Advanced Reactors (Workshop on Regulatory Challenges for Future Nuclear Power Plants) - June 5, 2001
Official Transcript of Proceedings
NUCLEAR REGULATORY COMMISSION
Title: Advisory Committee on Reactor Safeguards
Subcommittee on Advanced Reactors
Docket Number: (not applicable)
Location: Rockville, Maryland
Date: Tuesday, June 5, 2001
Work Order No.: NRC-244 Pages 341-705
NEAL R. GROSS AND CO., INC.
Court Reporters and Transcribers
1323 Rhode Island Avenue, N.W.
Washington, D.C. 20005
UNITED STATES OF AMERICA
NUCLEAR REGULATORY COMMISSION
+ + + + +
ADVISORY COMMITTEE ON REACTOR SAFEGUARDS
+ + + + +
SUBCOMMITTEE ON ADVANCED REACTORS
+ + + + +
JUNE 5, 2001
+ + + + +
+ + + + +
The Subcommittee met at the Auditorium,
Nuclear Regulatory Commission, Two White Flint North,
11545 Rockville Pike, Rockville, Maryland, at 8:30
a.m., Thomas S. Kress, Chairman, presiding.
COMMITTEE MEMBERS PRESENT:
THOMAS S. KRESS, Subcommittee Chairman
GEORGE APOSTOLAKIS, ACRS Chairman
MARIO V. BONACA, ACRS Member
F. PETER FORD, ACRS Member
GRAHAM M. LEITCH, ACRS Member
DANA A. POWERS, ACRS Member
WILLIAM J. SHACK, ACRS Member
COMMITTEE MEMBERS PRESENT (Continued):
JOHN D. SIEBER, ACRS Member
ROBERT E. UHRIG, ACRS Member
GRAHAM B. WALLIS, ACRS Member
B. JOHN GARRICK, ACNW Chairman
Introduction, Chairman Thomas Kress . . . . . . 340
Presentation by Ron Simard . . . . . . . . . . . 346
Presentation of Dr. Neil Todreas . . . . . . . . 368
Presentation by Dr. Andrew Kadak . . . . . . . . 422
Presentation of George Davis . . . . . . . . . . 469
Presentation of Dr. Michael Golay . . . . . . . 480
Presentation of Dr. Charles Forsberg . . . . . . 533
Presentation of Adrian Heymer . . . . . . . . . 580
Commission Discussion . . . . . . . . . . . . . 627
CHAIRMAN KRESS: Will the meeting please
come to order?
I have to read this mandatory statement.
This is the second day of the meeting of the ACRS
Subcommittee on Advanced Reactors.
I'm Thomas Kress, Chairman of the
Subcommittee members in attendance are
ACRS Chairman George Apostolakis. That's him right
DR. APOSTOLAKIS: On time, as usual.
CHAIRMAN KRESS: On time and under budget.
Mario Bonaca. I almost missed that one.
And Graham Wallis.
Also attending is the Honorable ACNW
Chairman John Garrick.
The purpose of this meeting is to continue
our discussions of the regulatory challenges for
future nuclear power plants. The Subcommittee will
gather information, analyze relevant issues and facts,
and formulate proposed positions and actions as
appropriate for deliberation by the full committee.
Michael T. Markley is the cognizant ACRS
Staff Engineer for this meeting.
The rules for participation in today's
meeting have been announced as part of the notice of
this meeting previously published in the Federal
Register on May 10th, 2001.
A transcript of the meeting is being kept
and will be made available as stated in the Federal
It is requested that speakers first
identify themselves and speak with sufficient clarity
and volume so they can be heard. If the people from
the audience wish to make comments, ask questions, and
so forth, please use these microphones on either side
and also identify yourself and speak with sufficient
We have received on written comments or
request for time to make oral statements from members
of the public regarding today's meeting.
The morning session up until lunchtime
will be here in this auditorium. The afternoon
session, we lose this auditorium, and we have to move.
The afternoon session will be in the ACRS Conference
Room, T2B-3 on the second floor. I think everybody
knows where that is.
I don't have any additional comments. Do
any of the members, co-chair have any comments?
CHAIRMAN KRESS: Seeing none, we will now
proceed with the meeting and call on Ron Simard of NEI
to start us off this morning.
MR. SIMARD: Thank you.
Dr. Kress and I were just reminiscing.
When we first met each other 30 years ago, he was
working on Generation IV concepts down at Oak Ridge.
This is probably not the most interesting
title for this talk. Sometimes I've taken to giving
this talk and calling it "The Future Isn't What It
Used to Be," because -- Jenny, would you go to the
Just a reminder as to what's changed, and
today let's try to understand why it's changed and
changing so rapidly, and then I'll try to tie that
back to what it means in terms of challenges to the
NRC in being able to respond to those changes.
But just to summarize what's different
about out view of the future now is it's clear that
we'll need more electricity. This has been coming for
a while as demand has grown, as we've eaten into our
reserve margins. We've seen it in the annual
projections by DOE, the Energy Information
Administration, and now we have the National Energy
Policy out, which makes it pretty clear.
And the problem we have with that is that
we are looking at -- even at the lower end of DOE's
estimates, we're looking at increasing our generating
capacity by almost 50 percent. Fifty percent of a big
number is a very big number, and it's not going to be
possible to meet it entirely with fossil fuels,
whether it's natural gas or coal.
It's becoming increasingly clear that
there are long-term concerns about the price of the
fuel, as well as the physical inability to add that
many more megawatts solely of fossil fired generation
without violating clean air constraints.
And, on the other hand, we're seeing an
increased prospects for nuclear energy partly because
their economics are being perceived as potentially
better in the future and partly because with
restructuring in the industry and consolidation, we're
moving toward a situation where a number of large
generating companies, a small number, are increasingly
moving towards operating the majority of our plants.
Now, I think that this is partly
contributing to the increase we're seeing in the
performance of the plants, this consolidation of
expertise, but it also means looking forward that
these folks have the capital to consider adding more
nuclear plants to the fleet.
We're also seeing a significant change in
public support and certainly political support. I
think Thursday of this week, for example, you'll see
Senator Bingaman's bill introduced, which will help
expand the nuclear work force not only for the
industry, but for the NRC, the full range of the work
force, and the public support has completely reversed
itself even in California where now 60 percent of
Californians tell the field poll -- this is not an NEI
sponsored survey. This is an independent poll --
that more nuclear energy is going to needed.
And finally, and this is what we're here
to talk about today, that last bullet, the potential
is there for increased certainty in the licensing
process, and this is important because it's a new
business environment, and we have to be able to have
certainty with respect to what it's going to take to
bring these new plants to market now in a restructured
Remember that 60 percent of our nuclear
plants today, 60 out of 103 units, are operating in
states where electricity restructuring has occurred.
So there is a fair amount of effort underway, which
I'll try to summarize for you, to prepare for what we
know are near term business decisions.
We know that several companies are
beginning today to make their business plans and their
decisions about whether to add more nuclear to their
fleet, and, Jenny, let's go to the next slide. I
think the next slide might be even better to show you
the scope of activities underway.
You have a copy of this in your handouts,
and what it does is it tries to tie together the
activities I just showed you on that previous slide
and show you how they all come together in an
Up at the top of the slide there, we need
to change the very top of that slide. The very top
box refers to a seminal document that we've been
working from for the last few years. It's a document
that sets the direction for nuclear energy going
forward. There's a new document. As of last month we
have something called "Vision 2020," which I'll talk
about a little bit toward the end here, but what I'd
like to show you here on this slide is that from that
"Vision 2020," or from that statement, which by the
way has been bought into by the NEI board of
directors, that means the chief executives of all the
generating companies and a fair mix of the other
companies across the industry that belong to NEI.
At that level of industry leadership they
have bought into this, and in fact, what you'll see is
that the NEI business plan, our whole plan for next
year and our budget, will, in fact, mirror this
"Vision 2020." It will conform with the objectives
that we're going to be talking about today.
And under that we have a plan, and this
plan assigns work in four areas, and the intent of
this work is to take on as many of the open issues as
we can in the next couple of years roughly and provide
that certainty that the executives are going to need
in their business decisions.
I might just point out on the extreme
right-hand side, I think one of the most challenging
things for us is the infrastructure, and I'm talking
here about not only the people, but also the
manufacturing capabilities, the equipment suppliers,
the engineering services.
We had a kickoff meeting of a task force.
It's the second one in from the right, the work force
issues task force, at NEI yesterday, which has
representatives from the generating companies, the
labor unions, the contractors who supply contract
personnel to our plants, NRC and DOE, and the purpose
of that is to identify the manpower needs for the
entire industry, all aspects of running this operation
in the future, and then to identify where the gaps
are, and finally to lay out actions, how we're going
to fill those gaps.
Now, going back to the licensing area,
that box in the middle, you're going to hear about
that later today, the new plant regulatory framework.
That's the subject of a separate presentation this
Let's focus on the other boxes over there.
Jenny, would you please? Let's go to the next slide.
And let's talk about licensing, and in
three areas in particular. We're talking about the
licensing needs in the very near term with respect to
working out the Part 52 implementation details. Also,
with respect to not only assuring the safety, but how
other types of NRC regulations will apply to these new
types of designs, the kind of designs you heard about
And finally, reflecting the fact that the
next group of plants that's going to be brought to
market may not be brought to market by regulated
utilities in a cost and service environment. Rather,
they will be merchant nuclear power plants competing
on their own merits. They're going to sell all or
part of their electricity to the market, and they're
going to be run by some new approach to the ownership
and risk sharing in these projects.
So let's talk about those three areas.
With respect to Part 52, let's go to the next slide,
Jenny. Maybe it's even better to look at this in a
Compare the top and bottom here. What we
have on the bottom is an efficient new approach to
licensing future plants, and what's relevant to our
theme today, talking about the uncertainties in cost
and schedule, is the fact that this framework holds
the promise for being able to bring these plants to
market with a certainty we've never had before.
On the lower left-hand side, with design
certification, which the NRC has now certified three
advanced designs; with design certification, we also
have this concept of ITAAC, inspections, tests and
analyses, that you can perform and then acceptance
criteria that show that, in fact, you've built the
design that was certified.
That's key because at the end, the bottom
right-hand side here, the focus in post construction
hearings is on whether or not those acceptance
criteria have been met.
So with design certification and the fact
that it's been applied now three times, I think we've
made tremendous progress. What still has to be tested
though are the other two key pieces of Part 52.
On the bottom left, early site permitting.
So one of the things that we currently have underway
are interactions among the industry and between the
industry and NRC and public meetings to work out
exactly how early site permitting will apply.
For example, if we're going to add
additional reactors to sites that already have
reactors up and running, sites that have already been
reviewed by the NRC, the environmental characteristics
are know, for example.
But then the other key and the other
challenge to the NRC now is working out the rest of
that line along the bottom. Once the construction
permit and operating license has been granted and once
the licensee has this extremely effective construction
schedule now, which is capable of bringing these
plants to fuel loading in three years or less, how can
the NRC superimpose its inspection process, and
especially how will they, beginning for the first
time, use this -- verify that, in fact, the ITAAC had
So I think one of the larger challenges
that we're working on today is construction inspection
and ITAAC verification, and that's key. It's key not
only to being able to meet the licensee's construction
schedule, but, again, it's key to that arrow on the
bottom right, to being able to demonstrate to all of
the stakeholders here, the licensee, the NRC, the
public, all of the stakeholders, the key to being able
to demonstrate clearly and unambiguously that the
acceptance criteria have been met.
This is the second area we talked about.
Not only are these designs likely not going to be
brought to market by regulated utilities who are going
to put them in a rate base, get a guaranteed rate of
return, but we're now, as you saw yesterday, talking
about different designs. They are not necessarily
light water reactors anymore.
Some are. We have three advanced light
water reactors that are certified. They're on the
shelf. They're ready to go, but other designs, like
the ones you heard yesterday are modular, for example,
and there's a list of four questions you need to ask.
If it's not a single reactor unit anymore
but a series of modules, well, then how do some of
these NRC regulations apply? For example, you need to
bring clarity to whether or not you can issue one
license for five, six, seven, ten modules at the site.
You also have to clarify the requirements
under Part 140 or Price Anderson.
That third bullet is key. What about the
annual fees, which is on a per reactor basis?
And then finally, the NRC regulations are
quit specific as to the number and qualifications of
people in the control room.
Similarly, in the second bullet, if there
are gas cooled designs, the regulations, for example
5075, currently give estimates for how much money
you'll need to set aside over time to decommission a
PWR or BWR. What about a gas cooled reactor? What
about the generic environmental impacts which are in
Part 51, those two tables that you see there?
And finally, what about the fact that
you're going to have to redefine what are the
appropriate actions to take as part of your emergency
On the next slide, here's the third
example now. Here's yet a third example of a number
of issues that need clarification by NRC, given the
fact that, again, these are not necessarily regulated
utilities applying for a license.
So if it's a merchant plant, for example,
some of the issues that you see currently being
discussed and need near term resolution are the
previous requirements for an anti-trust review, the
requirements for NRC to determine the financial
qualifications, and finally what mechanisms are
appropriate in terms of setting aside that money we
talked about a minute ago for decommissioning of the
So those give you examples, I hope, of the
types of challenges that are before us. Now, let's
just remind ourselves of the urgency. If you believe
DOE projections, and, by the way, you shouldn't
because they've been consistently low. For the past
ten years, their annual projections have been on the
low side, but let's take them at face value.
At their low end of their projections, we
would need to add 400,000 megawatts of new capacity to
the grid by 2020. Now, today 30 percent of our
generating capacity is non-emitting. It's nuclear;
it's hydro and some renewables.
Now, if all you wanted to do was maintain
that 30 percent contribution to avoid getting into
even more problems with clean air, you'd actually have
to add 60,000 megawatts of new nuclear, 60,000
assuming you can get maybe another 10,000 megawatts
out of up rates, 50,000 new.
That's the basis for "Vision 2020."
That's what the industry announced last month at the
Nuclear Energy Assembly. That's what's going to drive
us to the future.
Could you raise it a little bit, Jenny?
Are you able to?
DR. POWERS: There seems to be a body of
opinion that takes issue with this though. I can't
reproduce their arguments, but they seem to think that
maybe we don't need that much electrical energy, and
that we, in fact, can achieve the necessary energy
supplied by conservation.
MR. SIMARD: No question that conservation
and efficiency are important, but it's folly to think
that you're going to conserve your way out of having
to add almost a 50 percent increase.
I mean the gains that we have made in
conservation have been impressive, you know, at times,
and efficiency has really helped quite a bit, but
there's no way that you're going to conserve your way
out of the low end of this projection without
disruptive impacts on the economy.
So, you know, take issue. You don't
believe we need 400,000 megawatts? Okay, fine. Cut
it in half. Let's suppose that we're able to bring
the sort of passion to this that we brought to the
Manhattan Project, and we're able to achieve
unprecedented levels of conservation and efficiency
and shave that in half.
DR. POWERS: You don't look like you're
intimately familiar with the passion of the Manhattan
MR. SIMARD: Well, seriously, I think that
what you find now across -- yes, it's true. There are
still some people who will question that, the need to
have that much electricity and they might even go so
far as to say that we can keep our current demand
steady. I don't know.
But you don't find them having prominent
roles in policy making anymore. What you find among
the policy makers, whether you read the
administration's national energy policy or whether you
look at the Nuclear Caucus in the Senate or the House
Nuclear Issues Working Group, when you look at the
bills that are currently out there from Senator
Dominici, Bingaman, Murkowski, Mr. Gramm, you see a
growing consensus, I think, among the policy makers
that this sort of aggressive action is going to be
I mean this is what we could do. To
maintain that 30 percent, as you work your way up the
bottom here, there's a small yellow band, which
actually it's small on the scale, but 10,000 megawatts
from power upgrades is actually pretty substantial.
And then you see what would have to be
added, some 50,000 megawatts, and again, that's just
to maintain the brackets there. That's just to
maintain the current contribution and to avoid getting
into even more trouble with clean air.
So let me just summarize then over the
next couple of slides. The future isn't what it used
to be because I think the consensus is here now that
the demand will grow, and we used to talk about the
nuclear option. It's not an option anymore. It's an
The business case for new plants is pretty
clear, but we have to have cost and schedules known to
a greater degree of certainty than we ever had before,
which leads us into the challenge for the NRC because,
as you saw a minute ago, the ability to bring this
plant to make depends upon being able to work out
these Part 52 implementation issues in a timely
manner, and having in place efficient and,
Commissioner Diaz's word, "scrutable" processes for
early siting and licensing and construction
And I think what's emerging here from this
day and a half is the challenge for NRC to be able to
respond to this with a whole new focus and discipline
DR. POWERS: One of the persistent
problems that we encounter when new things are brought
to this particular body is the documentation is
incomplete, documentation is not rigorous. Those
kinds of things slow the process substantially.
Is the industry doing anything to try to
address those kinds of questions?
MR. SIMARD: I think the challenge on our
side is to bring in an unprecedented quality of
application. On our side, we need to bring the NRC
the highest quality information and application.
And I think what you're seeing both with
the Westinghouse and PBMR North America International
with NRC now is an effort early on to really clearly
identify exactly what the staff needs are going to be
to be able to do their review.
So I think that's encouraging, but you're
DR. POWERS: For heaven's sake, solve the
momentum equation properly.
MR. SIMARD: You're right. We need to do
better, too, on our side.
CHAIRMAN KRESS: Ron, one of your slides
pointed out some of the regulatory challenges
associated with multiple modules on a given site, how
you deal with that with respect to site permitting and
certain financial issues associated with that. It
seems obvious to me that what you should do is get a
site permit for the maximum number of modules you
expect to put on that and call it one facility.
Is that something your guys are proposing
or is that --
MR. SIMARD: Yeah, and maybe -- in that
area maybe "challenge" is too wrong a word here.
Maybe we're getting carried away by the theme of the
workshop here. Some of these things ought to be
CHAIRMAN KRESS: Yeah, that one looks
pretty clear to me.
MR. SIMARD: But the point is they do
though require either a clarification or a change to
the current NRC implementation requirements. So, no,
I think that's a good point.
Some of these shouldn't be challenges.
They're pretty straightforward.
DR. APOSTOLAKIS: In one of your earlier
slides on new licensing process significantly reduces
project risk where you have the chart, maybe we can go
back to it. They're not numbered, but, the heading is
"new licensing process significantly reduces project
MR. SIMARD: Yeah, it reduces the
perceived business risk on the part of the licensee,
and it certainly provides for earlier and more meaning
parts of --
DR. APOSTOLAKIS: It's the fifth or sixth
MR. SIMARD: Yeah, she's got it now.
DR. APOSTOLAKIS: Oh, yeah, that is the
When you say at the bottom here
"acceptance criteria met," I guess the acceptance
criteria, do we have those now or --
MR. SIMARD: Yes, in the three designs
that have been certified, a key feature and a high
level of detail in those certifications are the ITAAC.
So they're clearly specified. In the ABWR, for
example, the high pressure core flooder system, I
understand there were 31 separate ITAAC that clearly
focus on the performance of a pump, for example.
What inspections or tests will be done on
that pump and what acceptance criteria will be
necessary to show that, in fact, that pump is going to
deliver the amount of water you need at the time you
So in the design certification, a key
feature of them has been these ITAAC. We need to add
a few more that are site specific when the licensee
brings you the application, but --
DR. APOSTOLAKIS: So in terms of Part 52,
which you cited as one of the major challenges, the
implementation of Part 52, and if I look at this
particular chart, where does the implementation of
Part 52 come into the picture? Just the whole
MR. SIMARD: Well, there are actually
three pieces to Part 52. The bottom left there,
there's one that outlines design certification. Then
there's one that outlines early site permitting, and
then in the middle there on the bottom, there's one
that talks about the conditions on granting a
construction permit and operating license.
And then finally it also covers at the end
of construction and prior to start-up the basis for
the NRC determination that the plant is ready to go.
DR. APOSTOLAKIS: Well, yesterday there
was a lot of discussion of using risk information in
all of this. So if I were to choose one of the
designs that have not been certified yet, then the
potential for using risk information is on the left
where it says "design certification"?
MR. SIMARD: Oh, no, certainly. But what
about all the way across?
DR. APOSTOLAKIS: All the way.
MR. SIMARD: Yeah, when the NRC has to
dust off its construction inspection and program and
apply it now to these new designs, this new
environment, but with the knowledge that we've gained
over, you know, the past 30 or 40 years, it certainly
would make sense to focus on the aspects of
construction and the completion of SSCs that are most
important to safety, and I think in our interactions
with interactions with NRC on this subject, which are
about to begin this month, we'll certainly be looking
at it from our point of view.
DR. APOSTOLAKIS: So we'll hear more about
this this afternoon, I understand, right?
MR. SIMARD: I don't know that you will.
You know, from Adrian Heymer you're certainly hear
about the proposal that we have in mind for the
overall regulatory framework, but in terms of the
specifics of how NRC might modify the inspection
DR. APOSTOLAKIS: No, no, no, no.
MR. SIMARD: No, that's still something
that needs to be worked out.
DR. APOSTOLAKIS: Sure.
CHAIRMAN KRESS: Any other questions from
the audience or other members?
DR. APOSTOLAKIS: There is one here.
CHAIRMAN KRESS: Ah, good.
MR. ALLEY: Neil Alley.
In your projections for energy demands
looking forward, what assumptions did you make about
plan life extension?
MR. SIMARD: You know, i'm not sure. If
you're asking specifically about "Vision 2020" and how
we're going to meet the need for 60,000 new megawatts,
I think that we assumed almost all the plants are
going to go in for license renewal. I can't tell you
for sure though whether it was 100 percent or, you
know, maybe we drop back a bit, but certainly the
feeling in the industry is that all or almost all of
the plants are candidates for renewal rate.
But also remember -- I'm sorry. The real
answer to your question is this is 2020. All right?
So you wouldn't see a significant number of today's
plants reaching the end of their life anyway before
DR. POWERS: Yeah, there are a bunch of
them. Without license renewal, there are a bunch of
them that are out by 2014, some by 2007. Yeah,
license renewal is very important.
MR. SIMARD: But anyway, the answer is at
this point it looks like all, if not -- it looks like
all or almost all of the plants are candidates.
DR. POWERS: About 80 percent.
MR. QUINN: Dr. Kress, it's Ted Quinn.
Ron, good morning. The reason for success
in the license renewal process to a large extent was
the project management role that was put in place with
a lot of work by NEI with a lot of work by the NRC,
and a suite of documents that became part of the
process, the GALL report, the NEI guideline.
Have you considered working with NRC on a
similar type of suite of documents to help us make
this a more stable framework?
MR. SIMARD: Yeah, I think you're right,
Ted. That's been a good model in the past. By
bringing to bear the range of industry resources and
expertise on an area and combining that with the NRC,
I think we've wound up with a better quality product
in the end and improved the efficiency of the process.
So building on our success with license
renewal, maintenance rule or other things like that,
yeah, it's our intent to put a lot of thought from our
side into how -- for example, the format of an early
site permit application, and that's something we
actually have underway, or with respect to
construction inspection at ITAAC verification, it's
our intent to bring together the folks who still have
construction experience in the industry, if we can
find them, and again, drawing upon their expertise and
our knowledge of how Part 52 -- the basic principles
of Part 52.
Again, it would be our intent in cases
like that to bring in a document and ask the NRC for,
you know, its review and reactions and use that as the
framework for these productive discussions.
CHAIRMAN KRESS: Well, thank you very
much, Ron, for this very informative and interesting
Then we will turn to the next item, safety
goals for future nuclear power plants, and I'm
certainly looking forward to hearing this one.
By the way, Neil, I know that you don't
need any introduction, but the fact is I don't have
any introductory material so you have to introduce
yourself at this particular meeting.
DR. POWERS: I'm dying to know what a
DR. TODREAS: KEPCO in the title speaks
basically to the success of the Asian countries in
developing nuclear power and up till now the lack of
success in the U.S. So the Korea Electric Power
Company gave a chair to MIT in nuclear engineering,
which I hold, and the Tokyo Electric Power Company
gave a chair to nuclear engineering that Mughid
Khazzami (phonetic) holds, and we're still waiting
perhaps nationally for one of the U.S. utilities to
DR. TODREAS: Okay. What I'm going to do
is stand here. My intention is to address you guys
relative to this question of future nuclear plants and
also bring the audience up to speed in terms of our
Yesterday, the DOE folks were here, and
they talked about the program, and it's called really
a Generation IV reactor development program, and it
covers the near term, which is zero to ten years;
deployment, in that period; and then from 2010 to 2030
the development of what's called Generation IV plants.
So the word "future" here means a lot to
different people. What Ron just spoke about in terms
of my focus was the near term deployment, mainly zero
to ten years. So you have to switch horses now in
terms of the safety goals that I'm talking about
relative to future plants are aimed at the 2010 to
You can take these goals, focus them back
and ask what about the near term deployment plants,
but in a sense that isn't fair because you know some
of them are already certified. If they're not
certified like the ESBWR, they've been under
development for years, and so they've been aimed
There are also nuclear power plants in
terms of near term deployment, and you'll see that
although I was given this title, our goals are on
nuclear energy systems, the difference. Nuclear
energy systems brings in the whole fuel cycle. In
terms of our activities, we put the whole fuel cycle
on the spectrum.
So with those introductory remarks, I just
want to conclude by saying John Garrick is on the
group with Saul and I, Saul Levy and I leading it, and
we have five, six rather, other people on the review
committee overseeing the DOE activity and offering
comments, and John is a valued member of that
So if I could start, having talked to the
people in front of me before at times, I thought I'd
start off and tell you how not to construe this talk
or how to misconstrue it to try to get you on the
So first, it's the talk and then the
goals, and then we'll get into it.
So the way you follow this slide is four
points here, is really what I'm talking about down
below. So I'm not talking about the NRC safety goals.
That's the first thing that probably jumps to your
mind when I say safety goals.
We're generating what we call technology
goals. These are goals to drive new reactor systems
DR. WALLIS: Are you going to mention the
DR. TODREAS: Risk? Maybe at the very
end, but actually Graham, that is one of the themes.
What I want to do or what we want to promote through
this program is technological innovation and
development, and we want to structure things so that
we can promote that and not clamp down too early.
Of course, risk has to be mentioned from
We are not suggesting regulatory
requirements for future plants. These goals are
formulated to stimulate innovation, as I've already
said, and the goals, of course, as you're going to
see, are general, and there's a group that's following
up to put specific metrics on each of the goals so
that we can use those.
We also use those to sort out concepts
from among -- we've gotten effectively almost 100
concepts or pieces of concepts submitted into the
program, and these have to be sorted out, selected,
and areas of R&D picked out either generic along a --
if a set of concepts come together in a technological
direction, will pick out the R&D that's relevant to
this set, and push ahead.
And so we're going to need to make some
selection, and the selection will be based on metrics
which are derived from the goals which are now being
worked on. That's what the word "metric" means here.
I mention the point we're not talking
solely about power reactors. We're talking about fuel
cycles, and the power reactor is part of this. We
started this before the national energy policy was
announced. It's interesting that there's some
consistency there, but it wasn't a grand plot.
And then finally, I'm not talking about
goals for near term deployment plants. I mention that
point. We're talking in the range 2011, 2030 or 2010,
We go to the next slide.
I've got a few points to mention on how
not to misconstrue the goals. One way to misconstrue
them is to assume that future plants must meet every
goal or must even exceed every goal, and what you're
going to see is these goals are fairly encompassing.
Just immediately, to put some meat on those bones,
we've got issues of fuel utilization,
nonproliferation, and waste, and through the fuel
cycle there's obviously got to be a tradeoff among
those areas, and the tradeoff -- there's multiple
tradeoff solutions available and some of them will
favor one of those factors. Some of them will favor
I'm almost convinced that you won't be
able to come up with some scheme that will uniformly
meet and exceed all of these goals. So --
DR. POWERS: I'm glad that you mentioned
the word "tradeoff." One of the questions that comes
to mind, especially after the previous speaker
portrayed something of a crisis appearing, I wonder if
in looking at these goals and looking at new systems
that you compare the more modern or the existing
plants against him to see if we really need all new
concepts, and the 94 new concepts that were portrayed
to us yesterday or, in fact, how well do the existing
plants meet these various goals that you've laid out?
DR. TODREAS: The answer to that is on the
metrics that we're going to develop to assess these
new concepts. We've picked a standard, and the
evaluation process will measure these new concepts
against the standard. Is it better, much better, et
cetera, worse, much worse, and the standard we picked
is the advanced LWR with once through fuel cycle.
The rest of your question asked me what's
the answer going to be, and I don't know that yet.
DR. POWERS: I find that a peculiar
standard to pick because we don't have a whole lot of
experience with advanced LWR, or if we do with
existing machines, we have a lot of experience, and
that experience, at least my friends at NEI certainly
provide metrics that suggest that experience is
outstanding right now.
DR. TODREAS: And is the implication that
the advanced LWRs will be less --
DR. POWERS: I have no idea what they are.
DR. TODREAS: -- performers than --
DR. POWERS: I have no idea how they'll
do. I certainly have opinions on a couple of them,
but I have no proof. Whereas with some of the
existing machines, I know exactly what they're doing.
I've got data I can point to.
DR. TODREAS: I can see thinking about
that, but if we're going to develop advanced systems,
I would say from the vendor community and the
development community, we've got ABWR experience to an
extent, and we have some degree of real respect for
what the designs have accomplished in the ALWR.
And I would say as a minimum you'd include
both, but I certainly wouldn't go back just to the
operating reactors as the standard for the future. I
wouldn't ignore the 15 years of ALWR development.
CHAIRMAN KRESS: Well, you probably have
three criteria. You want them to be safe, and you
want them to be economic, and you want them to be
acceptable to the public and other people.
I would say the current place is certainly
safe enough if you compare them to certain safety
standards, but I would guess economics might be a big
driver, especially the capital cost. I'm not sure.
DR. POWERS: The numbers I see suggest
that they're producing power as cheaply as anybody.
CHAIRMAN KRESS: I know. That's because
they've already gotten rid of their capital costs, and
they're just talking about operating costs, but I
would suspect these new designs are much cheaper to
DR. POWERS: Well, I wonder how much it
would cost to build a plant today, a current plant
CHAIRMAN KRESS: Well, that's a good
question, and I'm not sure I know the answer to that.
DR. POWERS: I don't know the answer
CHAIRMAN KRESS: My guess would be the new
designs would be cheaper to build, but then there's
that third attribute, and that's acceptability, and I
suspect newer, safer, inherently -- plant that has
these attributes that we're looking at might be more
acceptable from the standpoint of the public.
DR. POWERS: Yeah, I don't know.
CHAIRMAN KRESS: I don't know.
DR. POWERS: You're giving up 3,000
reactor years of operational experience when you make
those statements, and --
CHAIRMAN KRESS: Well, maybe.
DR. POWERS: -- I don't think we've begun
to discover all of the ways that you can run afoul on
some of these modern control systems.
CHAIRMAN KRESS: Yeah, you have a good
DR. TODREAS: Okay. Well, I think you
guys will have plenty of time to focus on that one
actually when you get your next certification
application as well, but let's say that point's on the
board. We can chew it further later if we desire.
I'll carry on on these goals down at this
point. The desirable outcome from this program and
effectively the goals which are going to drive this
program I believe is a spectrum of designs, each of
which best meet possible future market conditions.
For example, we don't know, although we
think uranium will be cheap in the future, in fact, as
cheap as it's been in the past, but we don't know that
for sure. So it would be nice to have advanced
designs on the table as the output which could respond
in either direction.
If you want to have designs which would
respond in either direction, then these alternate
designs effectively would be aimed at optimizing and
exceeding certain goals in one direction and then
meeting, but exceeding other goals in the other
So you want a spectrum of results, and
therefore, different goals will drive you in these
the next point is some of the goals, in
fact, one presently appears unattainable.
CHAIRMAN KRESS: That one really surprises
DR. TODREAS: Well, why don't we wait for
the full discussion when I get there?
CHAIRMAN KRESS: Okay.
DR. TODREAS: But the point I want to make
is don't jump on it now. We want a goal that will
drive design and innovation. We can't meet it no, but
does that mean we shouldn't write it in?
That's the question. I know you've read
ahead. We'll get to it where we cover S&R3, Safety
and Reliability 3.
And then finally, as I mentioned, the
goals in terms of their specificity purposely have a
little generality to them because we are talking about
reactor systems that we want to bring on in this time
frame, 2010 to 2030, which gives us an opportunity to
innovate. So we don't want to squeeze down too early
DR. WALLIS: And, Neil, we're still not on
the subject of misconstruing goals, are we?
DR. TODREAS: Yeah, I am.
DR. WALLIS: You are? Okay.
DR. TODREAS: Yeah. The point of
misconstruing there is why are they general. They're
general to open the door.
The next point is that one can misconstrue
these goals by assuming that all the safety
considerations are under the title of the grouping
"safety and reliability goals."
To go ahead, we have sustainability goals,
three of those; safety and reliability goals, three of
those; and economic goals, two of those. So a quick
reading would say, hey, let's just look at the safety
and reliability goals for safety implications.
Now, we should be all smarter than that to
realize that future designs are going to involve new
cycles and a broader range of energy products. So
we're going to get into new fuel materials, higher
burn-ups, longer operating cycles, higher temperature
operation, and all those design directions bring in
safety considerations as part of it. They have all
been reduced specifically to risk criteria, but
there's tremendous safety opportunities and safety
factors that one must consider as part of the
sustainability and, in fact, the direction that the
economic goals will drive us to. That's the point of
Now, with that, we can go to the next one
and start on the goals. the logic in framing these
goals cycled many times because obviously there was a
large community involved in deriving these goals.
What we finally felt was it would be
desirable to group them and then have these
subcategories, and the first grouping that we picked
was sustainability with the idea that if nuclear power
was going to stand head and shoulders strong relative
to alternate energy generation approaches into the
future. we had to address and label part of the goals
through the sustainability label and really place or
position nuclear power and the product that came out
of this product as a sustainable product.
You can get into arguments on this in the
sense that sustainability if you go through the formal
definition kind of projects it out without any time
bound, and yet nuclear power in terms of fuel that
we're going to use has a long time horizon, but it's
There we didn't basically accept that
point and, therefore, say nuclear power will no be
sustainable, but we really took the bit and through
the first goal effectively positioned nuclear power
product as a sustainable product.
This, I've given you the words, but the
words in red are the words that we got into the most
discussion about because this went through the NERAC
process, and NERAC is -- let me call it a balanced
committee. So there's viewpoints on all sides of the
drivability and the effectiveness of nuclear power.
If you've been in the business a longer
time and you're a nuclear engineer, when you think of
fuel utilization, the word "high fuel utilization"
jumps to your mind. This word that's here, which is
"effective," is a long, negotiated word. It doesn't
say we've got to go toward high fuel utilization
because if you say you've got to go toward high fuel
utilization, you immediately prejudice the outcome, so
it is viewed, and with some justification. You
prejudice it toward the fact that you definitely need
a breeder, and also that fuel economics are going to
come and constrain you in this 20-year time frame.
And that definitely is a view that
definitely is not held throughout the review
structure. So the word "effective" here means that
you balance fuel cycle economics with environmental
considerations and with nonproliferation
So effective fuel utilization implies that
a tradeoff is going to be made between those factors
because when I said fuel cycle economics, if, in fact,
we have uranium constraints, that will drive up the
price, and that will be reflected in fuel cycle
In terms of Sustainability 2, that issue
comes down to saying something about nuclear waste.
We have got two key words here, minimize and manager.
Manager is not controversial, but the word "minimize
nuclear waste" was very controversial, and it was
controversial in the sense that the other viewpoint
was that minimization isn't really what you're after.
What you're after is even beyond toxicity. It's
ultimately burden to public health and safety, and
there's a lot of different factors and a lot of
different streams that finally get you down to that.
We effectively pick that up through
reduced long-term stewardship burden, but we -- and
now I'm talking about our review committee and the DOE
whole project -- we still felt that there's great
advantage going into the future with systems that
minimized the waste generation because if you minimize
the waste generation, you at least tend to reduce
pressure which comes from the pile-up of large amounts
of waste, and the question of what do you do after
And I was going to say hopefully. What do
you do hopefully after Yucca Mountain, with the
"hopefully" being hoping Yucca Mountain gets moving?
On the third one on Sustainability 3, this
has to do with nonproliferation, and there was a
special group that was run by John Taylor called TOPS
on nonproliferation where that issue was debated, and
they effectively came up with these words: very
unattractive and least desirable group.
And that comes from the view that we're
going to have intrinsic and extrinsic barriers to
proliferation. Hopefully they're mutually supportive
in that you can do something intrinsically that may
have a positive effect on external barriers and vice
versa, but the view is that there's no silver bullet
here. We're not going to come up with a fuel cycle
that from an intrinsic point of view puts the
nonproliferation issue to bed.
And therefore, we're going to come up with
schemes that are very unattractive and are the least
desirable group. That's how those words came about
and why they're important.
We go to the next slide. Here we have the
safety and reliability slides. They're set up in the
logic of maintaining excellence in safety and
reliability. Here we're really focusing on accident
initiators, reliability of operation of plant.
Actually it stimulates a point relative to
what Dana Powers mentioned. We do want to capture all
the lessons, all of the positive lessons from
operating plants and put those into these Generation
4 systems relative to their ability to operate with
safety and reliability.
This goal, when you're working on advanced
plants, you really at least in the conceptual stage,
you really always focus down on the second two goals,
and what we wanted to do was actually put something
right up front that reminded all of the designers, all
of the conceptual innovators that fundamentally the
plant operating through steady state and through
transience had to capture this base.
Now, when we come to the second goal, then
we get into the traditional language, dialogue that
we're all used to about low likelihood and degree of
core damage. So we, of course, want to emphasize
DR. POWERS: One of the ways of assuring
that you have minimal --
DR. TODREAS: What was the verb you used?
One of the ways of?
DR. POWERS: Assuring --
DR. TODREAS: Assuring.
DR. POWERS: -- that you have minimal core
damage would be to release all of the fission products
so that you have no decay heat. Release them as
they're generated. That would meet this goal.
DR. TODREAS: You would have to release
them and sequester them because we're talking about
systems, but along the line you're talking about, we
get them out of reactor core system where we might
have less control into a system that wasn't operating.
Not a bad --
DR. POWERS: My point really is that I
think this goal is perplexing in the context of the
kinds of designs that people are coming up with where
classical core damage doesn't really occur, but you
still worry about fission product releases.
And why not cast the goal in terms of
release of radioactivity?
DR. TODREAS: Oh. It's -- maybe, maybe.
