Protecting People and the EnvironmentUNITED STATES NUCLEAR REGULATORY COMMISSION
UNITED STATES OF AMERICA
NUCLEAR REGULATORY COMMISSION
***
MEETING: 106TH ADVISORY COMMITTEE ON
NUCLEAR WASTE (ACNW)
***
U.S. Nuclear Regulatory Commission
Two White Flint North
Room T-2B3
11545 Rockville Pike
Rockville, Maryland
Wednesday, February 24, 1999
The committee met, pursuant to notice, at 8:32 a.m.
MEMBERS PRESENT:
JOHN GARRICK, Chairman, ACNW
GEORGE HORNBERGER, Member, ACNW
CHARLES FAIRHURST, Member, ACNW
RAY WYMER, Member, ACNW
MARY L. THOMAS, Member, ACNW. PARTICIPANTS:
PRESENT FOR THE ACNW STAFF:
DR. LARKINS
ANDREW CAMPBELL
LYNN DEERING
RICHARD K. MAJOR
ACNW CONSULTANT:
MARTIN STEINDLER
PRESENTERS:
ERNEST L. HARDIN, Technical Lead, Near-Field
Models, DOE Office of Civilian Radioactive
Waste Management
CAROL L. HANLON, Yucca Mtn. Site Characterization
Office, DOE Office of Civilian Radioactive
Waste Management
DAVID STAHL, Waste Package Materials Dept., CRWMS/
M&O Natural Environmental Program Operations,
DOE Office of Civilian Radioactive Waste
Management
DWIGHT T. HOXIE, Process Models and Performance
Assessment Support, CRWMS/M&O Natural
Environment Program Operations, DOE Office
of Civilian Radioactive Waste Management
PARTICIPANTS: [Continued]
PRESENTERS: [Continued]
STEPHAN BROCOUM, Office of Licensing and
Regulatory Compliance, Yucca Mtn. Site
Characterization Office, DOE Office of
Civilian Radioactive Waste Management. P R O C E E D I N G S
[8:32 a.m.]
DR. GARRICK: Good morning. The meeting will now come to
order.
This is the second day of the 106th meeting of the Advisory
Committee on Nuclear Waste. This entire meeting will be open to the
public. Today the committee will hear presentations by NRC Staff and
DOE on the viability assessment for repository at Yucca Mountain and we
will meet with representatives from the Nuclear Energy Institute to hear
their perspective on upcoming 1999 high level waste initiatives.
Dr. Andrew Campbell is the Designated Federal Official for
the initial portion of today's meeting. This meeting is being conducted
in accordance with the provisions of the Federal Advisory Committee Act.
We have received no written statements of requests to make oral
statements from members of the public regarding today's session and
should anyone wish to address the committee, please make your wishes
known to one of the committee staff and as usual it is requested that
each speaker use one of the microphones, identify himself or herself and
speak with sufficient clarity and volume so that he or she can be
readily heard.
The committee member that has the lead on viability
assessment is George Hornberger and George will moderate and orchestrate
the discussion that we are going to have this morning.
DR. HORNBERGER: Are you ready to start, John?
DR. GARRICK: Yes.
DR. HORNBERGER: Is Steve here? We are just going to start
right in and we'll hear first from Steve.
DR. BROCOUM: I assume I am on line -- sounds like I am.
Lake was supposed to give this presentation but he is unable
to attend, so they have asked me to speak for him. Lake had prepared
his remarks in detail so I prepared remarks for myself and I guess for
Lake -- Status of Yucca Mountain Project. I understand you wanted to
focus on looking ahead as to looking behind, so I will quickly
summarize.
The Congress had directed us to prepare the viability
assessment, that report, and we issued that report in December, on the
18th I believe, and it gave the status at that time of site
characterization. It identified the key issues that will be addressed
before we can proceed with the site recommendation.
Some of the if you want to call them conclusions or
statements in the viability assessment -- the viability assessment
stated that Yucca Mountain remains a promising site for a geologic
repository. This word "promising" created a lot of debate within the
Department of Energy and a lot of internal discourse before we were able
actually to state that. If you look in the overview, you can get the
exact words.
The mountain has been stable for at least a million years.
Our performance assessment suggests that at least for the first 10,000
years after the repository is closed, people living near Yucca Mountain
would receive little or no increase in radiation exposure, less than a
millirem over the first 10,000 years, and the cost to develop the
repository, on the order of $36 billion, taking all historical costs
into account.
Some of the characteristics of Yucca Mountain, and those who
have heard our repository safety strategy will recognize this is
reworded by similar -- on the whole water moves through the mountain,
slowly percolates at six, seven millimeters a year on average. Little
of this water would contact any waste packages, and that is of course
part of our ongoing research. The waste packages would substantially
contain waste for thousands of years. As you know we are looking at
making the waste packages even more robust than they are today.
If there was a breach of the waste packages there would be a
low release of radionuclides and finally the concentration transport of
radionuclides released from this package would be reduced by adsorption,
dilution, other processes. These four things make up our repository,
the key attributes of our repository safety strategy.
The key uncertainties that need to be addressed before an
evaluation of suitability and therefore site recommendation -- more
information on amounts, the rates, and the mechanisms for water seepage
into the repository. Seepage of water onto the waste package is our most
sensitive parameter in our performance assessment.
More information is needed on the waste package materials
for long-term performance and also we had to recommend that we evaluate
alternative design concepts, which we are doing.
Cladding is an area of intense debate within the program.
How we can demonstrate -- we know we have cladding but how we can
actually demonstrate it at a licensing hearing has always been a big
issue. We need to look at that some more.
Finally, the interaction between the repository and the
natural system, that coupled processes in and around the waste package,
the engineered barriers and the rocks around there is one of the big
drivers for alternative designs, particularly for the very hot
alternatives.
There should have been another bullet on here, and think
there was in an earlier draft, the saturated and the unsaturated zone,
movement of water through the saturated and unsaturated zone after it
leaves the drifts, and you will have some discussion on that today
certainly for the unsaturated zone from Ernie Hardin.
The whole VA was built around our reference design, so that
we had a consistent basis for early analyses of performance assessments
and sensitivity studies, the uncertainty that we presented in the VA.
We are now evaluating design alternatives. I think you heard quite a
bit of that yesterday for the process from Ric Craun. Our goal is to
choose a design to move forward with to site recommendation.
One of the big issues is the temperature ranges. We are
looking five alternatives from a very low thermal load to a very high
thermal load and we are looking at design features that would minimize
contact of the waste with water. The key thing is water here. If we
can keep water off the waste packages, if we can keep water off of the
waste itself, the performance is really enhanced.
Finally, we are looking for design flexibility to allow us
to close the repository as soon as 10 years after emplacement of the
last waste or as long as 300 years after emplacement of the last waste.
The idea here is a recognition that we are not going to be the
decision-makers at the time it's time to start debating repository
closure. There will be other people in my shoes. There will be other
people sitting around this table and therefore that is an explicit
recognition that some future generation will actually make this
decision.
This criteria in some cases may be difficult to implement.
For example, closing as early as 10 years after emplacement of the last
waste puts severe -- could put severe constraints on a thermal load
repository because one of our other criteria is not to raise the
cladding temperature over 350 degrees C., so if you just emplace the
waste and you put backfill in and you close, you would probably not meet
that 350 degree C. cladding criterion, so there's a lot of issues here
and as we come up with alternatives we will have to revisit this
requirement.
The United States Geological Survey did a review of the
viability assessment before it was released. That review was done by
USGS in Reston. They generally agreed that a repository could be
designed and built at the Yucca Mountain, however they raised several
important issues from their point of view. They believe that most of
our models for the flow of water through the mountain are overly
conservative. In other words, they think we have more water flowing
than they believe is the case.
Since in their view we have overly conservative assumptions,
they believe that those overly conservative assumptions have driven our
design and in some cases we may not have an optimum design for Yucca
Mountain, so this is an important thing we need to look at.
They recommended an expert elicitation be completed for
future climate to provide more representative filtration estimates. We
have planned that into our program this year. They believe that a
repository should be designed so performance confirmation monitoring can
be undertaken that is efficient and comprehensive, and one of the major
concerns they had here was that in our reference design we had the
concrete-lined tunnels which they felt would impact the ability to look
at those tunnels once you have emplaced waste.
They recommended also that a cooler repository be
considered, cooler than the 85 MTU per acre that was in our reference
design, so these in a nutshell were the concerns from the United States
Geological Survey.
I need report on another report that just recently came out
or will be out very shortly -- TSPA Peer Review Panel has issued a
report. The report is dated February 11th. I didn't receive my copy
until February 18th. That report also has a lot of comments about the
robustness of our PA. It puts them into three general categories. In
some areas things are very complex and they may be difficult or
impossible to analyze with our current state-of-the-art. In other areas
we may not have enough data and they are very concerned about that, and
third -- let's see. There was a third -- oh, our assumptions in many
cases may not be adequately justified.
Those three areas. So that panel has a public meeting
scheduled for the 17th of March in Las Vegas. So that's some of the
other input that's coming on the VA so far.
Basically what they recommended, so I just finish my
thoughts here, in areas we don't have enough data to get more data, in
areas where things are very complex and they're not necessarily easily
analyzable to be conservative, in areas where the assumptions are not
adequately justified, justify your assumptions or make conservative
assumptions.
So our next steps. We're planning to complete key tests and
analyses to update our process models and to continue to enhance our
design to address those uncertainties. And that will of course be the
new design or the enhanced current design we choose to move forward
with.
We are trying to transition from a
reseach-and-development-type culture to a regulatory culture where we
are the owner-applicant, we're in full compliance with QA and all its
procedures, and all our technical positions are fully documented. And
this is taking a lot of our effort this year.
So we have put a lot of attention on quality initiatives
we're trying to resolve. We have five open concerning data,
traceability, procurement, and so on, and we have reorganized the
project to enhance our quality and excellence.
In my mind VA is history. It was off my table whenever we
got it done; we actually got it done the end of August. It took us a
few months to get it out of the Department. And we focused from the VA,
now we're thinking of EIS, the draft EIS is coming out this year and the
evaluation of the suitability to Yucca Mountain.
We recognize that we have some deficiencies regarding
documentation and traceability of data. We've done several vertical
slices, and that's what the data has told us. And in our process
models, you know, fully documenting and tracing them has been a
challenge. So we developed a plan to become fully compliant with all QA
requirements that we develop appropriate documentation and that the data
is qualified or identified as nonqualified. That means that we're
putting a lot of emphasis on the data we have in house as opposed to
getting new information. Not that we're not getting new information.
But we're paying a lot of attention to making sure that the reports we
put together that support suitability and the suitability of the LA are
fully documented and are fully traceable.
We have undertaken the process validation and reengineering
activity, which we look at all of our technical and business practices
to make sure we understand what we're doing, lay them out, and then if
there's something wrong with them, we're fixing them. So basically for
each key area, technical area, we are in a sense seeing what the present
process is, seeing if it needs improvement, and if it needs improvement,
improving it.
We are hoping, and the goal in fact in doing this is to
minimize the number of procedures we have. We have today overlapping --
numerous overlapping and very complex procedures. In fact, we have
something like on the order of 580 procedures. The goal is to have less
procedures. We have several review procedures. We have several
procedures for each thing we do. What we're trying to do is have one
procedure that all parties could use. And that's part of that goal.
A little bit about organization. We have three key offices,
the Yucca Mountain Site Characterization Office, the Office of
Acceptance, Transportation, and Integration, Dwight Shelor, Acting, and
the Office of Program Management, Dwight Shelor also Acting. This slide
is out of date. Sam retired at the end of December.
We have four key offices at Yucca Mountain, the Office of
Project Control, the Office of Project Support, the Office of Project
Execution, and the Office of Licensing and Regulatory Compliance. These
are the two offices that do all the technical work.
This next viewgraph is just here to show you in addition to
the four offices at Yucca Mountain I talked about -- these are the
four -- the other direct reports to the project manager. We have people
at headquarters that report directly to the project manager. We have a
chief counsel. And we have an Office of Institutional Affairs. I will
talk about the Quality Assurance Assessment Team on my new viewgraph.
The idea here was to set up a customer-supplier type
relationship where the ultimate customer is the Secretary of Energy for
site suitability or the Congress or the NRC for a license application.
My office would define the requirements that are needed to meet that
need.
The Office of Project Execution goes and collects all the
information. For example, they're responsible for doing the TSPA's.
They're responsible for doing the site description. They're responsible
for doing all the detailed technical reports. These two offices are
supported by these offices, Project Control, which takes care of cost
and scheduling and that kind of stuff. The Project Support, all the
other contractual support you need to run the program. And finally the
Office of Quality Assurance has an assessment team. If we need -- if we
have some question about if we're following procedures correctly or
implementing QA correctly or things are traceable, we can call in the
Office of Program Assessment to help to do an assessment, whether it's a
formal QA, order of surveillance, or an informal surveillance to tell us
how we're doing.
As an example, I'm asking this office to come and look at
the process we have for reviewing the EIS to see if it meets our
requirements in the project right now as the EIS is going to major
reviews.
Again, the technical work, these two offices have to work
very closely to get the work done, and the next viewgraph tries to get
at that.
On the right are the key products that will be coming out in
the next few years. For example, this summer we have our draft EIS. We
have a site recommendation, which I'll talk about a little more in a few
minutes. And if suitable, the LA. On the left we have all the detailed
engineering and scientific reports. And the middle is the interface
between the products we need to get out in a sense for our customers and
all the detailed work going on in the project.
So as manager of these key products, what I'm trying to --
these licensing and regulatory products, I'm trying to focus on major
technical reference reports that we can draw on to write our products.
And this is an example of the major technical reference products.
And then -- so my span of responsibility goes from the key
licensing and regulatory products through these major technical
reference reports. Dick Spence, the head of Office of Project
Execution, his responsibility is making sure all the detail work gets
done that supports the production of these major technical reference
products which we need to get out, our major regulatory products.
That's how we're working together so that I, responsible for these
things, don't have to worry about the myriads of reports that are
produced by all national labs, the GS, and within the M&O.
We do have a comprehensive multiyear plan that will lead to
a final EIS in 2000, will provide we hope the basis for collecting
sufficient information for a defensible evaluation suitability in 2001
and if suitable a recommendation to the President that we proceed with
submitting an LA to the NRC. That comprehensive plan was iterally
produced as reproduced volume 4 of the VA. Volume 4 covers a period
from today to license application, and Carol Hanlon will talk about that
in the next presentation.
Our key major products for this year. Since the VA was this
year, this fiscal year, that's on the slide. We have internal draft
right now an annotated outline for the site recommendation. That's due
in March of '99. We are working on the design alternatives which Ric
Craun told you about yesterday. That's due in May of '99. We will
issue our draft environmental impact statement in July. And we have a
working draft license application. We're going to probably change the
name of this to working draft license application outline in August of
'99, because it will not be a full draft LA.
I just put this up here so you could get some idea of the
key milestones coming up. And our next big key milestone is if the site
is suitable for site recommendation. These numerous things on the top
here are all the steps we think we need to go through to issue our site
recommendation. You know, everything from hearings to completing the
hearings, having comment period, concurrence drafts, receiving State of
Nevada comments, receiving NRC sufficiency comments, we now have it
scheduled for 5/25/01, completing our review and issuing it on the 27th
of July.
So that's kind of we've laid out our schedule to do this.
These are the key feeds from science and TSPA, and these are the key
design feeds into the process. So you see we have a lot of detail here
on site recommendation. We don't say too much about LA, because right
now on our near-term horizon for the next two years is the suitability
and site recommendation.
This is kind of in a graphical form how we view our site
recommendation package. The bottom of the pyramid is all the
information we've collected in site characterization. Second layer are
all the detailed reports. Those would have been the ones on the left
side of the document I talked about earlier in general. The third, and
I will talk about this in a little more detail in the next few
viewgraphs, what the site arrangement itself will look like, we'll
probably have an overview, a short recommendation, a letter from the
President to Congress if we ever, you know, get that far.
We're now envisioning four volumes, but as we work through
our outline, we're having a lot of debate on these two volumes here, and
it's conceivable they'll be combined or put in some other order. But as
we see it today, a volume will contain the technical information
required by section 114 of the Nuclear Waste Policy Act. That includes
a description of the design of the proposed facility, a description of
the waste form and of the waste package, and a discussion of the
information collected during site characterization relating to the
safety of the site.
Volume 2 would be our analysis of the suitability of the
site using our guidelines.
Those two volumes would be completed by or around November
of -00 so when we go into hearings, those two volumes would be issued in
draft form for the hearing process and public comment.
Volume 3, which would not be ready in draft form for obvious
reasons, other information required by Section 114 of the Nuclear Waste
Package, the views and the comments of the Governor and legislature of
any state or affected Indian together with the Secretary's response --
obviously we won't get those until after the hearing process, any other
information the Secretary considers appropriate and any impact report
submitted by Nevada to the Department.
Volume 4 would contain the Nuclear Regulatory Commission's
preliminary comments on sufficiency of site characterization, and
finally the final EIS will accompany the SRR.
So the first two volumes are information we, the Department,
can put together with our own internal information, and those we will
release to the public for public comment. Volumes 3 and 4 are
information that we get from outside -- NRC's comments and the State of
Nevada's comments and so on, other states and Indian tribes, so Volumes
1 and 2 would be out for public comment and as the information comes in
we would put together Volumes 3 and 4.
Is that a fire alarm?
MS. DEERING: No, it is an announcement.
DR. BROCOUM: What are our key priorities this year?
The number one key priority is implementing an effective,
efficient program process, validation and hearing process. That is when
we look at all our business and technical processes and make them more
efficient -- develop defensible, traceable and reproducible technical
baseline -- complete our draft EIS and select our design for our
possible site recommendation.
We are conducting detailed planning for how we would
evaluate suitability and a possible site recommendation. That is the
annotated outline I mentioned.
We are conducting investigations on reducing key
uncertainties. Those include the waste package, the saturated zone, the
unsaturated zone, seepage into the drifts -- those kinds of things.
We are going to revise the process models, try to make them
more representative of site conditions for the next iteration TSPA which
would be for the site recommendation.
We are trying to complete the system description documents.
Those are what define the whole design. We need them to do the TSPAs
for the site recommendation.
We are working on a working draft license application
outline -- they've got it right on this viewgraph.
That is kind of where we are at the moment.
DR. HORNBERGER: Did you guys at least take a deep breath at
the end of August after you finished the VA?
DR. BROCOUM: No, because we had a lot of internal -- the
Secretary did an internal review so it was a lot of -- we finished but
then we had to respond internally to a lot of questions and that kind of
thing so it was a small breath but I wouldn't say it was a big break.
DR. HORNBERGER: Do we have questions for Steve? Marty?
DR. STEINDLER: Two things. One, I noticed in this Table of
Organization one of the things that is not clearly evident is somebody
responsible for communicating with the outside world. There is
no relations indication or anything like that.
Does that mean you haven't got the message or that it just
got buried in here someplace?
DR. BROCOUM: If you look -- that is why I showed this
chart, in part.
The Office of Institutional Affairs -- these are the key
offices doing the work and supporting the work done. There is an Office
of Institutional Affairs under Alan Benson. It's his job to do. For
example, now we are having a series of public meetings. We had one
yesterday in Reno and we had one last week in Amargosa Farms -- public
update meeting we call them.
DR. STEINDLER: But my other question is more technical.
In Volume 2 of the site recommendation documents, what level
of detail do you anticipate putting into that in relation to -- as
measured by, for example, the final documents that you would submit for
the license application? Same kind of level or --
DR. BROCOUM: I don't see the same level because if it was
the same exact level, the next day, assuming it was recommended, the
next day we submit a license application.
I view this more as a proposal. You know, it's looking
pretty good. We think we can make it, but we are not the NRC. We can't
say -- but from our perspective it looks like we ought to move forward,
so in my view in these volumes we would have a fairly comprehensive
analysis of the post-closure because that is the -- I don't want to call
it beyond the state-of-the-art but that is the thing that has never been
done before.
We would have a less comprehensive analysis of the
pre-closure design. It would be less developed. I think for an LA the
NRC would of course want more detail on design, on the concept of
operations and that kind of stuff, so certainly in the pre-closure area
I would see less detail here and in the performance assessment area, I
have a lot of detail. It might not be fully traceable to the standards
that the NRC would require for a licensing hearing.
DR. STEINDLER: But you are not going to have enough time to
get any significant amount of additional data so it is a question of
what you already have, the fraction of that you are going to put in the
Volume 2.
DR. BROCOUM: That is correct. One of the things we are
thinking that we are going to do for the TSPA this time around is write
a report for each key process model. That report would contain all the
information -- we are calling them Process Model Reports, PMRs.
We will try to make that report as stand-alone as we
possibly can --
[Pause.]
DR. BROCOUM: Anyway, so these PMRs, we would try to make
them as self-contained as possible so this report and any references to
it will be fully traceable, fully qualified, and fully support those
process models and their abstractions.
We may not have those fully completed for site
recommendation. Right now we are planning eight or nine of those I
believe, and that is all in the planning stage. That is why I can't be
more definitive.
DR. HORNBERGER: Other questions? Charles?
DR. FAIRHURST: Steve, I don't know, maybe I should defer
this to Ernie but yesterday Richard Craun and you mentioned it briefly
here, the high temperature, low temperature, and then you had a third,
which was the enhanced access was a significant consideration.
What I want to know is you mentioned the problem of putting
in backfill and high temperature with 350 C. problem. Is the enhanced
access needed at all for a low temperature repository? It is primarily
a high temperature concern, is it -- because you have to keep the things
open longer and --
DR. BROCOUM: Sure. Well, I mean enhanced site, you have to
be able to put in radiation -- say you had to go in and work on the
waste package --
DR. FAIRHURST: Yes, I know --
DR. BROCOUM: -- you would have to put radiation protection,
that kind of stuff. What we are thinking of now is enhanced access is a
feature that we can add to any option, so it is not -- Ric should have
mentioned that -- it is not being thought of as a third design anymore.
DR. FAIRHURST: No, he didn't say that. He didn't say that.
DR. BROCOUM: Right.
DR. FAIRHURST: I am just saying that from what I heard you
say it seems to me it would be less necessary if it was a low
temperature design.
DR. BROCOUM: I would say it would be easier to implement.
I think we are saying very close to the same thing.
DR. FAIRHURST: Because I am saying -- you have a low
temperature option which I am beginning to think has got a lot of merit
to it, and that two of the other three concerns, the high temperature
and enhanced access, would probably obviously not be required.
But the other thing -- what is the major disadvantage? Is
it a question of real estate with the low thermal?
DR. BROCOUM: It is real estate. It is about double the
real estate, I believe.
DR. FAIRHURST: I understand that.
DR. BROCOUM: It might add some more cost because you are
going to construct more drifts.
It depends on your point of view whether that is a
disadvantage or not. It's really a trade-off.
DR. FAIRHURST: But is there a concern for the real estate
available? In other words, you know, is there a limit --
DR. BROCOUM: There is some concern but I think we're pretty
comfortable. I think even the low temperature will fit in the upper and
the lower blocks.
DR. FAIRHURST: And that is all with a single layer
repository, right?
DR. BROCOUM: Yes, but the blocks would be offset slightly
if you have to go to the lower block but they are not overlapping.
DR. FAIRHURST: Yes. Okay.
DR. BROCOUM: I want to make a comment on that.
The issue here is keeping the waste packages either, as we
like to say, cold and wet or hot and dry -- not warm and moist, and you
have to worry about a thermal profile through time relative to the
materials you have selected and so you have to work all of that out to
make sure you minimize your time in the corrosive regime which is warm
and moist.
DR. FAIRHURST: You don't feel it is possible to have cold
and dry? It's hard to prove. All right.
DR. BROCOUM: It is hard to prove and many people believe
that once you have shut off -- if there is no ventilation and you shut
it off, the relative humidity will go up to 100 percent. Now
dripping -- who knows?
DR. HORNBERGER: Ray? John?
DR. GARRICK: In one of your slides you said as one of your
next steps the project is transitioning from a research and development
orientation to a regulatory culture -- which is kind of a mouthful --
just as the transition to an environmental cleanup agency has been a
tremendous challenge to you.
Are you taking advantage in that transition of the enormous
experience base that already exists in working in a regulatory
environment?
One of the things that I think is very impressive and not
talked about much is the maturity of the nuclear power industry with
respect to the implementation of QA and the whole process that has
evolved over the last 30 years in that regard.
It seems to me there's a lot of expertise out there to help
you in that area and there's not much excuse for not tapping it and not
much excuse for being clumsy about that transition. What are you doing
about that?
DR. BROCOUM: Well, you know, the M&O has brought in several
senior managers that have nuclear licensing experience. Dan Wilkins,
who is Acting General Manager right now, running the whole M&O in other
words -- he's had experience over I think 30 years at General Electric
in the nuclear business.
Jack Bailey, who is a regulatory lead over there, has had
experience. Winston & Strawn, the lawyers that work for the M&O, have
had experience in the nuclear business. They have set up a detailed
training program. It is an all day program that every employee on the
project is required to go to. That is being given right now, where they
actually go through some examples. They even go through some example
hearing type questions and how people had to answer questions and where
they were not traceable, you know, how they lost their credibility, so
there is an intense effort going on I would say for the last six months
here to take that experience and bring it down to the 2000 troops.
Also I believe NEI is going to come in and look at some of
our programs from their perspective and give us some advice as to how we
could better emulate industry.
On terms like "commitment tracking" we are trying to use
industry practices for commitment tracking with the NRC. We visited
several nuclear power plants to see how they meet their commitments to
the NRC, so there is a whole series of activities like that that we have
been undertaking.
I am not sure if we are missing anything, but that is the
kind of stuff that we have been doing so far.
DR. GARRICK: Yes. Well, I think that the fact that a lot
of U.S. plants now are making it into the Top Ten World Performers, and
if you look at those plants that are doing that, one of the contributing
factors is in many instances the maturity of the QA process and the
expanded interpretation of that process, so that was just a thought.
The other thing I noticed, you talked about something that
caught my attention of selecting a design in 1999. Given what we have
been seeing and reading and hearing as to the options and alternatives
and variations on the design, it appears that you are going to have a
tremendous convergence here --
DR. BROCOUM: We hope so.
DR. GARRICK: -- in the next few months --
[Laughter.]
DR. GARRICK: -- and I guess I have a little difficulty
seeing how that is going to happen that quickly given what we have been
hearing about alterative designs and maybe it is just what you mean by a
design.
Yesterday, we had the meeting divided into two categories:
design of a rather basic and elemental nature and design features that,
while there may be an ongoing and continuing change in design features,
the basic design decisions are likely to be forthcoming here. Not that
we believe that you should necessarily freeze a design until you have
what you consider to be a good design, the best design, but we are
interested in knowing what you mean by what you say.
DR. BROCOUM: I think we're more talking about the basic
design, you know, the thermal loading probably, the sizes of the waste
packages, the base materials, you know, whatever the factors the
engineers need to go on, you know, you'll be able to hand it down in
more detailed engineering to do the proper tradeoff, not to have all the
-- I'll call them bells and whistles frozen in May.
Some people say we should only decide whether it's high or
low temperature. There's a big debate going on in the project as to
exactly what the decisions we have to make are.
We've set up an application design integration group that consists of
myself as the chairman, Rick Craun, Dick Spence as the key feds,
Wilkins, Mr. Snell from the M&O is the chief designer, and several other
people, to sit down and decide what decisions we are going to make
because we haven't laid those out exactly. We're working on those right
now.
There's a big workshop coming up in the second seek in March
where the designers are going to get together, you know, and debate all
the different permutations and everything they've been thinking about.
But we're going to make the decisions we have to make to be able to go
on with the process. So we have to make some decisions. We're not
going to make every single decision, but we're going to try to at least
get the path that these designers have to go down. I think that's what
we're basically talking about.
So that's more on the basic side of your discussion.
DR. GARRICK: Thank you.
DR. HORNBERGER: Steve, this isn't the first time, of
course, that we've heard that DOE has some problem, shall we say, in the
area of QA. Now, this time, of course, you're going to assure us that
you're going to solve these problems.
