the key
modeling areas that one would discuss in a course like this
to get ideas to students on how or what is, you know, this
is the what, what modeling areas there are out there that
need to be done.
And then, following that, of course, then, we get
over to the data, statistical analysis and treatment of
data, and there will be some of that as part of the course;
basic treatment of uncertainties, and this, of course, is
trying some limitations of the methods. So this would be in
that context of getting out the methods, explaining to the
students what methods are out there and how they're going to
be applied will then follow.
DR. KRESS: Go ahead, George.
DR. APOSTOLAKIS: The uncertainty treatment in the
statistical analysis, the biggest uncertainties, at least in
reactors, are usually associated with models themselves, not
the data failure rate kind of thing. Is that part of what
you're going to discuss here, even though there are no
methods really for handling those, but the model
uncertainties really drive the whole thing. And I think a
lot of staff's regulations come from that.
DR. FLACK: Well that clearly, I mean, this is --
the assumptions that go into even the model need to be
articulated well.
DR. APOSTOLAKIS: Right.
DR. FLACK: How you deal with that, it's helps to
understand that in the context of the limitations of the
process, that one is dealing with what we believe to cover
the -- what the model is expected to cover based on the
assumptions that go into the model, and certainly, that
comes out; that would need to be discussed in the context of
uncertainties.
So once that groundwork is established, then, it
becomes more the data uncertainties that we're talking
about, but both uncertainties play an important role. You
know, I tend to agree with you. I think that's one of the
reasons why, you know, we're more in a risk-informed
arena --
DR. APOSTOLAKIS: Yes.
DR. FLACK: Because of that, you know.
DR. APOSTOLAKIS: That's right.
DR. FLACK: And it's really to open your eyes to
look for these things and not to say you got them all, I
think, is -- you know -- is the answer to that but -- okay;
so, moving off from the methods, we get to the applications.
And here's where I relied on my team members to actually
provide us with a lot of input to this, so we've met with
the training instructors, and we have identified some
specific applications, and now, we're into how do you use
these methods?
And those are, you know, the four that we have
established is fuel fabrication, one for fuel fabrication,
one for transportation, one for nuclear materials and by-
products, which you'll hear something about today, and
radiological waste disposal. So each of these, essentially,
has their own methodology. So we've developed sample
applications of that and turned those over to the
contractors, and now, the team members, each team member has
a domain that they'll be interacting with the instructors on
so at least the students who take this course see the
practical applications of these methods as we're using them
today in the NRC.
Each of the examples that have been developed for
those particular areas, of course, need to address certain
elements, and of course, one is the differences in
methodology; each has its own methodology, as mentioned; the
key assumptions, which gets back to the modeling question;
data analysis; the results and findings; what comes out of
that analysis; and then, how do you use those findings or
insights in decision making? So trying to get out already
what's going on more globally within the office is really
the intent of that, of those applications.
Okay; that's sort of the how.
DR. MARKLEY: John, just one question. In your
developing an appreciation for the staff for the use of risk
information and the analysis methods, are you going to be
developing something comparable to the senior reactor
analyst, where you have people in the various areas that
will be more or less responsible for doing some of the
analysis associated with it along those lines to support
those activities in the field and stuff?
DR. FLACK: Well, we haven't gotten -- we really
haven't gone that far yet. We're thinking about -- if we're
talking about significant determination processes and
specific findings and how they're assessed, I believe that's
an area that we still need to pursue. So we don't have, per
se, like SRA types within NMSS. We have a group, though,
and certainly, as things get more interesting and get
brought in, what is the risk perspective of this, then, the
group would take it more or less on, and then, the expertise
within the group would deal with the issue. But there is
not an assignment or a specific individual assigned like a
similar --
DR. MARKLEY: But the group is a group of risk
analysts, per se, or are they people with experience in
those technical areas?
DR. FLACK: Both.
DR. MARKLEY: Both?
DR. FLACK: Yes.
DR. GARRICK: John, there is one thing that always
bothers me about training syllabi that I see in the risk
field, and they don't somehow match up very well with the
real world in terms of activities. I look at your examples
on your previous slides of methodology and application, key
assumptions, data analysis, results and findings, insights
and use and decision making. The most important activity in
a risk assessment is what I would call the building the
logic models, answering the question what can go wrong?
It's probably 70 percent of the risk assessment,
and yet, there is a kind of this idea conveyed out here that
a risk assessment is primarily analysis of data. That may
be 5 percent of a risk assessment. The thing that's really
the tough, hard-nosed stuff in doing a comprehensive risk
assessment is not clearly identified in that kind of a list.
Now, it could be buried in the notion of methodology and
application, but where the man-hours are really spent, and I
speak to you from having directed over 40 of nuclear power
plant PRAs, is in developing the logic models, the event
sequence diagrams and the fault trees that answers the
question what can go wrong?
And that's where the real value of the risk
assessment comes from; you know, people say that you can't
do a risk assessment if you can't do data, if you don't have
data, and of course, that's complete nonsense.
DR. FLACK: Right.
DR. GARRICK: Because that's not where the energy
is consumed. The energy is consumed in understanding how
the plant works.
DR. FLACK: Yes, right.
DR. GARRICK: And you understand how the plant
works when you start answering the question what can go
wrong, and the way you answer that question is through a
structured set of scenarios.
DR. FLACK: Yes.
DR. GARRICK: And somehow, that just doesn't come
through.
DR. FLACK: Yes; no, I --
DR. GARRICK: And that's where the whole
brilliance of a good risk assessment is.
DR. FLACK: Right, exactly, right, right.
DR. GARRICK: If you don't have people who
understand how the plant works but might be the world's
expert on data analysis; might be the world's expert on
methodology and so forth, you're going to get a lousy PRA.
DR. FLACK: I couldn't agree with you more.
There's always limitations in a course like this.
DR. GARRICK: Yes; I know, but I just couldn't
resist it because --
DR. FLACK: Yes; I --
DR. GARRICK: Because there is --
DR. APOSTOLAKIS: I count this as something else.
DR. GARRICK: Yes.
DR. APOSTOLAKIS: If you have people who know the
plants very well, and they don't understand data analysis
and methodology --
DR. GARRICK: Well, I know, I know. I know,
George, but that's there; that's there.
[Laughter.]
DR. APOSTOLAKIS: You know, just for the record.
[Laughter.]
DR. GARRICK: That's represented. But the real
hard work of a PRA does not seem to be represented.
DR. FLACK: Yes.
DR. GARRICK: That's my point.
DR. FLACK: It's hard to get that appreciation
from someone just quickly going through one of these
examples, and certainly, these examples that are presented
take an enormous amount of time. I mean, there's a lot of
resources that went into these, and in a couple of pages,
you present that to them.
DR. GARRICK: I understand; I understand.
DR. FLACK: So it's just the fact that the people,
to really appreciate it, need to do it.
DR. GARRICK: Yes.
DR. FLACK: And when they do it, they'll
understand it, but it's to get them there. The whole idea
is to get them there.
DR. GARRICK: John, my main point is that a PRA is
principally an engineering analysis problem. It's
principally an engineering and operations analysis. And
that is something that has to be emphasized in the training.
DR. FLACK: Yes; I agree.
DR. APOSTOLAKIS: Maybe under examples to include,
there ought to be a bullet that actually addresses that.
You know, I don't know how to put that --
DR. GARRICK: Well, the closest thing I know --
right; the closest thing I know, George, is something like
logic modeling.
DR. APOSTOLAKIS: Yes.
DR. GARRICK: It's something that really gets --
gets it.
DR. APOSTOLAKIS: Structuring the scenarios?
DR. GARRICK: Yes; structuring the scenarios.
DR. APOSTOLAKIS: I think that would be a good
addition.
DR. GARRICK: Structuring the scenarios.
DR. FLACK: We're just writing it as methodology.
DR. GARRICK: Yes.
DR. FLACK: Structuring and scenarios.
DR. GARRICK: Well, structuring the scenarios.
DR. FLACK: Structuring of scenarios.
DR. APOSTOLAKIS: Do you want to call them failure
scenarios or --
DR. GARRICK: Well I --
DR. APOSTOLAKIS: Because it's not really -- we
call them accident reactors.
DR. FLACK: Yes; I understand.
DR. APOSTOLAKIS: That's the word that applies to
NMSS, the scenarios.
DR. GARRICK: Scenario is okay.
DR. APOSTOLAKIS: Scenarios.
DR. GARRICK: Because that --
DR. FLACK: They will certainly cover that as part
of the -- you know, like, for example, the event reanalysis,
but again, the appreciation of actually doing it in the real
world is -- you just can't get that across in the classroom.
You have to summarize it, you know.
DR. GARRICK: Yes.
DR. FLACK: But certainly, we'll reemphasize that
as another bullet.
DR. APOSTOLAKIS: Good point.
DR. FLACK: Okay; so, then, that leaves us with
the last two areas of the training program, which would be
the application of the risk insights to regulatory decision
making, but it's not just generating things and not being
used. And here, also using the tool once it has been
developed to gain insights by performing sensitivity studies
and bounding analysis, and that gives you more information
about -- about whatever you're modeling the area; the impact
of uncertainties through those sensitivity studies, and some
of this last one, performance measures, is something that
you would gain by doing an analysis and understanding what
are the important measures, important performance measures
to capture and then use, for example, to demonstrate that,
in fact, you are achieving what the model is predicting,
something that you could actually measure in the course of
time.
DR. KRESS: Somewhere in these six areas, you have
a concept of how defense-in-depth fits in with a risk-
informed or risk application processes?
DR. FLACK: Well, other than how it would be
discussed in the context of 1.174 up front, you know, what
we -- you know, how it becomes one of the elements,
principles of good regulation, I wasn't going to go venture
into what we mean by that in the context, you know, of the
applications at risk.
DR. APOSTOLAKIS: You know, John, when you talk
about uncertainties and their impact on decision making,
maybe that's a good place to --
DR. KRESS: That would seem to me like the right
place to put it, yes.
DR. APOSTOLAKIS: Especially model uncertainties,
because if you think about the, you know, motivation for
defense-in-depth, compensatory measures is really the
uncertainty you have. Now, again, you don't need to give
them a whole treatise on it, but you have an item here
insights and use in decision making, for example. That's
where a discussion of defense-in-depth versus the rational
approach to designing compensatory measures would belong. I
mean, just as a thought. I mean, you don't have to decide
now, but it's certainly an important issue.
DR. FLACK: Oh, it is, but the question is can it
be confusing within that context?
DR. APOSTOLAKIS: It is already confusing.
[Laughter.]
DR. FLACK: Well, this is true, but it should be
something that's borne out. It's -- there's almost you're
working like between two worlds, one of being --
DR. APOSTOLAKIS: Exactly.
DR. FLACK: -- deterministic and one of being
probabilistic, and then, you're trying to bring the two
together to have it make sense within the principles of
1.174, and the question is how does one articulate that in
the context of a training course? A lot depends on the
instructor, and it's not going to be me, which is
unfortunate. Otherwise, maybe I could discuss this with --
you know, the problems and the issues that come out of how
we deal with these as things we're trying to blend the two.
But I guess in concept, what we're trying to
achieve -- establishing defense-in-depth mechanisms to
account for uncertainties, which is why you wouldn't want to
remove the containment, for example -- certainly is an
appropriate thing to talk about in the context of the
course.
DR. APOSTOLAKIS: The -- well, again, I mean,
1.174 is a pioneering document, but the way defense-in-depth
is presented there is a third principle; the connection
between defense-in-depth and risk assessment is not very
clear.
DR. FLACK: Right.
DR. APOSTOLAKIS: And it's okay; I mean, that was
the first time we wrote something like that. But I think a
discussion of defense-in-depth in the context of the
uncertainties that will come out of all of these analyses
would be a more reasonable thing to do and explain at least
the connection --
DR. FLACK: Yes.
DR. APOSTOLAKIS: -- that --
DR. FLACK: And there is a structure to it, you
know, I think. You know, as you become -- of course, as you
go down further and further in the likelihood of events, you
would have less and less defense-in-depth because of the low
probability of the event, where events that you would expect
that would occur, you would expect a lot of defense-in-
depth, and that would still bring you down to this low
probability. So, I mean, they kind of trade off against one
another. As a reactor tripped, there's a lot of defense-in-
depth to bring the plant to a safe shutdown. Of course, in
the extreme, there is no defense-in-depth for a meteorite,
for example; I mean, it just happens; that's it.
So, I mean, in between, you have the whole
spectrum of --
DR. APOSTOLAKIS: Yes; we are not saying that
these issues are crystal-clear to everyone, but at least the
discussion of defense-in-depth --
DR. FLACK: Sure.
DR. APOSTOLAKIS: -- of the context of the
uncertainties and their impacts on decision making, and that
will naturally bring you back to the model uncertainty
issue, because that's a major driver. I don't think there
is any defense-in-depth measure that was placed there
because the distribution of lambda was too broad, the
failure rate. I mean, it's really the model itself that you
worry about.
DR. FLACK: Yes; good point; okay.
DR. APOSTOLAKIS: And that's where, in fact, I
would agree with John. I mean, that's where the
availability of methodologists has actually done a
disservice to the community; because there is so much
statistical literature on how to handle failure rates, we
can pay a lot of attention to that, when, in fact, from the
PRA perspective, they are not the major drivers.
DR. FLACK: Yes.
DR. APOSTOLAKIS: Uncertainties in failure rates
are not the major drivers, right?
DR. FLACK: Yes; well, you tend to go to the area
where it's the easiest to --
DR. APOSTOLAKIS: At the moment you assume it's
exponential, you have already made a big assumption.
DR. FLACK: That's -- okay; good, and the last one
is, of course, risk communication. We were discussing how
it is important to communicate the results, both internally
and externally, and there is work obviously still going on
in that arena right now, and we don't have all of the
answers to it but to at least emphasize the need to do this
as part of this course.
Okay; so, those were the six areas of the pilot
program. Then, if there are no further questions, I'll move
on to the workshop.
DR. APOSTOLAKIS: Let me -- risk communication; I
know it's a fashionable term. Shouldn't it really be
replaced by building trust or something? That's really what
you want. You want the public to trust you, not just to
communicate -- the risk communication is part of it. And
I'll give you an example. In talking to people or laymen,
they have no idea how you guys develop regulations and the
extensive reviews and the public comment period and so on.
And it seems to me that their confidence in the agency goes
up after they realize how much scrutiny every document you
produce goes through, and that's not part of risk
communication. That's building trust.
So I was wondering whether we can start talking
about trust, of which risk communication is a very important
part but not just risk communication. I mean, you have
processes in place that really the general public are not
aware -- they are not aware of. And yet, they enhance --
they should enhance the confidence they have in you. They
don't know that this committee exists and that, you know,
everything is aired in public, and we are free to say
whatever we like, and the public is free to come and
participate.
DR. FLACK: Yes, right.
DR. APOSTOLAKIS: I mean, that's important.
DR. FLACK: Yes; yes, well, this really gets into
external communication in general; I mean, how we
communicate to the public.
DR. APOSTOLAKIS: Yes; so, in fact, the thing you
have in parentheses there, public confidence --
DR. FLACK: Yes.
DR. APOSTOLAKIS: -- it seems to me that should be
the heading.
DR. FLACK: Instead of risk communication.
DR. APOSTOLAKIS: And risk communication is under
it.
DR. FLACK: Well, okay, but we also have internal
communication.
DR. APOSTOLAKIS: Yes; that's true.
DR. FLACK: Which is important too.
DR. APOSTOLAKIS: Internally, you don't have to --
they know what the processes are; I mean, all you have to do
is communicate risk.
DR. HORNBARGER: You hope they already know.
[Laughter.]
DR. APOSTOLAKIS: All the evidence to the
contrary, you know; 70 percent of you guys don't think risk-
informed regulation will go anywhere. That's still true.
DR. KRESS: Who took that poll?
DR. APOSTOLAKIS: Was it the IG or someone?
DR. KRESS: IG?
DR. APOSTOLAKIS: Do you remember?
DR. FLACK: Yes; well, in light of that I was
thinking of how the information gets -- that's being used
again; the risk group is a support group, and it's generally
supporting a technical area. Well, how do you package the
results from your risk studies so that the technical area
can use that, capitalize on it? Some of the things that
John had been mentioning has to somehow get across to the
people that are going to use this to make the decisions.
That generally will not be the risk analyst that makes the
decision. It will be someone in the technical area.
So that bullet was intended to somehow get -- to
get the output from this analysis in a form that is usable
and will be used by somebody making those technical
decisions.
DR. GARRICK: Also, it's a risk course, so I can
understand why you would put communication or risk
communication as a headline, even though I agree with what
George is saying, that what we're really talking about here
is how to build public confidence.
DR. FLACK: Yes, clearly.
DR. GARRICK: How to build trust.
DR. FLACK: That second bullet is getting to the
public that we're using risk. We're doing regulation in a
smart way, and one of the things we're using is risk to do
it and getting that point across to the public. I mean --
well, as we'll get into the workshop, you'll hear some of
these public groups think risk is just the opposite; that
it's a means for relaxing the regulation. And so, there's
always this other element that's there that --
DR. APOSTOLAKIS: And if you talk to the industry,
it's the other way.
DR. FLACK: That's right; so it's -- there's
always sort of a problem with that, too.
DR. GARRICK: Let's talk about that workshop.
DR. FLACK: Okay; moving on to the workshop, the
workshop was held last week, April 25 and 26. There were
approximately 50 people who showed up at the workshop.
There were about 26 participants around the large table.
The objectives of the workshop were to both inform and
obtain stakeholders' input on two things. One was the
criteria, which Marty had mentioned this morning, earlier
this morning on how to decide whether a certain regulatory
activity should be risk-informed, and the other was on the
nuclear safety goals.
As part of the Federal Register notice that went
out, we provided the five-step implementation process out of
SECY 99-100. We also listed the criteria, proposed
criteria, and then, we listed a number of questions that we
thought as food for thought that they would have behind
their minds as they participated in the workshop. And I
kind of structured the feedback along those questions we had
asked.
This view graph just provides an overview of the
organizations that were represented, which gives a pretty
broad spectrum of participants. Again, there was
approximately 20 to 25 that sat around the table that
participated in the discussion. The next view graph shows
the framework that was outlined in SECY 99-100; the five-
step process. The first was to identify candidate
regulatory applications that are amenable to expanded use of
risk assessment information, and we primarily focused on
that one. The others kind of flow from that: decide how to
modify regulation -- the regulatory activity, and we'll
discuss a little about case studies that are being proposed
on how do we do that, use that to decide how regulation
might be modified.
And then, once we ran a pilot, we would then think
about changing the regulation and then implementing that new
regulation and then what it would take as far as tools to
make that happen. But I don't see these five steps as
naturally occurring one after the other. There's a lot of
feedback from, you know, what you do depends also on what
tools you have and that sort of thing, so kind of -- there's
a lot of feedback between the various steps, but we
primarily, as part of the workshop, focused on number one.
The next view graph paraphrases the screening
criteria, and those -- that was three, three items on that.
So if we were proposing a risk-informed activity, a new
activity that would change the way we do business; the first
one would say the new regulations should be at least -- it
would have to at least address one of these: maintaining or
improving safety; improving the effectiveness or the
efficiency of the NRC process; and/or reduce unnecessary
burden.
DR. APOSTOLAKIS: Now, the moment you say reduce
unnecessary burden, shouldn't you add a fourth item, add
regulations where appropriate?
DR. FLACK: Add regulations --
DR. APOSTOLAKIS: Well, I mean, the risk analysis
may indicate that there are areas where you need more.
DR. FLACK: Oh, well, I --
DR. APOSTOLAKIS: Because this, you know,
regarding communication with the public, I mean, we're
overdoing it with the reduction of, you know, unnecessary
burden, and, I mean, that's not the purpose why we're doing
all this.
DR. FLACK: Right. I see the first bullet and the
third bullet working together, you might say. When you
bring them together like that, you kind of say we're doing
smart regulations. If it results in a decrease; that's
fine. If it results in an increase, that's fine. We're
just doing it the smartest way we know how to do it.
DR. APOSTOLAKIS: But what you just said is great,
but it doesn't come across.
DR. FLACK: Yes, it --
DR. APOSTOLAKIS: So, if you decide to put a
bullet reduce unnecessary burden, it seems to me you have to
have something also that says that you may add something if
you find there is a hole someplace or just delete it.
DR. FLACK: But the question is if we add that as
a bullet, if we say, well, it meets that bullet, that bullet
is linked to one of the other bullets. It's not by itself a
bullet. Like you would say I would add a regulation, but it
would need to either reduce burden or improve safety or
something like that.
DR. APOSTOLAKIS: Something like that, yes.
DR. FLACK: Right; I mean it's --
DR. APOSTOLAKIS: I would make it one bullet;
you're right.
DR. FLACK: So we would have to sort of implicitly
be that and one of the others.
DR. APOSTOLAKIS: The reason why I'm saying this
is I don't really think it affects the substance of things,
but the last three or four years, we've been talking a lot
about reducing unnecessary burden, and the agency has been
criticized that the reason why we're doing all this is to
reduce burden, and that's not true. That's not true.
DR. GARRICK: It's a by-product of the process.
DR. APOSTOLAKIS: It's a by-product, and for 20
years, we've been using PRAs to add regulations.
DR. FLACK: Well, that's --
DR. APOSTOLAKIS: And, of course, people
conveniently forget that.
DR. FLACK: That's right, and I think it's only
saying, well, at this point, I'm going to go back and look.
We haven't taken anything; we've kept adding and adding, and
maybe there's things that got superseded and something that
could be -- and so, it's really a -- well, we went through
this phase, then, to -- let's look at it from a different
perspective. What is out there that we can reduce; since
we've been adding and adding and adding over the years, is
there anything now that's not just worthwhile going and
implementing?
And now, I think we're coming back to the point as
though we're doing it as a group thing. When we look at
something, we look to see if there's -- safety can be
improved or we can reduce, and I think they come together
now at this point. We're not looking at one or the other;
we're looking at both simultaneously.
DR. HORNBARGER: In fact, that strikes me that
your first bullet there is essential. It's not one or more
of the following; the first always has to be satisfied.
DR. APOSTOLAKIS: Right, and the second, too.
DR. MARKLEY: George, I think as long as you're
relying on licensees to identify the initiatives, you're
going to end up with burden reductions and not increased
regulations or enhancements.
DR. APOSTOLAKIS: But, Mike, I'm not questioning
the actual practice. I know that we're trying to do the
right thing, and we are most of the time. I'm just
addressing what's written there.
DR. MARKLEY: Right.
DR. APOSTOLAKIS: And because of the recent
criticism, I mean, I have no -- there's no question in my
mind that we are not doing this just to reduce burden, but
we have been criticized that we are overdoing it with the
reduction, and we keep talking about it all the time, so
either delete it or add something to the effect that if
necessarily, you know, we will add something. We will add
unnecessary burden.
[Laughter.]
DR. HORNBARGER: No, no, you make it completely
parallel, and the fourth one is add necessary burden.
DR. APOSTOLAKIS: Right, right, right; that's
exactly it.
DR. FLACK: Add necessary burden.
DR. APOSTOLAKIS: Yes.
DR. FLACK: And I think the point is well taken,
as you'll see in some of these comments back from the
workshop -- well, one of the public citizen groups felt that
the last two of these criteria should not be part of it.
DR. APOSTOLAKIS: That's right.
DR. FLACK: They only believe that the first one
should be part of it. And that was their position.
Obviously, that wasn't shared by everyone in the room, but
that's where they were coming from. But we'll take that --
you know, we'll think about that, what you said, and see if
we can change -- see what we can do to clarify the meaning
of that first --
DR. APOSTOLAKIS: Okay.