That effectively leads to number three, where we're
talking about the need for off-site emergency
response, various ways to do that and fission
Fission products actually could be the
whole story down here, and you might think about
writing it that way. I'm not sure, Dana, whether just
off the top, whether writing it that way would capture
the end product or not, but it's simulating --
DR. WALLIS: I think that while you're
being innovative, you should not use -- you seem to be
here really talking about core damage frequency, and
that just may get you in a box, and I think to be
innovative, to follow up with Dana, you really ought
to get away from these terms of the past and be more
CHAIRMAN KRESS: And after all, I think it
is fission products we're worried about.
DR. TODREAS: I think that's a reasonable
point. If I've got you guys or if you've got me
saying that we ought to get away from terms of the
past which will lock us into certain design directions
and means of dialogue, that is really my whole
And if you're offering me a suggestion
that says, hey, what you wrote doesn't go that way;
you should go a different way, then I'd perfectly
DR. GARRICK: I think we have to be a
little careful to unduly focus on fission products
because for many of the most important scenarios it is
not the fission products that's driving the long-term
performance of Yucca Mountain. It's mainly -- well,
technetium and Iodine 129 certainly are in there, but
depending on the scenario and depending on how you
look at it, Neptunium 237 is the principal driver.
And also, in most low level waste
situations, you find that much to our surprise most of
the low level waste is uranium contaminated. So,
again, the fission products are not driving the long-
term stewardship or management of a lot of the low
level waste, but rather it's actinides.
The same thing is true in WIP for
transuranic waste. Again, it's not fission products,
but it's plutonium. So --
DR. POWERS: The distinction between
captured products and fission products I'm not sure I
DR. GARRICK: Well, it sounded like you
were drawing that. It sounded like you were drawing
DR. POWERS: I wouldn't do that. I would
call them radionuclides maybe.
CHAIRMAN KRESS: We put quotes around the
words "fission products" at ACRS. When we say that,
we mean all of those things that you talked about.
DR. GARRICK: Well, then I think we need
to be more precise.
CHAIRMAN KRESS: Yeah, precision would
have helped there.
DR. TODREAS: But that also refers back to
the sustainability goal. It really doesn't obviate
the suggestion relative to S&R 2 here relative to core
damage. I say that because what Garrick's comment
really impacts on is the waste issue, not effectively
the immediate release through core damage. Okay.
CHAIRMAN KRESS: I'm intrigued by that
third bullet. Are you going to talk about it some
DR. TODREAS: Yeah.
CHAIRMAN KRESS: In particular, do you
have some sort of criteria on what it would take to
eliminate this need?
And if so, does that criteria encompass
some sort of measure of defense and depth also?
DR. POWERS: I would go even farther and
say that what more tangible proof of the concern over
the public do you have than an emergency preparedness
zone, and what are you going to replace that tangible
CHAIRMAN KRESS: That's another way to
view it, yeah.
DR. TODREAS: Yeah, but that's how you
guys ought to look at it.
Will you skip to S&R 3? It's the third
viewgraph after this.
CHAIRMAN KRESS: Number nine.
DR. POWERS: Number nine.
DR. TODREAS: Yeah, page number 9.
From the point of view of a regulator or
a group advising a regulator, and we got into this
discussion immediately, the immediate question comes
to mind. Okay. It's find that you guys got this
goal, but what are we going to do about it?
And this goal doesn't say at all that in
the first instance you people need to back off about
planning for emergency response. This is about the
misconstruing right at the beginning.
These are technology goals. These are
goals we want to drive the designers into thinking
CHAIRMAN KRESS: How would you know if you
met that goal? That was my question. What is the
measure that you're going to use to say, "Okay. The
technology we have here meets that goal." Whether or
not it actually comes about or not is another thing.
DR. TODREAS: The measure has got to be
release of I'd say fission products or radioactivity
of a certain amount past the boundary.
DR. POWERS: I can always find a way to
get that many fission products out. There's no
conceivable design; I can't imagine a scenario that
will result in release of excessive amounts of fission
DR. TODREAS: That would prevent it or
that would --
DR. POWERS: Any design you come up with
I can find a mechanism to get the fission products
out; the point that it violates some emergency
CHAIRMAN KRESS: Yeah, there has to be a
frequency involved there is what he's saying partly,
and my question is: is that value of fission products
a value that you would meet, for example, the early
fatality safety goal without evacuation? That's one
DR. TODREAS: That's one possibility.
What I did here is, well, we have written a discussion
under each goal. I worked hard on Paragraph 1.
The debate was effectively you write down
something now that you don't have a way in your own
mind of achieving or do you come short of that and,
you know, put some numerical or put something that
kind of reflects current technology?
So in the interest of intellectual
honesty, we wrote in its demonstration may prove to be
unachievable, and this is what Dana Powers basically
just said. He's saying as he sits on this group, and
I presume and I hope he'll sit on it for a number of
years, all of these designs which come through which
claim that they can meet it, he's going to shoot the
hole in them. Quite possible.
DR. APOSTOLAKIS: Dana would never do
DR. TODREAS: But that is a reason to
write this goal down, because if you're really talking
about future systems and vulnerabilities of future
systems, it's this whole -- and ultimately public
acceptance, it's this whole idea of off-site response
that's a very, very significant issue.
DR. WALLIS: Now, this includes you
started your talk saying you were looking at the whole
fuel cycle. So presumably this includes fuel
fabrication, transportation, any kind of reprocessing.
DR. TODREAS: Yes.
DR. WALLIS: You seem to have focused,
again, on the reactor in this discussion, and --
DR. TODREAS: In the discussion below, not
in the goal above. I'm just scanning it.
DR. WALLIS: Off site radiation then means
in the fuel fabrication facility as well, for
DR. TODREAS: What was the word you --
DR. WALLIS: Well, you're looking at the
whole fuel cycle you said in the beginning of your
DR. TODREAS: yeah.
DR. WALLIS: And now I got the impression
in talking about these goals you were focusing once
again on the reactor itself.
DR. TODREAS: Yeah. It may be true that
in the oral persona that I'm putting across my years
as a reactor designer come through, and I should be
pulling back, being consistent with nuclear systems,
and as I read this discussion here, there's nothing
here that's focused on the reactor. It's general to
all of the facility.
So it's --
DR. WALLIS: Well, it talks about off
site. I mean off site presumably in transportation
includes off the truck or something.
DR. TODREAS: Yeah, okay. Off site, of
course, carries with it, yeah, we have to -- we have
to go through and scrub it. I agree.
CHAIRMAN KRESS: But I would love for
someone to tell me exactly what it takes to meet this
goal. I personally think I know, and I'd like to have
some corroboration of that some time.
DR. TODREAS: Okay.
DR. POWERS: And I'd like to know why
you'd want to.
CHAIRMAN KRESS: Well, that's another
DR. APOSTOLAKIS: I'd like to come back to
the safety and reliability, goal number two.
DR. TODREAS: Could you flip back the
DR. APOSTOLAKIS: Page 6.
DR. TODREAS: Go to page 8. It gives you
DR. APOSTOLAKIS: Yeah. In fact, I was
looking at page 8.
It seems to me that when the discussion a
few minutes earlier brought up the issue of fission
product releases and as a possible candidate for
replacing this, it focused too much on the safety, and
here it says safety and reliability, and if you go to
page 8, it says this goal is vital to achieve
So it seems to me that I can have serious
damage even with the new designs to my investment, and
still I don't release anything. So the words "reactor
core damage," I think, were a little bit provocative
here because yesterday we heard speaker after speaker
saying this is something of the past, and you know,
this core cannot be damaged.
But I'm sure that one can define what we
call plan damage states in PRAs, where you are not
really releasing anything outside anyway, but your
investment has been, you know, severely hurt, and the
NRC is up in arms.
So the challenge will be to define those
states, but I think by taking the words out, "reactor
core damage," and finding some other words, not going
all the way to fission product release, this goal will
serve safety and reliability. You may need a fourth
goal regarding fission product release. I don't know,
but that, again, as you say, these are technology
goals. They are not regulatory goals.
We will definitely have to look at fission
product release. I mean there's no question about it.
DR. POWERS: You think?
DR. TODREAS: Yeah, let me pick up on
that. This is on page 8, if you back into that.
We very much had investment protection on
our mind as well, and in fact, that's why on the
second line I've got that highlighted. Originally, or
through a large part of this dialogue, in that goal we
had the additional statement about preserving the
plant's ability actually to return to power I won't
say promptly, but to return to power over a period of,
let's say, months, with the idea that we wanted to
preserve the investment by having a design that
actually could come back.
So that's what was in the second line.
That one in the discussion, the comments actually came
back as in the third one as to how would you ever do
it. If you got core damage, it's just so much based
on our experience that core damage, even to a minor
degree, is going to really impact negatively the
ability of the plant to return to power.
DR. WALLIS: Well, supposed you have a
core which is fluid. You just flush out the back part
and start again.
DR. TODREAS: Yeah. Well, see, that's the
point. If you get locked back into solid fuel pins,
et cetera, you can't conceive --
DR. WALLIS: But you're being creative.
DR. TODREAS: What?
DR. WALLIS: You're being creative.
You're looking at all kinds of things. There may be
things where you can just flush out the damage and
DR. TODREAS: Well --
DR. APOSTOLAKIS: How about if you
replace, say, generation for nuclear energy systems
will have a very low likelihood and degree of plan
damage, period? To be determined later. At this
point you're high level.
DR. TODREAS: Well, in relation to
Graham's point, we kept the idea here by actually
putting it in the second sentence. The --
DR. WALLIS: The second sentence is
terrible. The possibility is either zero or one, and
you reduce the possibility. I mean, that's crazy.
You're just trying to avoid the word "probability."
How did you ever let anybody use the word
"possibility" in here? That zero or one, isn't it?
DR. TODREAS: Where is "possibility"? Oh,
DR. WALLIS: On three.
DR. TODREAS: The second -- yeah, the
third line, "reduce the possibility."
DR. WALLIS: Well, we shouldn't pick on
words, but I mean, I think --
DR. TODREAS: No, that is fair because
these words in this paragraph get reduced to more
specific items subsequently. So the guidance in this
paragraph is aimed at developing more specific
metrics, and to the degree if that occurs that these
words cloud the ability of the subsequent group to
develop the metrics, it's fair game. So you've made
Follow up. You're shaking your head.
DR. WALLIS: Well, the word "possibility"
DR. TODREAS: Oh, that's what I said.
You've made your point.
DR. WALLIS: All right. Okay. So you
DR. TODREAS: The other point that I
wanted to make down here was there was a lot of
discussion about passive safety features, and this is
written basically to say evaluate them, but there is
a community and a viewpoint that passive safety
features compared to active safety features should be
It seemed to those of us putting these
things together that that was a design tradeoff. It's
not necessarily obvious that the passive safety
features throughout to be preferred, to be preferred
and to push out active features.
That's more of a detail, a trade-off, and
while we wanted to have passive features examined, we
didn't want to push them unduly. That's the
significance of these words at the end.
I haven't followed all of your
deliberations and views on that, but I would presume
it's consistent. If not, I presume I'll hear about
DR. APOSTOLAKIS: I have a comment in the
middle of the paragraph.
DR. TODREAS: Yeah.
DR. APOSTOLAKIS: This is a factor of
about ten lower in frequency by comparison to the
previous generation of LWRs. That's not quite
accurate. In fact, it is inaccurate.
It is a factor of ten lower than the
regulatory goal of ten to the minus four. There are
many LWRs right now that have core damage frequency
ten to the minus five or less. So it's less than the
DR. POWERS: There is a body of opinion
over here that thinks that that may be true for
operational events, but not for the total core damage
DR. APOSTOLAKIS: That's right, but I
don't think that's what they meant here.
DR. POWERS: Well, I think he should be
looking at all of those things.
DR. APOSTOLAKIS: This is a factor of
about ten lower in frequency by comparison to the
previous. I don't think you have any basis for saying
that it's a factor of ten lower than the current
There are plants that are low even now.
DR. POWERS: Plants that certainly claim
to be low. That's right.
DR. APOSTOLAKIS: That's right.
DR. GARRICK: But you do have to remember,
George, that the PRAs still are limited in scope with
respect to such subtle issues as modeling uncertainty.
DR. APOSTOLAKIS: Sure.
DR. GARRICK: And a real genuine treatment
of uncertainty, which is still lacking in a lot of the
DR. APOSTOLAKIS: What I'm saying is that
it should not be the intent of a document like this to
pass judgment on the current generator of reactors.
The factual statement is that this is a factor of ten
lower than the goal. Now, whether it's reality is a
DR. TODREAS: Yeah, the objective of this
was to report reality, not to pass judgment. I mean,
certainly your statement and your point is clear and
noncontroversial. If this goes over the step, then --
DR. APOSTOLAKIS: Well, then it seems to
me that somewhere else you should say that these
probabilistic risk -- I mean that these goals that are
being stated here should be from all modes of
operation, from all -- you know, to make sure that --
DR. TODREAS: That's the second sentence,
an additional sentence that we could put after that.
DR. GARRICK: But the real thrust of this
was the recoverability issue. If you're going to have
a goal and improve on it, you'd like to, if you have
another Three Mile Island, to be able to recover the
plant, and that's why there was --
DR. APOSTOLAKIS: So plant damage we're
DR. GARRICK: Yeah.
DR. APOSTOLAKIS: Not core damage.
DR. GARRICK: And so the other thing
that's important, too, with respect to words like
"possibility" is that we were trying to be extremely
sacred with respect to what's in the box. The rest of
this is discussion and explanation, but it's what's in
the box that we were hopeful --
DR. APOSTOLAKIS: "In the box," what do
you mean by "in the box"? Which box?
DR. TODREAS: Well, in the box at the top.
DR. APOSTOLAKIS: Oh, oh, oh.
DR. TODREAS: But nevertheless, John, as
I said, the follow-up does take the write-up and
transfer it to metric, but what's in the box, do you
see what's in the box now, George? Is the specific
DR. APOSTOLAKIS: Yeah.
DR. TODREAS: So there you can go after
core damage versus broader. That would affect the
very specific goal.
DR. APOSTOLAKIS: And also I'm not sure
that you need both the likelihood and degree. A very
low likelihood of plan damage, period. At this high
level I think that would do it because plan damage can
be anything, and then you can define plan damage as
something I can recover from very easy.
DR. TODREAS: No, but see, degree is in
there because degree leads to the ability to recover.
DR. APOSTOLAKIS: Yeah, but that's
inherent there. I mean it's understood.
DR. TODREAS: No, I mean, you could have
plant damage extent across a spectrum, and we wanted
to cut that spectrum back. that's why the word
DR. APOSTOLAKIS: I think very low
likelihood and degree -- that doesn't sound good to
me, but --
DR. TODREAS: Okay.
DR. APOSTOLAKIS: -- because the
likelihood refers to the degree, right? It doesn't?
DR. TODREAS: No, I don't see it that way,
CHAIRMAN KRESS: I think the two go
together. I'm with George on this one. You have a
likelihood of something. That something is a degree
of core damage, and there's a spectrum, but the
likelihood goes with --
DR. APOSTOLAKIS: I want to have very low
probability and the non-damage states. What does that
DR. TODREAS: You say likelihood of
significant plant damage, but I think you have to
qualify it or add something to it some way.
DR. APOSTOLAKIS: but you have to say
something as to which noun the word "likelihood"
refers to. Likelihood of what?
CHAIRMAN KRESS: Core damage. It's the
likelihood of core damage of such a degree that it is
DR. APOSTOLAKIS: That's the correct --
yeah, that's the complete statement.
DR. TODREAS: Okay. Except we are not
going to go in in the box statement of the
recoverability from that explicitly. We just got all
tied up on that.
DR. WALLIS: Now, to be general, your core
damage also includes what happens to it when it is
taken out of the reactor.
DR. TODREAS: Yes.
DR. WALLIS: And put in a pool, for
DR. TODREAS: The whole --
DR. WALLIS: The whole smear.
DR. TODREAS: Okay.
CHAIRMAN KRESS: Do you feel like we're
picking on you, Neil?
DR. TODREAS: No, because what I was going
to do, I was going to request from the Chairman that
we get a letter with some suggested comments and --
DR. TODREAS: -- and I did.
DR. POWERS: The only one that can request
letters from us is the staff and the Commission.
CHAIRMAN KRESS: We only write letters to
DR. POWERS: We only write reports.
DR. APOSTOLAKIS: -- write to the
Commission commenting on the goal.
DR. TODREAS: We'll take your comments and
suggestions and views any way we can get them, but
they would be helpful.
DR. APOSTOLAKIS: By the way, in two or
three days there will be a transcript available.
CHAIRMAN KRESS: Yeah, transcription.
DR. TODREAS: That's fine.
Let me go to number ten, which is the
economic goal. Two points here.l In the discussion
of economics, the word "clear" is here with
considerable debate. Again, there's several
The pragmatic and certainly the majority
viewpoint was that if nuclear power of these nuclear
energy systems are going to have a future, they're
going to have to penetrate a market, and the only way
you penetrate a market, particularly given the history
of nuclear power costs, is for the new product to have
a clear advantage.
The other viewpoint is that nuclear power
is going to be needed in the future. There will be
environmental imperatives that will promote it and
draw it in, and it's unfair to require that it have a
clear advantage. All it needs to do is be
competitive, available, and await the demand from the
evolving market, which will emphasize new
environmental points of view.
DR. WALLIS: Well, presumably all you have
to do is put the environmental cost into the cost and
add up all of the costs and then your statement is
DR. TODREAS: Yeah, well --
DR. SHACK: What as a technology goal, I
don't think clear -- certainly as a goal you'd want to
have a clear advantage. Now, whether you need that to
be economically competitive is another question
DR. TODREAS: Going back to Graham's
point, what I interpret you're saying is take all of
the energy systems take all of their costs and make
them internal to them.
Interestingly on the NERAC Committee where
we've debated this one extensively, the non-nuclear
members, and particularly the non-nuclear economic
people basically say that will never happen. Don't
hold that as a pipe dream. Proceed and compete on the
situation as it presently exists, and effectively
don't wait for the non-nuclear energy systems to
actually have their extrinsic costs picked up.
So while it sounds great, we all agree
DR. WALLIS: It's like Safety and
Reliability 3. Maybe even if it seems unattainable
you should try.
DR. TODREAS: But we basically didn't want
to -- well, let me actually back up and ask you again.
Your point I got was an observation that if other
energy systems made their external costs intrinsic,
then this would fall out.
DR. WALLIS: No, I think it comes out
politically, too, and if the coal plants in the Middle
West that claim the fish in the New England lakes,
then that is a cost to somebody, and it's not a
negligible thing. It figures out in the political
DR. TODREAS: It's a huge cost.
DR. WALLIS: Right, right.
DR. TODREAS: Well, we agree. The
question will then come when you make this judgment
have you brought in into the alternatives their full
life cycle cost.
DR. WALLIS: Right.
DR. TODREAS: We're together on that.
And the only point I was making, the
advice we got is don't hold your breath till
officially those are subsumed, and in fact, those
people are not pushing that these other alternative
energy sources should subsume and have them made
visible, which is what I think the real deficiency is.
Okay. And then finally on Economics 2,
the question came up and came up fairly strongly: why
have it? If you've got Economics 1, you've got the
financial risk reflected already in the life cycle
cost, and so Economics 1 effectively is a complete
The response to that was to get nuclear
energy systems going, somebody is going to have to put
up the capital to start with, which is a risk capital,
and although all might be balanced out, ultimately in
the life cycle cost analysis, you still have to come
up initially with this capital, and that is going to
need to be bounded, and therefore, it needs to be
DR. WALLIS: Well, I'm not quite sure
here. It seems to me that one and two go together.
If the nuclear energy systems have a tremendous cost
advantage and they're very profitable, people will be
willing to take more risks to invest in them. So
they're not independent, as you know.
DR. TODREAS: Yeah. That's what I just
got finished saying. I agree with you, but at the
beginning of the project, you still have to put up an
investment, and it's still a risk, and if that amount
is focused on minimized or comparable, then getting
the ball rolling is easier.
And so Economics 2 was put in there in
reflection of that view.
Okay. So then the last figure is just a
summary as to where I've been, but an important
summary. So let's go to that.
I've done it in three bullets. The first
bullet is to reemphasize to you that future reactors
fall in three categories or more, but at least three:
those that are certified or derivatives of certified
designs, those designed to a reasonable extent and
based on available technology, and then those in
conceptual form only, with the potential to more fully
satisfy the Gen. IV goals, and it's this third group
that these goals are directed at.
There's a lot of activity in the second
one. You'll hear about the gas reactor, IRIS, et
cetera, but these goals are directed at Gen. IV plants
in the 2010 to 2030.
DR. WALLIS: Well, this is true. I'm
sorry, but it seems to me that a case could be made
that present plants satisfy almost all of your goals,
except for this off-site emergency response one; that
they're becoming more economical; they're profitable;
that they're safe. They have a low probability of
I mean it's all done already.
DR. TODREAS: Yeah. With some respect to
you, Graham, if you go back to Sustainability 1, you
will get into one hell of an argument that present
plants or advanced ALWRs or anything on the once
through fuel cycle is responsive to the sustainability
goals, one, two and three, to enough of a degree.
That's where the argument is focused.
DR. POWERS: I mean, it seems to me then
you're complaint, your argument is with Congress over
the reprocessing issue.
DR. TODREAS: Or recycling, but there's no
argument. What we want to do and what we've got
imbedded in this program is an ability to reexamine
the fuel cycle, and so my point is this.
DR. POWERS: I mean that seems like a big
enough challenge that I would leave the plant alone
and go reexamine the fuel cycle.
DR. TODREAS: The plant is a piece of that
fuel cycle, but when you say that plants in the --
either operating plants or the first two out of the
three bullets meet these goals, they don't -- the
sustainability goals is a spectrum, of course, on
there, and there are views that with regard to
nonproliferation, with regard to waste those plants on
the once through fuel cycle are good enough.
But if we're going out 30 years, we get an
opportunity to do something better in that, and even
if you're debating the whole spectrum of people who
impinge on nuclear power decisions, they won't accept
that the operating plants are good enough on those
That's where it's focused.
CHAIRMAN KRESS: Actually our assumption
at this meeting in general is that NRC will be faced
with licensing some sort of new reactor or Gen. IV
reactor or Gen. III reactor. Therefore, the question
is a bit moot, I guess. What we're interested in is
what are the challenges that are going to be faced
through the regulatory process when and if such a
design comes forth.
We know how to license the present
reactors. So, you know, I think it's a different
subject as to whether the present reactor ought to be
the next iteration or whether or not we should focus
on the advanced reactors.
This is an Advanced Reactors Subcommittee.
So I'm making the assumption that there will be some
sort of advanced reactor that we have to deal with in
the regulatory process.
DR. TODREAS: Okay.
CHAIRMAN KRESS: That's just to put things
DR. TODREAS: Yeah, I would just say a
follow-up to this along the lines you're talking about
is what I was prepared to discuss later in the
afternoon, the challenges, but my challenges are going
to be technological challenges coming out of the fuel
cycle. That's the bottom line.
CHAIRMAN KRESS: Okay.
DR. TODREAS: Okay. Then the second
bullet says we're looking for a range of design
options that respond to various marketing demands, and
I've got those in the four subpoints, and then the
final bullet down here is I think what we started off
agreeing on earlier in the discussion, that the
dialogue, at least my point is the dialogue between
the regulators and the designers relative to advanced
plants, and I'm talking there about these Gen. IV
plants has got to be framed to promote and encourage
fundamental design evolution, revolution directions.
And in that sense, the interactions that
come out of this I think require -- here I'll mention
the word "risk" now -- require the development of a
regulatory framework which is based on risk based
And I think we need to move to that kind
of structure and certainly that kind of dialogue as
you interact and as the staff interacts with the
conceptual and the development of these advanced
That's the bottom line message.
CHAIRMAN KRESS: Questions or additional
MR. LYMAN: Ed Lyman from Nuclear Control
I think that there are a few goals that
are really missing from this whole formulation. First
of all, under sustainability you refer to one that
minimizes, that a goal is minimizing and managing
nuclear waste, but at the same time, you really should
impose a requirement that the routine emissions from
the entire fuel cycle, as well as, let's say,
occupational exposures are also minimized because one
of the concerns with fuel cycles that involve
reprocessing are these additional routine emissions,
and you have to balance whether the reduced risk in a
repository is justified by increased short-term
So that's really something you have to
keep to minimize at the same time or it doesn't make
Second of all, under the financial goals
issue, you didn't really dwell on the one that
requires or suggests that the financial risks should
be comparable to other energy projects, and I was
wondering if in that context you would also have a
requirement then that Price Anderson protection not be
extended to Generation IV plants because other energy
projects don't require that kind of protection.
DR. TODREAS: Yeah, on the first point you
brought up, the specifics of that have been recognized
and will come up in Safety and Reliability 1 because
there we are talking about across the whole fuel
cycle, and those routine emissions are picked up
there. They could be picked up either place, but
that's where they come up.
And on Price Anderson, we didn't get into
the specific item within the structure of the goal
that can be picked up and debated. It's been debated
to some extent, but we didn't pin it down and resolve
I know that's coming up legislatively.
MR. BARRETT: I'm Richard Barrett. I'm
with the NRC staff.
And my question relates to the methods
that we use for estimating the likelihood of core
damage and the likelihood of release of radioactivity.
If NEI is correct and we have 50,000 new
megawatts of capacity out there, and those are modular
reactors -- that's 500 cores, and in an environment
like that you find yourself striving for lower and
lower core damage frequencies, and as you do that, you
begin to put more and more stress on the current
methods of estimating core damage frequency, and you
begin to get to the point where many people think
you're beyond the capability and the limitations of
the method and the ability to have a complete model.
And in addition, as you move to different
types of reactors, you find that you're depending less
and less on highly reliable, redundant, and diverse
systems and more and more on the intrinsic capability
of the core itself to withstand these accidents, and
to withstand them either indefinitely or for long
periods of time.
And, again, the methods that we have today
really don't deal very well with this kind of
intrinsic, passive capability.
So my question to you is the stated
purpose of your effort is to stimulate innovation in
the design of the reactors, and my question is: could
you also complement that with trying to stimulate
innovation in the methods that we use for analyzing
the risk associated with these reactors?
DR. TODREAS: Yeah, I would answer that
two ways. First, it's a good suggestion and a fair
suggestion. There's nothing implicit in -- what's
going to come out of this fundamentally is a spectrum
of concepts to focus on, but much more than that, an
R&D road map of activities to flesh up those concepts
and the methods associated with those concept
development is certainly part and parcel of that. So
we could do that.
The other thing though that I'd say
implicit in a response is, you know, if the future
were to evolve the way it is and even if we were to
develop the methods, and we're going to have to reduce
core damage frequencies further to get a desired
output. So that really leads you to say that if you
go with concepts now that are clones or like -- I'm
talking about 20, 30 years down the road -- that are
like these, you're going to reach a point where the
methods can only go so far based on the existing
approaches, and so that's a clarion call to change
those approaches and go toward -- well, first, you go
toward situations that avoid core melt, but that's
very limited in a sense that what you really want to
do is do what Dana Powers was talking about.
It's not core melt. It's the fission
products, and it's the radioactivity in the dose from
that, and that's what you've got to get after.
So I would say we certainly would accept
and develop methods, but what we are trying to do is
stimulate. I'm talking about real innovation, beyond
that, to try to open up approaches that really change
the playing field.
MR. HOCKRITTER: Larry Hockritter, Penn
It's not clear to me why in your
conclusions you have to have small versus large power
ratings. It seems like you're biasing yourself
already towards a particular class of designs.
DR. TODREAS: Yeah. Yesterday I presumed
the whole layout of this program was announced or was
explained as an international program with eight to
nine countries now, and one of the goals of the
program in all the specific directions is to come up
with design solutions or concepts that meet markets
internationally, and there are some international
markets, and also if you listen in the United States,
too, depending on the grid size, there are some
markets that have a priority toward low rated systems.
And so you have some of those, and then
you also have the traditional, if you talk about Asia,
Japan, Korea, Taiwan, large systems.
So inherent in the whole program, since
it's looking at worldwide markets, we're going to have
this dichotomy, these two parts, and not one reactor
thrust or direction is going to meet them. So you're
going to have to come up with systems in both
Now, your point may be fine, but they're
not going to be sellable in the United States or the
industrialized world. That's fine, but we'll have a
product for that. We just may not use the other
MR. KHADAMI: My name is Presar Khadami.
I'm with the NRC staff.
If I understand the rules by which the
South Africans are trying to license their plant, one
of their goals is that in the long term the concepts
employed should be amenable for society to make a
decision that higher levels of safety need to be
obtained from these energy systems.
And therefore, one of their goals, as I
read it, and if I should be corrected, I'd like
somebody to point this out; one of their goals is the
design should be amenable for society to demand higher
levels of safety at some future time if we take, you
know, these systems as operating for many decades.
Where does such a concept fit into the
kinds of goals that you have articulated?
DR. TODREAS: Okay. On this let me give
you a brief answer and ask for some help because I am
not knowledgeable about a specific or the specific
South African drive that you're talking about. I just
haven't interacted with them specifically.
I would say that even though these are
general, we are going to have some kind of constraint
because we're going to come up with a set of specific
metrics that go with each of these goals. They're
going to be as we go on a year or two -- there's going
to be some numbers and some specificity here . So.
There's going to be a little bit of a lock-in, and
that sounds to me like it's inconsistent.
The way I interpret what you're saying is
you come up with a design. Society decides they want
more safety, and so this design has somehow got to be
expandable or have margin or a way to capture more
safety. That's how I understand it.
So I don't know the answer. These goals
have been pushed in through a discussion with the so-
called GIF countries, of which South Africa is a part
of, and we didn't get any effective comment back from
them that's relevant to what you said.
But if Andy or somebody else can speak
specifically to that, that would help me.
DR. SLABBER: Mr. Chairman, the South
African concept, the baseline was to use existing
technology as far as possible, existing technology
that has been qualified and tested and proven to be
acceptable for use in the PBMR&S, and with a basis
that the fuel is the central point of focus.
And within that framework, we do the
system design, that it fulfills the requirements that
imbedded in the design without reliance on operator
actions is imbedded a term, and I again say, in
inverted commas, inherent safety and small units, and
usable for not only producing nuclear power, but also
some other usable byproducts specific for South
DR. TODREAS: Can I build on that maybe in
answer to his question? You stay there because I'll
I would say with that focus and the
ability, as you went to successive improvements in
fuel fabrication and fuel reliability, you could
actually enhance your safety profile if the key focus
is fuel, and that would be an answer back to how you
reflect the future, the fuel.
DR. SLABBER: Yes, and I think the
objective of any new innovator system should be to
improve, but there is a limit because it's also
costly. So improvement, the improvement for public
acceptance, improvement of safety, that the boundary
made improvements so that you do not have to shelter
and evacuate, but these are all factored in to provide
a facility which is still affordable and reliable.
CHAIRMAN KRESS: Thank you very much,
At this time I'm going to declare a 15-
minute break. Be back at 20 till.
(Whereupon, the foregoing matter went off
the record at 10:26 a.m. and went back on
the record at 10:45 a.m.)
CHAIRMAN KRESS: Before we move on to the
next speaker, I want to reiterate my announcement I
made this morning, that we are changing rooms for this
afternoon's session, and the room we're changing to is
the usual ACRS meeting room, which is on the second
floor of White Flint 2. There may have been some
confusion in people's mind.
And if you're signed in this morning, we
will have a -- you have to have a badge to get up
there, and there will be a temporary badge available
for those people who have signed in at the security
desk in White Flint 2 lobby, and that will be
available after lunch.
But if you haven't signed in at all or are
not currently badged, you will need to go through that
and get a temporary badge before going up to the
So with that little aggravation, we'll
move on to the next talk, which should prove to be
very interesting, and as I mentioned earlier, I have
no introductory comments. So you have to introduce
DR. KADAK: Thank you.
CHAIRMAN KRESS: And then I'll turn it
over to you.
DR. KADAK: My name is Andy Kadak. I'm
professor of the Practice at MIT. You can ask me
later what that means exactly.
I was formerly a president and CEO of
Yankee Atomic Electric Company. So I've been able to
see directly and experience the strengths and
weaknesses of the NRC regulatory process, and I'll
just leave it at that.
DR. KADAK: When I first came to MIT --
DR. POWERS: Because if you went through
all of the strengths, it would take too long.
DR. KADAK: Absolutely.
DR. POWERS: I understand.
DR. KADAK: When I went to MIT in 1997 as
a visiting lecturer, Professor Ballenger and I engaged
about 11 students under an American Nuclear Society
program called the Economic and Environmental
Imperative, and it was aimed at stimulating student
interest in looking at innovative, new reactor
technologies, and to see how we could make nuclear
plants competitive, safe, and politically acceptable.
In 1996, the students chose a pebble bed
reactor as the technology to develop since it appeared
to best meet our attribute.
We then convinced the Idaho National
Engineering and Environmental Laboratory that, of this
particular fact, and they supported much of our
research for the last three years.
Overall our objective is to develop a
conceptual design of a complete power plant based on
the concepts and ideas that we formulated in 1998.
We're now working in the following areas,
just to give you a sense of the scope of our effort.
We're doing and developing a fuel performance model,
which includes and will include the manufacturing
aspect of it.
We're doing some experimental work on
silver and palladium, effect on silicon carbide.
We've got a core neutronics capability, and ultimately
hope to verify and validate using MCNP, a lot of the
We're developing a balance of plant design
and a simulation capability to assess normal operating
We're also working in the area of safety,
loss of coolant and air ingress analysis. We've done
some work on nonproliferation, waste disposal, and
we're also now engaged in what I call true modularity,
namely -- and this is the innovation -- true factory
manufacture of essentially the balance of plant for
We are also working with the University of
Cincinnati on developing of a burn-up monitor for
If we get additional funding, there will
be work on advanced INC with Ohio State. We're
looking at management issues and a PRA.
So ultimately, if our work is successful
and we continue developing this concept, our plan is
to build a combination research and demonstration
facility to test the technology, help validate the
technology and operation, and essentially use it as a
continuous test bed for the life of the plants should
they be built in the future.
This is sort of an introduction to what
I'm going to talk about today, which is this license
by test, which I've been thinking about for many
years. I've talked to many of the NRC staff about the
Now, this presentation that I'm going to
make today does not claim to have all the answers
about how such a process might work, but it is meant
to address some of the high level issues and the
approach that we might consider.
And to determine whether this concept is
workable, it is recommended, and that's my bottom line
recommendation, that the NRC, we and other interested
parties work to see if such a process can work rather
than jumping on all of the reasons that it can't.
So with that, let me just begin. Here are
the challenges as I see them. The regulations, as you
all know, are focused very much on water. The
knowledge of the technology, particularly in new
technologies -- forget the pebble bed for the moment.
This is generic -- knowledge of these knew
technologies is generally lacking, and the
infrastructure to support some of these new
technologies is also lacking.
We've heard plenty of that yesterday,
regardless of whether it's gas, liquid metal, lead
bismuth, whatever the technologies are.
And changes in the system, what I call the
system is the regulatory system, take a very, long
So how do you introduce a new technology
in less than a lifetime? And yesterday I heard hints
of lifetime project.
We need to go back to the basic safety
fundamentals. We need to work within the existing
regulatory high level objective, use -- and here we go
-- very early in the game, risk informed, which I
define as risk based with deterministic analysis,
approaches to determining safety; assess our gaps in
the knowledge, especially if it's new technology to
see what we understand and what we don't understand
very objectively; prioritize namely what are the
significant risks associated with what we don't know
and what we do know; and then try to license this
thing by test.
Well, here we got. Relative to
establishing the safety goal, we would use a public
health and safety goal, not a core damage frequency,
and I think you were sort of getting at that yesterday
in terms of releases.
You look at this public health and safety
goal, and then you start to define your plant risks,
whether they be normal operating risks, events,
transience, accident scenarios, and then identify the
safety margins as bets you can using deterministic
analysis. Then begin or attempt to quantify the risks
as you know them using a PRA, and then show defense in
depth, and what I will describe later about defense in
depth is how many barriers are there to prevent a
CHAIRMAN KRESS: Is that what you mean by
defense in depth?
DR. KADAK: That's what I mean by that.
And I'm not defining the barrier, and how
do I deal with the uncertainties that recognizably
exist in this technology.
Next slide, please.
The risk informed approach then really
attempts starting with the safety goal, and it's a
public health and safety goal, by applying what we
know and using the probabilistic techniques that we do
know in a scoping kind of a sense. We will obviously
not know the performance of helium high temperature,
high temperature helium turbines or compressors
because the size that we're talking about hasn't been
built, but we can estimate it based on other
Are these health and safety goals
something different than the quantitative health
objectives that we currently have?
DR. KADAK: they would be based on
fatalities, ten to the minus -- pick a number -- ten
to the minus six. Start at that level.
CHAIRMAN KRESS: Yeah, but do you think
that those we now have are sufficient or do we need
DR. KADAK: I would say at that level it's
DR. POWERS: Why do you focus on
DR. KADAK: It's an easy measure. You
could talk about injuries, if you like as a separate
DR. POWERS: I mean if we're going to
learn something out of accidents that have occurred,
the most transparent consequence of Chernoble has been
radiation injuries rather than fatalities.
Line contamination could arguably be the
other thing that we've learned. Why not change the
measures in response to things we've learned?
DR. KADAK: We could do that. I'm not
limiting it. I'm just saying establish something that
everybody is comfortable with, and I mean societally
comfortable with. And if it talks to land, if it
talks to injuries or if it talks to fatalities,
fatalities is the one that we now have.
CHAIRMAN KRESS: Well, you know, part of
the purpose of this meeting is to identify regulatory
challenges, and my question was aimed at saying do we
have appropriate let's call them safety goals now or
should the Commission be thinking about something
different for safety goals for the advanced reactor,
and that --
DR. KADAK: My sense right now is we have
already essentially established the policy that
says -- we established the public health and safety
goal. Let's start there. If there's more that needs
to be done, add it, but I don't see that as a priority
issue right now.
From what I understand of the British
system, they're trying to harmonize safety goals
across all technology, and perhaps we can learn
something from that to be able to judge whether
nuclears are in the right ballpark.
CHAIRMAN KRESS: Okay.
DR. KADAK: So we would then apply these
deterministic and probabilistic techniques as best we
can to see if the goal is met, and then using the
risk-based techniques, identify dominant accident
scenarios and what critical systems and components
need to be tested as a functional system.
And in this case I'm trying to avoid the
use of design basis access. I'm trying to see what
really matters for safety and use the risk approaches
to identify those.
The next slide gives an approach that I
think has been used in the past where you go through,
you know, the risk informed approach, namely,
identifying on a very high level basis the issues of
protection of the public, evaluate risks against the
safety goals, use the PRA to quantify obviously larger
uncertainties, limit core damage, mitigate releases,
and then mitigate consequence.
Now, this is sort of a standard kind of
approach. What I would suggest is that's where you
start, and the master logic diagrams would be more or
less technology specific relative to the kinds of
vulnerabilities of the particular technology might
The next slide gets into a description of
a master logic diagram, but that's for water reactors.