What I'm curious about is -- because again, the time gets so
compressed for doing these things looking at your time line. We might
divide them up into three kinds of problems.
The first kind of problem might be that, okay, there's a
problem with these data because somebody didn't fill out Form 7937
giving the model of the spectrometer or something, not too serious. I
can believe that you could fix those.
Another kind of data problem could be where the person
didn't record a calibration curve for an instrument, and whether or not
you can go back and do that could put the data in real jeopardy.
Then the third would be that the data really are
questionable.
What's your mix of problems?
DR. BROCOUM: The mix is mostly the first two.
DR. HORNBERGER: Okay.
DR. BROCOUM: For example, on a procurement, there are some
cases where we haven't necessarily done the procurements correctly. So
all the data that came out has been out -- labelled as indeterminate.
That doesn't mean it's necessarily indeterminate, but until we sought
that procurement thing out, they were all labelled as indeterminate. So
a lot of our data looks like it's of indeterminate quality when, in
fact, when you look at it in detail, it's not quite that bad. I'm
hoping that's the way -- that's what the evidence show so far.
But, you know, all this work has been done by national labs,
by world-class organizations, so I think from a scientific or engineer
perspective, they followed at least their normal standards. By the
actual standards of QA where an independent auditor has to come through
and be able to trace everything through, you know, and everything is
checked off, we don't meet that test yet, and that's part of -- and it's
a -- for these people, it's a major cultural shift.
I just want to add one more thing to Dr. Garrick's comment
here, and my question is, we also have to put in everybody's performance
standards throughout the whole organization that we have to work these
-- their quality assurance, and we're basically telling people if you
can't work the procedures, we don't want you on the job. I mean, that's
what we're telling people.
A person, if he cannot follow the procedure, either he must
follow it or he must stop work and then go to a supervisor and say, I
can't follow this procedure for whatever reason and change the
procedure. We're instituting that kind of rigor, which we haven't had
in the past.
DR. HORNBERGER: Other questions?
DR. FAIRHURST: Could I follow up? With regard to this
LADIC group that you're going to chair, --
DR. BROCOUM: Yes. The group is in existence already.
We've had quite a few meetings.
DR. FAIRHURST: It would seem to me that you can certainly
come up with a design that's high temperature and low temperature, and
wouldn't propose either of them if they weren't able to meet what appear
to be the, you know, regulatory standards. But in the long run -- so
technically, I think you can do either. But in the end, it's still
going to be some political public persuasion type of decision. And
doesn't the fact that every other country in the world is looking at low
temperature options give you some pause if you propose something that's
not that way?
Admittedly, you've got a non-saturated zone. Everybody else
is saturated. I know the arguments. But nevertheless, to the person
outside, doesn't it say that we're doing something very different than
everybody else and we're going to have a hell of a job just to --
DR. BROCOUM: Well, let me just talk about the LADIC. The
LADIC is there to do policy decisions. In other words, we're not going
to do tentacle decisions that the engineer should be --
DR. FAIRHURST: Okay.
DR. BROCOUM: The engineers will do their various tradeoffs
and come to us, and then any policy implications we will decide. So
we're not trying to take the engineering away from the engineers.
Secondly, yes, that issue is a very important one. I mean,
you know that Nye County has recommended a ventilated repository, okay,
so we have to --
DR. BROCOUM: The USGS has opted for -- the USGS has
suggested cool. The TRB has suggested strongly that we look at a cool
repository because of the analyzability problem. In other words, it's
easier to analyze. As you know, Lawrence Livermore for many years has
been a proponent of a very hot repository because they want to keep the
water away from the waste. And so these are some of the -- you know,
and that's probably been for the last ten years.
So we have to weigh all of these things, and the question
is, you know, is it easier to make the licensing case very hot and keep
the water away with all the uncertainties we have about analyzing a
system, or is it easier to have a cooler repository that's easy to
analyze but maybe not as easy to argue that we're going to keep the
packages dry all that time. I don't know what the tradeoff -- but those
are the kind of things that we're going to be facing in making those
decisions.
DR. HORNBERGER: Steve, your view on that particular issue
is keeping it dry, the advantage being the thermal period keeps
everything dry. The NRC staff has some concerns that I've heard
expressed that you people don't take into account the reflux during the
thermal period, that there are data from your own tests that suggest
that it won't remain dry during the thermal period.
DR. BROCOUM: That is -- the original concept of our current
-- one of the original premises of our current design is that we would
keep it dry during the high thermal load period. The reflux would occur
after that when it isn't so hot anymore, 3000 years or more after. But
the premises on the two low thermal designs are in one design, we keep
it under 96, and therefore the rock temperature never goes above
boiling; and the other design, the second design, though, we keep
between the pillars under 96 so that it can drain.
That has become an important issue for us. It may be easier
to make that kind of an argument than to make some kind of an argument
we're going to get some kind of, you know, clogging of the pores above
it and creating a cap, which is the argument that the people for that --
you know, some of the people are making for the high thermal designs.
These -- again, we're going to have to decide these things.
These are going to be decisions we have to make coming up in the next
few months.
DR. FAIRHURST: Does that push you to wider pillars?
DR. BROCOUM: I believe that the lowest thermals I heard,
yes, the drifts were 70 meters apart.
DR. FAIRHURST: Yes.
DR. BROCOUM: Versus I think 28 today in a current design.
DR. FAIRHURST: Yes.
DR. BROCOUM: So that makes a difference in the area, that's
correct. But again, we don't want --
DR. FAIRHURST: Well, I'm not sure it's necessary.
DR. BROCOUM: If we decide, for example, to go with option
1, which is a very low thermal design where we don't let the rock get
over 96, we're not going to specify exactly; we'll then let the
engineers go do their various tradeoffs and they'll come back and tell
us what they think is the best. So we're not going to arbitrarily set
these things up as limits arbitrarily, okay; we're going to have to try
to have engineering studies and system studies to help us optimize the
system.
DR. HORNBERGER: Okay. Thanks very much, Steve.
DR. BROCOUM: Okay.
DR. HORNBERGER: We will continue our presentations. Let's
see. Carol, you're next.
MS. HANLON: Good morning. I'm Carol Hanlon and I'm here
today to discuss with you Volume 4 of the Viability Assessment -- that
is, the license application plan. I apologize that we're a little late
in giving you this presentation. I think it would have been useful to
you to have it earlier. I wish that it happened, but hopefully it will
be of some value to you today.
I would like to just call your attention to some changes in
the order that you will see in your agenda today. Dr. Ernie Hardin is
here also to follow me. Ernie spoke with you in December about the
prioritization of the principal factors. Today, he will also review
that prioritization, especially as it pertains to three highest priority
principal factors, those of seepage, flow and transport through the
unsaturated zone, and corrosion of the inner barrier materials.
In addition, Dr. Dwight Hoxie from the USGS will be here to
give you specific details on the plan for seepage, flow and transport
through the unsaturated zone; and Dr. David Stahl will be here to
discuss with you waste package corrosion inner barrier material
corrosion.
So I think it's helpful as we discuss the license
application plan if we go back to the purpose for that plan that was
envisioned in the civilian radioactive waste management program plan,
and that was that this plan would identify the remaining scientific
investigations and engineering information that would be needed to
complete the license application, with our long-term goal being
submittal of a docketable license application to the Nuclear Regulatory
Commission.
In addition, the program plan called for is to identify the
cost associated with securing this information.
With this purpose in mind, the intended use of the license
application plan was to provide the public with the understanding of how
the department had identified, prioritized, and described those major
areas of work remaining to be conducted during the next four years, also
with the goal, of course, of a docketable license application, and to
present the schedule and the cost for those work activities identified.
In addition, we discuss the statutory and regulatory
activities and supporting work for completeness briefly.
In reviewing the license application plan, I think it's
helpful to keep in mind that it was not intended, I think as Steve
mentioned earlier, to provide a lower level details on those work
activities identified. Those details are in both our annual work plans
and our multi-year planning system.
In addition, work plans and procedures will be developed and
they will be identified in individual work packages that are available
in the record system.
The license application plan also is not intended to provide
detail on the statutory, regulatory or support activities, such as
quality assurance programs, site recommendation and license application.
Those details are provided in separate management documents which are
specific to each area, such as the license application management plan
and the quality assurance requirement description.
So with that as a background, I would like to turn to the
organization of Volume 4, license application plan. It draws, of
course, heavily from the other volumes of the VA -- site description in
volume 1, the reference design presented in volume 2, and TSPA-VA
presented in volume 3.
There are seven sections of the license application plan, an
overview, rationale, section 3, technical work plans. Those are the
most important things, I really believe, from our standpoint.
In addition, we have a fourth section on statutory
activities, including EIS, environmental compliance, site suitability,
site recommendation, license application. We have a section covering
the support activities that go in the field to support the activities
that we're conducting. Six and seven are also very important -- the
cost for the license application and the schedule.
Again, I've highlighted those areas that I believe to be of
most importance. Those are the overview because it's a good
introduction and it puts things in perspective, the rationale for the
work needed to complete the license application, especially with the
postclosure safety case, the prioritization of the principal factors and
the description, and the technical work to follow those up.
So our areas of emphasis are those five -- the rationale for
the technical work needed to complete the postclosure safety case, the
postclosure safety case itself, expected postclosure performance, the
principal factors of postclosure performance, and technical work plans.
In section 2, the license application plan rationale -- we
gave a great deal of emphasis to this rationale because of its
importance in identifying the work needed to complete the postclosure
safety case and the preclosure safety case and take us toward our goal
of a docketable license application.
The information that we have acquired during more than 17
years of characterization at Yucca Mountain has been incorporated into
the site and design process models. That information was also used to
develop both a TSPA-VA for the viability assessment, and the repository
safety strategy. That safety strategy is actually considered the
framework for integrating our information on site, design and PA.
Now, both of those, the TSPA and the repository safety
strategy, were used to build the postclosure safety case. Similarly,
the information for the design and process models was used to develop
our operational considerations and design basis events and those were
used to build our preclosure safety case, which is roughly analogous and
similar to the postclosure safety case but actually quite different.
The postclosure safety case has five elements. The first is
the assessment of expected performance. The second is design margin and
defense-in-depth. The third is consideration of disruptive processes
and events. And those actually work very closely together to give you
your expected performance. The fourth element is the insight from
natural and manmade analogs, which gives us the opportunity to look at
other existing sites that have existed over long periods of time and
have spacial variability to see how that confirms what we're finding.
Finally, we have the performance confirmation plan, which
will be our plan through the long term to continue to monitor what's
happening and draw conclusions from that.
Preclosure safety case is a bit similar to that. The
systems evaluation of the design basis events is roughly analogous to
postclosure performance. Classifications of structured systems and
components may be really the design features, defense-in-depth,
verification of system design and use of demonstrated technology.
Now, for all of those elements of the postclosure and
preclosure safety case, the viability assessment discusses the status of
the current -- our current status of the information that we have. With
the postclosure safety case, we'd go through each of the elements and
present the information, a summary of the information as we have it.
For the preclosure safety case, we'd talk more about the processes and
how they will unfold.
We also talk about information that will be needed and the
technical workplans to acquire that information in summary fashion,
leading on forward to the workplans themselves.
In the case of the assessment of expected performance, we've
taken another step with the 19 principal factors, and that is to assess
those principal factors which are culled out both in TSPA and the
repository safety strategy, to prioritize them in terms of the order of
their importance.
DR. GARRICK: Karen, in the preclosure safety case are you
making a distinction between a 100-year open repository and a 300-year
open repository? We haven't -- of course we're not involved in that,
and we haven't seen anything specific. But --
MS. HANLON: No, I don't think we call that out clearly --
DR. GARRICK: Right.
MS. HANLON: In the --
DR. GARRICK: And in the preclosure safety case, are you
actually doing performance assessment in the sense of performance
measures similar to the postclosure case, that is to say, are you doing
dose calculations?
MS. HANLON: No, it's a little bit different. It was hard
to make it fit into the same paradigm as the postclosure. And so as I
said it's roughly analogous, but it's not as rigorous as the
postclosure.
DR. GARRICK: One of the real interesting outcomes of this
whole process would be the revelation that the preclosure risk is much
greater than the postclosure risk, and I don't get the sense that this
is really being addressed. But we can talk about that later.
MS. HANLON: And that's also one of the things that we've
been reflecting on that has been called to our attention recently, and
we're taking steps to address that also, Dr. Garrick.
So with the 19 principal factors, they were prioritized, and
this was for the purposes of identifying the technical work with the
best potential to reduce uncertainty in the postclosure safety case.
And consideration was given to the factors to which the peak dose rate
was most sensitive. This work has consequently received priority
funding and resource allocation.
To recall some of the prioritization considerations that we
used in this prioritization and that Ernie discussed with you in
December, I'll just go over briefly three factors. Our consideration --
is that straight? -- our considerations first of all were the
significance of these uncertainties to the total system performance
assessment, the effect of the uncertainty on the peak dose rate
calculation, and that was classified as high, medium, and low.
Secondly, we looked our current confidence in what we knew
about that factor and rated it from 1, which was a low, to 7, which was
high. Our question here was is this current representation realistic
and does it capture the entire range of conditions which are important
to performance.
Thirdly, we looked at the confidence goal, again ranking it
from 1, low, to 7, high. Not only did we look at the desirability and
the significance to TSPA and the importance of these factors or the
information to defensibility of technical basis, but we also looked at
the feasibility of being able to accomplish the studies in time for
input to the site recommendation and license application.
So our priority then ends up being a simple subtraction of
the confidence goal minus the current confidence.
Just to show you a summary slide here that's out of the
license application plan, we've taken the principal factors in this
slide and correlated it with the repository safety strategy attributes
they correlate with for each of the principal factors we have discussed
the significance of uncertainty, high, medium, or low, then have
presented the current confidence and the confidence goal.
This summary slide shows then the priority of each of these
ranked from zero to 3; 3 of course means they're of very high importance
and have a high priority, and zero means we're closing in on where we
would like to be.
I think an important point for these is that for all of
these 19 principal factors work will be done. So these are all
considered to be very important. Work will be done for all of those,
but on the 2's and the 3's, that's probably where our highest emphasis
will be, because they pertain most to the performance of the site. And
this came out, just for that purpose I have taken the liberty of bolding
those highest-priority items, the 2's and 3's you can see on here,
percolation to depth seepage and so forth, and our subsequent speakers
will discuss seepage into the drift with you, flow and transport through
the unsaturated zone, that will be Dr. Hoxie, and integrity of the
corrosion-resistant waste package barrier.
So that prioritization and rationale in section 2 then led
us into section 3 where we present the technical work plan, and then
Steve also discussed, we had an ongoing multiyear planning effort that
was going on throughout the whole course of developing the license
application plan. That was somewhat similar -- that was very similar to
the efforts we have had ongoing through the years, and it identified the
work that we have evaluated as being necessary to do.
And with the prioritization effort, we took another look at
that multiyear planning, and based on the prioritization and what we
have said were our most important areas, we've really looked at that
work. So we've crosscut that and attempted to show what was really
essential, what must be done for the license application docketability,
and also what was less important and actually could fall off.
So our technical work then is organized by three functional
areas which won't surprise you -- the site investigation, the design,
and the performance assessment -- and what I'd like to tell you about
this is there are a couple things here. You can see under site
investigation that that's where we have put the fourth element in
discussion of the fourth element of the postclosure safety case, and
that is performance confirmation. We've also put our management areas
there.
You can see on the site investigation and design that there
are eight tables, summary tables, that we have identified there, and
those tables are for the purpose of making it clear and more easy for
the reader to understand where the work is being done and what it
correlates with.
This is an example of that table, just to walk you through
it. We take the work category from the text and we correlate it with
either the postclosure or the preclosure safety case. In some cases it
may correlate with both. We then discuss which principal factors it
applies to under expected postclosure performance with a priority for
the SR and the LA. And then we also discuss the design, what other
elements of the postclosure safety case that particular work may apply
to. We also correlate the work category with the PSS activities, the
project summary schedule activities, which are presented in chapter 6,
especially in Table 6-2.
So throughout the document we've tried to make it easier for
you to understand things by going forward, forward referencing even back
to earlier volumes such as the design in the TSPA and referencing
forward to where later we will discuss cost and schedule.
Because our later speakers are going to be talking about the
discussion of seepage and transport and flow, I have shown you this
example in your package of unsaturated zone processes, because it does
pertain heavily to both seepage and flow and transport. And I've also
included waste package corrosion process from the design chapter.
There are no tables -- actually there are no similar tables
in the performance assessment section. That did not lend itself so well
to actually correlating it, and it was rather redundant, so we made the
decision that that wasn't particularly useful there, and we didn't use
that.
So that is basically our chapter 3. I'd like to call to
your attention a couple of other things. We've had concerns over the
DOE's consideration of key technical issues, and we have considered
them, attempted to consider them throughout the viability assessment in
all volumes they are mentioned, all four volumes. Site design, site
description, the design and TSPA all reference the key technical issues
where they are appropriate; a license application plan goes a bit
further. Wherever we discuss technical work in a chapter or section 3,
we correlate those work activities with the specific key technical
issues that they will address.
We also have a table, 4-2, that shows the location of the
information related to key technical issues throughout the viability
assessment volumes. And in section 4-3 we discuss the key technical
issues, what the status we believe of our work to address those are, and
we discuss the interactions we've had with the Nuclear Regulatory
Commission staff on those key technical issues. So we've tried to
include those.
This is an example. This is the Table 4-2 that I mentioned
that proves useful to you.
So a question actually is how have our priorities evolved as
we were addressing the license application plan and developing it. And
basically we've evolved from an effort in learning about Yucca Mountain
over the last 17 to 20 years to develop the knowledge base for Yucca
Mountain, we've evolved from that to beginning to confirm the knowledge
base and reducing the uncertainty in key areas. So we're also moving
toward maturing the design and performance assessment to the levels
appropriate for site recommendation and license application.
In addition you'll see in the following slide I will show
you that we have established higher confidence goals for the engineered
system in the license application plan that we have in previous plans.
The confidence goals we are showing for the engineered system are as
high or higher than goals we show for the natural system, and that
indicates a higher priority on several aspects of the engineered system
than we may have had in the past.
So as our understanding of the natural barriers is
increasing, our efforts are also shifting to maturing the engineered
system and the performance assessment.
To reiterate this slide, I put a box around those factors
that pertain to the engineered system, and you can see that in fact they
do have among the highest priorities, and they are as high or higher
than the system -- excuse me, the natural system priorities.
So just to recap, we've looked at our goal of a docket of a
license application, and we feel that it's very important to have the
comprehensive safety cases to do that and a detailed rationale for
additional work, which we feel that we've provided not only by including
the repository safety strategy attributes but the prioritization of the
principal factors.
We've included the technical work remaining to be completed,
and the postclosure safety case receives strong emphasis. Regulatory,
statutory, and other activities are included for completeness but are
developed with lesser detail, as I've said, because they are -- the
details are contained in other documents. And we've given consideration
to key technical issues throughout.
So with that as an introduction, I'd like to answer your
questions and then turn it over to our next speakers.
DR. HORNBERGER: Thank you, Carol. Let me start. I have
the impression from looking at the prioritization that your confidence
goals, at least in some cases, were quite heavily influenced by what
people thought could be accomplished in a timely fashion for the license
application. Is that a fair assumption?
MS. HANLON: Yeah, I think that is a fair statement, a fair
assumption, and there was a quite a bit of discussion and debate about
that. In a perfect world, you would like to say I have to have this, --
DR. HORNBERGER: Yes.
MS. HANLON: -- and I have lots of time to get it. But
because we are looking at our goal of the license application in four
years, we also felt constrained to look at our ability to acquire that
information during this period, knowing also that we were relying on
natural analogs for confirming information and the fact that we would
have a performance confirmation plan that would follow, actually, the
results as we went out. Also, that we would have a long time in -- a
longer time in the license application process to reflect on additional
information as it evolves. So, yes, we took that into consideration.
DR. HORNBERGER: Okay. And given your answer, is it then
safe for me to infer from your answer that you don't think that there
would have been major changes in that list if you had been looking at a
14 year rather than a four year timeframe for license application,
simply because you have all of these other performance confirmation
periods built in?
MS. HANLON: I think we have roughly the same set that we
would have had. Ernie may like to confirm or deny that, to show areas
where we might have separated.
DR. HORNBERGER: Okay. Other questions? Marty.
DR. STEINDLER: The general notion of a performance
confirmation time period during which, in fact, DOE is going to acquire
additional data to support a previously submitted license application
represents an interesting approach to the issues of licensing. It is
not normally the way the process runs. What assurance do you have that
that is, in fact, what the NRC is likely to consider to be sufficient as
a methodology of getting a license?
MS. HANLON: I didn't mean to say that we would submit a
license and add additional information through performance confirmation
to make that acceptable. What our intention has been throughout this
process, as I have said, is to look at what the requirements are for a
docketable LA and make sure we had those requirements. And that is why
we went through what may be considered a rather tedious rationale
process to identify the repository safety strategy and go through the
performance, expect a performance of principal factors and say these are
the most important and this is the work I am going to do. So that was
all aimed at giving a docketable license application, a complete or an
acceptable license application, if you will.
Then ongoing, as the NRC has asked and requires of us, is
the fact that there will be a performance confirmation. Some of those
tests like the heater tests were started -- have already been started,
started some years ago. They give us the body of information that
allows us to evaluate what we have put together and see if we are still
on course for that, or if we are seeing things that are unexpected in
the behavior.
DR. STEINDLER: All right. So your -- the term performance
confirmation is not quite what I thought it was. Fine.
You indicated four years in one of your slides, and unless
my arithmetic is faulty, which it may well be, I have only got three
years.
MS. HANLON: In '98, I think we had four.
[Laughter.]
MS. HANLON: The seconds start ticking.
DR. STEINDLER: That's not bad, but as soon as you write
four years in 1999, I begin to wonder what kind of a licensing process
you are envisioning, was the basis of the question.
MS. HANLON: Oh, Dr. Steindler you are so good.
DR. STEINDLER: That's it.
DR. HORNBERGER: Other questions?
DR. FAIRHURST: I just wanted to pick up on what Marty said,
and I am not sure where we are at with this. But given the fact that
we, or anybody will have, presumably, 50 to 100 years of pre-closure
activities, doesn't it make imminent sense to build into that
performance confirmation the gathering of information and feeding it
into a process? Admittedly, you have got a license application now.
But if you found out something terribly adverse, you should be open to
the fact that it is -- one has got to do something about it. Maybe it
wasn't a good idea, maybe, because you have the option of retrieving
everything over that 50 to 100 year period. And, you know, in the EPA,
dealing with WIPP, there is sort of a continuing recertification every
five years.
I am not saying it is something you should do here, but
there is a notion of certain information keeps -- as you mentioned
yourself, the heated drift experiments, well, they will star to cool
down over a four year period, but it probably will continue going on
beyond that, and it could be useful information.
MS. HANLON: That's really what we are looking at, and the
idea of improving information, additional information. As one of the
gentlemen, I think in your last international conference, one of the
gentlemen discussed the fact that with the design, we wouldn't be
getting the perfect design, we wouldn't be getting the best design, we
wouldn't be getting the most inexpensive design with the first design
that we put out. We perhaps might not even -- his suggestion was we
might not even strive for that because, with the information we found
out about how the repository worked and how the design worked, we would
surely be coming up with things that made it -- that -- improvements we
wished to incorporate later. So I think that is just your point, Dr.
Fairhurst.
DR. HORNBERGER: Ray?
DR. WYMER: No questions.
DR. HORNBERGER: John?
DR. GARRICK: I just wanted some clarification, I guess. I
thought the prioritization was extremely interesting and helpful of the
whole process. The thing that I am not sure about is roots. There is a
tremendous effort in establishing an analytical process that manifests
the performance of the repository and that effort is culminated through
something called a TSPA. And yet I get the sense in this prioritization
process that the TSPA played a relatively minor role. In fact, I think
I heard you say something to the effect that when you developed the
various priority -- prioritization lists, that you didn't do the same
thing with respect to the TSPA.
Well, what am I missing? I thought the TSPA was the
instrument or the logic engine for establishing compliance and, yet, I
just don't get the sense that these kinds of information are really
strongly rooted in what the analytical process is evolving as the
primary issues and priorities. To have priority as a confidence goal
minus a current confidence, and to have these confidence on a scale of
one to some number, this all sounds relatively conceptual and subjective
against a background of tremendous analytical process that is ongoing
with very capital-intensive effort. What am I missing?
MS. HANLON: I shouldn't have left you with that impression,
because the two efforts, the TSPA effort and the prioritization effort,
worked very closely together. In fact, the people that were
instrumental in working both of them were working closely together.
Even as we developed the first prioritization in early drafts, the
people working on that were in close communication with the people doing
the TSPA, so that information was going back and forth, and that is why,
in fact, I did include the one slide on the high, medium and low. Ernie
is going to also add something to this.
But when we went through the next step of taking the draft
and having the DOE review of that, we worked very closely. We had an
independent peer review -- if you will excuse me, I shouldn't say
independent peer review. But we had an independent review of our
prioritization, and in that we pulled in people from Sandia, the
performance assessment persons and we looked very carefully at what
performance assessment was saying versus what our prioritization was
saying to make sure they were entirely in sync and, in fact, TSPA was
driving that. So I didn't mean to leave you with that. They were very
integrally tied.
Ernie, did you want to say something else?
DR. HARDIN: I will just add to that real quickly. Ernie
Hardin, M&O. Yeah, for the current confidence assessment that we made,
the significance of uncertainty to TSPA was included in that. And,
also, we recognize that the PA was being used to generate quantitative
results based on a set of conceptual and process models, and, yet, that
set was not necessarily complete, and so our judgment was needed to
establish current confidence.
DR. GARRICK: Yeah, go ahead.
DR. STEINDLER: Let me make a comment in addition to yours.
I looked fairly hard at Volume 4, and I had the same problem you did,
John. I thought that DOE confused the ability to obtain data with the
priority system, and the things that I was looking for, for example,
some measure of how important the seepage issue is, and the models that
go with it, you are almost silent on model uncertainties, for example,
in the prioritization process. I had a lot of problems trying to figure
out just how you got to your priority structure in relation to the
output of that performance assessment.
Let me give you one example -- I'll give you two examples.
The neptunium solubility turns out to be, you know, coming out of the
chemistry domain. If you are off by, you know, not only three orders of
magnitude, it isn't very clear that the data are really any good. It
seems to me -- and neptunium keeps showing us as a fairly important
long-term issue. It seems to me somebody would pay some attention to
neptunium. You assigned it priority one, and knowing how much you have
got to do between now and the three years that are going to pass, it may
never see the light of day. And so I look at it from the standpoint of
that priority is going to get buried someplace that isn't even arising.
The other point that I would raise for you is I am not an
expert in this business, but I gather the biosphere transport and uptake
activity which you have as a zero priority, because you are convinced
that it is correct, was the subject --
MS. HANLON: No, I didn't say that.
DR. STEINDLER: Well, your confidence goal is five and your
current confidence is five, and I guess my implicit assumption is that
you are convinced it is correct. I know you didn't say that. The sense
that I get is that, you know, there may be a fair amount of problems
with that one, judging by the noise that I have heard out of someone of
your review panels.
So, I am wondering whether or not this assessment of your
confidence, coupled with what I sense to be a disconnect between,
basically, the point that John was making, is going to give you a
structure for future activities in the upcoming few, very few years,
that will lead you to where you want to be when somebody finally says,
okay, let's put a staple through that license application and mail it
out. I am a little concerned that there needs to be some more in-depth
look to see whether those priorities are really likely to meet the needs
of the end product. Comment, rather than a question.
MS. HANLON: Steve.
DR. BROCOUM: This table that Carol talked about has created
a lot of discussion, and I would say a lot of controversy.
DR. STEINDLER: I'll bet.
DR. BROCOUM: I want to make a couple of comments on that
table. That table was designed around the reference design in the VA.
We will probably modify that design come this May or April. It is my
intent also that we revisit that table to see what change that we need.