DR. FLACK: -- first criterion.
The other two, of course, are that there needs to
be data and analytical methods available or able to be
developed if you want to make that change work, and then, of
course, it's the implementation, whether it can be realized
at a reasonable cost. Again, this looks almost like the
why, what, how, whether you start with the why are you doing
it and then what, what it is that you plan to do and then
how are you going to do it; it sort of flows in the same
kind of logic.
So that was the criteria that was proposed, and
there is a comment period that's still open, and we're still
waiting to hear from others on that as well. I don't know
if we'll get --
DR. APOSTOLAKIS: Well, again, in the context of
the criteria, though, I don't know what it means maintaining
or improving safety. The criteria are -- will tell you
whether you should risk-inform a particular activity, right?
That's what Virgilio told us earlier. The screening
criteria; what's the purpose of the screening criteria? To
decide --
DR. FLACK: To see if -- yes, to see if there is
an area of the regulation that could be risk-informed and
then why would you --
DR. APOSTOLAKIS: How can maintaining safety be
part of the criteria? I don't see that, and, you know, I
just don't see that.
DR. FLACK: It could be part -- well, okay.
DR. APOSTOLAKIS: I mean, that's a consideration
when you decide to do something, and you're asking yourself
now, what should I do? Well, then, you say of course,
whatever I do, I have to maintain safety. But it is -- or
improve it, but it's not part of the screening criteria, I
don't think.
DR. FLACK: Well, it almost says that if, you
know, it goes hand-in-glove with the last bullet, which says
that if you have a proposal that you wish to reduce burden
that you would at least maintain safety while doing that or
improving safety, but that would be a win-win situation.
DR. APOSTOLAKIS: Right; but this is a
consideration after you decide that there is unnecessary
burden.
DR. FLACK: That's right; you would first decide
that -- yes.
DR. APOSTOLAKIS: It's after that.
DR. FLACK: Yes; you would first observe that.
DR. APOSTOLAKIS: Your first decision, the
maintenance of safety really is irrelevant.
DR. FLACK: Yes; it's almost like an overarching
kind of principle that --
DR. APOSTOLAKIS: Yes; we always want to maintain
safety.
DR. FLACK: Yes, right.
DR. APOSTOLAKIS: There's no question about it.
DR. KRESS: A criterion might be does this
particular regulation have a high risk or a high impact on
safety. That could be a criterion.
DR. APOSTOLAKIS: This regulation; no, you're
looking at activities, right?
DR. FLACK: Activity.
DR. APOSTOLAKIS: And you're asking yourself
should I risk-inform this part of -- the regulation of this
activity.
DR. KRESS: Yes; then, you're going to -- you're
going to risk-inform all the activities.
DR. APOSTOLAKIS: Yes.
DR. KRESS: The question is which parts of the
regulations? And you look at the individual regulations and
say does this have a high impact on safety, a high impact on
the safety of this particular area? That could be a
criterion.
DR. APOSTOLAKIS: Why would that be a criterion
for risk-informing it?
DR. KRESS: Well, if you have to -- if it was low-
impact, there's not much reason to risk-inform it, maybe.
Yes?
DR. ROSENBERG: Hi; I'm Stacy Rosenberg. I'm in
the risk task force. The first criterion is to resolve a
question with respect to maintaining or improving safety, so
that's what we're looking at is if there is a question --
DR. APOSTOLAKIS: Oh.
DR. ROSENBERG: -- with respect to maintaining or
improving safety, we would want to use a risk-informed
approach to try to answer the question.
DR. APOSTOLAKIS: Then it should be restated here
to make that clear.
DR. ROSENBERG: That's just paraphrased from
the --
DR. APOSTOLAKIS: In other words, there is an
issue that has come up --
DR. ROSENBERG: Exactly.
DR. APOSTOLAKIS: -- that creates a question --
DR. ROSENBERG: Right.
DR. APOSTOLAKIS: -- whether safety is maintained,
and then, that can be -- and the thought is that by risk-
informing the process, you will be able to place that issue
in perspective and maybe resolve it.
DR. ROSENBERG: Right, right.
DR. APOSTOLAKIS: Oh, okay, yes.
DR. GARRICK: But isn't this just parroting the
background information to the PRA policy statement? These
words have appeared many, many, many times and in this
order, too: maintain safety; make the NRC more efficient;
and reduce licensing burden if it can be justified.
DR. APOSTOLAKIS: But, John --
DR. GARRICK: Yes.
DR. APOSTOLAKIS: -- they are used there after you
decide to risk-inform the regulations. The Commission is
telling you do these things; risk-inform the regulations,
and in the process, make sure you are maintaining safety and
so on. But here, they're deciding whether to risk-inform.
And that's why I raised the question, but after the
clarification, I think if you change the words, then, it's
okay.
DR. FLACK: Yes; that should have been the
question up front.
DR. APOSTOLAKIS: Yes, that is the question.
DR. FLACK: That's on the table that you were
going to address.
DR. APOSTOLAKIS: Makes sense.
DR. FLACK: And then, you would just bring the
fourth as a question. Of course, it's also being exercised
in the other arena as well as part of the policy statement.
DR. KRESS: Yes.
DR. APOSTOLAKIS: The other thing is the data. I
don't know if you like that, John. I mean, if we don't have
data, we don't do risk assessment.
DR. KRESS: Similar to your question, George, the
second one there: improve the effectiveness of -- you know,
that's a weird criterion in a sense that almost anytime you
risk-inform the regulations, it's probably going to improve
efficiency. The criterion ought to be maybe does this area
have a high impact on the --
DR. APOSTOLAKIS: Yes.
DR. KRESS: -- effectiveness or efficiency or
something like that. And it seems like improve is not the
right criterion.
DR. APOSTOLAKIS: Well, I think the words were
borrowed from --
DR. KRESS: Yes, I think the --
DR. APOSTOLAKIS: -- documents that John Garrick
mentioned without really adapting them to the fact that you
are talking about screening criteria here, whether to risk-
inform or not. And the context they have been used in the
past is after you decide to risk-inform, make sure these
things are right.
But number two, I mean, why would that be a
consideration in the screening criteria if the principle is
-- and that's why we have fault trees; that's why we have
all of these things. If you don't have data, you go deeper
and deeper until you get some evidence that will be used,
and the availability of data was an issue in 1970 when
people were telling other people that the reactor safety
study would never be completed, because you don't have the
data. And then, it was completed. So I don't know that
number two means anything. That's why we do risk
assessments, right?
DR. GARRICK: Yes; I don't have too much problem
with it when it's in the context of analytical methods, when
it's data and analytical methods. You know, the analytical
methods are what allow us to turn up the microscope on the
system such that we can see it down to a level of where some
evidence, some data exists. So it doesn't have the same
impact as it would be if -- as a statement that you often
hear, namely, you can't do a risk assessment because you
don't have the data.
DR. APOSTOLAKIS: That's right; that's right. We
need data.
DR. FLACK: In the context of whether or not data
becomes important as part of your decision, if you need to
collect additional data.
DR. APOSTOLAKIS: They're always important.
DR. FLACK: Yes.
DR. APOSTOLAKIS: Data are always important.
DR. FLACK: Okay.
DR. APOSTOLAKIS: The existence of data should not
be a driver.
DR. FLACK: Yes, that's true.
DR. GARRICK: Information, yes, perhaps.
DR. APOSTOLAKIS: But data at what level?
DR. FLACK: Yes.
DR. APOSTOLAKIS: See, it can be misinterpreted.
It may be at a much lower level.
DR. GARRICK: Evidence is another word that would
work.
DR. FLACK: Evidence?
DR. GARRICK: Yes; evidence and analytical methods
exist.
DR. APOSTOLAKIS: I would say just analytical
methods to make it clear.
DR. GARRICK: Yes.
DR. APOSTOLAKIS: Because it's too subtle
otherwise.
DR. GARRICK: Yes.
DR. FLACK: Okay; any other questions or comments
on the screening criteria?
DR. APOSTOLAKIS: If I were picky, I would ask you
what is reasonable cost, but I am not.
[Laughter.]
DR. FLACK: Moving right on --
[Laughter.]
DR. FLACK: Okay; so, the next -- these are the
comments, actually, that we received on the screening
criteria. First one is not a surprise; any new requirements
should be established using a risk-informed approach. I
think there was general consensus on that around the table.
Other comments: a risk-informed approach should be pursued
if it would lead to improvements in the effectiveness or
efficiency of either the NRC or stakeholders process.
DR. APOSTOLAKIS: That's a good comment.
DR. FLACK: Yes; so they felt that that should be
added.
Maintaining or improving safety should be the
primary focus, and this gets back to the comments we just
discussed about the public citizen groups supporting only
the first of those three bullets; all other issues were
secondary. And that the costs of the public and society
need to be considered in deciding to risk-inform a program,
and it was very sensitive that the public should be
considered in any burden reduction assessment, so it was a
sense of communication. They wanted to be on board,
particularly these public citizen groups, to any kind of
reduction that would be forthcoming from the activities that
we're proposing.
So, those are four comments. Some other comments;
as Marty had mentioned, a lot of the comments were picked up
as part of safety goal discussions and not so much the
criteria, but there were these other three comments which we
thought were important enough to put forth to you: that the
area suggested for examination include -- and this is for
risk-informing -- include broad scope licensees, unsealed
sources, sealed sources, engagers in transportation. Those
were the areas that were identified as being ripe or to be
looked at for risk-informing activities, regulatory
activities.
Also implementation and associated training
requirements needs consideration; again, that was brought up
as if we're going down a risk-informed path that we need to
be thinking of training to agreement states and that the
inspection process should always be thought about while
we're doing this, and it should fit hand in glove with the
implementation. So as you go down in parallel, think about
how you're going to do this in implementation space.
DR. GARRICK: John, we have a break scheduled in
the middle of your presentation somehow. Could you advise
us on what would be the --
DR. FLACK: This would be the greatest time to
take it since we're going into safety goals next so --
DR. GARRICK: Okay; then, I think if it's
agreeable to the committee, we'll take our break right now.
[Recess.]
DR. GARRICK: All right; I want to make an
announcement because we're trying to accommodate one of the
committee members here in being present during one of our
discussions. You will note on the agenda that item seven is
a discussion of joint subcommittee protocols, and one of our
committee members has to leave prior to that scheduled time.
So what we would like to do is move that topic up to the
lunch period, and we'll have it right here in this room.
We'll break long enough to get a sandwich or something, but
we will try to, while having our lunch, have that discussion
as much as we can to take full advantage of the full
subcommittee.
So unless there's any problem with that, that's
the procedure we'll follow, and if there needs to be follow-
on discussion, we'll have that at the designated time as
item seven on the agenda.
DR. APOSTOLAKIS: But we expect to finish a little
earlier, then.
DR. GARRICK: Yes; it appears that we might be
able to finish a little earlier.
Okay; go ahead, John.
DR. FLACK: Okay; so, now, we'll move on to the
second -- what was discussed at the second half of the
workshop, safety goals, and Gary Hollohan was the one that
presented this nice, interesting phrase from one of the
philosophers: there's one thing stronger than all of the
armies in the world, and that is an idea whose time has
come, and for that being safety goals for material and
waste.
DR. APOSTOLAKIS: Now, Victor Hugo also wrote Les
Miserables.
[Laughter.]
DR. APOSTOLAKIS: We are not implying anything by
that.
DR. FLACK: Okay.
What do we mean by safety goals? To establish a
nuclear safety goal that broadly defines an acceptable level
of risk to the public and in this case also the worker,
which is somewhat different or an extension, you might say,
of the scope of reactors.
Okay; first question that had been posed as part
of the Federal Register notice was what people should think
about their perceptions of what material safety goals are
and what they would achieve and whether or not it would be
supported by various individuals, and I believe in general,
the first bullet held true, that it was -- that most, if not
all the people, at the table believed that it would be a
worthwhile endeavor. So it is getting support out there to
move in this direction.
It was generally -- there was a general consensus
that the goal should be qualitative in nature at the highest
level, and then, there was some discussion on how it would
be implemented, whether it should be quantitative or
qualitative, and I think that would have to be a, you know,
exercise or understood in the context of an application, but
there was pretty much agreement that the goal itself should
be qualitative.
DR. APOSTOLAKIS: Why is that now?
DR. FLACK: Why is it? Why would one think of it
as being qualitative?
DR. APOSTOLAKIS: At which point would the
Commission say these are the quantitative goals?
DR. FLACK: Well, I think at least my opinion
would be that it would be more on how you implement it; that
the goal itself is more philosophical in nature, and I think
you'd find that Gary Hollohan feels very strongly in that
direction as well, that the goal being a philosophical goal
by its very nature would be qualitative.
DR. APOSTOLAKIS: Well, the quantitative health
objectives were quantitative.
DR. FLACK: Well, only when you got down to the
0.1 percent; you mean for the reactors.
DR. APOSTOLAKIS: Yes.
DR. FLACK: Yes; then you were into
implementation; what do we mean by this, no more risk to the
population and then came with well, what do you mean by
that, or limited risk to population; well, then, it comes
down to, well, how do you implement it? Well, then, the
next step would be something quantitative.
DR. APOSTOLAKIS: But it was part of the safety
goals statement.
DR. FLACK: You mean at the highest level, at the
highest level?
DR. APOSTOLAKIS: Yes, I think so.
DR. FLACK: It's not quantitative; it's
qualitative, yes.
DR. APOSTOLAKIS: It starts out with a qualitative
statement.
DR. FLACK: Statement, yes.
DR. APOSTOLAKIS: And then, it says for reactors,
it should be one-tenth of 1 percent of all --
DR. FLACK: Right.
DR. APOSTOLAKIS: -- other risks, which is part of
the --
DR. FLACK: Well, okay, I see what you're saying.
You say you take it as a package deal.
DR. APOSTOLAKIS: Yes; I take it as a package. I
mean, that's a statement of the Commission.
DR. FLACK: At what time do you make that
quantitative link? Is it still at that level?
DR. APOSTOLAKIS: I remember Gary was objecting to
putting core damage frequency and surrogate goals like that
in the --
DR. FLACK: Yes.
DR. APOSTOLAKIS: -- top level statement, but
there has to be some quantitative statement even at the, you
know, in the Commission's statement on safety goals.
Otherwise, the staff will have no guidance how to do it. I
mean, you can't put that in a regulatory guide.
DR. FLACK: No, I agree. I think that when it
comes down to the practicality of it all --
DR. APOSTOLAKIS: Yes.
DR. FLACK: -- it has to be something
quantitative, and it's that the numbers represent something.
It's not that, you know, you need to achieve it as a
requirement, but it tells you this is what I think it should
be, and you can't argue with that. I mean, once you write
down 0.1 percent, everybody understands what that means. It
takes away words like being reasonable and so on. This is
it. So I personally feel strongly about that myself.
However, and I don't know if everybody agrees with
that.
DR. GARRICK: Well, maybe you've already mentioned
this, but it seems that the distinguishing words here is
qualitative safety goals versus quantitative objectives.
That's what I'm reading from the rules and regulations. The
qualitative safety goals is this general statement about it
doesn't want -- nuclear power shouldn't add any significant
risk. The quantitative objectives is when you get into the
0.1 percent.
DR. FLACK: So there is at this -- that
separation --
DR. GARRICK: Yes.
DR. FLACK: -- of the two at that point.
DR. GARRICK: So they make the distinction --
DR. FLACK: Yes, okay.
DR. GARRICK: -- by separating goals from
objectives.
DR. FLACK: Yes; okay; if that's the one way of
looking at it then. So that's the break at that point. So
you have the goals, and then, you have objectives.
DR. APOSTOLAKIS: Yes, but, you see, the third
bullet should help define the objective of the regulation.
Is that what you mean?
DR. FLACK: This was in the context of the goals
themselves would help us do the, that that would be the
mechanism.
DR. GARRICK: I suspect that that was -- oh, I
see; this is work --
DR. FLACK: These are other comments --
DR. GARRICK: Right, right.
DR. FLACK: -- that were made at the workshop, and
I think that that was made in the context they're worth
pursuing because it would help define the objectives of the
regulations.
DR. GARRICK: All right.
DR. FLACK: But then, if you say if I'm going to
sit down and develop safety goals, then, how would I develop
them? Then, you would start with some overall philosophical
statement and from there go to your objectives.
DR. GARRICK: Well, maybe the approach here is one
step at a time.
DR. FLACK: Yes.
DR. GARRICK: Maybe we ought to resolve the issue
of a qualitative goal and go from there and -- it may not be
a bad idea to adopt that as a path of progression, and if it
can be tightened or bettered or improved on, obviously,
you'd want to consider alternatives for doing that, it
seems.
DR. FLACK: Yes; I was thinking the committee
could be very helpful in letting us understand that part.
DR. GARRICK: Yes.
DR. KRESS: Well, one of the admirable qualities
of the PRA and a risk assessment is it's quantitative. And
if you're going to make full use of that attribute, you need
to have quantitative risk goals, and I don't know how bound
you are to workshop feedback. I mean, these are things you
take into consideration.
DR. FLACK: That's right.
DR. KRESS: But I certainly would say somewhere
along the line, you need to have quantitative goals that are
-- that are expressed in risk terms related to PRA or risk
type activities. Just almost seems like you can't function
in a risk-informed world without it.
DR. FLACK: Very well.
DR. KRESS: Even 1.174 has quantitative things in
it that they use.
DR. FLACK: That's true; I think most methods that
you would look at -- I'm thinking about them -- ISA, PA, you
know, barrier, hazards barriers, target analysis; that sort
of thing, all involve some sort of quantification. You're
ending up with a quantified numerical result at the end.
And then, the question is how do you link that numerical
result to some higher level goal that you're trying to
achieve, and, you know, if we're thinking about risk of the
public out there, which is basically where it comes down:
how much risk -- the fact that we're using nuclear materials
means that we're going to expose the public to some risk. I
mean, they just can't avoid that.
So the question is then how much is acceptable
risk, and that's where you begin to get into what percent
are we talking about to the public and then the worker, for
that matter, because we're dealing with both of these more
in this arena, and structuring it that way so then, the
natural tendency would be, of course, once you come down to
a percentage, then, you're there; essentially, this is what
we think. And then, you can use different methods on seeing
where you lie relative to that goal and what you could do if
necessary to meet the goal but not as a requirement but
things that you could do to improve the regulatory process
in doing that.
DR. GARRICK: Tom, what about another thought
process here? Suppose we took this in a kind of a phased
approach and said, well, the first thing we maybe ought to
be doing is doing some risk assessments, some quantitative
risk assessments and seeing what kind of results we get,
what constitutes a rational form to put the results in, et
cetera, et cetera, and give some experience in developing
this measure before we necessarily freeze on how we want to
calibrate it?
In other words, you can always calculate the risk
without a goal. You don't need a goal to calculate the
risk. But you learn a great deal in the process of doing
risk assessments about what you can do and what you can't do
about what the contributors are, about what the
uncertainties are, and it's possible that that kind of
information could be extremely beneficial in the calibration
process.
DR. KRESS: Yes; I support that very strongly, and
I'll tell you why I view a goal or an acceptance criteria as
a completely separate entity than what you're talking about.
DR. GARRICK: Yes.
DR. KRESS: If you do what you said first, it
tells you what's possible.
DR. GARRICK: Right.
DR. KRESS: And that odds somehow enter into your
decision on what a goal or acceptance criteria you might
have. It tells you, you know, if your risk assessment of
some sort of activity gives you a number, and you set an
acceptance criteria that's impossible to achieve --
DR. GARRICK: Right.
DR. KRESS: -- well, you haven't done very much.
DR. GARRICK: That's right.
DR. KRESS: And I think it helps guide doing it
both ways.
DR. GARRICK: Right.
DR. KRESS: But I think you set -- I mean, the
basis behind acceptance criteria stand alone, in my mind,
and can be developed as a separate activity, but you've just
got to be careful you don't put a value and shoot yourself
in the foot, and your activity helps keep you from doing
that.
DR. GARRICK: Yes.
DR. FLACK: Okay; some of the other comments that
safety goals would help communicate what it is we're trying
to achieve, certainly, articulates that to the public. Then
came a lot of discussion about whether it should be
application specific versus, you know, global that captures
all of the different areas, and we could talk about that a
little bit more when we get to the case studies, but many
thought that it would probably be more than one goal that we
were talking about.
That the development, of course, would be a long
and involved process, and people recognize that. It wasn't
something that needed to be done because -- at the moment,
in a short period of time, to do something. But it's
something that I guess people felt they were more patient,
they were more patient with and that it was an evolutionary
kind of goals that would be developed in that. It would be
a long process. And that was satisfying, I think.
The relationship between safety goals and
strategic goals; we talked about some of that before. It
really needs to be articulated what we mean by strategic
goals, what do we mean by safety goals, performance goals
and how they all relate to one another was a comment that
was made. And so, these were all in the perception of what
we would use or envision safety goals to achieve and the
benefits from doing that.
The next question focused on the developmental
process of the goals themselves and that we should try to
understand the goals underpinning our current regulations as
part of that developmental process; to use case studies; to
develop safety goals and then, while doing the studies,
actually capitalize on their insights. So that leads us to
development of risk-informed approaches in parallel with the
safety goals, which is something that Marty had mentioned
this morning, so we're not really waiting for the safety
goals to be developed; there's a lot to be gained just from
working through the process and seeing how risk plays out
within that context.
There was some sensitivity to the desire for
consistency with and among agreement states and that there
may be different values across the different states, so it
may not be that easy just to have them all agree on what we
mean by a goal, but this was one of the issues that kept
coming up at the workshop.
DR. GARRICK: Were the agreement state
representatives vocal on the issue of safety goals and
probabilistic approaches? They have been in the past; I
just --
DR. FLACK: Vocal in the sense of --
DR. GARRICK: Vocal in the sense that most of them
were not favorably disposed toward doing PA probabilistic
performance assessment, for example.
DR. FLACK: Oh, well, I guess we never got down to
the level of where, you know, to discussions of the tools
and the methodologies --
DR. GARRICK: Okay.
DR. FLACK: -- in order to implement it. It was
more at the philosophical level, whether we need goals or
not, so maybe that may become an issue. I know that
resources, there's always a problem, and it came also up in
a context of well, if we go ahead with this, what about
training? How do we make it work.
DR. GARRICK: Okay
DR. FLACK: So, yes, I think that's the next level
down; that's something that we're going to need to be
concerned about.
And that gets to the next one, which is ensure
regional and local involvement, and that is, again, trying
to lead to goals that are consistent across the different
regions and localities; to certainly hold workshops, public
meetings in the diverse regions and involve stakeholders
early in the process, so these are things, again, that they
want to know what's coming; they want to be involved in. So
there was a lot of support in that regards.
Okay; what factors -- next view graph is what
factors need to be considered during the development of the
safety goals for materials and waste? And there's some
really sticky ones here, I think, the first one being
national versus local values again, the diversity across the
nation with respect to that. And then, came the question of
ecological risk, and that was discussed this morning in the
context of reactors: where are we going here that's
different than reactors with regards to that risk
contribution?
And then, we're looking at operational versus
accident risk, so you're looking at these two things
together, where with reactors, it's primarily accident risk
that we're dealing with.
And then, you have worker and public risk. So, we
look at the worker and what the worker is exposed to with
respect to his job and the risks that he would normally be
exposed to as part of that versus the public, who is outside
that area and what would they normally be exposed to, and
then, the goals would certainly be tailored differently
between the two, it would seem.