One of our students at MIT is now attempting to try to
define this better for, say, the pebble bed reactor,
and we're going to start with a basically different
approach at least from my perspective, and that is,
you know, starting with the plant and how do I protect
the public working backwards, and what events can
We're going to try to do a different
master logic diagram on that basis.
Next slide, please.
This chart here, which you can't see very
well, but it's in your handout, is a summary of what
the South African national nuclear regulator is using
for their assessment. They've got a very similar
system to what I'm proposing, at least at a higher
level, and they developed some requirements that
starts from the public health and safety goal and
establishes various safety criteria in a range of
events which I think we heard about yesterday.
It's in the handout, and hopefully you can
read it better, but I bring that up only to allow one
to see that there is a logical frame of reference from
which to proceed to establish such a process of using
risk informed to establish and correlate that with the
public health and safety goal.
The next slide, please.
We do have an existing regulatory
structure, and I'm still trying to do this in less
than a lifetime. So what we're going to try to do if
we get a chance to is -- and it's already been
discussed, I think, by Exelon -- and that is review
the existing regulatory structure for the gaps that
exist relative to that particular technology. For
example, as far as I know, there's no error ingress
safety criteria. We might need to have such a thing
developed, but identify those kinds of issues as you
look at the existing regulatory guidance.
And, in fact, look at the general design
criteria and say how do we and how can we implement
those, given what we think are the high level safety
objectives that we've established in the previous
Where it gets confusing and where it will
get difficult is trying to meet the general design
criteria for non-standard or non-order technology, and
it's in the details that you really get hung up, and
that's where the whole process of show me that it
doesn't require this criteria happens.
So we're trying to say by reviewing the
existing structure, applying it to say the pebble bed
reactor, and then being able to say on a risk based,
you know, foundation what does and does not require it
in terms of the fundamental design for the regulation
that would apply to that.
So, and I use the word "design basis
accidents" using risk based techniques. I really
wanted to keep to the word design the dominant
accident sequences using risk based technique, which
you would then analyze to try to assess how much
defense exists in those accident sequences.
DR. WALLIS: Can I ask you something here?
DR. KADAK: Surely.
DR. WALLIS: I mean, you seem to be
applying what we do today to what we might do
tomorrow, and did you question whether we really need
design basis accidents in their present form?
DR. KADAK: My approach would say --
DR. WALLIS: Or would it be replaced by
something else which might be less plant specific and
be more effective?
DR. KADAK: The process that I would
recommend is developing dominant accident sequences as
part of the regulatory process, and don't call them
design basis accident.
DR. WALLIS: But you just did.
DR. KADAK: Well, I made a mistake.
DR. KADAK: I was revising my slides, and
I was looking for design basis accidents, hopefully
not to include it, but I made a mistake. It should be
establish dominant accident sequences. Okay?
CHAIRMAN KRESS: If you go back two slides
to the one we couldn't read --
DR. KADAK: Yes, the big -- yes.
CHAIRMAN KRESS: It seemed to me like
that's at least three points on it, a frequency
DR. KADAK: Right.
CHAIRMAN KRESS: It seems to me like such
a curve encompasses all of the accidents, the whole
DR. KADAK: It attempts to cover them all.
CHAIRMAN KRESS: If you meet some sort of
regulatory requirement on this, and it may have to
have confidence limits or something, and then
encompasses the whole shebang, doesn't it?
DR. KADAK: We're trying to cover the
regime of accidents possible for this technology.
Okay? And looking at the categorizations placed under
A, B, and C, it appears to cover logically what one
would need to worry about, but I can't --
CHAIRMAN KRESS: So if you just tell the
designer or the license applicant that he has to meet
this curve -- I call it a curve -- at a certain
confidence level, what else do you need?
DR. KADAK: I guess --
CHAIRMAN KRESS: The thing that seems to
be missing to me is defense in depth. We can get into
DR. KADAK: Where I get hung up is for new
technologies doing that is going to be extremely
CHAIRMAN KRESS: Because it requires a
pretty good PRA.
DR. KADAK: It requires a good PRA.
CHAIRMAN KRESS: And a good knowledge of
the phenomena that go into the accident sequences.
DR. KADAK: Yeah, and a lot of data that
supports the probability --
CHAIRMAN KRESS: Which is the part that's
usually tempted to be covered when you have that
situation by defense in depth. That's why I keep
harping on we need a firmer definition of defense in
depth and how it fits into a regular or a system like
this, for example, with new technologies where you
don't really have core melts, and you don't really
have the standard barriers against fission products.
But, anyway, that's another subject.
DR. KADAK: Well, my sense of defense in
depth is how much margin do you have to, say, core
melt or in this case release.
CHAIRMAN KRESS: Yeah, that's a sort of a
defense in depth.
DR. KADAK: Sort of.
CHAIRMAN KRESS: It's not my definition.
DR. KADAK: Okay.
DR. WALLIS: What's your measure of
DR. KADAK: I hate to say this, but
DR. WALLIS: That to me always is an
ignorance factor than --
DR. KADAK: Absolutely, and I'm just
suggesting that when you introduce new technologies,
there will be a lot of uncertainties which you cannot
DR. WALLIS: Your engineering judgment is
maybe ultimately different from somebody else's. So
how do you explain or argue with that person?
DR. KADAK: It depends on the design.
DR. WALLIS: I think you have to be
quantitative in some measure which you can agree upon.
DR. KADAK: If you can do deterministic
analyses and show that the worst situation as was
presented, I believe, yesterday is acceptable and
analytically, deterministically. That's why it's not
purely a probabilistic approach.
Using the best tools that you have and, in
fact, being able to, as I will get to, the license by
test scenario to demonstrate such things, I think your
confidence levels will be greatly increased, and
that's the bottom line.
What makes me very nervous is just relying
on numbers with confidence levels because as we know,
even with our PRAs things happen that are not in the
DR. KADAK: Okay. If I could catch up to
where I was, okay, then if you'd just back up that
one, I want to -- to develop the defense in depth
basis using the natural physical attributes of the
designs, what that basically means is if there are
significant natural physical attributes and not so
much reliance on active systems or passive systems
that must function, you are in a much better position
to develop the confidence level you need relative to
defense in depth, and you can argue about how many
barriers or whatever, but that is a key part of this,
and that's a key direction, I believe, that the
regulators ought to encourage relative to new
technological develop, and that is natural physical
CHAIRMAN KRESS: I interpret that
statement to mean that there's probably less
uncertainty associated with determining the risk of
those than when you have a complicated system with
lots of barriers and lots of active --
DR. KADAK: That's the point. We want to
try to limit those active --
CHAIRMAN KRESS: Therefore, since you have
less uncertainty and higher confidence in the risk
results, the less defense in depth might be needed?
DR. KADAK: Again, the less defense in
depth is not the right term.
CHAIRMAN KRESS: Is that too big of a step
DR. KADAK: Now, the point is to
demonstrate the defense in depth exists and give
credit to natural physical attributes, I think is the
direction that I would be heading.
And then to whatever degree possible,
establish confidence levels in the analysis using risk
Next slide, please.
All right. License by test. Depending
upon the technology, and in my case it would be sort
of the pebble bed for an example, build a full size
demonstration facility. Perform these critical tests
on those components that you identified as dominant
DR. WALLIS: I don't quite understand
that. Are you going to have a near core melt or a
near containment failure in order to do a critical
DR. KADAK: Let's just say, for example,
if LOCA is a major accident sequence --
DR. WALLIS: Do you have a LOCA in your --
DR. KADAK: You would perform a LOCA.
DR. WALLIS: You would perform a LOCA.
DR. KADAK: Or to the degree, at least,
that you can validate your computer models and
methods. And that's why these physical features
become very important.
DR. POWERS: Have you imagined what the
environmental impact statement on this federally
funded examity (phonetic) is going to look like?
DR. KADAK: Sure, and what I didn't
mention and I probably should was that for the purpose
of this research, combination research demo facility,
we put a containment on it.
DR. POWERS: Well, I thought you just put
it in Idaho and nobody would care.
DR. KADAK: For the record, Idaho is a
beautiful state, has lovely people.
DR. KADAK: Nature abounds.
DR. POWERS: Probably do $10 million worth
of improvements in New Mexico.
DR. KADAK: Okay. So clearly it's a
research facility that needs to have a containment,
but the purpose of the containment is to prove you
don't need one, if that, in fact, turns out to be the
DR. POWERS: How would you do that? I
mean, suppose you ran this test and, indeed, it did
just fine, and some skeptical guy like Ed Lyman over
there came along and said, "But if you'd done a
different test" --
DR. KADAK: Well, that's what I want Ed
Lyman to work with us. When I said all interested
parties, I'd like to have Mr. Lyman, Mr. Lockbaum, and
Mr. Gunther involved in this because I think that's
part of the process.
DR. POWERS: And still no matter what test
you did, somebody else could come along and say, "But
if you'd just done this other test."
DR. KADAK: Yeah, but Mr. Lyman will be
explaining to this other person why these test series
are adequate, not me.
DR. WALLIS: Well, I think the problem you
get into --
DR. KADAK: Sorry.
DR. WALLIS: -- is the basis of scientific
testing is to try to disprove your hypothesis.
DR. KADAK: Yes, or to prove it. I think
you'd like to try to prove it.
DR. WALLIS: Of course, by the very fact
that you could disprove it, you would have had an
unacceptable release presumably. So it's a little
difficult to design that crucial test to disprove a
hypothesis that it's safe.
DR. KADAK: Well, again, there's a reason
for the containment, and obviously you'd be a little
more creative about the type of test you run so that
you understand what the possible outcomes would be,
but theoretically it's conceivable, and it obviously
depends on the plant and type of design.
DR. WALLIS: I guess we're asking these
questions because we're kind of intrigued by the idea.
DR. KADAK: Good.
DR. WALLIS: But we're skeptical.
CHAIRMAN KRESS: Yeah, one purpose --
DR. KADAK: Wonderful, marvelous.
CHAIRMAN KRESS: -- we attribute to
integral tests are to -- two purposes: one, to see if
there's something going on that we hadn't thought of;
two, to validate our computerized analytical tools so
that they can be used in an extrapolatory sense to
cover the things we can't do inn the test.
Would that be your view of what this test
might do for you?
DR. KADAK: Next slide.
The needs. Why? To validate analysis.
Okay? To shorten the time for paper reviews; to try
to prove in quotes what's debatable; to reduce
uncertainty, and this is very important; to show the
public and the NRC, and I include them as the public
in this case, that the plan is, in fact, safe.
And that's what it's all about. Can we do
the -- you know, can we try to melt the core? If we
believe that we can do it without melting the core,
DR. WALLIS: So what you should do is you
should give an operator carte blanche to try to melt
the core, and he or she will fail. Is that your test?
DR. KADAK: Depending upon the design,
yes. I mean, theoretically that would be the test,
but I would structure it more carefully than that.
DR. KADAK: See, we're going to hear about
radiological sabotage in a few minutes, I'm sure, and
maybe that's the test that Ed would like to run, but
we don't know yet.
Yes, I'm sorry.
DR. GARRICK: Andy, we have a bit of a
model for this in that we once had something called a
national reactor testing station, and we once had
something called the borax experiments, and we once
had something called the spurt experiments, all of
which have a kind of familiar ring as to what they
wanted out of those experiments in terms of what
Does that experience, just from the
standpoint of answering the questions of one scenario
versus another scenario, I want to test my scenario,
Dana wants to test his scenario, and so forth; is that
experience relevant at all in what you're proposing
DR. KADAK: I'm not sure, but I recall
some of them actually wanted to break fuel like no
DR. GARRICK: Right, but they were talking
about various degrees, and they tried very desperately
to come up with an experimental program that gave them
the biggest bang for the buck possible, and what they
were really trying to do was get closer to a
quantification of the loss of coolant accident, and
better parameter information with respect to the
containment and so forth.
DR. KADAK: Clearly, you know, that
experience would be certainly helpful, but again, I
don't have all of the answers. I'm just giving you an
idea of what I think might work, but how to exactly do
it and what to build on, I just am not all that
What I hope to do after this presentation
is you're so excited about this concept that you'll
ask the NRC staff to work with us to try to figure it
MR. LEITCH: Andy, I have a question about
your second bullet up there, shorten the time for
DR. KADAK: Yes.
MR. LEITCH: I'm not exactly sure what you
mean by that. Does that mean that the paper reviews
would not be as detailed or not exist at all --
DR. KADAK: No, no.
MR. LEITCH: -- in lieu of this test?
Or talk a little bit about would the paper
reviews be less detailed than they would normally be,
and if not, how would the time be shortened?
DR. KADAK: See, that depends on what
licensing action you have. Let's just take the most
recent paper review, AP 600.
MR. LEITCH: Okay.
DR. KADAK: All right? I'm told -- I do
not know -- it took roughly ten years. I'm told, but
do not have the number confirmed, it cost around $249
million, which included a lot of testing as well.
And the end of that process was a
certification, a piece of paper. What I'm suggesting
here is for $249 million I could probably get part of
a plant built that looks like a research facility that
could be used to answer some of these tests, some of
In terms of submittals, I don't see much
different in terms of what the design is. The
submittal would largely be here's the design. Here's
why we think it's comfortable and appropriate, and
here's the testing program that we're planning to
perform here to validate these areas that are in
question or to validate some computer code.
So the approval would be more of an
approval to conduct tests on a facility than to grant
a license or a certification. That certification
would come after the test had been completed,
hopefully successfully and whatever design
So I think in time scale, we're probably
going to be about the same, say, five to ten years,
you know, including the building the plant. What you
will have at the end of that process not only is
certification, but also a plant that theoretically is
DR. WALLIS: Are you asking for a kind of
full scale LOFT test?
DR. KADAK: Full scale LOFT test, I
suppose in the sense of a LOCA. There will be others
on a facility, and one of the things it avoids is
remember the scaling issue that you've had to fight
over? I mean, clearly the scaling issue sort of goes
away if you do a full scale plan or a large enough
scale to be able to say scaling is not a factor.
DR. POWERS: I still get hung up over
these. When George does a PRA, he comes up with more
sequences than I can count, and you're going to have
to validate all of them?
DR. KADAK: Not all of them, no.
DR. WALLIS: Well, some significant
fraction of them?
DR. KADAK: You'd validate obviously the
dominant accident sequences that are really important
for public health and safety. That's the ones that --
DR. POWERS: So maybe 12, 13 major full-
DR. KADAK: Probably.
DR. POWERS: And what happens if, I mean,
just one of them kind of goes awry?
DR. KADAK: Fix it. You make the design
change. That's why it's called a research facility.
DR. POWERS: Well, cleaning out a full
scale facility contaminated with radionuclides does
not strike me as a low cost operation.
DR. KADAK: Well, clearly you wouldn't do
these if you had any question in your mind that it
DR. POWERS: Oh. So there's a certain
level of uncertainty that I can't have.
DR. KADAK: That's right. I mean, clearly
you wouldn't build a plant that you didn't feel could
withstand the test.
DR. POWERS: You're going to have a hard
time buying the insurance policy.
DR. KADAK: Well, that's why we have this
containment. I mean, no --
DR. SHACK: Well, somebody has got to
clean up the mess just in case it goes wrong.
DR. KADAK: Well, again, the confidence
level basically is that of the designers and the
engineers after a lot of review and approval to say
that this thing will work.
I mean, clearly, you wouldn't do anything
stupid, and that's the point. If you have confidence
in the technology, you could do this. Maybe not all
technologies are amenable to this kind of an approach,
but those technologies that have the kind of margins
that I think exist relative to the melting or fuel
failure certainly could try.
But let me continue and you can get the
full scope here.
MR. SIEBER: Well, who would finance the
DR. KADAK: Good question. It is a
research facility, bottom line, and if, in fact, it's
as broad a scope as we are talking about here, I think
it's a legitimate government expense.
DR. APOSTOLAKIS: I think that's the way
you lose Mr. Lyman.
DR. KADAK: Well, he's going to be a
DR. APOSTOLAKIS: You wanted him to work
with you, but --
DR. KADAK: But he could be a player. I'm
saying that, you know, there's obviously some industry
money that's going to be required as well, but how
much of it is research and how much of it is
application and certification relative to usable
technology is the matter to be discussed, but clearly,
you know, this kind of facility would be, I think, a
government supported --
MR. SIEBER: Well, it seems like it would
be very expensive, and in a competitive environment
I'm not sure that licensees would be willing to ante
up a lot of money.
DR. KADAK: Well, let me just give you
some rough numbers. If my numbers about AP 600 are
right, that's, say, 250 million. I've done some
preliminary cost estimates to engineer and design this
facility would be around 500. A 50-50 split sounds
fair to me. It may not be the right numbers, but
that's kind of what we're talking about.
MR. SIEBER: In this facility you would
have active fuel in it?
DR. KADAK: Oh, yeah.
MR. SIEBER: So you would have to license
it just to have the facility, would you not?
DR. KADAK: That's, again, part of the
process. The licensing basically is the thing that
Graham was talking about. What is the NRC review and
So it would be licensed, if you will, as
a research facility.
Okay. Let me move on. The test that I
think would be required are, you know, you're never
going to get away from the traditional performance of
component. There will probably be some small scale,
integral tests to verify so that we don't have this
scenario about cleaning up fuel, but you then would
use these risk based techniques to identify the kinds
of accident scenarios that are important, critical
systems, critical components, some integrated tests
which may be in a smaller scale.
Next slide, please.
And the test that I was considering may be
more. I don't know if it adds up to 13 quite, but
loss of coolant, depressurization, natural
circulation, see if we can get it or not. In our case
we don't want it.
Rod withdrawal, reactivity shutdown
mechanism, cavity heat up and heat removal, and then
other key component failures that you find become
dominant in the PRA.
DR. WALLIS: Now, if you just look at loss
of coolant, there are all kinds of sizes of breaks in
all sorts of places.
DR. KADAK: Yes.
DR. WALLIS: So what you presumably would
do is you'd do a lot of analysis ahead of time and say
this is the one we're really worried about?
DR. KADAK: Could do that.
DR. WALLIS: Then you're going to miss Dr.
Kress' point because, you know, the whole purpose of
doing the test is to find out things that gave you a
DR. KADAK: We could do it by expression.
I mean, this facility, my hope would be it would be
designed in a way that it is, in fact, a research
facility with different abilities to blow down by
size, if that's the --
DR. WALLIS: So loss of coolant might be
a whole sequence of tests.
DR. KADAK: Could be, yeah. Again, I have
not designed it, but in concept, yes.
So next slide, please.
Additional tests. Oh, here. I guess I
put up to my 14 or 15 now. Balance of plant failures,
the traditional things that we worry about in
liability space, turbine over speed, failures of
various components, rod ejection or rapid withdrawal.
I'm not sure we want to do a rod ejection per se.
Cavity heat-up. Again, we want to
validate the core physics models.
DR. POWERS: Let's look at that control
rod ejection because it's a fun one to look at. The
scenario that we're now worried about is one where the
fuel had extremely high burn-up. How are you going to
do that in your test?
DR. KADAK: That would have to be outside
of the reactor. We can't do that for -- you know.
There would be a whole series of fuel tests as part of
DR. POWERS: Well, and the problem that
plagues the right ejection accident is an argument
over how it propagates within the whole course. So if
you do this test at the FABRI (phonetic) facility with
one rod, that doesn't answer the question. I need a
whole bunch of rods.
DR. KADAK: Well, I think we could do like
I said, a rapid withdrawal, and we could model it from
the standpoint of what we expect as a reactivity
transfer and to see whether those codes, in fact --
DR. POWERS: I mean, that's where the
argument is, is whether the codes are right or not,
and whether they give you the right amount of heat
going into the clad and not into damaging fuel.
DR. KADAK: Well, the first is the
reactivity. Then we can go to heat, right?
DR. POWERS: No. This is a time scale
where those two are very coupled together.
DR. KADAK: Okay. Then xenon, we talked
DR. WALLIS: Some would argue that the
technologies are fine, and that most of the major
accidents are caused by people doing something out of
ignorance, stupidity, whatever.
I don't see that as part of your testing.
I'm not quite sure how you would test it anyway.
DR. KADAK: Oh, we could do your earlier
DR. POWERS: Graham, I'm shocked. People
don't make mistakes out of ignorance and stupidity.
It's an error shaping factor.
DR. POWERS: Forcing factor. You've got
to learn this language, sir.
MR. LEITCH: Andy, would you be talking
about fully integrated tests here? For example, if I
may ask the question this way. In the start-up of a
normal power plant, there are those who would advocate
walking up to the generator breaker at 100 percent
power and opening it and seeing what happened. I
mean, I always thought that was a little like testing
para chutes, and what I'm saying --
MR. LEITCH: -- we would demonstrate that
the turbine would trip and that it had contacts that
would make the reactor scram, and we would demonstrate
separately that the reactor would scram.
But I mean, I really think some of these
integrated tests would unnecessarily put the plant
through perturbations that could be demonstrated
piece-wise. And I'm just wondering if you have
thought about the piece-wise demonstration of this or
would you be talking fully integrated tests?
DR. KADAK: I think what the final test
program ends up being is that which is judged to be
such that it can demonstrate where the safety concerns
are. Now, if there's too much of a strain, for
example, and the plant could just trip a breaker and
see what happened, and people say, "Well, I can get
the same information from these separate tests," I
think that would be fine.
I'm not here to design the test, but I
think that would be part of the process, working with
the regulator to develop what evidence do they need to
show the plant can do what we think it can do.
So it doesn't have to be the crazy.
Okay. The next slide, please.
Continuing on with the test so that it's
more than 15, dual performance, which gets to Dana's
question about, you know, high burn-up, cycling, most
heat-up, most accident heat-up, ingress to validate
this chimney question, and water ingress if you'd look
at the reactivity effect and the possible fuel damage.
My sense is those would be done probably
outside the core on varying degrees of fuel and
varying size of the facility, and I think the Germans
have done many such tests already.
Well, what I started talking about was a
prototype, and as a suggesting, using the pebble bed
reactor as such a prototype. It's built full sized
with the containment as I mentioned.
Implement the structure test program, and
as part of this process, and I call it a process, we
would develop what rules might be appropriate for
introducing new technologies that don't have, you
know, 25 years of regulatory history.
So we would not only test the facility,
but also see if this process that I've outlined can
work with new non-water technologies, for example.
And if, in fact, the process works, apply
it generically to other technologies. That was sort
of the idea.
And then if all goes well, you have a
certified design, and you have a reactor that's sort
of the fleet innovator, if you will, for the next 40,
50 years, however long the fleet exists.
Will this answer all of the questions,
categorically, no, but at least it gives us a good
shot at answering hopefully the most significant ones,
but in combination with all of these subtier component
tests and small scale tests, we'd probably have a
good, relatively high level of confidence about
critical safety performance.
Next slide, please.
Will this license by test instill public
confidence? I say yes, in the sense that it gives the
public -- giving the public and the media an
opportunity to observe these tests, hopefully the
confidence in this technology will be increased so
that you avoid -- and I'm sorry, George -- ten to the
minus pick a number is not understandable for public
communication, although it may be very well understood
here, but it doesn't really work out there. They'd
like to see this thing work, and if successful, the
core doesn't melt --
DR. WALLIS: Do you think using words like
one in a billion would be more appropriate?
DR. KADAK: You know, one in a billion
people still win the lottery, you know. So what does
DR. POWERS: I think in pursuing this
viewgraph, you ought to look at the experience they
had at the Phoebus (phonetic) facility, which was
doing an experiment, which amounted to melting down 21
fuel rods, two of which were fresh fuel and the rest
of them were irradiated, and the public responds prior
to the first test there, and how eager they were to
watch that particular test.
DR. KADAK: I'll look it up. I'm not
familiar with it.
CHAIRMAN KRESS: They had people with
placards marching around.
DR. POWERS: They were invading the test
DR. KADAK: Well, it could happen here,
too, but hopefully we will engage them long before and
get them to buy into the objective of all of this, and
if this approach works, I think it will encourage the
development of what we would all a more naturally safe
Next slide, please.
Well, how about the traditional regulatory
approach? I think we need to just ask a few people,
which I've done from time to time, and maybe they can
answer your questions about, you know, how well that
worked for them.
As you know, with the MHPGR, Candu and
Canadians, I think Westinghouse will have a nice
authority to tell them, and I think the AP 1000 is
still an open issue, and answers are not always
possible to the extent that it can always satisfy the
And I am very familiar with bring me the
rock process. I don't think it's very effective, and
maybe this approach is an alternative to that work.
So with that I'd like to conclude and
answer any other questions in the house.
DR. POWERS: I'm intrigued by your
students looking at the pebble bed reactor. Do you
have any of them looking at the potential for that
particular machine to be used for the fabrication of
DR. KADAK: We looked at proliferation.
Yes, we did.
DR. POWERS: Find out anything?
DR. KADAK: Yeah. In a normal operating
elevator reactor, the number of pebbles required to
accumulate eight kilograms of plutonium at end of life
is roughly 250,000, and the isotopics at that level
are very uninteresting for a nuclear weapon.
If you're deciding to do that, well, let's
only run the pebbles through one pass to accumulate
eight kilograms. That's around 800,000, which makes
it an unlikely target for delivery.
You could be clever relative to the
technology, but in that case, as in all nuclear
technology, you need extrinsic measures to detect --
as you recall, the system is a closed system, does not
have a spent fuel pool, and so even at that point it
would be very difficult to get, but we've looked at
that, and we need to be real careful in that area.
At some point I hope you invite me back to
talk about our work because it's really quite
CHAIRMAN KRESS: Other questions?
DR. KADAK: My new collaborator.
MR. LYMAN: Ed Lyman, NCI.
Here's a practical question. So you're
proposing that the test facility go with a containment
which is not the same containment that the pebble bed
is planned to have?
DR. KADAK: Only because it's a research
MR. LYMAN: Right. So I've heard the
argument that the passive cooling of the pebble bed is
incompatible with a leak tight containment and it
would interfere with, for instance, the design base
LOCA heat removal. So --
DR. KADAK: Well, we'd have to look at
that to see whether or not and how we could make it
compatible for this particular facility. We'd have to
look at whether, in fact, we need to make additional
modifications to the facility to accommodate the
passive cooling feature.
MR. LYMAN: But if it could be done for
the test, then it could also be done for the real
thing, I guess, if you had to.
CHAIRMAN KRESS: Yes, ma'am. Please
MS. FABIAN: Hi. Teka Fabian from Nuclear
It's not as exciting as melting down the
core, but I'm wondering if as part of your conceptual
design process you've done the sort of things that the
fusion materials program has done, is looking forward
to end of plant life and looking at lower activation
materials that are easier to dispose of, possibly
easier to resmelt and reuse in a nuclear facility,
designing the plant for decommissioning using robotics
and remote technology; if any of this has played a
part in the design process.
DR. KADAK: Not at this stage, although we
are following what's going on in Germany as they're
decommissioning their AVR reactor.
Clearly, one of our initial objectives was
to design a plant with decommissioning in mind, also
having a lot of personal experience about
decommissioning the Yankee Row plant. So I'm very
sensitive to that issue.
But we haven't really looked at it, and
we're not really at that level of detail yet.
MR. HOCKRITTER: Larry Hockritter, Penn
As an AP 600 design certification
survivor, I'm familiar with the testing that we had
done and a number of questions that we got from the
NRC, which were large.
But when you structure a test program,
usually you build on separate effects tests to try to
identify and create a model that you then put into an
integral code, and then you use integral tests for
verification of that model.
I think one of the problems that we have
in the water reactor technology world is that we don't
have very good integral systems tests. The loft
tests, which are the largest integral systems tests,
that we've all used for a code validation, there's a
lot of questions on the accuracy of the
instrumentation, which are really measuring versus
what you think you're measuring, and so forth.
And there may be a lot of potential
problems for that in this type of a program unless
it's very, very structured very carefully, and then if
you add the instrumentation that you want to add, you
can start to distort the things that you're trying to
So I think that you're -- I like the idea.
Okay? But I think that you really have a background
of tests that you're going to have to provide in
addition to a large, full scale test where you build
the technology so that you can have confidence then in
the code that you'll use to predict the test, which
you'll then try to run in the facility.
Otherwise you may have some unpleasant
DR. KADAK: I think a lot of that stuff
that we're talking about, some of which at least I
should say has been done in Germany, we don't know.
I don't know, first of all, and like it's sort of the
code of record essentially is based on, which really
has no experience in the United States, but we're
learning how to use it, and that's got a lot of models
built into it and has been benchmarked against some of
the tests that they've done in Germany.
We would hopefully use that data, disrupt
your test, but I think your point earlier is exactly
right. This is a research facility. In order to be
effective, it's got to be well instrumented, and that
is going to cost much more money than just building a
straight power plan.
MR. HOCKRITTER: That's right, and you'll
have conflicting objectives in the design of the plant
versus the measurements that you want to make. I
mean, that's the problem that LOFT had.
MS. HAUTER: Wenonah Hauter, public
Who should assume liability for this test?
How does Price Anderson play into this? What kind of
radiation releases is it appropriate to expose the
public to? And should there be a public process,
public hearings and so forth to determine if this is
something that the public would want to buy into?
DR. KADAK: Let me answer the last
question first. I think clearly the public has to buy
into this process, and relative to the public
hearings, you know, I'm not all that familiar with how
that would occur, but my sense is it would have a
licensing proceeding, but it would be a licensing
proceeding, licensed and experimental facility, and if
successful, probably another licensing facility, say
it's ready for operation.
The Price Anderson question, I'm not an
expert on Price Anderson, but, you know, depending
upon who ultimately ends up being the builder, whether
it's the DOE or some private government partnership,
those people would obviously have to pay the insurance
costs for that.
In terms of releases, again, you would
design the test such that they would be essentially
DR. POWERS: On the other hand, we could
test the validity of our consequence code.
DR. KADAK: That's on your nickel.
DR. SLABBER: Mr. Chairman, just Johan
Just a comment in support. I'm not
claiming and proposing that part of the PBMR
demonstration unit in South Africa will be used as
part supplying all of the information to Andy Kadak,
but part of our objective as a demo. unit, and it's
not a prototype; it's a demonstration unit; it will be
instrumented to such an extent that critical
parameters during transience, like load rejection, may
be loss of coolant, could be measured, and this is not
making an open statement.
We've got quite a good technological base
for proposing something like this because in an AVR,
they have done loss of coolant simulations, as well as
reactivity excursion experiments. It is documented,
and they found, and this is, again, coming back to the
integrity and the quality of the few, that they did
not observe any significant increase in releases,
although the core was filled with fuel, with a
variable degree of quality and burn-ups, and they've
also substantiated the reactivity predictions, the
temperature coefficient predictions.
So, in fact, there is a base where we can
stand on to claim that some of the tests that are
proposed in such a reactor has got some supporting
evidence in Germany.
DR. KADAK: Just as a follow-up, to the
extent that it's appropriate and doable, I think many
of these tests could be done on the south African
demonstration facility. So the concept is a generic
concept suitable for, I believe, any type of advanced
reactor that has certain characteristics.
CHAIRMAN KRESS: I'll take one more
question, Larry, and then we need to move on.
MR. HOCKRITTER: One of the things that we
dealt with a lot in the AP 600 was looking at
uncertainty, uncertainty in the predictions,
uncertainty in the analysis. Do you know if they've
done that with these code for the pebble bed in
DR. KADAK: I don't know. Perhaps Johan
knows better, but I have not been able to get at some
of the qualifications.
MR. HOCKRITTER: I know our class also
looked for that type of information, and we weren't
able to find that either.
CHAIRMAN KRESS: That's a good comment,
Larry, because I think having pinned down the
uncertainties in, for example, you fission product
release models is key to whether or not you really
need a strong containment or weaker containment, and
it has to do with how certain you are in your risk
So I think it was a really good comment.
So with that --
DR. KADAK: Could I just make one final
CHAIRMAN KRESS: Yeah, go ahead.
DR. KADAK: I don't think we should get
hung up on the fact that we're putting this
containment on a research facility as implying that
you need one. Again, the purpose is to show that the
fuel and the performance of the plan is such that you
don't need it. End the debate.
CHAIRMAN KRESS: Okay. With that, let's
move on to the next part of the agenda.
DR. POWERS: Mr. Chairman.
CHAIRMAN KRESS: Yes.
DR. POWERS: I notice that Sandia National
Laboratories may be some partner in this presentation.
I'm not familiar with this particular work, but
sometimes I associate with people from that
laboratory, and so members should discount anything I
have to say.
CHAIRMAN KRESS: We usually do anyway.
DR. POWERS: I noticed that.
CHAIRMAN KRESS: And I don't see why
anybody would associate with people from that
DR. APOSTOLAKIS: And, Mr. Chairman, I
have a direct conflict of interest here. So you will
have to do without me.
CHAIRMAN KRESS: You don't have to leave,
George. You can stay.
So thank you, Andy, and I don't know who
the next speaker is.
PARTICIPANT: I follow George.
CHAIRMAN KRESS: You follow George.
Okay. George, as I told everyone else,
you have to introduce yourself.
MR. DAVIS: Okay. My name is George Davis
I always like to start off with saying I
worked in the same place in Windsor, Connecticut for
about 28 years now, and I'm on my third company. We
started out as Combustion Engineering and then became
part of ABB and then last year became part of
Westinghouse, which is an indication of how the
industry is consolidating nowadays and how much things
I'm not really going to give today's
presentation. The meat of it is going to be given by
Mike Golay. Mike Golay is going to talk about what
we're looking at under a DOE NERI project, Nuclear
Energy Research Initiative, NERI program, looking at
the process for how one would go about applying risk
informed insights into not only deregulation, but the
design of your nuclear plants, such as Generation IV
But before Mike goes into that, I wanted
to first give you a little bit of a brief overview of
what we're looking at in a group of three projects
that includes this one all tied together.
Basically, a couple of years ago we put
together a team of industry labs and university
people. Besides ourselves from Westinghouse, we have
Duke Engineering from the industry side; Idaho
National Lab and Sandia; labs at MIT, N.C. State. In
fact, in one of the other projects we also have Penn
State that should be mentioned up here.
And then as we were looking at regulatory
issues, we even had a law firm, Egan & Associates, get
involved so we could bring in some of the insights
from Marty Mulsh to be here at the NRC.
What I wanted to do first is time to give
you an overview of where we see these three projects
that we're working on going in the long run and how
they fit together, and then introduce that as a lead-
in to Mike's presentation on the actual processes for
design and regulation.
The driving force for what we were looking
at in these projects was the issue of capital cost.
Basically when we step back and look at what we see as
the biggest challenges to nuclear plants being ordered
in a deregulated marketplace, we keep coming back to
capital cost as the big issue that we're having to
Production costs are looking pretty good
on the operating plants today. Fuel plus operating
maintenance are coming down. If you look at the best
performing plants, they're getting close to that one
cent per kilowatt hour production cost, and with the
consolidation going on in the industry and continued
improve, we don't think there's a whole lot of room
for continued improvement there compared to what you
can do on the capital side.
Secondly, there's the issue that with a
deregulated marketplace instead of taking 30 years to
pay back the mortgage on a plant, the investors in a
deregulated market are going to be looking for capital
costs to be paid back on a probably 20 year period or
less, which creates even more pressure to reduce
capital cost compared to what we saw with the old
regulated utility environment.
And so basically we come to the conclusion
that if we want to assure that nuclear can be
competitive against other alternatives, such as large
coal plants, where we see coal plant costs going,
we're looking at a need to reduce capital costs on the
order of about 35 percent or so below where we are
with a large ALWR, our System 80 Plus design.
If we want those to truly be competitive
against coal plants in the U.S. marketplace for the
long term, and that means we need to be looking at
overnight capital cost as a goal, somewhere around
$1,000 per kilowatt electric, and being able to get
these plants up and running in about a three year
So what we've done in these programs is
rather than tackle a particular reactor design, we
decided to step back and address the processes and ask
ourselves what can we do to improve the processes, the
tools that would be used for designing and licensing
future plants with Generation IV reactors that could
help to drive down the costs and cut a lot of fat out
of the process and provide designers with the
flexibility they need to be able to really come up
with new, innovative designs and get those licensed.
And so we have three projects that we're
working on. The first is looking at risk informed
assessment of regulatory and design requirements.
It's basically looking to develop methodology for how
designers would use PRA insights in the design process
in a much more radical approach than we've done in the
past and how that could also be translated into the
regulatory process for getting plants improved.
Next is the area of smart equipment, and
basically there we're looking at methodologies for how
you could put self-diagnostic, self-monitoring
features into plant equipment, such as pumps and
valves, as a way to improve reliability at the
All of this would obviously have some
benefits from an operating standpoint. The way we
think it would help on capital cost is if we can
address reliability at the component level. Then that
should allow us in the above-program on the risk
informed design process to step back and look at
simplifying on a system level.
In other words, if you can count on higher
reliability of the components you're using because of
these smart features built in, self-diagnostic, self-
monitoring features, then you should be able to look
at further simplification and not as much redundancy
being required at the system level if you can
encounter a more reliable components.
And in the third project we're looking at
are technologies that can be used for design,
fabrication, and construction of new plants, again, to
reduce the cost of those processes. And there we're
looking at what can be borrowed from the aerospace and
automotive industries and the approaches that they've
been developing over the recent years, again focusing
heavily on computer based application, to do things
like collaborative internet based engineering
We see that as being related to design of
regulatory process in the initial program, the top
program up there, because if you've got designs being
developed on an Internet based collaborative approach
like they're doing in the automotive and aerospace
industries today, then you could talk about in the
future getting to the point where the NRC and even the
public can have some limited degree of access.
You may have to have firewalls for
proprietary information in some areas, but the point
is you could have the whole design process a lot more
transparent and open where it could be looked at by
reviewers and the general public as the long-range
goal for where you're going.
So even the tools you used in the design
process could have some benefits for the regulatory
approach down the road.
MR. LEITCH: George.
MR. DAVIS: Yes.
MR. LEITCH: Regarding your second
project, I can see how smart equipment may improve the
reliability and safety, but I don't quite see how it
would improve capital costs. In fact, it would seem
to me just the opposite would be the case. Could you
run that past me again?
MR. DAVIS: For the individual component,
it would increase the capital cost of that component.
If you put in a smart valve, adding those monitoring
features and the computer software to go with it, it's
going to add to the cost of that valve.
However, let's say you've got in an ALWR
like our System 80 Plus. You've got a four train,
high pressure safety injection system. If you can
show high enough improvement in reliability and
individual components, you can go back and question do
I really need four trains of redundancy, if I can
count on the reliability of the individual components
in each system.
MR. LEITCH: That would be in a future
generation plant though.
MR. DAVIS: Yes, this is all looking down
the road at Generation IV type reactors. I mean, none
of these projects as I see it can lead to processes
that are going to be immediately available and can be
applied today. These are things that would be applied
down the road for Generation IV.