Even as we were completing the VA, in fact, Volume 4 was the hardest
volume to complete, we had a lot of difficulty and a lot of internal
debate in getting that volume done. But there was a lot of debate about
that table because, you know, even in the reference VA, we have
different options for drip shields and backfills and ceramic coatings
and those kinds of things, and if you add those, that table changes.
Yet, we decided that we would stick with our reference design and make
that table match the reference design. But as that reference design
evolves, or as we add or subtract features, we need to revisit that
table. So I just want to make that comment.
At the time, it was the best we can do, when we put that
together, but we realize there are some weaknesses in the table. We did
it in a relatively short period of time, but we did try to balance the
people. We had people from both DOE and the M&O on that committee
representing, in equal amounts, science, engineering and PA. So, but my
expectation, we will revisit that table as we more -- better refine our
design.
DR. GARRICK: Yeah, our concern is not that you shouldn't
try to make the table, in fact, that is a very good idea. The questions
that we have are primarily related to the basis.
MS. HANLON: I think, Ernie, did you have something else
that you would like to add?
DR. HARDIN: No.
DR. GARRICK: Ray?
DR. WYMER: Yeah, I have just a comment, Carol, I don't know
that it is a question or not. One of your prioritization factors here
is that it should be feasible, whatever you are trying to do, it should
be feasible to be accomplished in time for input to the site
recommendation and license application. In light of all the discussion
about the importance of getting additional data in some areas, it seems
to me that maybe the cart and the horse got turned around there a little
bit. If you need the data, you ought to go get it, take whatever time
it takes to get it. Are you being driven too -- I guess there is a
question -- are you being driven too hard by your schedule?
MS. HANLON: Well, that is, again, always the question, and
that is a controversial -- that was a controversial discussion, you
know, the flexibility to accomplish in time for input. So, but in order
to meet our milestones, we thought that we needed to look at that, so
you are right, it is difficult.
DR. HORNBERGER: Other questions?
[No response.]
DR. HORNBERGER: Okay. Carol, I take it from your comments
that Ernie is going to go next.
MS. HANLON: Ernie is next. Dr. Hardin will revisit our
review of the performance prioritization and introduce seepage and the
other discussions. DR. HARDIN: Can everybody hear me okay? Good.
I am the -- I have a responsibility for the near-field
modeling in the M&O, and Dwight Hoxie and David Stahl have similar
responsibilities in the area of UZ hydrology and material science. And
that's why we have asked them to come and answer your questions and
present that material to you.
So I'm going to just quickly revisit the prioritization for
the three highest priorities that I talked about in the briefing in
December. Recall that this prioritization is for technical work for the
postclosure safety case. Other technical work is in the LA plan,
particularly for preclosure safety, for design, and for PA. The
prioritization is based on the VA design, so it's conditional in that
sense.
The process, there's really not a whole lot more I can tell
you about the process beyond what Carol has reviewed for you this
morning, except to say that we had a constituency from the different
groups in the M&O, from science, from engineering, from management, and
that we applied judgment where we needed to and we tried to make full
use of the TSPA analytical models, recognizing their limitations.
So I'm going to talk about three priority items on your
list -- drift seepage, UZ flow and transport, and integrity of the inner
corrosion resistant barrier.
As I'm sure you heard yesterday, some of the design
alternatives are on the table right now in the design selection process
involved waste packages that put the corrosion resistant material on the
outside of the package, and David Stahl can address some of the
differences between those approaches.
For seepage, applying the TSPA model we found that we could
get variations of 50-fold in the calculated peak dose rate postclosure,
and let me say that the way that the TSPA models -- process models and
abstractions were used varies a little bit among the principal factors.
In the case of seepage, what we're looking at is an
equivalent continuum model in which water percolation is diverted around
underground openings. If we look at the range of uncertainty on the
input parameters to that model, and if we also include consideration of
the intersection of the percolation flux with the intersection area of
the opening, this is how you get to 50-fold variation in water that
seeps into the drift.
Our current confidence in the assessments on seepage is
fairly low. The seepage model is calibrated against preliminary data;
the model geometry is circular, whereas we know that rockfall will
change the opening geometry; and the stochastic models used to describe
the variability in properties that represents the fracture network have
associated inherent uncertainties.
The confidence goal, of course, is moderately high because
we have several testing programs that will support those models by the
time we get to SR and LA, and so the priority is high, although we
recognize that some of the tests will be completed concurrently with
preparation of the LA.
And what those tests consist of, very briefly, there will be
two additional alcoves excavated in the cross-drift, with the recently
completed cross-drift in which additional niche studies will be done.
Two fracture-matrix interaction tests are also planned for
the cross-drift.
There's a large-scale seepage test planned where the
cross-drift passes over the main tunnel with an intervening distance of
about 15 meters.
Monitoring of moisture conditions in the wall rock around
recent excavations and in at least one drift, alcove 7, that's been
closed off, will continue.
And geochemical and isotopic measurements that pertain to
percolation primarily, and this includes the chlorine-36 program, will
continue and be completed.
And finally the percolation and seepage models will be
updated.
For the unsaturated zone flow and transport factor,
sensitivity analyses using the TSPA models for VA show that we could
obtain 100-fold increase in peak dose rate. And this is particularly
true if you consider early time failure, juvenile failures of a few
waste packages where you have a localized source and you're trying to
capture the performance of the site using a rather coarse -- relatively
coarse model.
Current confidence is low because of these numerical mixing
and dilution effects, and also because the thermally driven coupled
process changes in transport properties of the unsaturated zone are not
included in the VA assessment.
The confidence goal is moderately high, mainly because we do
have ongoing and planned testing programs that will help support the
models that we take to SR and LA for UZ transport.
The priority is high, but again we recognize that some of
the testing will be completed concurrently with preparation of the LA.
The technical work plans for UZ flow and transport. Well,
these include completion of the testing program in the Busted Butte
facility, which has been ongoing for more than a year.
In addition, transport studies using multiple tracers and
multiple injection points and multiple observation points will be
completed in the cross-drift.
We will take another look, a more comprehensive look, at
natural and man-made analogs to radionuclide transport.
And we will update the mountain-scale models.
For the principal factor for integrity of the inner
corrosion resistant waste package barrier, the uncertainty analysis
using the TSPA VA showed that we could obtain greater than 100-fold
uncertainty in calculated dose rates based on a wide range of
uncertainty in the corrosion rates and the mechanisms for barrier
corrosion.
The current confidence in the TSPA VA model treatment of
this barrier is moderate, only moderate, because of process-level
uncertainties, and because we're using corrosion data that were
developed from laboratory corrosion tests done under a very wide range
of chemical conditions including some very aggressive conditions, and
those data were composited and combined with expert judgment to
formulate the distributions that were used in TSPA.
Our confidence goal is high, because we believe that there
is strong potential for gains in confidence from the ongoing testing
program.
So the priority is high, and this is reflected in planning
of the technical work.
Technical work plans that Dr. Stahl will address include
long-term corrosion, continuation of long-term testing of nickel-based
and titanium-based alloys and multiple material interactions such as
tuff against CRM.
In addition, there are models -- predictive models,
mechanistic models being developed for localized corrosion and phased
segregation effects, and these will be supported to the extent
practicable by measurements and observations.
Passivation effects are being measured and testing will
continue to evaluate microbially-induced corrosion which I understand
has not yet been observed on the Alloy-22 CRM material.
That is all I have. After any questions you may have for
me, I will turn it over to subject matter experts in these two areas.
DR. HORNBERGER: Okay. My suggestion is going to be that
after we ask Ernie questions we take our break now It's a natural place
to break -- and then come back and hear the three technical
presentations and keeping in mind that we are going to hear more
technical detail on the three items that Ernie outlined, I would suggest
that any real detailed technical questions we have would be better left
for a little later.
With that caution, I invite questions.
DR. FAIRHURST: Let me ask this one quickly. Ernie, are you
going to be here later?
MR. HARDIN: Yes.
DR. FAIRHURST: Okay. Then we can ask questions -- we can
bring Ernie back on the stand?
DR. HORNBERGER: We can bring him back, yes.
DR. FAIRHURST: Yesterday people from DOE had to leave.
DR. HORNBERGER: Yes. Marty?
DR. STEINDLER: When you say fifty-fold variation in dose
rate, you are talking peak dose rate?
MR. HARDIN: Yes.
DR. STEINDLER: You don't say anything about what the shape
of that curve looks like in the first, say, 10,000 years where the
period of compliance ends.
MR. HARDIN: Right. There was --
DR. STEINDLER: Did you pay no attention to that? Is that
not a part of the driving force for your prioritization process?
MR. HARDIN: Well, let me just say upfront that generally
the dose rates associated with the first 10,000 years of the performance
period are much lower than the peak dose rates -- as I am sure you have
seen from some of our products.
DR. STEINDLER: Yes.
MR. HARDIN: And that -- but there was a strong, there was
considerable attention given to peak dose rates over a million years in
this prioritization process.
We did, in exercising the TSPA models, we parsed out when --
that being zero to 10,000, 10,000 to 100,000, or up to a million -- when
the peak dose rate was calculated to occur.
DR. HORNBERGER: And you also, when you parsed that, as I
recall, you indicated -- you broke down where the processes were
important in giving that dose and my recollection is that these three
turn out to be important in the zero to 10,000 year period as well as at
the peak dose, is that correct?
MR. HARDIN: Yes, that is.
DR. STEINDLER: What I am trying to find out is whether that
startling factor of 100 or factor of 50 or whatever --
MR. HARDIN: Right.
DR. STEINDLER: -- applies in the time, within the time of
compliance.
DR. GARRICK: Yes, one of the things that I would be
interested in is if you look at 50 times with respect to seepage and 100
times with respect to unsaturated zone flow, what do you think is a
reasonable goal in each of these cases, because that would certainly
tell you which one you want to put the most emphasis on if all you are
going to get is reduction from 50 times down to 45 times, say on
seepage, and in the case of unsaturated flow you are going to get from
100 times down to 10 times -- then that would certainly suggest where
you ought to put your effort.
Can you say anything about what is a reasonable expectation
here in terms of the uncertainty? Obviously you are not going to
eliminate the uncertainty. You are just going to reduce it.
MR. HARDIN: Right. These are not confidence interval
analyses.
DR. GARRICK: Right.
MR. HARDIN: We ascribe no quantitative designation to the
range.
DR. GARRICK: Yes. One of the things that would really help
this process is kind of what I think Marty was getting to is that if you
could see a PDF of the peak dose before and after and how these programs
are expected to impact that peak dose as a function of these, say, three
major contributors, and I think all the evidence points to that these
are the three major issue, that would be very beneficial.
You would see more graphically what is likely to happen by
addressing the quantification of the dose where by quantification I mean
the curve.
MR. HARDIN: Right. In our December briefings, as you may
recall, Dr. Dockery showed a correlation analysis had been done, a
statistical analysis of the principal factors against peak dose rate
which tended to bolster these conclusions.
DR. GARRICK: Do you have any sense of what is a reasonable
goal with respect to your 50 times and 100 times number within the time
period between now and when you submit --
MR. HARDIN: I hesitate to give you a range, let's say,
tenfold or twentyfold, that would apply to all the factors.
DR. GARRICK: All right.
MR. HARDIN: Because clearly some of the factors are going
to have more intrinsic uncertainty than others.
DR. GARRICK: That's right and that is what I am sort of
getting at is where would it be best for the resources to be allocated
with respect to, say, just these three issues?
MR. HARDIN: And the answer is where it is most desirable
and feasible. That is where we interject judgment as to what we can
achieve programmatically and include in the SR and LA.
DR. HORNBERGER: And of course it is important to keep in
mind that with two of these the issue isn't necessarily finding that
seepage puts us in the lower 10 percent. Your measurements could put us
in the upper 10 percent, near that top 45 to 50, rather than 5 to 10.
DR. GARRICK: Yes, right. That's kind of what I was
struggling with.
If we went from 50 to 49 and 1 and from 100 --
DR. HORNBERGER: But it is still important to know that.
DR. GARRICK: Right, right.
DR. STEINDLER: One other quick point. The implication here
is that you talk about testing to support the seepage model and the same
kind of general set of words are found in all of those --
DR. HORNBERGER: Right.
DR. STEINDLER: -- which boosts your confidence goals. No
place do you seem to address model uncertainties. It seems to me that
in some cases you are not even sure you have a clue as to what the
mechanism is and so the model itself may be pretty far off.
Did you factor this in someplace?
MR. HARDIN: Model uncertainty was certainly used as a
concern in the current confidence goal and in terms of assessing -- I'm
sorry, in the current confidence. In terms of assessing the confidence
goal it would be necessary to extrapolate where we think we could be and
that also has been done, but I understand your concern in that we have
not specified how the models would be changed --
DR. STEINDLER: I don't want to know how the model is going
to be changed. The thing I am trying to find out is whether or not this
confidence goal, you know -- the argument for the confidence goal being
at the level it is seems to be based entirely on the acquisition of data
and does not seem to address something that you are going to do to
enhance confidence that the model uncertainty can be reduced. It is
that difference that I am looking for.
I mean you have great data but your model is lousy so
general extrapolations --
MR. HARDIN: Well, I have given it that sense, and I would
allude to some of our peer reviews which have told us that we don't have
enough data. With more data the models will improve and that is really
what we are saying.
We understand where the models are the thinnest.
DR. STEINDLER: We haven't got enough time to work on that
one. I'll just let it pass.
DR. GARRICK: Well, of course if we get enough data, we can
simplify the model and in the limit we don't need a model if we have
enough data.
DR. FAIRHURST: If you have got the wrong model, the
interpretation of the data will be wrong.
DR. STEINDLER: Exactly. The acquisition of data is
normally driven by some picture that you have called the model. If you
continue down that road you probably aren't going to make a whole lot of
important changes to the model and the model uncertainty remains as an
unresolved issue. That is all I am saying.
DR. GARRICK: Yes. Lynn?
MS. DEERING: I just wanted to add something to this and
this was based on something I heard Abe Van Leuyk say at the NWTRB
meeting, and Ernie, tell me if I have got this wrong.
He was implying with respect to confidence goals if a low
confidence goal is assigned if DOE believes they have already -- there
may be a lot of uncertainty but DOE believes it has captured that
uncertainty in the current model, therefore it is bounded. A high
confidence goal is given to those areas where the modelling is not
expected to change much for the worse. In other words, dose could go
down if they work on refining the model to their advantage, but it is
not -- they are not going to put the money into a model where they feel
the dose isn't going to get worse.
Does that make sense? That is what I heard out there.
MR. HARDIN: I wouldn't say that at all.
We are very keenly concerned with defensibility.
DR. GARRICK: And also the confidence goal only makes sense
if it's rooted in some sort of a measuring process. In other words, if
I have six orders of magnitude of uncertainty in a parameter and it
doesn't affect the dose, I don't care. I don't care if I have six
orders of magnitude of uncertainty, because I'm not concerned about the
science of that particular parameter beyond its impact on the bottom
line.
So that's the only thing that makes any sense as to what the
confidence goal should be is what the ultimate impact is on the
performance measure. And I think we need to be very careful about the
implication that these confidence goals are something that people sit
down and make a judgment. If that judgment reflects performance
analysis and performance measures, then that's okay. But that should be
the driver. And then I hope that's the direction it's going.
DR. HARDIN: Yes.
DR. HORNBERGER: Okay. With that short answer, thank you,
Ernie. We'll take a 15-minute break and reconvene promptly at 10:36.
[Recess.]
DR. HORNBERGER: Okay. We are reconvened, and I think the
schedule has David Stahl doing the next presentation.
No? Well -- that's fine. I wasn't sure. We changed it.
That's fine.
DR. HOXIE: Am I on? I don't hear a voice.
DR. CAMPBELL: You're fine.
DR. HOXIE: Okay. Sorry. I am going to be talking to you
about seepage into drifts.
My name is Dwight Hoxie, and I need to explain the kind of
curious beast that I am. I am an employee of the United States
Geological Survey, but I work within the M&O organization in Las Vegas,
and I am responsible for managing the process modeling program which
includes UZ flow and transport models, saturated zone flow and transport
model, and near field models. And the reason why I'm probably here on
the program is because I was told we need to focus on the planned work
for SR and the license application, and since I act in the capacity of a
manager and planning is one of the things I do, therefore that seems
appropriate.
So what I'm going to be doing is talking about seepage into
drifts, just remind you why this particular issue is of significance,
and that is I think it was Steve Brocoum said earlier today, essentially
that if we did not have any water seeping into the emplacement drifts,
we would have no waste package degradation much to worry about or not as
much anyway, we would have no medium by which to mobilize the
radionuclides from the waste form, and that we'd have no medium to
transport them through the engineered barrier and subsequently into the
unsaturated zone and to the underlying water table. So this is why
seepage is very important.
The work that we have planned actually for the license
application is really a set of ongoing work that is being continued and
will be completed or at least mostly completed by the time of the
license application. And this is essentially a table of contents for my
talk.
I'm going to be talking about the alcove and niche seepage
testing in the main drift of the exploratory studies facility. The
testing that is planned in the east-west cross-drift. I will be talking
about the geochemical and mineralogical work that is going on or will --
is going on actually in cross-drift. I'll talk about moisture
monitoring and talk about update of our seepage and percolation process
models. So let me first talk about what is going on and will be going
on in the main drift.
First of all I think all of you have this. It's not as high
a quality map that I would like of the ESF, this being the ESF located
here, the main drift going essentially north-south, and then with the
cross-drift going across the potential repository block.
I'll be talking about alcoves, specifically alcove number 1,
which is up here by the north portal. I'll be talking briefly about
alcove number 4, which is down on the so-called north ramp. I'll be
talking about alcove number 7, which is located down here at the end.
I'll also be talking about four of the niches that have been excavated
in the ESF. I'll be talking about niche 1 and niche 2, which are very,
very close together. They are located very close to the Sundance Fault,
which is a structural feature.
DR. CAMPBELL: You need your battery changed.
DR. HOXIE: I need my battery changed. Where is the bunny
when you need him.
Okay, is that working?
MR. LARSON: Yes.
DR. HOXIE: I couldn't even tell. All right. Where was I?
Alcove number 7, about the niches, niche 1 and 2, located
near the Sundance Fault, niche 3, which is located where the cross-drift
crosses over the main drift, and I noticed on this slide very
conveniently that niche number 4, which is at station 47 plus 88, which
is about right in here, is not shown on this particular map.
I might also point out that I'll be talking about the
cross-drift. I'm going to be talking about a crossover alcove which is
going to be located where the cross-drift goes over the main drift.
I'll be talking about the crest alcove, which is located beneath the
crest of Yucca Mountain. And also going to be talking about two niches
that are planned to be constructed in the cross-drift, niche 5 and niche
6. Their locations shown on this map unfortunately are incorrect. They
have been revised I learned on Monday, and I'll try to give you that
information as we go along. We have two viewgraphs -- I could just
leave this up, but I'll leave it on the side, anyway, and ask you to
refer to your handout.
Okay. First of all, alcove number 1. I'm going to talk
about what has -- the status of this test today. It really was a
prototype test. Alcove number 1 is located very near the entrance to
the ESF, so the alcove actually is only beneath the surface by about 32
meters. The experiment consisted of applying water on a 91-square-meter
area for 158 days at an average rate of 1.7 centimeters today. So this
was a controlled infiltration experiment with the idea of trying to see
if any water or how much water would ultimately drip into the drift.
And if you multiply everything out, you come out with about 240,000
liters was the total amount of water that was applied during 158 days of
the test.
The modelers, someone was talking about model uncertainty, I
think our models actually are very good because the modelers predicted
that they should see water entering into alcove 1 four hours after
irrigation began at the surface, and they were only off by a little less
than 57 days. So I don't know why anyone is concerned about model
uncertainty.
Anyway, but I think this is actually very important, because
what realization was -- so there. I think what the realization was is
that it takes a certain amount of water to wet up the rock mass
sufficiently to get it to move through. This is a fractured welded
tuff, it's the Tiva Canyon tuff. The fractures are probably filled with
calcites and soils and so forth, and it just takes a long time for the
rock mass to wet up sufficiently to get it to where it percolates down
and then can seep into the drift. And of all the water that was
applied, about 11 percent was recovered in their network of collectors
that was in the drift.
This was a prototype test. The work is continuing. A new
test is actually about to be initiated, and this test is going to be
refined so that they can do a better job of quantifying things. And
what we really want to be able to do is to develop some quantitative
relationships between how much water and at what rate it seeps into the
drift versus the applied infiltration rate at land surface. And the
other thing that they want to be able to do is to do tracer testing so
that they can get breakthrough curves. This will allow them to develop
travel times and also to potentially identify flow pathways within this
fractured rock mass.
DR. FAIRHURST: Could I just ask --
DR. HOXIE: Sure.
DR. FAIRHURST: Your model that was off by 57 minus 4
hours -- but in that, is that a fracture --
DR. HOXIE: Yes, that was a fracture model.
DR. FAIRHURST: It's a discrete fracture model.
DR. HOXIE: Yes, it's actually -- it's what we call
dual-permeability models.
DR. FAIRHURST: Ah, it's not a fracture model.
DR. HOXIE: Okay. So it's a fracture continuum superimposed
on a --
DR. FAIRHURST: It's a fishy fracture.
DR. HOXIE: A matrix continuum.
DR. FAIRHURST: There aren't any -- just is a bit leakier.
DR. HOXIE: All right. Moving to the other end of the SF,
at alcove 7, this is also directly a drift seepage test, but this is
under ambient conditions, and the alcove was constructed to provide
access to the southern Ghost Dance fault. The alcove is about 200
meters below land surface. It's in the Topapah Spring welded unit,
which is our potential host rock for the repository.
The modeling again is estimating based on the infiltration
estimates at land surface that the ambient flux in the vicinity of the
drift should be about two millimeters per year. The drift is bulkheaded
off so that there's no air exchange with the main drift itself, and
actually there are two bulkheaded alcoves, one that encompasses the
fault, one that's outside the fault. And the idea here is simply that
we're just passively monitoring conditions within the drift. We're
measuring the temperature, relative humidity, barometric pressure, and
in the rock mass itself, embedded in the rock mass we have devices to
measure the water potential in order to see if we can get any seepage
events moving down through the rock.
And again back to modeling again, we have not detected any
inflow into this alcove yet, and the models are estimating that it will
be about 10 years before we could anticipate seeing any effects from the
recent El Nino event. So this may be a long wait.
I want to talk about alcove number 4 before I show the
picture. Let me talk about that just -- and then I will show you the
picture for actually almost a different reason.
Alcove number 4, if you look in your figure, it's actually
in the north ramp. It's located in the Paintbrush nonwelded
hydrogeologic unit. This is not directly related to seepage into
drifts, but it's probably very important for potential seepage into
repository drifts because our conceptual model is that the Paintbrush
nonwelded unit tends to mediate flow that is moving downward from land
surface and into the potential repository host rock.
And the mechanism here is that -- our concept is that at
land surface above the repository we have the Tiva Canyon welded unit,
which is highly fractured. The supposition is that net infiltration
from rainfall -- precipitation will enter the fractures, move down
through the fractures. They will then impinge on the nonwelded unit
which is relatively unfractured, has a very high matrix porosity, has a
very high matrix permeability relative to the matrix of the overlying
welded unit and so the flow will tend to transform from
fracture-dominated flow into matrix-dominated flow, which presumably
would tend to homogenize the flow both in space and time.
It would tend to dampen out episodic events and perhaps even
spatially homogenize the flow, so that this would be that in the
underlying Topopah Spring unit, which is the repository host rock,
perhaps the flow would be -- we would have a source of water at the top
that would be more uniformly distributed and the flow therefore would be
more uniform in the Topopah Spring -- again, probably fracture-dominated
but probably with many, many fractures participating rather than just
discrete fractures conveying the bulk volume of the flow.
So far what we have done in this alcove is -- the plan is
actually to do air injection testing to determine the permeability of
the rock mass and we do liquid release testing to see how water moves
through the unit and then we'll monitor the moisture in the rock mass in
boreholes and we will be investigating a complex system involving
faults, fractures and layered heterogeneous units.
I'll just point out that right to date what we have done, we
have taken core samples from this alcove and measured hydrologic
properties. On the core samples we have have done some preliminary air
and liquid release testing to get the hydrologic properties of the rock
mass itself.
Now there is a diagram here. This is looking at the face at
the end of the alcove and all I really want to point out here is that
things are fairly complicated. We have a fault here, we have a fracture
over here that actually may have been mining-induced -- it is not
completely clear. We have different kinds of stratigraphy. Some of
this is pretty clayey material. Some of it has been altered into
Zeolites so we have a heterogeneous rock mass, but the I really want to
make out is that the kind of testing that is being done here is very
similar to the kind of testing that is being done in the niches that I
will be talking about, with the idea being that we will have multiple
boreholes. We will do crosshole tests across these different boreholes.
Some boreholes will just have monitoring instruments in them and then in
many of the cases where we have a niche study where we actually were
trying to determine how water will move down through the rock mass
itself, we have a series of boreholes that overlap that essentially
create a slot along the bottom and where we can collect samples
discretely but distributed in space so that you can do tracer tests or
quantify rates of flow in particular localities.
This is just an example of the kinds of things that are also
going on in the niches, so that when I talk about the niches I want you
to kind of have this picture in your mind. I don't want to go into more
details on this test other than that.
So getting on to the niches, and just to make sure that
everyone is very clear, we have two concepts in our testing complex
within the ESF. We talk about niches and alcoves and just in case you
weren't completely clear, it's just a matter of scale. The axial length
of niches are on the order of 10 meters or less; the axial lengths of
alcoves are on the order of 10s of meters. That is really the only
difference. They are both excavations off of either the Main Drift or
North Ramp or South Ramp or wherever, or the Cross Drift.
So far we are doing seepage testing in Niches 1, 3 and 4.
We have done air injection testing in 3 and 4. All that work has
actually been pretty much completed, and that gives us hydrologic
properties such as permeabilities of the fracture system. This is all
focusing primarily on fracture flow.
Then we will be doing both liquid release, which is just
flux types of measurements, and then tracer testing, and the idea here
is to try to gain some really empirical hard data on, first of all, the
effects of capillarity at the boundaries between the niche and the wall
rock itself, the idea being that at least according to theory if you
have a water front moving down through a porous medium and it encounters
a large opening like a niche or an emplacement drift, capillarity
effects should tend to deflect the water around the drift, and so it is
to test that hypothesis and to how well that works in a fractured
medium.
I tried to determine what seepage threshold fluxes might
be -- that is, the idea being that there must be some minimum flux that
you have to have impinging on a drift in order to induce seepage into
that drift.
Seepage function as a function of the liquid injection flux,
this is probably a poor choice of a word. I probably should just simply
say seepage percentage because seepage fraction has a usage in TSPA that
is different from what I have in mind here. This is simply that, well,
what is the fraction of the water that you impinge on a drift that
actually seeps into the drift, and how is that a function of whatever
that incident flux might be.
One of the big uncertainties within our analyses in this
fractured rock mass is how does the fractures and matrix interact? That
is, how does water exchange between the two? What are the conditions in
which you may have dominant fracture flow or dominant matrix flow? And
we are also going to try to get a handle from all of this testing on
these kinds of effects.
I might just say that we have completed testing at Niche 3,
testing is ongoing at Niche 4 and we will complete the testing in Niche
1.
All right. Now I want to talk about the work that we are
planning to do in the Cross Drift. One of the first and perhaps most
relevant to a seepage issue is the experiment that we plan at
essentially the junction in plan view anyway of the Cross Drift with the
Main Drift of the ESF. What we want to do is to construct an alcove
above, essentially above Niche 3, which is in the Main Drift and about
15 meters below the cross draft, and conduct an infiltration test,
presumably very similar to what was done at Alcove Number 1.
We would apply water in the Cross Drift and monitor the flow
into Niche 3 as a function of the amount of water that was applied.
Again we want to try to look at how the flow might be diverted around
the niche as a consequence of the capillarity, and again quantify the
seepage percentage anyway of the incident flux that might seep into
Niche Number 3.
We have, and I have already mentioned this, we have already
completed testing there, so we have the hydrologic properties pretty
well in hand. I might mention also that concurrent with all of the
testing or actually in advance of the testing modeling is being done
based on the measured hydrologic properties in order to predict the
results of the test and try to gain some validation of our modeling
capability.