Harmonization among and with other agencies; that
was something that came up this morning about the other
different agencies and having different, possibly different
objectives. And then, there's a question of legislative
requirements and what legal ramifications there are in
developing such goals, and we'll probably hear a little bit
from Bob on the next one: risk to future generations is
sort of associated with waste disposal, so I'll let -- Bob
Bernero is here, and he will certainly want to discuss that
a little bit further.
Also, the risk associated with theft, sabotage and
diversion of nuclear materials. Now, we have a different
type of risk, the risk of diversion of materials that's
possibly to be considered in the scope of a type of safety
goal.
And then, you have the risk associated with
chemical toxic releases to the environment as part of the
activities that go on at these facilities, for example. And
then, there's always the hidden considerations that may be
embedded in the regulations that we have to be sensitive to
when we look at the regulations and say this is what led to
X. There were some considerations that were obvious, but
then, there may be others that were hidden in those
decisions that got us there, so it's not going to be a
simple process. There are quite a number of factors that
are going to be involved in considering safety goals for
this area.
On the next slide, we ask the questions about the
analogy between the reactor safety goals and the development
of material safety goals, material and waste disposal and
safety goals, and clearly, at one level, there is an
analogy, and that is the radiological risk to the public,
although the criteria might be different: what risk are you
exposing the public to?
So, I guess that's as far as it goes as being
analogous. The rest are the worker risk, the ecological
risk, the risk for diversion of materials; these would all
be different. These are somewhat different areas that are
not presently being captured by the reactor safety goals at
least in the implementation for reactor safety.
And then, five: the question of whether these
safety goals should be overarching, or there should be
safety goals in each of the areas, and this led to
discussion, and it seemed that there was a general consensus
that one goal wouldn't capture everything; that there would
be a need for separate goals and that we should use these
case studies, which I'll get into in a moment, the different
areas to explore safety goals in these different areas.
But, you know, at the end, there should be
something that brings them all together, and so, although we
may go down different paths, once we're there, we may find
that there is a next level up that we can kind of pull these
goals together at some higher level; it certainly can be
entertained, but it may not be so easy to start from that
point.
DR. KRESS: The reactor safety goals are -- takes
precedence to the mean values, which implies to me some sort
of statement about the uncertainties. When you choose a 0.1
percent value and say this in the assessed version of this,
you want it to be the mean value at this thing, what you're
implying is that given the level of uncertainty in that
assessment, this is an acceptable value to you given that
this is a confidence level that you're willing to accept.
Are you going to have some thoughts about confidence levels
or uncertainty in terms of these goals? Are you going to
say -- are you going to stick with this mean value concept?
How are you going to factor that sort of thinking into that?
DR. FLACK: And the question applies, you know,
it's hard to answer a question like that without an
application. I would say, of course, the mean value is the
preferred value just from the mathematical beauty of it, and
it captures the thoughts on your uncertainties and so on,
and when you deviate from that, you're using, you know, a
certain degree of judgment as to what, okay, if we're going
to go to something else, why are we going to something else?
DR. KRESS: Well, I personally don't view the mean
value as any unique position on the distribution. It is a
unique position because it's the mean, but it doesn't have
any special meaning to me other than that.
DR. FLACK: The mean's the mean.
DR. KRESS: Yes, it's the mean.
DR. FLACK: Yes; I recognize that.
DR. KRESS: But, you know, median is just --
DR. FLACK: That's another concept.
DR. KRESS: And any 95th percentile or anything
is, you know, just as unique.
DR. FLACK: Well, whatever measure is chosen, it
needs to represent something, and it's in its representation
that it becomes important, and it's not so much that we want
to try to achieve this value by comparing the mathematical
models and the results of those models to it so much on a
numerical basis, but it's something that comes out of how we
try to articulate our view on safety. What are we doing?
What does it represent as a value? And it leads you back
again to the percentage. When we talk about a certain
percentage of risk to the public, and then, the question is
well, how do you demonstrate that what you're measuring is
the risk and that it is indeed a certain percentage of what
the public is exposed to?
Well, you're comparing again two values. It's not
just a value; it's a comparison of values. And so, when
you're comparing values, one has to be more or less
consistent with that comparison, and comparing means is one
way to do it. There may be other ways of doing it, but it's
a good question that really needs to be fleshed out as, you
know, part of the studies, I think, that needed to be done,
and the models that are developed and how we represent risk
out there that the people in the public or the worker might
be normally exposed to, so it's coming to grips with that
within that context.
So any other questions on factors to be
considered?
[No response.]
DR. FLACK: Oh, I'm moving ahead already on this
one. Safety goals -- oh, okay; five and six, I think we
discussed.
How resource intensive -- we mentioned that
earlier, that it's too soon to tell exactly how resource-
intensive this project is going to be, but it certainly will
be long-term and involved. And one comment is, well, try to
do the easiest task first. Go after the low-lying fruit, so
you can be somewhat efficient and effective in the way that
you would attack the problem and also that as part of the
resources that NRC needs to again consider -- I must have
mentioned this three or four times already, the training
needs for the agreement states. So it will not be a simple
task.
Number seven, what will ultimately change if we
have goals from what we're doing now was a question we had
posed out there, and there were comments. Most people
believe that by putting goals out that we would likely get
safety improvements and relaxations where requirements do
not contribute to safety, so by knowing how safe is safe
enough is a two-edged sword there, but people believed, and
I think most people believe that it would make us look at
things differently and things would change one way or the
other.
It would certainly help consistency regarding the
regulatory process because people then understand what the
goals, the objectives of the registered, what we are trying
to achieve as a regulatory agency. There is potential for
savings, since you will focus resources on those areas that
will most help you reach the goal, and it certainly would
enhance communication by allowing the agency to express
their expectation of what is safe enough. So those were the
comments that were generated on the seven.
And that pretty much covers the spectrum of
comments that were mentioned at the workshop with respect to
those questions we had asked.
So if there's no other questions on those, I'll
just mention the case studies that were suggested, and these
are the different areas in which we were entertaining
further work to define -- for testing the screening criteria
and the value added in risk-informing a focused area and in
developing specific safety goals, so again, this would be an
in parallel kind of activity. One area is, of course, waste
disposal, high-level, low-level and decommissioning.
DR. APOSTOLAKIS: Is that high level waste
disposal area risk-informed already?
DR. FLACK: Is it already risk-informed? Well, we
could ask Chris that question if Chris wants to entertain
it. I would think so. I would there there's a great deal
of risk already embedded in that regulation. It would just
be a matter of going the next step up with it and saying,
well, you know, what fraction of the risk to the public are
we talking about and whether that's getting us there. I
don't know about specifically whether we could define it as
a goal. I mean, there are certain requirements in the
regulation that are being established, and presumably, if
you meet those regulatory requirements, you would meet some
goal.
But I don't know; Chris, can you shed any light on
that?
MS. LU: This is Chris Lu. I'm also a member of
the risk task group. The final part 63 now is in front of
the Commission for consideration, so I can talk from the
proposed rule that we put on the street. We do require, for
post-closure period, we do require a performance assessment
to be conducted, and in the proposed rule, we are looking at
the mean peak dose over 10,000 years as the compliance
point.
In terms of the safety goals, during the workshop
that we had last week, a couple of the participants pointed
out that since we do have a risk-informed performance based
rule, we can imply what is the safety goal from that using
the regulatory criteria and requirements.
DR. GARRICK: So the answer to George's question
is yes.
DR. FLACK: It may very well be.
DR. GARRICK: It seems.
DR. APOSTOLAKIS: This is the most risk-informed
activity in the NMSS, isn't it?
DR. GARRICK: Yes, yes.
DR. APOSTOLAKIS: At this point, and the EPA
criteria are also or used to be.
DR. GARRICK: I'm very top-down oriented, and as I
look at that list, I kind of come out that as far as safety
goals are concerned and risk assessment is concerned that 90
percent of the problem is number one. That's the bad news.
The good news is that we're well advanced in number one over
all the others in terms of the use of risk based methods.
You know, if you think about it, large process
facilities cast some packages and associated transportation;
there's no reason why we can't basically use the reactor
risk assessment technology to deal with those kinds of
problems. I also think that on medical uses and fuel
sources, the NMSS with the studies they've done recently are
in pretty good shape in terms of understanding what the
risks are and have done a very good job, in my opinion, of
pointing out the relative contribution of operational risk
and accident risk and concluded the thing that a lot of us
in this business have been saying for a long time, that the
real risk is operational risk. It's not accident risk.
So that kind of brings us back to as far as safety
goals are concerned and what is the real threat to the
public and the concern, and the achilles heel of the
industry is still number one. The rest is kind of no, never
mind almost, and I sure hope that our resource allocation
and our problem resolution emphasis reflects on our state of
knowledge about that. One of the questions this committee
asked very early on is that NMSS should tell us, on the
basis of their expertise, what they think the real risks
are.
Well, I think they've done a pretty good job of
that with respect to sealed and unsealed sources and medical
uses of isotopes and with respect to the by-product problem.
Beyond that, except for the repositories, the problem can be
handled in a very -- in a fashion very similar to the
reactors in the sense that it can be based largely on
reactor risk assessment technology. So -- and when you come
to the repository, then, the question of differences there
become critically important. It's not an accident issue on
repositories. It's a long-term performance issue. And I'm
not sure we've gotten that message out to the public.
I could almost argue there's not a safety issue,
and the reason there's not a safety issue is that we have
time to interdict and to intervene. We don't -- we are not
caught by surprise by a big accident. It's a long-time
deteriorating, degrading process, so the driver as far as
public risk is concerned on repositories is the denial of a
resource, not public safety. Now, we may eventually come
around to that, and we're not there yet, but there is no
public safety issue, because as soon as we detect that
there's something in the water, we do something about that.
As soon as we detect that there's something in the food, we
do something about it, and we have years and years of time
to do that.
So the real issue there is denial of a resource,
and it's probably the reason why EPA is so adamant about the
groundwater standard and protecting it now that they have a
standard. If they didn't have a standard, maybe there would
be a much more rational process developed here. But I think
that -- I'm hopeful that when we get around the safety
goals, these very activity-dependent issues are getting into
account and the differences, and I see the problem centering
principally around, still, number one, because I think for
the most part, we can piggyback what we know already except
for maybe the establishment of some sort of safety goal to
use as a rule.
So I'm hopeful that the thought processes here are
taking into account such things as in risk assessment, the
whole goal is to be realistic, and if you're realistic, the
issue is not public safety on waste disposal. It's resource
denial. And because you've got an opportunity to intervene,
to interdict, you don't even call it emergency response,
because it's not an emergency. It's something that happens
very, very slowly, and you can detect it very, very, very
early, and the opportunities are tremendous for corrective
action.
So I don't know if any of that kind of dialogue
came out in this workshop, but I sometimes think we confuse
the public because we present these issues sort of as if
they're similar, and I'm talking about waste disposal versus
reactor safety, and the differences are extreme.
DR. FLACK: Well, no --
DR. GARRICK: And they give us a great opportunity
to recast the problem and deal with it in a much different
way.
DR. FLACK: No, I think that's the reason why we
have these five areas. That's not clearly that it would be
similar to one of the others.
DR. GARRICK: Yes.
DR. FLACK: It definitely needs to be looked at in
its own right, and I think that was one of the areas where
it was identified as a specific area. But I think what the
message is is that maybe it's more in the vein of public
communication already what we have. We don't need anything
new. We need to communicate what we have better and that
it's really through the implementation, maybe, of some
performance measures that we will know when things have
deteriorated, and we can take those actions, and that's a
defense-in-depth mechanism, actually.
DR. GARRICK: That's an action that's no different
from today. We don't -- we don't plant crops in
contaminated fields today. We measure; we know what we're
doing. We don't use a water supply that's polluted or
contaminated, and I don't think we're thinking that way.
And that's what we're talking about here, and that's all we
have to do to keep it from being a safety issue. So I'm
just throwing out this kind of notion that it's not a safety
issue. It's an environmental impact issue, and that's all
it is for number one.
DR. FLACK: Yes.
DR. GARRICK: And yet, number one is 90 percent
plus of the reason why there is an ACNW or why there is
anxiety in the nuclear industry about the waste and that we
can't solve the waste problem.
DR. FLACK: Well, yes, that may be true.
Number two is not so far behind, though; I mean,
there is a lot of concern in that area as far as
transportation and so on.
DR. GARRICK: It shouldn't be, though.
DR. FLACK: Yes.
DR. GARRICK: It shouldn't be, because we know how
to analyze transportation, and we've done a tremendous
amount of field work in transportation. We've just done a
lousy job of making that field work available. We have run
trains into walls; we've run trucks into trains, and we've
damaged casks from every angle and perspective we possibly
can. And the public does not know that. They have not seen
that information, and they have not seen it organized and
compiled and structured in a way that communicates what we
do know about it.
I think transportation is one of the biggest bogey
mans that exist in this whole arena and that we as
technologists, as agencies, have failed miserably in
conveying what is known about transportation risks, and
we're spending billions of dollars as a result of it, not
only in the nuclear field but in other fields as well. So
we, regulatory agencies and technologists have failed
miserably in communicating to the public the transportation
issue.
DR. FLACK: Yes; I think there's an activity now
to plain English issuance of that work that had been done on
those transportation studies and the work that, I guess,
continues to go on in demonstrating that the risk is small.
DR. GARRICK: Yes.
DR. FLACK: But I -- you know, I think what your
concern is being appreciated by the staff and moving that
direction, but, you know, maybe they should have been there
earlier, but the plain English is supposed --
DR. GARRICK: No, what I'm trying to do is cut
through some of the things here, and, you know, I sometimes
think we treat these things as if they're equal when, in
fact, the differences are extreme and that if we fixed one
of these up there, you know, 95 percent of the problems
would go away.
DR. KRESS: I agree, and I think when you develop
some sort of risk acceptance criteria or safety goal, and
for the waste disposal area, I think it has to be an
acceptable frequency of a release exceeding a certain amount
of activity at a particular time. I think you have to have
all three of those things: an acceptable frequency, a given
amount of activity and at a given time. You have to
discount 10,000 years from now to present cost some way if
you have a cost criterion involved in it.
So it does -- I think you're exactly right, that
it impacts on how you -- what you say is an acceptable risk
and what you define as your risk is the risk of exceeding a
certain frequency of release at a given time.
DR. HORNBARGER: Just for the record, I want to
disagree with one thing that John said, and that is that
although I agree with much of what he said about the
differences, I think that one would have to be careful
saying that it under no circumstances would be a public
safety issue, and one of the comments he made was for
example, we don't drink polluted water today. This is
patently untrue if you look on a worldwide basis. One
recent example that has made the news is the use of a very -
- a water supply in Bangladesh by a very large number of
people, and we know full well that it's contaminated with
arsenic.
DR. GARRICK: And my point there George --
DR. HORNBARGER: But there's no alternative.
DR. GARRICK: My point there, and I've been to
Bangladesh, and I know that.
DR. HORNBARGER: Yes.
DR. GARRICK: But my point there, though, is we
have a choice. We have a choice to not drink that water.
DR. HORNBARGER: Yes; the people in Bangladesh
don't have much of a choice.
DR. GARRICK: Well --
DR. HORNBARGER: That's my point.
DR. GARRICK: We certainly would have a choice to
not consume radiation contaminated water.
DR. HORNBARGER: Well, I mean, it's easy to say
that the people in Bangladesh don't have to consume that
water. The point is they don't have an alternative. And
your point is that people in Los Angeles, for example, can
drink bottled water. That's fair enough. So it has to do
with what you envision the wealth of the society being at
the time, and that's very hard for us to say with certainty
that thousands of years from now, people in Nevada would be
able to drink bottled water.
DR. GARRICK: Well, I know it's an extreme view,
but it's a view I make to make a point, and the point is
that the opportunity exists to prevent it from being a
problem, whereas maybe if you had the right kind of reactor
accident, you wouldn't have that kind of opportunity.
That's really the only point.
DR. FLACK: Okay; so, these, again, are the five
areas that had come out as areas to be pursued possibly
using case studies to better understand the regulatory
process and to develop safety goals as part of that process.
No other questions, I'll move ahead to the last
slide I have, follow on activities.
So we're still digesting all that has come out of
the workshop, and we still have an open comment period, so
we're not at the stage where we have a fully-developed plan,
but that's where we're headed. As far as follow-on
activities, we're going to inform the stakeholders and
solicit comments by issuing a workshop summary with the
transcripts and making those transcripts available to
everyone. I believe we will be getting a copy for the
committee as well.
Draft a plan; that would be something that we're
planning on doing within this fiscal year. We'll develop a
plan, draft a plan and then, of course, interact with the
group, the NMSS steering group and so other stakeholders as
part of the development of that plan and then to inform the
Commission and the ACRS, ACNW of the plan and then what the
next steps will be. So, we're hoping to have that developed
as part of this fiscal year.
So, I would say we're in a stage now where we're
about to be off and running. So, with that --
DR. GARRICK: Well, that's great. We may have
time to hear from Mr. Bernero after all.
DR. FLACK: Yes, great.
DR. GARRICK: But let me, before I do that, make
sure that the committee is -- doesn't have any pressing
questions for John.
[No response.]
DR. GARRICK: No; thanks a lot.
DR. FLACK: Okay; thank you.
DR. GARRICK: It was very helpful.
DR. FLACK: I appreciate it.
DR. GARRICK: Bob?
DR. BERNERO: I promise to be brief; nearly
impossible.
[Laughter.]
DR. BERNERO: There is a two-page handout that I
brought a bunch of copies of, and I hope you all have it.
The handout, titled a process for risk-informed regulation
of activities, is intended to amplify the recommendations I
made at the workshop just discussed on April 25 and 26th,
and just before I remark on what the handout says, I would
ask you to recall that 20 years ago, when the reactor safety
goals were being developed, there was an explicit statement
in plain language of what the safety objective was, and it
varied in expression, but it was essentially that the risk
to those people who lived closest to a reactor would be
negligible compared to the average risk of accidental death
or cancer death, and that led to the hierarchy of one-tenth
of one percent and, you know, what database you're going to
use, and there's not that much sensitivity, because the
Commission could have argued for 10 percent, for 1 percent,
and it chose the very conservative value one-tenth of one
percent, and I can attest from my own participation in it
that it chose one-tenth of one percent because available
risk assessments said yes, that can be met, that strict
standard. It was holding the nose to the grindstone,
really.
The fundamental point that I try to make with this
handout is that one needs to start with a plain language
qualitative statement of the safety goals or objectives, and
a word of warning: in the NMSS arena, one has to do this
unique to the practice, a term often used in material
regulation as a practice. That could be radiography; it
could be bracha therapy; it could be low level waste
disposal, but it's a practice that involved the disposition
of radioactive material.
I suggest in the handout a way to approach the
statement of objectives for waste disposal, and one of the
alternatives -- and I've used it before -- no person in
future should suffer radiation exposure from these wastes
that we would not find acceptable today. Now, that's an
exposure statement. It could also be couched as a -- or
couched in risk terms or supplemented by a risk statement,
and more on that in a moment.
I suggest that in each arena, there needs to be a
plain language qualitative statement of objective. Then,
one can develop measures of protection, still staying fairly
close to qualitative language, not yet going into
quantification, and I suggest, using the example of waste
disposal, the three measures of protection.
DR. APOSTOLAKIS: Before you go to that, Bob, you
have another example in your plain language paragraph:
releases from this isolated waste should do no harm to
anyone. Doesn't that imply that there will be releases?
DR. BERNERO: Oh, yes, definitely.
DR. APOSTOLAKIS: And we know that that's a fact?
DR. BERNERO: Oh, yes, yes.
DR. APOSTOLAKIS: We're not trying to prevent
those?
DR. BERNERO: Yes; there's virtually no guarantee
of total containment for the what? Maybe 20 half lives of
all the isotopes. You know, we're quibbling about isotopes
like iodine-129 with semi-infinite half-lives, you know, so
20 half-lives of iodine-129 is, I don't know, 300 million
years or something like that.
DR. APOSTOLAKIS: I still think that your second
example is better, though.
DR. BERNERO: Oh, I'm not laying claim to any of
these, and I point out they don't have the risk terminology.
But the three measures of protection that I think are
expressing the idea I'm trying to develop; the first one is
the likely, the expected or the predicted release results in
exposures that are clearly acceptable. In other words, if
you decommission a reactor and leave a pile of rubble that
has detectable or measurable concentrations of
radioactivity, you are looking for your best estimate, your
most likely outcome to be clearly acceptable: no harm. You
wouldn't do it otherwise.
But then, you can go to a second, a risk
statement, taking careful account of uncertainties in
modeling, in data, in scenario development that taking those
uncertainties into account, the estimates to the persons in
the vicinity will be within the level of public exposure
risk that we find acceptable today. Now, there's a little
trick here: when you speak of the future exposure, you're
forced to consider a predicted exposure or the risk of
exposure, whereas what we find acceptable today is a
measured as well as a predicted exposure, and that's an
important difference.
And then, lastly, the third measure of protection
I would suggest is that go beyond the risk analysis; probe
further for weaknesses, whether it's with an importance
analysis or some other measure, because in waste disposal or
in other material practices, there are factors that do not
lend themselves to robust risk assessment. Radiography, for
instance, I think you'll hear more about it later; it's so
crucial to recognize that the individual radiographer is at
the heart of the problem, and modeling the radiographer and
his or her behavior is very difficult.
So the handout goes on into quantitative measures,
and the first thing I try to point out on the second page;
you've heard from me before on a ladder of exposures, going
from the high exposure down or from a low exposure up, and I
list only four rungs on the ladder here, from 1 millirem to
1,000 millirem, and the point I'm trying to make is we
glibly speak in risk assessment -- this is performance
assessment for waste disposal -- of calculating a mean
value, taking due account of the uncertainties in data,
scenarios, models and so forth. But no one ever speaks of
the uncertainty in the threshold of acceptability. There is
no doubt in my mind people speak of 25 millirem or 15
millirem or 4 millirem as a threshold of acceptability as if
to say below that number, I'm happy; I sleep well at night.
If it goes above that number, I'm unacceptable; the
situation is unacceptable.
That's wrong, and all you have to do is climb the
ladder one way or the other, and you see that. The standard
is uncertain because of the habitual choice of very low,
conservative numbers that make us talk about what I consider
indistinguishable things like 25 millirem versus 15 millirem
versus 4 millirem. To me, it's 10 millirem. There is no
distinction over this order of magnitude. One should only
speak in orders of magnitude.
And so, if you do performance assessment as risk-
informing, going back to the first three things, the first
three measures of protection, I would see that as a set of
findings of acceptability, not excluding the other
deterministic findings like human intrusion being dealt
with, things that don't lend themselves to risk assessment.
But for the risk information of decisions, the findings can
be something on the order of measure number one is the best
estimate; measure number two is the mean value of a good
performance assessment; and measure number three is the
suspicious probing for weakness in the analysis, recognizing
that there is a healthy difference -- I shouldn't say
healthy -- a substantial difference between what we're
stating as the standard of acceptability and what we might
recognize as a standard of tolerability.
DR. GARRICK: Is what you mean by number three the
whole curve?
DR. BERNERO: No, it's more than that; it's
probing the process itself for, you know, I've always
thought things that can bypass the event tree, that can
render the systematic analysis weak. You should be treating
in the, like, adequacy of site characterization; that's an
uncertainty that should be treated in a good --
DR. GARRICK: So it's, in the language of George
and Tom here, it's the unquantified uncertainty.
DR. BERNERO: Yes; yes, the things that you really
don't feel comfortable handling, and what I'm probing for
here is some systematic method to probe for weakness and to
look for the edge of the cliff, because the one thing you
don't want to do is have an unquantified uncertainty that
lurks and may likely give you catastrophic results. I have
to disagree with you, John, on what you were saying earlier
about waste disposal about if it leaks, we'll detect it, and
we can interdict it.