Now, we do see some potential that there
could be some spinoff applications along the way for
things like the pebble bed modular reactor, things
that might be developed for that, but these projects
were originally set up with the goal of developing
some very long range programs that would lead to
design activities of Gen. IV reactors in about ten
This figure, it looks like the cross-
section of a circular firing squad the way it's
pointed in, but the point here was that in looking at
how you risk inform the process, one could start out
at the very left side of the figure with the
deterministic requirement we have now and then looking
at those case by case, individually like we're doing
with the operating plants and asking where it can be
risk informed, those individual deterministic
At the other extreme on the right-hand
side, one could go to a more risk based approach where
you design based on the PRA, but recognizing that
state of the art PRAs are such that they're not
perfect and there are uncertainties not only in the
techniques, but in the database for PRAs, that you're
going to have to back up and add some degree of
deterministic requirements in to make the process work
to cover those uncertainties in PRA capabilities.
We basically started out in this project
thinking that we would start on the left side and work
across, but we quickly got to the conclusion that the
only way we're going to be able to come up with a
revolutionary new approach is for designing and
licensing plants that were going to allow some
substantial cost savings, was if we went to something
more revolutionary, where we went to a more risk based
approach and then back up to decide what needs to be
And that's a good example, I think of
where having labs, university, and industry working
together has been a good synergy, because from an
industry standpoint, we started off thinking in the
box on the left side, and the input we got from the
lab university people really caused us to step outside
the box and think more revolutionary on how we needed
to go with this, starting with the right-hand side of
Basically, as far as these projects are
concerned, because they're rather limited funding,
they'll wrap up next year. They're just intended to
lay a framework or a foundation for where we would see
these methodologies going.
The ultimate implementation of these is
going to depend upon several things happening. One is
we're starting to coordinate our effort with NEI. As
you'll hear from Adrian Heymer later this afternoon,
I believe, he's going to talk about NEI's effort, that
they're cranking up a task force to look at developing
a risk informed framework for further plants.
And it's our intent to coordinate what
we're doing in our project with them, but we'll have
a representative on their task force, and the goal
would be to make sure that what we do in our project
gets folded into what they're thinking about in that
task force and that we come up with consistent
results. They may not have to match up exactly, but
we obviously would like to try and have some
Very importantly, I think we want to wind
up in a situation where the technology road map
activities for the Generation IV reactors, that road
map that's being developed, needs to think about not
just developing new designs, but developing processes
to be used in designing and licensing those Generation
IV reactors, too.
So we're hoping that what we do in laying
the foundation for these engineering projects get
reflected in the thinking for the Gen. IV road mapping
effort so that there's some consideration of
processing as well.
I might also add as a final point I've
also participated in an IEA activity where they're
putting out a technical document later this year on
optimizing technology for water cooled reactors.
Although it says water cooled reactors, it's really
applicable to all three reactors, and it will embody
a lot of the same philosophies that we're looking at
in the engineering project.
With that I'll turn it over to Mike to go
into the discussion on what we're looking at in this
DR. GOLAY: Thank you, George.
Could we go to the next slide, please?
I'm going to speak about the specific work
that has come out of the regulatorily oriented process
among the three that George described, and I'm
reporting on behalf of the overall project and
particularly of the team from MIT, Sandia, and
Westinghouse, where the most active members are listed
here. Half of that team is in the room, and so if you
want to follow up after this meeting and discuss
things with them, they'll be available to do it.
Go to the next slide.
The thing that we have been focusing on is
really to try to create a comprehensive regulatory
approach that comes up with a method which is both
comprehensive and systematically consistent logically
and can be expected to create incentives such that
designers will naturally have reasons to do the things
which regulators recognize as being important in
coming up with good technologies.
So we've looked at it from the point of
view of an overall system to produce electricity
successfully where the designer's task is really in
both areas, and today we're going to focus on the part
having to do with safe production, but we recognize
that the designer has to produce an economically
attractive plant and hopefully corresponding to some
of the goals that Neil Todreas outlined earlier in the
So the focus here is going to be over on
safe production, but we want to have the incentives
aligned so that you achieve both of these and do a
good job on safety.
What I want to do is begin by posing two
questions to the ACRS, and that is fundamentally the
issue, I think, for the NRC is what do you do in terms
of regulatory reform. The fact that this session is
being held is a recognition that the current process
The fact that every new applicant for a
new reactor concept comes in where a part of his
proposal is a new regulatory treatment is, again, a
symptom of the need to improve things, and so the
issue is not whether improvement is needed, but rather
what should be recommended by ACRS and what role
should NRC play in achieving the improvement.
My specific suggestion is that we need an
effort where the overall national effort for advanced
reactors includes a component of regulatory reform
with the NRC being involved, but I think realistically
given the funding situation that the NRC faces, it
probably is not in a position to take the lead.
But that's a question I'd like to ask the
ACRS to ponder, and if you feel like offering advice
to do so.
And the second thing I want to do is
outline then for you the kind of product that we have
been able to develop so far where essentially it's a
work in progress, where there are some ideas of how to
attack this problem that we'd like to present so that
to the degree that you accept them, they can begin to
soak in, and to the degree that you think we need to
reconsider things, we can get the benefit of your
Some of the fundamental ideas are listed
here, and they're somewhat revolutionary. The top one
is that the process of regulation is guided by
decisions which are made based upon the beliefs of the
decision makers, that is, the regulatory personnel.
This idea of beliefs as opposed to
evidence is very important because what we would like
to do is find a way so that those beliefs which
cumulate in the evaluation of a reactor concept and
how it's operated, that one way we can state this is
in a probabilistic format, essentially using for
continuous variables a probability density function as
a way of addressing the relative likelihoods of the
range of possible values that the evaluator thinks are
And that when we approach things in this
fashion, what you're naturally led to is that when we
try to formulate acceptance criteria, that we do it in
terms of expected performance and also associated
And Tom Kress already alluded to the idea
of making your acceptance decisions based at some
level of confidence, which would be an example of how
you might approach that.
DR. WALLIS: Your choice of words is
interesting. "Belief" tends to be associated with
yes/no, I believe, I don't believe, I believe in
nuclear power, I'm against it sort of thing.
DR. GOLAY: No, I'm not talking about
DR. WALLIS: I know you're saying it has
to be probabilistic. So I tend to agree with you.
It's just the choice of the word "belief" is a little
DR. GOLAY: Let me distinguish. I'm not
trying to speak about values, which perhaps is the
version of that term that you're honing in on, but
rather, in terms of the conclusions that an evaluator
will reach regarding the relative likelihoods of
CHAIRMAN KRESS: It's the Bayesian concept
DR. GOLAY: Exactly, exactly.
DR. WALLIS: A state of knowledge is
DR. GOLAY: Right, exactly, and so what
we're leading to is a formal statement of that in a
formalism that is scrutable by everyone, and what this
really flows from is a conclusion that the problem of
safety regulation is not one of expected performance,
but rather of treatment of uncertainties.
Now, I know this is probably not a novel
concept to the folks here, but if you look at
proposals that we have had for regulatory improvement,
they're almost always focused on what should be the
deterministic expected performance criterion, and then
how the things perform in terms of that, when, in
fact, the big problem is dealing with the associated
And what we've tried to do is turn the
problem around and make sure that uncertainty is
imbedded in what we do from the very beginning so that
it has prominence at the same level of expectation and
is handled in a formally explicit fashion.
So that's what's behind what I have there.
We go to the next page.
DR. WALLIS: This is an unfortunate term.
I mean, if you tell the public you're uncertain --
DR. GOLAY: Yes, and I frankly want to
separate the problem of public communication from
technological evaluation, and the reason is that I
think that I didn't really mean to get diverted on
this, but I have an answer for it, which is that I
think we have made a mistake among engineerings of
falling into engineer-speak where the idea in public
communication is that if I communicate in the
vocabulary which I feel is most valid and with which
I am most familiar, I can also be most effective, and
I submit that the task of public communication is not
one of communicating a message concerning how hardware
will perform, but it is focused on helping the public
in their search for who to trust for dealing with the
And so the format for what we're
presenting here is not amenable to public
communication, but the task that has to be
accomplished in successful communication is really a
different one of giving people a reason to trust that
you will make good decisions.
Now, that's my answer. Other people will
have other answers, but I'd like to separate the two.
Okay. On the approach which we have,
we're also stating that regulatory questions,
unanswered issues concerning license submittal or
licensee behavior and their acceptance criteria, if
we're going to use a probabilistic framework, then
these questions and criteria have to be stated in that
framework as well.
So what we do is really use a
probabilistic treatment as the integrating and
systematic basis of evaluating a submittal, but we
continue to use deterministic models, data, tests, all
of the tool kit of evidence that we've always used,
but use it to support the probabilistic presentation
and to try to incorporate all of the questions which
are relevant to successful performance into what is
essentially a much expanded PRA.
This would require that both the license
applicant, who right now has the burden of proof in
terms of evidence, and the regulatory staff in
parallel justify their decisions explicitly in this
This is partly in answer to Andy Kadak's
point about the bring me a rock syndrome, and that is
what we would do if you accept the approach which
we're suggesting is that the warm, fuzzy feeling and
the bring me a rock would be translated into state
your evidence in a probabilistic format that we're
suggesting here just as the licensee must do.
And as part of this, you're very quickly
led to the need for subjective judgment and
incorporating that into the overall process, which if
you think about it, we do today, but we don't do it
And the one use of the probabilistic
format is to provide a vehicle by which to state those
judgments and, again, make them scrutable and to
incorporate them formally into the answer upon which
you base your regulatory decision.
That is a subtle thing to do, and it
requires development of processes for capturing those
judgments. Today what we have are informal processes,
but we use them. You know, the ACRS is a good example
CHAIRMAN KRESS: I'm going to ask you my
standard question. In this type of regulatory
DR. GOLAY: Keep going.
CHAIRMAN KRESS: -- which I'm very taken
by, how do you see the words "defense in depth"
fitting into that?
DR. GOLAY: Fitting indirectly. I'll come
CHAIRMAN KRESS: Okay.
DR. GOLAY: Give me about five more
slides, and if I haven't answered it, ask me again.
CHAIRMAN KRESS: Okay.
DR. GOLAY: Okay, and because
disagreements in these evaluations are inevitable,
some process of resolution will be required, just as
today in the regulatory system we have an appeals
process, but it's formulated more looking at things in
a deterministic fashion. So we anticipate the need
Okay. You see this kind of hierarchy
structure going from high level safety goals down to
inspection requirements and things like that. We
would basically stay with this, but what we would do
is try to handle things, as I say, using PRA as the
integrating method and continuing to focus on the same
kinds of essential safety functions that you want to
So nothing has really changed in the
structure here, but the way you would go about trying
to show satisfactory performance is what we would
Could we go on?
CHAIRMAN KRESS: How would you deal with
the issue that Dana gets very concerned about, and
that is the PRAs are traditionally, the ones we have
now, very incomplete. They don't deal with shutdown
conditions very well. They don't include fires very
well, and seismic even is often not treated very well
in human -- would you incorporate those kinds of
missing ingredients into the uncertainty of
DR. GOLAY: Yes. Now, basically the way
you would incorporate them is through a statement of
the subjective judgment of those who have to assess
what practices --
CHAIRMAN KRESS: That's where your
subjective uncertainty comes into play.
DR. GOLAY: That's right. So where
objective evidence reaches its limits, then you have
to go to subjective, as we do today. We just don't
spell it out.
DR. POWERS: Let me ask a question.
You're going to expand the capability of PRA to carry
this out. One of the areas you're going to expand it
to carry it out is in the shutdown risk.
Now, I presume that you have a plant here
that you say is going to have some history, and during
that history it's going to have various kinds of
shutdowns, those that it planned, which is going to do
a variety of activities that are going to be quite
different, and it's going to have an occasional
And you can prognosticate all of those
things, all of the different configurations of the
plant that go on during a shutdown, a scheduled
shutdown for refueling and whatnot.
DR. GOLAY: I would say that your task in
those areas has not changed from the task that people
have today; that when you go to consider a license
application, you try to consider the spectrum of
conditions under which it will be operated, and using
evidence appropriate for each condition, judge whether
it will be operated successfully.
So that --
DR. POWERS: But now we don't try to
DR. GOLAY: That's right.
DR. POWERS: -- those times and
configurations, and yet you want us to do that. How
is this possible?
DR. GOLAY: Well, I think that the
development of shutdown risk analysis provides an
illustration of how you do that in, say, a non-power
state, and when you're comparing operations between
those states, you, as Tom just brought out, you
inevitably come to situations where the available
objective evidence is not sufficient for you to
determine, say, which practice is better.
Do you do maintenance while you're shut
down or do you do it on line, for example? And,
again, subjective judgment has to come into the
And what I'm submitting is that we use
that subjective judgment today. We simply don't spell
out loud the factors the way that we're weighing the
factors, and what's changed with the approach that
we're suggesting is that we state it in probabilistic
terms and incorporate it into the PRA.
CHAIRMAN KRESS: Let me expand on Dana's
question a little. What I'm interested in is the risk
associated over the full lifetime of the plant. That
means shutdown number 85 is going to take place n
years from now I need to incorporate into my risk
Now, since I don't know what that shutdown
consists of, what planned maintenance they're going to
have because it hasn't even come about yet, it may
even be an unplanned shutdown. How do I know how to
incorporate the short time during shutdown, short
compared to other things? That risk, how do I put
that risk component into my risk assessment when I
don't even know what it -- we're dealing with a
change, a variable configuration in time rather than
a fixed configuration, which is what PRAs usually deal
How do I deal with that in a PRA? Is that
something that needs a new PRA methodology for?
DR. GOLAY: I would submit not, but let me
go to why The first question that may arise is why do
you need research on regulatory reform. Why can't
you just get a few people to go off and think in the
corner for a time and come up with some proposals and
then try them out?
My experience has been that you don't know
what is a good idea until you've gone through some
feasibility attempts; that there's an iterative
process here, and that's the heart of doing that kind
of research, to find out what's feasible and then from
that find a good blend of feasible approaches
consistent with an over arching logical framework.
In terms of the question you've asked, I
would suspect, without having tried to do the analysis
you said, that, first of all, the level of detail
required is probably not necessary; that approaching
it from the point of view of looking at safety during
shutdown and trying to anticipate a range of
conditions that you think are reasonably plausible,
which is the approach we have today, I think that that
And what I would try and do is turn it
around and try and use a real probabilistic treatment
of the safety, but not to try and anticipate the fine
detail the history of a plant that might occur or
might not occur.
CHAIRMAN KRESS: You could use past
experience of what has occurred.
DR. GOLAY: That certainly would be part
CHAIRMAN KRESS: The database maybe.
DR. GOLAY: Yes, exactly, exactly.
Does that respond to what you brought up,
DR. POWERS: Yea, I was bringing it up for
DR. GOLAY: Okay. All right. Let's move
on or we're going to be here until four just on this
George showed this slide earlier, and
essentially where he said that we are in our work is
over on the right-hand side, which is taking a top-
down and probabilistically based approach, and it's in
complement to most of the other approaches that I've
seen, which are really trying to find an accommodation
with the existing approach, partly because they're
driven by the need to get a license.
You know, as people say, you don't drain
the swamp when you're to your rear in alligators, and
that tends to be the situation for most of these
projects, although I'm sure that many people are
thinking about the whole range of this.
But our starting point is over here, and
that's one way in which as far as we know, our work is
somewhat different from the others.
However, the elements that go into it are
the kind that you see always, which are that you want
to find a way to incorporate defense in depth and
safety margin. These are good design practices
regardless of the regulatory approach.
And one of the things that led us to the
suggestion we're making today is that we wanted a way
to state the benefit that you get from these various
DR. WALLIS: Do you have a good measure of
safety margin in a probabilistic sense?
DR. GOLAY: Yes. If you're using margin
on let us say approach to melting temperature or
something of that kind, what that would translate into
would be to formulate your acceptance criterion from
the design point of view at a very, very high
confidence level so that you insure -- and you, of
course, could say that let us say your 99 percent
level could be somewhat reduced from what you think is
the actual failure point, would be a way that you
would do that.
DR. WALLIS: But once you start saying
there's a failure point, you are making things
deterministic, which really are not.
DR. GOLAY: Well, I'm trying to relate it
to the current design process.
DR. WALLIS: That's right, but I think it
would be interesting to see what you could do with a
definition of margin which got away from these ideas
of having a point or --
DR. GOLAY: Right, and what you would do,
as you're hinting, is really to use a distribution on
all of the performance limits, and that would be a
natural evolution that I think we would go to and
probably quicker than I'm anticipating.
DR. WALLIS: You would look at the
probabilities of all of those and the consequences of
all of those.
DR. GOLAY: Right. That's right.
So what you expect is that if people are
using the approach we're suggesting well, they would
have natural incentives to put defense in depth into
their designs partly because they could see a benefit
for doing it when they go and make a regulatory
The same thing with margin.
CHAIRMAN KRESS: How do I decide what
confidence level constitutes an acceptable margin?
DR. GOLAY: My short answer is you have to
work on it.
DR. GOLAY: Well, it's partly a social
policy and has to be worked out with --
DR. POWERS: We've been working on it, by
the way --
DR. GOLAY: -- the regulator.
DR. POWERS: -- for four years that I know
CHAIRMAN KRESS: I'm glad you said that
because that's my belief also. It involves things
like the loss function, for example, in decision
DR. GOLAY: Right. And so if we're
successful in our work, what we will do is kind of set
some directions for future work to pursue because some
of these, as you know, are very subtle. But if we
accept the overall approach that we're trying to lay
out, that's the most important thing that we really
want to get across.
And then there is a lot of research for
professors to do, keeping lab personnel out of
CHAIRMAN KRESS: Yeah, we've got to keep
DR. GOLAY: Right. There you go. Well,
that's never been a problem.
Could we go to the next slide?
One of the other points that I want to
make is that we tried to come up with a regulatory
approach which would be useful at different conceptual
stages of development.
One of the things which I've observed
makes consideration of regulatory change, makes those
discussions difficult is that if you don't state the
level of maturity of the concept, what's approach
becomes a difficult conversation because what's
appropriate in one circumstance may not be in another.
But this notion that you're using a
combination of probabilistic analysis and essentially
your best set of probabilistic with deterministic test
experience and judgment at any stage of maturity is
the consistent part. And I'll come back to this in a
And the idea is that as the maturity of a
concept grows, that the level of detail and our
ability to introduce concepts that we're familiar with
from light water reactors, such as DBAs, design basis
accidents, that that will also grow, but that at an
early stage, some of this may not be applicable.
Can we go on?
So in this table, what we've tried to do
is put together an illustration of what we're talking
about in terms of different levels of maturity as we
go from an initial concept to the nth plant as we have
with light water reactors, where there are many of
them around and where we have a lot of experience
And basically the regulatory system gets
into it in the lower three rows of this figure, where
you may have an initial detailed design, but where
it's not feasible to do more than formulate the high
level acceptance criteria, and where our level of
detail in the knowledge of the system is also fairly
The idea that I want to get across is that
as we work our way down the figure and later into
time, that the amount of detail, the number of finely
crafted performance goals that you can come up with,
and your ability to translate those into deterministic
decision rules will tend to grow, but in the early
stages, you tend to stay high level and mostly
DR. WALLIS: It's an interesting idea, but
it seems to me that as you learn more about a plant,
you might actually get less detail than any kind of
plan. You might really know what you have to worry
about and you don't need all of this detail.
DR. GOLAY: Conceivably, and we've seen
that, for example. I would say that the evolution of
the passively based water cooled reactors could be an
illustration of that.
But one reason for putting this figure
together is to address this question of where does the
design basis accidents and general design criteria
come into the picture here, and I would say it's a
tentative conclusion, not a firm one, that those
really play a role when you get to the detailed design
and later stages of things because when you try to
formulate design basis accidents, you have to have a
design. You have to have a concept in which to think
about and have some seasoning in terms of your
understanding of its weaknesses, things of that kind.
And if you look at what we've done with
light water reactors, we've gone through the evolution
shown here, but with not quite knowing it or not
saying it out loud, and especially the reason I've put
this up concerns general design criteria.
That is, if you look at the general design
criteria that we have for light water reactors today,
most of them are motherhood statements. They're
essentially do good things, put in margin, put in
conservatism, defense in depth, and so on.
There are a few things like have a
containment, have redundant shutdown systems, which
are spelled out, but most of the criteria are not, and
they're formulated in a way which reflects what's
feasible, mostly driven by light water reactor.
And one idea which we think is worth
exploring is whether that the formulation of GDCs
should be done at a concept specific basis, reflecting
some accumulation of study and experience.
And it bears on the question, for example,
of whether you need a containment for the gas cooled
reactors, and I'm not going to offer an answer for it.
I'm just suggesting that with this framework, you
might delay trying to answer that question until
you've gone through some evaluation in this as opposed
to starting by, you know, God said you have to have
containments, and then from that we go on to other
DR. POWERS: And He did.
DR. GOLAY: Or She.
DR. GOLAY: Okay. Can we go on?
The other point I want to make is that
there's nothing in what we've prepared which is
inconsistent with the cornerstones, with the approach
that the NRC has been taking in terms of restructuring
the emphasis in the design and regulatory concerns.
What we have focused on in our work on
examples is over here in the reactor safety part of
the structure, but when we've looked at it, we don't
see anything that would stop you from going to the
other issues. We just haven't had the resources to
work on them.
Can we go on?
And in terms of setting performance goals,
what we've done, this is an illustration of a master
logic diagram to help you identify initiating events
that would be important in your event sequences or
your accident sequences, as Andy Kadak had suggested,
replacing the design basis accidents by the risk
dominant event sequences has some attraction.
And what we've concluded is that you
really have to break this into two parts. One is a
general treatment at a very high level where you have
certain performance goals, and as we go down in the
hierarchy here of this fault tree, going to finer and
more finely defined events or the concatenation into
creating a public threat, that there's a general level
at which you can set performance goals and where the
safety goals are examples of that, and then below
that, when the details of the concept become
important. The kinds of failures that you worry about
and the combinations of events then will be concept
And so we're seeing a two-step way of
approaching the fault tree and from that the master
logic diagram and eventually the initiating events,
which are of primary importance.
So, for example, what's in the handout
figure is kind of our first shot at how you would draw
this for a gas cooled reactor. It's by no means
complete or even correct in every detail, but the
purpose is to illustrate how some of the initiating
events and failure modes that show up are not those
which show up for water cooled reactors.
For example, one of the things in here is
failure of the radiative cooling path, which in the
water cooled reactors we don't even worry about. I
mean, when you think about it, this becomes obvious,
but it's an illustration of how you would go about
Okay. Could we go on?
How much time do I have, Mr. Chairman?
CHAIRMAN KRESS: We are supposed to -- you
have about 15 minutes more.
DR. GOLAY: Okay. Keep going. I'm going
to skip over the next, I think, three. Right. Stop
Okay. The last thing that I want to move
to is interaction between the applicant and the
regulator, and what are the implications for the
approach that we're suggesting?
And what we're really focusing on is that
when you have an applicant come in with, let's say, a
new reactor design application, what they do, they
submit all of their documentation, of course. They go
through review under the standard review plan, and all
of that is preliminary to what is a negotiation
between the licensee and the applicant regarding
what's acceptable or unacceptable about the design,
and then it's up to the applicant to find a way to
satisfy the regulator.
We expect that that process would
continue, but that it would be replaced. Today it is
really focused around how will systems do concerning
design basis events with consideration being given to
evidence from things like the PRA and treatments of
uncertainty and so on, but the DBA has played a
central role in the way things have been structured.
What we would do is reverse that and have
the probabilistic integration of the system
performance be the primary vehicle used for the
evaluation, but the much more comprehensive version
spoken about, and that the acceptability negotiation
would be conducted in the context of the RPA, where we
would need consistent procedures, tools, and
termination criteria for this negotiation process.
That's for reviewing new designs. We
anticipate that for the regulation of construction and
the regulation of operations, that formulation of a
set of deterministic rules, but based upon risk based
information could be done, and we think that that's
desirable for practical reasons, for people in a
construction site. You don't want them running PRAs
all the time and making decisions.
But we're suggesting that if the review of
the new design, that it is a practical thing to
undertake today, particularly when you're looking at
marginal changes in the performance.
Okay. Can we go on?
And so I want to give an illustration of
how this negotiation or discussion might proceed,
where the idea is that initially a designer would come
up with a plant design satisfying the goals of that
first figure that I showed, producing economical and
safe electric power, and that it's his or her
responsibility to come up with a design that will do
that very well.
When the designer, design team, more
realistically, thinks that they have satisfied the
performance goals that have been formulated by the
regulator, they submit their application and it's
Presumably there will be some areas of
disagreement regarding the adequacy of the submittal
because that tends to be the nature of the licensing
process. However, what we're expecting is that the
disagreements should be in terms of the expected
performance, safety features, the performance criteria
that were used internally to decide that they would do
well, and the methods and analysis, that is, the data
and models used, and that this process be documented,
again, in the probabilistic terms.
Can we go on? We seem to have lost
something here. Yes.
DR. WALLIS: Let's try to think about
this. The method of design and analysis is going to
be in probabilistic terms. You mean that every time
you put a correlation in a code, you have to do
something probabilistic with it?
DR. GOLAY: Only if it propagated through
into your risk evaluation.
DR. WALLIS: It probably does.
DR. GOLAY: Yeah. For example, if your
new correlation had a different uncertainty treatment,
you would expect that to be propagated through, yeah.
Okay. Can we go to the next one? This
one isn't coming through, but what it's meant to
illustrate, I'll tell you what you would be seeing if
it were showing up, which is above the line showing an
iterative risk based design process, and below the
design, showing an iterative risk based review and
feedback of that process.
So below the line we're dealing with the
negotiation between the designer and the regulator.
Above the line, we're dealing with the designer trying
to do a good job in the first place.
Ah, there we go. Okay.
And hopefully when they've gone through
this, they will eventually reach satisfaction on the
acceptance criteria and gain a license.
Okay. Let's go on. Oh, no, not another
one. That's the same one. Is there any way to turn
this off and move ahead?
DR. APOSTOLAKIS: It was too fancy.
DR. GOLAY: Yeah, I can see that. I can
And this is what we foresee that the
designer would be doing, and that is -- and I'm going
to give you an illustration of this, which is start
off with what we call the bare bones design, and this
is only an illustration of how we think it might
proceed. This isn't a requirement for anybody to do,
but essentially create a design to produce
electricity, and then go through and ask: well, what
are initiating events which could cause a safety
And it doesn't just have to be core
damage. It would be in all the cornerstones.
To use a PRA to identify the dominant risk
contributors, and from that to identify mitigative
features and systems that could be used to alter that
PRA profile and iterate on this until finally the
design comes to satisfy a vector of acceptance
criteria, which would be formulated at whatever is the
right level for maturity.
DR. WALLIS: Couldn't there be a scaler
that says that whatever your PRA produces must be less
than some number?
DR. GOLAY: Within a certain area of
performance, that would be the case, but we recognize
that there will be many areas of performance.
For example, you may want to have the
frequency of initiating events to be very low,
satisfying one of the cornerstones, and you may also
want to have a very low core damage frequency, as well
as a very low frequency of activation of the off-site
So, in general, we're anticipating a
vector, but each element would be stated in
deterministic terms, and so this is what the designer
would be going through before the submittal and then
afterward, following the negotiation.
Okay. Can we go on?
One of the things which we want to get
across is, and this figure doesn't do such a great job
of it, is that the formulation of the acceptance
criteria, once you go below that line of concept
specific performance criteria, has to be determined
iteratively because how you divide what's acceptable
in a high level performance goals into a set of
subgoals depends on what's feasible.
And so, for example, I want to use the
example of for a light water reactor LOCAs of
Where when we went through with the
Westinghouse design team for the set of very small
LOCAs, small LOCAs, and large LOCAs with a particular
mitigative system, what we ended up with is this array
of core damage frequency, where you see it's a non-
uniform distribution, and that's the key point we want
to get across in this illustration.
So that as you take the overall division
of what's acceptable ways of having core damage, that
you wouldn't necessarily divide them up uniformly
among all of the categories of such events.
And that's a reflection of what we are
trying to talk about when we say you have to do some
work to see what is feasible to do, and the answers
will be different from one concept to another.
DR. POWERS: When I look at this table,
I'm not sure what numbers I'm looking at.
DR. GOLAY: Well, it's the right-most
column that I really want you to --
DR. POWERS: Yeah, I know, but I want to
get to that right-most column. Are these -- am I
looking at products and means or something else?
DR. GOLAY: Means. These are for purposes
DR. POWERS: So mean time a mean equals a
mean? I don't think so.
DR. GOLAY: Yeah, I think for purposes of
what we're talking about, but if you want to do it as
the integrated result to the stated confidence level,
we can do it just as well.
The key point that I really want to get
across is that you can't simply sit in your office and
decide, well, I'll slice up the risk pie in, let us
say, a uniform way or some way that I particularly
like; that it's always a compromise between what's
feasible and what's desirable, where I would say
what's most desirable would be to try to spread the
risk among sequences as much as you can or not put
your eggs in one basket, but for various physical
reasons, your ability to do that may be strained.
DR. WALLIS: Why do you need subgoals? It
seems to me that if you had a plant that had no LOCA
probability at all because of its design, then you
might trade this off and be allowed to have more
probability somewhere else if something else and all
you care about is the total.
DR. GOLAY: But you care about the
uncertainty associated with the total as well.
DR. WALLIS: Yes, you do, but the total,
the bottom line is the thing, not really how it breaks
up in all these pieces.
DR. GOLAY: Yeah. Well, I would say that
another reason why you want to do this is that in the
long run for regulatory convenience and efficiency,
you probably want to move -- try to find risk-based
deterministic decision rules as you reach a high stage
of maturity, and so there will be sort of natural
incentives to formulate subgoals as the concept
And that's the reason we have this in
here, simply to illustrate that you have to go through
this iterative process. It's not to carry it further
than that. Okay?
CHAIRMAN KRESS: Would there be a guiding
principle on how to -- this is more or less talking
about rationing the risk among the various --
DR. GOLAY: Right.
CHAIRMAN KRESS: -- as a defense in depth
concept. One does this because he's uncertain about
each of these results.
DR. GOLAY: Right.
CHAIRMAN KRESS: And so he wants to spread
that uncertainty out, but is there some guiding
principle one could come up with that says that that
uncertainty, overall uncertainty, ought to be either
minimized by selecting these distributions to optimize
the level of uncertainty of each one so that it's
minimized at the end, or so that it's acceptable, or
is there a guiding principle on how to make this
allocation of risk?
That's what --
DR. GOLAY: I think we have to do some
work on it before we really know the answer to your
question. My suspicion is that we want to go in the
directions that you're saying, which is to try to make
the distribution reasonably uniform and the total
small at whatever your stated confidence level is.
But I'm sure it's more subtle than that.
CHAIRMAN KRESS: There has to be some
other principle that tells you how to do this.
DR. GOLAY: Exactly. And what I'm
suggesting is the principle is really one of trial and
error to see what it is that's feasible to do.
CHAIRMAN KRESS: And, of course, that
would enter into it.
DR. GOLAY: Yeah, and I'm doing this
because the message I want to get across is that
formulating a practical system that people can really
use takes some work, takes some sustained resources
and is sometimes pretty subtle.
Okay. Can we go on?
So I want to go through how we did this,
our team, concerning dealing with LOCA events where we
came up with an improved system over the -- this is
for light water reactor system.
Started off with a bare bones system and
then from that added in some mitigative active
systems. So I'm not suggesting this is the best
design you would want to use, but it's one that's
consistent with the active light water reactors, such
as we have.
And so we have two high pressure injection
systems, one low pressure system. I won't read all of
this to you, but essentially some of the usual
candidates, passive DC power, shared chemical and
volume control system.
And from this, our designers contended
that they had an acceptable design.
Can we go on?
And so what we're foreseeing for this
negotiation is a process outlined, is in the flow
chart on the next figure, where the applicant thinks
he's done an adequate job and makes the submittal.
Upon review, the regulator says it's not adequate
basically because of a dispute concerning modeling
assumptions, which could be resolved by getting better
data, and the reason is that the core damage frequency
associated with the high pressure category of LOCA is
seen to be too great.
One way that it could be solved is to have
a research program, go out and get more data. Instead
the designer decides to alter the design, and what he
does is go and decide he wants to make the response to
high pressure LOCA be one of depressurization, and so
he does this by putting in a train of depressurization
capability in his shop, not going back to the
The result is that the core damage
frequency is still too high. That is, we have an
acceptance criterion in terms of the core damage
frequency or LOCA.
And so in the next iteration, the designer
comes, and he puts in an additional train of
depressurization capability, still finds that it's too
high, and the reasons upon investigation are that
common cause failures involving the cooling system and
the emergency diesels are too high.
Could we go on?
CHAIRMAN KRESS: Now, go through this
process. I have to have in mind a CDF that's
acceptable for just LOCAs.
DR. GOLAY: Yes.
CHAIRMAN KRESS: Or for LOCAs of different
sizes, which is kind of a tough number to come by.
You know, I've got an overall CDF in mind, but I don't
know how to fractionate that up among LOCAs and other
DR. GOLAY: Right, but what we're
anticipating is --
DR. POWERS: Why don't you just do it?
DR. GOLAY: Now, we're not saying how the
number was gotten at. We just want to illustrate how
the process would go forward, and if such a criterion
were to be formulated, this is how we would expect it
to be tested on whether it's acceptable.
In the very early stages, I think you'd
have trouble formulating that. In the later stages of
maturity, you might be able to.
CHAIRMAN KRESS: Somewhere along the line
we've got this.
DR. GOLAY: Right.
DR. POWERS: Why would you want to wring
your hands over it? Why not just say, as is
apparently done here, "I don't want it above two times
ten to the minus sixth on a LOCA"? Which one is more
capricious and arbitrary?
CHAIRMAN KRESS: It might very well be
that my overall CDF goal is, say, ten to the minus
five, and nothing contributes to that except the LOCA,
and I might very well be willing to accept it as ten
to the minus five. That's the confidence level.
DR. POWERS: You might well be willing to
after the fact change things, but if you're just going
through this exercise here that he's outlined, --
CHAIRMAN KRESS: You're saying you don't
need the -- when you look at the whole system in total
and make some judgmental --
DR. POWERS: Yeah, I think you can.
DR. GOLAY: I think that may be a
reasonable process, too.
DR. SHACK: Well, it's a question of who's
setting these numbers. The designer can set it any
way he wants to, and the question is whether the
regulator then forces those numbers.
CHAIRMAN KRESS: Well, my point was should
the regulator come in at this point and have
acceptance criteria related at this low a level or
should he just focus on the endpoint?
And I think, you know, that that's the
DR. POWERS: Sure.
CHAIRMAN KRESS: Should you focus on the
endpoint or should you come in at this point on the
DR. POWERS: It is what point you come
CHAIRMAN KRESS: Yeah.
DR. POWERS: We know that they will come
in more than at the endpoint.
CHAIRMAN KRESS: And that's why I keep
harping on defense in depth. this is a defense in
depth concept, whereas if you just focused on the
endpoint, perhaps it's not.
DR. POWERS: Right.
CHAIRMAN KRESS: And this may be a way to
bring in defense of depth or it may not. I don't
DR. GOLAY: Well, that's actually part of
why we picked this illustration, because we're
anticipating that as the maturity grows, there will be
a natural evolution of performance goals formulated at
a lower level.
For one thing, it makes the design process
more efficient and should make the review process more
efficient, but that's why also I went through this
business that where you set the goal depends on the
maturity of the concept. There isn't just one answer.
But we're assuming that things are mature
enough that we can work at the system level with
system specific or relevant goals, and so the idea is
that after rejection, the designer goes back and using
the kind of risk information we're showing here, keeps
modifying his design until he thinks that he's got
something ready for another path.
Could we go to the next figure?
Upon submittal, there are two paths that
we consider to be worth thinking about. One is the
easy one down here, is Evaluation 2, which is that the
performance goal is met.
The second may be that, let us say, when
you're trying out a new lower level performance goal,
you may find that satisfying it is pretty difficult in
terms of cost-benefit tradeoffs, and that you might do
a better job at meeting your higher level goal by some
So we see both approaches as being
feasible, depending on the level of maturity of the
concept. But for today we're going to take it that
he's trying to meet the standard, and we'll talk about
how to do that.
Okay. Could we go on?
Now, this is a table of how in our risk
assessment the core damage due to LOCA, core damage
frequency, changed, and we're listing here the median,
the five percent, 95 percent, and also what we're
calling the risk metric, and that is one of the ideas
I want to get across in here is that we can consider
uncertainty just as easily as we can expected
And so we are taking the postulated
situation that the NRC has said that the acceptable
risk metric will be one involving 75 percent of the
median core damage frequency and 25 percent of the 95
percent core damage frequency and requiring it to be
less than seven times ten to the minus seven.
This is just as an illustration of how you
might try to take uncertainty into account in an
explicit regulatory acceptance criterion.
And the point is that if you look at the
various entries here, what you see is that as we go
from the initial no depressurization capability down
through the different design iterations, that only
until we get down to two train depressurization with
an improved treatment of cooling water and diesel
failure do you satisfy that acceptance criterion in
terms of this risk metric.
But there's nothing harder about
formulating a criterion involving uncertainty measures
than formulating one which is strictly deterministic
as we do today, or in terms of expected performance.
The trick is to make sure that the
distributions that you're using reflect reality as
well as you can, and if you do that and propagate
these uncertainties, you should be able to get useful
answers, just the ones we want you to think about.
CHAIRMAN KRESS: How is this, the first
metric that you selected, any different than just
specifying a confidence level?
DR. GOLAY: We felt we could have done it
at, let us say, a 75 percent confidence level. We
felt that in reality that when people think about it,
what they do is think about the expected performance,
and they try to put on some margin factor for
uncertainty, and we thought this was a way of trying
to capture that.
CHAIRMAN KRESS: It fits into that.
DR. GOLAY: But how you do it is, again,
some thing that there are different approaches for it.
The main thing I want to get across is that it's very
easy to incorporate treatments of uncertainty, as well
as expected performance here, and given that
regulations about uncertainty, we think that this is
a big contribution, at least potentially.
Could we go to the next figure? Other
Okay, and this is just a graphic of the
same change in the core damage frequency at different
confidence levels, including this risk metric. The
blue one is the risk metric that we were using, and
you see that it could play the role just the way that
evaluation at a conservative confidence level could
So what's the best treatment would be for
future work, but if you accept that the idea is worth
exploring, that is a step forward.
Let's go on.
Okay. We're almost at the end. Lunch is
The point is in this example what we tried
to show is how that we can have a natural way for
concern about common cause failures and uncertainties
to lead designers to incorporate some defense in
depth, some use of safety margin, to show how we can
take uncertainty into account in evaluating
acceptance, and that the bottom line is really the one
that is most important, and it addresses what you need
to pay attention to in future research, which is that
there are a lot of practical questions that need
examination here, and to answer them you need trial
examples, such as we just showed you.