The East-West Cross Drift Crest Alcove is located beneath
the crest of Yucca Mountain, which is a region that is predicted by the
infiltration modelers to be a region of expected high net infiltration,
probably on the order of 10 to 12 millimeters per year versus an average
of, as Steve pointed out this morning, of six to seven over the entire
repository area. But this is going to be a test that will be very
similar to the one that is going on in Alcove Number 7. The alcove will
bulkheaded off and we will do passive monitoring within the alcove to
see if we detect any inflow as a result of ambient infiltration through
the mountain.
We also plan to do tests in two niches that are going to be
excavated from the Cross Drift. This is going to be very similar to the
kinds of testing that we have been doing in the Main Drift. Actually
this slide is a little bit of a misnomer. I learned on Monday that the
locations of the two proposed Cross Drift niches have been changed, so
that actually we can go down to this bullet now and say that Niche 5 and
Niche 6 both will be located in rock units that previously had not been
tested from the Main Drift.
These will be in what is known as the lower lithophysal unit
of the Topopah Spring and the lower non-lithophysal unit of the Topopah
Spring. These are both potential host rock subunits that were not
penetrated by the Main Drift or at least they were not penetrated
sufficiently that any testing was done, so that is the purposes of the
testing in the two niches in the Cross Drift.
I'll talk about geochemical and mineralogical sampling that
is actually ongoing within the Cross Drift, although I don't have any
results to report at this point in time.
From a geochemical point of view, there is systematic
sampling of samples to extract pore-water chloride concentrations. The
importance here is that if flow through the mountain is dominantly
vertical, then the total chloride, pore-water chloride at any particular
location should be inversely proportional to the infiltration rate at
land surface above that location, so we can test that particular
hypothesis.
And perhaps of more spectacular interest is looking at the
ratios of chlorine-36 to total chloride. And we will be doing this both
systematically along the drift, and also at particular features,
specifically, for example, the Sundance Fault, where, in the main drift
anyway, the Sundance Fault is implicated in an occurrence of so-called
bomb-pulse chlorine-36, which, as everybody probably well recognizes,
indicates a potential fast pathway for which water had flown from land
surface within the past 50 years or so.
But there is more to chlorine-36 to total chloride than just
bomb-pulse. Actually, the ratio gives us an idea of groundwater
residence time. And just for example, the background chlorine-36 to
total chloride right now stands at about 500 times 10 to the minus 15,
and it is a dimensional-less number, of course. But if the number is
much, much less than 500 times 10 to the minus 15th, that indicates a
groundwater residence time probably on the order of the half-life of
chlorine-36, which is 300,000 years. So that gives us some idea that we
would have a very old residence time.
Bomb-pulse chlorine-36, of course, would indicate a fast
pathway, something where water has been transmitted through the usee
down to the collection site within the past 50 years or so. But
chlorine-36, it is also now well documented, the ratio -- there was an
increase in production of chlorine-36 apparently relative to modern day
about 10,000 years ago, so that if we have chloride-36 -- chlorine-36 to
chloride ratios in the order of 500 to 1,000 times 10 to the minus 15th,
then that indicates water that perhaps is on the order of 10 to 20,000
years old. So it gives us a bit of a handle on flowpaths and residence
time within the unsaturated zone.
The mineralogic sampling that is planned is very similar to
what was done in the main drift. We are particularly going to be
looking at the occurrences of secondary hydrogenic minerals, primarily
calcite and opal that predominantly occur in the fractures and fault
zones. After collecting the samples, we analyzed them using various
techniques, carbon-14, thorium to uranium, uranium-lead, to measure
ages. And when you are measuring the ages, I remind that you that this
is done with very, very microscopic samples and so that you can measure
the outer layers of a small crystal and measure the interior layers,
and, therefore, get a sequence of ages and an idea of the rate of
deposition of the particular mineral. So that is why this is very
important.
And of course, if you have some idea of the deposition rate,
and have -- apply some chemical principles, you can infer back estimates
of rates of flow through the UZ. And based on this, from the work in
the ESF, people are talking about an average over several millions of
years of something like 2 millimeters per year moving down through the
fracture pathways.
We also look at the stable and radiochemical isotopes.
Oxygen fractionation, we look at so-called delta-18, which is
essentially a difference between 018 and 016, and what this tell us is
that if this -- this ratio is actually a function of depth through the
UZ, and it tells us something about how oxygen is being fractionated
along the flow pathways. And, by the way, these measurements are on
calcite samples, so it is telling us something about the calcite
deposition.
Carbon-13 tells us something about the soil gas composition
from which the biocarbonate originated that ultimately led to the
calcite deposition at depth within the UZ. Strontium-87 is a --
strontium is an element that does not actively react strongly with the
welded tuffs like the Catiba Canyon, but it does interact, presumably,
with the non-welded tuffs. And so if this particular ratio changes with
depths, and it does actually make quite a change as it goes across the
PTN on welded unit, then this is telling us something about the reaction
chemistry along the flow pathway.
We also look at the initial uranium-234 to 238 ratios. If
you have a very, very long period of time, these ratios ought to be one
because you will have -- uranium-234 is a daughter product of
uranium-238, so they should come into equilibrium. The fact that we
don't have ratios that are equal to one everywhere tells us that there
is something happening preferentially is causing that ratio to change
along the water pathway. And the way it in which it is changing in the
UZ has been interpreted to indicate something about waterflow volumes
and flowpath lengths.
We have low, we have small waterflow volumes, and long
flowpath lengths, and this is taken to support the concept, anyway, that
water in the UZ, particularly in the repository host rock, is widely
spread out among multiple fractures and perhaps even moving as film
flow. That does not discount, of course, that we might not have
episodic events such as those that would lead to bring chlorine-36,
bomb-pulse chlorine-36 into the drift.
Okay. I want to talk about moisture monitoring that is
going on in the main drift and in the cross-drift. This has been a
long, ongoing program. We are measuring temperature, relative humidity
and wind speed at a number of stations within the ESF, and I think
everybody understands the station nomenclature, the 7 plus 40 means 740
meters, from -- in the ESF, from the North Portal. And this is all
being done at a sampling every 15 minutes. And the idea here is because
we are ventilating in the main drift, we want to get some idea of how
much moisture actually is being carried out with the ventilation system.
And we also have monitoring stations at Alcoves 1 and 5 and at Niches 1
and 2.
I think more interesting is the work that's going on in the
cross drift itself. We do the same kind of thing to look at what the
effects of ventilation there are, so again we have stations where we
measure temperature, relative humidity, and wind speed. But to me what
is more interesting is that we have a heat-dissipation probe, which is a
device to measure water potential in the wall rock. We have one
installed every 25 meters from station 0 plus 50 in the cross drift and
station 0 for the cross drift is at the intersection with the ESF at the
North Ramp, at 25 meter intervals all the way up to Station 25 plus 25.
And we're sampling these every four hours.
In addition, every 50 meters we have a neutron bore hole,
and these extend from Station 50 to Station 25, and we go out and log
these bore holes for water content in the wall rock every two months.
And both of these holes, the bore holes that are involved, are all two
meters deep. So we're relatively well into the rock mass and away from
the perturbing effects of the drift itself.
And what I think is very, very interesting is that -- I will
pass this on -- is that the data that is coming out from these water
potential measurements is that the rock mass two meters in from the
cross drift is actually quite wet. The potential is about minus .8
bars, and the saturation of the rock mass is about 90 percent. And this
is considerably wetter than was found to be the case in the main drift,
but in that case we were not able to put probes back more than 50
centimeters from the wall rock itself, from the interface with the
drift, and probably therefore we got much, much drier conditions
probably as a result of rock dryout from the ventilation system in the
drift.
So anyway we have a report, a predictive report that was
developed about a year ago for what we thought conditions would be in
the cross drift, and at least with the water potential we're finding
that they're a lot wetter than we had predicted based on extrapolation
from --
DR. HORNBERGER: Dwight, we have an awful lot of material to
get through.
DR. HOXIE: Yes. Okay.
DR. HORNBERGER: Perhaps you could speed it up and hit the
highlights.
DR. HOXIE: I will.
Okay. I just wanted to mention something about what we're
doing about the modeling program. Our basic drift model right now
simulates a five-meter drift in a block that's 50 meters long, 35 meters
tall, and 43 meters wide. The grid spacing is .5 meters, and we
generate fracture permeability fields, this is a fracture-based model
based on map fracture density and permeability test data from the main
drift. And the whole idea here is to -- oh, we used the site scale flow
model to provide input fluxes as a boundary condition and try to predict
using the model what the seepage into a drift would be.
We are going to refine and calibrate the model with respect
to all of the available drift and alcove test data. The model right now
has a circular drift. We're going to alter the geometry to try to
simulate the effect of drift collapse and we're going to try to by using
finer grids look at things like the effects of wall rock surface
roughness and potential film flow around the drift.
We also need to allow for the near-field effects of
repository heat that could alter the rock mass itself and change the
water chemistry of water entering the drift. With the case of our 3D
site scale, mountain scale model, I'll talk about that in the next
presentation, but we're refining the grid for better spatial resolution
for infiltration, calibrate the model. We're going to use simulated --
simulate the chloride transport, chlorine-36 transport, carbon-14
transport as a means to calibrate the model to better predict fluxes
through the mountain.
And just in summary of this talk, we have our testing
program in niches and alcoves, we have work planned for the cross drift,
and we are going to take all of this data and try to incorporate it and
to improve our models, both their numerical capability and their
conceptual basis.
So that concludes that talk.
DR. HORNBERGER: Okay. Thank you.
Okay. Questions.
DR. FAIRHURST: Yes. On one of your slides for one of the
niches you said this fracture may be mining-induced. You weren't sure.
As a general question, how do you take into account the consequences --
I mean, how do you create these niches? By blasting?
DR. HOXIE: Let's see. That -- actually the one in the PTN
was excavated using an alpine miner. So it's clutching.
Oh, when I say that fracture was induced, it was probably a
desiccation fracture. This was nonwelded tuff. It was damp when they
excavated it. And it's probably dried out. So that's one.
DR. FAIRHURST: But there is a potential, I presume, for you
to disturb fractures and change their aperture and things like this
and -- all your measurements in the excavation damage zone. And yet it
seems to me that you don't have any technique. There are techniques
available to determine whether you disturb the rock mass during the
process of making the niche.
DR. HOXIE: Right.
DR. FAIRHURST: I just wonder if somebody, evil-minded
individual may throw a doubt on --
DR. HOXIE: Okay. What is done --
DR. FAIRHURST: Everything else.
DR. HOXIE: Right. What has been done with the niches in
particular is that the first thing they do is drill bore holes, do
testing in the bore holes, excavate the niche, do more testing, and then
try to determine what the effects of mining the niche was on the result.
So they do try to take that into account.
DR. FAIRHURST: But do you do any attempt to do acoustic
emission work in bore holes to see the sources of any movement?
DR. HOXIE: I can't answer that question. I don't have that
information. But I'm not sure, they may well do. I don't know.
DR. HORNBERGER: Ray.
DR. WYMER: I was just curious as to -- you're getting a lot
of useful information here about how things move through the rock. I
wondered to what extent this information will be applied to what happens
in the unsaturated zone.
DR. HOXIE: In what sense?
DR. WYMER: In the sense that you also have water moving
through the unsaturated zone.
DR. HOXIE: Right. Well, we are talking about the
unsaturated --
DR. WYMER: I thought you were talking about seepage into
the drift.
DR. HOXIE: We're talking -- ah, this is seepage from above.
DR. WYMER: Yes.
DR. HOXIE: Coming down -- all the drifts are in the UZ, so
this would be seepage --
DR. WYMER: So whatever you get you will apply --
DR. HOXIE: Right.
DR. WYMER: Across the board.
DR. HOXIE: Yes.
DR. WYMER: Yes. Yes, when I read seepage, I usually think
of what's coming down rather than what's going out the bottom.
DR. HOXIE: Okay. Well, that's what I'm talking about. I'm
talking about seepage water that's coming down through the UZ, impinging
at the drift, and then dripping into the drift.
DR. WYMER: Okay.
DR. HOXIE: Okay. That's what I mean by seepage.
DR. WYMER: Yes. The word "seepage" had a different
connotation for me. Okay.
DR. FAIRHURST: Looking into transferring this into the SPA
model, that model will be looking at seepage into drifts that have
undergone a thermal cycle, have cooled back down again. So around them
will be a significant large damage zone. So you won't be having seepage
directly -- I had an offline conversation with Ernie. He was saying you
may consider that as essentially backfill. So do you have a model which
shows seepage into a "filled" region with a hole in the middle of it?
DR. HOXIE: I don't think we've actually done any so-called
backfill modeling at the present time.
DR. FAIRHURST: It's sort of pseudo backfill.
DR. HOXIE: Pseudo backfill. I see what you're saying.
DR. FAIRHURST: Broken rubble is sitting there and inside of
it you've got an open drift.
DR. HOXIE: Right. But I think this is something that
could -- this is an extension that could be done with our current
seepage modeling.
DR. FAIRHURST: I was just wondering why the reverse isn't
the case. You look at what the problems are from a model and then see
what tests to do to validate or invalidate the model. At any rate, it's
easier to criticize, I know, than do it.
DR. HORNBERGER: I'd like to explore that just a little
farther. It's pretty clear that the seepage model is -- you are going
to have to rely on that, not just because that's what PA does, but
because your tests are all done in very wet conditions because you need
to make the measurements now.
DR. HOXIE: Right.
DR. HORNBERGER: Whereas the seepage that you really want to
calculate is at the dry end, and if you don't have the physics right,
then that extrapolation from wet to dry may not hold water.
[Laughter.]
DR. FAIRHURST: So to speak.
DR. HORNBERGER: I'm curious about what you're doing in
terms of evaluating the physical models. As I understand it, you're
just using -- you're using an ECM. Do you have any intention to
investigate discrete fracture models?
DR. HOXIE: Actually I think they are using discrete
fracture models to simulate in advance of the tests especially for the
niches, because that's such a small scale. And where they can go in and
they can map the fractures so they can try to put in discrete fractures,
and this is what they've been doing for prediction. But of course we
can't -- this is not really feasible, certainly not at the mountain
scale, and it may not even really be feasible at an emplacement drift
scale where we're having to deal with hundreds and hundreds of
fractures.
So I think that it's probably a scale problem more than
anything else, and I think our expectation is that we have sufficient
fracture density within the Topopah Spring that one can justify using a
fracture continuum kind of model. And I think there is some basis for
that, because the models that are being generated with the stochastic
permeability fields are based on air permeability data, which shows a
wide range, indicating that you, you know, in the test you're
intercepting in some cases many fractures, some cases a few fractures,
and so that gives you statistical distribution of permeability. And I
think by applying that, then I think you've got some basis on which to
proceed. Also, I think that we're going to gain an awful lot of
information just from all the niche and alcove studies that are going
on.
At least we'll better constrain our conceptual model for how seepage
might occur.
DR. FAIRHURST: Following that up again a little bit, and I
-- please don't misunderstand this as being smart-alecky because it is
an extremely difficult problem. But in the STREPA studies, they looked
at fractures and you go and map the fractures and there's 150, 200
fractures. None of them look any different than the rest, but 90
percent of the water comes out of ten of the fractures or five or one of
the fractures. How do we -- we're talking about seepage onto a canister
here and the rates of seepage. It's a nasty problem. I just wonder how
-- maybe you're just going to do it statistically and say --
DR. HOXIE: That's the current approach, and we also have to
discriminate between, you know, some fractures that are -- or fracture
networks that are locally more conductive than, say, the overall
fracture mass itself. I mean, it does get very, very complicated, and
our niche studies are showing just this kind of phenomenon. So --
DR. FAIRHURST: If you get a seismic event from that, you
stop someplace and start up somewhere else.
DR. HOXIE: I think that's very possible.
DR. HORNBERGER: What -- I mean, you started out your
presentation with, you know, your observation 57 days versus four hours.
How have the models done with regard to your other tests as the data are
coming in?
DR. HOXIE: I'm sorry, I don't have any information on that.
I really don't. I just read a 1998 report, but they didn't discuss the
results of the modelling.
DR. HORNBERGER: Okay.
DR. HOXIE: And I think probably because the tests are still
going, so that they don't have results yet that they want to quote.
DR. HORNBERGER: Right. And I understand that there has
been some criticism of the boundary conditions used in your modelling.
Have you considered changes that you might do in the modelling with
regard to again exploring different boundary conditions as well?
DR. HOXIE: I --
DR. HORNBERGER: You don't know that. Okay.
DR. HOXIE: I don't know which boundary conditions --
DR. HORNBERGER: Okay.
DR. HOXIE: -- that you're referring to.
DR. HORNBERGER: Okay.
DR. HOXIE: I mean, in our drift seepage modelling, what we
normally do -- well, if you're doing a test, you use the flux that
you're going to impose in the test, and in the case of ambient seepage
into a drift, we usually use the output from the UZ site scale model as
the input flux or some multiple thereof if we want to indicate, you
know, or simulate a higher infiltration event, like a climate change.
So I would be happy to answer your question if I knew which
boundaries you're talking about.
DR. HORNBERGER: I understand.
Other questions?
DR. GARRICK: Amazingly I don't have any.
DR. HORNBERGER: Okay.
DR. HOXIE: You may have another opportunity.
DR. HORNBERGER: Okay. And Dwight, I'll give you the same
heads up.
DR. HOXIE: I will try to go this one. I will abandon the
-- I'm going to talk about our site scale flow and transport. I'll try
to make this as brief as I possibly can.
What we're really concerned about is the capability of the
UZ to reduce concentrations of radionuclides beneath the potential
repository. We need to be able to, in doing that, that being our
concern, is to look at those kinds of processes that are involved, like
adsorption, dispersive mixing with other waters, matrix diffusion --
that is, moving radionuclides out of fractures into the rock matrix --
and also allowing for colloidal facilitated transport.
I just have three things to talk about: the experimental
evaluation that's going on, our use of natural analogs and manmade
analogs, and our mountain scale model. So hopefully this will go very
quickly.
In terms of experimental evaluation, we have the work at
Busted Butte, we have the work that I just talked about in the ESF --
that certainly all folds into this -- plus we have laboratory studies,
both of colloids and radionuclides.
In Busted Butte, the test is off the repository block, of
course, as you all well know. The phase 1 testing was completed in
January.
The major conclusions. This is a test in a non-welded tuff.
It's a tuff that occurs below the potential repository, so it is germane
to radionuclide transport.
Within the vitric part, so-called vitric part of the Calico
Hills, matrix flow is completely dominant. This accords with our
conceptual model in this kind of rock.
When fracture flow does occur, when it's induced to occur
within the non-welded tuffs, the rate of flow is limited by the ability
of the water to imbibe back into the rock matrix, and so that fracture
flow doesn't -- is generally not sustained unless we have essentially
full saturation of the surrounding rock mass. And we also discovered
that yes, heterogeneity can deflect flow.
Busted Butte, which we're now going into phase 2, which I
don't know what the schedule is for that, but certainly within the
licensing time frame, and this is actually now going to be a test, a
similar test that was done in phase 1, but this time would be looking at
the contact between the Topopah Spring welded unit and the upper part of
the Calico Hills.
The other aspect of the testing that will be done, of
course, is to complete the analyses that -- of the phase 1 test results.
In terms of ESF field test, I think I have already talked
about that in the previous talk, so I won't really say anything more
except that there is an Alcove 6, which is also on the Ghost Dance
fault, that is actually going to be dedicated -- tests are going to be
conducted dedicated to looking at this issue of fracture matrix
interaction and trying to quantify that more substantially.
In terms of laboratory data, we're doing quite a bit of work
at LANL looking at colloids, both those that are generated from the
waste and also looking at the development of colloids within the far
field, near field of the potential repository that would develop
naturally within the system, and the stability of these colloids and the
rates at which radionuclides might particulate plutonium, might adhere
or adsorb and desorb from them.
In terms of other laboratory work, this is probably not so
much laboratory, but we're updating our databases for the solubility
ranges of those radionuclides that are of particular concern to TSPA,
and we're also doing laboratory solubility measurements on neptunium and
technetium under higher pHes and reducing conditions to extend the
database.
Talk briefly about analogs and how those are being
implemented. The Yucca Mountain project has a long history of
participating in various degrees of -- in numerous natural analog kinds
of studies, but the problem has been most of these that have been done
have been done in saturated zone environments. We need really to be
looking at unsaturated zone environments if we're looking at analogs for
the repository. Just to -- and so we have had an on again, off again
program. It's on again now. We had a workshop in July, another
workshop in February, and I understand there is an Appendix 7
interaction scheduled for March.
Particularly for the UZ and SZ as well, but what we're doing
is that we're going to generate synthesis report to develop a strategy
for how to use natural analogs, both for the LA and probably more
relevant to performance confirmation. We're talking about going back to
look at a site in Pena Blanca in Mexico, to get some idea on uranium
transport and the idea of using the analogs from Hanford and Nevada test
site, the Idaho Laboratory to test and perhaps even somewhat validate
our models.
Talk about the status and what we plan to do with UZ site
scale, flow and transport model. The planned work right now is that
there is a new edition of our so-called geologic framework model. It
says planned work; actually, that has now been incorporated. What I'm
talking about here is actually a status since the viability assessment.
So this is work that has been done since TSPA-VA.
We have included, instead of treating faults as just
vertical offsets, we now allow them to be inclined. We have extended
our calibration methodology to allow for two-dimensional so-called model
inversions, which is a parameter estimation technique that calibrates
the model. We have developed a sub-model for the paintbrush non-welded
unit itself that can be used for the Alcove 4 testing as well as for
testing our hypothesis of how water moves through that non-welded unit.
We have also developed a sub-model for the Calico Hills
hydrogeologic unit in which we can incorporate the Busted Butte data as
it becomes available. We can look at the spacial variability of zeolite
abundance and how it affects, for example, the occurrence of
perched-water bodies or transport properties through the UZ beneath the
potential repository. And we're using reactive chemistry modeling
capability to try to incorporate or allow for -- approximate the effects
of repository in heat-induced changes in the rock mass itself.
In terms of work that is going to be done, it is underway,
is that we're going to refine the model grid so that it better matches
the grid that was used for resolving the net infiltration distribution
over the top of the mountain. Again, we're going to go through an
extensive process of model calibration to improve the data, and we will
be incorporating virtually all of the data that becomes available from
the ESF, Cross Drift and Busted Butte.
We will be incorporating data from the mineralogic and
petrologic data from boreholes WT-24 and SD-6 that are not in the
mineralogy models currently, and we're developing a reactive chemistry
module that, in the far field, will be able to look at durable changes
in the rock mass that might be induced by repository heat and chemical
affects.
We are going to be developing and implementing a fully
coupled flow and advective/dispersive radionuclide transport model or
module essentially within the UZ flow and transport model that will be
able to use to compare against the particle tracking methodology that
TSPA currently is using and hope to better corroborate that technique.
And we're also developing a module that addresses colloidal-facilitated
transport through the unsaturated zone for use by TSPA. So this is a
summary of this talk, and so we have field tests, laboratory tests,
natural analogs, and we're trying to improve our overall site scale
model.
And that concludes that talk.
DR. HORNBERGER: Good. Thank you, Dwight. Questions on UZ?
I have, first of all, an overall question. What is the estimate -- what
is your estimate for, let's say, an average travel time of water from
the repository horizon to the groundwater table.
DR. HOXIE: Average, it depends on -- it depends on the
conceptual model, really. And I think --
DR. HORNBERGER: Okay. Give me a range.
DR. HOXIE: I will give you a range. Okay. They can
probably be anywhere from ten years to a thousand years.
DR. HORNBERGER: Okay.
DR. HOXIE: And it really depends on how big a role the
fractures play versus the matrix.
DR. HORNBERGER: Okay. And are both -- are the full range
of estimates consistent with such things as carbon-14 age dates?
DR. HOXIE: I think they are.
DR. HORNBERGER: Okay.
DR. HOXIE: And even chlorine-36, so I think that -- I think
that the real issue is, is that, for example, with the chlorine-36, we
know we have fast pathways.
DR. HORNBERGER: Right.
DR. HOXIE: The question is, do these fast pathways also --
are they capable of carrying significant quantities of water? And that
is the big issue.
DR. HORNBERGER: Right. And, so, is the work that you just
outlined in this talk going to be reduce your uncertainties in that
exact question?
DR. HOXIE: I think what is actually happening is probably
the Busted Butte work is going to enable us to do that. I am hoping.
DR. HORNBERGER: And does the unsaturated zone model allow
you to simulate the fast pathways?
DR. HOXIE: We have what we call a WEEPS model. Yes, it
does.
DR. HORNBERGER: So the WEEPS model will do that?
DR. HOXIE: Essentially, but we can do that. Okay.
Probably the big, critical factor here is, and you are probably aware of
this, is what TSPA calls their fracture and matrix coupling factor, and
this is the idea that you can have water moving down a fracture, okay,
it doesn't interact with the matrix, and so there is no coupling. Or
you can have it such that the water is moving through the fracture, it
is completely in equilibrium with the matrix, in which you have full
coupling.
And so it is this number which people generally say ranges
from zero to one. And it probably depends on your fracture system and
so on and so forth, but it is that quantity that I think may come out of
some of the niche studies, the Alcove 6 study, and the Busted Butte
work, that we might be able to bracket that kind of number. I have got
my fingers crossed. Because you have got a number that goes from zero
to one, and it has immense consequences. When that is zero, then all
your water -- then you have a WEEPS model.
DR. HORNBERGER: Right. Then you have a WEEPS model. And,
again, my recollection, in reading some of the technical basis
documents, unless I misread something, when I looked at the particle
tracking, some of those figures showed transport times where 30 percent
of the material was arriving at the water table in less than a year.
Did I misread those figures?
DR. HOXIE: Probably not, because some of those, with the
WEEPS concept, you end up with a lot of water going down something like
Ghost Dance Fault, which becomes then a major conduit.
DR. HORNBERGER: And would that be consistent with the
carbon-14 and the chlorine-36 data?
DR. HOXIE: I would probably say that it is, because I think
you probably have a range.
DR. HORNBERGER: Okay. So you really to extend the range
you gave me to begin with all the way down to one year, one year to a
thousand years.
DR. HOXIE: I am not sure about the one year, okay. Maybe
some of the TSPA went for a year, but I would have a hard time with
that, mostly because of the 57 days versus four hour predictions. So,
one year sounds awfully fast.
DR. HORNBERGER: Okay. Thank you.
DR. FAIRHURST: But what percentage of the total flux --
DR. HORNBERGER: About 30 percent, if I am not mistaken.
DR. GARRICK: I just wanted to ask, what is the process of
getting the results of your work into the model, into the performance
assessment? And is that done continuously or is it done --
DR. HOXIE: Well, it is probably done in stages, but, for
example, right now, in April, the UZ flow and transport model has a --
has to have the capability of generating the flow fields for TSPA. That
will be used for TSPA SR Rev. 0, as it is being called, the base case.
And then, the way that this would work is that the simulations that are
actually performed are done by a team composed of TSPA modelers and our
site UZ modelers. So that is the interaction that takes place.
DR. GARRICK: Given the uncertainties that seem to be --
exist, and that you are probably not going to be able to do a great deal
about, do you have any sense of what the impact is going to be on the
performance assessment?
DR. HOXIE: Impact in what --
DR. GARRICK: In terms of the performance measures, the dose
calculations, for example.
DR. HOXIE: Well, I think with the information that we have
right now, and probably will be going into SR Rev. 0, we are probably
going to be about the same as where we were TSPA VA.
DR. GARRICK: Yeah.
DR. HOXIE: I don't think that we have anything
earth-shakingly new.
DR. GARRICK: So it is more of a verification.
DR. HOXIE: It is more of a verification, I really think,
that we are doing right now. Now, the only thing I might argue is that
I think -- that is optimistic, is that maybe we are discovering that it
really does take quite a bit of water moving down to impinge on a drift
in order to seep into a drift. We may -- this capillary deflection may
actually be a more dominant mode than we might have first anticipated.