DR. GARRICK: I said that option exists.
DR. BERNERO: Yes, yes, that option exists, and I
would argument that in the plan language statement of no one
in future will suffer exposure or risk or whatever the
Commission or the regulator would choose to say that there
has to be a statement of willingness to depend on
stewardship or monitoring or even budgeting in the future.
Right now, I spend a lot of my time looking at the
Department of Energy's remedial action alternatives, and
frankly, they're driven by the availability of funds and
other factors that make it highly desirable that one could
have passive protection.
DR. GARRICK: Yes; well, we could debate this for
a long time, and this is not the place to do that, but the
point I was making is that it basically is no different than
the challenge that the human race has of dealing with any
environment. There's nothing peculiar about that
environment.
DR. BERNERO: Yes, and you're right in that, John,
and it's just that in nuclear waste technology, as against
contaminated waste technology or anything, there has been
this espousal of an objective to do it passively without
human intervention for whatever period of time and simply
assessing at some interval -- 10,000 years or 500 years or
whatever -- how successful has that been, or how successful
would we predict that to have been.
DR. HORNBARGER: Bob, just a comment. You used
the 25, 15 and 4 millirems, and we all know that those
numbers have some associations, and I would just point out
that the 4 millirem, if it's interpreted as radionuclide
specific, may, in fact, be one or two orders of magnitude
lower than 15 to 25.
DR. BERNERO: Yes, yes, if you use ICRP-2 and all
of that, yes.
The point I would make on waste disposal, my
understanding -- I didn't participate or listen, but in the
Maine Yankee decommissioning, I understand that there has
been heated debate about whether 25 millirem is sufficiently
protected vis-a-vis 15 millirem, and that, to me, is
terminal bottom line disease.
DR. GARRICK: Well, hasn't the state already put
their limit on it of 10?
DR. BERNERO: Oh, yes, most of the states do at
10.
DR. GARRICK: Yes.
DR. BERNERO: Yes; South Carolina, New York State,
and I wasn't, you know, ruling out any. But the -- I think
to quarrel about the level of protection provided by 10
versus 15 betrays that the argument is in the wrong forum,
you know; the point has been missed. That's not risk-
informed.
DR. KRESS: Bob, I'm interested in your comment
about comparing measured risk versus predicted risk as being
comparing apples and oranges to some extent, and with
regard, with respect to the high level waste repository, I
would expect an acceptable risk 1,000 years from now ought
to be much different than an acceptable risk tomorrow or, I
mean, 10 years from now. How do you deal with that in
acceptance criteria? How do you factor that kind of time
consideration into a risk acceptance criteria?
DR. BERNERO: It's factored in by the underlying
assumption that there will be no change in the vulnerability
of the human body to radiation exposure and also no
significant change in the ability of medical science to cure
cancer; that radiation induction of cancer and the relative
fatality from cancer will not change. There has been
substantial change in -- just in my career, I recognize, but
the fundamental assumption is today's standards will be
appropriate standards to judge the future.
Now, as far as oversight is concerned for
hazardous waste or for radioactives in hazardous waste at
circla sites, the institutional mechanism is fix it to the
appropriate standards, and for circla, come back every 5
years and look at it; for RCRA, come back every 30 years and
look at it, and we'll talk about it then. That's a vastly
different thing. The only place in radioactive waste that
we encounter something like that is in the rather bizarre
case of uranium mill tailings. If you ever get a chance to
go look at it, uranium mill tailings are monitored annually
after site closure with NRC oversight, and people go out
there with shovels and tree planting to fix them.
DR. GARRICK: Bob, it's our fault -- I realize it
-- but your two minutes are up.
[Laughter.]
DR. BERNERO: Thank you.
[Pause.]
DR. RUBIN: Good morning. My name is Alan Rubin,
and Bob is always a hard act to follow, but I'll do my best.
I'm a section leader in the probabilistic risk analysis
branch of the Office of Research, and I've had the pleasure
and the opportunity to have a number of interactions with
the ACRS before, but this is my first time to have some
interactions with ACNW and the joint subcommittee.
The subject I'll be presenting will be one of the
applications of PRA for analyzing the risk from dry casks,
and let me first mention that this is an effort that
involves a number of participants both in the Office of
Research and in the spent fuel project office of NMSS.
DR. KRESS: Is this on site at reactor plants
you're talking about?
DR. RUBIN: This is on-site storage, dry cask
storage.
DR. KRESS: On-site storage.
DR. RUBIN: Dry cask storage, yes; I'll get into
the scope and the nature of the program as well, Tom.
The participants, the many participants from the
Office of Research are myself, Ed Roderick and Chris Rider,
also in the probabilistic risk analysis branch; Ed Hackett
in the materials and engineering branch and Charles Tinkler
in the safety margins and systems analysis branch, and they
are with us today.
The time frame that we're in now in developing the
plan, it's a very good opportunity for us to get feedback
from this joint subcommittee on our approach to the plan,
which I will be presenting today, so we welcome this
opportunity to get your comments.
For an outline of what I'll be going over, I'll
first present the objective of the project itself. I'll go
over the scope as we see it as well as the major planned
tasks that are included in the program plan, which will
include discussion of potential accident initiators; how we
plan to screen those initiators; looking at various
initiating event frequencies and sequence frequencies and
consequence and risk quantification, and I will also discuss
the present schedule and status of our plan right now and
overall program.
We heard presentations earlier this morning at a
fairly high level, sometimes philosophical level on safety
goals, and this time, we're going to get into a specific
application of PRA, and the objective of this risk analysis
is to do a pilot PRA for a specific spent fuel dry cask
storage system at a reactor site, and this is a first of a
kind, and it's got challenges being a first of a kind, which
we have encountered; we need to overcome some of these
challenges in carrying out the program.
In terms of NMSS, what we expect to provide and
NMSS hopes to get out of this program is to get information
in several areas, to see whether there's a need to do
additional site-specific PRAs; to see whether there's a need
to develop any additional data or methods for doing PRAs for
dry cask storage and to see whether some additional analysis
would be required. And in the longer term, NMSS would like
to be able to use this information to provide input to the
safety goal assessment; to risk-informing 10 CFR Part 72 as
well as for the inspection programs for dry casks.
[Pause.]
DR. RUBIN: The participation in the program
involves all three divisions in research, and it's a team
effort: division of risk analysis and applications has the
lead for the systematic analysis and integration of the PRA
as well as coming up with frequency and probabilistic
assessments; division of engineering technology will
participate in coming up with analyses and engineering
assessments of the materials of the multipurpose canister
and the cask as well as the overpack structure, and I'll
give a figure later on, a diagram to tell you a little bit
more about the cask itself and develop some thermal
analysis.
Division of systems analysis and regulatory
effectiveness will provide assessments of the radiological
release and dose assessment to the public in the event of an
accident. It's very important that we coordinate this
program very closely with the spent fuel project office in
NMSS, and we've done so up to this point, and we expect to
continue to do so. This is in terms of both developing the
program plan itself as well as carrying out the plan.
We also anticipate that we may need some
information from licensees to provide dry cask design or
operational data, in effect, perhaps some analysis that
supports some of their information, their safety evaluation
report. We expect that we will also need some contractor
support in the area of human reliability analysis for -- to
address the handling and transport aspects of transporting
the fuel and the cask itself and perhaps other additional
contractor support as well.
DR. APOSTOLAKIS: So you can do everything else;
start your thermal analysis, everything except human
reliability analysis?
DR. RUBIN: Well, we know that we may need some
analysis as well. It's going to depend on what's available
from the contractors, from the -- not from the contractor;
from the analysis already done for design basis accidents
analyses by the vendor, by the licensee, and see whether we
can extrapolate that or whether we need to do some
additional analyses, and we're wrestling through right now
to see whether we can do that in-house or we'll need
contractor support.
DR. GARRICK: Did you say that some of the same
team members are involved as were on the spent fuel pool?
DR. RUBIN: Yes; that is correct; same names, same
guilty parties.
DR. GARRICK: Yes.
DR. RUBIN: That's the team. Let me go over
what's entailed in the scope of the project, and in the
recommendation from NMSS, we select the whole tech high
storm 100s dry cask for analysis for this pilot PRA, and
that's based in the potential usage of this dark cask as
well as availability of data that's been submitted in the
licensee's application. It's the different modes of the
analysis, the analysis itself will include handling of the
fuel and the dry cask; onsite transport, transport of the
cask to its storage pad as well as the long-term storage
onsite. It does not go beyond that; it does not include
transportation PRA, which has been done separately, separate
risk assessment for that.
We will need to select a site, and most likely, it
will be a generic site such as we've done for the AP600
reactor design, which should encompass as large as possible
that number of site characteristics in the country. We
don't include all of them, but a large percentage of the
various characteristics of the site.
The types of events that we will consider include
normal and accident conditions such as -- including design
basis and beyond design basis accidents; site-related
phenomena such as earthquakes, flooding, high winds as well
as man-made incidents that can occur during a handling of
the cask like cask drops or other handling accidents.
We also will look at the condition of the fuel in
the canister itself in the cask; whether there are some
preexisting fuel failures; the condition of the clad, which
will factor into the assessment in terms of consequences and
risk from radiological release from the fuel and from the
cask.
And a real important point that's part of the plan
is to say how are we going to assess the results? You know,
what is the criteria? We talked about that this morning and
developed -- and NMSS developing safety goals, whether it be
the probability of release of radioactive material to the
environment or radiation-induced latent cancer fatalities to
the public, and we expect to work very closely in NMSS to
provide input to specify these measures of success related
to the safety goals that you've heard discussed this
morning.
That's a broad picture of what the scope of the
program, the PRA, will entail. For some background; I think
this sketch will be useful just to see what we're talking
about.
DR. GARRICK: I may have missed something, Al.
DR. RUBIN: Okay.
DR. GARRICK: Are you calculating radiation-
induced latent cancer fatalities?
DR. RUBIN: If the release aspects include that,
we may be calculating that.
DR. GARRICK: Okay.
DR. RUBIN: Yes.
DR. GARRICK: All right.
DR. RUBIN: Depending on the release, and we may
get into the meteorology and --
DR. GARRICK: I see.
DR. RUBIN: Yes.
DR. GARRICK: So it depends on your source term.
DR. RUBIN: That's right.
DR. GARRICK: Yes; okay.
DR. RUBIN: Yes.
First, the fuel itself is put into this
multipurpose canister. The fuel assemblies are inserted in
that canister. It holds up to 25 BWR assemblies -- 24 PWR
assemblies or 64 -- 68 BWR assemblies. The canister is
drained of water and pressurized and filled with helium.
The purposes are to prevent corrosion of the steel on the
multipurpose canister itself as well as to enhance heat
transfer to the canister. When the canister is inserted,
the overpack itself --
DR. APOSTOLAKIS: Why is the called multipurpose?
DR. RUBIN: It's just the name given. It's
multipurpose because it can be used for storage as well as
transport.
The overpack is a large part of the structure.
That's approximately a 19-foot high structure, 11-foot
outside diameter. It's got an annulus of steel both inside
and outside that diameters, and it's filled with about 2.5
feet thick concrete, and the overall weight of this
structure when filled is about 180 tons.
In order to promote cooling in the long-term
during storage, there are inlet and outlet events, four of
them around the periphery of the multipurpose -- of the
overpack itself. So it's all natural circulation vented
system; no fans, no pumps, no active systems. It seems like
a relatively straightforward PRA kind of analysis compared
to a reactor. But it's -- even though it seems
straightforward, this is the first time that it's being
done.
And the first step in the program plan is to
identify the potential accident initiators, and that was
brought up this morning as an important point. We want to
be sure we have as complete as possible set. We've had
preliminary discussions with the spent fuel project office
staff to identify issues that they have thought about, and
we'll be adding some other issues, potential challenges to
the functions of the cask leading to a potential release.
And I'll get into some of these initiators in my next slide.
We'll assess the initiators that have been
identified in other related studies or PRAs and see if
they're applicable to the dark cask, and we'll include those
as appropriate. And it comes down to pretty much
categorizing the many initiators into their effect on the
mechanical impact of the cask; the thermal impact and impact
on criticality and perhaps some others, and for each of
those accident type initiators, we'll address the various
system modes, the handling, the onsite transport of the cask
and storage for the 20-year license of the cask itself.
To go through these preliminary initiating events
that we have looked at, I first want to make it very clear
that many of these events are included in design basis for
the dry cask, but we need to look for PRA purposes beyond
design basis types of events, and that's why we're including
the kinds of events that you see here. First of all, in the
categorization of mechanical impacts, we'll be looking at
handling accidents where the cask could be dropped either
before or after sealing of the canister, and I should have
mentioned -- let me go back for a moment -- the canister
itself.
The canister is sealed, and there is an overpack
seal for the whole dry cask system itself. So we will be
looking at potential weld failures of the seal on the
multipurpose canisters as an example of a failure or release
path. As an example for the drop of a cask, the current
design basis is the cask is designed for a drop height of 11
inches, right about a foot. So are there some ways or some
scenarios where, you know, that height by human error or
something else could be exceeded? And those are the kinds
of things we'll be looking at in the human reliability
analysis area.
In transferring the cask, that the cask
potentially could tip from sudden movements or stop during
onsite transport; in the storage of the cask, the long-term
storage, could the cask be hit by a tornado-generated
missile large enough to impact the cask, knocking it over or
impact by a truck or an aircraft accident? Could the cask
tip over from a seismic event? That's not mentioned on the
slide, but it is included in our list of events that we're
looking at.
[Pause.]
DR. HORNBARGER: So your tornado scenario is the
cask tipping over rather than being penetrated?
DR. RUBIN: Yes, yes; I imagine it would be hard
to penetrate a steel barrier with two and a half foot thick
concrete.
So these external events that we're looking at, by
the way, are very similar and parallel to that of a reactor
analysis in an internal, individual plant examination of
external events program, the IPEEE program.
DR. HORNBARGER: Of course, there are reports in
tornadoes of a piece of straw being driven through concrete
walls.
DR. RUBIN: And it would have to -- we have not
considered the straw impact on a concrete wall. We are
looking for some feedback during this discussion today.
Thermal air accidents is another area; obviously,
as I pointed out, the cask has a venting for heat removal.
Could there be some scenarios where the high heat load
assemblies are inadvertently loaded into the cask, having
higher heat loads that would be anticipated? In
transferring the cask onsite, looking at a fire from ignited
fuel from the transport truck.
DR. APOSTOLAKIS: I don't understand that. Can
you explain that scenario a little bit better?
DR. RUBIN: Which one? The transfer?
DR. APOSTOLAKIS: The transfer, yes.
DR. RUBIN: The cask is transferred by vehicle to
the storage pad, and if that vehicle has an accident, and
it's got a certain amount of fuel in it, what kind of
thermal loads from the truck --
DR. APOSTOLAKIS: Oh, the fuel.
DR. RUBIN: The truck, the fuel.
DR. APOSTOLAKIS: Oh.
DR. RUBIN: The gasoline --
DR. APOSTOLAKIS: Okay.
DR. RUBIN: -- in the truck, okay?
All right; and long-term storage, vent blockage,
perhaps, from flooding, long-term flooding, for example, how
long that could occur and what temperature conditions would
then result in the fuel in the assemblies, and what impact
would that have on the integrity of the fuel in the
canister? Look at high ambient temperatures associated with
a fire; looking at perhaps a fire associated with a crash of
an aircraft.
And then, finally, we're including criticality
events, where, from handling -- the possibility of highly-
enriched fuel being loaded in a cask or water ingression
from a flood with a failure of the overpack and a failure of
the multipurpose canister; flooding and causing criticality,
perhaps.
There's a fairly long list, and there are some
more details that I'm not going into today, but a real
important part is that we expect in our next step to do a
screening.
DR. APOSTOLAKIS: Your event trees will be fairly
simple.
DR. RUBIN: Oh, yes, oh, yes, and that's where
we're looking at four types of entries, many types -- you
know, there could be many possible ways that you could
impact the thermal loading by blocking the vents, anywhere
from flooding to a bird's nest that's not found for awhile,
but they basically are all in the same event trees; that's
right. We're boiling down a lot of these different types of
sequences into a short, limited number of event trees.
And a real important part in the first phase of
this program is the preliminary screening, the consequence
analysis. The purpose of this is to eliminate any
inconsequential either initiating events from further
consideration based on the sequence frequencies or the
release magnitude, and the release magnitude would be based
on the extent of cask failure, and the purpose of this
screening study also is to see whether we would need more
information for some additional, more detailed analysis.
And I'll get into this screening study a little more in the
next slide.
DR. GARRICK: Do you have a sense for which
scenario is going to be your bounding scenario?
DR. RUBIN: I mean, my gut feel is that, you know,
you have a passive cask sitting there that we really need to
focus on handling the human aspects of the transport. We
don't have a bounding scenario right now, but I think that
scenario where there has not been much done on the human
reliability of the cask handling, and we intend to look at
that pretty closely.
DR. GARRICK: Thank you.
DR. RUBIN: As far as the steps going for the
screening and preliminary consequence analysis, we are
identifying and -- the information available to come up with
the initiating events and the event trees and fault trees.
We'll assess the sequence frequency and the consequences on
a limited basis for screening purposes, and we would
eliminate any significant sequences from further
consideration. There are basically several ways to deal
with this.
MR. RUBIN: There is basically several ways to
deal with this, that a given initiating event, the cask
doesn't fail or the canister doesn't fail, and a third
screening approach would be, even if there were some kind of
mechanical failure, would the release have an adverse impact
on the public?
Clearly, there's data, there's methods going into
here.
We'll have some uncertainty and sensitivity
analysis that we'd expect would be part of this screening
study, and as we go along through this, particularly since
this is a first of a kind, we expect to have interactions
and peer review and comments as we go along, and it could be
that, once we're finished with the screening study, we may
have eliminated a lot of scenarios.
DR. KRESS: All of them?
MR. RUBIN: I can't tell you now. Stay tuned. If
I know that --
DR. KRESS: You're starting out with some sort of
a measure of what release would be acceptable to you?
MR. RUBIN: That's something that, as I mentioned
earlier, we're going to need to determine with NMSS what
measure of release. Do we use the same kind of measure
that's used for reactors? Given that there is nothing
better, we may try that, but I think that's yet to be
determined.
If there are some sequences or events that don't
screen, we would -- the next step would be a more detailed
frequency quantification for those sequences, fairly
straightforward looking, first to see what kind of data are
available, benefits of cost of getting that data, refining
the event trees and fault trees and computing sequence
frequencies and sensitivity studies as necessary.
The purposes for this more detailed analysis would
be to look at the radiological consequences, the
calculations for those important sequences that don't
screen, determine the releases from the cask, the off-site
consequences, as well as the risk calculations.
DR. APOSTOLAKIS: You will develop frequency
consequence curves?
MR. RUBIN: Yes. Come up with overall risk, yes.
DR. APOSTOLAKIS: What's DCS, by the way?
MR. RUBIN: Dry cask system.
DR. APOSTOLAKIS: Okay.
DR. KRESS: You're going to do this on a cask
basis or you're going to look at the whole --
DR. APOSTOLAKIS: The size of casks.
DR. KRESS: -- storage?
MR. RUBIN: We're looking at a site where there
may be on the orders of tens, fifty, at probably maximum 100
casks at a site.
DR. KRESS: They're all going to undergo the
accident at the same time.
MR. RUBIN: Well, not necessarily, no. We're
treating it individually, but if there is some -- a sequence
that would be a common mode failure, like a seismic event
tipping over casks, then it would impact more than one --
potentially could impact more than one cask.
DR. GARRICK: But if your screening indicates that
there is only one scenario that really can result in any
kind of a consequence problem, does that mean that's what
you'll analyze, or will you still analyze all the scenarios?
MR. RUBIN: No, if we can screen them out, we will
not continue, no. Our attempt is to get some results as
early as we can, you know, with some reasonable information,
and not do more than is necessary.
MR. HORN: What happens if they all screen out?
MR. RUBIN: I'd say, then, the next phase doesn't
-- we stop right there. We wouldn't have a need for more
detailed analysis.
But let me go on. You're leading into my next
slide, which is potential additional analyses or assessments
which may be a followon to this first pilot PRA, looking at
various fuel conditions such as high burn-up fuel, the
number of casks at a site, there's a proposal for a private
spent fuel storage facility in Utah, and looking at various
cask -- different designs. That's something that could
follow on to this.
We're looking at one specific design for this, the
Holtec High Storm. Other designs have different features,
and we want to be able -- maybe want to be able to see how
that could impact our screening analyses, for example.
The final slide is our schedule and the status.
Where we stand right now -- we've developed a
draft program plan in Research that we've discussed with
NMSS, and we're in the process of getting ready to send that
formally to NMSS.
The project scope, identifying the site
characteristics, the design, initiating events, we intend to
have done in the August timeframe, and we would hope that,
depending on the available resources and data, to have a
draft report available in about a year from now on the
screening assessment, and that depends on the availability
of data and what kind of information we need as we go along,
and then any followon, additional sequence calculations
would need to be determined following the conclusion of the
screening part of this project.
That hopefully will give you an overview of what
our plans are and where we're going.
DR. GARRICK: Are you finding anything unique here
with respect to methodology requirements? In other words,
are at a loss for methods for any part of the analysis?
MR. RUBIN: I think what we're focusing on -- we
want to have a complete set of the sequences. I'd say no, I
don't think we've met that through the problem, the area,
but we want to include the sequences and the data. If
there's not data, what are we going to do?
DR. GARRICK: Yeah.
MR. RUBIN: Are we going to do some analyses?
We're going to base our assumption on some extrapolation of
analyses that have already been done for design basis-type
events? That's what I see as probably the most resource-
intensive, as well as the human reliability aspects.
DR. KRESS: I think you'll be faced with some of
the same issues pointed out with the spent fuel pool study,
what's the source term, how you deal with the fire-driven
event, and what are the things you don't know about and the
effects of hydrided clad.
I think the issues are the same for the cask, plus
a few more, and that's what do you know about long-term
deterioration of the cask that may cause internal corrosion
events like -- driven by moisture and maybe hydrogen that
gets produced in the process.
MR. RUBIN: I should mention at this time, in
response to that, there are some ongoing related activities
that Research has in support of NMSS and dry cask.
Now, the results of those programs -- probably
most of them will not be available in time for the screening
study, but for example, the -- looking at -- I think it's
the Surry cask, fuel in the Surry cask, looking at the
condition of that fuel, they took an initial, the fuel
cladding looks fairly good, but they haven't done analyses
in the fuel cell yet.
DR. KRESS: The problem with the screen that I see
is how do you determine the initiating frequency of a fire
that's a self-igniting fire?
MR. RUBIN: A self-igniting fire is okay.
DR. KRESS: You know, I see how you can get more
of a fuel spill from a truck. You could probably come up
with the frequency of that, but a self-ignited fire that may
be driven by the -- by a change in the heat transfer
properties of the system so that it overheats to some
emission temperature that's driven by the hydrided state of
the fuel -- you know, how do you get a frequency?
MR. RUBIN: Well, you have an inert atmosphere.
You have helium. It's a helium-filled canister.
So, you would have to have a sequence where the
helium has escaped, you haven't detected it for a long time,
and there are inspections that go on on storage to look for
those kinds of things, to look to see if the vents are
blocked or not.
DR. KRESS: It may be driven by the fact that you
have that helium.
MR. RUBIN: Oh, yes. Oh, yeah.
DR. KRESS: Could very well be.
MR. HORN: Just for my education, you mentioned
that the cask drop was 11 inches, but the multi-purpose
canister is tested at a higher elevation, is it not?