You need some work to come up with
standardized models, methods, and databases which are
much more capable than those which we have today.
And one of the areas which we really
haven't explored -- by "we" I mean everybody in this
room -- very much, but which is quite important, is
methods for treating subjective judgment, for
incorporating it into the decision making process in
a more formal way.
We suggest that through this process, we
may be able to replace the need for general design
criteria and DBAs, and we would probably have to alter
the standard review plan in important ways.
So these are all practical problems that
need to be investigated.
Can we go to the last slide?
So in summary, what I hope you've gotten
is an understanding of a new design and regulatory
process that we propose for development. It's risk
based. It incorporates defense in depth and margin.
We think it would provide a more rational and
consistent method regarding both design and regulatory
It provides a method of integrated
assessment which we currently lack except in the
treatment probabilistically in the background of the
process we have now, and it should be applicable to
non-light water reactor technologies in a
straightforward fashion just as to light water
So in effect, the implicit favoritism
which our current process bestows upon light water
concepts could be removed through this and hopefully
would lead us to somewhat better technological
And we feel that the development of this
process should be supported as part of our overall
attack on developing new technology, and that's all I
have to say.
CHAIRMAN KRESS: Okay. Are there
questions or comments?
DR. POWERS: I guess the thing that comes
most immediately to mind is actually on his first
bullet there, where he says defense in depth when
necessary to address model and data uncertainties.
Don't we do a defense in depth for other reasons?
CHAIRMAN KRESS: Pardon?
DR. POWERS: Don't we do a defense in
depth for other reasons?
CHAIRMAN KRESS: Yes, there are other
reasons for it, I think. What reasons would you have
DR. POWERS: I guess two things come to
mind, one of which you might put in the category of
model uncertainty is, well, we don't account for
sabotage in the PRAs. I'd just as soon have some
protection against a plausible threat to the plan.
The other one is in your probabilistic
studies you always come up with some probability of
bad things happening. Just between you and me and the
gate post, I'd like to have something between me and
the bad stuff when those bad things happen, regardless
of how infrequently they occur.
DR. GOLAY: Is that a question?
CHAIRMAN KRESS: It's a comment more than
DR. POWERS: He asked for comments.
CHAIRMAN KRESS: If you want to respond,
DR. GOLAY: Yeah, I will, and that is
concerning your example of security, I don't know. I
haven't worked on security, and I don't know how you
might try to handle it here.
My first reaction is: why not try? I
don't know of anything that would preclude you from
being able to include that successfully, and what I
would like to do is sort of turn the burden around and
make a presumption that we can handle the questions in
a probabilistic framework until we have clear evidence
Fundamentally you said that reason for
defense in depth was not wholly treatment of
uncertainty. Yet the examples you brought up were
essentially treatment of uncertainty examples, and if
you think that a practice is beneficial in terms of
getting a good safety result as a response to
uncertainty, then you should be able to state it,
state your belief concerning that fact in a
So it's not disagreeing about the value of
defense in depth. I'm simply saying it's worth the
try to incorporate anything that you think is
important to the answer in the format.
MR. HOCKRITTER: Larry Hockritter, Penn
On page 10, you talk about using best
estimate performance, expectations and uncertainties.
And you really have two kinds of uncertainties. You
can have the plant uncertainties, but you can have the
uncertainties in the model that you use to do the
predictions, and with a light water reactor, we've got
40 years of a database, experimental database so that
we can quantify the models and the model uncertainty
so that we have a good handle on that.
I don't know how you address that for a
new design like we've been talking about for these
Gen. IV designs where you really don't have much of a
database at all.
So that's one question.
DR. GOLAY: Should I answer?
MR. HOCKRITTER: That was a question.
DR. GOLAY: Yeah, with any concept,
regardless of its level of maturity, I'll submit that
as you try to do a risk analysis of comparing
alternatives, let's say, that you ultimately end up at
a point where the available objective data reach the
limits, and you can find this with plenty of light
water examples as well, that what you're really into
is a situation where you -- I think always -- that's
too strong a word because I don't have the basis for
saying "always," but my experience has been so -- that
you end up with a combination of objectively based
evidence and you have to supplement that by your
And so the only suggestion that we're
making is that you should state that in probabilistic
terms and incorporate it into the PRA so that with the
new concept, you reach that limit much sooner than
with the mature one, but that the general structure
holds up for both.
MR. HOCKRITTER: Okay. Well, I can now
turn the question around and say if you would embark
on this type of a licensing process, you could use
this approach to structure the types of test programs
that you would need --
DR. GOLAY: Absolutely.
MR. HOCKRITTER: -- for a Gen. IV type
plant. So I see a real benefit in that.
And then just one other comment. The
examples that you showed, the design examples, I know
on the AP 600 we did use that process where we went
through the PRA. We looked at the performance of the
systems and the system sizes in this case changed.
DR. GOLAY: Yeah, and what was lacking in
that example is the regulator being prepared to engage
you in the same vocabulary for making their decision.
MR. HOCKRITTER: There was never a problem
with the regulator engaging us.
CHAIRMAN KRESS: Go ahead.
MR. PARME: Larry Parme, General Atomics.
I have a question in regards to your last
page or near there. You mentioned possibly replacing
the DBAs with the risk dominant events, and overall
I'm supportive of your approach, but in the licensing
approach risk based that we did for the MHTGR, one of
the -- we were looking at that sort of approach, and
we immediately ran into the problem that when you go
and say that the risk dominant events replace DBAs,
you find that certain non-risk dominant events are the
only challenges, if you will, to certain key equipment
or safety functions, and the risk dominant events may
not demonstrate to the regulator the various ways that
your safety functions are done.
And I hope you follow what I'm saying. My
question to you is: did you think about this?
We had thought about this in the '80s,
found that risk dominant events weren't a true
substitute for DBAs and had to also use the PRA, but
had to find -- pull from our event trees events that
challenged each of the safety functions regardless of
their risk dominance.
DR. GOLAY: Right. Let me try and
translate it though, and that is what I think you're
really saying is that there's a concern about the
level of uncertainty associated with your risk based
analysis, such that if you went in and claimed that
you were doing very, very well, it wouldn't be a
credible claim, and that it was necessary to, in
effect, show that you could handle something tougher
is in some way a defense in depth kind of capability.
CHAIRMAN KRESS: I would have put that a
little differently. I would say that there are
regulatory objectives that are more than just CDF,
LERF, BES (phonetic) --
DR. GOLAY: Sure.
CHAIRMAN KRESS: -- ANDERS (phonetic), and
those regulatory objectives can be captured.
And you had one little box called FC
curves. If you actually had acceptance criteria on
those, I think it would capture these things that
you're talking about that don't have much to do with
LERF or probable fatalities, but how to function in
being sure that you don't have smaller releases or
worker exposure and that sort of stuff, which can be
captured in F-C curves.
DR. GOLAY: That's a good point, and I was
taking for granted that the cornerstones had all been
addressed, which in that era they were not.
CHAIRMAN KRESS: Yeah. I hate to do this
because I think this has been one of the most
challenging and interesting presentations, but I think
it's time to go eat lunch.
We can return to this maybe in the
discussion. They are very provocative concepts and
some very attractive thoughts.
DR. GOLAY: Our team remains eager to
CHAIRMAN KRESS: Remember at two o'clock
up stairs in the White Flint II Conference Room rather
(Whereupon, at 12:59 p.m., the meeting was
recessed for lunch, to reconvene at 2:00 p.m., in the
White Flint II Conference Room.)
CHAIRMAN KRESS: Okay. It's time that we
went back into the section again.
And the standard request is that you'll
have to identify yourself and tell us why you're
qualified to talk to this --
DR. FORSBERG: August body, right?
CHAIRMAN KRESS: Right. So with that I'll
turn it over to Charles and I'm looking forward to
No, no, we're not recusable on this one.
So you might want to introduce yourself,
DR. FORSBERG: I am Charles Forsberg from
Oak Ridge National Laboratory. I guess I've been
involved in every type of fuel cycle you can imagine,
plus some reactor designs, and I'd like to discuss
some alternative reactors and fuel issues and future
nuclear power issues.
I think the workshop here is quite
appropriate because we're looking at the long term
issues of nuclear power, nuclear power options for 20
to 30 years.
But if you look out 20 or 30 years you
have to ask some more fundamental questions. The
first fundamental question is: what are you going to
use the energy produced from a nuclear power reactor
There's an implicit assumption most of the
time, and that is that electricity is the primary
product, the primary final product of a nuclear power
plant. That assumption is, of course, historically
But if you look out to the future 20 or 30
years, there may be other uses of nuclear power that
may also be as significant as the existing nuclear
power industry in the United States.
It's this particular subject I would like
to address. In particular, I'd like to address the
advanced high temperature reactor for hydrogen and
This is a joint effort of Oak Ridge
National Laboratory and Sandia. I should emphasize
here that when we talk about the use of a reactor for
multiple purposes, for example, hydrogen and
electricity, it changes the technology and it may
change the regulatory structure.
The production of hydrogen requires -- has
some very special technical requirements, and those
technical requirements may also impose some very
unusual regulatory issues.
So I'd like to address both issues, the
issues of hydrogen production and use the requirements
needed for hydrogen production to define a reactor
concept, which leads to some of the regulatory issues.
Could I have the next slide?
I'd like to discuss four subjects -- three
subjects: is a nuclear based hydrogen economy in our
Second, an advanced high temperature
gas -- high temperature reactor for hydrogen
production or electrical production.
And third, regulatory implications.
May I have the next slide?
I start with a question: is a hydrogen
economy in our future?
And I put in parenthesis something I think
that many people may not recognize, and that is it may
already be here. In fact, I'm going to talk about
hydrogen economy with -- hydrogen economy without
talking about hydrogen fueled vehicles. I'm not going
to talk about distributed hydrogen. I'm going to
spend one slide on that.
Rather, I'm going to talk about old
fashioned hydrogen consumption, the old fashioned
economy that uses a great deal of hydrogen.
Could I have the next slide.
We're seeing rapid growth as expected in
industrial demand. Currently the production uses --
growth of hydrogen production uses about five percent
of the natural gas in the United States, plus a large
quantity of refinery byproducts. It's a big energy
If the projected rapid growth of hydrogen
consumption continues, the energy value of the fuel
used to produce hydrogen will exceed the energy output
of all nuclear plants by about 2010, and continue to
expand at a very rapid rate like ten percent per year
There are two users, one which I suspect
will be rather static over the next couple of decades.
That's the chemical industry, to bake ammonia and
methanol. It's a large consumer today, but it's
probably not a rapid growth market.
The rapid growth market and the driver for
hydrogen consumption in the U.S. is the changing
refinery conditions that are driving up the hydrogen
demand. I'm going to go into this in more detail, but
there are basically three things that are happening.
The oil supply is changing. We're
beginning to use more heavy crude oils, fewer light
Second, there's a demand for cleaner fuel.
And third, there's a changing product
Thirty years ago, the primary use of crude
oil was to refine it into home heating oil. These
days, of course, it's gasoline.
Last, if non-fossil sources of hydrogen
are used, lower value refinery streams can be used to
make gasoline rather than hydrogen, and thus reduce
Could I have the next slide?
I want you to spend some time on this
slide to explain what's happening in the refinery
industry and why increasing use of more abundant crude
oils reduces refinery yields, unless non-fossil
hydrogen is used.
This is where we were, let's say, 30 years
ago. We primarily used light crude -- light, sweet
crude oils. These crude oils you could put into an
old Chevy engine, turn on the ignition, and it would
start. It would work. Didn't even need a refinery.
Had a little bit of refining, produced the nice, dirty
fuel, but it worked.
Things are changing in two ways, in two
dimensions. The first, we're going from light, sweet
crude oil to heavy, sour crude oil, like Venezuelan
crude. Venezuelan crude's about six percent sulfur.
If I put Venezuelan crude in one of these cups, I
could turn it over after -- if it was at room
temperature, and come back in a half hour, probably
before it would stain this table. It's thicker than
Needless to say, this does not work well
in a car, and thus, it takes a tremendous amount of
refining to make a clean fuel.
So we're in a transition from the upper
left to the lower right. That's what's driving the
hydrogen demand in the U.S.
The very light crudes have a hydrogen to
carbon ratio of about two to one, which is about what
gasoline is, two hydrogens per one. The heavy sour
crudes from Venezuela have a hydrogen to carbon ratio
as low as 0.8 to one. To make gasoline you've got to
get over to two to one.
So there's a tremendous hydrogen input if
you take a sour crude and go this direction.
At the same time people have decided to
take sulfur out of crude oil. They don't like sulfur
in their tailpipe. They've also decided they prefer
to have a gasoline supply that is relatively nontoxic,
that is, we're removing things like benzene from the
gasoline supplies of the United States. And the
consequence of that is more and more hydrogen
DR. POWERS: It even goes beyond that
because by taking out the aeromatics you reduce the
octane level -- octane rating of it, and so now you
have to do more processing on the octanes.
DR. FORSBERG: Yes.
This type of refinery has about 95 percent
efficiency. That is for every 100 BTUs going in here
you get 95. This type of refinery for every 100 BTUs
you get about 80 BTUs out. So the refinery efficiency
Now, what's happened is that 30 years ago,
40 years ago refineries actually made excess hydrogen.
It was flared, surplus product. Thirty years ago,
they were hydrogen neutral. These days they're
hydrogen hogs, and they make their hydrogen by taking
some bottoms of the crude and putting it into a
hydrogen plant to make more hydrogen, and they also
consume very large quantities of natural gas that goes
into making gasoline.
The bad news, of course, as you've
probably heard, is natural gas prices are up. They've
doubled, some cases tripled in the last couple of
years. We now have a situation where natural gas --
where the gasoline prices are coupled to natural gas
prices, as well as oil prices.
This is something we have not previously
seen in our history, different kind of economics,
different kinds of issues.
A five dollar per million BTU natural gas
makes expensive electricity. Five dollar per million
BTU natural gas is going to make very expensive
hydrogen, and thus, there's a potential of a very
large market if you can find economic methods to
produce hydrogen for the refinery industry.
There's also a danger that if you don't
find methods to produce economic hydrogen, what you're
going to do is drive much of this industry offshore to
areas that have low priced natural gas. So what we
have is a changing -- changing environment in terms of
crude oil, a changing environment in terms of the
product, and that in short is what's driving the
hydrogen demand and causing the very rapid increase.
The question is can we find another source
of hydrogen, that is, a non-fossil fuel source of
And today I'd like to discuss the
possibility of using nuclear power or nuclear energy
as that source of hydrogen.
Could I have the next slide?
There are potential multiple economic
benefits for non-fossil sources of hydrogen. There
are four of them, and they're independent of how you
make the hydrogen: increased transportation fuel
yield per barrel of oil. The lower value oil
components are converted to transport fuel rather than
That would save you perhaps ten, 15
percent on oil imports, and of course, that would
reduce oil imports and also reduce natural gas.
Second, if you have cheaper hydrogen, one
can make greater use of heavy crude oils. They're far
more abundant than light crude oils, and more
importantly, most of the heavy crudes are in the
Western hemisphere, happen to be what we have, what
the Venezuelans have, and what the Canadians have.
In the United States it turns out our
worst crudes are in California, by convenience.
DR. FORSBERG: Third, competitive chemical
industry. There's a real concern in the chemical
industry that if those high natural gas prices
continue, we're going to drive much of the chemical
And last, of course, you have much lower
carbon dioxide emissions.
In short, what's happened is the chemical
industry is having a changing world.
Now, I thought I should put in one slide
about the hydrogen economy because if you pick up all
of the popular newspapers and magazines, what they
always talk about is the hydrogen economy, and what
they mean by the word "hydrogen economy" usually is as
liquid hydrogen or pressurized hydrogen is a transport
fuel, and distributive power.
I won't make any claims whether or not
they hydrogen economy will fly. Don't know. What I
do know is if you're ever going to get here, you
better have a very large infrastructure today to get
to a hydrogen economy because otherwise you'll never
get the economics of scale, and making this transition
would be extremely difficult.
So the development of non-fossil hydrogen
is important, both for the refinery and chemical
demand, but it's also very important if you want the
option of a hydrogen economy, because a cold start of
a hydrogen economy would be an extraordinarily
difficult thing to do if you had to bring up large
hydrogen production facilities with economics of scale
at the same time while you're developing the uses for
I'll start at the nuclear side of the
issues here. Hydrogen can be made from -- hydrogen
can be produced with heat from a nuclear reactor.
Basically heat and water equals hydrogen and oxygen.
Nuclear energy would compete with natural gas for
Natural gas is a primary way we make
hydrogen. We do have very high natural gas prices
right now, about five dollars. There are a couple of
things that are, of course, very nice about nuclear.
In terms of refinery demand, the hydrogen demand is
almost constant, which means you have a constant
hydrogen demand, which would, of course, better match
a nuclear low.
Well, that's the good news. The bad news
is it's not easy to make hydrogen from water. There
are processes with projected efficiencies greater than
50 percent. However, big point to be made here: high
temperature heat is required, 800 to 1,000 degrees C.
If you're going to make hydrogen from nuclear power,
it's going to take a very special machine to do so.
Existing commercial reactors cannot
produce heat at these high temperatures. You have to
have an alternative reactor concept or concepts.
I'm going to -- the next slide I will show
you one example of a hydrogen cycle. This is a
chemical process to convert high temperature heat and
water to hydrogen and oxygen.
About 1,400 cycles have been invented.
People have examined them. The competing -- most of
the competing cycles are called sulfur cycles. This
one currently is the leading contender, the one that's
receiving most of the research in Japan, which has a
moderate sized program in this area.
It's called the iodine-sulfur process. we
start with heat at 800 to 1,000 C. We produce oxygen
and hydrogen with, of course, the input of water. The
key chemical step that couples with the nuclear
reactor is the decomposition of sulfuric acid into
water, sulfur dioxide and oxygen at 800 to 1,000 C.
The oxygen, of course, is a byproduct, or
a waste product. The sulfur dioxide is circular --
cycled around, mixed with water and iodine to form
hydrogen iodine and sulfuric acid. The sulfuric acid
goes back through this cycle. They hydrogen iodine
goes through a second cycle that ultimately yields
hydrogen gas and iodine. So you have two sets of
chemical reactions in the reactor.
The key thing about all of these cycles
that the people have looked at that look reasonably
practical is there's this 800 to 1,000 degrees Celsius
temperature, and they're coupled to some complex
chemistry and some fairly aggressive chemistry, such
as the decomposition of sulfuric acid.
I mentioned that because what it means is
this is your interface, and you have this chemical
plant on this side and your nuclear plant on this
side. This chemical plant for, let's say, a 600
megawatt reactor would be producing about 100 million
cubic feet of hydrogen a day.
You know, there are going to be a few
1,000 or tens of thousands of tons of reagents in
these systems. And if you think of a couple of
thousand tons of sulfuric dioxide or a couple of
thousand tons of iodine, you recognize there's some
non-trivial hazard issues associated with the right
side of the plant.
In fact, you might have a debate on
whether or not your primary safety concern is the left
side or the right side. It's not intrinsically
obvious to me that you can make a blanket statement
that safety problems are on the nuclear side if you're
into this kind of game.
I would now like to describe one reactor
concept that we have been examining that might meet
these requirements, and they're very special
requirements. That's an advanced high temperature
reactor, a reactor concept for hydrogen production.
The main point, however, I want to
emphasize with this example is not only describing the
example, but emphasize that different products may
require different reactors.
If somebody proposes a new product from a
nuclear reactor, it may very likely imply you have to
think about how you're going to design the reactor,
and it may be fundamentally different than anything
you've built before.
We've been thinking electricity,
electricity, electricity. That imposes one set of
requirements on the reactor, one set of requirements
on the regulator, one set of requirements on the
If you change the product, you may need to
change the reactor, the regulatory structure, and how
the operator thinks about things. That's a very
important message I'd like to leave with you today,
that there really are some large changes if you think
about changing products.
We've only begun to examine this issue.
I'm sure it's not an issue that's received much
examination anywhere else, but it's important to
recognize, you can't apply old rules if you change the
product. Some things are easier; some things are more
Could I have the next picture or the next
There's a very simple description cartoon
of this concept. What we're proposing in this case is
a graphite reactor, similar to a MHTGR with graphite
fuel. The molten salt goes up in the molten salt
coolant. We're using as an example a lithium
fluoride, beryllium fluoride salt, although there are
several other salts that are potential candidates.
The heat is transferred in the heat
exchanger to the chemical plant and the molten salt
goes back to the reactor, but the basic reactor core
would be similar to an MHTGR modular high temperature
gas filled reactor, except that the coolant is a
Heat would be transferred in a special
heat transfer device to the chemical plant. It takes
water in, produces hydrogen and oxygen.
Important point to be noted about this
interface. High temperature, but it's also a chemical
plant. Inside this side of the heat exchanger we're
talking about the catalytic decomposition of sulfuric
So this has a solid catalyst bed in tubes,
has a variety of other design features that can impact
the design of the nuclear side of the plant. This is
not a water interface or a helium interface or a gas
turbine interface. It's a chemical plant interface,
with all the constraints and issues that you have to
address in operating a chemical reactor.
And that of course includes the regulatory
issues of that interface. There are some very serious
regulatory issues that you don't normally think about.
Could I have the next slide?
Let's think about what we might want if
we're going to make a high temperature reactor.
What's -- what are our requirements? What would we
prefer to have, especially if we're going to have one
that is blazingly hot?
Well, the first requirement is we really
want low pressure operation. We want low pressure
operation for a couple of reasons. First, medals
become weaker at higher temperatures. If we're going
to higher temperatures we'd rather avoid the situation
of high temperatures and high pressures. That's a
And at 1000 C., strength of materials
becomes and endurance of materials becomes a major
issue. So we need the low pressures to minimize
We also would like to match the chemical
plant pressures. The chemical plant pressures in this
system will be near atmospheric.
We would rather not have a high pressure
primary system feeding to a low pressure chemical
plant because in that case we have to worry about what
happens if you have a leak in the high pressure
nuclear system and it pressurizes a low pressure
chemical plant with a high inventory of hazardous
So we have to worry about the nuclear
plant doing bad things to the chemical plant, and as
I say, that's not a trivial detail if you have
thousands of tons of nasty materials. So this is a
situation where the nuclear plant could be a threat to
the chemical plant or vice versa, and you have to
think about both and design to avoid those issues.
It's a different mindset. We think about
a particular nuclear plant. In this case we've got to
protect both plants.
Second, we want very efficient heat
transfer. We need to minimize the temperature drops
between the nuclear fuel and the application to
deliver the highest possible temperatures, and for
that reason we have chosen a liquid coolant.
Can I have the next slide?
I'm showing here a picture of the Japanese
high temperature engineering test reactor fuel that's
designed for 950 C. helium exit temperature. This
reactor is currently operating. It's in its first
year of operation. They are not yet to 950 C. If I
remember right, they are somewhere around 850 C., and
after a couple of years they're going to run the
temperature up to 950 C.
And it's a coated particle fuel like the
fuel we would use. It's slightly different type of
fuel element because they run into much higher
Now, the reason I point this out is
they're running at 950 C. We'd like to run 1000 C,
maybe a little warmer than that, but this is 950 C in
helium. And if you use a much better heat transfer
material, like a molten salt, you reduce the
temperature -- the temperature drops the required to
transfer heat inside the fuel element, and thus a 950
C. exit temperature for helium is probably
substantially over 1000 degrees C. for molten salt
because it's a better coolant.
So you can have higher temperatures with
the same fundamental fuel limits which are associated
with that coated particle fuel. So if we can improve
the heat transfer we can knock down the temperature
drops elsewhere in the system to reduce the stress or
reduce the difficulty of making a fuel element.
If you're pushing to high temperatures,
the goal is to minimize the stretch that's required.
Could I have the next slide?
The other important item is the coolants.
Why do we want molten salt coolants?
Well, they allow low pressure operation at
high temperatures compared to traditional reactor
coolants. The particular salt we've mentioned here
we'd operate around 1000 C. It has a boiling point of
about 1,400 C, which gives us 400 degrees C. between
the operating point and the boiling point. And of
course, that means we're a very low pressure system.
To give you a comparison, sodium
unfortunately boils at a low boiling point of 883
degrees C. Hot machine if you're going to make
hydrogen. It's unavoidable. And of course water and
helium are further on down the loop.
Can I have the next slide?
Needless to say as a new concept we've
only begun to examine the safety issues of this kind
of reactor. There are many, many uncertainties, but
we'll identify those that look potentially attractive,
but please recognize we're a very, very early in the
Of course, one of the key requirements for
both the chem. plant and for nuclear safety we believe
is low pressure coolants, subatmospheric coolant.
Escaping pressurized fluids provide a mechanism for
radioactivity escaped from a reactor during an
A low pressure salt coolant minimizes
accident potential for a radioactive transport to the
It also minimizes chemical plant
pressurization issues. So for this kind of
application one would like to have very low pressure.
Second, molten salt has a good coolant
characteristic to provide high safety margins for many
We believe with a molten salt that we
could have significant natural circulation, which
would help in certain kinds of abnormal conditions.
It has a high heat capacity.
And last, although we don't fully
understand the chemistry of it and are only beginning
to think about it, molten salts have the unusual
features that most fission products dissolve in molten
salts, such as cesium and iodine. And hence, the salt
itself becomes a --
DR. POWERS: And those particular salts
that you've got there, just about everything
dissolves, even the things we think are nominally
DR. FORSBERG: I know. This is an unusual
coolant. But it's a different approach to safety
also, and that's why I mention it because we normally
don't think of coolants as fission product absorbers.
And in this case the coolant is a fission product
DR. POWERS: Yeah. I mean, we saw this in
TMI, that you blow efficient products through water.
They stay in the water.
DR. FORSBERG: Yes.
DR. POWERS: Okay. And here all you're
doing is magnifying that with a coolant that has a
higher dynamic range than water does.
DR. FORSBERG: Yeah. I think it's an
important issue though because there are different
approaches to safety also that you can think about
when you go to these high temperatures and when you go
to other coolants.
We're using molten salt, but there may be
other cases where you can think about fundamentally
different approaches to safety than the traditional
approaches that we have historically used. When you
go to different systems you need to think beyond the
box, outside the box.
As I say, we're not far enough into this
to give you any answers, but there some interesting
potentials. In this particular concept the passive
decay-heat removal system is similar of that of other
proposed reactors. That is, heat conducts outward
from the fuel to the pressure vessel, to the passive
decay-heat cooling system, and our conceptual design
limits the power to about 600 megawatts, the same as
the HTGR, because the worst design condition for this
reactor is you lose the coolant, and then you have
essentially an HTGR, a depressurized HTGR. So it has
essentially the same temperature units.
I would emphasize very early in our
conceptual thinking about this, but what comes out of
this kind of thinking is it's a very different kind of
system. It has potentially some different approaches
to safety that we have not historically used, some
DR. POWERS: I think it has some
interesting safety issues that are peculiar to itself.
DR. FORSBERG: Oh, yes.
DR. POWERS: I mean, this is the classic
problem of over-cooling accidents. Start-up is kind
of an interesting --
DR. FORSBERG: Yes.
DR. POWERS: -- challenge in this reactor.
Start-up and shutdown, both are interesting events in
DR. FORSBERG: What he means by start-up
is that this material thaws, becomes a liquid at about
400 C., molten salt. So you have a system that is, on
start-up when it turns to liquid, is already
moderately warm. In fact, it's hotter than any light
water reactor on start-up, which is not your normal
way of thinking about things.
DR. POWERS: There are salts that one can
imagine that have much wider --
DR. FORSBERG: Yes.
DR. POWERS: -- liquidous boiling ranges
than this fluoride system. Have you looked at any of
DR. FORSBERG: Not in any detail. So far
we've only begun to look at the fluoride systems, and
we're looking at this salt and a salt that has
zirconium potassium sodium fluoride.
DR. POWERS: Yeah.
DR. FORSBERG: Which of course gets rid of
the beryllium issue. So that's why that one's being
looked at. There are a variety of other options.
DR. POWERS: Going down -- going to the
more complicated ternary systems does get you a
DR. FORSBERG: Yes.
DR. POWERS: -- liquidous range. That
particular salt's not a good one for a broad liquidous
DR. FORSBERG: Yes.
DR. POWERS: But you can get fairly broad
liquidous ranges so that at least you're start-up
might be -- I mean, you've got to worry about how to
preheat this stuff.
DR. FORSBERG: Yes. Yes.
DR. POWERS: And if you wanted to use a
water-base preheater technology, which I think you
would, you want something that melts within the range
you can get with water.
DR. FORSBERG: Unusual set of issues. I
should mention here, which I didn't mention earlier,
one of the desirable features of fluoride salts is
they're fully compatible with graphite. Most of you
probably are used to aluminum tin cans. Well,
aluminum is made by the hull process where you
dissolve the aluminum oxides in a fluoride salt that's
in a graphite bath.
And the aluminum industry has been using
fluoride salts and graphite for a little over a
century now. And they're thrown everything, including
the kitchen sink, in their graphite baths over a
century of experience.
So there's at least a century of
experience of running a very wide set of fluoride
salts and graphite baths with an extraordinarily wide
level of impurities, not intentionally, but
accidentally over 100 years of operational experience.
MR. SIEBER: I presume you pumped this
molten salt around the surface.
DR. FORSBERG: Yes.
MR. SIEBER: Are there pumps that can
actually do that at these temperatures?
DR. FORSBERG: Yes. Well, we haven't done
anything at this temperature. The molten salt reactor
experiment at Oak Ridge operated at 700 C. Now, the
difference is in that reactor the uranium was
dissolved in the salt. There was not a solid fuel
element. But that operated about a much lower
temperature of 700 C., and of course, nobody has
operated a salt system at these temperatures.
MR. SIEBER: You start this reactor with
no flow at all.
DR. FORSBERG: That's right.
DR. GARRICK: Are you going to say
anything about performance characteristics other than
temperature and pressure?
DR. FORSBERG: We're very early in the
game, and I wouldn't make any promises that we have
any information that would be considered credible.
It's very, very early in the game.
DR. GARRICK: Just cycle times?
DR. FORSBERG: That's right. We started
this effort about six or eight months ago, so we're
very early in the game. Starting with the observation
that there some -- maybe some demands for a very high
temperature reactors, and if you have very high
temperatures, how do you get there with the materials
that may exist, and obviously you throw out water; you
throw out sodium.
DR. GARRICK: Right.
DR. FORSBERG: And by elimination you're
sort of left with graphites and molten salts if you
want to really run the temperature up.
The same problem -- it's somewhat similar
to the issue of the aircraft nuclear propulsion
program in the '50s. They investigated many coolants
for an aircraft nuclear propulsion system that had a
solid fuel and a heat transfer loop, and the original
nuclear work on molten salt transfer was done as part
of the aircraft nuclear propulsion system because at
high temperatures with low pressures molten salts were
the only game in town. There just weren't any other
MR. SIEBER: And it operates under a solid
coolant condition, no pressurizer or anything. You
just pump in --
DR. FORSBERG: That's right.
MR. SIEBER: -- to maintain the pressure.
How does it accommodate power swings?
You know, it expands and contracts.
DR. FORSBERG: Yes, it's regular expansion
and contraction of the coolant, plus the doppler
coefficient of the --
MR. SIEBER: But that could be pretty
sever in some accident situations.
DR. FORSBERG: Yes. We're not at the
point where we've investigated the details of how
you're going to handle these types of events.
MR. SIEBER: All right. Thank you.
DR. FORSBERG: We're at the issue of
materials and what materials can you actually build
the thing out of that you have a reasonable chance of
operating at these temperatures. A 1,000 C. is a very
severe operating environment.
MR. SIEBER: It's hotter than a super
critical coal boiler.
DR. FORSBERG: That's right.
MR. SIEBER: You get up to those
temperatures and the tubes just melt.
DR. FORSBERG: That's right.
DR. POWERS: Have you thought about what
your primary pressure boundary is going to be?
DR. FORSBERG: There are three obvious
choices. One is a molybdenum alloy. Then there is
some oxide dispersion stainless steels that may have
the capability, and then there are also graphites.
But we're very, very early. And all of those things
are cases where people have shown in the laboratory
that the materials are capable of doing something, but
nobody knows whether or not they could be made on a
large scale or whether you could fabricate them or
whether you could convert this into a practical
So what we have is materials that are used
-- we have -- there are a number of high temperature
materials that are used in research applications that
operate at these conditions normally, in a research
environment, but have not been used in a production
environment. So what you have is materials that, yes,
some of them have been used for 40 years, but only in
a research environment. There's a big difference
between research and production.
DR. POWERS: There's a big difference
between research environments and flowing, high
velocity flows and things like that.
DR. FORSBERG: Yes.
DR. POWERS: In particular, on any kind
alloy. The problem here is kind of interesting. It's
not carbon extraction, it's alloying-agent extraction.
DR. FORSBERG: That's right. That's
exactly right. There is a fair amount of experience
based up to about seven, 800 C. Above 800 C., the
databases begin to get very sparse.
Could I have the next slide?
If one can produce a high temperature
reactor, obviously the options for the production of
electricity, that one can use a high efficiency helium
gas turbine cycles, conversion efficiency greater than
50 percent, provide isolation of the power plant from
a reactor using low temperature drop heat exchangers,
and advanced gas turbine technology.
In the longer term there's the option of
direct thermal through electric production. That is,
no moving parts, methods to produce electricity from
high temperature heat. It would radically simplify
the power plant design. It has the potential for
major cost reductions.
However, it must be emphasized this is a
longer term option. Current solid state technology
results in thermal electric conversion efficiencies
between 20 and 25 percent, and the technology is
clearly not ready to be considered as an industrial
technology with those low efficiencies.
If they continue to make progress, one
could hope for the possibility in ten to 15 years of
a radically simplified power plant.
May I have the next slide?
This shows an advanced Brayton cycle. You
have the reactor. You have the turbine cycle, and of
course, you have an intermediate heat exchanger loop.
In this particular case, the intermediate loop is to
separate the high pressure helium system from the low
pressure reactor and protect the reactor from
Could I have the next slide?
This shows that the possible use of direct
conversion systems, where you'd have a molten salt go
through a heat exchanger and produce electricity
directly. That is, you have electricity, the molten
salt going through a tube. You'd have a solid state
converter on the outside of the tube, water cooling on
the outside of the solid state converter, with direct
production of electric current.
As I mentioned, this potentially is very
attractive in the long term, but the technology does
not currently exist to get the efficiency high enough
to be of commercial interest. It's only 20 to 25
But if they make sufficient progress, it
has major implications in terms of a radical
simplification of nuclear power plants.
Of course that technology would probably
also apply to sodium cooled reactors and a variety of
other high temperature reactors. And it's a long term
option, not a short term option, but something to keep
in mind because in 20 years we may have the conversion
devices capable of doing it, which would be a true
These molten salt coolants have extremely
low activity levels compared to sodium or water.
DR. POWERS: You were talking about sodium
just now, so --
DR. FORSBERG: Sodium you would have
activity. But molten salts themselves are extremely
low activity, far, far less that water or sodium.
That's one of the really nice things. That's one of
the nice things about molten salts.
MR. SIEBER: The physical size of the
converters must be huge to get the commercial levels
of power out of them.
DR. FORSBERG: You have to predict what
it's going to be in 20 years, and they've been
shrinking dramatically and the efficiency has been
going up dramatically, but the question is will that
continue for another 20 years. And I don't know.
DR. POWERS: And they produce a direct
current; don't they?
DR. FORSBERG: Yes, they produce a direct
DR. POWERS: So we get long term direct
current transfer with no loss.
DR. FORSBERG: Well, I'm not sure about
the no loss part.
DR. POWERS: No, well, you don't have the
radiation loss. That's what -- I mean that's the
biggest loss you have in --
DR. FORSBERG: Yep.
DR. POWERS: -- transmission. We go back
and Thomas Alva Edison may have been right after all,
DR. FORSBERG: That's entirely possible.
Could I have the next slide?
Obviously high temperature creates
development challenges. That's the understatement of
the year probably. The AHTGR uses some demonstrated
technologies. The fuel technology is demonstrated.
The coolant technology is demonstrated. Both require
more development work. But the base technologies are
Of course at AHTGR it requires advanced
technology. The most important one is the high
temperature materials of construction where there are
plenty of laboratory materials capable of doing it, as
measured in the laboratory, but have not had the kinds
of tests required for long term operation.
And they are not industrial materials at
the current time. Lots of issues in terms of system
optimization, heat exchangers and particularly the
heat exchanger that couples with the chemical plant,
and of course lots of work on hydrogen and energy
Could I have the next viewgraph?
Radio chart implications of hydrogen
production. If we talk about an alternative use of
nuclear power, there are some very large regulatory
implications. The first, most important probably in
many respects is that we're talking about different
owners, the oil and the chemical industries. Pluses
The key item, first item to be noted is
they are much larger than traditional utilities.
ExxonMobil last quarter earned $5 billion. They're
approaching 300 billion in sales. Shell is a little
bit behind, but not far. Very, very large
organizations, which means buying a reactor is not a
serious capital outlay.
It's a strange way to put it, but in that
large of an organization it's not a major -- you know,
a CAT cracker in a large refinery costs four billion.
Hibernia offshore platform costs seven billion. These
are the kinds of things your boards of directors see
normally. Oh, it's only like four billion, seven
billion, three billion --
MR. SIEBER: Pretty soon you're talking
DR. FORSBERG: You're talking serious
money. But it's a different mindset. They're very
concerned about, obviously, the cost per unit product
delivered, like the cost per million cubic feet of
hydrogen. But the capital cost issue would not be a
major issue for a chemical company or an oil company,
because it's just not that kind of dollars.
The other thing that's important though is
they have very different perspectives about risk and
how they do business, and I'm not sure how that would
interact with the Nuclear Regulatory Commission, but
it's a different philosophy and different ways of
thinking about it.
They are, of course, used to handling
large quantities of very nasty materials. So in that
sense there's a commonality, but there's a different
culture. It's a very different culture, and I have no
good feel of what that kind of interaction applies,
except there would be a lot of grinding of teeth.
DR. POWERS: Yeah. I mean, they deal with
a different set of regulatory --
DR. FORSBERG: That's right.
DR. POWERS: -- body, but time scales tend
to be a little more shorter term.
DR. FORSBERG: Yes. The second item I'd
like to emphasize is both chemical and nuclear safety
must be considered, and in my mind it's not clear
where the primary hazard is.
The chemical plant must not impact the
nuclear plant. Equally important, the nuclear plant
must not impact the chemical plant. When you think
about boundaries between facilities, you must think
about both directions.