DR. GARRICK: So it seems that where we are headed is that
seepage is going to be there, water is going to be there. What is
different about it is the rate, the flux, and the timing, and what it
means is that if it doesn't get there as soon as is now being analyzed,
that the peak doses will probably be pushed out further in time?
DR. HOXIE: Be pushed out further. That's all, right.
DR. GARRICK: And the uncertainties will increase --
DR. HOXIE: Yeah.
DR. GARRICK: -- as a function of that time. And, so, one
would have to conclude from this, it seems, that the emphasis ought to
be on doing whatever can be done to keep that seepage from getting into
the fuel assemblies.
DR. HOXIE: And I think that is the current strategy.
DR. HORNBERGER: Charles.
DR. FAIRHURST: You were saying that you thought the Busted
Butte studies would be the thing that will give you some help. And I
keep coming back to this question, is the excavations of the Busted
Butte, you know, alcoves, has that -- have you got any indications
whether that will attract flow or divert it, or whether it will, you
know -- is your result going to be -- are you fairly confident that it
has, if you like, been inserted into this regime without influencing it
locally?
DR. HOXIE: I don't know that, from the Busted Butte data,
that we have kind of information. Of course, we conduct the test and we
perturb everything from the background.
DR. FAIRHURST: Yeah, but if you, for example, were to say,
you have got -- the side of the hill, you have got in situ stress
conditions.
DR. HOXIE: Right.
DR. FAIRHURST: Now, you put something in there --
DR. HOXIE: Oh, okay.
DR. FAIRHURST: -- to see whether you are creating tensions
which will open the fractures over a region, which means you effectively
have got a larger region.
DR. HOXIE: Right.
DR. FAIRHURST: Or you may actually do the opposite, you may
increase the compression, which will push it away. And it is something
you could do from a model to say how much of a -- because flow is going
to be pretty dependent on an aperture, isn't it?
DR. HOXIE: See, I don't think those mechanical things have
really been examined in detail.
DR. FAIRHURST: Oh, okay. It is jut an indication of the
uncertainty.
DR. HORNBERGER: Okay. Thanks very much, Dwight.
DR. HOXIE: Thank you.
DR. HORNBERGER: We are going to go on to the engineering
material where there are, essentially, no uncertainties relative to -- I
mean corrosion over 100,000 years.
DR. FAIRHURST: Not in the next 20 years.
Technical work plans that Dr. Stahl will address include
long-term corrosion, continuation of long-term testing of nickel-based
and titanium-based alloys and multiple material interactions such as
tuff against CRM.
In addition, there are models -- predictive models,
mechanistic models being developed for localized corrosion and phased
segregation effects, and these will be supported to the extent
practicable by measurements and observations.
Passivation effects are being measured and testing will
continue to evaluate microbially-induced corrosion which I understand
has not yet been observed on the Alloy-22 CRM material.
That is all I have. After any questions you may have for
me, I will turn it over to subject matter experts in these two areas.
DR. HORNBERGER: Okay. My suggestion is going to be that
after we ask Ernie questions we take our break now It's a natural place
to break -- and then come back and hear the three technical
presentations and keeping in mind that we are going to hear more
technical detail on the three items that Ernie outlined, I would suggest
that any real detailed technical questions we have would be better left
for a little later.
With that caution, I invite questions.
DR. FAIRHURST: Let me ask this one quickly. Ernie, are you
going to be here later?
MR. HARDIN: Yes.
DR. FAIRHURST: Okay. Then we can ask questions -- we can
bring Ernie back on the stand?
DR. HORNBERGER: We can bring him back, yes.
DR. FAIRHURST: Yesterday people from DOE had to leave.
DR. HORNBERGER: Yes. Marty?
DR. STEINDLER: When you say fifty-fold variation in dose
rate, you are talking peak dose rate?
MR. HARDIN: Yes.
DR. STEINDLER: You don't say anything about what the shape
of that curve looks like in the first, say, 10,000 years where the
period of compliance ends.
MR. HARDIN: Right. There was --
DR. STEINDLER: Did you pay no attention to that? Is that
not a part of the driving force for your prioritization process?
MR. HARDIN: Well, let me just say upfront that generally
the dose rates associated with the first 10,000 years of the performance
period are much lower than the peak dose rates -- as I am sure you have
seen from some of our products.
DR. STEINDLER: Yes.
MR. HARDIN: And that -- but there was a strong, there was
considerable attention given to peak dose rates over a million years in
this prioritization process.
We did, in exercising the TSPA models, we parsed out when --
that being zero to 10,000, 10,000 to 100,000, or up to a million -- when
the peak dose rate was calculated to occur.
DR. HORNBERGER: And you also, when you parsed that, as I
recall, you indicated -- you broke down where the processes were
important in giving that dose and my recollection is that these three
turn out to be important in the zero to 10,000 year period as well as at
the peak dose, is that correct?
MR. HARDIN: Yes, that is.
DR. STEINDLER: What I am trying to find out is whether that
startling factor of 100 or factor of 50 or whatever --
MR. HARDIN: Right.
DR. STEINDLER: -- applies in the time, within the time of
compliance.
DR. GARRICK: Yes, one of the things that I would be
interested in is if you look at 50 times with respect to seepage and 100
times with respect to unsaturated zone flow, what do you think is a
reasonable goal in each of these cases, because that would certainly
tell you which one you want to put the most emphasis on if all you are
going to get is reduction from 50 times down to 45 times, say on
seepage, and in the case of unsaturated flow you are going to get from
100 times down to 10 times -- then that would certainly suggest where
you ought to put your effort.
Can you say anything about what is a reasonable expectation
here in terms of the uncertainty? Obviously you are not going to
eliminate the uncertainty. You are just going to reduce it.
MR. HARDIN: Right. These are not confidence interval
analyses.
DR. GARRICK: Right.
MR. HARDIN: We ascribe no quantitative designation to the
range.
DR. GARRICK: Yes. One of the things that would really help
this process is kind of what I think Marty was getting to is that if you
could see a PDF of the peak dose before and after and how these programs
are expected to impact that peak dose as a function of these, say, three
major contributors, and I think all the evidence points to that these
are the three major issue, that would be very beneficial.
You would see more graphically what is likely to happen by
addressing the quantification of the dose where by quantification I mean
the curve.
MR. HARDIN: Right. In our December briefings, as you may
recall, Dr. Dockery showed a correlation analysis had been done, a
statistical analysis of the principal factors against peak dose rate
which tended to bolster these conclusions.
DR. GARRICK: Do you have any sense of what is a reasonable
goal with respect to your 50 times and 100 times number within the time
period between now and when you submit --
MR. HARDIN: I hesitate to give you a range, let's say,
tenfold or twentyfold, that would apply to all the factors.
DR. GARRICK: All right.
MR. HARDIN: Because clearly some of the factors are going
to have more intrinsic uncertainty than others.
DR. GARRICK: That's right and that is what I am sort of
getting at is where would it be best for the resources to be allocated
with respect to, say, just these three issues?
MR. HARDIN: And the answer is where it is most desirable
and feasible. That is where we interject judgment as to what we can
achieve programmatically and include in the SR and LA.
DR. HORNBERGER: And of course it is important to keep in
mind that with two of these the issue isn't necessarily finding that
seepage puts us in the lower 10 percent. Your measurements could put us
in the upper 10 percent, near that top 45 to 50, rather than 5 to 10.
DR. GARRICK: Yes, right. That's kind of what I was
struggling with.
If we went from 50 to 49 and 1 and from 100 --
DR. HORNBERGER: But it is still important to know that.
DR. GARRICK: Right, right.
DR. STEINDLER: One other quick point. The implication here
is that you talk about testing to support the seepage model and the same
kind of general set of words are found in all of those --
DR. HORNBERGER: Right.
DR. STEINDLER: -- which boosts your confidence goals. No
place do you seem to address model uncertainties. It seems to me that
in some cases you are not even sure you have a clue as to what the
mechanism is and so the model itself may be pretty far off.
Did you factor this in someplace?
MR. HARDIN: Model uncertainty was certainly used as a
concern in the current confidence goal and in terms of assessing -- I'm
sorry, in the current confidence. In terms of assessing the confidence
goal it would be necessary to extrapolate where we think we could be and
that also has been done, but I understand your concern in that we have
not specified how the models would be changed --
DR. STEINDLER: I don't want to know how the model is going
to be changed. The thing I am trying to find out is whether or not this
confidence goal, you know -- the argument for the confidence goal being
at the level it is seems to be based entirely on the acquisition of data
and does not seem to address something that you are going to do to
enhance confidence that the model uncertainty can be reduced. It is
that difference that I am looking for.
I mean you have great data but your model is lousy so
general extrapolations --
MR. HARDIN: Well, I have given it that sense, and I would
allude to some of our peer reviews which have told us that we don't have
enough data. With more data the models will improve and that is really
what we are saying.
We understand where the models are the thinnest.
DR. STEINDLER: We haven't got enough time to work on that
one. I'll just let it pass.
DR. GARRICK: Well, of course if we get enough data, we can
simplify the model and in the limit we don't need a model if we have
enough data.
DR. FAIRHURST: If you have got the wrong model, the
interpretation of the data will be wrong.
DR. STEINDLER: Exactly. The acquisition of data is
normally driven by some picture that you have called the model. If you
continue down that road you probably aren't going to make a whole lot of
important changes to the model and the model uncertainty remains as an
unresolved issue. That is all I am saying.
DR. GARRICK: Yes. Lynn?
MS. DEERING: I just wanted to add something to this and
this was based on something I heard Abe Van Leuyk say at the NWTRB
meeting, and Ernie, tell me if I have got this wrong.
He was implying with respect to confidence goals if a low
confidence goal is assigned if DOE believes they have already -- there
may be a lot of uncertainty but DOE believes it has captured that
uncertainty in the current model, therefore it is bounded. A high
confidence goal is given to those areas where the modelling is not
expected to change much for the worse. In other words, dose could go
down if they work on refining the model to their advantage, but it is
not -- they are not going to put the money into a model where they feel
the dose isn't going to get worse.
Does that make sense? That is what I heard out there.
MR. HARDIN: I wouldn't say that at all.
We are very keenly concerned with defensibility.
Continuing on, on some of the ongoing tests, we have come
crevice corrosion fiber optic probe work that we are developing, trying
to understand the chemistry of the crevice between the -- at least
currently, the carbon steel and the alloy-22. What we will be doing,
and I will mention later some of the work for some of the other
combinations of materials. What we have also done here is a kind of
quick and dirty test where we have put in some PH papers between the
different components after the reactions have taken place. We do that
under liquid nitrogen. We allow it to heat up and we measure the PH,
and we are getting a relatively good comparison.
Some other interesting tests that we are performing are
relative humidity tests. As you know, after the repository cools down,
the relative humidity rises. We have done some thermo-graphic analysis
experiments to determine the critical relative humidities for these
materials, and it depends to a large degree on the condition of the
surface whether the condition is oxidized, salted, or unsalted, it will
change the critical relative humidity at which corrosion will initiate.
So those tests are underway in humidity chambers now, and we have just
started in the last month drip testing onto some of these heated
surfaces to study electrolyte chemistry and follow the corrosion process
over time.
In addition to that, we have also been working in the last
month on some evaporation chemistry, and trying to compare that with
what we would determine from calculations. The problem, as you know, is
that, as you get to more concentrated solutions, a lot of the analytical
modeling breaks down. So we are trying to enhance that and come up with
some reasonable comparisons.
As I mentioned in the beginning, we do have some
microbiologically influenced corrosion work underway. That has been
underway for about a year. What we are focusing on is nutrient
requirements, biofilm generation and corrosion of the corrosion
allowance and corrosion-resistant materials under low and high relative
humidity conditions. In fact, in the relative humidity chamber, we are
adding some of these biological couples so we can get some information
there on the corrosion performance under those high relative humidity
conditions.
My last bullet here, there was some interest on the part of
the design team on coating the carbon steel to enhance its
corrosion-resistance, and we have done a series of evaluations with a
variety of different oxide ceramics, including aluminum oxide, magnesium
aluminate spinel, titanium oxide, and a variety of different plasma
spray processes, including standard plasma spray, high velocity
oxy-fuel, detonation spraying, et cetera, and we found that the high
velocity oxy-fuel process gives us a high density, at least 98 percent
density coatings, and we have those testing -- under test, rather, in
the corrosion test facility, both in solid condition and with specimens
that have saw cuts in them right through the coating.
DR. STEINDLER: Did you ever consider using other alloys as
coatings, like gold, for example?
DR. STAHL: No, we have not.
DR. STEINDLER: It has got a fair corrosion resistance, I
would think, considering how much money you are spending, as it is.
[Laughter.]
DR. STAHL: A gold-plated --
DR. STEINDLER: You lost in the noise. It may be a tough
sell to the public, though.
DR. WYMER: Are you doing any of these tests under radiation
fields?
DR. STAHL: No for the container materials. What we have
done is an analysis of what the radiolitic corrosion rate might be based
on the literature and the dose at the surface of the package, and we
have just completed a report on that subject, and we find that there is
no radiolitic corrosion enhancement that we need to work about.
DR. WYMER: But you haven't look at, for example, titanium
under those conditions?
DR. STAHL: Yes, we have. And, again, there is no impact.
DR. WYMER: A little surprising since titanium forms a
peroxide complex.
DR. STAHL: Actually, I think the -- according to Dr.
Shoesmith, the corrosion of titanium improves under a radiation field,
but there is a report that he has generated on that subject.
Let me talk about the waste package alternative designs.
You have heard about those yesterday. One of the primary designs is the
2 CRM design, which is Alloy-22 outer barrier over a titanium inner
barrier. Here we are not quite ready to conclude on the thickness of
those particular barriers, but we need as a minimum 20 centimeters --
excuse me, two centimeters of Alloy-22 and probably a
centimeter-and-a-half of titanium for the corrosion performance, but we
may need to enhance those thicknesses in order to provide mechanical
rigidity. There is some consideration of going up to perhaps five
centimeters for the Alloy-22, that is one --
That's one option. Another option is to put an internal
structure of stainless steel to provide additional strength.
DR. HORNBERGER: Do you think we should buy nickel futures?
DR. STAHL: No. The impact on the market's going to be
fairly small. In fact, we've looked at that for titanium as well.
Some of the shorter-term tests to address some of these new
materials issues. We do have some short-term tests under way, and we do
have several more planned to look at these corrosion-resistant
materials, particularly to address some of the issues for the
alternative waste package designs.
If you have titanium and Alloy 22 crevice, for example, what
are the impacts there? We've done some preliminary galvanic cell work
with those samples, and we feel that the galvanic current is small
because they're very close in the galvanic series. But we'll need to
evaluate that.
Stress corrosion cracking for each of those materials is a
concern, although I think those materials are fairly immune under the
conditions that we have in the repository.
Hydrogen attack is a problem for titanium alloys, but we're
currently studying titanium grade 7 which is a palladium alloy and has
about .15 to .2 percent to weight percent palladium. Fairly immune to
hydrogen attack, but we're going to have to confirm that.
The issue that Dr. Hardin mentioned about the Alloy 22, its
phase stability, there is the potential for phases to precipitate as a
result of thermal aging, mu phases, sigma phases. What we plan to do
there is we have a full diameter mockup that has been generated of Alloy
22. This is currently at Lawrence Livermore. It will be sectioned to
provide some samples for phase stability studies both in the welded and
welded and thermally aged condition. And as a corollary to this, we
have some samples that we've obtained from Haynes that have been aged at
over 40,000 hours at 427 C. We're looking at the phases that have been
formed in that period of time, and we will be subjecting those samples
to corrosion testing.
Very briefly, for natural analogs, we do have models that
describe the potential mechanisms for many of the materials, but for
some of the newer materials we're going to need to develop those. For
example, particularly with titanium. We'll have to develop those for
the site recommendation and the license application. That process will
include the evaluation of natural analogs and partially validating the
performance models, and in helping to understand the long-term
degradation processes. We have reviewed the existing literature, and I
have asked the model people, particularly at Lawrence Livermore Lab, for
these containment materials to incorporate this information into their
models.
Last item I want to talk about is Zircaloy cladding
performance. We're looking at Zircaloy cladding as part of the
performance of the spent fuel waste form. Vapor exposure to defective
cladding and drip testing into rod segments are currently under way at
Argonne National Laboratory. What we're doing there is we take about
six-inch-long segments of spent nuclear fuel rods, we have several that
have different ranges of burnup, anywhere from 38,000 to about 70,000
megawatt-days per metric ton. We drill some holes in them and are doing
some of these vapor exposure. We also have a similar test which is
sealed. It has swage like fittings on each end, and we drip water into
those tests.
Those tests have just started last month or the month
before, so we don't have results there. One interesting thing that we
are going to do is in the vapor phase tests where we have an autoclave
running at 175 degrees centigrade, we'd like to put a small capsule
which has J13 water in it, and the reason for that is we'd like to see
whether we can speed up the interaction of any of the silica waters with
the fuel. As you may have heard previously in some of my presentations
when I addressed the issue of spent fuel dry oxidation, where you can
convert UO2 to U308 and hence split the cladding, we want to determine
whether any of the silicate phases would do the same thing. So that's
the objective of this modified test.
There are some tests planned to look at some of these other
critical issues with Zircaloy. Hydrogen attack is one which is very
important, and the potential for crevice corrosion given that under some
conditions you may have some ferric acid chloride creating a crevice
with the Zircaloy in those collapsed fuel assemblies.
And lastly, models are being developed for the important
degradation mechanisms that have been identified.
In summary, I've talked about the testing and modeling
programs that respond to the key materials corrosion issues that were
identified. Those included waste package materials lifetime, use of
natural analogs, and cladding performance.
DR. HORNBERGER: Thank you, David.
Questions.
Marty?
DR. STEINDLER: You've got something like depending on who
you listen to, either three or four years to come up to speed and
validate in some fashion or another the corrosion models. Aside from
the existing uncertainty as to the environment in which the subject
metals are going to corrode, which seems to me casts some doubt as to
whether or not you're doing the right experiments, why do you believe
that you're going to be able to arrive at models that are demonstrably
correct and obtain data that is adequately useful for extrapolation to
the time periods you're going to have?
DR. STAHL: That's an excellent question.
Certainly and unfortunately we've had a late start on doing
the corrosion testing that's required to form a sound basis for models
and model prediction. Long-term tests have only been going on for about
two years. And as I indicated, we'd just be taking some two-year data
very shortly. What we hope to do, and have been doing, is a series of
accelerated tests to try to understand the mechanistic changes, if any,
over the range of conditions that we would expect, and hence give you
move confidence that the model that you're based on the performance
condition tests basically do the job for you.
Hopefully, we will be collecting additional information as
we go into performance confirmation, and that would hopefully confirm
the results that we've seen. So all of these tests will be continuing.
We will be putting additional samples into those tanks so that we can
have test data out to perhaps 50 years or so to confirm indeed that the
material is behaving the way it should.
We also, as I indicated, have some short-term tests looking
at electrochemical response. It's not as good as a service condition
test because it is under accelerated conditions. But again, that gives
you some support that the results that you've seen are reasonable.
DR. STEINDLER: What sort of ceramics are you looking at?
DR. STAHL: Well, as I mentioned, mostly oxides, the
magnesium aluminates. Banel seems to be the best. It has the best
coefficient of thermal expansion and has a blackish type finish, so it
gives you good emissivity response. But we've looked at some others.
As I've mentioned, titanium oxide, aluminum oxide. Hafnium oxide is one
that has been suggested, but it's a little more difficult to work with.
DR. STEINDLER: Aside from gold, is there any material that
will not corrode in the media that you're looking at?
DR. STAHL: Well, you can get any material to corrode under
aggressive conditions. The key is determining the conditions that you
have at the site and relating the material selection to those
conditions.
What we would hope to do with some of the alternative
designs -- for example, with the alloy 22, we had developed previously a
model which gave corrosion rate as a function of chloride pH ferric ion
concentration, for example, and we're using that same model to look at
the corrosion of the outer barrier where you don't have aggressive
conditions for the most part, you have benign ground waters.
One of the things that you might get is some crevices form
because of the salt deposits, and that's the purpose of our relative
humidity chamber drip test, to try to evaluate the performance under
those conditions. But we think that the current model can be extended
to work under what we think the conditions would be for that alloy 22
outer barrier as opposed to the creviced case against iron.
DR. HORNBERGER: Charles?
DR. FAIRHURST: A couple of things. Steve Broucom mentioned
this morning the upper temperature limit of about 350 C. What's the
problem at that point? I mean, in other words --
DR. STAHL: The temperature limit of 350 C was generated
many, many years ago -- I can't remember the date, but it's prior to
1987 -- and it came about in discussions with the three repository
programs, and they came up with that limit based on a fairly cursory
examination of the creep rupture data, which they thought was the
primary mechanism for failure.
DR. FAIRHURST: Okay.
DR. STAHL: And we've kept with that limit on our program.
The literature out there indicates that for the most part, if you do
have some failures, they're going to be fairly localized pinhole
failures, and that's part of the key of the Argon test, is to determine
whether indeed you have some localized pinhole failures, whether that's
going to lead to a cladding failure and hence greater exposure of fuel.
Right now, in TSPA-VA, there's a fairly crude model for
cladding performance, although some might argue it's non-conservative,
but they say that for each patch that you open, you have ten centimeters
squared area exposed, and that may be very conservative. On the other
hand, they don't look at the total number of failures that could occur
in that particular package itself as far as the cladding is concerned.
So what I'm suggesting is that the Argon test might shed
some light to say it doesn't matter whether you have small pinhole
failures; it may be that if it doesn't lead to gross degradation, that
you would just have limited area of exposure and you could
conservatively assume that they're all failed.
DR. FAIRHURST: What are the natural analogs that you --
DR. STAHL: There's a host of natural analogs, certainly for
the waste forms -- Pena Blanca, for example, for uraninite; there's a
lot of glass analogs that are out there. As far as metallics, you have
some iron artifacts. There's the Roman nails, there's cannonballs,
there's the Indian obelisk. So we have some information on how some of
those materials behave under atmospheric conditions and under submerged
conditions.
What we don't have is a lot of information on nickel
materials. The only thing that's close to it are meteorites, which are
iron nickel, and recently people have identified josephinite, again
which is an iron nickel mineral.
DR. FAIRHURST: All right. Thank you.
DR. HORNBERGER: Ray?
DR. WYMER: On what basis did you select the upper and lower
pH limits?
DR. STAHL: That came again from the geochemical workshop
that we had. The feeling that most people had was that the range should
be about four and a half to ten, and we felt, to be conservative, we
would extend that and widen that range. So we went down to about 2.7.
It's interesting that subsequent calculations that were done
by Joe Farmer and Kevin McCoy indicated that the crevice pH between iron
and alloy 22 would be about in the range of two and a half to three, so
we were fortunate in that assumption.
DR. WYMER: Okay. And the upper limit was based on
concrete?
DR. STAHL: Yes.
DR. GARRICK: You got into it a little bit with Dr.
Fairhurst's question, but you didn't say a great deal about the
parameter temperature. I assume your tests are varying temperature.
DR. STAHL: In the long-term corrosion test facility, we use
60 and 90 degrees centigrade. For some of the localized corrosion
electrochemical tests, we do a variety of different temperatures. We
have not gone higher than the boiling point at this point, but there is
some interest in going up to higher temperatures based on the results of
that concentration study that are currently underway. There's the
potential with nitrate dominated -- nitrate and chloride dominated
salts, that you might have equilibrium boiling point of about 120
degrees centigrade.
DR. GARRICK: Yes.
DR. STAHL: And if that is confirmed, then it's likely that
we'll be doing some additional tests up at that temperature.
DR. GARRICK: Thank you.
DR. HORNBERGER: Marty?
DR. STEINDLER: Yes. Just one other question. When you're
using 1,000 XG-13 water, the fluoride concentration is now in the
interesting stage. Have you done, you know, a hard look on the role of
complexing agents like fluoride, both on the materials -- the metals as
well as on the waste form corrosion?
DR. STAHL: We have not --
DR. STEINDLER: I couldn't find any of that.
DR. STAHL: We have not explicitly done that, but we have
essentially looked at the results of the testing that we have with the
concentrated salts and have not seen any adverse effects, although the
literature is replete with references. If you do concentrate with a
chloride solution, for example, or a fluoride solution, it's going to
lead to problems. But because of the combination of salts that we have,
you do help, I think, with passivating the surface.
DR. STEINDLER: Do you believe that?
DR. STAHL: Yes, I believe that.
DR. HORNBERGER: Do your conversations, your interactions
with NRC staff lead you to believe that your work on the cladding will,
in fact, result in acceptable data and models to use it in the license
application?
DR. STAHL: I believe so. We have a recent report by Dr.
Tae Ahn, who is in the back, and he had indicated which of the
degradation mechanisms were important and which were not. Our position
is fairly consistent with his. He suggests some confirmatory tests in
some of those areas that I mentioned, and hopefully we will do those
tests.
DR. HORNBERGER: Other questions?
Thanks very much, David.
DR. STAHL: Sure.
DR. HORNBERGER: We are now going to break for lunch and we
will reconvene at 1:15.
[Whereupon, at 12:17 p.m., the meeting was recessed, to
reconvene at 1:15 p.m., this same day.]. A F T E R N O O N S E S S I O N
[1:15 p.m.]
DR. HORNBERGER: It is now 1:15 Garrick Standard Time -- and
we are going to continue this with the schedule. We have the NRC Staff
presentation on VA and Mike Bell is going to do that presentation and we
will just go ahead and get started. Mike?
MR. BELL: Thank you, Dr. Hornberger. Dr. Michael Bell -- I
am Chief, Performance Assessment in High Level Waste Integration Branch
in the Division of Waste Management in NMSS.
I will be talking to you this afternoon about the Staff's
review of DOE's viability assessment, which is still a work in progress,
and I will be talking a little bit about the schedule and where we are
and where we are headed as I proceed through the talk.
First slide, quickly, just an outline of the briefing -- why
we reviewed it -- because it is not always obvious -- what we did, where
we are in the review, and essentially where we came out.
Now the VA, I'd just like to remind people, is not a
licensing document.
It is a document that Congress asked DOE to prepare in the
authorization legislation -- or it was the appropriation legislation in
1997.
Congress didn't specify any particular role for NRC in
review of the VA. However, we are reviewing it as part of our ongoing
prelicensing consultation with the Department of Energy. We also expect
to be asked by Congress for our views on it because, as the future
regulator, we have a unique perspective on the work DOE is doing, and by
statute we have this responsibility to consult with DOE on their site
characterization work and to give them feedback on whether they are
doing the right things to eventually support a license application.
The second bullet -- our focus is mainly on those parts of
the VA dealing with their test plans, design concepts, their safety
case, and future work plans to develop the license application.
Now the VA has four parts. These were actually identified
in the legislation by Congress as things that had to be included. NRC
is particularly interested in looking at the design concept, the Total
System Performance Assessment, the LA plan, and less interested in the
costs. In fact, in our review we didn't look at the costs at all and in
the cost estimates only looked at things like their Performance
Confirmation Test Plans and schedules for some of the work they are
planning to do.
Now we have actually been preparing to review the viability
assessment for quite some time. We have had a series of interactions
with the Department on TSPA VA, some of which in fact the ACNW members
attended. If you recall, I think it was July a year and a half ago,
back in San Antonio.
We have also had technical exchanges with the Department on
the content of the VA itself and in particular we had an exchange on the
LA plan sort of late in the development of the viability assessment.
The hard copies of the viability assessment were actually
received at NRC on New Year's Eve, and we are due to get a paper to the
Commission with Staff comments on the 9th of March. That paper right
now is just about to go into internal management review and I'm
expecting that maybe next week a predecisional version of it can be
provided to the ACNW members to help you get ready for the upcoming
Commission briefing, because we are scheduled to brief the Commission on
the 16th of March on our comments on the viability assessment. Later
that same afternoon the state, the local governments, the Indian tribal
representatives will be speaking to the Commission and then the
following day the ACNW and the Technical Review Board are being asked to
inform the Commission of their views on the viability assessment. I
know you are in a difficult situation in that you won't be needing to
write your letter until the following week, so perhaps the Staff views
will help you prepare for the Commission briefing.