MR. RUBIN: Oh, yes, it is. That's about three or
four feet. The transfer cask --
MR. HORN: Yeah.
MR. RUBIN: Its drop rate is about, I think, 40-
some-odd inches. When I said the 11 inches, that was for
the whole over-pack.
MR. HORN: There's also a design basis fire test?
MR. RUBIN: Yes, there is, and it's the amount of
fuel that's in the truck, and the question is if there's
more than that -- those kinds of things are in the design
basis, which we already -- you know, that information has
been provided, at least the results of those analyses have
been provided to the agency.
DR. GARRICK: As long as it's not located next to
the fuel tanks for the diesel generators, huh?
MR. RUBIN: A lot of what-if's.
DR. GARRICK: All right.
Any other questions?
[No response.]
DR. GARRICK: We'll enjoy hearing a progress
report as you start.
MR. RUBIN: Okay. We intend to keep the joint
subcommittee informed.
DR. GARRICK: Okay.
DR. KRESS: Given the status and progress of Yucca
Mountain, I think this is an important study, because we're
probably going to have a lot of dry cask storage on-site.
MR. RUBIN: And if we need to go into the -- you
know, the more detailed sequence analysis, that's going to
take an extended -- probably an extended period of time.
DR. GARRICK: Thank you. Thank you very much.
MR. RUBIN: You're welcome.
DR. GARRICK: It's a remarkable event, but we're
on schedule.
DR. KRESS: You run a lot tighter meeting than
George does.
DR. GARRICK: George has a lot more patience than
I have.
Okay.
Why don't we adjourn for lunch, then, unless --
and we're going to reconvene here and discuss protocol as
soon as we grab a sandwich and bring it back here, 12:15.
[Whereupon, at 11:55 a.m., the meeting was
recessed, to reconvene at 1:00 p.m., this same day.]
. A F T E R N O O N S E S S I O N
[1:00 p.m.]
DR. GARRICK: The meeting will come to order, and
this afternoon we're going to talk about risk-informing fuel
cycle programs, etcetera, etcetera, and Mr. Sherr is going
to take the lead on it, I gather.
MR. SHERR: I'm going to give a quick overview on
the background of the fuel cycle programs for risk-informing
the regulations, and Dennis Damon, who is now with the NMSS
work group but until recently has been in FCSS and been an
integral part of the work that we've been doing in this
area, will be providing more detailed information.
DR. APOSTOLAKIS: Now, what is the definition --
in the documents I have, there was a very long paragraph
where one can find the definition of byproduct material, but
the definition itself was not given.
DR. GARRICK: It's in the Atomic Energy Act.
DR. APOSTOLAKIS: I have to go back to that. It
gave me all the paragraphs, but special nuclear materials
are uranium and plutonium?
MR. SHERR: Enriched uranium.
DR. APOSTOLAKIS: Enriched uranium and plutonium.
MR. SHERR: Right.
DR. APOSTOLAKIS: Okay.
MR. SHERR: And other materials as the Commission
may determine, which they haven't determined any so far,
since 1954.
The major activity that's going on in terms of
risk-informing activities in the fuel cycle area -- and I
guess maybe it's worthwhile to just step back a second, when
we say fuel cycle area, what we mean.
The regulations and their development would apply
to essentially the existing fuel cycle fuel fabrication
facilities. They will also apply to the plutonium mixed
oxide facility that's currently planned, and we expect to be
receiving a license application before too long. So, those
are the facilities that are immediately expected to be
subject to this regulation.
This rulemaking has been going on for quite a long
time. It was initiated at the Commission's request in 1993,
and we are nearing the final stages. The final rule package
is due to the Commission within the next couple of weeks,
May 15th.
In fact, when I leave here, I'm going to go back
and try to get the package out of the office.
In parallel with this effort is an effort that's
directed to revising the oversight program, similar to what
has been done in NRR for the reactor area, and this program
is also directed to make a more risk-informed perspective in
terms of the inspection program.
First slide.
There's two events that occurred that affect the -
- significantly the current rulemaking.
One was in 1986, the Sequoyah Fuels accident, and
that didn't directly affect this rulemaking other than the
fact that it raised the issue in terms of is NRC responsible
for chemical safety as well as radiological safety, and
there was a lot of discussion about this, congressional
hearings, and the result of all that was a memorandum of
understanding between the Nuclear Regulatory Commission and
OSHA which limited NRC's responsibilities in terms of
responsibility for chemical consequences and protecting
against them but, at the same time, identified certain
responsibilities.
This rulemaking addresses those responsibilities,
and later on, when Dennis is talking about the performance
requirements of the rule, you'll see how it does that.
DR. GARRICK: It should be pointed out, of course,
that this UF-6 release fatality was not a radiation
fatality.
MR. SHERR: No, that's right, and that was the
controversy at the time, which agency should have done
something about this type thing, and there was a lot of
different views on that and a lot of pointing different
directions.
In 1991, there was a near criticality incident at
one of the fuel fabrication facilities, and following that,
there was a significant review that was conducted, and a lot
of problems were identified with the way safety programs
were being implemented at facilities.
It wasn't that they were inadequate, but one
didn't have the confidence that they were always going to be
maintained.
Basically, the fuel cycle licensing approach was
done on a renewal-to-renewal basis, and whatever changes
happened to the safety program between renewals was outside
the oversight of NRC, and how well there was control in
between time varied depending on the specific circumstances,
and the particular situation at the facility where they had
the near criticality incident, there was a case where
controls were changed, and so, there was a clear need for
better configuration management.
As I said, in 1993, the Commission -- after a few
other things were done, the Commission said it's time to
pursue a rulemaking at essentially -- they didn't use these
terms in those days but essentially with a focus on the
conduct of an integrated safety analysis which had as part
of that -- as I say, they didn't use this terminology, but
risk-informed, performance-based rule.
DR. APOSTOLAKIS: Now, at that time, I guess, the
terminology was different, too, because today we would not
say increased confidence in margin of safety, we would
simply want some risk acceptance criteria, wouldn't we, Tom?
That's really what it means. If you are quantifying risk,
you want some risk goals.
MR. SHERR: Yeah.
DR. APOSTOLAKIS: Yeah.
MR. SHERR: Yeah. And that's exactly what the
rule does, and that will be a significant part of the
presentation as you -- if you've looked ahead in any of the
view-graphs, we'll be discussing those risk goals.
But the integrated safety analysis is essentially
a systematic review of the hazards and a means for
identifying controls.
I brought with me the definition. I'm not sure
it's in any of the material that you have, and it's defined
in the proposed rule as a systematic analysis to identify
facility and external hazards and their potential for
initiating accident sequences, the potential accident
sequences, their likelihood and consequences, and the items
relied on for safety.
So, basically, it's a systematic safety analysis
where it simultaneously considers the radiological nuclear
criticality, fire, and chemical safety hazards.
DR. GARRICK: What is that you're defining?
MR. SHERR: Integrated safety analysis. That's a
inherent part of the whole rule and the focus.
From the -- just to give a little -- I'm not sure
how familiar you are with the fuel cycle industry as
compared to the reactor part of the industry, but it's
worthwhile to note two significant differences between the
fuel cycle and the reactor area.
One is that the fuel cycle facilities have diverse
processes. The equipment varies from facility to facility.
It's not where, if you've gone to one reactor of one type,
it's pretty much the same as the next one in terms of
general equivalence-type thing.
The other thing is that it's a less contained
environment.
There are a lot more administrative actions and,
accordingly, administrative controls that are involved as
compared to engineering controls, and these things affect
both the database that might be available in terms of
equipment reliability, as well as the ability to quantify
the effectiveness of controls, the administrative controls.
Next slide, please.
In terms of the major elements of the rule, as we
mentioned, the focal point of the rule is the requirement
for licensees to conduct an integrated safety analysis,
which we referred to as ISA.
As I mentioned, the integrated safety analysis
essentially identifies the accident sequences of concern,
and for each one of those accident sequences, identifies the
items relied on for safety that will either prevent that
accident from happening or to sufficiently mitigate its
consequences so it is reduced in terms of the level of
concern.
DR. APOSTOLAKIS: So, how is the ISA different
from a PRA?
MR. SHERR: Well, I think, in overall concept,
it's the same, and in fact, PRA -- a PRA is one example of a
methodology that could be used, and using event trees is
certainly what we would expect for complex processes, and I
think the biggest difference -- and this will be an issue
that Dennis will be talking about later -- has to do with
the degree of quantification that we expect from the
process.
DR. APOSTOLAKIS: In order to avoid the
proliferation of terms, why can't we just call it, then, a
PRA and then define different types of scope where in some
instances perhaps you don't want to go into detailed
quantification and in others you do?
I mean we already have level one, two, and three
for reactors which are PRAs of different scope. One stops
at the core damage event, the other proceeds to containment,
and the third one is, you know, the full PRA with risk
estimates.
MR. SHERR: Yeah.
DR. APOSTOLAKIS: I think it would be important to
harmonize terminology, don't you think?
MR. SHERR: Well, this terminology has been used
in the fuel cycle area now for quite a number of years. A
number of licensees already have license conditions to be
conducting ISAs.
They're not geared to any particular performance
standards that the rule would establish, but that's an open
question, I guess.
DR. GARRICK: What you're really saying is that
the ISA can be -- can embrace either a deterministic
approach or a probabilistic approach. Is that right?
MR. SHERR: Well, it can use quantifiable ways of
assessing likelihood or less quantifiable ways of assessing
likelihood, and as I was saying, Dennis is going to be
addressing that particular aspect, and I think that's the
major difficulty in dealing with the fuel cycle facilities,
is that it's much more difficult to do a quantified safety
analysis.
DR. APOSTOLAKIS: But then if you don't do that,
how can you demonstrate that you have increased confidence
in the margin of safety? What metric would you use for the
margin of safety, or will it be qualitative and say, gee, I
have an extra barrier, so I have increased confidence? Is
that really what it is?
MR. SHERR: Dennis?
We're skipping into the more detailed part of the
presentation.
MR. DAMON: Well, my own impression about the
increased margin of confidence and safety is not really the
assessment of risk.
It is the fact that the knowledge both of the
plant staff and of the NRC staff as to what actually you
have in the way of a safety design was not very complete,
not well documented, not analyzed systematically.
Consequently, if you ask somebody the question,
what is the risk of this facility, they say, well, I think
it's okay, but I'm not very confident.
It's the second order of uncertainty. The word
"uncertainty" has been mentioned many times here. It's the
uncertainty level that was high.
DR. GARRICK: It sounds like what you're
attempting to do here is to provide more flexibility in the
rule than you think would be provided if you used the words
"PRA."
MR. SHERR: That's true.
MR. DAMON: Right. Because the rule, as you will
see, is mandating things. It's not like PRA has been used
elsewhere as a form of information for guidance. It's a
requirement that they do certain things.
DR. GARRICK: Clearly, a PRA would be an
acceptable ISA.
MR. DAMON: Yes.
MR. SHERR: Clearly.
DR. GARRICK: I'm with George. I don't quite
understand why we went in that direction, but I'm not sure
wed can do much about that at this point, and I am
sympathetic a little bit, because this evolved with time,
before probabilistic analyses was really a part of the
process.
DR. APOSTOLAKIS: That reminds of the individual
plant examination situation, where, when the generic letter
was published in 1988, they deliberately avoided the word
"PRA," because some people were arguing that you could do
this, you could identify the vulnerabilities using other
ways, other methodologies.
Now, six, seven years later, we got all the IPEs,
and there wasn't a single one that did not use PRA. So, the
reality of it was that, really, the generic letter asked for
a PRA, at least a level one PRA.
Is that correct, Tom?
DR. KRESS: Yes.
DR. APOSTOLAKIS: Your impression, too?
So, why perpetuate these things?
There is some fear, I guess, when it comes to PRA,
that people will have to produce an 11-volume document with
all the details in reactors.
I mean if you don't have a system that has the
highly redundant and diverse systems of a nuclear power
plant, your PRA will be much simpler, but it will be a PRA.
I mean the reason why those event trees go around
the room is that, in reactors, you have all these, you know,
redundancies and opportunities for operators to intervene
and do things and so on.
If you didn't have those, then maybe one page
would be enough.
But it's a matter of scope.
You know, I appreciate the fact that, you know,
these words have been used already in the regulations, but
at some point we have to start creating some harmony.
DR. GARRICK: What I guess you're telling us is
that integrated safety analysis is more of a process than a
prescriptive analytical activity.
You don't -- we'd get real concerned if it was so
prescriptive that it was something very different from a PRA
or precluded a PRA being an acceptable form or an acceptable
interpretation of an integrated safety analysis, but it
sounds like you've accommodated that.
DR. APOSTOLAKIS: In some instances, the way I
understand it, the ISA would allow you not to calculate the
consequences, just scenarios, and in other instances, it
would not even ask you to produce probabilities, but in
other words, you take the complete triplet, and instead of
subtracting things, for some reason, which remains to be
determined --
DR. GARRICK: That's why they call it safety and
not risk.
DR. APOSTOLAKIS: Yeah. But the idea is there.
It's the same thing, really.
DR. GARRICK: Yeah.
MR. DAMON: Part of the reason why there's a
difference in terminology is historical, the methodology of
all -- not from NRC groups but from the chemical industry.
DR. GARRICK: Right. We understand that.
DR. APOSTOLAKIS: But even when they borrowed our
PRA, they called it QRA.
MR. HORN: Maybe we could introduce that.
DR. APOSTOLAKIS: Yeah.
MR. SHERR: The ISA guidance document that has
been developed weighs heavily on the chemical industry
guidance document for hazards analysis, which, as you say,
includes a broad spectrum of specific approaches.
DR. APOSTOLAKIS: But again, you know, let's not
be in awe of that. The truth of the matter is we're ahead
of them when it comes to safety issues. I mean that's the
truth. We are actually quantifying risk.
So, the fact that the chemical industry is doing
that doesn't mean anything to me.
DR. GARRICK: I think we ought to hear out their
story, and I have some of the same anxieties, but I believe
history has put us where we are, and to try to undo it would
be quite difficult.
DR. APOSTOLAKIS: I appreciate your position. I'm
just saying that maybe it's time we started thinking --
DR. GARRICK: I'd feel much better if, everywhere
I see ISA, I can put PRA.
DR. APOSTOLAKIS: Yeah, as long as we understand
that the scope may be different depending on the situation.
DR. GARRICK: Because it's not risk-informed if we
don't deal with the triplet, as George says.
DR. APOSTOLAKIS: That's right.
DR. GARRICK: Okay.
MR. SHERR: So, the ISA identifies the basic
controls that are either going to prevent or mitigate --
prevent the accidents or mitigate their consequences, and in
addition, the rule requires the facilities to maintain
management measures that ensure that the items relied on for
safety are, in fact -- will be, in fact, available and
reliable, and essentially, the bottom line of the rule says
that the results of your ISAs has to demonstrate that the
performance to the requirements of the rule be satisfied.
DR. APOSTOLAKIS: So, let's see now what that
means. Are you going to talk about it later?
MR. SHERR: Yes.
DR. APOSTOLAKIS: Okay.
MR. SHERR: Very shortly.
DR. APOSTOLAKIS: It's too prescriptive.
DR. GARRICK: Well, one of the things I notice in
the material that we were supplied, which was the rule,
etcetera, it says that -- and maybe we don't need to go
through all of this -- there are four major steps in
performing an ISA, and to deal with one of the questions
that George raised, step number three says determine the
consequences of each accident that has been identified for
an accident with consequences at a high or intermediate
level, as defined in the regulation, the likelihood of such
an accident must be shown to be commensurate with the
consequences as required in 10 CFR 70.61.
So, you've got it all mixed in here, which even
makes more for the case of why ISA, why not just PRA, but
anyway, I think we understand where you're going.
MR. SHERR: Well, I think the important thing is -
- I mean without regard to what we've called the terminology
-- is that the performance requirements are in terms of
risk. They're saying the risk needs to be limited, and as
Dennis will be going into more detail, we've identified two
categories, high consequence and intermediate consequence
events, and essentially the requirements for high
consequence events -- they have to be highly unlikely, and
intermediate consequence is unlikely, and those terms are
not defined in the regulation, they're discussed in the SRP,
and again, that's part of the detail.
DR. KRESS: What do you do with the consequence
events that are in between those two?
MR. SHERR: That are below those?
DR. KRESS: Fifty rems.
MR. SHERR: They're mutually exclusive.
DR. KRESS: Oh, I see.
MR. SHERR: But it's just a question of what's
below those levels, and that's treated as part of Part 20
requirements.
Part 20 still comes into play. This is only
dealing with the accident.
DR. APOSTOLAKIS: What's the limit for workers at
reactors? Is it 100 rem? It's 25, isn't it? Five rem.
So, why is this 100?
Let's go back to the --
MR. SHERR: Actually, Dennis skipped ahead here.
DR. APOSTOLAKIS: Yeah. Dennis doesn't know us
very well.
Okay.
So, for workers, it's 100 rem or more. I don't
understand that. Must be highly unlikely.
MR. DAMON: These are accident risks. I mean the
5 rem is an occupational dose.
DR. APOSTOLAKIS: Oh, so, this is accident.
MR. DAMON: These are accidents.
DR. APOSTOLAKIS: So, you are requiring, then,
accidents that lead to this dose to be highly unlikely.
Okay.
DR. KRESS: Now, suppose I have an accident that's
projected to cause 1,000 rems. Is my definition of highly
unlikely the same as for 100 rems?
MR. SHERR: Theoretically, yes.
DR. KRESS: That seems a little strange to me.
DR. GARRICK: It's highly, highly unlikely.
DR. KRESS: I would want some gradation in that.
MR. DAMON: That's a good question which I don't
think could be answered outside of a court of law.
What I did in the Standard Review Plan when it
came to that exact point is I said, because that upper
category is open-ended on the upper sign, that whatever
guideline -- the guidelines that were developed in the
Standard Review Plan as to how to judge whether something is
highly unlikely or not were addressed to the typical type of
accident that would occur in that group, but it made a
warning statement that if your accident is substantially
above or below this typical case, then the likelihood has to
be scaled accordingly.
DR. KRESS: So, you did deal with that as
qualitative.
MR. DAMON: Yes.
So, I'm claiming, as a member of the staff, that I
can interpret that in a flexible way.
Now, whether that would stand up, you know, I
don't know.
DR. KRESS: That looks like a bit of a problem to
me.
MR. DAMON: It was considered early on as to
whether to put additional categories, but then you get into
the thing and you'd end up having some kind of complementary
cumulative distribution in the rule or something.
DR. KRESS: Well, I'm not so sure that's a bad
idea. You know, that might be a good way to cover the whole
spectrum.
DR. APOSTOLAKIS: So, what's the third category?
Is there a category -- we have highly unlikely, unlikely,
and expected?
MR. DAMON: What Ted was saying is, if you look at
the criteria for unlikely, you could be below that. You
could have an accident that produced effects below that, and
that accident is not addressed by the requirement that's
stated here, it's just left, and that's actually a risk-
informed aspect of this.
There was a deliberate decision that accidents at
that level weren't worth the effort to impose a requirement
to analyze.
DR. APOSTOLAKIS: What is the dose limit for
routine activities? Is that five? For workers. Okay.
MR. DAMON: So, there is a window there.
MR. MARKLEY: George, this is that special planned
exposure category that I was telling you about this morning,
25 rem or better.
MR. SHERR: The last overview point was just the
fact that, when this rule goes into effect, the completion
of the integrated safety analyses and implementation of the
controls at the facilities to satisfy the performance
requirements will need to be implemented within four years
of the rule is published, which we're hoping will be late
this summer.
And with that, I'm going to let Dennis then go
into the more detailed parts of the performance
requirements.
MR. DAMON: My name is Dennis Damon. As Ted
mentioned, I, up until recently, worked for him in this area
and other areas, and now I'm in the NMSS risk group,
addressing risk-informed regulation.
DR. GARRICK: We've heard of that.
MR. DAMON: Again, the purpose of this -- doing an
ISA is not the same as a risk assessment. It is a
regulatory mechanism, as opposed to an attempt to assess
what the risk is.
It's an attempt to induce the licensees to do
systematic safety analysis, identify what they're relying on
for safety, and make a determination that it's adequate, and
it's based on the OSHA process hazard analysis concept
that's been implemented in their domain and for which they
have about 100,000 licensees which they require do this type
of analysis, and it's mostly qualitative.
Occasionally, people will do what is a PRA, and
these -- so, the attempt to bring a risk structure into this
ISA is to specifically ask that consequences and likelihood
be addressed separately and in the manner that it's
described here, and that is to ask that all the accidents
identified in the ISA -- that the consequences be calculated
and determine whether they are -- in which one of these
categories they are, below unlikely, unlikely or -- these
are also referred to as intermediate consequence and high
consequence.
So, the accidents that are identified are going to
be determined to be in one of these categories by
quantitative calculation, but then, likelihood -- we do not
expect the current licensees to, in general, quantify
likelihood when they take the next step, which is to
determine whether it's highly unlikely or not.
DR. APOSTOLAKIS: You do not expect them to
quantify it.
MR. DAMON: We do not.
One of the reasons the word "PRA" wasn't used -- I
mean it's used in the Standard Review Plan. There's a
statement in there that it is one acceptable way of doing
things, of meeting the rule, but the licensees vigorously
resisted.
DR. APOSTOLAKIS: Do you think that people will
have a common understanding of what a highly unlikely
sequence is?
MR. DAMON: No, and that's why, in the Standard
Review Plan, I attempted to provide some guidance to our
staff reviewers and, indirectly, to the industry as to what
we believe.
DR. APOSTOLAKIS: I don't remember that. Can you
give me some idea of where that guidance is?
MR. DAMON: The Standard Review Plan is -- it's
not here.
Along with the rule, there's a Standard Review
Plan for reviewing the license application or an ISA summary
when it comes in, and in there, there's a chapter on ISA.
Chapter three is on ISA.
In that chapter, it will have -- it has acceptance
criteria for likelihood.
In other words, there will be a likelihood
evaluation done by the licensees as a required element of
the ISA.
So, they will submit what they think highly
unlikely means, and in the Standard Review Plan chapter, it
says what we think it means.
DR. APOSTOLAKIS: So, is there a place where it
says clearly highly unlikely is this?
MR. DAMON: If you look --
DR. APOSTOLAKIS: Yeah.
MR. DAMON: -- in the slides --
DR. APOSTOLAKIS: Oh, yeah, you are quantitative,
on 3.0-28. Highly unlikely, a frequency of less than 10 to
the minus 5 per accident per year. So, with tears in your
eyes, you're back to PRA.
MR. DAMON: Yes. Yes, that's right.
DR. APOSTOLAKIS: And then unlikely is a frequency
of less than 10 to the minus 2 but more frequent than 10 to
the minus 5 and not unlikely -- I guess that's likely -- is
more frequent than 10 to the minus 2. So, you are becoming
quantitative.
MR. DAMON: Yes, right. There's quantitative
guidance in there, and in fact, in the section -- the more
recent version of the Standard Review Plan is slightly
different than what's there, because it was recognized that
the number of accident sequences that are identified in
these ISAs is under the control of the analyst, he can
partition his trees more finely or more coarsely, and so, to
preclude playing games with what's the frequency per
accident sequence, which is the way the rule is stated --
the rule is explicitly stated, it's each event must be
highly unlikely, and so, to preclude that game-playing, the
guidance says that you divide by the total number of
accidents in the entire industry to figure out what's an
acceptable number.
DR. APOSTOLAKIS: Divide by the total number of
accidents?
MR. DAMON: You can imagine all the different ways
you could do this, and I thought of them, and there's no
easy solution to the situation of proposing a risk goal
unless you do it cumulatively, and then you have to be
quantitative.