And that's something we don't normally do
in a nuclear facility. A nuclear facility, well, we
can trash a turbine and we don't worry about it. We
can trash a steam generator; we worry about the
economic costs. But we don't worry about the nuclear
plant in terms of safety, damaging secondary
In a chemical plant interface one has to
be -- this gets to be a major regulatory issue.
Last, if we're talking about alternative
uses of nuclear power we're going to have to do some
serious thinking about non-traditional reactors that
don't have water, do not have liquid metal and do not
And that just flows from the different
requirements, different applications. We just have to
rethink what you want based on requirements.
Can I have the last slide?
Some conclusions. Economic methods to
produce hydrogen from nuclear power may provide
multiple benefits. Increased gasoline and diesel fuel
yields per barrel of crude oil will reduce dependence
on foreign oil. It's a long term pathway to the
Higher temperature heat allows new, more
efficient methods to produce electricity.
Last, reactors with different
characteristics may be preferred for such very
different uses. In particular, if you're dealing with
very high temperatures and you need low pressures, it
may require a fundamental rethinking of how you
approach reactor design, and also the regulatory
issues associated with those plants because they will
be very, very different than the traditional utility
That completes it.
CHAIRMAN KRESS: Charles, back in the
distant past when I worked on molten salt reactors, we
have a saying about talking about hazards. We said --
the saying was "No wing, no sting."
DR. FORSBERG: Yes.
CHAIRMAN KRESS: There wasn't any way to
get the fission products out to the atmosphere or
there didn't seem to be. The reason I say that is why
wouldn't this be an attractive concept for just
electricity generation? Because you don't have these
extra hazards then of the chemical plant and so forth.
And just by itself it looks like would be a pretty dog
gone safe, inherently safe concept.
DR. FORSBERG: I think it has many
potential attractivenesses. And that's worth
considering, but I think an important other
consideration is that in this particular case you may
also have multiple markets. And it's those multiple
markets that may make it much more attractive for a
serious consideration as an advanced reactor concept.
But clearly if you develop this, one will
take a very hard look at it as a electric power
producing reactor because those safety benefits apply
to any other application as long as it doesn't have
So, yes, you're right. There are
tremendous advantages if you can make it work and then
particularly both in the electrical context and in the
CHAIRMAN KRESS: And the electrical
context you could back off a little on the
DR. FORSBERG: Oh, yes. Electrical
context you can drop probably 200 C. in the
temperature and not be too concerned about it.
CHAIRMAN KRESS: You'd still have some
sort of interface with --
DR. FORSBERG: That's right.
CHAIRMAN KRESS: -- gas, helium or --
DR. FORSBERG: Yes.
CHAIRMAN KRESS: -- water, one or the
DR. FORSBERG: Yes.
CHAIRMAN KRESS: I would think helium with
the direct cycle, but --
PARTICIPANT: Tom, there's somebody behind
CHAIRMAN KRESS: Okay.
MR. CARLSON: Don Carlson, NRC staff.
I have a couple of questions about your
use of a lithium based salt as your coolant.
DR. FORSBERG: Yes.
MR. CARLSON: Lithium 6 is a strong
neutron absorber and produces copious amounts of
DR. FORSBERG: It's isotopically separated
MR. CARLSON: Lithium 7?
DR. FORSBERG: Lithium 7. If we -- we're
looking at several coolants, some with lithium and
some without lithium. The ones that include lithium
have Lithium 7 because otherwise the neutronics
MR. CARLSON: Well, even impurity levels
of Lithium 6 would give you lots of tritium.
DR. FORSBERG: Yes.
MR. CARLSON: In fact, in the pebble bed
reactor work in Germany, where they were considering
processed heat applications, the very small amounts of
tritium on the order of 1,000 Curies per year were a
concern in terms of getting the tritium into the
DR. FORSBERG: Yes. That's why we're --
one of the reasons why we consider multiple coolants.
Each coolant has particular advantages and
disadvantages. Neutronically the lithium beryllium
fluoride is a tremendous advantage. But the
disadvantages include tritium and a couple of other
The sodium potassium, sodium potassium
zirconium fluoride avoids that problem. It has a
little more activity in the coolant, has some other
issues. So one of the issues in a molten salt reactor
is which coolant you want. They all have the same
general characteristics, but that's where the tradeoff
comes on, coolant A versus coolant B.
You're absolutely right. That's why the
coolant decision has not been made and why several
coolants are being considered. All fluoride salts,
but they have different benefits.
CHAIRMAN KRESS: Other questions,
It's hard for me to see behind me. I have
been accused of having eyes in the back of my head.
DR. POWERS: I guess I can't say too --
emphasize too much what Charles' point is, that when
we think about new applications, we need to be -- we
need to think creatively and innovatively on these
Have you looked at some of the silicon
nitride, silicon carbide type refractories for your --
as a material?
DR. FORSBERG: We haven't done any serious
DR. POWERS: I'm really ignorant in that
area, but I know that they have done a lot of things
in connection with molten salts --
DR. FORSBERG: Yes.
DR. POWERS: -- with those kinds of
materials. And the nice thing about them is at these
temperatures they're ductile.
DR. FORSBERG: Yes, I know.
DR. POWERS: They're no longer behaving
DR. FORSBERG: Dana points out the very
funny thing. With materials you have to start
rethinking. These temperatures, all sorts of
materials that you normally think as brittle become
wonderfully ductile. So there's a plus and there's a
minus. You have to worry about their tensile
strength, but the ductility -- well, gee, like
graphite itself. You know, graphite gets stronger and
more ductile. It begins to look like a construction
material at these temperatures.
DR. WALLIS: Silicon carbide becomes a
very good conductor of heat too.
DR. FORSBERG: Yes, yes. One has to be
very careful about taking preconceived notions when
you move into these systems because if you do you will
be surprised. They don't apply.
DR. GARRICK: Have any early looks at this
indicated real problems with respect to the
interaction of the chemical part of the plant and the
nuclear part of the plant?
And if so, does that suggest other
concepts that might be attractive with increasing
efficiencies and furnaces and electrical systems of
going maybe electrical first and then to hydrogen
DR. FORSBERG: People have looked at
making hydrogen from electrolysis. The problem with
hydrogen from electrolysis is that if you include the
nuclear plant efficiency and the electrolysis
efficiency, you're down to a range of about 25 to 30
percent total efficiency, whereas the direct cycles
have about 50 to 60 percent efficiency.
And the general feeling among most people
who have looked at this issue is that that factor of
two in efficiency drop makes electrolysis very
difficult to ever become competitive in production of
DR. GARRICK: That's unless that
DR. FORSBERG: That's right.
DR. GARRICK: -- improves. And there's
real safety problems between the --
DR. FORSBERG: That's right.
DR. GARRICK: -- direct cycle.
DR. FORSBERG: That's right.
DR. GARRICK: Yeah.
DR. FORSBERG: These direct systems have
not really been explored in any detail. Now, we have
looked at some very unique type of heat exchangers
between the chemical plant and the nuclear plant. In
particular, we've been doing some examination of using
radiation heat transfer from the primary system salt
coolant to cold pipes that contain the actual chemical
reagents. Instead of a mechanical heat transfer,
literally have the salt tubes radiate heat in infrared
to absorber tubes that contain the chemical reactors
so that you essentially have no physical contact
between the reactor pipes and the chemical plant
pipes, and that begins to look potentially applicable
above about 900 degrees C.
Below 900 degrees C. the heat transfer
rates are not very attractive. But the heat transfer
rate goes up as T to the 4th, and somewhere around 900
C. you get heat transfer rates that begin to look
attractive for radiation heat transfer rather than
conduction heat transfer.
CHAIRMAN KRESS: Have you looked at that
marvelous material, graphite foam, that's being worked
on at Oak Ridge?
DR. FORSBERG: We've thought about it.
CHAIRMAN KRESS: It seems to have an
extremely high thermal conductivity.
DR. FORSBERG: Yes. We've thought about
it. It's a possibility. We're still very early in
the understanding the requirements for the chemical
plant. Remember the chemical plant, we not only have
to transfer heat, but those tubes in the chemical
plant have catalysts in them and chemical reactions,
and so they have their own set of design constraints
independent of the reactor.
But we have been looking at alternative
ways to couple the plants, and we've looked at the
conventional heat exchangers and also this issue of
radiation heat transfer, which sounds like a very
unusual heat exchanger, but when you run through the
numbers it begins to look like, gee, that's rather
amazing. It may be viable.
CHAIRMAN KRESS: Back to the subject of
this particular Subcommittee meeting. What do you see
as regulatory challenges or implications of -- if such
a plant ever came before NRC?
DR. FORSBERG: Well, the first
institutional one, which would be probably the most
difficult one to deal with, is relationships between
the Environmental Protection Agency, OSHA, and the
NRC, because the chemical plant comes under a
different regulatory structure than the nuclear plant,
and there's been some history to indicate that it is
sometimes difficult to work between different federal
agencies with different philosophies.
So that's clearly the first thing that
The second one, which is related, would be
the need for the technical staffs of EPA and the state
regulator that deals with hazardous materials to work
with the NRC in whatever type of analysis, safety
analysis, would be required to assure that all the
safety issues are properly addressed, both in the
nuclear and chemical side and on the interface.
So I see that the initial problems as both
institutional and technical because we have a separate
structure for regulation of nuclear versus chemical.
Now, that's not true in some other
countries. The Brits have a unified structure, in
which case no problem. But for the United States
where we have, for one reason or another, have got two
different organizations to deal with hazardous
materials, this would be a significant interface
CHAIRMAN KRESS: Are there other
Seeing none, thank you very much, Charles.
And we'll move on to the next item on the
agenda, which is, I think, an NEI presentation, I
DR. WALLIS: Are you the next speaker?
All yours. Do you want this seat?
MR. HEYMER: Can you hear me?
Good afternoon. My name is Adrian Heymer.
I'm a pro jet manager at NEI in the risk informed
We deal with Option 2, Option 3, which is
risk informing the SSCs governed by NRC's special
treatment requirements, risk informing NRC technical
requirements, a few other risk informed activities,
and we've been matrixed across to the new plant group
within NEI dealing with the new plant regulatory
Since we're in the risk informed group,
one of the things that we've come up with is that we
feel that we should start with a fresh sheet of paper
as we deal with the regulatory framework for new
plants, especially since we're not dealing with
necessary light water reactors with different --
dealing with different types of reactors.
And that really comes about because we
don't want to be too burdened with current
interpretations and current philosophies or ingrained
or established thought processes necessarily.
We have run into some cultural issues as
you go through any change process, and these have been
difficult to overcome.
So starting with a clean sheet of paper we
hope that we start off with fresh minds, but build on
our experiences of the past so we don't actually lose
those, but don't become ingrained with them.
Establishing new wired thinking or a new
framework provides some form of measure against which
we can set our requirements, requirements being in the
regulations and the general design criteria and what
we believe are general operating criteria.
And I think it provides a platform for a
better understanding between the people who are trying
to get a license or a certification and the regulators
So not only does it provide a basis for
the regulatory positions, but it helps the industry
establish its own positions as we work through the
development of the framework so that we can come up
with, as we said, a generic framework to cover all
types of plant, and some people think we can achieve
that goal and other people think we can't.
And I think it depends upon the degree of
specificity that you get down into, whether or not you
put the real details in the regulations or do you put
the details in the regulatory guide.
We think there's a need as you go through
looking at where we are today in the current plants.
We've got an oversight process which is risk informed.
And we have regulations which are very much
deterministic. There are some that are moving towards
a risk informed world, but we haven't quite got there,
and in fact we are struggling in some of those areas.
And so it would bring some degree of
consistency between an oversight process and the
regulations, the reg. guides and the way we run and
regulate out plants.
And so what we're looking at is to start
with, and again, it's a starting point for discussion,
is to use the framework that was being developed for
the oversight process, to start not only in the
industry-regulatory interactions, but sort of the
intra-interactions between the industry and we hope
for the discussions within the NRC staff as we move
Why do we want to start there?
Well, quite simply it's out there today.
It is a risk informed type of framework.
Does it cover everything? No. And I'll
get to that in a minute.
But it has, if you like, broken the ice as
regards the changing the cultural mentality that
exists within the industry and the regulatory
establishments, and I think that's only a natural
resistance. There's a natural resistance to change
that you see anywhere that must be overcome.
So we want to be generic to all types of
reactor. We think it's good if you start from the top
and slowly work down and cascade out. And many of our
concepts, I think, are reflected in some of the
presentations I heard this morning. I wouldn't
necessarily say we're going down the same path as
everyone. I heard this morning all those paths, but
certainly there is a common flavor that if you take it
at a high level, that there is a convergence of
thought as we move down towards establishing the basis
for the licensing a new reactor in the United States.
And so we start with the adequate
protection of public health and safety, and there are
some safety goals that are associated with that.
Are they the same safety goals as we have
today? And we believe at the moment they are. It may
be more towards a radionuclide release criteria rather
than a core damage frequency, but it's along those
lines, and those goals have been established.
We do believe you need a new set of
general design criteria, although I do agree with I
think Mike Golay this morning, who said the general
design criteria, if you read them, they are very
And we've got an example towards the back
end of the presentation of where we might go in that.
And I think one of the items that we're going to
struggle with as we move through this is how specific
do we get in the regulations as opposed to trying to
keep it general because the more specific you get, the
more difficult it is to say, "Well, is this going to
be applicable to all regulations, all types of plants,
or not all plants?" And then how do you work that one
There isn't really much or until recently
been much in the regulations regards general operating
criteria or operating regulations. The regulations
were really set in place to deal with design and
construction of plants, and we try to sort of adjust
and bend the regulations into an operating mode.
And I think there needs to be some element
in there. I think when you look at the maintenance
role and you look at 56(a)(4), the maintenance rule,
which is if you lack a configuration control element,
we've begun to put those measures in place.
Whether we need some more or not, I don't
know. But I think we do need to look at the operating
side as well as the design and construction.
It should be a risk informed and
performance based. We've struggled with what does
that mean in the regulatory world. But I think
building on the experiences that we've had with Option
2 and Option 3, with the oversight process, I think we
can come up with a good set of regulations.
And then beneath that, you're going to get
a series or reg. guides or implementation guides that
would be, first of all, regulatory specific.
So how to implement this regulation, and
that's where you may get down into the various
different design characteristics. So you might have
one regulation, but it may have two or three reg.
guides depending upon the type of reactor that you are
talking about. And then you'd have design specific
applications dealing with that, that design element.
So that way the regulations are general.
They're generic. They cover everything. It's a set
standard, but it is fairly high level, and I guess
there is an issue out there as regards finality and
certainty, is the more general you get, the more
reliance you're putting on reg. guides, and is that
regulations and is there a finality in the legal
And we leave the lawyers to deal with
that. That is an issue that has been mentioned on
I just want to touch a few moments now
that I've said what the concept is and we're moving
forward. We are in the process of establishing a task
force made up of industry participants to take a look
at what the framework would be, how detailed it should
be, and give us some input so that we can provide
something as regards an input to the regulatory
process and the development process either at the end
of this year or the early part of next year.
But is that the end of the game?
No, it's not. It's only really the start
because in order to move forward, I think, you really
need some active project. Otherwise, you'll, as you
move into the regulatory discussion, you're dealing
with somewhat of the theoretical hypothetical type of
interactions that have gone on. And I think if you
have a specific program to lean towards, to join with,
that you force yourself to come up with -- you force
yourself to a decision point, and you have to make
And we can always get smarter as day goes
on, but at least you come up with a decision. You
come up to a starting point. So what we see as a
proof of concept type of application, whereby very
similar to what happened in license renewal and Option
2 for South Texas, that we hope is a little bit more
expeditious than Option 2 or the license renewal
approach, whereby you come up with an idea and you
come up with a framework or you come up with a
regulation. And then you move forward with a specific
And the lessons learned from that specific
project and those specific interactions between that
licensee or designer and the NRC get fed back into the
framework, and you adjust as you move forward.
CHAIRMAN KRESS: When you say use license
renewal and Option 2 models, you don't mean the
specifics in there, do you?
MR. HEYMER: No, I mean --
CHAIRMAN KRESS: You mean as a process.
MR. HEYMER: As a process.
CHAIRMAN KRESS: As a process.
DR. APOSTOLAKIS: I think what you
described, Adrian, is really the idea of a pilot. Is
MR. HEYMER: You can call it a pilot.
Pilot's probably too strong a term. We're looking
more or less at proving the concept, proving of the
framework, proving that the regulatory process as the
process is being developed.
And so that's why we think it's important
to have representation into the development of the
industry thought process on the framework from Exelon,
from Westinghouse to cover IRIS, to cover the AP 1000,
to cover the pebble bed from General Atomics, et
So that you get those thought processes in
and there's the concept; that's the framework. Then
you go and perhaps test it with a few applications and
see how it actually works out.
When we've used the term pilot in the past
internally, some people have thought that was perhaps
a too definitive term as you are definitely testing
Here you are testing more the concept, and
then the regulations would be developed from the
pilots or the proof of concept projects moving
forward, and what you've come up with is a draft
And I think if you see or the way we see
it going forward is that there -- we have the
regulatory interaction. We provide input to the
regulatory process. They come forward with an
advanced notice of proposed rulemaking. That goes out
of the street, has public involvement. It comes back;
there'll be more discussions and sessions like this.
In the meantime, the pebble bed and others
are moving forward, and they're talking about
specifics, and that gets fed back into the process,
and by that time, some point in time, you come forward
with a notice, if you like a mega-notice to proposed
Now, whether it's on specific regulations
or a new part to the regulations, I don't know. But
I think at the moment we're thinking about a new part
to the Code of Federal Regulations to deal with these
new types of reactor designs.
CHAIRMAN KRESS: For advanced reactors.
MR. HEYMER: Yes. Advanced reactors.
CHAIRMAN KRESS: Part 6(e) something or
MR. HEYMER: Yeah, 63.53 or whatever, yes.
MR. SIEBER: It seems to me that licensed
renewal never struck me as particularly risk informed
or performance based. How does that act of a proof of
MR. HEYMER: Well, in licensed renewal
there was a draft regulation, and then some plants
came forward, and one or two dropped out, and then
Constellation and Duke took up the ball, and there
were active interactions going on on renewing a
license, a specific license at the same time as we
were trying to work out the implementation details
associated with the regulation, and in fact, while the
regulation in some cases was being changed.
And so that's how I see it's more of a
process issue. I agree with you, it's --
MR. SIEBER: It's not risk informed.
MR. HEYMER: It's not risk informed, but
it's -- we're trying to look at the regulatory process
as well as the specific regulations dealing with that.
DR. APOSTOLAKIS: Adrian.
MR. SIEBER: Thank you.
DR. APOSTOLAKIS: Everybody keeps saying
risk informed performance based, but can licensing
really be performance based?
MR. HEYMER: I think in the context of
purely the licensing action, no, but what follows on
DR. APOSTOLAKIS: Oh, the regulatory.
MR. HEYMER: Yes.
DR. APOSTOLAKIS: The oversight, sure. We
are not dealing with that now. You are dealing with
licensing, aren't you?
MR. HEYMER: Well, we think that if you
put a new Part 63 in place that there should be some
element dealing with operational aspects, and so
that's where we see that coming in, and there's also
a probability that if you look at the Part 52 process
in ITAAC, that is akin to a performance based element
to a certain extent.
I mean, you have the ITAAC which are
Okay, next slide.
This is a pictorial representation of the
process that we've -- I've just discussed. I spoke
about coming down from the top, but equally you've got
the reg. guides and the specific design, specific
guides from the bottom and it's -- if you like, we
could have drawn it as a pyramid, but it was easier to
put all these words in place.
What are the safety areas and what is the
And we think they are the same as the
oversight process, and if you go to the next slide,
this is what the regulatory oversight process is as of
today. Does it cover everything in a regulatory
And the answer is, no, it doesn't. There
are some things missing, and I think if you start
looking at some of the advanced reactor types that we
have today, are we talking about mitigation systems or
And by that I mean perhaps there isn't a
system to mitigate the initiating event. Perhaps it's
designed into the plant.
There's also an admin. element that's
missing that would cover some of the reporting
requirements, configuration and change control, cover
And so if you go to the next slide,
please, this is what one might look like, and we
haven't had very much discussions totally within the
industry. There are rather a lot of boxes and it's a
very complex slide.
Some things I want to point out is I don't
think it's mitigation systems. It's mitigation in
general, and we need to perhaps define what that is.
And then under the administrative area,
you have a whole section of issues here, some of which
could be risk informed. Others, which will probably
just almost be lifted carte blanche out of a Part 50
space, and whether or not we do that is still to be
And one of the other issues is how would
we deal with the Part 52 interface. And I think there
is a way to deal with that as you go through the
rulemaking process with the conforming change.
But some of these, like the reporting
elements, tech spec amendments, and things like that,
I think there is an opportunity to risk inform those
I believe there is some internal work done
that showed that 40 percent of all tech. spec.
amendments aren't really associated with safety, and
something like 70 percent of all LERs and reporting
requirements from 50.72 and 50.73 aren't associated
with safety significant issues.
So I think that's something that we should
take a look at from an administrative burden that
perhaps we need to place the emphasis of our resources
As you go down here one other point is
that on radiation safety, we are looking at an
activity to take a look at Part 20 and see if we can
improve on that regulation, and perhaps make it
performance based, building on what we've learned over
the last 35, 40 years of implementing those
regulations within the industry.
So that is an addition to what we have
How long is this going to take?
Well, as I said, we're hoping to have some
recommendations or proposals into the NRC staff
towards the end of this year, early part of next year.
CHAIRMAN KRESS: Whenever I've seen this
slide or the previous equivalent, without the added
parts, I've always thought between that top box and
the three boxes below it, and now you have four, that
there's a missing set of boxes. And that is what is
the regulatory objective of reactor safety.
Is that the safety goals, for example, or
is it something else?
So what's the regulatory objective for
radiation safety? Is that 10 CFR 100 or is it -- and
similarly for the safeguards.
I've always thought that it's that missing
line in there that gives us a lot of trouble. And I
wonder if you guys had planned on adding something in
there to define what we mean by those three boxes, or
MR. HEYMER: Well, when you look at the --
when you look at the oversight process, there was an
attempt to define what is associated with those -- it
was three boxes, but those -- that second layer, and
associated with the attributes and an attempt to
define what they are within those areas, and as they
come down into the next box, which is the cornerstone.
We can take a look at that and see, but
that's a good input.
DR. APOSTOLAKIS: I had a similar comment,
maybe expressed in a different way. The fundamental
difference between what you're trying to do and what
the oversight process does is that the oversight
process starts with an existing system that has been
licensed and works with changes from that.
As such, the need for these goals that Tom
mentioned is not there because now, you know, I look
at the particular plant, look at the initiating
events. There is a certain rate. Although the system
is not plant specific yet, they're going there with
design specific thresholds.
But if you think about this framework
being used to license a new concept, then all the
questions that came up this morning during Mike
Golay's presentation come back here to haunt you.
In his presentation, Tom asked what is the
allocation to LOCA's of, you know, the goal and so on.
Well, here because you are starting with a new sheet
of paper, you have the same questions. How much
should I tolerate of the frequency to go to the
initiating events, to the mitigating systems, to the
So it's really something that's -- I mean,
I think you have very good intentions, Adrian, but the
really tough questions have not been addressed yet.
There is a fundamental difference between
overseeing something that's already there and has been
licensed and starting with something that's coming out
of the blue, and I don't know. I don't know what the
initiating events are for the pebble bed, you know.
MR. HEYMER: You make a very good point,
but it's not literally coming out of the blue. We
DR. APOSTOLAKIS: Well, it's maybe blue
MR. HEYMER: -- experience that we can
build on, and we can start establishing some of those.
DR. APOSTOLAKIS: I am sure we can, but
MR. HEYMER: I mean, I think if you sat a
group of people around a table you could come up with
those type --
DR. APOSTOLAKIS: I think what I'm saying
is that you are a little -- overplaying it a little
bit, unintentionally, the significance of the fact
that this framework has been used in the oversight
process. The fundamental issues are there.
If you look at the report the staff
developed on Option 3, essentially they follow the
same approach, but they dare go beyond that, and I
think you guys are a little cool towards the other
stuff they did.
If you look at what Golay did, well, it's
buried in there. I mean, it's the same idea. So I
think this is a good starting point, but I wouldn't
overplay the connection to oversight. It's a very
different regulatory problem. I guess, that's my
MR. HEYMER: That's good insight. It's
good input. I'm going to take that.
DR. APOSTOLAKIS: I came on too strong,
Adrian. I'm sorry.
MR. HEYMER: No, no, no. Please, please.
DR. APOSTOLAKIS: It's just that I don't
DR. APOSTOLAKIS: No, I'm sorry. No, I
didn't mean that. Take it back. Take it back.
MR. HEYMER: But from the cornerstones we
would develop specific criteria and specific
regulations, which would feed off the cornerstones in
those areas. And we did a -- what we just to see how
it would pan out, we looked at -- we took the current
regulations, of which there is about 160 general
design criteria regulations.
DR. APOSTOLAKIS: One other question.
MR. HEYMER: Yeah?
DR. APOSTOLAKIS: What we're seeing on the
board now on the screen is the NRC oversight. Now,
when you go to yours, you are adding a fourth element
in the second tier, but how about the bottom?
What happened to human performance, safety
conscious work environment, and problem identification
or resolution? Are you going to handle those in a
MR. HEYMER: Problem identification and
resolution is in the quality assurance element.
DR. APOSTOLAKIS: Oh, it's --
MR. HEYMER: Yes.
DR. APOSTOLAKIS: Oh, okay.
MR. HEYMER: And we see training would be
down in there as well. And so --
DR. APOSTOLAKIS: I see. So you are
covering those with the new boxes?
MR. HEYMER: Yes.
DR. APOSTOLAKIS: Okay.
MR. HEYMER: What we did is we took the
cornerstones, and we added a few areas to them, such
as administrative, financial and operational, and we
took the current regulations, and we attempted to say
which box would they fit into.
And we soon realized that some of them
actually fit into more than one box. That's why if
you add up the number it does actually come out to
more than 160.
But it's interesting to see where the
regulations are focused at the present time, and
perhaps that's quite proper because it's a legalistic
DR. APOSTOLAKIS: But again, why is that?
I mean, I appreciate the point you're making, but why
should I be surprised?
I mean, here is a technology that, you
know, the safety issues are really very low
probability, high consequence events. Very low
probability means that I really don't have a
statistical record, right?
So it makes sense for me to have lots of
administrative controls, doesn't it? Unless
administrative means something else that I don't
MR. HEYMER: Well --
DR. APOSTOLAKIS: Doesn't it?
MR. HEYMER: Administrative controls
dealing with reporting, dealing with how to make
DR. APOSTOLAKIS: Those I understand.
MR. HEYMER: -- dealing with how to update
DR. APOSTOLAKIS: So what you're saying is
we are -- we got them carried away?
MR. HEYMER: I think we may have done in
some areas. Now, on the other hand, if there's some
administrative requirements to keep the regulator
informed, I think the regulator should be informed of
those matters that have safety significance for the
DR. APOSTOLAKIS: Sure.
MR. HEYMER: And I think that's -- I mean,
when you look at some of the regulations and they're
ten pages in length and very complex and difficult to
read, it's certainly not nighttime reading. Then I
think we can do a job of streamlining those
regulations and still being able to focus on those
matters that really do present a risk to the public.
DR. GARRICK: And there are those
precursor events for which there is information and a
relatively high frequency.
MR. HEYMER: sure.
DR. GARRICK: And of course, the risk
informed is making the connection between those and
the events of interest.
DR. APOSTOLAKIS: No, I understand that,
but all I'm saying is that I'm not really surprised
that the highest number is down there in the
administrative thing, because you are dealing with
Now, I do agree that instead of 68
probably it should be 43. But I still think it's
going to be a high number.
MR. HEYMER: Yes, but hopefully not as
high as proportionally as what we've got here, and
plus also we recognize, as I'm sure you do, that the
current regulatory framework is not really that risk
DR. APOSTOLAKIS: No, no.
MR. HEYMER: And so it's fine. But it was
just to show you -- show us where it comes in and the
fact that we thought that it does fit.
On the next slide what we've attempted to
do, just as a point of discussion, is just to chalk
out, and we've done this for a couple of regulations,
is to calk out what might a regulation look like and
is some associated with configuration management?
And a lot of people in the past 20 years
or so have got into some problems about losing
configuration control and what that means in the
DR. APOSTOLAKIS: I must say --
MR. HEYMER: And that includes risk
DR. APOSTOLAKIS: I though your -- the
emphasis of your talk was going to be on licensing of
the new concepts. But yours seems to be attacking the
MR. HEYMER: It's a regulatory --
DR. APOSTOLAKIS: Does Exelon really worry
about how the NRC will regulate the pebble bed after
they get the license?
They worry about it right now?
MR. HEYMER: They worry about it right
now, but if you're dealing with -- and that's why I
said when you develop the framework, you have people
like Exelon moving out and testing the process on a
pebble bed, and there's a feedback process that comes
in and you can adjust.
Now, once you start operating those
plants, perhaps there's some additional -- just as
there is today. We get smarter as we go on.
DR. APOSTOLAKIS: So how is this different
from the current maintenance rule? Isn't that what it
MR. HEYMER: It's very little different.
DR. APOSTOLAKIS: Okay.
MR. HEYMER: I mean, it's just an example
of we're already there in some of these areas. Okay.
Now, some of the areas we're going to do some more
work, but it would be -- the purpose of this slide is
to say that it is not ten pages. It's a bit more than
ten words, but it's not going to be a detailed, very
specific regulation, like Appendix R, like 50.55(a)
for codes and standards.
We think it should be a fairly general,
high level sort of regulation that we're talking about
MR. SIEBER: Would this take the place of
MR. HEYMER: This could take the place of
MR. SIEBER: Well, this is pretty general.
MR. HEYMER: I mean, this is general. We
hadn't really thought that point all the way through,
but we thought if you're dealing with configuration
control, configuration management and change process,
if you're dealing with something akin to what we've
got in (a)(4) with the maintenance role, perhaps this
is all that you need.
Now, we probably need a few more bullets
than what we've got here, but as a starting point,
just to oil the brain up and get it moving, so to
MR. SIEBER: I would imagine that once the
lawyers got through that, it would look pretty much
MR. HEYMER: That's why we want a risk
informed and clean sheet approach, because we want to
be able to say, "Okay, is it risk management? Are you
managing the risk profile of the plant?"
And if you are, perhaps it's just
something like this in a reporting element. So it's
DR. POWERS: Can you tell me what exactly
your intention is? Assess and manage, what -- how do
you view those?
I mean, assess could be, yeah, it's a
MR. SIEBER: Tells you what desk drawer to
put it in.
MR. HEYMER: Underneath this there would
be a regulatory guide that actually defines the
specific process and would put the change control
criteria down in there. So it wouldn't necessarily be
in the regulation. It would be in the regulatory
DR. POWERS: The regulatory guides of
course are just advice to the staff. I mean, advice
to the licensee.
MR. HEYMER: And the licensee would make
DR. POWERS: He would make a commitment
MR. HEYMER: To have a process that
satisfies that reg. guide.
DR. POWERS: What I'm trying to understand
is what do you see him committing to do?
MR. HEYMER: Committing to meet the
regulatory guide, and as I said at the start, there is
a debate about how specific we get to, and I think
that point was made by Mike Golay, and I think it was
this morning about how specific do you get in items
such as the general design criteria, because when you
look at the general design criteria, they are very
motherhood statements and you could say, "Well, yeah,
this can fit any type of reactor."
Now, if you start getting the next step
below that, you begin to get more specific, and then
you begin to run into the different types of designs
and perhaps different facets of what is covered by the
regulations in those designs.
And so that's the reason why I put this
slide and the slide after it up, is to really
emphasize the point of what we're going to struggle
with, I think, as we go through this, is how much
detail you get into as you develop the new regulation.
DR. APOSTOLAKIS: The major challenge
right now, it seems to me, is licensing a new concept.
And you are really ahead of the game because -- not
ahead of the game, but you are looking after licensing
perhaps because it's easier to start with, because
it's very close to what we're doing now.
I mean as you said, this is very close to
what the maintenance rule is. So this is the easy
part and, you know, I also like to start with easy
MR. HEYMER: You go through and one guy
goes through and he has a license, but then you want
a standard by which other people coming forward can be
judged against, and this is what we're trying to put
DR. APOSTOLAKIS: But I think -- I
thought, at least, that you were going to place more
emphasis on the actual licensing process. How do you
risk inform that?
MR. HEYMER: Well, the licensing -- you
mean the Part 52 process or the Part 50 --
DR. APOSTOLAKIS: Yeah, if you want to go
PARTICIPANT: The design certification.
DR. APOSTOLAKIS: Okay, the design
MR. HEYMER: And just as Part 52
references Part 50, I think Part 52 would reference
this new process. I mean there's going to be a
comparison of -- as you come in, there's going to be
a comparison of the proof of concept project coming in
with what they believe should be the framework.
You've got the existing requirements, and you've got
the development of this new regulatory framework set
It's like a three cornered input, and the
initial comparison is going to be the new guy coming
in with the new framework, which is developed
predominately by that licensee, and which that
license's input would also feed into the general
And you've got the NRC with their current
regulations, and you want us to say you meet the
current regulations or take an exemption from them, or
you come up with another set of regulations. And what
we're looking at here is what do we come up with as
regards another set of regulations.
DR. APOSTOLAKIS: Again, if I look at --
I mean, if I look at the figure with the expanded
framework of the oversight process --
MR. HEYMER: Yeah.
DR. APOSTOLAKIS: -- I mean, all the
questions that came up this morning and yesterday,
again, you will need to a major effort to address
them. If I look at initiating events and mitigation
and barrier integrity and emergency preparedness, now
I'm told that in a new concept I really don't need to
worry too much about the containment, additional
I mean, I will need guidance to be able to
evaluate that in a risk informed way.
MR. HEYMER: I think the containment issue
is not necessarily linked to the containment. It's
linked to the -- it's linked to the barrier.
DR. APOSTOLAKIS: Yeah. The barrier. So,
you know, that's what I'm saying that I said earlier.
For an existing plant, I already have an allocation if
I were to use that way. We know from the existing
PRAs, 103 units and so on, roughly how much of the
risk is due to initiating event frequency, roughly how
much due to the mitigating systems, the containment,
and so on.
Now, in a new design somebody tells me,
"I'm going to keep the core damage frequency to ten to
minus five," which is, you know, maybe better than
some of your plants now. But all the ten to the minus
five comes from the initiating events. I'm going to
make sure that those don't happen.
Now I'm having a problem with defense in
depth, you know, which I didn't have in the oversight
process because the plant already existed.
Now, that's the fundamental problems that
will take time, I think as these, resolving those, and
some guidance from you guys would be great actually.
MR. HEYMER: As regards defense in depth,
you have -- I mean, that's linked to uncertainty in
the consequences, and you k now, the higher the
uncertainty and the larger the consequences, the
DR. APOSTOLAKIS: Right.
MR. HEYMER: And what we see is probably
more of a risk based and then a deterministic being
laid on top of that from a defense in depth
perspective as opposed to the other way around that
we've got it at the moment. We have a deterministic
set of regulatory requirements, and we're trying to
layer or at least impose a risk informed set on top of
DR. APOSTOLAKIS: I understand that. I
guess my point is that at this stage you have not
really attacked the most difficult questions of --
MR. HEYMER: Well, I think it comes
DR. APOSTOLAKIS: -- and that's fine, I
mean, as long as you agree that you have not.
MR. HEYMER: It comes back to the point
you made on the box diagram about defining what
DR. APOSTOLAKIS: I'm sorry. Comes back
MR. HEYMER: To the point you made on the
framework diagram that's got the admin. box in it
where you talked about reactor safety, radiation
DR. APOSTOLAKIS: Yeah.
MR. HEYMER: -- is defining, better
defining what those are.
DR. APOSTOLAKIS: Okay. So you will do
MR. HEYMER: Yes. I mean, we can do that.
DR. BONACA: Although I must say that I
still am confused about what's different in this from
the previous system. I mean I could take the previous
-- the existing system and then put it on --
MR. HEYMER: From a framework perspective,
not much. It's when you get down to specific
regulations you begin to see --
DR. BONACA: Okay. Well, I can understand
that. Yeah, all right. I don't quite understand from
the examples where the differences may be, and I
really couldn't figure it out. But I understand your
intent. I mean, clearly you said before that it has
to be risk informed and you're looking.
The reason why I bring it up is that we
saw a number of innovative processes this morning, and
the concern I have is that you can put in pricing
framework now that may stifle, in fact, the
credibility of some of the innovative cultures as much
as the old system stifles.
If you step ahead and make, you know, a
framework too articulated here. I don't know. It
seems to me --
MR. HEYMER: Well, when you look at the
framework and you see the current regulations and
requirements, I would agree with you.
If you look at the frame work and say
there are alternative regulations or a different set
of regulations, a different set of design criteria, I
think that gives you the flexibility.
If you go to the last slide, this is one
we came up with protection against natural phenomena.
I mean, it really brings home Mike Golay's point.
It's how specific do you get because this is almost
identical to what's in the general design criteria
But do you break it down into separate
elements or do you stay with a simple general
statement like this?
And that's one of the things I think we're
going to struggle with, but when you look at you're
going to protect against natural phenomena, I mean, I
think that's what you're going to have to do.
DR. POWERS: But it's the historically
reported. I mean, this is --
MR. HEYMER: Well, that's the reason why
initially we were going to stop at halfway through it
where it says capability to perform the safety
functions, and then we added on the last of it to say,
you know, do you go back to the historical or is it
just probabilistic or what, and that's the reason why
we put the last bit in.
DR. POWERS: What it means is that sites
where there hasn't been anybody living or reporting
for have much less severe criteria than where I have
a long history.
MR. HEYMER: It depends on how far back
you go. I mean, a lot of those histories go back
before a nuclear plant was actually put in place.
DR. POWERS: Sure. I mean, I'm think of
earthquake. We go back farther than that.
MR. HEYMER: Oh, a lot farther, yeah.
DR. POWERS: And so why now are we going
to drop it down to just the historical record on
earthquakes? There's not enough history to get any
kind of statistics on just earthquakes.
MR. HEYMER: Well, I mean, that's a debate
that I think we're going to have, but it's just to try
and highlight. The reason why we wrote it this way is
just to try and make the point of are we going to go
DR. APOSTOLAKIS: I can't remember right
now, but how is this different in a fundamental way
from the existing practice regarding earthquakes?
MR. HEYMER: We didn't say it would be
that much different.
DR. APOSTOLAKIS: This is almost the same,
is it not?
MR. HEYMER: Yes.
DR. POWERS: No, no. If I have to adjust
to use the historical record on earthquakes?
DR. APOSTOLAKIS: They define the safe
shutdown earthquake using the history of the site,
using the history. That doesn't mean you go strictly
by what happened, and they say, you know, you're going
to have what, a margin for uncertainty and so on?