In the viability assessment DOE analyzes the probable
performance of the repository using its reference design, and we
reviewed those analyses of the department.
We also conducted our own analysis of the reference design
using our own TPS, Total System Performance, code. Based on what we
identified -- we did sensitivity analyses as part of this -- and based
on what we identified as the parameters and processes that were most
important to performance, we used that to focus our review of the LA
plan and to look at whether the department was in fact doing the right
work and planning to do work on what our analysis showed to be the most
significant contributors to dose.
In doing our analysis, we, both NRC and the -- well, and the
department, in their own analysis, looked at a 25 millirem, all pathways
standard to an average member of a critical group living in the Amargosa
Valley, 20 kilometers or so from the repository.
In Part 63 we currently have a 10,000 year period of
performance. Both DOE, in the Viability Assessment, and the NRC staff,
in the sensitivity analyses, went out past that. In our analyses, we
carried them out to 50,000 years. And, basically, we looked very hard
at what DOE's performance assessment said was significant, you know,
compared that to ours, and all with a view towards how prepared is DOE
to have the data and the analytical capability to prepare a license
application.
Now, the outcome of our review, essentially, is we don't
think we identified any new issues, that any of the post-closure
performance issues that surface are things that are already encompassed
within the key technical issues the staff has been looking at for the
last several years, and most of the concerns are already documented in
Issue Resolution Status Reports that the staff has provided to the
Department of Energy.
The review, in fact, had a number of positive aspects which
I will elaborate on on another slide, and we did identify a number of
concerns where we think DOE needs to do additional work, or somewhat
different work than is currently planned in order to prepare a complete
and high quality license application.
Some of the positive aspects of the review were that we
established a good communication with the department and contractors
doing the technical work for the department. There was a good exchange
of information during the technical exchanges that we had. DOE did not
provide us a copy of the draft VA itself because that would have
resulted in it becoming a public document and our placing it in our
public document room, but they did provide a large number of supporting
references and other documents that facilitated our review. And,
certainly, in the meetings and the discussions, we are getting insights
into what they were writing in the Viability Assessment.
And they recognize many of the areas where additional work
is needed prior to licensing and, you know, even since the Viability
Assessment has been released, we have continued to have interactions
with them on their work plans and the work that Steve Brocoum was
describing this morning to develop -- what do you call it? -- a
multi-year plan for site recommendation and the license application.
In our review of Viability Assessment, there were a number
of areas where we don't see any major differences in approach between
NRC and DOE. The analyses that are being done, we think are coming to
similar conclusions. The data is either -- we don't have, I guess, big
disagreements with the assumptions, the data that is being collected.
And I have got a list of these areas on these two charts. I don't plan
to go through these in detail, because they are the less interesting
ones, they are the ones where we are in agreement.
Areas where we think there are still things that need to be
brought to closure are listed in the next couple of slides.
Regarding the preliminary design concept, I sat in on a
discussion this morning that I think reflected much the staff's concern.
You know, the reference design is not what I would have had in mind as a
reference design. There is so much still uncertainty about major
parameters of repository design. And then, on top of that, so many
additional options that are being considered, it just creates tension
between having flexibility and the ability to gather the data to support
the design and support the safety case.
So, in our view, one of the things that needs to be done
quickly, and the department is planning to do it this fiscal year, is to
settle on a reference design so that it can focus its program, focus its
future total system performance assessments, do the necessary analyses
and start focusing on the license application.
The next several areas are aspect of the total system
performance assessment where we think there is either weaknesses in the
models, in the data supporting the models, that is not necessarily being
addressed at the rate that we would anticipate it would need to be done
to support a license application, roughly three years from now, it is
three years next month.
And the waste package corrosion is one of the areas.
Important decisions still even need to be made about the materials of
construction, but if C-22 is the material of choice, there is very
limited data and experience with it. Even though there are some
corrosion tests being done, there are questions about fabrication and
the -- well, the possible failure modes that would result from welding
and other fabrication questions that aren't adequate being addressed.
A closely related question is the quantity and chemistry of
the water that will be in contact with that package. The near field
coupled processes that result from a high thermal loading are a very
difficult area to model and predict, and I guess we don't see, in the
tests that are being planned, the necessary work that will answer --
provide the answers to all these questions. And, again, there was a
discussion this morning about you can avoid some of this by going to a
lower heat repository design possibly.
Then saturated zone flow and transport is another area where
data is just very sparse in the saturated zone out to the critical
group. There are plans to acquire some of the necessary data in the Nye
County drilling program, but there are concerns about whether all the
right data will be gathered and whether it will be gathered on a
schedule that would support a license application in three years.
The last area on the chart, igneous activity, as this
Committee knows, the staff feels that it has bounded the probability
question, but there are still large differences between the consequence
analyses that the department has done in the Viability Assessment and
the staff's view of the consequence models for a volcanic event.
The staff's view on this was documented in the Revision 1 of
the Issue Resolution Status Report on igneous activity, and I would
point out that the LA, which doesn't -- the LA plan, which doesn't
indicate DOE plans to do very much work in this area, is already out of
date because we have had Appendix 7 meetings and workshops with them and
discussed the issues identified in the Issue Resolution Status Report,
and there are work plans being developed to refine some of these
consequence models.
Now regarding the LA plan itself, it's a snapshot in time,
and as Steve Brocoum told you this morning, you know, they finished work
on it August of last year. Since the plan has been issued, DOE
continues to focus -- and in fact is very positive. In the viability
assessment they take our key technical issues, do the crosswalk between
their parameters, show where the KTI's are, you know, addressed in their
program, and that was probably another positive aspect of the VA that I
should have mentioned earlier.
They are using our issue resolution status reports in the
planning of their program. They've had workshops to develop work plans
where in fact they take the IRSR's and they walk through the NRC
concerns and talk about well, what work can we do to address this? And,
you know, the question, you know, then will be the implementation of
these work plans because, you know, the NRC staff has seen a number of
study plans in the past that, you know, never actually got carried out.
Now since the VA is not a licensing document, it really
wasn't developed under a quality assurance program, but DOE itself in
its audits of its programs has identified a number of deficiencies in
their quality assurance program, and as you heard from Steve this
morning and as we discussed yesterday morning, there is a, you know,
certain amount of the data that underlies the models that they've
developed, and the analyses that they're doing is of questionable
pedigree.
The Department, you know, has recognized that, you know,
they haven't been successful over a period of years in getting their
hands around the quality assurance issue, and to their credit they are
giving a lot of senior management attention to the issue. And, you
know, NRC is planning to follow very closely how the Department
addresses this problem.
The next thing we expect to see is a root-cause analysis and
a corrective-action program that Steve I think -- is Steve still here?
I think he left. Has said he would provide us and meet with us in April
of this year.
And as Dr. Brocoum mentioned, they are giving very
high-level management attention both at the -- within DOE OCRWM program
itself and within the M&O and they are relying on obtaining outside
assistance as well. And I understand NEI will mention their offer to
assist later when they talk to you this afternoon.
Where from here? Basically as I mentioned earlier there is
a staff paper that we owe the Commission by the 9th of March. The paper
will include a draft letter to Lake Barrett with comments on the
viability assessment that we're recommending that the Commission forward
to the Department. We'll be explaining the basis for these
recommendations to the Commission on the 16th of March. And, you know,
it's assuming things proceed as we're recommending, then we would
continue to interact with the Department in this prelicensing
consultation program to make sure DOE has every opportunity to address
these concerns before they submit a license application. So, you know,
in a general sense that's where we are, and I'm available to answer
questions. I've got a number of KTI leads here, as well as Dr. Sager
from the Center.
DR. HORNBERGER: You brought your backup team; right?
Okay. Thanks, Mike. I'm sure that there are some
questions.
Marty, do you have any you want to start with? Charles?
DR. FAIRHURST: I'm interested in this first staff concern
about the preliminary design concept impact of flexibility of design on
data acquisition.
I'm not so sure what that really means. What has really
been happening is that the notion of a low-temperature repository has
sort of been added because the other one, the high-temperature
repository, has always been on the table. And so presumably data
acquisition, et cetera, has all been going on on that assumption. If
you take the high-temperature part of it out, sure, your data needs
change, but a lot of things become simpler. And so I'm wondering what
is it -- and, for example, whether you use cement or bolts really
doesn't --
MR. BELL: Well --
DR. FAIRHURST: That's all preclosure stuff.
MR. BELL: You have many, you know, other aspects that are
still unclear, like whether or not the repository will be backfilled,
how long they intend to keep it open, you know, really what --
DR. FAIRHURST: But most of those are preclosure issues,
right? Like how long it stays open is just a question -- it's a
preclosure issue.
MR. BELL: Well, it's not entirely separable. I mean, there
may be things that have to be done to keep it open for 300 years that
would have postclosure impacts, and we don't know enough about the
details of designing the repository and maintaining it open for 300
years to know what the impacts are.
DR. FAIRHURST: It's still not clear.
DR. HORNBERGER: I guess what isn't clear is how that would
necessarily impact data acquisition, Mike.
DR. FAIRHURST: Right.
DR. HORNBERGER: I mean, certainly all of the aspects that
you mention will affect performance or could affect performance in some
way or other, but your bullet says the impact on data acquisition.
MR. BELL: Well -- Jim Firth, he's -- try to help me out.
MR. FIRTH: James Firth, NRC. Also, the flexibility of the
design also reflects the waste package design in terms of the materials
and how they're stacked, so there's the issue in terms of failure modes
with the materials and how they are interacting with the natural system
and how they'll perform. So it's not just the high-temperature issue,
but if new materials or combinations of materials are put in place, then
that could also impact data acquisition.
DR. FAIRHURST: Data on what, on corrosion rates?
MR. FIRTH: Data and failure modes of the waste package.
For example, the waste package is a very important component of
repository performance, and if you're looking at different combinations
in terms of the corrosion-resistant material on the outside versus the
inside, you may have different failure modes for the waste package. And
in terms of looking at -- in a comprehensive way to look at what are the
most likely -- the failure modes of most concern for repository
performance, it does take some time to do that. So the concern is that
with the range of flexibility in terms of environmental conditions and
waste package materials for example that it does take some time to
collect the necessary data and to look at the failure modes so that you
are not underpredicting or being overoptimistic in your estimates.
MS. DAVIS: Mike, if I could ask --
MR. BELL: Okay. Jennifer Davis.
MS. DAVIS: Jennifer Davis. I'm team lead for both the
container life and source term, KTI, and the waste package corrosion
KESA.
I think the way that we phrase this is we're concerned with
data acquisition for waste package materials even if the design was
frozen as a reference design, so that the flexibility in the design
simply further complicates that issue.
DR. HORNBERGER: So what I heard you say, Jennifer, then,
even sticking, let's say, just to the reference design, the staff is
concerned about data acquisition to bolster the license application in
terms of the materials?
MS. DAVIS: Right. Exactly. There is an aggressive plan
for testing and what not for the waste package materials. However,
we're concerned that if that's not met or if that's not lived up to,
we're concerned with backing up some of the data and figures, I mean,
excuse me, data and models in the code.
DR. STEINDLER: In your assessment of the TSPA as you
received it, you listed six or seven different items. Did in any of
those the issue arise that your models are drastically different than
their models, and you think that their models have serious problems?
Exclude for the moment in that discussion the question of how well the
models are supported by data, whether data acquisition is adequate to
meet your current needs, et cetera. I'm looking for model uncertainties
and differences in models between what you think is going on say in
corrosion versus what DOE has structured.
MR. BELL: Let's see. And just limit it to the corrosion
model?
DR. STEINDLER: Well, no. To any one of those topics,
whether it's, say, water chemistry.
MR. BELL: Well --
DR. STEINDLER: Is your water chemistry model drastically
different than their water chemistry model?
DR. FAIRHURST: If you put the same input, do you get a
similar output?
MR. BELL: Tim McCardin.
MR. McCARDIN: There are contrasting assumptions in models.
Probably the -- in the release models probably is the easiest one to
typify where for spent fuel they have a much lower or a much higher
release rate for dissolution rate for the spent fuel than we have.
However, it's bounded by the opposite situation for cladding, where we
take no credit for cladding and they are taking a substantial credit for
cladding. The net effect almost cancels each other out, but the models
are actually quite different. Is that the kind of thing you're --
DR. STEINDLER: Well, I'm trying to distinguish between two
people making different assumptions on the same fundamental model of how
the world works versus people having two different fundamental
assumptions on how the world works.
Did I make myself clear?
MR. BELL: I'll have to read that in the transcript.
[Laughter.]
DR. STEINDLER: No, but if you make similar input
assumptions you get the similar outputs.
MR. McCARDIN: Correct.
DR. STEINDLER: If you change your dissolution rate to
theirs and so on.
MR. McCARDIN: Oh -- if we make the same assumptions, we
would see similar kinds of things although there are a lot of other
aspects than just those two because it is the amount of water that gets
into a waste package and et cetera and we have to make those the same
also.
DR. STEINDLER: Yes.
MR. BELL: Let me try to say how I would explain the
difficulty. Basically the department in their analyses of the spent
fuel dissolution makes very conservative assumptions about the
dissolution rate of the fuel which forces them to rely very heavily on
cladding credit and the cladding has to remain intact for very long
periods of time under conditions it hasn't been designed for and we
don't see them gathering data to support that assumption.
DR. STEINDLER: I am trying to back you off that. That is
based on some kind of an end-target description, whether it is 25
millirem or not is immaterial. If you just have a look at the spent
fuel dissolution kinetics and the model that is used to describe the
rate of dissolution of irradiated UO2 -- let's now bear -- we are just
focusing on irradiated UO2. Is the sequence of chemical reactions for
example that you folks are using, NRC, similar or the same -- which is
the model outline -- similar or the same as the one that DOE is using,
or is that the fundamental argument that you have about the reaction of
spent fuel with water?
MR. BELL: Okay -- Brent Leslie?
MR. LESLIE: Brent Leslie from the NRC Staff. Basically the
TPA code was designed with the flexibility to look at alternate
conceptual models of spent fuel behavior, because we have great
uncertainty in terms of water chemistry.
We include a model that is exactly the same as DOE based
upon DOE data which assumes that there are no cations other than
carbonate in solution dissolving.
DR. STEINDLER: That is what I am after.
MR. LESLIE: The second model includes cations calcium and
silica. We have another one that is just a straight release rate, a
user-applied leach rate, so we do capture that type of uncertainty in
models in the TPA code.
DR. STEINDLER: So I guess the disagreement between DOE and
NRC then boils down to one selecting one of those models that was just
outlined and what you think it is and perhaps some underlying
assumptions?
MR. McCARDIN: If we want to agree that that type of
chemistry in the water is representative of Yucca Mountain, we would get
the same release rate.
DR. STEINDLER: Okay. All right, so at least you are
looking at the same universe roughly?
MR. McCARDIN: Yes.
DR. STEINDLER: Well, that is heartening to know.
[Laughter.]
MR. McCARDIN: We are on the same planet, yes.
DR. STEINDLER: Okay. Onward.
DR. WYMER: Marty set the stage for a question that I wanted
to ask. Thanks, Marty.
DR. STEINDLER: Any time.
DR. WYMER: As I am sure you know, Mike, EPRI has quite
recently come out with quite a thick report where they also do what
amounts to a viability assessment and Total System Performance
Assessment and I wondered if you have had time to look at it, then I
wonder if you can answer the question are there any significant
differences in the results that they get or things that they dredge up
that are important different from what you and NRC and the DOE people
get?
Can you answer that question or have you had a chance to
look at it?
MR. BELL: Do you know or the Center know?
MR. LESLIE: I would answer that we haven't had time. We
have been focusing on --
DR. WYMER: I know it came out quite recently, Brent.
MR. LESLIE: Brent Leslie from the NRC Staff. We got it in
and we will probably take a look at it in terms of revising the IRSRs
but we have been focusing primarily on the DOE TSPA VA.
DR. WYMER: That's understandable.
DR. HORNBERGER: John?
DR. GARRICK: The committee is quite familiar with how you
are using the TPA to analyze the design, but I was curious in response
to the first part of the VA, which is the preliminary design concept,
how much beyond the TPA analysis have you gone, and in particular have
you done what I would call an engineering design analysis of the design
where you look at the details of how they have designed this thing, how
they are engineering it, and the impact of operations activities, et
cetera, on that design?
Now I know one of the things you are going to say is that
they don't have a design yet --
DR. HORNBERGER: That is the only thing he is going to say.
[Laughter.]
DR. GARRICK: But this committee has had some concern about
a strong engineering perspective of this project, especially with
respect to the engineered barriers and the waste package, because we
just haven't heard somebody from the NRC stand up and talk to us from an
engineering point of view about the design and talk to us about
fabrication, talk to us about materials, except in the context of the
TPA.
MR. BELL: And that is because our focus in this has really
been post-closure. The only aspects of operational and fabrication and
all are such that we have even considered are the things that then would
have to be considered in post-closure performance.
DR. GARRICK: Well, I am thinking post-closure. I am
thinking of things that you would do in the design and operations that
would impact its long-term integrity, for example.
I think you have answered the question and I think the
answer is no.
MR. BELL: Well -- yes, the answer is no.
DR. GARRICK: You said there are no new issues. You have
articulated the old issues, so to speak. With respect to the old
issues, what is -- if you are able to do that at this point, what are
the candidates, if you wish, for show-stoppers in the eyes of the NRC?
You can list all of them or three or four of them. You don't have to
list just one of them.
MR. BELL: I don't think that there is anything that is on
this list that given enough time and money --
DR. STEINDLER: That is a cop-out.
DR. GARRICK: I am assuming within reason. We have got a
job to do and that is to license this thing, and we have heard about a
schedule, and I think that should be the general framework within which
we answer the question.
DR. STEINDLER: Yes, and here sits the taxpayer wanting to
see what your answer is.
MR. BELL: But there is nothing on this list that is going
to cause us to conclude that, well, the site is just unsuitable and they
shouldn't even go forward. I mean it just becomes a matter of if they
want to be able to prepare a license application that the regulator
would docket, be able to review without many rounds of questions and
have a very protracted hearing debating all of the assumptions and
alternative models.
These are the weak areas that we think additional work needs
to be done and I think one of the areas of concern is in fact getting
the data for the saturated flow model, whether in fact the -- see, the
Nye Country drilling program was designed by Nye County for Nye County's
purposes.
Some of that information will also be useful to DOE for
preparing a license application, but it wasn't really designed for the
purpose of answering all the licensing questions that DOE may have to
address, so that is an area.
I think the waste package -- just whether they will have
adequate data on corrosion rates and failure modes of the materials of
construction to be able to project performance for long times in the
future.
DR. GARRICK: The only other thing I wanted to say, I don't
want to give you any easy questions, is that --
MR. BELL: Why start now?
[Laughter.]
DR. GARRICK: We kind of know the direction that Part 63 is
going, but there's a lot of interest in what happens beyond the time of
compliance period, and what is going to be the NRC's position therefore.
I am thinking in particular of the dilemma of a highly
contained repository that results in a very, very late peak dose and the
dilemma that the better the containment, the worse the dose in terms of
being further out in time and probably higher in magnitude.
Can you share with us what, if anything, NRC is going to do
in that arena? Now of course rulemaking would help a lot in dealing
with it, but surely this is something that is on your mind and is
something very unique about this analysis and license application, and
sooner or later we are going to have to deal with it.
MR. BELL: Well -- as I indicated, you know, in our analyses
we -- for information purposes -- are carrying out the dose calculations
to 50,000 years and even at 50,000 years we are within the 25 millirem
all pathways.
DR. GARRICK: Yes, but it is still going up.
MR. BELL: I guess I have difficulty saying that let's carry
out analyses to a million years through many glacial cycles, look at
super-pluvial conditions hundreds of thousands of years in the future
and using that information it seems like it is a very speculative
scenario.
At least not until now what EPA has considered in the WIPP
situation, it's not what is being considered in legislation that's been
introduced in Congress and I think the Commissioners themselves feel
that 10,000 years is an adequate --
DR. GARRICK: Well, but the committee is already on record
with a letter sort of saying that as well, but I guess in the global
scheme of things we have to be responsive to questions that come up --
MR. BELL: See, like I am aware that the French have
rejected one of their sites because of a scenario where I don't know how
many hundreds of thousands or millions of years in the future the
Straits of Gibraltar are going to close up and the site, the water level
will rise, and --
DR. FAIRHURST: They had two others to choose from and that
was the third one.
[Laughter.]
DR. HORNBERGER: They needed an excuse.
DR. FAIRHURST: There were political reasons why they needed
it.
DR. GARRICK: I didn't expect an answer.
MR. BELL: I know for example that there are plate tectonics
theories that say that the Western United States is going to split off
along West Valley --
DR. FAIRHURST: West Valley? My goodness --
MR. BELL: I'm sorry, Death Valley --
[Laughter.]
MR. BELL: And then essentially the discharge point for
Yucca Mountain is going to be the Pacific Ocean.
DR. FAIRHURST: That helps.
[Laughter.]
DR. FAIRHURST: Think of the dilution factor.
No, but coming back a little bit to WIPP, I think a lot of
this is really in the realm of public acceptance. It is not a
question -- and at WIPP absent human intrusion you could carry that
thing out as long as you want and you couldn't find any release. They
didn't do it just to take 10,000. That is a useful calculational figure
but the whole calculation is based upon human intrusion.
We haven't even started talking about human intrusion at
Yucca Mountain. It is a different kettle of fish, I realize, but the
other thing is that it was not saying you carry it out for a million
years, 10 million years or whatever. It was to the time of peak dose.
Now let's suppose you have four or five different scenarios
or designs and they all comply with 10,000 years. Presumably they would
have different long-term behaviors. Maybe you have an option then to
say the one that gives us the most benign result over the long period is
preferable to the others.
It doesn't have to be an absolute. I think there are some
strategies at NRC a regulator could use to make a determination.
MR. BELL: And I guess what you are suggesting is, you know,
perhaps that is a change, you know, that ought to be considered for Part
63.
DR. HORNBERGER: No, I think that John's point isn't
necessarily change for Part 63 but that in fact the NRC -- we will have
to think about the implications of increasing doses beyond 10,000 years,
and I think it is just a question of how one begins that thinking
process and what one does.
DR. GARRICK: Yes, and as Charles says, we didn't have -- we
don't have that problem on WIPP.
DR. HORNBERGER: Keith, did you have a comment?
MR. McCONNELL: Yes. Keith McConnell. We have been
thinking about that and there are a number of -- it's not like the
calculations aren't going to be done, so the information is going to be
out there and I think there are a number of ways you can incorporate
that information into some sort of licensing decision.
One way is to look at it as a way of -- as you know, in Part
63 there is also a requirement for multiple barriers. Well, if you have
a 12,000 waste package, you still need to demonstrate the contribution
of the natural barrier, and if you look beyond the 10,000 year
compliance period to help you define what the performance of natural
barriers are you can incorporate that information into your licensing
decision to provide a reasonable assurance that the whole system works,
but that is kind of where we are right now.
DR. FAIRHURST: Okay.
DR. HORNBERGER: Marty?
DR. STEINDLER: Let me get back to your favorite topic of
QA. You indicate and probably correctly that much of the data is not,
quote, "properly qualified." I would assume that in the light of how
much effort it has taken so far to get this non-qualified data that
repair of that issue is unlikely, and that I would guess that you could
look forward to future efforts on the parts of DOE to make sure that
their future activities are appropriately qualified and it remains to be
seen how successful they are, scientists being a recalcitrant bunch
under any conditions.
DR. GARRICK: That's only a few of them.
DR. STEINDLER: But a significant -- none of them are
chemists. A significant fraction of the data that is currently being
used, being incorporated as parameters in models is not going to get
redone simply because either the literature from which derive is clearly
uncertain about qualifications, or, in fact, it was not done by somebody
in DOE under qualified situations.
What is your strategy at this stage of the game for allowing
that kind of information to be used?
MR. BELL: Well, I guess there are, you know, several things
that are possibilities. We do have a staff position on how you deal
with this situation, and there are several ways that we would --
DR. STEINDLER: Well, let me remind you that that staff
position would probably qualify the famous paper on cold fusion that was
published in the Electro-Chemical Society Journal, which I think
subsequently has turned out to be probably highly incorrect. So I am
not so sure that that --
MR. BELL: Which method?
DR. STEINDLER: That staff paper --
MR. BELL: Yeah.
DR. STEINDLER: -- on how to qualify literature data that
you haven't got?
MR. BELL: Yeah. Which method is the one you would choose
to qualify cold fusion?
DR. STEINDLER: I would qualify any of it, is what I would
-- I could tell you.
MR. BELL: No, I mean --
DR. STEINDLER: The point is if you apply your methods to
that kind of a paper, and I assume similar kinds of papers, the
assurance of quality is unlikely to be reached. So, you know, I am not
too sure that that is going to work.
MR. BELL: The methods in the staff position are essentially
go out and duplicate the data and get corroborating data.
DR. STEINDLER: Yeah, well, I don't mean that.
MR. BELL: Which was not able to be done for cold fusion.
DR. STEINDLER: Sure.
MR. BELL: It is -- you know, to have a peer review of the
work, essentially, peer review showed cold -- you know, questioned cold
fusion.
DR. STEINDLER: No, the paper was peer reviewed. What I am
telling you is that -- what I am suggesting to you is that there is a
flaw in the staff position at this stage of the game, so I wouldn't rely
too --
MR. BELL: What aspect of the staff position?
DR. STEINDLER: The peer review aspect.
MR. BELL: So I can fix it. Okay.
DR. STEINDLER: You can't, it's too late. The point I am
making is that you have got a considerable amount of information that is
not qualified by your current approach.
MR. BELL: Right.
DR. STEINDLER: But it is going to have to get used. What
are you going to do about that? Are you going to allow it to be
incorporated into the DOE models, or are you going to say, fellows, you
can't use that information and, therefore, come to the conclusion that
you can't even exercise those models?
MR. BELL: Well, one of the things that the NRC would allow
is a graded QA approach where you would look at the importance of the
model, the particular data, et cetera, to total system performance, and
then there may be data that is only sort of loosely related, not among
the most important parameters, where, you know, we would accept the data
of, you know, less pedigree.
But, you know, what turns out to be the key models and the
key parameters they are relying on for performance, I think, you know,
they are either going to have to be corroborated or, you know, some
robust way of defending them in the licensing process is going to have
to be accomplished.
DR. STEINDLER: Well, just as a comment, I would recommend
you look at what DOE has done at a very early stage, like tomorrow. See
whether or not you can convey to DOE those aspects of their important
models that you have some serious question about, that they had best try
and do something about, because time is short. Some of those parameters
you can't get in two years worth of lab work, for example.
MR. BELL: Well, yeah, and I think that's some of the
concerns we have been trying to communicate as well.
DR. HORNBERGER: Mike, I have a couple of questions, in
fact, of that nature. When I look at the staff concerns list, under
TSPA, clearly, from what we heard this morning, and communications, DOE
certainly agrees that corrosion, waste package corrosion amongst the
other aspects of the engineered barrier are important, and the quality
and chemistry of water contacting the waste package. The last two on
the list, we don't see a complete overlap with the concerns that DOE has
put forward in terms of their prioritization. So I would like to take
them one at a time.
If we look at the saturated zone flow and transport, what is
your view as -- suppose DOE didn't do anything else, suppose Nye County
just goes with what they have, does this -- would this indicate to the
NRC that the DOE could not provide a credible analysis for a license
application?
MR. BELL: I am not sure we are prepared to go that far yet.
I don't know, Tim, do you want to comment?
MR. McCARDIN: Well, certainly, the alluvium in the
saturated zone path is, in our view, is an extremely important component
of the geologic setting, to know exactly whether that -- in the VA, they
sampled all the way from zero alluvium to six kilometers. We think that
-- we need to know whether it is zero or some other, you know, fairly
substantial length like six kilometers.
DR. HORNBERGER: But so the point would, if they didn't do
any further analyses and simply then, in TSPA LA, used zero for the
alluvium, this would be an acceptable kind of calculation?