DR. GARRICK: It seems that we are kind of playing
games here.
It seems, by the time you do a good job of
answering the questions that you're asking in the rule, you
have built the basis for a risk curve.
DR. APOSTOLAKIS: That's correct.
DR. GARRICK: You have your CCDF. All you need to
do now is decide what the uncertainties are.
But it's kind of strange that we're in this
situation where we have to dance around PRA so much because
of the stigma associated with it, or for some other reason,
and call it other things.
There's no way you're going to be able to
convincingly analyze a chemical plant and answer these
questions without essentially having the critical points on
a CCDF, is there?
MR. DAMON: Well, I tend to agree that, in many
cases, you will look at a case that's being analyzed and you
won't be able to decide, you know, whether it's highly
unlikely or unlikely without doing something quantitative,
but --
DR. GARRICK: I also get very nervous when we
start talking about separating consequences from likelihood.
Most times when we do that, we get in trouble,
because we get consequences out there which people pick up
as if they're not unlikely, and the one advantage of a risk
form for the results is that you can't do that. The risk is
-- combines the two and forces consideration of them in
combination.
But anyway, we're a bit late in our commentary on
this.
But it does have some underlying problems that
indicate that there's still a long ways to go in the whole
arena of risk communications before we can make the
transition that is a clear algorithm for becoming risk-
informed.
MR. DAMON: They do, in fact, use PRA on fuel
cycle facilities in Europe.
DR. GARRICK: I know.
DR. APOSTOLAKIS: Where?
DR. GARRICK: In Europe.
DR. APOSTOLAKIS: No, even here. I was reviewing
some PRAs that were done for DOE 10 or 15 years.
DR. GARRICK: Yeah, DOE did a PRA on the ICPP, the
chemical reprocessing plant.
DR. APOSTOLAKIS: It was a PRA.
DR. GARRICK: Yes, it was a bona fide PRA.
DR. APOSTOLAKIS: John, you said we are late.
What stage is this at now?
You're sending it up when?
MR. SHERR: We've gone through the proposed rule
process, and the rule is due to the Commission May 15th.
The final rulemaking package is due to the Commission May
15th.
DR. APOSTOLAKIS: You've been through the public
comment period and everything?
MR. SHERR: Yes.
DR. APOSTOLAKIS: Wow. Why are we involved so
late? We don't exist before. Did the ACNW have a chance to
review it?
DR. GARRICK: No.
DR. APOSTOLAKIS: No?
MR. HORN: I suppose we all had a chance to review
it if it was out for public comment, but we didn't do it.
DR. APOSTOLAKIS: Well, that's something for us to
discuss.
DR. GARRICK: Yes, I think so.
Carry on.
MR. DAMON: This is one point that should be made.
The jurisdiction of the NRC is restricted to certain things.
Not all chemical accidents are within our jurisdiction to
address in this rule, so it's only certain things.
The ISA -- the rule defines this term, "item
relied on for safety," and it's important to recognize why
the different terminology was chosen. It's because most of
the things relied on for safety in these plants are
procedural. They're what we call administrative controls.
There is hardware involved, but it's usually hardware
operated by somebody.
DR. GARRICK: But Dennis, is the NRC worried about
anything other than radiation risk?
MR. DAMON: Yes, chemical death or health effects
due to chemicals.
DR. GARRICK: I know they are, but I mean really.
The foundation of the regulations --
MR. DAMON: In these plants, yes. Like Ted was
saying, the only person that's been killed in an NRC plant
regulated in the fuels materials area was a chemical death.
DR. GARRICK: Yes.
MR. DAMON: And so, we are concerned about it for
that reason.
There are many different things that could go
wrong and kill somebody in the plant.
MR. MARKLEY: Even the radioactive materials are
more chemically toxic than they are radioactively in a lot
of cases.
MR. DAMON: So, it is a real concern. We've hired
chemical engineers and chemists and we're seriously
concerned about chemical safety in these plants for the
things within our jurisdiction.
Of course, the other radiological hazard is having
a criticality event, which is -- you know, in light of
Tokai-Mura, that's a real thing, too.
DR. APOSTOLAKIS: Do these ISAs exist now? Have
they done them?
MR. DAMON: Yes. There six, seven fuel cycle
facilities.
DR. APOSTOLAKIS: They have done these ISAs?
MR. DAMON: What happened was the staff attempted
to get -- when it was determined that they wanted the
licensees to do them the staff tried to get the licensees to
do it without a rule, and some agreed to do them and some
point blank refused. So, some have done them.
Only one of them has really done it to near
completion, and that's BWXT, which is a naval fuel
fabricator.
DR. APOSTOLAKIS: And that will be submitted to
you or has been submitted?
MR. DAMON: It has been submitted, but it's been
disguised.
It was submitted as what's called a Chapter 15 of
their license application, which is a description of their
plan, but it actually is a summary of their ISA.
DR. APOSTOLAKIS: I wonder whether a way around
the problem we're facing here is to recommend to the
Commission to issue a -- can they issue generic letters in
this area and ask for identification of vulnerabilities and
let the industry then discover by itself that they really
need a PRA?
MR. MARKLEY: That's what they did with 88-20,
George.
DR. APOSTOLAKIS: For reactors.
MR. MARKLEY: Yeah.
DR. APOSTOLAKIS: So, what I'm saying is would it
make sense to recommend something like this here, because
unless you do it, you will never be convinced that you need
a PRA.
So, you will ask them to identify vulnerabilities
and let them do it any way they like, and eventually they
will all do a mini-PRA.
Then we will not try to derail this.
DR. GARRICK: Just as a matter of curiosity, do we
have a sense of the scope of the six or seven ISAs? Are
these --
MR. DAMON: Yes. I mean I'm familiar with how
much they've done.
DR. GARRICK: Are these 10 man-year studies or one
man-year studies or what are they?
MR. DAMON: I would say that the BWXT one is
easily up in the 10 man-year category, and most of the rest
of them will be approaching that.
DR. APOSTOLAKIS: Is it because they are doing it
for the first time?
MR. DAMON: I think it's a couple reasons.
One of them is the number of processes for which
you have to do analysis.
Instead of a single machine, you know, reactor
that's basically a fairly simple machine, they have -- like
a typical plant might have 100 different processes, and each
one of them is a unique piece of machinery that has its own
design and own safety design.
So, just the sheer number of things they have to
analyze is one factor.
The other one is that they -- you have to do it
with a team -- a chemical expert, a criticality expert, a
PRA-type expert.
By the time you're done, you've got four or five
people sitting there working on this simultaneously. So, it
tends to be expensive.
DR. APOSTOLAKIS: I wonder whether this
subcommittee should actually spend a day on these things.
DR. GARRICK: Well, what I was thinking, George,
before we go too far on this, it might be very constructive
for us to get a presentation on one or two of these ISAs --
DR. APOSTOLAKIS: That's what I mean.
DR. GARRICK: -- a specific presentation of an ISA
and to get a more in-depth sense of just the nature of the
analysis and the depth of the analysis. That's something we
may want to talk about.
DR. APOSTOLAKIS: Yeah.
MR. DAMON: I thought about that before I came
here. I thought about bringing slides that showed some of
the -- extracted from some the existing ones, but they're
all -- they're classified as proprietary information, so
we'd have to address that somehow.
DR. GARRICK: Yeah.
DR. APOSTOLAKIS: Won't be the first time.
DR. GARRICK: Yeah. Right.
MR. DAMON: Yeah, I agree.
DR. GARRICK: What about the naval facility?
MR. DAMON: It's quite easy to find stuff that's
not classified. It's just they'd have to pick ones that
didn't have anything that they didn't want their competitors
to know about, maybe.
DR. GARRICK: Right. Well, I happen to know that
a few pieces of the Sequoyah Fuels facility was analyzed on
a probabilistic basis. So, there's pieces and parts of
probabilistic fuel cycle analysis around.
MR. DAMON: Right. For example, the NFS facility
in Irwin, Tennessee, a few years ago -- they wanted a
license amendment to have a process for down-blending
highly-enriched uranium down to reactor levels of
enrichment, and that's a hazardous operation, because
normally the way you assure safety is to make the geometry
of the piping and vessels small enough so that the high-
enriched won't go critical.
Well, they wanted to do it in a way where
eventually they're going to get to a geometry that would be
critical if they were high-enriched.
So, it was such a touchy thing -- they did a
quantitative PRA of that process design, but see, a lot of
these processes, the safety design is so incredibly simple
that even calling it an analysis is hard to do.
For example, like at BWXT, they fabricate metal
reactor cores for submarines, and the fabrication processes
are working with a big machine shop, they work with big
pieces of metal, and the typical way they assure criticality
safety is simply to have a rack that holds only so many
piece parts at a certain spacing, and that's what they work
out of.
They take the piece out of the rack, they work
with it, they put it back in the rack, and the rack is -- it
would probably take, you know, 10 times that much or six
times as much as in the rack to be capable of being critical
if you took it out of the rack and assembled it into a form.
So, it's just a sheer safety margin and the way
they work with things that they control criticality. As
long as people that are working there follow the rules, they
are very, very far from criticality, and so, you can see
it's a lot of human reliability, is what it is.
DR. GARRICK: I think one of the things that would
make a lot of us feel a lot better -- and I've read this to
some extent but not in great detail, because it's awfully
thick -- I'm talking about the rule -- is that if there was
more made of the fact that a PRA is an acceptable and
established approach for carrying out the integrated safety
analyses, the fact that that was totally, from what I read,
excluded, I think, is a missed opportunity.
MR. DAMON: Well, it certainly -- in the Standard
Review Plan, it's quite clear that it's not only an
acceptable way, it's -- in the area of identifying
accidents, there are statements made that, for a complex
process, fault trees should be used.
I mean our experience in reviewing the parts of
ISAs that have been submitted is that some of the licensees
attempt to analyze a system that clearly calls for fault
tree by a more simplistic technique that is too vague and
does not really explain what accidents can occur in the
process, and so, we have made it -- tried to make it clear
in the guidance that that's what's called for, and in fact,
NUREG 1513, which is the ISA guidance document -- it has a
flow chart in for selecting methodologies that would drive
one to choose a fault tree for an appropriate complex
process.
DR. APOSTOLAKIS: Do we have this NUREG?
MR. SHERR: It's part of the proposed rule
package.
DR. GARRICK: The guidance document.
MR. DAMON: ISA guidance.
DR. APOSTOLAKIS: The NUREG is here?
MR. SORENSON: It's in that package I sent you.
MR. DAMON: So, there's two guidance documents.
Actually, there's three, which I was going to get to.
There's the ISA guidance document, which primarily
addresses the overall architecture of an ISA and how you --
and all the different methods for identifying accidents,
like fault trees, event trees, what-if analysis, different
things.
Then there's the Standard Review Plan, with an ISA
chapter. That has acceptance criteria in it and suggested
format for presenting results.
The other one is NUREG 6410, which is the accident
analysis handbook, which is consequence evaluation methods
for fuel cycle facilities, both chemical and radiological.
DR. APOSTOLAKIS: There is something that is not
clear to me.
You mentioned that there is certain guidance in
the Standard Review Plan, so at least, you know, the
licensees will know where the stuff is coming from.
Isn't that the job of a regulatory guide? The
Standard Review Plan is for internal use. Is there a
regulatory guide here?
MR. MARKLEY: The Standard Review Plan is publicly
available, George.
DR. APOSTOLAKIS: It is publicly available.
MR. MARKLEY: The NUREG is available for the
licensees' use.
DR. APOSTOLAKIS: How come there is no regulatory
guide?
MR. SHERR: Historically, we have had a standard
format and content guide as a companion document to the
Standard Review Plan, and the decision was made at some
point that, in many respects, those two documents are
redundant and that the standard format and content guide
doesn't provide as much detailed information.
So, basically, the Standard Review Plan is also --
serves also as a standard format and content guide.
DR. APOSTOLAKIS: Does NMSS issue regulatory
guides?
MR. SHERR: Yes.
DR. APOSTOLAKIS: But in this case, the Standard
Review Plan really plays that role.
MR. SHERR: Yes.
MR. DAMON: Yes. That was an explicit decision.
I remember when they made it. They said, you know, we're
going to make the -- in fact, it's just a general policy not
to try to do this type of guidance with regulatory guides
but to either do it -- it's either in the Standard Review
Plan or it's a NUREG, one of those two.
MR. SHERR: The Standard Review Plan has been in
development for about as long as the rule has been in
development, since '93, and it was published as part of the
proposed rule, and in fact, we received more comments on the
Standard Review Plan than we received on the rule itself.
DR. APOSTOLAKIS: If it's been in development
since 1993, how come it hasn't been reviewed internally by
the ACNW? This is a rule.
MR. MARKLEY: I can't tell you how many iterations
it's gone through, George, and certainly I wasn't party to
the ACNW deliberations. I don't know what has happened and
what hasn't and when the opportunities were and weren't.
You might ask some other players where that occurred.
DR. GARRICK: Are you aware of anything, Rich?
MR. MAJOR: I'm not aware of anything. The ACNW
has not focused on fuel cycle facilities, especially fuel
fabrication plants.
DR. APOSTOLAKIS: I see.
DR. GARRICK: Our charter has changed. Our
charter certainly includes such facilities, and so, we're
not maybe keeping up with due process here.
DR. APOSTOLAKIS: Okay.
DR. GARRICK: But I am struck by the fact that,
when I look at SECY 99-147 and I look at the background
paragraph that talks about a near criticality incident,
etcetera, etcetera, has prompted the NRC to evaluate its
safety regulations for licensees that possess and process
large quantities of special nuclear material and so on and
so forth.
The staff concluded that, to increase confidence
in the margin of safety at a facility possessing this type
and amount of material, a licensee should perform an
integrated safety analysis, and then it goes on to say what
an ISA is, and no reference really to risk assessment in the
traditional sense.
So, this obviously has a chemical heritage to it,
and is quite separate from picking up on the NRC legacy of
advancing towards a risk-informed regulatory practice that
has been largely influenced by, to be sure, reactor
applications and more recently, performance assessment
applications of nuclear waste.
So, this middle ground here of large fuel cycle
facilities, fuel facilities and processing facilities and
UF-6 conversion facilities has kind of been in a vacuum as
far as getting lots of attention from either the ACRS on the
one hand or the ACNW on the other hand, and given that it's
rooted in the chemical field and that the chemical industry
has been driving it for the most part, it's gone a different
direction, and I don't think it's anymore complicated than
that.
But I think this has been very constructive. I
think this has helped us focus a little bit on an area that
maybe, you know, the advisory committees have --
DR. APOSTOLAKIS: So, you are responding to an SRM
dated December 1, '98. Is that really what this is?
MR. SHERR: No, I think it was July 8, '99. The
package you have is the proposed rule package. An SRM was
issued as a result of that on, I think, July 8th.
DR. APOSTOLAKIS: Of last year. But the whole
history started a long time ago.
MR. SHERR: It started in '91.
DR. APOSTOLAKIS: So, an extra two years wouldn't
hurt, would it?
Okay.
DR. GARRICK: All right.
Let's go ahead, if we haven't completely
disrupted.
MR. DAMON: I'll go through this very fast, and
then just stop me when you want to talk about something.
This is what an ISA does. It uses systematic
methods to identify hazards, namely just where in the plant
are there things that are hazardous, because that's --
again, remembering the roots of this, the problem was they
weren't addressing chemical safety at all at these plants.
They did not have any kind of documented chemical safety
analysis, controls, the NRC was not regulating it, and so,
we're trying to get a documented safety analysis on the
record here, first identify where are the hazardous
chemicals and the radiological materials, then do what we'd
be more familiar with, fault trees or whatever, identify
actual specific accident sequences, and identify the
consequences and the likelihood of those accident sequences,
and specifically, here's another item that we're interested
in, identifying items relied on for safety.
This may sound sort of strange to say a statement
like this, but if you go to a facility -- even if you look
at the old-style documentation that are nuclear criticality
safety analyses, which they've done for years, and you ask
yourself what things in this process are they relying on for
safety, very often, when I've gone and looked at them, they
are not documented.
They are relying on certain characteristics of the
process which is not in the documentation, and without that
characteristic -- in other words, you take the GE event. It
was a solvent extraction process, and the output from the
process went to a holding tank that was safe geometry, it
would be sub-critical under any conditions, and the tank was
relatively small, and what had happened is they increased
the throughput in the plant such that the operator was
having to empty that tank about every hour or so because it
was too small and would get filled up from the process.
Well, there's a big difference in the safety of
that -- and so, what they didn't understand was the safety
of that process depends on the demand rate, if the guy is
under a higher and higher demand rate until finally they had
a process upset which caused him to -- there was a control
valve malfunction in the process, and during the process
when that control valve was malfunctioning, he was still
transferring -- he had to transfer every hour the contents
of this tank, and so, the process design -- they didn't
realize it depended on the demand rate, and they needed to
lower the demand rate by increasing the tank capacity, and
that's what they did. After the fact, since '91, they've
built a lot of very, very, very large safe geometry tanks.
So, now they don't have to transfer every hour.
They can sit there and wait for days until they do a
transfer and make sure it's done right.
So, they don't understand what they're relying on
for safety, and it's the major thing that I think ISA will
accomplish here.
They will put it down in writing and they will
send us that list of what they're relying on for safety.
We've never had that before.
We have never had here in this agency a list of
what they're relying on for safety in their plants.
DR. APOSTOLAKIS: Which is really similar to what
the Commission did when the power industry was resisting
PRA. They asked them to find the vulnerabilities. Isn't
that another way of putting it? And then the industry
realized that the only way to do it was to use PRA. I mean
it was a hugely successful program from that point of view.
It spread the technology, really.
I mean the individual IPEs -- some of them are
really not very good, but you know, the learning process was
tremendous, and that's maybe what we need here.
MR. DAMON: Again, it's a -- like you say, it's a
process of them learning what they don't know by doing it.
DR. APOSTOLAKIS: Exactly. That's very useful
background, yes.
There is an interesting view-graph a little later
that says likelihood -- is that before or after where you
are -- likelihood, evaluation, acceptance criteria. I don't
know where we are now.
MR. DAMON: There's three different things that --
when the staff receives an ISA summary to review, what we're
going to be looking for in there is the completeness of
identifying all the accidents, the correctness of the
consequence evaluations, and the adequacy of the method they
use and the criteria they use for judging that things are
highly unlikely or unlikely.
That guidance is in the Standard Review Plan
chapter.
The completeness is address by the -- for one
thing, the methodologies.
Do they use these methodologies that we've told
them to use in selecting it with a flow chart in NUREG 1513
and have they applied it each time to each process in a
correct manner, and of course, then, we'll have the staff
review the results and see if they think that they've picked
up on all the accidents.
NUREG 1513, like I say, is primarily focused on
identifying hazards and accidents. It's got methodologies.
It's based on the AICHE red book on complying with the OSHA
rule and has a flow-chart for selecting the correct process,
and it has a long list and includes actually quantitative
PRA as one method in there.
DR. APOSTOLAKIS: Yeah, but you know, I've seen
the what-if stuff. I mean it was presented to me as if it
was a big deal.
I think it depends very, very much on the hazards
you are talking about. In some instances, you know that the
hazards are not very large. Maybe a quick what-if analysis
is good enough. It's qualitative. You ask people,
knowledgeable people, what can happen here and there.
But in light of what this agency has done to
promote risk assessments and so on, this is really a trivial
Mickey Mouse kind of thing.
So, I am not sure that it should be one of the
acceptable methods, and the recommendations that come out of
it really are, again -- I mean if you're talking about a gas
station or something like that and you want to avoid
accidents, maybe it makes sense, but not for a facility that
has nuclear materials in it, and the hazards -- you know, I
mean they have been glorified by the chemical industry, and
for us, it's a starting point of a PRA.
I mean no PRA analyst will start doing PRAs
without doing some form of hazard first, you know, what if
this fails, what's going to happen, let me understand the
system, structuring the scenarios that we talked about
earlier.
MR. DAMON: Well, I think that the flow-chart in
NUREG 1513 -- that's what it's intended to address. It's
intended to prevent them from doing that, and I'm not sure
it's going to be successful.
We're going to have to arm-twist them into it.
We're going to have force them. The staff is going to have
to tell them you cannot do what-if on a complex process, you
know.
That's only appropriate for -- in fact, my own
view is it's really just a front-end, it's a screening,
brainstorming thing you do on the front-end, and then you go
ahead and you do your fault trees and event trees.
DR. APOSTOLAKIS: That's right. But this industry
is dominated by chemical engineers, isn't it?
MR. DAMON: Yeah, I would say mechanical and
chemical.
DR. APOSTOLAKIS: Yeah.
MR. DAMON: There are criticality engineers who do
the criticality safety, but they're primarily, you know,
reactor physics calculators.
They're not -- the discipline that is missing in
these plants, in my own opinion, is reliability engineers.
They do not have reliability engineering as a discipline in
any of these plants. They don't know the subject.
So, like I say, if you look at the rule, the
bottom line is consequences have to be understood
quantitatively. So, they do have to do calculations for
that.
There's a guidance document on it, this NUREG that
was generated a few years ago. It's a summary of the
current state of the art in methodologies for calculating
consequences, both chemical and radiological.
Really, when you look at what the consequence
levels are, the intermediate high defined in the rule, you
only need a gross estimate in order to figure out where
you're at, and then, to know whether you're highly unlikely
or unlikely is the appropriate category.
One of the things about this is -- about these
methods is a lot -- I would say most of the accident
sequences will be nuclear criticalities for which
consequence evaluation really doesn't need to be done.
It's clearly going to be a high consequence event
by definition in the sense that you can't preclude the fact
that someone might be standing there and might get killed.
Therefore, the process has to be protected at the level of
highly unlikely.
DR. APOSTOLAKIS: Now, let me understand what this
means.
The applicant defines -- you mean the applicant
will assess the frequency, qualitatively perhaps, of
sequences and declare them as unlikely or highly unlikely.
The applicant will not define what is unlikely the way you
do in the SRP. That's your job.
MR. DAMON: Right. Well, the way we refer to it
is he can establish a method which has criteria in it for
what constitutes highly unlikely in his view, and the staff
will then have acceptance criteria in the Standard Review
Plan as to whether we accept that criteria.
DR. APOSTOLAKIS: You mentioned in the SRP that
highly unlikely means 10 to the minus 5 or less.
Now, what if an applicant comes and argues that 10
to the minus 4 is still highly unlikely? Is that what this
means, defines?
MR. DAMON: Yes, it does.
DR. APOSTOLAKIS: This is kind of unusual, isn't
it? I mean this should be the job of regulator, what is
acceptable.
MR. DAMON: Yes. That's what I say. The Standard
Review Plan says what we regard as acceptable.
So, there's no point to them coming to us and
telling us 10 to the minus 4. We've already said --
DR. APOSTOLAKIS: So, the applicant really doesn't
define it.
DR. GARRICK: Likelihood has no relevance except
when associated with a particular consequence.
MR. MARKLEY: George, I don't think it's
appropriately defining; it's categorizing.
DR. APOSTOLAKIS: But that's my concern. Does the
word "define" mean categorize or actually define what's
acceptable, what's unlikely, high unlikely, because if it's
the second, I think it's the job of the NRC to do that, not
of the applicant.
In other words, the applicant should be assessing.
In other words, they should be saying yes/no.
MR. MARKLEY: I don't know that I agree with that,
George, because I mean I still think the licensee has the
obligation to determine it and the NRC the obligation to
confirm or determine whether they would agree or not.
DR. APOSTOLAKIS: But the applicant will never
tell you what's acceptable.