It's really no different.
DR. POWERS: I think it's a big
DR. APOSTOLAKIS: Oh, no.
MR. SIEBER: The flood area --
DR. POWERS: If I have to live on what's
historically reported rather than the history of the
site, that's a big difference.
DR. APOSTOLAKIS: Oh, oh, oh, I see.
MR. SIEBER: The flood area is quite
different. For example, I know of one plant where
they postulated the breakage of a major upstream dam
to define what the flood level would be, and of
course, there's no historical record that that dam
So, you know, that prevents you from
postulating that might occur, but have not yet
occurred as part of the protection of the plant.
DR. APOSTOLAKIS: And what safety
significant -- do you mean risk significant --
MR. HEYMER: Yeah.
DR. APOSTOLAKIS: -- in the sense of
MR. HEYMER: And the reason why I put that
down is because when we told -- we mentioned about
safety related or safety --
DR. APOSTOLAKIS: Significant.
MR. HEYMER: I know. We were just -- we
put safety significance trying to emphasize that
that's in tune with the Option 2/Option 3 type of
Now, you could say risk significant in
terms of the maintenance rule. It would come up.
DR. APOSTOLAKIS: No, there is a slight
problem here, I think, in the sense that I cannot
determine what is risk significant or safety
significant until I have a PRA which will tell me when
the PRA will be based on the actual design, but now
I'm supposed to use the results of that PRA, in fact,
to create the knowledge base for the PRA.
MR. HEYMER: Well, it's an iterative
DR. APOSTOLAKIS: So you start with one
and do it and do it again?
MR. HEYMER: Yeah, and there is
experience. I mean, when you do -- you know.
DR. APOSTOLAKIS: Well, yeah.
MR. HEYMER: You just don't say, "Well,
I'm starting with a new design. What have I got?" I
mean, there's --
DR. APOSTOLAKIS: I must say overall
though, Adrian, maybe it's too early in the process,
but I, frankly, thought you were going to come up with
something that's a little more daring. You are really
sticking to the existing regulations which you have
blasted in the past. We must be doing something
DR. APOSTOLAKIS: You really like it.
MR. HEYMER: But there is specific
language in the regulations.
DR. GARRICK: There is one big difference,
DR. APOSTOLAKIS: What is?
DR. GARRICK: -- that I am detecting, and
I think it's one of the things that bothers you, and
that's the issue of allocation. I get the impression
that they're talking more in terms of general
performance goals and not so much in terms of
allocation down to levels that partition those or
apportion those to lower levels of the plant.
DR. APOSTOLAKIS: I think whether they're
DR. GARRICK: And that's a big difference.
DR. APOSTOLAKIS: No. I think what they
are doing is they are not facing it. The issue will
come up, eventually will come up. You don't have to
allocate, but de facto by doing the things that
presumably they will propose, you will have an
allocation, and the question will be a petition, if
you want. Is that good enough?
Because if I go back to the boxes, again,
if they come back and tell me that all my eggs are in
the initiating event basket, why? Because this is
what the various criteria produce. What am I going to
do as a regulator? Am I going to accept that because
that's how it turned out, or what?
I know that you have an aversion, John, to
allocating risk from top down.
DR. GARRICK: Right.
DR. APOSTOLAKIS: And I appreciate that,
but I think at some point you have to -- I mean, let's
say you go purely by engineering and you build
something because it's feasible. You have to decide
whether the design is acceptable, which in some sense
brings that issue back into the forefront of --
DR. GARRICK: I'm not saying you shouldn't
strive for a balanced design. I'm just saying that
there are two ways of looking at this. One is if you
really are trying to implement a risk informed and
performance based approach, then you can take that at
an overall performance and an overall risk level.
You're got a risk standard and a
performance level, and you go after it, and another
way is to give it more of a bottoms up treatment.
And it's more difficult, especially when
you're talking about different designs, to think in
terms of an allocation process.
DR. APOSTOLAKIS: And I agree with you.
I fully agree.
DR. GARRICK: It just will not make sense,
DR. APOSTOLAKIS: Exactly.
DR. GARRICK: -- it won't work.
DR. APOSTOLAKIS: I think it should be a
check at the end whether you really -- allocation
really means difference in depth if you want to think
about it that way.
DR. GARRICK: Okay.
DR. APOSTOLAKIS: It's not something that
should drive you. It should be a check of, you know,
the design, whether you like what you see.
But I must say I'm really surprised at how
little the current proposals differ from what we're
DR. GARRICK: Maybe this will stimulate
them now to go back and be more daring.
MR. HEYMER: On that point, you know,
we've given you today just what our very first initial
DR. APOSTOLAKIS: And I fully appreciate
that. Maybe some of my comments are unfair.
MR. HEYMER: Oh, no.
DR. APOSTOLAKIS: But they're more fun
MR. HEYMER: It's good input, you know?
And we've got to get the input from a lot of other
people in the industry, and once we've got that, you
know, I'm sure we're going to have the opportunity to
come back and discuss it with you again.
DR. APOSTOLAKIS: It's probably pretty
much a reality, but you got the first reaction though
MR. HEYMER: And really and truly, you
know, if we take a look, we've often said, at the
regulations at a high level, there's a lot of good
words in the existing regulation. There's also a lot
of words in there that give us heart burn, and what we
think is that we need to go in there and streamline
and sort them out.
MR. SIEBER: I think though that part of
the reason the regulations are written the way they
are today is that they're supposed to be enforceable.
You know, this is really the law, and when you get too
fuzzy and wishy-washy about things, you can't enforce
it, and if you can't enforce it, there's no point in
having the regulation. You might as well just call
them suggestions at that point.
MR. HEYMER: That's an idea.
DR. APOSTOLAKIS: Just a general
DR. POWERS: And there is a --
CHAIRMAN KRESS: We have a comment from
DR. POWERS: -- a discrepancy in the way
engineers treat quantitative views and the way the
legal group treats quantitative definitions, and quite
frankly, we have to accommodate them. They don't have
to accommodate us.
MR. SIEBER: That's the way it goes.
DR. POWERS: Yeah.
MR. SIEBER: That's just the way the world
DR. POWERS: And they accommodate it by
not, by avoiding the quantitative and using case law
to get precision in the definitions.
MR. SIEBER: That's right.
DR. POWERS: We seek precision through
numbers, and they seek it through cases and live with
DR. KADAK: Let me suggest -- this is Andy
Let me suggest something a little more
daring, and it's reestablishing the regulatory compact
between what the regulator's job is, what the
licensee's job is in terms of how they deal in terms
of the future protection of public health and safety
from a system that is quite prescriptive in terms of
its requirements to something that more fully puts the
burden on the operator to meet some what you might
call high level goals.
And I'm not sure what that new
relationship is, but clearly if we go to 1,000 plants,
let's just say, in trying to build on George's ten
times whatever the probability is and it gets to be a
large number, that you can't continue doing it the
same way, and what new regime might be appropriate to
protect the public health and safety in the sense of
a risk informed and performance based system.
So that addresses the inspection and
addresses the enforcement action, as well as the
standards that you apply to new technology. So that's
kind of the comment to the NEI people as well as to
the rest of us, and that is how can we improve the
overall process not only for design and construction
and operation, but also regulation.
So a though. If there was a question on
that, you can try to answer it, but it's a new
DR. APOSTOLAKIS: But you are going the
other way. I mean I get the impression from NEI that
they really don't want to move too much -- to far away
from the existing system. Perhaps it's the fear of
Another Option 2 review of the times
three, you know, and you are going about -- you're
talking about revising the whole structure and doing
all sorts of wonderful things. There must be a golden
optimum in the middle somewhere there.
MR. HEYMER: Yeah. It's thinking ahead
and saying, like just challenging the NRC relative to
how are they going to do license renewals for 80
plants in the next five years or ten years. They
can't something has to change, some trust, some new
relationship, and we have to figure out how that will
work in a legal way.
DR. POWERS: Well, I mean, I think they
came up with a fairly effective solution.
DR. APOSTOLAKIS: Which is?
DR. POWERS: I mean, they've gone through
the catalog to a variety of data on the agent
degradation, a huge number of topic reports that run
four or five pilots, established a template, and
people were following the template, and based on what
we saw from A&O, you follow the template and you put
out a pretty good product, and it goes very quickly.
DR. APOSTOLAKIS: The problem is that for
licensing new concepts, we don't have a template.
That's the --
DR. POWERS: Well, you're also not going
to have 80 new concepts in five years. We haven't got
the same problem.
CHAIRMAN KRESS: We could almost review
every one of them as a special case.
DR. POWERS: I mean we do each one of the
certifications in this special case because they are
special cases. Just a thought.
Now, if you had these 500 modular units,
then templates work very well.
DR. APOSTOLAKIS: Then I would have a
problem with the goals. The moment you get above 600,
I'd have a problem with it because the goals are posed
in terms of rates, and the rate inherently depends on
how many of those things you have. Okay?
So if somebody says, "Boy, this is the
dawn of the new nuclear era. We're going to build
another 1,000 reactors," we'd have to go back to the
Commission and ask them to think again about the goals
they have set.
DR. POWERS: Again, they'll tell us no.
CHAIRMAN KRESS: How does the prompt
fatality have anything to do with the number of
DR. APOSTOLAKIS: Oh, don't ask me
DR. POWERS: George, I think Tom hits upon
DR. APOSTOLAKIS: I think the societal
CHAIRMAN KRESS: Of course it does, but we
have no societal risk goals. That was my point.
DR. POWERS: The guy at the boundary, with
few exceptions, is only susceptible to one plan.
CHAIRMAN KRESS: That's right. We need
some societal risk though, which would change with the
number of plants.
DR. APOSTOLAKIS: That's right.
CHAIRMAN KRESS: We don't have them.
DR. POWERS: I don't know that. It's not
transparently obvious to me that you need a societal
CHAIRMAN KRESS: Well, I think if you had
1,000 plants --
DR. POWERS: I think we'd be much happier
if we had one to land contamination and injuries.
CHAIRMAN KRESS: Well, those goals in my
mind are societal type goals.
DR. APOSTOLAKIS: Those are societal.
CHAIRMAN KRESS: Those and total deaths I
would call societal goals.
DR. APOSTOLAKIS: Yeah, yeah. Anyway, are
we done with Adrian?
CHAIRMAN KRESS: Yeah. Thank you very
At this point I'm going to declare a 15
minute break, and then we'll start a very interesting
panel discussion at four o'clock.
(Whereupon, the foregoing matter went off
the record at 3:43 p.m. and went back on
the record at 4:02 p.m.)
CHAIRMAN KRESS: Let's get back to order,
This should be very interesting. I
haven't worked out any particular protocol of how to
proceed with this. What I think I'll do is just say
if any of you members of the panel wish to make some
comments before we entertain questions, why, you're
welcome to do so. You don't have to.
I don't think I like the idea of going
you, you, you, you make your comments. So I'll
actually open the floor. If any of you guys want to
make a few comments, just go ahead and volunteer and
we'll hear them and we'll through the floor open for
questions while you're commenting and after you
So if that's agreeable to you guys, we'll
do it that way. So with that I'll say who wants to
make some comments. Anybody?
Rich, go ahead and start.
MR. BARRETT: Let me just say -- is this
on? -- that in the material that we got in preparation
for the workshop, I think all of us were sent
questions that we were to deal with, and we were asked
to make a few points about the question that reads as
DR. APOSTOLAKIS: I can't hear you. Can
you move the microphone closer?
MR. BARRETT: The question that we were
faced with was this one. What are the most important
regulatory challenges for the licensing of future
nuclear power plants?
And I think the guidance we were given was
that we should try to keep it to a list of three or
four, and I see everyone shaking their heads that you
all got the same question; is that right?
PARTICIPANT: We may not have done our
MR. BARRETT: All right. Well, at some
point I would like to answer the question. Maybe I
ought to go first and that would get everybody else
thinking. How's that?
CHAIRMAN KRESS: Sounds like a good way to
MR. BARRETT: Okay. Well, you know, from
the staff's point of view I think you've heard on a
number of occasions how the staff defines success, and
we define success whether it's in licensing or in
operating reactors in terms of the four pillars that
we have defined for operating reactors.
And when you're talking about the
licensing of a future reactor, I think you're dealing
with the same four pillars, except that you probably
want to state them a little differently.
So let me simply state those four pillars.
First of all, I think what we want to do is make sure
that we assure safety as opposed to maintaining safety
for the operating plants.
And, secondly, that we want to do that in
a way that is effective and efficient.
And, thirdly, we want to do this without
imposing unnecessary regulatory burden upon the
And finally, the fourth of these pillars
is to do this all in a way that instills public
confidence in the licensing process.
So those are the four pillars that we use
for judging success of anything we do, and so keeping
in mind those four pillars, I'd like to just say a few
words about what I think are the most important
regulatory challenges for licensing of future nuclear
First of all, to maintain safety or to
assure safety, we're going to have to take a
comprehensive look at every aspect of safe design and
operation, including the risk implications of these
Now, we're going to have to do that, and
in order to do that, and I think this is a very
important point, we must assure that the NRC has all
of the requisite skills to do a complete review, and
that's a big challenge for us because this is going to
require a significant effort on the part of the NRC to
retain our current experts and to recruit and to train
So I think that's the first thing that's
required from the NRC's side.
Secondly, to assure efficiency and
effectiveness, we're going to have to streamline our
review of siting and licensing applications, and we're
going to have to take a careful look at the time and
the resources that are required for those reviews.
And I think that that's a management
challenge. I think we've seen that challenge being
met in the management of the license renewal
applications, and our challenge is to do that also in
our management of the applications for review of
On the other hand, applicants for site
permits, design certifications and combined licenses
must submit complete applications of high quality.
That's an absolute must if we're going to be effective
and efficient, and the applicant furthermore has to
assign the resources necessary to respond promptly and
completely to staff questions.
So to assure effectiveness and efficiency
in licensing, there's a burden on the staff, and we're
prepared to go forward and meet that, but there's also
a burden on the applicant to assure that you bring in
that application, make a complete, high quality, and
support it from start to finish.
The third bullet is avoiding unnecessary
regulatory burden, and in order to do that, I think
that we must bring out early resolution of a lot of
the issues related to our regulatory process. In
these last two days, you heard a lot of examples of
these types of issues. Some of them are financial.
Some of them have to do with ITAAC. Some of them have
to do with the processes that we use. Some are
specific to modular reactors and merchant power, and
some are bought up because we have new designs.
We're going to have to get early
resolution of these questions in order to avoid
unnecessary regulatory burden on applicants.
And, finally, to instill public
confidence, we must assure that all of our
stakeholders have access to the licensing process and
input to the licensing process, and this is a
commitment that has to start at the very beginning and
has to be carried on throughout the process.
I think yesterday and today this workshop
is a very good start along those lines. I want to
point out that the staff is going to sponsor a
workshop at the end of July in which we are going to
be looking for stakeholder comments on a wide variety
of regulatory issues that will be important as we go
forward as well, and we're committed to instilling
public confidence by giving people access to the
So those are the four areas that I think
are important for licensing of future nuclear plants.
DR. WALLIS: Well, Rich, the only one
comment I'd have is it's not good enough just to have
access to a process. What they find there has to
instill the confidence that you're trying to instill.
MR. BARRETT: Right. One of the things
that we wanted to do at the workshop is very early on
we want to identify where specifically, to the extent
possible, where people's concerns are about the future
licensing so that we can factor those concerns in at
every stage along the way and make sure that we
address those questions and concerns.
CHAIRMAN KRESS: I think what I'll do is
after a given panelist makes his talk, I'll open the
floor for questions if anybody wishes to question that
particular panelist while it's fresh in your mind, and
when we exhaust those questions, which we may have
already, we'll move on to another, I guess, volunteer.
I don't want to put anybody on the spot,
but does anybody want to speak next? Mr. Lyman, are
MR. LYMAN: I actually prepared slides.
CHAIRMAN KRESS: Well, that's certainly
MR. LYMAN: And that's probably more
CHAIRMAN KRESS: No.
MR. LYMAN: -- you need, but --
CHAIRMAN KRESS: No, that's fine.
MR. LYMAN: -- I can go through them
DR. TODREAS: Don't worry because I did,
CHAIRMAN KRESS: That's fine. That's
fine. I think that's probably a good way to do it.
MR. LYMAN: Are you going to go first?
DR. TODREAS: No, no. You spoke up first.
You get the floor.
PARTICIPANT: Well, let me change these.
DR. TODREAS: Well, let me go first since
CHAIRMAN KRESS: Well, since there's a
palpable reason, we'll let --
DR. TODREAS: She's got the order. That's
fine. Just flip it up.
CHAIRMAN KRESS: Why don't we go in the
order of the agenda then? How does it read?
PARTICIPANT: That will help Jenny.
CHAIRMAN KRESS: Yeah, it'll help her.
We'll do it that way. We'll go in the order that the
agenda has those listed.
DR. TODREAS: I'm first.
CHAIRMAN KRESS: Okay. This is the second
DR. TODREAS: Okay. Just go to the first
What I did since you want to constrict it,
I picked out an area, which is basically fuels and
materials, and actually the theme is somewhat similar
to what you just mentioned. I'm going to wind up
getting back to the NRC is going to have to have a
confirmatory research base and is going to have to
have people who know the material, can deal with
material, can ask the questions.
It's going to come from the fact, and I'm
building on what I did this morning, that we're
dealing with fuel cycles, and I'm talking about these
Generation IV plants now. I'm in the 2010 to 2030
period. I'm not talking about the near term
deployment water plants based on the one through
cycle, but I will get into the gas plant.
CHAIRMAN KRESS: Who should do these
DR. TODREAS: Well, obviously industry has
got to do the research as a base, and then the NRC to
a certain degree has got to do enough confirmatory
research to insure that they've got a complete
database for their education and to confirm to the
We've been through, you know, a lot of
that with the research program.
DR. POWERS: But that's the rub, is
knowing how much and when to do confirmatory research
because, I mean, there's finite resources here, and
there are constraints on the system.
DR. TODREAS: What I'm telling you is to
get on fuels and materials. Make it a good part of
DR. POWERS: We never had any materials
DR. TODREAS: And what I heard Chuck --
I'm glad that under number two here I mentioned
coolants because we can get off into coolants, but
we're going to go to longer cycles. We're going to go
to higher temperatures, and since I was limited to
actually two to three challenges, I just stuck four
down here as a -- this is kind of an outcome.
DR. POWERS: That provokes the question:
is it because you're from MIT and can't read?
DR. TODREAS: Can't count. Yeah, that's
the supermarket checkout joke, but I'm only going to
talk about the two that are starred, but you know, if
we go to nuclear power in a significant way, we're
going to have to deal with waste volume, and we're
going to have to reduce the toxicity.
I'm not really talking about accelerator
trends, mutation relative to toxicity going all the
way, but you've got to start to think about somehow
separating out certain isotopes and going more toward
the French direction of a dedicated program on volume
reduction and focused on toxicity.
We're also going to have to get into
coolant corrosion aspects. I never met formally Peter
Ford, but I know through my colleagues he's really
been into white water coolant corrosion issues, and
these other coolants, no matter what we say about
them, are going to have impurities in them. We're
going to learn things. We're going to have to go
through the whole coolant corrosion business.
But what I wanted to get to was three and
four. We're going to deal with new fuels, and the
first new fuel effectively that we're dealing with is
particle fuel, and particle fuel for me, I can see
applications not just with gas reactors, but particle
fuels in different matrices can be applied in broader
So I'm very positive on potential for
particle fuel, but with core loads of billions of
these particles, how are you going to deal with them?
Well, if you go to the next figure, the
next figure shows my problem. What I've got here is
basically a sample list of questions that I drew up
about a year and a half ago and have been talking from
The first list, these are the types of
things I'd go into relative to particle fuel. The
first set of questions basically deal with the source
term in terms of circulating, possible circulating
The second two sets of questions are
focused on whether our fuel particle is going to be
qualified by a product or a process specification, and
I don't know the answer to that yet, but if it's a
product specification, we've got to do a hell of a lot
of work because we've got to identify those attributes
and those combinations of attributes that have to be
controlled to certain levels, and we have to do it
relative to the fuel design that we're up to.
CHAIRMAN KRESS: Are you just saying you
can't know that the particle has been failed until
after you stick it in the reactor and irradiate it so
that you've got some signal that says you have failed
particles. Is that --
DR. TODREAS: No, what I'm saying is it
may be the same, but we're going to run a core filled
with these particles, and we're going to say always
that it can sustain a depressurization accident.
Well, what are the attributes and what's
the tolerance around those attributes of particles
that can be in the core that with burn-up that can
sustain that transient? Ask that question and see
what answers you get.
That's what you're going to have to know
to go on a product spec.
If you go on a process spec, then you've
got to be sure that the fuel that you're going to put
in that reactor has been thoroughly enough tested, and
the fuel that has been put in the reactor, how it's
been fabricated is the same process that the tests
were all done on on the fuel.
So that imposes or requires quite a long
test program. So, say, on the pebble bed reactor,
you're going to have to go back to that German fuel
really to know what the process was and make sure you
duplicate that process because presumably that's what
the test base is on.
If you go to the third figure, I think
we're moving toward a process spec, and if we do, what
I see is we have replaced or at least made the fuel
fabrication facility operator analogous to the current
control room operator, and you're going to really have
to have the fuel fabrication facility locked into the
whole operation process, which is quite different than
what we do now with the product spec on light water
And also, if we go to a process spec, once
we freeze the process it's going to be difficult to
make changes, really costly to make changes, maybe not
so difficult, because every time you deal with the
process, you're going to have to go back and requalify
CHAIRMAN KRESS: This is somewhat
analogous to the dilemma we face with digital INC
controls where we don't determine the reliability of
the product, but we control the process at which the
software, for example, is put together.
DR. TODREAS: And my anecdote here is I
took the relevant people to Gillette about nine months
ago. Gillette has been making razor blades for 100
years. They make billions a year. They do it through
a process spec.
They wrote a paper about a year, year and
a half ago. They had a problem in one of the
processes. It was the washing process where they
washed the blades before they put on a coating, which
is the coating right on the tip of the blade that
gives it hardness, the ability to cut.
And so they had a problem and they lost
the process control. They didn't know why. It turned
out the reason they did, being Boston, they left the
soap out on the loading dock. The temperature
dropped. They didn't know it froze. They pulled it
out, put it in the process, and the process didn't
So that's indicative of the real control
and scope you've got to have if you've got a process
The other point I want to make -- I see
I'm running a little long, but the next slide.
If we go with this fuel, this long cycle,
implicit with that is we're going to try to match the
maintenance cycle with the operating cycle, and when
we do that, we're going to really reexamine the
maintenance approach, extend those aspects where we
can after a good technical look. If you can't extend
the interval between maintenance, you try to do it on
line, and if you can't do it on line, you try to
change the practice by design and bringing in new
component design, new systems.
And I've basically got an example of
relief valve testing that we've developed associated
with IRIS because IRIS would try to go to a long
cycle, and relief valve testing, very difficult now to
do it on line. It's going to have to go through a
code case, but we've come up with a relief valve
system that I think could possibly do it.
But the point I wanted to make when you
can finally come down to adjustments in the practice.
So finally, last slide. Why are these
items challenges? And then I come back to the point
that was made. In the fuels and materials and coolant
corrosion area, you're going to need to develop the
NRC staff expertise. Develop it, hold it. The real
strength of this place is that smart people can ask
the right questions, and we really get off base if
people don't ask the right questions in terms of
getting technically focused on what's important, and
you need this confirmatory research base.
And then finally, the last bullet at the
bottom just goes back to what we talked about on this
risk based regulatory framework, and I really look
forward to NEI picking that ball up, leading, and
giving us something relative to these new reactors
because we're going to have new coolants, new systems,
new fuels, and we're going to have to take advantage
-- I look at that -- take advantage of the
opportunities when we go to new systems to open this
But you guys are going to have to take the
lead with a structure that goes through these guys and
satisfies them and has a good dialogue.
CHAIRMAN KRESS: Thank you.
DR. GARRICK: One of the things that
bothers me about these challenges is the resource
base, the talent, because we are talking about fuels
quite different from anything we have been dealing
with. We're talking about thermodynamic conditions
quite different than anything we've been dealing with
The government is not known for its
ability to change people in and out efficiently and
effectively, and yet the whole regulatory process is
founded on technical expertise because it can't be
automated, except up to a certain point.
So isn't that a real problem in coming to
grips with these new technologies?
DR. TODREAS: Well, that's why I raised
it, because I'm hopeful that the ACRS will find
reverberations through it, but I mean, that hasn't
gone unrecognized at all in this building. I'm just
looking behind Graham Wallis and Ken Rogers is there.
When I was involved with the research oversight, that
was one of the whole points that he raised, the
competence or the requirement to maintain and enhance
the competence of NRC.
I don't exactly know where it's gone over
the last two or three years and whether it's a
problem, but I know in fuels, fuels in particular, we
got so much -- you know, we weren't pushing the burn-
ups very much. We had a fixed fuel system. There
weren't many issues in the research side. The number
of people really knowledgeable and working in fuels
was reduced just because there wasn't a demand.
Now not only are we pushing light water
reactor fuels up, but we're going to bring in SURMETS,
METMETS, et cetera.
DR. POWERS: Let me take a devil's
advocate position on that and just reason a little bit
DR. TODREAS: Go ahead.
DR. POWERS: When we look at reactivity
excursion accidents in the current generation of
plants, we typically find them to be a very localized
phenomenon. It's fairly challenging, in fact, to
imagine any of the probable reactivity excursion
events like a control rod ejection.
And when I say "probable," something
greater than ten to the minus sixth, say, probability
leading to a core-wide event that results in any
When I look at these modern reactors,
maybe there are more adventurous things, but by and
large, I would say reactivity events are going to be
relatively small sorts of things compared to loss of
coolant, loss of heat sync accident.
I guess I'm asking the question: why
should we get involved in fuel? Why don't we just let
that be the licensee's problem? He's the one that's
got to take care of his work force. He's the one
that's got to take care of this plant and his fuel and
really draw our boundary and say what we're really
interested in is fission product release that goes
outside the plant.
DR. TODREAS: Yeah, but don't just start
off with reactivity accidents. Start off with
operational reactor behavior and failed fuel and --
DR. POWERS: Let that be his problem.
Coolant activities, start-up problems, things like
that, it doesn't impact the public health and safety.
So let him worry about that for his purposes.
DR. TODREAS: Okay. The only answer to
that when you come back, that is his problem.
Fundamentally the licensee is responsible. He's
responsible for everything, but if you've got a
regulatory agency or you're got a development agency
in DOE, the best regulator and the best developer in
DOE is a smart customer because they don't waste your
time on putting you on the wrong questions, and they
don't waste dollars going out and developing the wrong
So it's just a question that I have the
belief that government ought to have the best people
they can, and they need competence to interact with
the guy who owns the problem.
DR. APOSTOLAKIS: I also think, Dana, as
you know very well, if we start regulating that way,
we're not satisfying or meeting the fourth pillar that
Rich Barrett mentioned, public confidence. If you
start having incidents that affect the core but do not
end up releasing anything, I don't think the public is
going to trust us very much, and that's why you have
the cornerstones in the oversight process that include
I mean you can argue there it's none of
our business as long as there is no core damage or as
long as there is no release, it's not our business,
and yet the agency says, no, it is our business.
DR. POWERS: And what I'm saying is why.
You're saying it's a public confidence issue?
DR. APOSTOLAKIS: Yeah, it's a public
CHAIRMAN KRESS: I would think there's a
strong reason than that.
DR. APOSTOLAKIS: I don't think it's weak.
CHAIRMAN KRESS: I would think there's a
stronger reason than that, Dana, and that is you want
to -- one of the principal performance indicators, for
example, is that you want them to be something that
tells you that things are wrong, but they're not
approaching a catastrophic condition yet, and then
similarly, if you put the regulations here, you want
to regulate to a level that, for example,
radioactivity in the primary system, if it's a gas
You want to say, okay, this is indicative
of some level of failed fuel, and even though if I
release that, it may not hurt the public, but I'm not
sure that if I ever undergo an depressurization
accident it may not have something equivalent to the
iodine spike, and it may be too much. Maybe I should
regulate to some level that's short of hurting the
public if it gets release.
That would be my --
DR. POWERS: I mean, I can -- all right.
Suppose you came along and said, "Okay. You run your
-- just make sure you coolant level is such that you
never come within ten percent of the 10 CFR 100
CHAIRMAN KRESS: I would buy that if they
also included some factor of safety to take care of
the spike like concept.
DR. POWERS: The fact of the matter is
we've never found any relationship between coolant
activity and risk to the public health and safety.
CHAIRMAN KRESS: But you might if you
didn't have a containment.
DR. POWERS: We'll always have a
CHAIRMAN KRESS: Oh, okay.
DR. POWERS: Remember Moses with the 11th
CHAIRMAN KRESS: Yeah.
DR. APOSTOLAKIS: This is not a Committee
position. This is a personal view.
MR. HOCKRITTER: I was going to ask Neil
something, but let me just also respond to Dana.
I was going to say the same thing. Some
of these designs are looking at not having a
containment, and then I think you have issues.
Today in the light water area, really
failed fuel is a utility or an operator concern, and
it's a vendor concern, and you're very, very careful
about it because obviously if you want to sell fuel,
you don't want it to fail. So it's a problem that
But you've got a containment around the
plant. In some of these designs you don't have a
containment, and I think it could be more of a
DR. POWERS: Made an awful good argument
for having a containment, didn't you?
MR. HOCKRITTER: Back to Neil, on your
process control, are you envisioning a control process
where you can try to control each, on these particles,
each layer in this thickness within a specified amount
or the total product as it comes out?
Because I don't see how you control each
layer, and if you control on the total product that
comes out, if it doesn't come out right, and you won't
find that out probably until you operate, then you've
got a problem.
DR. TODREAS: Okay. First, let me answer
I'm not promoting either a process or a product. What
I am doing is asking whether it is going to be a
process or a product, and then developing a line of
questioning along each.
MR. HOCKRITTER: Either way.
DR. TODREAS: However, now, in addition
though the way you ask the words, a process spec means
that you control the process of every manufacturing
step. So you may have a process where you're doing
the coating, but you don't go and measure the coating
or sample the coating. What you do is you control the
attributes of the fabrication process.
MR. HOCKRITTER: Well, how do you know you
meet your criteria if you don't go and measure?
DR. TODREAS: No, no, because what you do
in the qualification stage, you take the product that
comes out; you put it in the reactor; and you'd better
make damn well sure it can take the burn-up with a
failure criteria over whatever your design length is.
MR. HOCKRITTER: Yeah, but at some point
you're going to have to have gone through and verified
that whatever your process is gave you the product
that you wanted.
DR. TODREAS: Absolutely.
DR. APOSTOLAKIS: There is indication or
evidence that the process is working well. That's
different from having a product based method for
And it's the same thing with software as
Tom said. I mean we are largely controlling the
process now, but then we know if we're going to put it
there in the field and it starts failing that
something was wrong with the process.
DR. TODREAS: Larry, there's a tremendous
amount of radiation data on this particle fuel. If
you can pin down the process that it was made to and
link it to the data, then you can say you identified
the process, and then you can basically duplicate it
and keep going. That's the burden the applicant is
going to have.
DR. APOSTOLAKIS: Yeah, I agree with you
it's late, but it's not a matter of choice really,
process versus product. You're forced to go to the
process because you don't have the tools to do the
other one. So it's -- you know.
DR. TODREAS: Why do you say you don't
have the tools?
DR. APOSTOLAKIS: Well, take INC, for
example. They know a little better than fuels. Right
now nobody knows what kinds of tests you should do to
a new digital system to assure that they will perform
out there. So it's a combination of controlling the
process of producing the software, and of course, you
do some tests, as well. But this envelope --
DR. TODREAS: Okay. I might not be
surprised if an applicant comes in and says, "I know
what the thickness of the various layers have got to
be within a certain spec. I know what the impurity
levels are that need to be controlled."
You may be a case on fuel that way.
PARTICIPANT: You're going to need that to
get an analysis. You're going to need that
information to do the analysis.
DR. TODREAS: What was asked for is the
DR. APOSTOLAKIS: Right, right.
DR. TODREAS: Okay? That area is --
DR. APOSTOLAKIS: It is certainly a
CHAIRMAN KRESS: Okay. With that, let's
move on to the next speaker, which according to the
list here would be Mr. Lyman. Are you prepared or are
you over there tying your shoe or what?
MR. LYMAN: No, I was looking for more
evidence to demonstrate the previous discussion.
CHAIRMAN KRESS: You're welcome to go
ahead and look.
MR. LYMAN: No, that's okay.
DR. POWERS: I'll pull out. I see you
guys can't see directly.
CHAIRMAN KRESS: Okay.
MR. LYMAN: Actually, like Bill Magwood
yesterday, I'm not quite sure what's in these
viewgraphs, but unlike him, I did write them myself.
MR. LYMAN: I think it's interesting that
the fuel issue has come up because I definitely had
that on my list as one of the challenges, and I'll go
into that in more detail.
Can I have the next slide, please?
I think the overarching context, I'm the
first member of the public and not the industry or DOE
or NSC to address this workshop. So I am going to
speak generally as a member of the public.
I see the fundamental dilemma of nuclear
power expansion right now is that without massive
subsidy, there are not going to be any nuclear plants
built unless they can really compete with cheaper
fossil fuel sources, and that means perhaps mimicking
these characteristics like low capital costs, short
construction time, modularities of distribution that
we've all heard about, and the question is: are these
really appropriate criteria for nuclear power plants
or is there something fundamental about nuclear
technology which will make that difficult?
Can I have the next slide, please?
DR. POWERS: Well, let me go into just a
question of philosophy a little bit with you here.
Since, I guess, some time in the early '50s, the
government has felt some sense that it should foster
a peaceful use of atomic power, and is there any
reason that that general government feeling should be
viewed as having changed?
MR. LYMAN: Well, in my view there's been
enormous public support of nuclear technology here and
all over the world since the dawn of the Nuclear Age.
I forget what the exact figure is, but it's certainly
in the -- if you include fusion, it's in the hundreds
of billions of dollars at least.
And the question is maybe it's time for
the government to stop weaning nuclear power and let
it go out on its own and see if it can compete.DR.
POWERS: Well, I mean, that's a decision we leave to
the politicians to make. I guess I'm asking have they
made that decision.
MR. LYMAN: Well, if you look at the Bush
policy, you'd have to say no sine it seems to suggest
rekindling a large domestic nuclear research program
and does make reference to technologies which right
now are uneconomic likely processing or accelerated
transmutation, which would require large government
subsidy to actually complete R&D development of this
So if you take that policy on its face,
there may be a change at least in the administration's
thinking. I'm not sure they appreciated that when
they put out the document because I understand they
were stung by some of the criticism by conservative
think tanks of what looked like an endorsement of
government picking winners and losers.
CHAIRMAN KRESS: That's a sign, I think,
of a low battery in there. Have you guys got it?
Pardon me for interrupting you.
DR. POWERS: Okay. I mean, so right now
the inherent assumption in your first bullet is not
necessarily one that has to be made.
MR. LYMAN: Well, I'm saying in the
absence of a policy decision that the public and
taxpayers do not support subsidization of construction
in nuclear power plants, then the rest follows. If
they are, and if that's a decision in the public, then
it's a different ball game.
DR. GARRICK: Would you accept as a
substitute for those three items, low capital cost,
short constructions time, modularity, and ease of
distribution low power costs? I mean, why would you
pick on a component of something that's much more
MR. LYMAN: Well, because these are the
features as distinguished from going to larger and
larger reactors, which is the other way to reduce
power costs through economies of scale.
At least some of the feeling as a member
of the public reading literature, that there is this
feeling in the nuclear industry that by imitating
these characteristics, that is the best way to benefit
from the favorable economics of gas turbines.
There's no more market for large, you
know, very large base load plants, and especially if
you consider the export market to less developed areas
of the world.
You know, this isn't my own conclusion,
but this is what I've heard. If you can come up with
another way of doing it, cutting costs, fine, and we
just heard the gentleman from Westinghouse emphasizing
reduction of capital costs and payback time is so
DR. GARRICK: Yeah. Well, I think the
alternative is power cost because I think that's what
the public wants.
DR. POWERS: Well, I think you've got an
inherent schizophrenia here on the arguments. You've
got arguments that get advanced to us that say, "My
God, there's a crisis. We're going to need tens of
thousands of additional kilowatts," and at the same
time we've got to keep the costs very low.
The two don't match. There's a crisis.
We'll pay what it takes to get the kilowatts.
DR. APOSTOLAKIS: But the subject of the
workshop is regulatory challenges, not national policy
regarding nuclear power. So perhaps we can -- if we
want to finish tonight.
MR. LYMAN: But there is a link actually
because part of the new driver for accelerated
licensing new plant designs is this perceived crisis.
So they're really linked, and one of my concerns as a
member of the public is that there's going to be
momentum toward expediting, streamlining, licensing of
nuclear plants without the kind of deliberation that
I think was probably necessary for the previous
Can I have the next slide?
So the challenge is given these advanced
designs that have the features that I described on the
previous page, how do you maintain issues like without
having a negative impact on safety, on risk of
radiological sabotage on waste management, on
nonproliferation, and on opportunity for public
participation. So these are some of the top level
challenges, and I talk about a few of them.
Next slide, please.
Okay. So the example I'll fix on is a
PBMR, not because I want to pick on it necessarily,
but it is what's coming down the pike, and there's
more detailed information about the approach that
developers want to take.
DR. APOSTOLAKIS: I think you're going to
be more comfortable with this, Lyman.
MR. LYMAN: Right.
DR. APOSTOLAKIS: Where you don't have to
come back and forth.
MR. LYMAN: But I want to see you, too.
DR. APOSTOLAKIS: Oh, okay.
MR. LYMAN: So the PBMR, you know, we've
heard a lot about it. So it's something everyone
understands, but there are fundamental characteristics
which are at odds with conventional balances, defense
in depth elements like the lack of a pressure
containment, significant reduction and safety related
SSCs, a proposed reduction in the emergency planning
zone radius by a factor of 40, and a greatly increased
reliance on fuel integrity to compensate for mitigated
measures to protect public health.
And going back, this is not a new reactor
and neither are any of these issues, and in fact,
neither is the discussion because you go back to the
mid and late '80s, you find the ACRS has already
commented extensively, and I think they wisely stated
in 1988 that it would require unusually persuasive
arguments to justify what they characterized as a
major safety tradeoff.
In other words, emphasis on preventive
rather than mitigative measures.
Next slide, please.
And so with the PBMR, I agree with
Professor Todreas that fuel performance is the big
challenge, and when I started looking at the data
after hearing the pitches made by the PBMR promoters
about how this is meltdown proof fuel, how it's
indestructible, how you have to heat it to 2,200
degrees Celsius to get the fuel to melt, well, it
turns out, of course, that the data that's been
accumulated is a lot spottier than that, a lot less
definitive, and the first interesting thing about the
data for pebble bed fuels, they really don't
understand its performance in relation to changes in
the initial conditions.