MR. McCARDIN: Well, --
DR. HORNBERGER: I am trying to gauge the strength of your
recommendation to DOE that they --
MR. McCARDIN: The standard is still met.
DR. HORNBERGER: Yes, of course. That's --
MR. McCARDIN: Yeah, I assume. Yeah. If they can get by
with zero alluvium, it would still meet. We can't force them to. I
assume --
DR. HORNBERGER: No, no, I realize that. I am just trying
to gauge, you know, where we are on this spectrum.
MR. McCARDIN: Right. I mean our analyses to date show it
to be a very important part of keeping the doses reasonable, that is
where are coming from.
DR. HORNBERGER: Well, see, now, this goes back to Marty's
question, because my impression is that the DOE TSPA does not show that
extreme sensitivity. Now, is this a different conceptual model?
MR. McCARDIN: Part of that is due to the fact that their
waste package corrosion goes way out in time, the 150,000 year waste
package lifetime on average.
DR. HORNBERGER: So, alluvium for them becomes important
only after the 10,000 year?
MR. McCARDIN: Oh, absolutely. Yeah. Yeah. Now, you see
the -- if you go out to their peak doses, which are 100 millirem and
larger, that is where I think you would have to. We have a more severe
case where the containers fail a lot sooner than theirs.
DR. HORNBERGER: Okay. So then now, again, there is a
concatenation of issues here because John raised a question as to how
these NRC staff was going to deal with doses beyond the 10,000 years.
So if the doses before 10,000 years don't rely on the alluvium, your
suggestion then is that that is okay. DOE may have been right in
assuming that this is not an important issue.
MR. McCARDIN: Well, there is always the requirement for
multiple barriers, and if the reliance is completely on one barrier,
there is a problem.
DR. STEINDLER: Well, it also -- it is also based on the
assumption that the cladding holds as long as DOE. See, the big
difference, I think I sense is that they take no credit at all for the
cladding, I guess, whereas, DOE uses that cladding extensively. If you
take the cladding away, and then take the alluvium away, now I think you
have got a real problem.
DR. HORNBERGER: Okay. Yeah. At any rate, this is pretty
much what I --
DR. GARRICK: Well, I am not even clear of that, because it
sounded to me like we are offsetting the effects between the cladding
and the dilution -- dissolution rate of DOE and the dissolution rate, no
cladding, of NRC.
MR. McCARDIN: Yeah, our release rates are comparable on EDS
given they do compensate.
DR. GARRICK: All right.
MR. McCARDIN: But if DOE, using their release rate, got rid
of cladding and alluvium, you're right, you know, as our -- if we take
those same assumptions, our numbers would go up also.
MR. McCONNELL: Part of this is the complication I think
that arises when you don't have, if I can use the term, subsystem
performance objectives. We don't put in any requirements, specific or
quantitative requirements on the performance of any single barrier or
any component of a particular barrier. What we do ask, at least in Part
63, the proposal, is that they demonstrate it. Now, they can take
conservative assumptions like, you know, zero retardation, or zero
alluvium, and in some way demonstrate, you know, multiple barriers. But
what I am trying to say is the use of conservative assumptions is one
way to get to that point.
DR. HORNBERGER: Yes.
DR. GARRICK: Yeah, but I think that you are also saying
that we have to know what the performance capability is of the barriers.
MR. McCONNELL: Yes.
DR. GARRICK: And the only thing that is absent now is a
specification on that performance.
DR. STEINDLER: But I would go back and argue that if you
move the alluvium contribution from zero to one, you now have at least a
nested barrier, so defense-in-depth can be claimed to include a not very
efficient alluvium retardation.
DR. HORNBERGER: The --
DR. STEINDLER: If it is just a body count, so to speak, of
the various barriers included, you know, whatever the numbers are.
MR. McCARDIN: The barriers, I mean to be a barrier, you
have to get some performance aspect out of it. Just being physically
there is not enough. There would have to be some attenuation of --
DR. STEINDLER: Assigned to it.
MR. McCARDIN: Yes. We would -- I mean to be -- it is
subjective what actually is a barrier, but just physically there would
not be enough.
DR. STEINDLER: That's all I had.
DR. GARRICK: In other words, it is not a barrier unless it
can be demonstrated that it has some impact.
MR. McCARDIN: Yes.
DR. HORNBERGER: I mean there are some still some points to
this that we can have further discussion on, because it is -- as you
know, I have some concerns as to what it would mean to demonstrate that
the alluvium was a barrier, you know, how much data -- we have rendered
all this horrendous problem we always face, and, in particular, in the
saturated zone at Yucca Mountain, as how much data are enough. But that
is perhaps a time for another --
MR. McCARDIN: One very quick response is that, for the vast
majority of radionuclides that are in the repository, it is somewhat
anticipated that retardation factors in the alluvium would be quite
high.
DR. HORNBERGER: Yes.
MR. McCARDIN: And so just that in itself, the retardation,
if you had a border of at least a few kilometers of alluvium coupled
with retardation factors that are actually quite large for most of the
radionuclides, that's certainly part of that answer.
DR. HORNBERGER: Okay. So the last one on the list now, to
me, I'm like the saturated zone flow and transport, some of -- or
perhaps the major part of your concern actually stems from TPA 3, and we
understand this.
Now this committee, as far as I know we have not seen any
results from TPA 3 that would have suggested the last item, and so you
must have done some work that we haven't heard about. Because it's
under total system performance assessment. So what is it about igneous
activity now that has set you off? You said there's nothing new, but
have you run TPA 3 that now suggests that igneous activity is raised to
a higher level?
MR. BELL: Well, actually if you have, you know, an
extremely good engineered system, you can have a situation where, you
know, the base case essentially is zero.
DR. HORNBERGER: Sure.
MR. BELL: The only releases occur when you have some
disruptive event to the base case, and, you know, the analyses, you
know, that we've been doing, you know, in fact have situations were the
contribution to releases during the first 10,000 years do come from
igneous events. When you weight them by the probability, the
contribution of the mean dose is low and meets the standard, but it can
be the only source of release.
DR. HORNBERGER: Okay. So then explain to me again now why
this is on the list.
MR. BELL: It's on the list basically because, you know, at
this stage, you know, even though we can do an analysis based on
assumptions that we're making and, you know, data that we've been able
to gather that shows the standard is met, DOE is going to have to come
in with their own analysis and show that, and, you know, we don't think
the analysis they're doing at the current time would really stand up to
scrutiny.
MR. TRAPP: Can I say something? John Trapp.
Along with the fact that right now we don't think the
analysis could stand up to any type of scrutiny, there are a couple
shall we call it kickers, hookers, et cetera, in the whole process that
we're trying to evaluate, and we feel DOE's got to evaluate.
One of the big areas where we've got a tremendous amount of
uncertainty, and right after we got done issuing our first revision of
the IRSR we brought in a series of worldwide experts on volcanism to
take a look at what we had done, and one of the concerns that they
brought up was they thought our assumptions dealing with repository
magma interactions were extremely underestimated. It's an extremely
complicated series of calculations, et cetera, and we're planning on
doing a little bit of more work. But there is a possibility for
instance there that we could be talking about increasing the possible
dosage by about an order of magnitude.
Would this fail the standard? No. By itself it would not.
It would start getting to the point where people are starting to scratch
their head and say that it might give you some, you know, concerns, but
it still wouldn't fail the standard.
Now there's another area that's got to be taken a look at,
and it's really a question of making sure the DOE does answer the whole
concerns. I'm sure you've heard about things like the Wernicke paper
and this type of thing. There's questions that are out there as to what
is the right recurrence rate and all this other kind of thing.
Now if you're doing an analysis where you're talking about
total risk, you've got to address these concerns. If you stay with the
probabilities we've got right now, no, we probably are not going to have
a problem.
Let's jack those up an order of magnitude like Warnicke is
suggesting. If you jack that up and you end up with these problems with
repository interaction as we think they might go, then all of a sudden
you are over. Do I realistically think that this is the right answer?
No. I don't think it's the right answer, but I think somebody has got
to do enough analysis to make sure it's covered.
Now that's where we're coming from. If you take a look at
what is in the license application plan, because basically say under the
area of igneous activity they're not doing anything. That's
oversimplifying, but that's basically what they're saying.
Mike has already mentioned that since we've had the license
application plan, there has been some workshops, et cetera, and DOE has
put together some plans, et cetera, which I think have a very good
chance of putting this whole problem to bed. What we need to see is are
they implemented. If they're implemented, we should be home free.
DR. FAIRHURST: Could I just comment, because I read the
papers that came from Bristol, I think, right, and Cambridge.
MR. TRAPP: Yes.
DR. FAIRHURST: And at least from my reading of it, they
made the assumption that the drifts were open.
MR. TRAPP: Yes.
DR. FAIRHURST: And the likelihood of drifts being open is
not time-independent. I didn't see a particular time of reference for
that analysis.
MR. TRAPP: It basically was assumed in there that yes,
they're not backfilled drifts. Now if you take --
DR. FAIRHURST: No, but even if they're not backfilled --
MR. TRAPP: Let me carry that a step farther, though. If
you take a look at the effects of volcanism, basically volcanism goes
totally backwards from anything -- any of the other processes. You've
got to worry about volcanism in the first few thousand years postclosure
because of the decay, et cetera, and hazardous flows. After you get
past say about 5,000 years, the effects have gone down tremendously. By
the time you got down to 10,000 years, it's really a very minor
significant contributor. So what you're really looking at in this case
is what are the initial effects of which case if the thing is not
backfilled, hopefully it's still, you know, standing. Now when you're
past, you know, 10,000, 30,000 years, no.
DR. FAIRHURST: No. If it's not backfilled and it's subject
to seismic -- first of all, if it's a no-heat repository, you're in an
extensional environment and the roof is the most potent place for
anything to fall out. Right? Got very low confined pressure. Shake
that a bit and it'll come down. And so it would progressively migrate
out, covering the packages, and the open area would be on top. So if
there's any magma coming in, I think it's preferred pathway would be
above the packages.
If you backfill it, then you don't have a preferred entryway
down to the packages.
MR. TRAPP: Very true.
DR. FAIRHURST: So I'm not sure that analysis is fully
realistic. You know, to take an open repository, anything beyond 300,
400 years, down to me is stretching it a bit.
MR. TRAPP: One of the things --
DR. FAIRHURST: Heat it up, it gets worse.
MR. TRAPP: One of the things that they've done on that
analysis, and again it's the back-of-the-envelope-type thing, but they
assumed that you had a drift that was totally full.
DR. FAIRHURST: Right.
MR. TRAPP: Of backfill. With the pressure differential
between the magma and the backfill, et cetera, you could basically build
up almost enough pressure to blow out that whole drift.
DR. FAIRHURST: No. No way. No way. Now you're driving --
you're driving that magma up at approximately the horizontal stress,
right? And it's coming up vertically.
MR. TRAPP: This is coming up at about 8 megapascals. Yes.
DR. FAIRHURST: Yes. Okay. And so it's -- if it's
backfilled, how can you generate -- you try to move backfill, you're
going to have a big pressure drop in just the frictional resistance of
moving it.
MR. TRAPP: Then you build up the pressure again.
DR. FAIRHURST: Yes, but the pressure --
MR. TRAPP: The point it --
DR. FAIRHURST: Can't get anywhere.
MR. TRAPP: The point is I will agree with you that if the
place is backfilled that the problem diminishes considerably. We're
going with a reference design where it's not backfilled. And no, we
aren't talking about the falling et cetera --
DR. FAIRHURST: Backfill does not mean not collapse.
MR. TRAPP: No, and agree with you totally. But we don't
think the thing is going to totally collapse, et cetera, in a couple
thousand years.
DR. FAIRHURST: Well, we'll see.
[Laughter.]
MR. TRAPP: It is a big concern. And if somebody can give
us an analysis as to how much it's going to fall in, we can do the
analysis then.
DR. FAIRHURST: This may be taking it to extremes, and
you're hedging a very important point, in that most of the sort of
estimations of stability of tunnels are based on engineering designs
which somebody will tell you they've seen a thing the Romans built still
standing, but that was built in a particular material at a particular
depth. And there's no doubt that other material, such as tuff and so
on, which are not quite -- have a tiny dependence strength.
If you take the situation at Yucca Mountain as it stands,
it's -- in an extensional environment is the potential of blocks. If
you heat it up, you change that dramatically, because that will probably
crush the outer rings. But I think if you try to extrapolate the
strength for a period of time, to do it over several hundred years it's
quite likely that strength is going to -- now the other thing that's a
factor of this is the span. The bigger the span. And you've conducted
nuclear tests there where you've taken some of that stuff and pit it,
and it has come down immediately over a large span with a nuclear
collapse.
So you can say that over a period of time there's a very
good probability, and most of what we're doing in calculations are based
on estimates of that thing must -- and if it falls, it's going to fall
from the top down. You build up a bulking affair which will fill those
drifts whether you put backfill or not.
MR. TRAPP: Right. And then you're starting to talk about
what is the actual thermal period that you're dealing, which time are
you extension, et cetera, this type of thing.
DR. FAIRHURST: No, no.
MR. TRAPP: And it depends again on the whole design.
DR. FAIRHURST: It's an open tunnel, a level of the -- where
the canisters are lying is an extremely pessimistic assumption.
MR. TRAPP: Which again is why it's -- I'm talking about the
fact that we're dealing with a backwards from every other scenario.
DR. FAIRHURST: I think you can probably do some
calculations.
MR. BELL: Well, you see, Dr. Fairhurst, I think this is a
good example of the kind of exchange we're not having with DOE on these
kinds of issues, because their analysis, you know, makes assumptions
that essentially make the problem go away rather than stepping up to the
table with good, you know, engineering and scientific arguments.
DR. HORNBERGER: But let me turn it around and focus on NRC
rather than DOE. I think that from our standpoint, the ACNW, we would
be much more convinced if you came to us not with, gee, this might
happen or that might happen or this might be a consequence, but if you
actually sat down and did some computations and said, yes, it's -- and
it can't just be a compounding of well, Brian Wernicke is going to up
the probability by an order of magnitude and these drifts are going to
be open and magma is going to come into them and, and, and, and, and
looking at a worst case consequence, that doesn't give us any confidence
that this is an issue. What we would like to see is, my goodness, you
know, when we take into account both the probability and the
consequence, this is, from a total system performance case, an important
issue, and we haven't seen that. And despite what John just said, I
mean, that's -- he's saying -- he's speculating and saying, well, this
might happen, we need to put this to rest.
I would rather see the NRC -- you have your TPA-3 code --
come forward and come to DOE as well as us and say, look, we did this
analysis, we think this is a problem, rather than, you know, being in an
arm-waving situation where you say, this might be a consequence, go
prove to us that it isn't.
MR. McCARDIN: Tim McCardin. We have done the calculation
with our code, and I thought what Mike was saying, and John also, that
we are not aware of a large dose implication, okay? It meets the
standard. Generally, our calculations to data, it's around a millirem
when it's probability weighted. The issue isn't so much our
calculation. DOE is the licensee. We can't do the license application
for them. They need to come in with a calculation, and I think that's
why it appears more that --it's not a threat, but if you don't calculate
it, then it's -- where do we go from there?
DR. GARRICK: Yes, but I think the question we're raising is
that the issue kind of got back on the table not because of anything DOE
did, but because of evidently something that the NRC did. So you sort
of put the bait out there for us to raise the questions in this way.
MR. BELL: Well, I would say it's never really been off the
table as far as the consequence analysis is concerned. I mean, I think
when we last interacted with the committee on this issue, we told you
that the -- you know, we thought we could bound the probability
question, but the --
DR. GARRICK: You can't bound the probability and vary the
consequence. It's logical incompatibility. And that's one of the
things that causes us concern. You don't go around bounding the
likelihood of an event and then change the event. Every different event
has a different probability associated with it, so it makes no sense to
do that. I mean, if we start decoupling the probability from the
consequence, we can come up with any kind of cataclysmic event that will
stop this project immediately. So it's a nonsensical approach.
MR. McCARDIN: Yes. There wasn't a suggestion we were doing
that. I mean, you're right, different events have to have their
probabilities factored in, and that would be done.
DR. GARRICK: Yes.
MR. McCARDIN: Yes. That's absolutely correct.
DR. HORNBERGER: Other questions.
DR. WYMER: Or comments.
DR. HORNBERGER: Or comments.
Thanks very much, Mike. Appreciate it.
DR. STAHL: Will you take comments from the floor?
DR. GARRICK: We'll take a comment from the floor.
DR. STAHL: David Stahl from the M&O.
Mike, you talked about a limited data set in regard to alloy
22. That's certainly the case because the alloy has only been in
existence for about 20 years. I did mention alloy C where we had that
exposure plate. That alloy goes back about 60-some-odd years. And
stainless steels, of course, only go back some 80 to 100 years, 90
years. So certainly, we do have to get more data.
Now, in our plan, at least for the waste package, we plan to
use qualified data for our models, but we will utilize and identify
unqualified data that we'll use in a confirmatory fashion.
So I wanted to make that point.
But I did have a question for you. You talked about welding
issues for alloy 22, and I thought that we had resolved many of them or
were working on many of them and I wondered what specific welding issues
you had in mind.
MR. BELL: Jennifer, can you help respond to that?
DR. HORNBERGER: Jennifer, I would caution you that this is
not a technical exchange.
MS. DAVIS: Okay.
DR. HORNBERGER: So try to give David the brief answer.
MS. DAVIS: Okay. The brief answer is not only some of the
welding issues, but some of the shrink-fit issues. And we're concerned
with the fabrication in general in relation to juvenile failures, which
of course you all are a little more optimistic perhaps than we are. So
it's a combination of things and I wouldn't say anything, you know,
specific as to the welding except of the heat affected zones for the
un-heat treated final weld.
We're also concerned not solely for the welds with some of
the localized corrosion aspects of C-22, which we really haven't
mentioned yet in this session today.
DR. HORNBERGER: Okay. Thank you.
John, I will turn the meeting back to you.
DR. GARRICK: Okay. Well, thanks, Mike. That's the way we
like it -- plenty of time to ask questions. I think what we'll do now,
since we have a little space in our agenda, we're going to squeeze some
letter-writing activity in between now and when we have our next agenda
item, which is a discussion from the Nuclear Energy Institute. But
before that, I think I would like to declare a break. So let's take a
15-minute break.
[Recess.]
DR. GARRICK: The meeting should come back to order and we
are on the record now, I assume. We are going to now hear from the
Nuclear Energy Institute and we are going to hear them talk about high
level waste initiatives, and I guess it is going to be done by Marvin
Fertel and Steven Kraft. And you are going to just talk to us from
there, face to face.
MR. FERTEL: Face to face.
DR. GARRICK: Where are the viewgraphs?
MR. FERTEL: Thank you, Mr. Chairman. Well, we figured by
now you had probably seen on the order of 200 viewgraphs and we would be
nice and gentle and --
DR. GARRICK: All right. Thank you.
MR. KRAFT: We don't want to be confused with federal
employees either.
MR. FERTEL: No, seriously, we appreciate the opportunity to
come before the Advisory Committee again. We expect we will be back
again as this whole process moves down the road. I think that from the
industry's perspective, we were quite pleased with a couple of
occurrences over the last 60 days.
First of all, we were pleased that the department got the
Viability Assessment out on time, almost as a Christmas present, that,
fundamentally, they stood behind the science that was there. They
recognized the uncertainties that they still had to deal with. And we
thought that it represented a pretty good snapshot of at least what they
had done to date, and we were pleased that they were willing to stand up
tall and challenge them on a number of places, even though there is
still a lot of work that they need to do.
We were also pleased that they laid out a lot of plans for
going forward and the plan probably of most importance, maybe from the
NRC's staff's standpoint, was their licensing application plan. And I
guess the way our folks that have looked at it have commented, they
thought the plan itself was a pretty good plan. The question was could
they implement the plan as written. The plan was decent.
In licensing space, the other thing that we are certainly
very pleased with was that the Commission moved forward and issued Part
63. And our look at the pre-decisional version of Part 63, and our
relatively quick review of the version that just came out last week is
we think Part 63 is going down the right road, the right way. And while
I am sure we will have some comments, and certainly some questions, we
are very pleased with Part 63 being out.
Part 63, and, clearly, from what the Commission said in
issuing it, they recognize the importance of Part 63 as part of the
critical path to moving down the road. And we appreciate that, as do
all the contract-holders that are sitting there with waste on their
sites and want to see things move. So moving down the road right now is
really important from the industry standpoint.
I think you realize that we are still in the process of
working with the Congress towards legislation which we think is still
necessary to move waste off of power plant sites. We see the current
situation continuing to jeopardize a number of the plants, continuing to
be a problem from the standpoint of the shutdown plants that are trying
decommission, and, certainly, continuing to be a real problem from the
standpoint of the payments that are being made into the waste fund, and,
potentially, the lawsuits. And to be honest, we are concerned that the
lawsuits could result in tanking the whole program if we don't see a
solution to this, because if the government decides to pay the companies
out of the waste fund, we don't see the money available to implement
both the repository and any sort of early receipt to the repository
site. So we see that as a real threat and a real problem if this
country is going to have a safe, ultimate disposal.
But on the good news, I think Part 63 makes real good
progress, and we will talk a little bit in detail on VA and Part 63 and
a couple of other things.
As far as the DOE program, I understand that at this meeting
there were some questions raised about the quality assurance aspects of
it. We are certainly concerned about that. I think last time we came
and met with this Advisory Committee one of our major concerns was the
lack of licensing experience that the department has. And while I think
NRC has worked very closely, the staffs have worked very closely with
the DOE staff on technical issues, and that has been really good, on the
NRC side we are looking for some closure and finality on things that the
staff feels should be closed.
On DOE's side, what we are truly looking for is for them to
make sure that what they submit is defensible in licensing space, and,
obviously, an adequate quality assurance program is a necessity for
anything they are going to submit.
DR. GARRICK: marvin, we raised that question this morning
with DOE and, given that you are an association in behalf of the
industry, the comment we made was that one of the bright stars of the
nuclear power industry, in my opinion, has been the maturing of the
approach to the quality assurance and the whole nuclear safety
assessment process that comes under that banner, and that there seems to
be a tremendous amount of expertise and maturity there that could be an
important resource. And we quizzed them on whether or not they were
seeking guidance and help from industry in that regard, since this has
already been flagged as one of their -- perhaps maybe their Achilles
heel.
MR. FERTEL: Well, I think DOE is a relatively large
organization with a lot of players, and certain parts are seeking. Not
all parts. But independent of their seeking, they are going to be
offered, and have been offered, basically, the kind of help you are
referring to, John. We have looked and said the same thing. You were
polite in saying it is a maturing that has gotten us to know what we are
doing. We certainly had our own problems in QA at a number of our
plants in the past, and that forced maturing. And I think that right
now we actually have capability within the industry that has gone
through some -- I think even much tougher QA problems than I understand
DOE has.
So that that expertise and that skill brought to bear on how
they need to look at both solving the problems that they face, but, more
importantly, solving the cultural issues that created the problems, are
the things that we are looking at trying to bring to bear. And we are
not looking to go out and do assessments and point out all the things
they have done wrong. What we want to do is go in and tell them how we
have worked our way through similar or comparable problems, and bring
that expertise to help them.
And we have had discussions, literally, as recently as a
week ago with Lake and others about this, and we are going to proceed to
do that in the near term. So, hopefully, we can bring some of this
experience. And, again, I think that there are parts of DOE that are
seeking. I think there's other parts that feel that they honestly know
how to do it, and they can do it. And if they can convince our people
that have gone through it that they have their act together, we would
like nothing better than to say you are on the right course, your
culture is great, your attitudes are right -- just go ahead and do what
you are doing, it is the right thing, if that is the case. If that is
not the case, I think we can help them maybe make adjustments that will
get them through it.
Steve, is there anything you want to add on that?
MR. KRAFT: Unless you want to know more specifics about
what we are planning on doing, John, I think Marvin's pretty well
covered it.
DR. GARRICK: Thank you.
MR. FERTEL: I think, just to sort of pick up on one of the
other areas that we are thinking we could offer DOE some assistance
right now, and again I understand it may have been a subject that the
NRC Staff at least has asked about, which is kind of design flexibility,
we'll clearly help DOE understand in licensing space the necessity to
have a relatively firm thing for NRC to review.
Obviously you can change it as you get smarter, both in
design or in science or in safety analysis space, but you can't have a
moving target. In fact, from our experience in the past it has almost
been the other way at times when we have gone to the Staff. They kept
moving the ball on us so we learned that that is not a good strategy for
getting anything licensed. We don't want DOE coming in with 35
different design options.
We also think that one area where we should bring some of
our experience is for actually not the repository post-closure design
but to look at the operational aspects over what is probably a 50-year
period of handling spent fuel.
DOE certainly has experience in handling spent fuel. That
is one of the things we keep telling them. They know how to do and they
ought to do it sooner rather than later, so I don't want to imply they
don't know how to handle it, but the industry certainly has a lot of
experience in handling spent fuel at the plants and moving it around, so
I think that is another area where we would be looking to bring both the
experience from an operational standpoint and certainly the experience
from a safety analysis standpoint of what should you look at and how
will you defend it, how will you describe it and deal with it.
MR. KRAFT: If I could add to that, the designs that we have
seen of the service handling facility seems to be done without
recognition that you are operating in a regulated environment. There is
insufficient lag storage. There are insufficient pathways out of the
maze that they have designed, things like that that we think that if
they brought greater regulatory expertise into the process they could
learn.
One of the questions that I have asked continuously over the
last year in my visits out there is when you do a design like that, who
is the regulatory person sitting in the design team, the way we used to
do it at the power plants, saying wait a minute, you know, you could be
faced with some sort of order from the NRC telling you you can't operate
greater than "x" percent of your capacity. What are you going to do
then?
Well, they don't do that yet. That is part of the culture
issues that relate also to QA, so that is one of the things we want to
help them learn how to do.
DR. GARRICK: Yes, and the agency is going through two major
culture changes.
They are going from a research and development organization
to a cleanup organization on the one hand, and to a regulated operating
organization on the other hand in the waste field, and there are some
real chasms that exist there.
MR. KRAFT: We agree.
MR. FERTEL: I think a comment on Part 63 and the radiation
standard. We appreciate the leadership that the Commission and the
Staff took in putting a standard in. We understand the role EPA has to
play. Clearly as an industry we believe That the 100 millirem standard
as contained in H.R. 45 and previous legislation is probably an adequate
standard and we understand what the Chairman said at the hearing the
other day about ALARA and what you might strive for, and that is
certainly consistent with the way we have always operating in power
plant or major fuel facility space, so it is not a surprise.
We certainly have a problem understanding the EPA argument.
Putting aside the fact you can't license anything within their
particular construct --
DR. STEINDLER: Sorry, which EPA argument?
MR. FERTEL: Well, that is a good question. The fact that
you need a separate groundwater standard from a health and safety
standpoint. I thought the Chairman explained it pretty simply, as I
thought Congressman Barton did in the recent hearing, where if you have
an all pathways standard it consumes the groundwater standard and it
would seem like we are trying to protect someone, not just the resource.
If it is health and safety, I have never seen any data on the health and
safety of the water resource as something we protect. It's usually the
person that consumes that water, so if we are trying to protect that
person, if the entire comes from groundwater, so be it. That's all
pathways. Let's look at it that way.
So we appreciate both the leadership the NRC has exhibited
here. We also appreciate probably the awkward situation they may find
themselves in in interagency discussions but anything that we can do to
help we would like to and I would say anything ACNW could do to help,
which I think you have been probably, would certainly be appreciated.
DR. HORNBERGER: That's it?
MR. FERTEL: Yes.
DR. HORNBERGER: As you know, we also agree with that. EPA
is in a rather dicey situation because they have things called drinking
water standards and they have a 4 millirem groundwater standard that
water supplies have to meet, and it has been very difficult for them to
say oh, but for this particular case we will waive the standard.
MR. FERTEL: Things are difficult. I mean it is difficult
to project what is going to happen 10,000 years from now when they seem
to figure out that that can be done. This is a policy call. It would
seem real simple to make the right policy call.