MR. DAMON: Let me clarify why you get in this
dilemma.
If we were doing it quantitatively, there would be
no -- if we were going to insist that things be done
quantitatively, there would be no question about, it would
be very simple.
DR. APOSTOLAKIS: Yes.
MR. DAMON: But since what we anticipate is that
they won't do it quantitatively, what they'll do is do it
qualitatively, if you try and define a scheme by which
they're going to categorize controls by their qualities,
they're going to have to explain to us what this scheme is
by which they're going to evaluate something and say, yes,
this is highly unlikely because it has this characteristic,
this characteristic, this characteristic, therefore it's
highly unlikely.
DR. APOSTOLAKIS: But that's an assessment, that's
a categorization.
MR. DAMON: Yeah, it's a categorization, right.
DR. APOSTOLAKIS: That is okay.
MR. DAMON: And we're going to ask them to do this
categorization and then tell us which ones of these do you
consider to be highly unlikely. It's a misleading term.
The natural interpretation is it should be a number. So,
they're going to develop some kind of method.
I've divided the potential methods into three.
They could do it quantitatively. He could do a PRA, and
they could, therefore, define a likelihood by a frequency
per year or some analogous quantitative measure. The other
extreme is purely qualitative by the characteristics of
whatever the process design is.
The one in between is the BWXT method, the method
they used, which one way of describing it is to say it's an
order of magnitude, a quantitative, or you could say it's a
qualitative method that assigns index values to likelihood.
DR. GARRICK: They do a lot of this in the marine
field, as well, particularly in the offshore. They use
exactly the same language, and they have relied heavily on
what they call indexing methods, and the UK rules that have
come out with respect to safety case requirements for
offshore platforms have adopted a kind of a similar set of
descriptors and terms, and all of that does have its roots
in the chemical industry.
MR. DAMON: As I said, this index method is the
method that BWXT used, and it's what we would like the
others to use. It remains to be seen if they will do it.
One of the problems has been, as I said, BWXT's
submittal is proprietary. They, in fact, wouldn't even
submit their methods document.
So, I don't even know the scheme that they used,
all I have is the results, and so, when they -- of course,
that will change when the rule goes into effect, I can
demand the methods document, but they were very tight-fisted
about this, and fortunately, it seems to be getting away
from that.
They seem to be working through NEI, working
together more, or maybe they're going to iron this out and
they will come to use BWXT's method.
Like I said, a quantitative method is not
required, but it's permitted, and that's the way it's stated
in the Standard Review Plan.
This index method is the one that's actually been
used.
DR. GARRICK: It would be much better there if you
said that it's encouraged, because saying permitted makes it
come across as a inferior method to the other methods.
MR. SHERR: It is sort of encouraged in the sense
of what the Standard Review Plan identifies as an example is
this semi-quantitative approach, and so, in that way, that's
the only thing that we've identified so far.
The industry has been saying they would like us to
develop another example that's purely qualitative, and we've
been struggling with that.
DR. GARRICK: Well, what they're going to discover
is the same thing that the NRC discovered when they started
out with their IPE program thinking that -- and justifying
it principally on the basis that it was less cost, and they
have ended up with models that are at greater cost than the
kind of full-scope PRAs that were being advocated in the
late '70s and early '80s.
They'll just make the same discovery eventually,
that the best way to do this is, in fact, to build a
quantitative model and to be creative about how they build
that model in order to achieve the cost control that they
want and that all of this other stuff will hopefully go by
the wayside, because it's just a way of dancing around and
avoiding hitting it on all fronts.
NASA has gone through the same thing. They have
resisted probabilistic methods from 1959, from the time that
GE presented a calculation that found its way in Congress
that the probability of getting a man to the moon and back
was something like 5 percent, and they got embarrassed by
it, and the then-administrator said we will never use
probabilistic methods again.
Well, they're using probabilistic methods, and
they're using them increasingly extensively, and eventually
they'll come around.
There is now a risk model for the shuttle, and so,
unfortunately, it seems to be the way that it has to go,
that everybody has to satisfy themselves that they have
another way, and I think that, until you answer the risk
question, you know, you've not answered the margin question.
MR. DAMON: I agree, and my own view -- this
resistance to PRA is not the staff. It's not the NRC staff.
It is the licensees. They insist, oh, you couldn't possibly
do this stuff, and they just don't understand.
Like I say, part of the problem is they don't have
people that have ever done this, so they don't understand
how they could do it.
You know, if they had on their staff people who
had done it, they would understand, yes, you could do it.
DR. GARRICK: Yeah. So, it will come, and maybe
this is just as well, that it has to come in this fashion.
The marine industry is going through the same
thing. When they finally got pushed to the wall and they
did the Prince William Sound study, which was pretty close
to being a full-scope probabilistic risk assessment, and
they've learned a tremendous amount from that study, much
more than all the rest of the studies they've done, put
together, about risk.
So, you know, it seems to be a pattern that is
unavoidable, and we're going through it now in the chemical
field.
MR. DAMON: I agree. What I see when I see the
analyses, unless the system is extremely simple, what will
happen when they use these non-quantitative methods is they
will simply get the system model wrong. In other words,
they're not -- because they're not used to formulating what
I would call a quantitative reliability model, they don't
understand the equation, and if you don't write the equation
down, you don't know what you're relying on for safety in
the system.
So, they get everything wrong. They don't succeed
in identifying -- for one thing, when a redundant system --
they don't properly understand the virtue of limiting the
down time by surveillance method or having fail-safe
equipment or self-announcing failure.
You know, the idea that when -- if you have two --
a redundant system and you get the first failure, you've got
to be aware that that system is in a vulnerable state so
that you can render it safe.
You've got to limit the down-time of that initial
failure.
They don't understand that, so they don't do
anything about it in some cases, and in some cases they do,
they've figured it out by just sort of experience, that, you
know, you need to have something to recognize when the
machine breaks, but they don't understand the concept, they
don't understand the math behind it.
DR. GARRICK: How are we doing? According to the
agenda, we're due for a break in about 10 minutes. Are we
within 10 minutes?
MR. DAMON: Yes.
DR. GARRICK: Okay. Good.
MR. DAMON: The trouble with qualitative --
DR. GARRICK: We say this like it's your fault.
DR. APOSTOLAKIS: Well, he has been so slow.
DR. GARRICK: And we apologize for our
interruptions, but we're learning a lot.
MR. DAMON: The idea here is how is the staff
going to judge when the applicants send in their version of
a likelihood evaluation whether this thing all makes sense?
My own view is, if you have any doubts, you're
going to do your own quantitative analysis of whatever the
situation is, but one way of looking at things is to
categorize things by the various qualities that you rely on
to achieve a high reliability, high availability type of
system, and this is a list of the different factors that
need to be evaluated, and if the applicant hasn't considered
these things, they don't know how to put the whole thing
together, then they're going to get the wrong -- an
inadequate answer.
For example, the thing I was mentioning about
limiting down-time is what I'm calling here an availability
measure.
That's certainly something they need to address.
They need to tell you in the analysis what surveillance
they're doing on the equipment to detect that it's in a
failed state -- functional test, monitoring, operator
observation, or what, and of course, independence is related
to, you know, things like common cause and diversity, and
there's guidance in the Standard Review Plan telling the
reviewer to look and see, have they looked support system
failures, you know, power supply to the system and stuff
like that.
If they haven't done that, then they probably
haven't got a system that is going to meet the standard for
highly unlikely.
The reason the number 10 to the minus 5 and that
quantitative stuff was put in there is we asked somebody --
we asked one of the applicants, one of the licensees, what
would they consider to be a highly unlikely for a single
accident to occur, and they said, well, less than once in
the life of a plant, and at that point, I realized they
didn't understand the concept that we're talking about each
accident here, that there's thousands of accidents, and that
if it was once in the life of a plant times 1,000, they
would be having them every month, you know, and they don't
understand things in that way.
So, that's why that kind of guidance is in there,
if they come in with a definition like that, but what we
expect is these qualitative things.
These graded management measures are all the
things like QA, maintenance, configuration management. We
expect them to specify what they're going to do to these
items relied on for safety that's going to make them
reliable and available and to commit to them in writing and
submit that list of items relied on for safety that
specifies all these qualities that they're going to
maintain, and admittedly, this doesn't look very elegant
compared to doing a risk assessment, but compared to where
they were, you know, in 1991, this is a big step forward to
just get them to list all the items relied on for safety and
send it to us.
This is the thing that they're accustomed to, and
one of the reasons that they practice this concept of
qualitative evaluation is it goes back to the fact that the
only kind of safety analysis they did was criticality safety
analysis, and in that field, the people that write the
standards on that, many years ago, came up with the idea of
a thing they call double-contingency, and there's the
double-contingency statement. It's just redundancy.
They're just saying don't rely on any single
control, and they learned this the hard way. Back in the
'50s and '60s they had a criticality accident about every
two years until finally somebody says, you know, maybe we
should upgrade the safety of these things, and they came up
with this.
DR. APOSTOLAKIS: Single failure criteria, right?
MR. DAMON: Single failure criterion.
So, this is what they have been working to for the
last 30 years, and they haven't had a criticality in a NRC-
regulated facility in the entire history of the agency and
they haven't had a criticality in DOE since the mid-'70s, I
believe.
That was a shielded criticality.
No one has died in a criticality since the '60s.
So, there was a sudden improvement when they
adopted this concept.
So, what we're trying to do is get them to take
one more step here, do a little --
DR. APOSTOLAKIS: Do you think it would be a good
idea to ask everyone to try to identify plant
vulnerabilities?
MR. DENNIS: That is part of what is specified.
In fact, it's in the rule. They are required --
DR. APOSTOLAKIS: They will have to do it.
MR. DENNIS: They are required to identify
vulnerabilities and to correct them.
DR. APOSTOLAKIS: How much time do they have to do
that?
MR. SHERR: Four years.
DR. APOSTOLAKIS: Four years. And they will
submit the ISA to you for review?
MR. SHERR: ISA summary, right.
DR. APOSTOLAKIS: Summary. It's IPE all over
again, guys, It's really all over again. It's IPE.
Somebody must love it very much.
MR. DENNIS: Because of the number of processes
involved, these analyses actually are quite voluminous. It
takes about two bookshelves to three bookshelves full of
stuff or more to cover one of these plants. It's quite
bulky. So the ISA summary, we might get down to half a
bookshelf.
DR. GARRICK: While you were out, I was pointing
out the IPE started out as a simple solution that was
increased in scope with such things as external events and
later with large early releases, et cetera, et cetera, and
until you clearly see that, yes, you could have done a very
competent PRA, full-scope PRA for what's been spent.
DR. APOSTOLAKIS: We understand all this.
DR. GARRICK: It's a little unfair for a George
Apostolakis and John Garrick to be ganging up on you on this
discipline. We clearly have our prejudices with respect to
the use of PRA.
Is that it?
MR. DENNIS: That's it.
DR. GARRICK: That's very good. Well, we are
interested in this and see how it evolves, because it does
have a very familiar ring to it in the IPE world. So I'm
sure there's lots of lessons to be learned there. But I
would sure be a lot happier if the rule was not so sensitive
against the use of PRA as a preferred option for complying
with independent or integrated safety analysis.
Very good. Any other --
DR. APOSTOLAKIS: You say that you do have one of
the ISAs, the BXT?
MR. DENNIS: BWXT used to be B&W, Babcock &
Wilcox, only they changed their name and they put an X in
it, for some reason.
DR. APOSTOLAKIS: It's like LAX. Do you think we
can have a subcommittee meeting, a joint subcommittee
meeting reasonably soon, where we can discuss the ISA and
the details? Because what you gave us today is really a
presentation that one would make before -- they will be
invited, too.
DR. GARRICK: But I think if we heard a
presentation of an ISA of a specific facility, then we'd
develop a much greater sense of what it's all about and also
may be able to make some constructive ties with what is
required to upgrade it to a PRA.
STAFF: If this is a question directed at the
staff, the answer is yes.
DR. GARRICK: Yes.
DR. APOSTOLAKIS: Would the industry be willing to
come?
STAFF: That I don't know. We would certainly
work with them to see if we could get them to participate.
DR. APOSTOLAKIS: If you asked them today, they
will come.
DR. GARRICK: Thank you very much. We're going to
take a 15-minute break.
[Recess.]
DR. GARRICK: We'll come to order. We are now
going to hear about why they sent us this big book on
byproduct material risk analysis, and three volumes, and I
think you ought to tell us about it.
Would you introduce yourself and tell us what you
do, et cetera, first?
MS. ULRICH: Sure. My name is Betsy Ulrich. I'm
a Senior Health Physicist in Region I. I do both licensing
and inspection of materials activities. A few years ago, I
was asked to take part on the -- let's see, what was it
called at the time -- nuclear materials byproduct risk
review group, which we shortened to RRG and you may see that
in the handout occasionally.
That's what I'm here to talk about today, the risk
assessment that was done of byproduct material activities.
There's three things that I would like everyone to
remember about this study. This particular slide is not in
your handout, but everything that's on this slide is.
The first is that in this NUREG and in our report,
you will see numbers, and the use of numbers implies or may
imply that there is great accuracy.
In fact, the numbers that resulted in the risk
assessment for radiological risk have uncertainties that are
on the order -- orders of magnitude. So because we have
numbers doesn't mean great, great certainty in this case.
DR. APOSTOLAKIS: Let me understand that.
MS. ULLRICH: Yes, sir.
DR. APOSTOLAKIS: The way I read the book is that
there is variability on several orders of magnitude if I
look at the numbers for one activity from facility to
facility or maybe across activities. But if I specify one
activity, is the uncertainty orders of magnitude?
MS. ULLRICH: Yes, it is.
DR. APOSTOLAKIS: And why is that?
MS. ULLRICH: Because even among the systems, as
we define them, there is great variability, and I will talk
about that in the presentation. So if you want to hold
that, I think we'll get to it.
The second point that I want to make is one that
has confused many of the people that I've presented some of
this information to in the materials community, and that is
our risk values have units of millirem per year. It's
because when we defined risk, we said this is the
consequence in terms of dose, millirem per year, multiplied
by a probability of some event happening.
The resulting units are millirem per year. People
look at the tables, don't read the word risk, they see the
millirem per year, and they said you don't get doses like
these in materials activities. And so it's something that I
have to stress to a number of people.
DR. APOSTOLAKIS: So it's the expected dose.
MS. ULLRICH: Yes. And the third is that we did
not make any judgment in the study as to what is acceptable
risk. That is something that probably needs to be done, but
it was not done here. We simply assessed what we believed
the risk values to be.
These are the topics that I will move through,
some more quickly than others, and certainly spend whatever
time you want in the different areas. Who we are, what the
scope of the risk assessment included, what categories of
radiological risk we assessed quantitatively, how we did the
risk assessment or how the contractor did the risk
assessment, since they did the real guts of that work, and
where our uncertainties are, how we used the consequence
information, and what evaluations the risk review group did
of the NUREG CR information, and what we conclude the
results are.
The risk review group had two goals, to identify
and document a technical basis for a risk-informed approach
for regulating byproduct materials. That included all Part
30 activities. So those are activities covered by the
regulations in 30, 31, 32, 33, 34, 35, 36, and 39. And to
develop a graded approach for regulating them using this
risk information.
We had five persons on the group; two health
physicists, one from the NRC, that was myself, one from the
State of Colorado. We also had persons with experience in
risk assessment, engineering and human factors. So that was
the core group, and our job was to figure out how to cope
with this project, to find a contract to assist us with it,
oversee what they did, work with them, and try to make some
conclusions out of this as to how we can use this
information for materials.
DR. APOSTOLAKIS: Now, the risk assessment person
was from the reactor arena?
MS. ULLRICH: John Randall, actually. So yes.
As I said before, Parts 30 through 36 and 39, again, I have
given this presentation to some other people, so I find
myself riding my little hobby horse about you multiply dose
times the probability and you get units of dose, but it's a
risk value in this study.
We defined what we considered discreet systems for
materials activities based on similar uses, quantities and
forms. This is the obligatory slide that's difficult to
read. This pretty much covers the range of materials
activities. We did have pointed out to us in the comment
period that we missed a couple of items, like nuclear
laundries, decontamination services, but I think overall,
we've got a good scope there.
Why some of the uncertainties are still high, even
with a system like fixed gauges, there's a wide range of
gauges, there's a wide range of activities used in the
gauges, how they're used, where they're used. So there's
uncertainty when you come up with one number for that
category.
One correction to this, and that is system four.
It should be nuclear medicine, generator only, and this is
because there are some hospitals that use generators,
molytech generators, and more and more now do not. So if
you wanted to assess the risk for a group that uses a
generator, you would add systems four and five.
So the four is generator only and then five is all
the nuclear medicine involved with administering those
dosages to patients.
Scope of the risk assessment. For the
radiological risk, we looked at what is the risk to workers,
what is the risk to the public, what is the risk under
normal conditions and off-normal conditions. There's
actually another set of categories, which is risk to
individuals and an industry-wide risk.
It did not include doses to patients. That's real
important for people in the medical community to understand.
It's also important for the people in NRC to understand,
because a lot of our regulations involve misadministration
to patients. That was considered out of bounds, out of the
scope of this project. So that's not included.
We didn't look at transportation, covered under
Part 71 or DOT, and we didn't look at developing future
technologies.
The real nice thing, and this will come up again
later, is that along with the NUREG CR, the contractor
developed the database that could be used for revising
systems or adding new systems, as we have more information
about new technologies.
DR. GARRICK: Having done this study now, I
suspect you'd be able to reduce these 40 systems down to a
much smaller number.
MS. ULLRICH: I don't think so.
DR. GARRICK: You don't think so?
MS. ULLRICH: It was real difficult even coping
with the variations within these systems. It was an
extraordinary amount --
DR. GARRICK: Well, if you were to do it by risk,
if you were to categorize it by risk, would you be able to
sort a smaller grouping?
MS. ULLRICH: I certainly think that you could
sort out systems that you wanted to look at in more detail
and more rigorously. I think you could select out the
systems with higher risks that you might want to find more
information about and make it a more certain assessment.
DR. GARRICK: Well, if you wanted to dig deeper
into those that were most important.
MS. ULLRICH: Yes.
DR. GARRICK: John, you seemed to have a reaction
to the question.
MR. RANDALL: Yes. I was just thinking. I didn't
stay with the group long enough to get to that point, to get
a chance to think about sorting the risk numbers.
The group functioned for a while as a group and
then suddenly we weren't a group anymore. It was just
interesting.
MS. ULLRICH: There was some attrition, yes.
DR. GARRICK: I found the document to be very
useful, and the partial answer to the question that this
joint subcommittee asked early on is that you should tell us
what you think is important from a risk perspective, and
let's start from that point.
You've kind of done that now for the byproduct
side of the problem.
MS. ULLRICH: I think so. These two bullets are
really probably the meat of what we had assistance from the
contractor to do, getting a quantitative and qualitative
assessment of the radiological risk. We also attempted to
get a qualitative evaluation of some of the other risks and
all of that information is summarized on the matrix handout
that some of you may have picked up.
So you will see the bottom list of some of the
other issues we looked at, regulatory burden, risk of
contamination, the cost of decontaminating, non-rad health
risk. Those we simply didn't have the time or other
resources to pursue that in any kind of quantitative way.
So those were qualitative and based on mainly literature
research, if I recall correctly.
The matrix summarizes all of the numbers and in
all of the risk categories. These are the eight risk,
radiological risk categories that we looked at. The first
four are all the individual risk categories. The second
four are industry-wide risk.
It's not truly a collective dose. It's looking at
the population of the industry only, not the persons that
would be affected by that industry, and I'm not really sure
what to do with those numbers or how best to use that
information. It's simply clear that if you look at
industries that are large, such as portable gauges, having
many thousands of them out in use, they rise higher level of
risk, if you're comparing industry-wide risk, than they do
in individual risk.
Industries that are very small, the use of pool
irradiators, mega curie pool irradiators, you can probably
count on a couple of hands and maybe a foot how many we have
of those in the United States, very small industry. So as
an industry risk, they don't come near the top.
So I'm not really sure how we should use that
information, but we do have it at this point. The other
thing is there's probably larger uncertainties with the
industry risk, because now we're guessing how big the
industries are, and that's also a difficult thing to do.
The method that we ended up choosing for the
radiological risk assessment was probably best described as
a modified target, hazard -- hazard barrier target analysis,
where the hazard is the radioactive source. There are some
barriers that may be administrative, may be physical, which
protect the source from reaching a target, who is either a
worker or a member of the public.
The other thing to remember with this study is
that a member of the public could be a collocated worker,
somebody who is not assigned to work with radioactive
material, but may be at the next laboratory bench or may be
the flag person on the construction site near where somebody
is using a portable gauge.
So that would constitute, in this study, a member
of the public, not a worker.
DR. GARRICK: That almost lines up with level one,
two and three. In the old reactor days, we used to talk
about the plant model, the containment model and the site
model.
MS. ULLRICH: Okay.
DR. GARRICK: It's the same kind of breakdown.
MS. ULLRICH: Yes. Well, what did we have to do?
Well, we had to adequately describe the systems,
characterize the systems in a way that made some sense, that
it would include the main range of radionuclides, the range
of activities that were used in each system, and then look
at what are the barriers, what kind of shielding is there,
what kind of confinement is there, what kind of restrictions
to access are there, what's required by regulation, what's a
good practice.
That took a while to develop, again, because the
industries, even within the systems, vary and people use
radioisotopes for different things or in slightly different
ways. So it's not terribly consistent from user to user and
it's less consistent as you go from sealed to unsealed.
The unsealed users are all over the board with how
they handle stuff.
Developed scenarios or sequences of what kinds of things
happen when people handle radionuclides and what can happen.
Can they pick it up? Can they drop it? If they drop it,
does it break? If they drop it, does it spill? All those
sorts of things went into the sequence development.
Then those sequences, in an effort to simplify it
or characterize as event trees, but only in terms of success
or failure of shielding or confinement or access. The
contractor did not attempt to do that for all the individual
events that would comprise shielding or comprise
confinement.
DR. GARRICK: Betsy, in connection with the
development of the scenarios, one of the things I was trying
to figure out as I read the document is whether the
database, such as the NMED or whatever it is, drove the
structuring of the scenarios or whether the physical system
and an engineering analysis thereof drove the development of
the scenarios.
MS. ULLRICH: Where there is a system that would
be considered engineered, like a pool irradiator or
radiography unit, that certainly drove it. I think work
habits drove it, the process people go through in using,
looking at it from how do they get the material, how do they
receive it, when they handle it, what are they using it for,
how do they store it.
NMED did not drive that at all.
DR. GARRICK: Okay.
MS. ULLRICH: Okay. NMED was actually a very
limited resource for us, in many ways.
DR. GARRICK: I know that and that's why if you
were going to tell me that it was an NMED, then you were in
for some real questioning.
MS. ULLRICH: Okay. Now we start getting into
some of the interesting stuff. Determining the frequency of
sequences, that is where NMED did come in. Where we had
incidents that were required to either be reported and we
had NMED information, some of that was used to develop
probabilities for the frequency of those events happening.
One of the errors in here is that we don't have a
good handle on denominators. NMED would give you the number
of numerators, the number of reported events that happened,
but we don't always have good denominators for these
numbers, either.
Nuclear materials events database.
DR. APOSTOLAKIS: NRC?
MS. ULLRICH: Yes.
DR. APOSTOLAKIS: The equivalent of LERs?
MS. ULLRICH: Yes.
DR. GARRICK: Yes, sort of, but a little
different. It's a little more compact than the LERs.
MS. ULLRICH: It also gathers information from the
agreement states, as well, for the materials activities.