And until that understanding is acquired,
it's going to be very hard to implement the kind of
process or product controls that we just heard about
Also, the robustness of this fuel is being
widely oversold right now, and you do not have to get
to the temperature where there's fuel degradation to
have significant fission product diffusion through the
silicone carbide barrier.
And could we have the first, the one with
just one graph on it? Thanks.
Okay. So I started looking at the data,
and this is not the kind of pretty picture we saw
yesterday, and like someone just told me, anyone who
knows anything about pebble bed or gas cold reactor
fuel is aware of this data, but how come we didn't see
it in the last two days?
So I'm going to show it to you. This is
a summary of German data. Sorry it's so out of focus.
This is actual fission product of Cesium 137 release
from TRISO, from actual graphite pebbles with TRISO
fuel in them, and there are a variety of different
burn-ups here, but it gives you the flavor.
This band is 1,600 degrees. This is
release fraction versus heating time, and you can't
really read it, but the upper band is 1,800 degrees,
and you see that you get into quantitative cesium
release on the order of several to ten percent after
50 to 100 hours of heating time at 1,800 degrees.
Can we have the next slide, please? The
And this is substantiated by recent
Japanese data. This is from a journal last year.
Also TRISO fuel irradiating the Japanese gas cooled
reactor, and you see you have the same behavior
roughly after 50, 75 hours of heating time. You get
a rapid increase in fractional release of cesium up
until about ten percent, and this is 1,700 degrees.
That's 1,800. You see you go almost to 100 percent on
silver. You go beyond ten percent at 1,800.
Can we have the next -- actually the
previous computer slide, please, no, the Power Point
Okay. So, you know, here's the gritty
reality about pebble bed fuel, is that the margin to
significant cesium release is not nearly as great as
it is to massive fuel degradation. So I'd like to
hear less about how the fuel is meltdown proof and
more about how the cesium releases are going to be
mitigated in the event of, let's say, a 100 degree
over shoot in the predicated maximum temperature after
Now, so clearly quality control is
paramount since we're being told that the fuel is the
containment in this case, and that raises the issues
about British Nuclear Fuels involvement as one of the
designers of the South African -- of the SCOM pebble
bed fuel manufacturing facility.
And just for a little background, BNFL
almost single handedly killed the Japanese nuclear
industry by exporting mixed oxide fuel to Japan that
had fabricated quality control data, and the reason
why the quality control data was fabricated was
because the people who were working on the production
line got so bored with doing manual checks on this
fuel they decided they're rather just copy sheets of
data, you know, whole bore.
And i think it affects the credibility of
BNFL, as well as raises general issues about how
reliable, how much emphasis you can put on fuel
reliability and quality control in affirming reactor
safety, and that's why I would throw out that the
fabrication plant really is part of the reactor system
and, therefore, there's going to have to be greater
involvement in fuel fabrication by NRC even if it's
done overseas, I think, than is customarily the case,
according to Appendix B criteria.
And so I'd suggest that there has to be an
ITAAC on quality assurance for fuel manufacture in
this case, a programmatic ITAAC.
Next slide, please.
MR. SIEBER: Maybe I could interrupt. The
first graph that you put up, could you tell me where
it came from?
MR. LYMAN: Yeah.
MR. SIEBER: I want to read the whole
MR. LYMAN: From the reference that's in
IEA Tech. Doc. on fuel, pebble bed or gas cooled
reactor performance, and I don't think I have the
number with me, but I'll get it to you afterwards.
It's within the last three years or so.
MR. SIEBER: Okay.
MR. LYMAN: It may be 978, but I'll have
Okay. So --
DR. POWERS: I think I can find it for
MR. SIEBER: Thank you.
MR. LYMAN: Now, on the issue of safety
goals, which we've heard something about, I think that
the safety goals do need to be reexamined for
advanced reactors, and I don't think the current goals
are conservative enough.
And a little thought experiment is that if
you actually remove the containments from most light
water reactors operating today, would they still meet
the safety goals? I think at least according to the
existing calculations, they would, and that's because
anyone in the industry will tell you they were already
a factor of ten or more below the safety goals in
And since containment performance is
predicated on a ten percent -- less than ten percent
conditional containment filler probability, I think
this is an example of why the existing safety goals
should not be the target for advanced plants.
We also need to define --
DR. APOSTOLAKIS: Excuse me. I think this
is going to be challenged a little bit. You are
evaluating the usefulness of the goals by going
through the plant and say, "Well, gee, the plant is
really much better than the goal. Therefore, the goal
is not conservative enough."
I can pick the other line and say, "Well,
gee, the goal will be set independently of the plant
by using some societal measure. So one tenth of one
percent of other risks, I don't know that that's not
MR. LYMAN: I agree, but I'm not sure
that's the history of the development of those goals.
I mean, it is kind of convenient that they were chosen
at a level where the fleet of plants does meet them
with a large margin. Maybe it's just a suspicion, but
you know, that number was picked out of a hat as far
as I can tell.
Okay, but fair enough.
DR. WALLIS: But you could remove the
statement "not conservative enough." It might still
be valid to say that the goals could be met with
containments removed, if that's a true statement.
That's an interesting statement to make.
MR. LYMAN: Well, if that is true, it
makes one think. I'm not, of course, recommending
DR. APOSTOLAKIS: That was my next
MR. LYMAN: No, I'm not recommending it.
I'm just wondering if the existing safety goals do
capture what needs to be captured in the public
concept of reactor safety.
And in the industry in the West, it really
dug its own hole in this regard. After Chernobyl, the
chief response from the Western nuclear industry is
that can't happen here because our plants have
So you have to think a little bit about
how the public response is going to be when you try to
introduce graphite moderated reactors in the
containments in this country.
One issue is what do you do with the
concept of a large early release, especially if you
have a reduced evacuation zone. I think you need to
think in terms of a large release in the case of the
pebble bed. Since there's going to be a large number
of people who no longer have instructions to evacuate,
and given the type of cesium releases that I think the
fuel is capable of, this is something that also I'd
like to think about.
CHAIRMAN KRESS: If you're not going to
have evaluation, the E ought to go out of the ERF.
MR. LYMAN: Right. There's no meaning to
CHAIRMAN KRESS: Yeah.
MR. LYMAN: And since a lot of these
released don't occur until 50 hours into the accident,
then, you know, that also has to be figured into it.
And so one issue, you know, is is it going
to be necessary to add additional requirements to the
pebble bed to make it safe enough, and the IEA pointed
out or it was actually an IEA document where I saw the
statement that if a whole lot of additional
requirements had to be imposed, it would really
threaten its economic viability.
Yet there are some characteristics we're
thinking about. One is the fact that there is no
secondary coolant loop in the SCOM design. Yet the
MIT design proposed by Kadak does have one for the
reason that it reduces the risk of water ingress.
So the SCOM design isn't the last word in
the pebble bed, and there has been discussion
apparently in the literature about coatings which are
better or more refractory in silicon carbide than
zirconium carbide, and maybe the whole issue of
whether the fuel, the traditional TRISO fuel is
These all have to be opened up, and I
don't think in the schedule that's been laid out
there's going to be enough time to do that.
Next slide, please.
My next major concern is the issue of
radiological sabotage, which I think could be a show
stopper for certain features of advanced plants that
have been suggested.
Just to beat a dead horse, 50 percent of
U.S. nuclear plants today have failed their OSRE
exercises, meaning that mock terrorists can simulate
enough damage to cause the core in a force/unforce
Exelon's Quad Cities was an example of a
failure in early 2000. To quote from the inspection
report, deficiencies in the licensee's protective
strategy enabled the mock adversaries to challenge the
ability to maintain core cooling containment.
So I'd like to see Exelon concentrate a
little more on defending their existing fleet of
plants before starting to site new ones.
Next slide, please.
And the basic point here is that no matter
how inherently safe a plant is from accidents, there's
always going to be a scenario, I believe, that someone
clever enough can cause fuel damage, and this was
touched on actually in this morning's discussion.
And that means to me that you're not going
to be able to justify drastic reductions in the
security force requirements for pebble beds, and also
that the issue of additional defense in depth measures
like containment may be warranted for that reason even
if probabilistically they're not warranted from an
And, third, plants that have in situ
reprocessing modules like the PRISM we heard about are
going to be unusually attractive because you already
have fuel that's in process in a disbursable form.
It turns out that the very wise ACRS in
1988 recommended that sabotage resistance be a design
feature, general design requirement for advanced
plants, and I don't think I see that in the current
generation that's been proposed. In needs to be
thought about, and there needs to be involvement now
with the NRC safeguard staff in trying to challenge
the pebble bed from the point of view of sabotage.
Next slide, please.
Waste disposal is the third challenge.
Obviously the issue of waste disposal is going to be
a driver in whether we can sustain an expansion
nuclear power in this country, and the other issue
that the pebble bed people don't like to talk about is
their waste. And rather than minimize waste as was
one of the Generation IV requirements, the pebble bed
generates a volume of waste, ten times as much,
something I verified myself by calculation, meaning
that storage and transport requirements per kilowatt
hour generated are going to be ten times greater, and
you'll need ten times as many packages in a repository
if you ever get to that point.
Thinking about the problems that are
already going to be encountered in transport, it seems
that ten times as many shipments from the same amount
of electricity might raise a red flag.
The other issue is Carbon 14, specially in
the context of the repository. You're going to get
quite a lot more Carbon 14 in a gas cooled reactor
design, and because of gaseous emissions, the gaseous
emission issue in an unsaturated repository, that
could be a dose problem.
Next slide, please.
So just from a public acceptance
standpoint, getting back to my original point, I think
that a better approach for new plants, if the industry
really wants public acceptance, is not to try to cut
margin where it can, even if it claims it has a safer
The goal should be to increase safety, the
next step, and that would in my mind suggest a limited
number of sites that are well protected rather than
small scale reactors which are widely disbursed, and
might require gold plating instead of trying to shave
margin where you can find it, and that approach would
be inconsistent with these performance based
tendencies that we've heard about earlier today.
Next slide, please.
And the aggressive licensing schedules
that have been proposed, I think, are also going to
aggravate and generate public opposition, and it's
really better to proceed cautiously to make sure
there's full resolution instead of trying to expedite
That's all. Thanks.
CHAIRMAN KRESS: Questions or comments?
MR. SIEBER: Do we have copies of these
DR. POWERS: Did you want to say anything
about resistance in connection with the PBMR?
MR. LYMAN: Well, there are two issues.
One is the fact that it's on line fuel, which I think
will increase the safeguards' inspection requirements.
Of course, it's not an issue in the U.S. since we
don't -- you know, we have voluntary safeguards at
nuclear plants, but overseas it could be a problem.
It's going to take more work to inspect,
you know, system discharges. What is it? Tens of
thousands of balls a year, I think, or more as opposed
to a system where you only have to be present, an
inspector only has to be present once every year and
a half or two years to observe core loading.
Now, the tradeoff is that the fuel is
quite dilute. It would take a lot of it, as we heard
this morning, to divert a significant quantity of
But, on the other hand, if you have a
large utility that operates a large number of these
plants, if let's say there were some malevolent desire
on the part of the operating company to divert small
numbers of fuel from each one of these modules, then
you could have protracted diversion as an issue.
So the safeguards requirements are really
going to require some evaluation.
DR. GARRICK: There is one part of your
message that I like very much, and I think the NRC is
quite sensitive to it, and that is that the industry
has to be very cautious about overselling the PBMR,
for example. That kind of activity has been a result
in the past and has been an example of the industry
shooting itself in the foot.
And I would agree that there seems to be
a wave of confidence and enthusiasm towards the
concept that from a scientific and technical
standpoint certainly has not been demonstrated on any
kind of systematic, evidentiary basis at least yet.
So I think that's a good comment.
DR. TODREAS: Can I make just two comments
on things that you mentioned?
I was not here yesterday and, therefore,
don't know exactly what you've heard, but my
understanding on two points is the following.
On the secondary system difference, my
understanding is that Kadak has gone to the secondary
system because of development times and requirements
on the helium power cycle. He has not gone there
because of a feeling that water ingress is a problem
that can't be beat on a direct cycle.
So I would suggest you discuss that
further with him on that.
And, second, on the depressurization
transient and the temperature that the fuel is allowed
to go to, I thought 1,800 or even less was the maximum
limit that it had always been designed to.
I got the implication from what you put up
that the target was up at 2,000 or so.
MR. LYMAN: No. I mean, I don't know what
the target actually is, what the number that's used,
you know. When Exelon or whoever is presenting this
data to the public, they use the figure 2,000. It
appears in a whole lot of literature, and so that
gives the impression that there's a bigger margin than
there may actually be to fission product release.
That's my only point.
DR. TODREAS: If the number 2000 is being
used, but the design calculations and the criteria
from analysis on the depressurization, at least in the
context I'm familiar with, has always been lower than
that. Eighteen hundred may be a little bit lower, but
since I don't remember exactly, I don't want to say
MR. HOCKRITTER: I was going to say I
think it's around 1,600 C.
DR. TODREAS: Yeah, okay. I've got 1,600
to 1,800. I wasn't sure of the exact number.
MR. SIEBER: He said 1,600.
DR. TODREAS: But the point is that number
encompasses some awareness of -- I think a great deal
of awareness -- of the data that you show. So I think
you might take some comfort and actually talk to the
analysts about that.
MR. LYMAN: But, you know, one needs to
see what the uncertainty is in these calculations and
what the actual error bars are and the maximum
temperature. What are the factors that could
conceivably cause the final temperature to be
You know, that's the kind of systematic
thing that hasn't been presented to the public yet,
and my concern is, you know, the numerous articles,
and there's an enormous amount of press interest in
this reactor, but the claim is it's meltdown proof no
matter what happens to it. You can't get
radioactivity out of it, so you don't need a
containment, et cetera.
And I think that kind of talk is
DR. WALLIS: I think there ought to be
more reassuring. If Exelon had presented the kind of
curves that you presented and the worst curve which
they presented was one which was not on a log scale;
so everything sort of disappeared down to the
reactors, then appeared to come up at 2,000.
That doesn't tell you anything about this
kind of stuff that you presented.
MR. LYMAN: Right.
DR. WALLIS: So it may well be that the
scheme is all right. It's just that it will be more
convincing to the technical community. They presented
this stuff, and we didn't have to hear it from you,
and I think that's a good point.
CHAIRMAN KRESS: All right. Why don't we
move on to the next speaker, which according to my
list is you, Ron Simard. You're welcome to make any
sort of presentation that you wish.
MR. SIMARD: No slides. Just a comment.
My focus would be on the near term
challenges facing NRC, and I go back to my
presentation of this morning, but I would very
strongly endorse what Rich Barrett said.
I think we need to keep in mind this fact
that the credibility of the regulator and the process
is essential to the industry to be able to meet our
objectives. So I would roger everything that Rich
said -- Roger Rich -- I would roger, Rich, everything
that you said.
With respect to the need for a tangible
and clear demonstration of safety, involvement of the
public, I would certainly pick up on your suggestion
that we do need this early resolution of some of the
open issues because as I said this morning, the
potential licensees of the future are looking for much
more certainty and knowledge of the licensing costs
and schedules than they've had in the past.
And certainly I would roger his points on
efficiency. With respect to the work force, one of
the things that we're doing in terms of trying to
assure that we have the work force we need for the
future is we're working with this group of young
professionals now called Young Generation North
America, and the definition of young in this case is
35 years old.
And as Rich was talking about the
importance of the work force to the NRC, I looked
around the room at some of the NRC staff in the room,
and I wouldn't ask for a show of hands, but look
around and you guess how many of the NRC staff in this
room would be eligible to join the Young Generation.
So I would certainly agree that there is
a challenge to the NRC in terms of maintaining not
only the number of people, but the level of skills.
I think Dr. Garrick mentioned the level of skills and
so forth, but I think one of the points I see us keep
returning to in the last couple of days is the
importance of this risk informed approach to meeting
some of these objectives that we've been talking
about, for example, being able to demonstrate to the
public what is significant in terms of safety and
being able to assure the NRC, the licensees and the
public that we are, in fact, focusing our attention on
what is significant.
We've heard a lot of discussion about the
need to draw even more on some of the successes we've
had so far in implementing this risk informed approach
and being able to take advantage of the new insights
But I would suggest that maybe one of the
biggest challenges of all is the culture change that
the NRC is going to have to implement to be able to
get acceptance of that across the agency at the levels
that are going to be needed to handle the licensing
challenges in the near future.
And that comes from the top. That
CHAIRMAN KRESS: Why don't we move on to
Ms. Hauter? You're the anchor today.
MS. HAUTER: Well, I always enjoy coming
to the NRC to meetings because I never have to wait in
the ladies room.
MS. HAUTER: And I hope that I'm not going
to add to any gender stereotyping, but I don't have a
Power Point presentation, and I didn't get the
questions beforehand. I've based my comments on what
I've heard at this meeting.
And I don't think that I would have used
a Power Point presentation anyway because I think it's
my role as coming from public citizen to speak plainly
as a member of the public.
So even if you don't like what I have to
say, I promise there will be no techno. talk, no
incomprehensible jargon, and no indecipherable
PARTICIPANT: Thank you.
MS. HAUTER: We've heard a very rosy
picture painted this morning. I think that it was Ron
who talked about the poll in California, that public
now supports nuclear power, and I'd like to say that
we've done a lot of polling, been involved in a lot of
polling through the years, and that the public always
supports renewable energy and energy efficiency first,
and that that is a very deep support.
And in fact, the Post had an article today
showing that President Bush is losing support, and
that 58 percent of the American public now disapprove
of his energy plan.
So I think that when the numbers of
nuclear power plants go in two days from 200 to 1,000,
that that's your biggest challenge, is when you're
talking about these large numbers, and you have almost
no public participation in a meeting like this, that
our telephone is beginning to ring off the hook, and
you're helping us mobilize a new anti-nuclear
So, you know, I would consider that in
these kind of large promises that are being made.
Now, I think that we all know that through
the years, that the cooperation of the industry and
the agency has led to a weakening of the democratic
process both of licensing and siting new plants, and
I suspect that people in the room feel that that will
certainly help this new generation of plants, but I
think the biggest challenge is going to be about some
of the issues that Ed spoke of, especially the issues
As I sat here throughout this meeting, I
heard a lot of words that really mean taxpayer money.
Let's see. We heard cost sharing, government R&D,
talk about the Price-Anderson Act or even the license
by test with the government picking up the cost for
the test facility and the liability.
And you have to have political support to
get that kind of level of subsidies, especially for
the number of years that you're talking about, and I
think that it's a real problem when at the same time
we hear an analysis of the electric industry in 24
states have deregulated and we hear that we've now
moved into this deregulated, competitive marketplace,
and we could argue about whether that is true or not,
and I would say that it's not true, but that is
certainly what the public is hearing.
And we also know that the reason that
nuclear power is so cheap now in these deregulated
markets is that O&M is cheap because of the huge bail-
out that's occurred at the nuclear industry, over $200
million for all of the stranded costs, and so
basically the mortgage has been taken care of, and
that's why the issue of capital cost is so very, very
But this puts you in a very vulnerable
position because, on the one hand, people are talking
about this competitive market, and on the other hand,
this plan that you've laid out is going to take
massive subsidies, and we're going to see a fight over
the reauthorization of Price-Anderson.
Now, I recently had a very interesting
speaking engagement, and I probably won't be asked
back to speak at this for a number of these gatherings
either. It was the Institute for Infrastructure
Finance, and I'd never heard of this organization. I
had to look it up on the Internet.
It's a group of, an association of the
financial institutions that build power plants and
water projects and so forth. And I sat through two
days of this meeting. In the last session I debated
somebody from Cato about energy policy.
The whole tone of the meeting was getting
the public to accept paying higher power costs, but
these investors expect to get a 35 percent rate of
return on profit after just a couple of years of
investment. They're going to get in and get out
quickly. I mean it was enormous profits that they
were talking about.
And I asked a number of the bankers and
investment institution representatives there in
conversations and publicly whether they were going to
invest in nuclear power, and not one person said that
they were. In fact, I was laughed at.
So I think that there are some major
challenges around subsidies and costs.
The third point that I'd like to make is
that the theme of this meeting has been how to further
deregulate the regulatory authority of the NRC, and
I'll have to tell you I am always appalled when I hear
things like the regulatory process described as a
negotiation because negotiations take place between
partners of equal power and ability, and in my mind,
regulation, especially what the NRC is supposed to do,
is a government function with the goal of protecting
the public's health and safety, not protecting the
profits of the nuclear industry or the future of the
So the idea that the mission -- and I know
that this negotiation talk has been going on for some
time -- but it just to me demonstrates the abysmal
state of regulation, and unfortunately, I think the
truth is closer to has become a negotiation process,
and that's because of our political situation and our
system that we believe is a system of legalized
bribery, where public policy is led by campaign
contributions and lobbying.
And we believe that the Nuclear Energy
Institute and their ability to give campaign
contributions and to influence Congress has grown
Now, whether this will continue and we'll
be able to get the amount of subsidization that is
required, we don't know, but I think that all of this
conversation that's taken place here has taken place
without any political context, and that that's another
thing that's very disturbing to me, is that there are
a number of other things going on politically besides
this new generation of plants, and I'd like to just
mention a couple of them because I think they all play
into the health and safety concerns that we have.
One thing is IAEA's attempt to harmonize
radiation standards across the world and to increase
the amount of radiation that the public can be exposed
The other is the National Academy of
Sciences' BEER 7 (phonetic) Committee, which we
believe the deck has been stacked with scientists who
support exposing the public to higher levels of
There are the DOE studies that are going
on, the radiation studies, which we don't believe will
be done fairly.
And then there's the NRC's process to
deregulate a category of low level nuclear waste.
So the thrust of all of this is that the
public can and should be exposed to more radiation,
and then when I come to a meeting about a new
generation of plants, and I hear almost no real
discussion of how many radiation releases, what the
amount of the radiation releases are, and it's all
really shrouded in technical talk and not real talk
that people can understand, I think that that's a real
My next point is related to the political
context, and that's the discussion of regulation, and
I think most of the presentations here talking about
licensing and so forth used code words for
deregulation, and we're concerned about the
deregulation of safety records. I'm concerned when I
hear jokes being made and the ACRS Committee
suggesting that NEI isn't going far enough in
rewriting regulations, even though I believe that was
tongue in cheek.
And I think that we've heard a lot of code
words that really mean deregulation and letting the
industry regulate itself, and those code words are
risk informed, probabilistic risk assessment, common
regulatory framework, cost-benefit analysis, new
You know, the theme of this meeting is how
can the industry work with the NRC to rewrite safety
regulations so that this new plant, new generation of
plants can come on line, appear to be safe, get public
support, and be economic. And we're not supportive of
those kinds of deregulatory efforts.
I'm always very concerned when I hear
about merchant plants as well, because we've seen what
has happened, what is happening with merchant plants,
for instance, the natural gas plants.
I live in rural Virginia. We're now about
to get our third natural gas merchant plant, which is
coming in under the Clean Air Act because of a
We know that there are thousands and
thousands of megawatts of merchant plants planned, and
there are a lot of questions about the experience of
the operators and their financial viability, and I
think that it will be of grave concern to the public
that there will be merchant nuclear plants.
And I guess lastly, I'll just briefly
mention the democratic process because I am a great
believer in democracy, and I don't see the process
that's been described as having any room for public
participation because I don't really believe that the
industry thinks that the public supports nuclear
power, even if we quote polls.
And so, you know, it's damaging to our
democracy when we take away the public's right to
engage in discussions about siting and licensing, and
we need to have as much public participation as
CHAIRMAN KRESS: Do you have a suggestion
on how that could be done?
MS. HAUTER: Well, I think that these
meetings, a meeting like this, if it's held on a work
day and the content is incomprehensible to most of the
public, that the public is not -- you know, you have
to go out of your way to get the public to
participate, and I think there should be hearings
around the country, and that there should be much more
of an outreach effort to engage the public.
Because just referring to Mr. Power's
comment about, well, it's the government's policy to
support nuclear power, our government is made up of --
you know, it's a democratic government, and it's what
the people support, and so, you know, the people
should be involved in making these decisions as much
And I see people shaking their heads. So
I think that's the fundamental problem.
DR. POWERS: Just to correct you, it's a
MS. HAUTER: Yeah.
DR. POWERS: I mean it's a federal. It's
not a democratic republic.
CHAIRMAN KRESS: Questions, comments?
DR. WALLIS: Well, we have, I think,
several times in this Committee mentioned that public
meetings should involve the public, and we are
concerned that they tend to involve people who have
some particular interest, which is not perhaps
representative of the public, and we've struggled with
how to do that.
Whether, in fact, the NRC should somehow
-- how do you get public input? How do you get sort
of informed technical people who are not part of the
nuclear empire, whatever you want to call it, to go
there and actually give their attention to it?
I don't know, but we have talked it a fair
amount, I think.
CHAIRMAN KRESS: In fact, I think the ACRS
considers itself as a public -- taking care of public
interests in this whole institution actually. That's
the way we view ourselves. So we want to do it in a
responsible, technically defensible way.
And you know, if this is a technical
issue, it's not always possible to resolve it without
using technical jargon or technical arguments. I
mean, it is a technical issue.
MS. HAUTER: Yeah, and can I just answer
that? I don't think that it's not a technical issue.
I think if you want public participation, you hold
meetings where the public can come to them.
I mean, you know, you hold meetings during
the time that the public is available. Most people
aren't going to take off from work, and probably they
can't come, you know, to a two-day meeting, not that
you shouldn't have two-day meetings, but you could
plan special meetings in different locations that the
public could get to.
DR. POWERS: I think in fairness it's
important to understand that this particular Committee
meeting was done to educate us. I mean, it wasn't
really intended to be a public, though we invite the
public to participate, and sometimes we actually get
some participation. But this was for educating us.
DR. WALLIS: This meeting is actually
being recorded, too. So the transcript is available
on the Internet. Anybody who wants to who has the
access to the Internet.
CHAIRMAN KRESS: Well, I think --
DR. TODREAS: Could I ask --
CHAIRMAN KRESS: Yes, you may ask.
DR. TODREAS: -- a question?
I wanted to just drag out a little bit
more on this. This terminology being used here, "risk
based," my whole image of this is that's an approach
to try to get everybody to focus on the biggest
issues, the biggest regulatory issues associated with
plants, the biggest potential hazards associated with
So my whole perception was that that was
a move in the right direction relative to putting
people's attention on the key things, and what I
gather from your reaction is that whole thrust not
only misses you, but actually raises suspicions.
So what is the right -- well, first, I
mean, do you have any sense as to why or the positive
effect that's trying to be accomplished by this
thrust, and do you have better words or is there a
better way we should project this?
MS. HAUTER: Well, I think risk based
analysis had its roots in the late '70s and especially
then after the Reagan administration, and it was part
of the deregulatory effort. It was to make regulation
cheaper and less costly for industry. So I'm going on
the roots of where risk based analysis comes from.
So it's not the words that I'm objecting
to. It's the idea that agencies are not going to
regulate, but that we're going to set up this regime
where you're looking at, you know, what is supposed to
be the largest risks.
And I think that what it ends up doing is
making it appear as if there are fewer risks and, you
know, that it's been basically a way to deregulate and
make the regulatory regime cheaper.
DR. TODREAS: Yeah, past political
MR. BARRETT: Can I address that? I'd
like to say a word about that.
I think that the experience of the NRC
with regard to risk based or risk informed regulation
may not be the same as what you've experienced in
other regulatory agencies. We got into risk informed
regulation or risk based regulation in that time
frame, in the late '70s, throughout the '80s, and up
And I would say that in the '80s,
following the Three Mile Island accident, for
instance, it would be possible to list a number of
very, very important new requirements that were placed
on the regulated industry as a result of our risk
And so I don't know that for this
particular agency it's fair to say that risk informed
or risk based regulation has been a deregulatory
trend, and I would have to second what Neil said. I
think that when we see the proposals from the industry
to take a risk informed look at our regulations for
these new types of reactors, we know that there are
some of our regulations that are specific to water
reactors, and really it would be just wasteful of
resources to try to apply them to these new types of
And we also know that there are challenges
to these new types of reactors, such as the fuel,
which we've never faced before for a reactor, trying
to think of the fuel as part of the licensing process
that we're going to have to address.
And so we feel that we need a systematic
and technical way that we can lay all of these issues
out on a level playing field and say which ones are
important and which ones are less important, which
ones do we concentrate our resources on.
So our general tendency is to welcome a
risk informed approach and to go forward to use that
risk informed approach to come up with an optimum
MR. SIEBER: Maybe I could add to that a
little bit. My impression, having once worked in the
industry, was that risk based approaches cost us
money. One thing that was identified through the
reactor safety study was event fee, which intersystem
LOCAs. We had to change our plant for that. IPEs
generated design changes for us, and that improved
And I think that risk based approaches go
in two directions. You may find when you apply this
technique to a plant that you have to modify the
plant, modify the way you operate the plant to make
the plant as safe as you can.
And, on the other hand, there are things
that are in the regulations that are in the plant that
when you study them have no risk basis at all and
probably represent a cost burden to the licensee for
no safety gain.
So I think it goes both ways, and that's
the way I perceive what has gone on in applying risk
based techniques in the industry over the last 50
years or so.
DR. WALLIS: I see risk based regulation
as being or risk informed as being a way of being
honest with the public. I mean, the whole idea of
regulation is to hold the public risk to some
acceptable level, which is acceptable to the public,
not something that's acceptable with an agency.
And that communication has to be there on
the basis of what risks are you exposed to and what
risks will you tolerate.
So it has to be in the language of risk,
and it has to be measured in some way. It can't be
vague and waffley. So it seems to me that measures of
risk and explaining how we make those measures of risk
and how we interpret them and how we decide presumably
by some political process about what risk is
acceptable is the honest way to do business rather
than talking about a lot of technology and loss of
coolant accidents and design based accidents and all
of these kinds of things, which are technical things.
The common language really ought to be
language of risk. So I don't quite see why there's a
problem with doing it that way.
MR. LYMAN: Can I just share my
I think the concern the public has is that
industry is only interested in risk informed
regulation when it perceives that the existing
regulations are too conservative, and then making the
changes would only go in one direction.
And one good example is the attempt to
risk inform the 50.46, which is the combustible gas
control regulations is something industry sought
because they wanted to get rid of a whole lot of
systems like hydrogen recombiners and hydrogen
monitoring that they didn't want.
But when it turned out that there may have
been a couple of aspects, for instance, having a back-
up power supply for hydrogen igniters in the case of
the station blackout in ice condenser plants, that
would have introduced -- that was a risk measure that
would, by the same token, have to lead to increased
requirements, and so then the proposal from NEI was we
want selected implementation, which is we can choose
whichever we want and forget about the others.
So that gives the impression that they are
really only interested in those that reduce cost and
If it's applied systematically, then I
agree with you. But then the issue is brought up of
how accurate are the risk assessments to begin with.
CHAIRMAN KRESS: That's why NRC's job is
difficult. They're there to make those judgments, I
think, and to help make them, and I, for one, think
they are very diligent about that sort of thing.
DR. WALLIS: Well, part of the problem may
be that NRC is perhaps set up, and maybe it has to be
by law, to respond to industry, and if industry does
only ask the things which appear to benefit them, then
that may be not a very good system. Maybe that's the
way -- I'm a bit concerned about that, that the NRC is
responding to things.
Well, maybe it has to respond to other
forces or maybe your influence, too. That's another
CHAIRMAN KRESS: It does have to respond
to petitions. That should be the other route.
MR. SIEBER: Well, it's responding now
with the development of performance indicators. It's
responding to industry trends and plant trends. It
responds to its own inspection program. So that
actually goes both ways, too.
DR. APOSTOLAKIS: What's wrong with the
industry being interested in cutting costs, Mr. Lyman?
It's the job of the agency to make sure that they
don't do anything that creates undue public health
risk, but the fact that industry is interested in
reducing the operating cost, I mean, that's not a
I mean everybody has an agenda.
MR. LYMAN: Sure.
DR. APOSTOLAKIS: It's the agency's job to
make sure, you know, that the requests that are
granted are really legitimate, and they don't really
And the other thing is I'm always, you
know, amazed, not amazed, but maybe puzzled that we
always talk about public interest groups, public
interest groups. What's wrong with considering the
Nuclear Regulatory Commission as the number one public
interest group when it comes to nuclear affairs?
Now, you have five Commissioners that have
been appointed by the Senate, I mean the President
with the approval of the Senate. You know, every
year, you know, we have a new one, and they represent
Then you have the staff, professional
people. Aren't they the number one protectors?
I don't hear anybody giving them enough
credit. So we have to go out and have evening
sessions to meet with the public? The public will get
very bored when we get into technical matters, and
this Committee is supposed to advise the Commission on
technical matters. Why? Because the Commission is a
group of political appointees. They're not expected
to have the technical expertise that's required. They
represent the people.
Don't they represent the people? I'm
MS. HAUTER: The problem is in our
political system, the industry is able to influence
Congress, the appropriations process, the executive
branch of government through campaign contributions,
through lobbying, through a revolving door, and so
that type of influence -- the NRC has to be responsive
to industry in a way that we believe is not always
representing the public interest.
And in a democracy you have tensions
between different constituencies, and that's what I
think we're discussing here.
MR. SIEBER: But if public opinion is as
you say, and I've heard the same stories you did on
the recent California polls, the politicians, I think,
would respond on the side of where the votes are going
to come from, hopefully, and that should be a check
and balance on the whole system, which is what I think
MR. BARRETT: I'd like to change the
subject a little bit because I want to get to this
question about public participation. That's an item
that's always challenged this agency, and over the
past four or five years we've made a concerted effort
to try to improve our performance in that area.
We have tried to have meetings that do
make it easier for people to participate at least in
terms of trying to knock down the amount of technical
jargon, trying to have facilitators who can make sure
that everybody is up to speed on what's going on.
But it's still an area that's a challenge
for us, and I can tell you we're going to have this
workshop in July. It's two days, and it's during the
work week, but we will try very hard to make sure that
it's a discussion that's open to everyone because at
that session we are going to be talking more about how
we make decisions and this whole question of risk
But I think the issue of how we get out
and make the process even more accessible is something
that I think we need to think more about.
CHAIRMAN KRESS: Well, with that note, I
think I'm about ready to declare this Subcommittee
meeting over with, unless someone has some burning
DR. APOSTOLAKIS: Did you give the public
an opportunity to --
CHAIRMAN KRESS: Well, I'll tell you what.
I would -- you know, I don't want to put anybody on
the spot, but we do have ex-Commissioner Rogers here,
and I would love to hear any words he would like to
give us, any words of wisdom and thoughts on the whole
MR. ROGERS: Well, thank you very much.
There's a lot of things I could say, but
I think one of the things that I really would like to
say in response to this criticism of risk as a basis
for anything, that I've been very enthusiastic about
the use of risk analysis by everybody, and the reason
is that it is a systematic way of looking at the whole
system, not piece by piece, isolated pieces, but at
the whole system.
And that's one of the biggest problems in
any large, complex, technical operation, which
normally gets broken down into individual management
pieces -- manageable pieces that can be dealt with,
and then they're all assembled, and people say, "Now
it's all done. It's fine."
And yet you know that when you put them
together, you've got a system that has new features,
new ways of expressing itself that you hadn't seen
before, and that risk analysis, probabilistic risk
analysis is a disciplined approach, a technically
disciplined approach to looking at the interactions of
all the different parts of a complex system, how they
influence the behavior of the whole thing, and each
And what the bottom line number is that
comes out of that may not even be that important, but
the process of looking at the entire system of how the
parts interact with each other and using probabilistic
analysis to quantify this process and begin to allow
you to pinpoint where the really serious aspects of
the system are from a safety point of view is an
enormous advance in the protection of public health
It is not a dodge. It is not a subterfuge
to avoid doing the right thing. It is a powerful
technical analysis that has not yet come totally to
maturity. There are things that we don't know how to
include in it. We really don't know how to include
human performance in it very well, and we know when al
is said and done, many times that is the controlling
But nevertheless, I think it is really a
shame to consider risk analysis as simply some kind of
a political tool. It is a technically sound
discipline that is maturing. It is not totally
mature, but it is maturing and has already revealed
many, many important issues in nuclear power plants
that were somewhat I won't say undiscovered, but not
thought to be very important.
So that, in fact, it does cut both ways,
that there are aspects of what we have put in place as
regulations that were done early on in the history of
the business because we didn't know any better. So we
thought, well, that's at least some way of dealing
with this problem.
And as time has gone on and we've been
able to learn more and more about the total system and
risk analysis, the discipline of risk analysis has
been brought to bear on the safety of a total nuclear
plant. Enormous strides have been made in
understanding their behavior.
And I think that the much improved
performance of nuclear power plants not only in the
United States, but throughout the world is, in part,
a result of the application of risk analysis to being
able to pinpoint where the weaknesses are and correct
So I really hope that you could take away
from this meeting at least a sense that this is a
technical tool that, in fact, has great power and can
produce and has produced significant improvements in
plant safety not only here, but throughout the world.
CHAIRMAN KRESS: George, you may have the
DR. APOSTOLAKIS: This reminds me of a
debate we had last week as the symposium that John
Garrick hosted under the auspices of the Society for
Risk Analysis, and I objected then, and I will object
It seems to me that it is a
miscommunication to talk about risk analysis in
general because I understand your complaint about the
'80s, risk analysis being used as a political tool,
which to a large extent it was.
Risk analysis as used by this agency is
not the same risk analysis as used by EPA or chemical
oriented kinds of analysis. We're dealing here with
a very complex system.
I think the other federal agency that
comes close is NASA with the international space
station, and so on, very complex, technical systems,
and I really think it's miscommunication to call what
we do risk analysis and then call what the EPA does
That's why we're using PSA, probabilistic
safety assessment. I think what the Commissioner
referred to is this systematic approach to a very
complex, technical system that really brings out the
weaknesses and so on.
And I think in the chemical world the use
of risk analysis is different, although the
philosophical approach might be the same. The actual
tools for implementing it are different, and a lot of
the criticism regarding risk analysis from public
interest groups really has in mind the EPA, and
generalizing, I think, is not, in my view, appropriate
because there are a lot of technical benefits from the
probabilistic safety assessment we're doing here.
Unfortunately we have to use jargon and so
on, but anyway, I really think risk analysis is too
broad a term. It doesn't really cover what we are
CHAIRMAN KRESS: Wonderful. Well, I would
like to thank all of the participants in this two-day
meeting. I'd like to especially thank this panel who
I think have done a very good job.
And with that, I'm going to declare this
(Whereupon, at 5:49 p.m., the meeting in
the above-entitled matter was concluded.)
Page Last Reviewed/Updated Tuesday, August 16, 2016