DR. HORNBERGER: But that is what it is. It is a policy
call.
MR. FERTEL: Yes, yes -- so we will see what happens but
again I would like to compliment the entire NRC organization for the
leadership they have exhibited here.
I think John Garrick and I wee talking briefly before we
started about how you would move into risk-informed space. We are
obviously moving aggressively into that space and Part 50 space and we
even are talking about it in Part 70 space right now.
It is a little different there because we are talking about
being risk-informed about what I apply the regulations to, not
necessarily how I make the decision, and I think that one of the real
roles that ACNW can play, and certainly we would do anything we could to
help, would be to foster the dialogue on how to move forward and be able
to make the decision once we have a standard that is the standard we are
trying to meet and we are doing, you know, hundreds of scenarios and
looking at a whole bunch of different probabilistic outcomes. How do
you finally say you know the answer from a licensing standpoint and it
is an acceptable outcome?
My guess is that in Part 50 space, where I think it is a lot
easier to do, personally, because there is a lot more information on
stuff, we are still having tremendous amounts of dialogue within our own
industry to get everybody on the same level of understanding and we
learn things when we talk.
We certainly have the same experience and when we deal with
counterparts in the NRC I think that everybody is striving to do it
right and yet in something where we really think we know it pretty well
we are struggling.
I think here again some leadership, maybe from this
particular advisory committee in a dialogue sense, could be very helpful
to getting everybody to use the terms the say way, to understand what
the terms mean and when we get down to NRC Staff trying to make a
decision everybody understanding how that decision is being made, so I
again would encourage -- I don't have any silver bullet for this and
John had some good ideas when we were talking and I agree with
everything he said.
My guess is that if we asked everybody in this room to give
their version of how this could be done there would probably be 40
different though similar versions of how you would make the decision in
risk space on the licensing of Yucca Mountain, so good dialogue there,
early, is probably very helpful.
I think conceptually the rule does the right thing and I
think conceptually everybody wants to do the right thing.
One of the things we will probably look at as we go through
Part 63 is whether or not the licensing process that is embedded in it
allows for some sort of multi-stage licensing, and at the extreme I
think that we are beginning to feel that there's probably real value to
being able to license the above-ground facility separate from the
repository or earlier than the repository if I don't want to use the
word "separate."
Also there may be value thinking analogy of like a low power
test at a power plant even though you never get a low power license.
You really get an operating license and they just hold you at low power,
whether or not there would be value of allowing the emplacement for
testing purposes of waste in the repository early and again I don't
think we have firmed up our thinking on this but I think just to plant
the seed with the ACNW as you go through it and maybe the Staff as they
revisit some of the thinking there may be value of seeing whether or not
there's things that could be done within the licensing phase that you
are not waiting till the end before you can do anything either above
ground or below ground.
DR. GARRICK: Yes. There is a little bit of experience in
that with respect to WIPP in that DOE had a strategy of an experimental
program that required them to have some real waste and unfortunately it
backfired because --
MR. FERTEL: Right.
DR. GARRICK: -- on examination of what was going on there
it was discovered that the experiments were not going to generate the
kind of information that was timely and what information it did generate
could be generated above ground just as easy and probably easier.
So whatever directions are taken in that regard are really
going to have to be very carefully planned out.
MR. FERTEL: I think what I would say, John, is having the
ability to do it doesn't mean you would exercise it or you could justify
exercising it, but if it turned out you should exercise it and then
didn't have the ability that is probably undesirable.
DR. GARRICK: Right.
MR. FERTEL: So making sort of contingency planning for
having the ability might be a good way to begin to think about it,
particularly for something we are going to monitor and do all kinds of
stuff at for literally a few hundred years.
I think the other thing that jumped out at us right in the
Federal Register Notice on Part 63 was the Commission's moving -- at
least raising the question of informal hearings, and I can state
unequivocally we think that is probably the only way to go for licensing
something like this. We think that in most cases in power plant space
informal hearings make more sense than adjudicatory hearings, though
some places may be both or either would do well.
In this case where you have got probably millions of pages
of material and thousands of scientists, and they are true scientists --
they are not engineers or people who are doing policy stuff -- they are
guys that if you ask them a specific question on the stand they are
going to qualify it 35 different ways if they have to answer that
question with a yes or no, you will never get it licensed and you are
not going to improve the safety analysis, you are not going to improve
the decision-making. You are just going to delay the country from
moving forward with doing something with the nuclear waste, so I think I
could state that when the Commission goes forward in whatever
independent proceeding they do on informal hearings for this, we will
certainly try and justify strongly why that makes sense and we believe
it makes sense, so just as an insight on that.
Continuing, again, the Validity Assessment is good and
moving forward with Part 63 is great. We are looking forward to
suitability, and I think that one of the things that we ought to be
doing within the NRC is figuring out how the NRC is going to implement
their activities, particularly related to the Environmental Impact
Statement that they are going to prepare, what they are going to use
from DOE.
And I think last time we were here, one of the points we
made, and I think it is still valid, is that the DOE and the NRC staff
are going to have to transition soon, when they become a licensee, from
the collaborative nature of the work they have been doing, which I think
is in the best interest of the nation, because what they are doing is
putting the best heads together to try and work on the science, to a
licensee-regulator relationship.
And that transition may not be as transparent or as smooth
as one would like, because, again, you have got a licensee that has
never been a licensee, and a you have got a regulator regulating
something they have never regulated before. So there is going to be
comfort level on both sides to want to work together like they have, and
I think they are going to have to begin to think -- I know they are
thinking, but I think that, just like we said, the culture required for
the DOE QA program is different than maybe what they are used to.
I think the culture for the licensing phase of this will
require both sides to behave a little bit differently in order to
certainly maintain the integrity of the process. I don't think they
would do anything wrong if they didn't, but I think that there will be a
perception. And to do that right, some of the planning will have to
take place, literally, over the next 18 months on what can be used, what
can't be used, and ER and EIS space. What suitability means to NRC, and
what is going to happen with the license application once it gets
submitted.
Steve, do you want to add anything on that?
MR. KRAFT: The only thing, and a question I have raised
with NRC staff before, is what their current plan for how they fit into
the suitability determination, which is a -- it is the essence of
policy. It is a combination of a technical and a political
determination, because the President gets to make the decision in the
long run, and there was never an assumption that the President would be
a geoscientist when the time came.
So you have got this decision coming, it is unreviewable,
which means the President gets to make whatever decision he wants. The
NRC has a role to play under law, they have to say something about the
decision or about the DOE work at the time into that process. They have
linked it, I believe, to an existing internal NRC process that may or
may not be correct. They may be putting too much into what they have to
say in that suitability determination, or they may not be putting enough
into it. But from I heard about it, I am concerned that NRC is going to
make, I think, too much out of -- too much of a licensing type decision
out of the input into the suitability process, and they need to
recognize what that suitability process is as a combination of a lot of
different things, and, in essence, a policy decision as opposed to a
pure technical decision. I think that bears some consideration and some
discussion in public as to how that gets done.
MR. BELL: Would you like a comment from the staff?
MR. KRAFT: Go ahead, Mike.
MR. BELL: Well, under the statute, our role is only to
comment on the completeness of DOE's site characterization and waste
forum development work. And we don't see that as entering into the
policy arena. It is basically -- given the information they have at the
time of the site recommendation, if they then go forward and six months
later submit a license application, which is what the statute calls for,
we would not reject that application just because it had insufficient
information. I would say that is the role we see ourselves playing at
that time.
I mean, so that the President doesn't then find himself in
the position of going to Congress and Congress, you know, potentially
overriding a state objection, it all goes forward and it comes to NRC,
and then NRC would say, well, they haven't done enough work. I mean
that is what I see our role in that, just to avoid that political
debacle.
MR. FERTEL: Mike raises in his answer, which sounds find,
raises an interesting point. As opposed to other projects that at least
I am familiar with, licensing, you know, whether it is a plant, which
sometimes has taken way, way too long, but, typically, is not a 50 to
100 year licensing overview type thing, we have a situation here where
you are going to file -- if all goes right, you are going to get a
license application in 2002, and DOE is going to expect that they are
going to get an answer a few years later, and then they are going to
build something. And whether we agree they can make 2010 or not is
probably not relevant, because it is somewhere out in, you know, the
2010 to 2015 time period if they make the 2002 date.
But, fundamentally, you are going to then spend about 30 or
40 years loading it. The whole time you are going to be observing it,
and testing, and verifying, confirming stuff, and still under a
licensing banner. Then you are going to spend another, you know, 50 to
250 years in some sort of confirmatory role as a nation. I don't mean
any of us at this point.
It seems like you are not going to have, and no one believes
we are going to have 100 percent certainty in 2004 or 2005 when the
license is issued, and if you did, you would wonder why you are going to
spend billions of dollars after that doing all the things we are going
to do to make sure that we were right. And I think one thing that we
all need to think about, and I certainly don't have the answer, but the
question I think is real, is you don't -- you won't have 100 percent
certainty, and we shouldn't pretend we will.
But you don't need it, because you're still going to have a lot of time,
you're doing things. Now you can't be uncertain about the safety and
the adequacy, but you're not going to be 100 percent certain.
DR. GARRICK: Of course, they're not 100 percent certain
about any application on any licensee they have.
MR. FERTEL: That's right. That's right, but none of the
applications we have today, John, go out beyond 40 years. So it's a
very finite thing, it's a very controlled situation, it's a phenomenon
that I understand or at least I can portray pretty well whether it's a
powerplant or a fuels facility.
This is something that it's very hard to explain to folks.
It sounds outrageous that we, you know, have the audacity to think we
know what's going to happen in 10,000 years or a million years. So I
think that part of the challenge when we take the risk, when you have a
dialog on how we do this in risk space, is to recognize that it's not
like if you make your decision in 2004 you've got to then sit down and
go to church every day and pray you were right because oh, my God, it's
going to -- the next day this thing gets operational and the world ends.
That's not true. There is at least 50 years of loading. And then there
is a couple hundred years of verification. Not that anybody wants to
find out they're wrong at that point, but --
DR. GARRICK: That brings up something that's getting a lot
of discussion now that I'd be curious if industry has an opinion about,
and that's the issue of the operating period or the preclosure period, I
should say. We're now hearing different numbers, like possibly a
300-year period for keeping the repository open.
MR. FERTEL: We heard -- I think Lake Barrett mentioned 300
years two years ago at our fuel cycle conference down in Savannah or
Atlanta. And I can't say that as an industry we've sat down and said
that we think 100, 200, 300, or 500 is right. As an individual, when he
said that, that made some sense to me only because it seemed to be
something that most people could somehow relate to a lot better than
10,000 or a million.
And whether or not 300 is more than you need to get, you
know, the verifications that you need or less than you need, whether or
not we're going to determine that global climate change is such a threat
to the human race and the planet that a greater use of nuclear worldwide
is important, and as such you really do need to reuse this fuel in some
way and you need to have access to it, I don't know, but 300 doesn't
sound terrible to me. It makes a helluva lot more sense than saying I'm
going to shut it up in 50 years or 100 years and it's going to be okay
for the millennium, forever. So my personal reaction is that's not bad.
Now if they said 250, I'm not sure I'd quibble that that's a big
difference.
DR. FAIRHURST: Why do you see such a significant difference
then between 100 and 300?
MR. KRAFT: I don't think we do.
MR. FERTEL: Again, I don't think I do. I don't think I do.
MR. KRAFT: I think, though, it's a decision that if you do
the repository right in accordance with current-day regulations and then
you create a confirmatory testing program after 100 years let our
great-grandchildren decide what they want to do.
DR. FAIRHURST: Fine. I agree with that.
MR. KRAFT: And that's fine. There was a report DOE did,
Tom Isaacs and Max Blanchard did a couple years ago, that spoke to this
issue, and it was largely ignored for a long time. But it's an
excellent piece of philosophical work that talks to this question
exactly, that what we owe future generations is the ability to dispose.
The material may prove to be extremely valuable, and they would want it
back, or they may learn something over the next couple of hundred years
about geology that we don't know. They may write the perfect saturated
zone flow model that we can't write now. Who knows. So let them make
the decisions then.
DR. FAIRHURST: Let me give you another perspective. There
was a recent international conference on retrievability, and that was
the first time the rest of the world found out the U.S. had moved to a
suggestion of 300 years. And there wasn't another country in the world
that had thought to go beyond 100, and they thought the U.S. was
defending the fact that institutional controls would disappear after 100
years, and therefore you didn't have any right to plan beyond 100 years.
And their view, which I think is quite a good one, is that they thought
that the U.S. was crazy to think that institutional controls would
disappear in 100 years. And then they saw what happened to control of
nuclear materials in Russia.
MR. FERTEL: Well, what control of nuclear materials in
Russia?
DR. FAIRHURST: Because at that time if you listen to the
Swiss and the Swedes and so on they were saying 300 years was reasonably
fine to go and the U.S. was being overly pessimistic with 100 years.
Now they're not even sure that individual countries that exist today in
Europe, such as Germany and France, will remain as Germany and France in
300 years. So they have no idea of how to maintain political
institutions for any length of time. Look what's happening in
Yugoslavia and so on right now. So they feel -- they are becoming very
comfortable with the notion that the U.S. had it right the first time
and then found out the U.S. had come and said we're going to change it.
MR. FERTEL: I think the issues they're raising go far
beyond whether we have it right for disposal of nuclear waste, to be
honest with you.
DR. FAIRHURST: But what I'm saying is if there are good
technical reasons for doing it, yes, but I have not heard the technical
reasons for doing it.
DR. GARRICK: Do you mean to go from 100 to 300?
DR. FAIRHURST: Yes. I mean, there are some significant
problems in going to 300 years.
DR. GARRICK: I'm not sure industry is really aware of
those.
DR. FAIRHURST: Well, I mean, you're just keeping those
tunnels open.
MR. KRAFT: You mean keeping the tunnels open for 300 years.
Oh, well, again, again --
DR. FAIRHURST: But these are not trivial, and if --
MR. KRAFT: Dr. Fairhurst, absolutely not. But I think, and
in that regard, WIPP has a greater problem, because those tunnels will
not remain open any significant amount of time like that, so --
DR. FAIRHURST: WIPP has it right, because you want them to
close.
MR. KRAFT: It's a different design, I agree completely.
But my point is that all the sciences evolve, as will underground
tunneling, as everything evolves over that period of time. And so in
100 years our great-grandchildren will be a whole lot smarter and a
whole lot richer than we are, and they will decide what to do.
MR. FERTEL: We hope.
DR. GARRICK: Yes. Give your name, et cetera.
MR. HAMDAN: My name is Latif Hamdan. I'm with NRC. And I
just want to comment on something that Marvin mentioned about the
licensing -- the licensee-regulator relationship between DOE and NRC.
And while this transition may be difficult, as you say, I just want to
point out that this is not going to be a first, because DOE is a general
licensee for like two dozen 11E2 mill tailing sites already, and then
so -- will be just maybe not a general license but this is not the first
time that it's going to happen.
DR. GARRICK: Thank you.
MR. FERTEL: John, those were only -- those were the
comments that we were planning on making today, but we certainly welcome
the opportunity to talk about any of the issues or answer any other
questions that you all have.
DR. GARRICK: Well, we are certainly interested in what
industry thinks are the primary problems that lie ahead to get this
licensed, and, you know, we've been talking about them when we've talked
about design and QA and the preclosure operating period and what have
you.
Are there any other issues of that nature that --
MR. FERTEL: Well, I think when we think about licensing
right now, you've hit them. What the standard is probably is the key
issue, what are we trying to meet as far as the radiation standard, of
making sure that the license submittal is adequate requires the QA
program to be really put together correctly, making sure the application
is complete and deals with, and we think that the preclosure issues
really do need to be addressed maybe a little bit more than DOE has been
giving thought to them.
Understanding how we are going to make the final decision on
risk, as far as satisfying the standard, in probabilistic space, we
think is a bit of a challenge, even though it is only way to do it for
this. I am interested in Charles' comment on the 300 years. I am not
sure the U.S. policy has changed to 300 years, to be honest with you.
DR. FAIRHURST: No, it hasn't.
MR. FERTEL: I think there is a lot of trial balloons that
are being sent up to see what people think.
DR. FAIRHURST: Yes, fire up the balloons.
MR. FERTEL: So, I mean right now, those are the issues,
and, again, I appreciate that under UMTRA and other places, DOE is a
licensee. We think that maintaining the licensing relationship between
DOE and NRC, and particularly the longevity that is going to be required
for this, is something that really does require stability and good
up-front planning. That is just from our own experience.
MR. KRAFT: I think, though, that DOE's transition in OCRWM,
and also broadly in DOE as they go to external regulation, the way DOE
has functioned internally as their own regulator has been one more of
negotiation than it has been of adjudication. That is a very different
world, because when your internal regulator and your internal doer have
the same agency goal in mind, there is a lot of desire to work it out
and get to the same place, meet the requirements on the way.
NRC doesn't have that same organizational goal, and I think
-- that doesn't make it any easier or harder, it makes it different, and
DOE doesn't know how to do that yet, and that is something they have to
learn how to do, there is evidence in the conversion of their lab sites
to external regulation, where they are having exactly the same cultural
issues. And I think that is where are seeing some of the problems.
That is where the QA issue is coming from. It all stems from that, from
a different way of doing business internally.
By the way, I should say, they recognize it. We have spent
a lot of time with them. They recognize it. What they are not sure
about is how to correct it, and how to put certain processes in place to
make sure that internally they are getting it right.
DR. GARRICK: Yeah, it is an interesting problem. I still
am heavily involved in the nuclear power game, and like to play the game
at every nuclear power plant I go to of asking different people, whether
they be maintenance, operations, engineering, or technical support, what
has been the most difficult adjustment for them to make in working at a
nuclear power plant? Especially new people. And almost without
exception, the answer that comes back is to be willing to be totally
accountable and to be watched in everything you do. You know, even the
maintenance actions are watched.
And I think that might be the key to the underlying cultural
change that would -- that might be the most difficult, especially for
technical people, or especially for people that have worked in a
security environment for decades. I think that might be the most
difficult adjustment to make, is to be willing to share what you are
doing, the calculations that you make, the decisions that you make, the
reports that you write, in a completely open and accountable manner.
My database says if I had to point to one thing that would
be -- that would contribute most to DOE making that transition, it would
be to develop that kind of state of mind.
MR. FERTEL: To be honest, John, I think the effort by the
NRC staff and the DOE staff working cooperatively over the last four or
five years has probably helped move them down that road better than if
they were starting fresh, because I think that there has been a lot of
openness, at least at the meetings that I have been able to attend and
listen to the discussion. And maybe even the fact that everybody is
going to Internet web sites to put everything out is going to sort of
foster the same kind of openness, because people put things up and it
just becomes second nature to do it, which may help. Because I think
you are right, that is a challenge in dealing anywhere in the DOE
system.
DR. GARRICK: Right.
MR. FERTEL: And it is just a very different and almost a
closed culture because of the weapons background.
DR. GARRICK: You see that in other agencies, too. This has
been one of the most difficult transitions for NASA to make, is to be
increasingly accountable and open in all of their activities from design
and analysis to flight readiness reviews. And, of course, the Rogers
Commission study revealed that one of the problems they had was that
this openness didn't exist, especially between management and
engineering with respect to certain technical issues.
So, you know, if we had to -- if industry had to push a few
buttons as far as helping DOE is concerned, I think the whole mindset of
being willing to share and being willing to let people look at your
calculations and peer review everything that you do would be a major
start in the right direction.
Yes, sir?
DR. STEINDLER: I don't want to give you the impression that
the Department of Energy walks on water, but let me simply point out
that the Department of Energy has run quite successfully a very large
number of reactors and sundry other facilities for some 50 years. The
general notion that the Department is not regulated and therefore
doesn't know how to do this simply misses the point of a Secretary of
Energy named Watkins who, coming from the Navy, instituted a regime of
activities which probably are about as close to internal regulation as
you are likely to get and accountability is in fact in the Department.
To an outside semi-independent agency they all happen to be
Government employees. That is about where it stops on a practical
basis.
You know, I don't want to go through this litany of things
that the Department doesn't know how to do, and Heaven knows there are a
lot of things the Department doesn't know how to do, but I don't think
we want to paint a picture of a totally incompetent bunch of folks who
are largely scientists who can't give you a straight answer yes or no
when questioned on the stand -- which may be true in part, since we are
all two-handed scientists, but, you know, I have serious difficulties
when somebody says the Department doesn't know how to do QA and
therefore industry, that runs reactors and some processing facilities,
is the outfit that is going to teach them how to do that. I don't think
that is quite the way it is going to work because I think that the
Department has a fairly good idea of what the issues are, number one,
and the QA issues that are currently plaguing DOE are not the same as
those you find in operating reactors.
That is not where the issues are. The issues are laboratory
and technology development and industry doesn't have a hammer-lock on
that.
Let me make one other question to the speakers. You
indicated that H.R. 45 looks like it has a fairly decent attribute to
it, and you liked the 100 millirem -- I guess it is millirem per year
figure.
You surely are aware that that violates the ICRP regulations
for reducing the total dose by some factor, usually three, which gets
you down to the 33 or 25 millirem which is where we really are.
Why is it that you think 100 millirem is that great?
MR. FERTEL: Again, let me take a couple of the comments
that you made but let me stop at the one you just asked.
What I said, and I think it is consistent with what Chairman
Jackson said, is that we think the standard ought to be 100 millirem.
We think you ought to strive to go -- and I am not sure I have problem
with striving for the 25 millirem that Part 63 has -- but we don't see a
reason that you wouldn't have 100 millirem as an acceptable standard at
a site where there were no other sources of radiation that you are
protecting against and it is a unique standard to the Yucca Mountain
site, so again we don't see a problem with that, but I am not saying
that I would say that you have got to go to to 100 millirem is the test
that you are going to meet.
We don't do that at power plants. We go down to as low as
reasonably achievable.
On the comments on DOE, everybody has their own perspective
on DOE and I don't want to talk about the entire DOE. We were talking
about OCRWM and I haven't said anything here I haven't said to Lake
Barrett, and the QA problems that they have on OCRWM relate to
laboratories and USGS and other places, and at power plants you have
problems with managing contractors and builders and other guys. QA is
not a terribly difficult science but it is a terribly difficult
experience to learn.
In our industry we have learned the hard way. We have had
projects that have spent up to $500 million reconstructing their design
basis so that they could get an operating license, okay, because we
didn't manage the paperwork right because we had people who didn't think
they had to do the paperwork. The construction was fine.
This is the issue, one of the issues you have, so the
experience the industry has is directly relevant even though it was a
power plant versus a repository scientific study, so I think it is
totally relevant and I don't think, and I have spent time in the DOE
complex, that the QA culture within the DOE complex is anywhere near the
QA culture that the industry has developed through hard times learning
ourselves, so we can disagree on that but I have no problem in the help
that we could try and provide them.
As far as the regulation, our comment on regulation relates
to the fact that DOE has never been a licensee. That is the term I
continue to use. That is a lot different than either what I think John
Conway on the Defense Nuclear Facility Safety Board does, which is
excellent work -- I think they do a good job. It is a lot different
than what ES&H does. I have spent time at the DOE complex. It is very
different to be self-regulated.
I was there doing things when Admiral Watkins sent his tiger
teams out. They did some good, they did some bad. They didn't improve
a lot in certain places. They shook up a lot of things. They didn't
change a lot of things at times, and so our comments relate to a
licensee's role and a regulator's role and the Department outside of
some of the mill tailing sites, the Hanford tank farms, and a couple of
other places have not played that role. They don't have that experience
and when you talk to their people they are good people, they are smart
people but it is experience you have to gain as a licensee.
Power plant guys that weren't licensees didn't do well until
they got people that were experienced. It is the nature of the beast.
You have to learn how to play the role that you play in this particular
game, which is a regulator-licensee game -- so it is not a damnation of
the Department. I think they do a lot of things that are good, but
there's areas where from our standpoint they need some help.
I mean if this program was running smooth they would be
taking our waste last year, so it is hard for us to sit here and say we
have got tremendous confidence, everything is great, because right now
they are telling us 2010 and we don't believe 2010 is real.
We don't believe it. We think they need a lot of help to
come close to 2010.
DR. GARRICK: I don't know why I have this feeling, but I
feel I need to respond to Marty.
[Laughter.]
DR. STEINDLER: I can't understand why. I didn't really
want to carry this on much past a quarter to 5:00.
DR. GARRICK: We are not going to carry it very much
further, but to recapitulate what I was saying was from an industry
perspective that it seems that industry after a lot of trial and error
has kind of learned how to do it and that they -- while maybe they have
only learned how to do QA in recent years they have been under a
regulatory environment for a lot longer period of time and the
combination of those two things seem to me to be an important resource
for DOE to consider, given that they have never been under a regulatory
environment of the type we are talking about here and are about to do
so.
The other thing is I agree with you because I was part of
that process that the laboratories have done some remarkable things and
we have had many war stories about things that we have done early in our
career that we could never do now. And so the change isn't always
better. We could make changes in operations and design that now would,
in many cases, not be timely by the time we complied with the DOE orders
and all of the regulatory requirements.
But I have also served on oversight at national labs and for
nuclear power plants, and from that perspective, based on the evidence
that I saw from that perspective, it was clear to me that the process of
implementing a regulatory activity had matured a great deal in the
nuclear power industry. I made the point earlier that for the first
time U.S. nuclear power plants are finding themselves in the top 10 of
world performers. It used to never happen. It used to always be Swiss
plants, Japanese plants and French plants, but no so now. Even the most
famous reactor name in this country, namely TMI, is now one of the best
performers in the world year-in and year-out. And one of the reasons
they are one of the best performers in the world is they have a
magnificent, in my opinion, QA program, and nuclear assessment activity.
And so all I am suggesting is that, as painful as it has
been for them to make their transition, and we all know about the pain
that took place there, they have made it. And we ought to take
advantage of that as much as possible.
MR. KRAFT: One last item. I am not going to talk about QA,
that is -- thank you. You asked other problems that stand in the way.
DR. GARRICK: Yes.
MR. KRAFT: A non-regulatory related problem that affects
both agencies is money. We pay in, as an industry, our rate-payers,
$600 to $630 million a year. Congress appropriates less than a third.
DR. GARRICK: And now you are going to sue them and they are
going to pay you back, you are going to pay for the suits with your own
money.
MR. KRAFT: Well, now, you know, that is an interesting
question. The Justice Department attorney --
DR. STEINDLER: That is hardly likely and you know it.
MR. KRAFT: The Justice Department attorney who appeared
before Congressman Barton the other day said that they were still
studying the issue, which I think is Justice Department speak for we are
having a hell of a fight internally to figure out how we are going to do
this.
The Court of Appeals, which directed us back to the Court of
Claims, in essence, did open the door and said that there is a
possibility that what they may decide to do will in itself be illegal,
so, you know, come on back. So these are issues that are not settled.
But you are right, if they do end up finally paying damages
out of the waste fund, that is another pressure on the waste fund. But
my point is that the Congress, because of its internal procedures, has
difficulty funding the program at the level the program needs to be
funded at this point. And if you look at the total system life cycle
cost estimate that accompanies the Viability Assessment, forget H.R. 45,
the current program cannot be funded on the current funding profile.
The amount of money needed to hit 2010 using the current funding
profiles that they are assuming in the future of the current
Presidential budget is not sufficient to run this program, to meet 2010.
So you have got four threats on 2010. You have got money,
you have got their licensing ability, their internal QA program and an
EPA standard. Those are the four threats to us that make 2010 a
questionable date.
MR. FERTEL: In probabilistic space, it is a low
probability, 2010 date, in our minds, because of those four reasons.
DR. GARRICK: Yes. Any other comments or questions?
Charles? Ray? George? Marty?
DR. STEINDLER: It is two minutes to 5:00.
DR. GARRICK: Staff?
[No response.]
DR. GARRICK: We appreciate your coming by and talking to
us.
MR. FERTEL: Thank you.
MR. KRAFT: Thank you.
DR. GARRICK: We like to hear from you. All right. We can
go off the record now.
[Whereupon, at 4:59 p.m., the meeting was concluded.]