Once a frequency was determined, we could also calculate the
doses and then calculate the risk value by multiplying
those.
All that information is on computer disk. It's
the byproduct material system risk database. It's got a
file and a user's guide and that is available to NMSS. They
have a couple copies of that, and that contains all the
information that is the basis for the dose calculations and
the risk calculations.
It wasn't a trivial effort. I don't know how
these numbers compare to a PRA or to a reactor risk
assessment, but to me these numbers were mind-boggling.
Fifty-six different nuclides, 518 tasks, 4,000 normal and
off-normal sequences and over 27,000 individual
calculations, and none of that is in the NUREG.
DR. GARRICK: That's a small fraction of one PRA.
MS. ULLRICH: Yes. To me, that's a big deal. It
was a lot of effort, and I wasn't the one who had to do it.
So kudos to the people who did it.
DR. APOSTOLAKIS: Now, you're going to talk about
the uncertainties at some point.
MS. ULLRICH: Yes.
DR. APOSTOLAKIS: In the assessment process, when
you calculate the consequences, you say somewhere here that
you were uncertain about the -- I made a note on it. The
risk results are based on an average consequence for the
conditions evaluated. There can be significant variability
of risk results around the average due to the variations
from one user to another, and from one day to another.
Would you care to explain?
MS. ULLRICH: Sure. Let's take a hospital
situation, since many people are familiar with that, and a
hospital situation is actually more consistent than many of
our other material systems that handle unsealed material.
But on any given day, they may have six patients,
they may have 16 patients. If they have 16 patients,
they're going to be handling more activity than they would
on a six-patient day. They may have iodine therapy just one
day a week or one day a month. Iodine therapies drove the
dose consequences in these risk analogies.
So if you have a hospital that doesn't use iodines
at all, their risk is going to be much lower than the
hospitals that are frequent iodine users.
DR. APOSTOLAKIS: So there is an uncertainty,
then.
MS. ULLRICH: Yes.
DR. APOSTOLAKIS: Regarding the number of
activities.
MS. ULLRICH: Yes.
DR. APOSTOLAKIS: Taking place within a period of
time.
MS. ULLRICH: Yes.
DR. APOSTOLAKIS: And the reason why we're
interested in that is because if you have N activities, then
there is maybe a high probability of human error or
something like that, because people have to do many more
things.
MS. ULLRICH: Yes.
DR. APOSTOLAKIS: This is not the typical
uncertainty that you find in PRAs.
MS. ULLRICH: No.
DR. APOSTOLAKIS: This is different. This is, in
the parlance of some of us, aliatory. The uncertainty
regarding the frequency of the initiator, for example,
that's different. That's epistemic.
So I'm really wondering how you've coupled those
things in your event trees. Do we have the event trees and
I didn't look at them?
MS. ULLRICH: No.
DR. APOSTOLAKIS: Is it possible to get an example
of a calculation that will walk me through this kind of
thing? Because I'm really curious to see how you combine
the two. It's something that is not done normally.
MS. ULLRICH: I've got two victims in the back
that I can pick on for a response to that.
DR. APOSTOLAKIS: Yes. Who are they? Mr.
Youngblood.
MS. ULLRICH: Yes.
MR. YOUNGBLOOD: The right choice is actually Mr.
Schmidt.
DR. GARRICK: You have to say who you are.
MR. SCHMIDT: Bob Schmidt, with Scientech. I was
pretty much the lead on the risk analysis. We did not do
any uncertainty analysis. Everything was calculated
basically as a point estimate of numbers to get the
frequency and to get the consequences. There was no
uncertainty analysis. All of the statements about
uncertainty are judgments as to what the variability might
be, what the uncertainty, but there's all kinds of
variation, trying to avoid getting into trouble with the
right terms.
When you analyze the system, the source strengths
can be very large within a system. One user can use it one
way, one frequency. Another one can stand further. You
have to determine how far away from it he stands, how often
does he drop it, does it open up, what are the airborne
release fractions.
There are so many parameters, that we did not do
an uncertainty analysis. It was just a point estimate, a
best estimate that we could make based on the available
information.
Some of the data, if you look at the normal risk,
that's pretty good, because we have data on normal risk.
The radiographers get a risk or an exposure per year which
is recorded and which is reported to NRC.
On the other hand, some people don't, it's not
reported. Accident risks are obviously -- where we knew
there was an accident, we would -- and we got a consequence
for that accident, we'd kind of go look at what was reported
in NMED; are they reasonable or not, yes, but we didn't do
any uncertainty analysis.
DR. APOSTOLAKIS: Now, when you say you didn't do an
uncertainty analysis, I guess you mean you didn't do an
uncertainty analysis in the PRA tradition, where, again, you
consider the uncertainty in the frequencies of the
initiators, the unavailabilities of systems, and so on, the
epistemic part.
But since here you have aliatory and it makes a
difference in the model, I wonder how you would do it. I
mean, you could still do it in a point estimate basis, but
you still have to consider cases like do they have one
patient or six. Is that in the event trees, the number of
patients and the consequences?
MR. SCHMIDT: There was an assumption about we
gather data and try to determine the frequency of use in a -
- generally, it was kind of a maximum facility. It was a
facility that used -- did this activity, from talking, in a
limited sense, to a few licensees and we had restrictions
there, how many times would they do it in kind of a maximum
case in a day, how many times a year, what was the source
strength, and that's the way it was combined.
DR. APOSTOLAKIS: Increase in probability of human
error because of the simultaneous or concurrent activities
was not included.
MR. SCHMIDT: No. We didn't get into that. If we
had data on how many drops, the issue about there's no
denominator and getting a probability of a spill, that would
kind of enter in and be taken out, because how many spills
did you have in a year, we knew, but how many activities in
a year, we didn't know, but we put it into the numerator and
in the denominator.
The numbers for the industry, though, are better,
because we had all the -- if the reporting is accurate, how
many occurrences occurred through the whole industry, how
many people are out there using them, that's an uncertainty.
DR. GARRICK: But it does sound like, A, you
considered the use of the facility, the frequency, the
frequency of the use, and, B, you considered the nature of
incidents per use.
MR. SCHMIDT: Yes.
DR. GARRICK: And that frequency was probably
influenced by the use frequency, was it not? That is to
say, if it was extensively used, you might make an
adjustment for there being more incidents per use than if
it's used infrequently. Did you make any of those kind of
adjustments?
MR. SCHMIDT: I can't recall any case where we
made a judgment that a facility that did a lot of this work
had a greater or a lower frequency of occurrences than one
who did just a few. We did not get that sophisticated. We
had enough trouble getting one number, much less a --
DR. GARRICK: But that would be one place where
you would come close to an initiating event analog, is if
you considered those kinds of things.
DR. APOSTOLAKIS: It still would be very
illuminating to see a detailed analysis for two or three
cases, different cases, if we can get that.
MS. ULLRICH: We have the system 24 walk-through,
which is probably about as close as that would get, Bob.
DR. GARRICK: Okay. Go ahead.
MS. ULLRICH: Okay.
DR. GARRICK: I found this study very interesting,
by the way. It was very informative and illuminated one of
the issues that is very important in the materials field,
and that is the contribution to risk of operations versus
accidents, and sort of rather dramatically indicates the
great differences here between this problem and, say a
reactor problem and the presentations of that, even though
it was very qualitative and non-uncertainty, was very
helpful in a risk communications sense.
MS. ULLRICH: Okay. That's good. Since we've
talked so much about uncertainties, I don't think we need to
spend too much time on this, but I would say there's
uncertainties, or perhaps variabilities or variations is the
better term here, in what we know about the systems.
DR. APOSTOLAKIS: This is a very important point,
because there are two kinds here that appear to be very
important. One is this randomness in the number of uses or
other things and then this other one is of the state of
knowledge type, where you really don't know the numbers.
In a PRA, when we say uncertainty analysis, we
mean the second.
MS. ULLRICH: Yes.
DR. APOSTOLAKIS: Because everything else is
frequencies, exponential distributions, straightforward. So
I would really be curious to see how you guys handle this or
in the future perhaps how you will handle it.
MS. ULLRICH: Variabilities in the information we
had about the systems, variabilities in the dose
calculation. Probably external dose calculation is of
better certainty than internal dose, but is still the choice
of how far away is the person, how long do they spend there,
that sort of information.
We use the alloys from Part 20, which is ICRP-30
based. We've had people argue with me about that shouldn't
be the best way to do it. As far as internal dose goes, one
of the conversations I had with Charlie Minehold was how
good are internal dose models, and he said, well, for
tritium, you're probably good for a factor of two or three;
for everything else, it's up in the air.
So there are uncertainties in the dose modeling.
Just because we can crank numbers in a computer doesn't make
them particularly good numbers all the time.
The third category is uncertainties in the
frequency or probability, likelihood, whatever you want to
call that term, and that's what you were talking about
before; how often do things happen, how well do we know
that. So those were the --
DR. GARRICK: You talk a lot about uncertainty,
but you don't do anything about it.
MS. ULLRICH: It was really -- I'm certain that I
didn't know enough about it. There was nothing we could do
rigorously for this.
DR. GARRICK: I understand.
MS. ULLRICH: There's too many unknowns and given
the time we had.
DR. APOSTOLAKIS: We should move on.
MS. ULLRICH: Well, then I'll do that. One of the
things that I do want to emphasize is that we have the dose
calculations first, the consequence, and that information,
looking at where do you get the big doses, was what -- was
the information that was used to say what things do we have
to regulate and make sure are in place, what barriers have
to be there with very high assurance, with high assurance or
with moderate assurance.
So when the NUREG document talks about where our
regulatory options should be, what areas should we regulate,
it's based on what things gave you big dose. And that, I
think, is important for people to understand if they're
going to use this document.
The risk numbers alone don't tell you everything.
Where the doses are tells you what barriers need to be in
place.
Not a big surprise for the sealed sources, one of
the barriers that has to be there with very high assurance
is the integrity of the source encapsulation. That's
something that's a function of the manufacturer, not the
person who uses the source. It's got to be manufactured
right to begin with and then they can begin to abuse it and
run them over with steamrollers and the other interesting
things that happen with some of our sources.
For most of the unsealed materials, the major
barriers were prevention of loss or abandonment, and that's
a big one for the sealed sources, as well, as anybody who
has been in any of the steel industry meetings will hear
about, and preventing accidents to the material, and both of
those involve a lot of administrative barriers, as well as
physical barriers.
The risk review group did also do a survey of
inspector and licensing personnel. We had hoped originally
to get some information that would help us with the -- the
contractor with the risk assessments. It didn't get done
quite in time. They ended up not being able to use any of
that information, but then I used it as a sort of test, is
the opinions of inspectors and license reviewers about the
safety of these different systems and how frequently they
have accidents and what kind of doses they get, in line with
what the NUREG calculations showed.
On the whole, it was pretty good. There were some
glaring differences, but. These were the kinds of
evaluations that were done with the material and all of this
is reflected in some of the tables you have, selected tables
at the end of the handout.
Let me deal with that first issue, and that is
looking at the issue of do you look at two significant
figures, do you look at one significant figure, or if the
uncertainties are really on orders of magnitudes, do you
look at these numbers in powers of ten.
I ended up choosing to use the one significant
figure column, because it was the most comfortable one to
use for me. The powers of ten made the range of categories
so broad that I really didn't feel like I got a handle on
it. So in all my other evaluations, I used the column of
one significant figure.
This is the risk to individual workers under
normal conditions. This is the one which you see the
highest risk.
The nice thing here is that you can compare this
to real doses that people get in a typical year, because you
would pretty much expect them to use material properly all
the time and get those kinds of doses.
We don't typically see doses of 3,900 or 2,000 rem
in a year. Even for the radiographers, it's not terribly
normal to be that high anymore.
DR. GARRICK: Thirty millirem, right?
MS. ULLRICH: Yes. I'm sorry. What's a factor of
a thousand between friends, right? No. It's a millirem. I
also ranked the systems just to see how they came out and
that has its interesting aspects, as well.
Here, the numbers are simply the ranking from one
to 47, because as you see, we ended up breaking some of
these systems into smaller portions. You had asked earlier
if we could consolidate it down more and what we found is we
were breaking it into smaller pieces.
It jumps out right away that we got a lot of low
numbers here for radiography at field sites. That's overall
a risky activity, but for some of the other systems, you can
see it really jumps around, depending on what risk you're
looking at.
So I didn't see any point in coming down to a
single number of risks for a system because it hides where
you might want to make some regulatory changes.
DR. GARRICK: I think that's excellent. I think
that was a very wise decision.
MS. ULLRICH: Let's see. One of the other
evaluations we did was to look at how the risk of the
systems stacked up against the way we inspect them.
Materials is a little different from reactors in that we
have categories, priority of inspections. Priority one gets
inspected once a year, priority three every three years,
priority five every five years, and they're unannounced
inspections.
I'm not sure I really see a pattern in there. On
the other hand, it's also clear that we have looked at the
consequences in a lot of the systems in determining who
needs a lot of attention. Radiographers, pharmacies, these
people get looked at every year.
DR. APOSTOLAKIS: Would it make sense now to
inspect teletherapy every three years and nuclear pharmacy
once a year, when you have 50 millirem versus 800?
MS. ULLRICH: Well, that's something that needs to
be looked at. It plays into how good of a dose number.
This is only in order by risk to the individual workers.
It's not looking at any of the other risk categories here in
this comparison.
So there may be other things driving it and one of
the other things that I have to say is that the nuclear
medicine people are just up in arms about how high that
number is. It can't possibly be that high and we got to go
back and look at that again, and, in fact, that may be what
we need to do.
DR. APOSTOLAKIS: Just like the reactor people.
MS. ULLRICH: Yes. It's interesting to look at.
This is something that we need to check and it may be a
place to use some of this information.
The numbers in parentheses are for broad-scope
programs, which may have multiple of these activities.
Under a broad-scope program, they would get inspected every
year.

What are the overall results? I don't believe
that the risk value alone is sufficient to regulate. There
are some byproduct material systems, like the pool
irradiators, that can produce lethal doses of people get
past the barriers, and so you have to make sure that you've
got regulations in place for those kinds of things.
There may be other things that have to be
considered, as well. But I think the risk value does have
its place.
One of the good things, we did not identify, in
the consequences, in those doses, anything unexpected,
anything that we didn't have regulations in place to handle
already.
Lots of general trends, and I think you've already
talked about some of these, that the risk is to the worker,
the public risks are much lower, the accident risks are much
lower. So I don't think we need to go over that in a lot of
detail.
To address that issue of comparing the risk value
to the inspection priority, I probably graphed that three or
four different ways just for the worker risk and really
didn't see a particular pattern. But I'm not sure that it's
the fault of either system right now. The inspection
priorities are based on program types, rather than systems.
The systems are different from the program types
that we use in NMSS. It may indicate, where there's big
differences, that some additional study needs to be made to
see why what we think -- why we need to inspect frequently
is either not justified by the risk value or may need to be
changed.
And the most important thing, and this comes up
with the strontium-90-I applicator, which came into the
bottom of the risk list in every category, just about, the
risk assessment, as we said earlier, didn't include risk to
patients. The strontium-90 applicators really don't have
much harm to workers or people, but there have been some
whopping doses to patients when they were misused or, in one
case, there was a series of misadministrations because they
had the calibration incorrect and the decay curve incorrect
for the use of that device, and that's something for the
Part 35 people to think about, I guess.
Systems with low risk values we can probably look
at to consider for reduction in regulatory burden. I think
these other points are discussed already.
I think it's real important and I'm kind of glad
to hear some of the favorable comments on this report,
because the materials community is picking it apart, for the
ones who do see it.
It's a first attempt to do this. As far as we
could tell, we couldn't find anything of this scope before.
There is certainly some risk assessment done of some
individual material systems. I think there's a PRA for the
gamma knife that was done.
But this scope is a new thing. I think it's got a
good solid basis. It could be extended, if we want to
extend it. It could be used for new systems, if we need to
use it for new systems. It's a consistent way of comparing
the different activities.
So I was really pleased with the NUREG and the
risk database that we received.
Where do we go from here? I think some of the
information from the NUREG, the risk database, the risk
review report, the matrix summary can be used in developing
the safety goals for the NMSS activities. It may be some
resource information to help decide what pilot activities
would be selected, what systems, what kind of byproduct
material activities do we want to look at for more rigorous
risk assessments.
It can be reference information to risk-inform
changes we might need to make in regulations, current
guidance, new rule-making. I believe we've already got a
commitment for the licensing and inspection guidance
document, the NUREG-1556 series. Those start under revision
this year and those teams should be using this information
as a reference to make those revisions.
And I already talked about how I think that risk
database is a useful tool.
So that's what I have for you today. Are there
any other questions at this point?
DR. GARRICK: I'm sure there are. What do you see
as the next move?
MS. ULLRICH: Well, we're always working on
something and the NUREG-1556, I know those revisions are
starting, so I would certainly like to see this involved
with them, and I would personally hope that this information
is able to be used by the folks working on the SECY-99-100
activities.
DR. GARRICK: Have you been tracking at all the
changes that have been made on the reactor side in NRC
oversight and the way the maintenance rule and the IPE work
has influenced the overhaul of NRC oversight for reactor
inspection?
MS. ULLRICH: I would say that I've seen some of
the trickle-down effect from that.
DR. GARRICK: Well, I see a similar opportunity
here. You've touched on it, with trying to matrix the
results with the inspection frequency and duration, I guess.
But I would think this would be an important starting point
for really examining the efficiency and effectiveness of
inspection. Meanwhile, this analysis would also come under
some increased examination and criticism and that would be
constructive, as well.
So I hope that there is some consideration given
to that.
Hornberger? George? We can just encourage you to
keep up the good work. There is no question that in the
details, you can find problems with the analysis, but from a
top-down perspective, it's a giant step forward in
understanding what is going on in the byproduct arena. If
we could do something similarly for the other major
categories of the materials side, and there is movement in
that direction, then I think we would begin to see a risk
perspective of the entire materials side of the business.
The performance assessments are certainly doing
that as far as the repository issue is concerned. The dry
storage is doing some of that as far as fuel storage is
concerned. Then, of course, we heard about fuel fabrication
facilities and fuel cycle facilities.
So it does appear that there is movement and I
guess the only anxiety that some of us have is we would like
to see more commonality, if you wish, of the methods,
because there does seem to be --
DR. APOSTOLAKIS: And terminology.
DR. GARRICK: Yes, and terminology. There does
seem to be a determination on the part of each of these four
or five groups to at least have a certain amount of tools
that are unique to that particular section, and I'm not sure
that's necessary. But the progress that's been made is
still very encouraging.
Any questions from staff? Comments? Thanks,
Betsy. That was very helpful.
Well, what I think we ought to do now is spend a
little time asking what we ought to do with what we've heard
today. I suppose that to be orderly about it, we ought to
just go to the top of the agenda and work our way through.
DR. APOSTOLAKIS: I propose we don't write a
letter on the opening remarks.
DR. GARRICK: I'm glad to hear that. All right.
The first presentation from Virgilio was an overview, risk-
informing NMSS activities. That kind of had a lot of pieces
and parts that maybe we discuss individually.
But what are some of the thoughts of the committee
about what we heard this morning? The committee is only
three-fourths here.
DR. APOSTOLAKIS: I think a general message that
things are happening in various activities and that's good,
but there is a need for, as you just said, for coordination,
perhaps, common terminology, methods and so on. I think
that's a general conclusion that deserves to be documented
somewhere.
There's certainly a lot of work that's going on.
The only one -- if we decide to write a letter that gives an
overview of everything we heard, I would limit it to a short
letter.
Now, the special nuclear materials, I think,
deserves a separate meeting with all details on the ISA and
so on. Maybe we can just put that in this letter. And I
would propose that this become an ACNW letter with enhanced
membership, as we agreed earlier. That would take forever.
The special nuclear materials is of concern to me
because they are sending the rule up next week and clearly
we don't have time to have another meeting and everything.
So I was wondering whether there was a mechanism
alerting the Commission to the fact that maybe more detailed
comments would be forthcoming.
DR. GARRICK: One of the things we've already
observed, it was kind of interesting, that's come out of
these joint committee meetings, is that the energies of the
advisory committees have been, for the most part, consumed
in two areas, reactors and high level waste repositories.
And in the meantime, there's a lot of other
activities going on and it doesn't seem that they have had
the same kind of review and advice on the risk-informed
movement that these two extremes --
DR. APOSTOLAKIS: And I would put that also in the
general comments.
DR. GARRICK: Right, right. So that may make some
suggestions about the planning and the activities of the
committees.
Have you got anything to say about that, John?
MR. RANDALL: Yes. One of the things we discussed
at the last ACNW meeting was the division of work in certain
areas, like decommissioning.
DR. GARRICK: Right.
MR. RANDALL: And there are some other areas, like
Part 70, 71, 72, which were originally included in an MOU.
There is a draft MOU between the ACNW and the EDO, the ACRS
and the EDO, and it lays out areas of coverage for
particular committees.
But there is some overlap and there's some overlap
in Part 70 and we need to handle those, I think, on a case-
by-case basis.
DR. APOSTOLAKIS: That's a different issue. What
we're saying here is that there were some activities that
were not reviewed by --
MR. RANDALL: I know.
DR. GARRICK: Yes.
MR. RANDALL: There's some history to that, and I
don't want to go into all that right now.
DR. GARRICK: Yes. Maybe it was by design, but
anyway. We have some real --
DR. APOSTOLAKIS: We're looking for more work.
DR. GARRICK: -- catching up to do.
MR. RANDALL: There are some activities which are
picking up some areas in NMSS and fuel fabrication
facilities, there's talk about handling an application for a
Mox facility at the same time. NRR will be handling the
licensing and utilization of that material. So there will
be a division of responsibilities, which are already
outlined in this MOU, to look at some of these things. Of
course, they're unbudgeted, so that's a problem I have to
deal with.
Now, the sub-issue you raised if you feel -- if
you have concerns about the staff going forward with this
Part 70 rulemaking activity, I think it's something that we
need to let the staff know either through the EDO or through
the Commission. Usually, these things will go up to the EDO
and then at some point get to the Commission, and the
Commission may not act very quickly on this package.
But we certainly can let the Commission know that
the committee is interested in providing some comments. But
I think the staff would probably like to get a heads-up on
those types of comments in case they want to make any
changes in the document, they have an opportunity to do
that.
DR. APOSTOLAKIS: I think we should have another
meeting just on the special nuclear materials.
MR. RANDALL: Marty, do you have a schedule for
the Commission? Is it on a tracking system?
MR. VIRGILIO: Yes. The paper is going up to the
Commission, as Ted said, within the next week or so. It's
due up to the EDO, I believe, on Monday and then the EDO
gets a couple of days review and then it's due up to the
Commission.
The Commission meeting I think has been scheduled
for the week of June 20, somewhere right around there. It's
up to them how long it takes to decide on moving forward.
One thing that we might want to consider is can
you separate the concerns, the rule and the standard review
plan, and the two categories. One way to proceed, and I
think the rule is written at a fairly high level and you
might find that that's an acceptable approach, I believe it
is, listening to the concerns that were raised today, and
allow us to continue to work together on the standard review
plan through working through examples.
That's an approach that I think would be a good
approach. If it works for you, you would have to look at
the rule and make sure you see the rule the way I do, in
light of the issues that we've discussed today.
DR. GARRICK: That's a good point.
DR. APOSTOLAKIS: In any case, I don't think this
committee -- do we need the reporter?
MR. VIRGILIO: I don't think so, no.
DR. GARRICK: No.
[Whereupon, at 3:45 p.m., the meeting was
concluded.]

Page Last Reviewed/Updated Tuesday, July 12, 2016