Advisory Committee on Nuclear Waste 133rd Meeting, March 21, 2002
Official Transcript of Proceedings
NUCLEAR REGULATORY COMMISSION
Title: Advisory Committee on Nuclear Waste
133rd Meeting
Docket Number: (not applicable)
Location: Rockville, Maryland
Date: Thursday, March 21, 2002
Work Order No.: NRC-283 Pages 185-321
NEAL R. GROSS AND CO., INC.
Court Reporters and Transcribers
1323 Rhode Island Avenue, N.W.
Washington, D.C. 20005
(202) 234-4433. UNITED STATES OF AMERICA
NUCLEAR REGULATORY COMMISSION
+ + + + +
ADVISORY COMMITTEE ON NUCLEAR WASTE
(ACNW)
+ + + + +
133RD MEETING
+ + + + +
THURSDAY,
MARCH 21, 2002
+ + + + +
ROCKVILLE, MARYLAND
+ + + + +
The subcommittee met at the Nuclear
Regulatory Commission, Two White Flint North,
Room T2B3, 11545 Rockville Pike, at 8:30 a.m.,
George M. Hornberger, Chairman, presiding.
COMMITTEE MEMBERS PRESENT:
GEORGE M. HORNBERGER Chairman
RAYMOND G. WYMER Vice Chairman
B. JOHN GARRICK Member
MILTON N. LEVENSON Member
STAFF PRESENT:
JOHN T. LARKINS, Executive Director
SHER BAHADUR, Associate Director
HOWARD J. LARSON, Special Assistant
LYNN DEERING
LATIF HAMDAN
CAROL A. HARRIS
MICHAEL LEE
RICHARD K. MAJOR
I-N-D-E-X
AGENDA ITEM PAGE
Opening Statement by the ACNW Chairman . . . . . 188
Yucca Mountain Review Plan, Revision 2
Presentations:
Jeff Ciocco . . . . . . . . . . . . . . . . 189
Banad Jagannath . . . . . . . . . . . . . . 205
Tim McCartin. . . . . . . . . . . . . . . . 211
Pat Mackin. . . . . . . . . . . . . . . . . 258
Jeff Pohle. . . . . . . . . . . . . . . . . 273
P-R-O-C-E-E-D-I-N-G-S
(8:36 a.m.)
CHAIRMAN HORNBERGER: The meeting will
come to order. This is the third day of the 133rd
meeting of the Advisory Committee on Nuclear Waste.
My name is George Hornberger, Chairman of
the ACNW. The other members of the committee present
are: Raymond Wymer, Vice Chairman; John Garrick; and
Milton Levenson.
Today the committee will: 1) hear a
presentation from the NRC staff on Revision 2 to the
Yucca Mountain review plan, and 2) continue
preparation of reports.
Richard K. Major is the designated federal
official for today's initial session. This meeting is
being conducted in accordance with the provisions of
the Federal Advisory Committee Act.
We have received no written comments or
requests for time to make oral statements from members
of the public regarding today's sessions. Should
anyone wish to address the committee, please make your
wishes known to one of the committee staff.
It is requested that the speakers use one
of the microphones, identify themselves, and speak
with sufficient clarity and volume so that they can be
readily heard.
Let me get to my Thursday page. Today we
are going to -- this morning we're going to have our
long-awaited briefing on the Yucca Mountain review
plan, and the Yucca Mountain review plan is quite
important to the committee. It's obviously an
important step for the NRC in preparing to review a
potential or possible license application.
And I know we've talked offline with Jeff
Ciocco, and we know that staff has been making lots of
progress, and we're looking forward this morning to
getting our first official briefing. And I understand
that this is going to involve four or half a dozen
people, and, Jeff, I'll let you introduce yourself,
and you can orchestrate the dog and pony show.
MR. CIOCCO: Very good. Thank you, and
good morning. My name is Jeff Ciocco. I'm the
project manager responsible for the development of the
Yucca Mountain review plan. Before I get into my part
of the presentation, just let me tell you what we're
going to cover this morning.
We're going to cover -- we're going to do
an introductory presentation. We're going to have a
presentation on the repository safety prior to
permanent closure, and that's our preclosure. And
that is -- Banad Jagannath over there is going to
present it. We've got a postclosure presentation by
Tim McCartin.
We have performance confirmation and a
research and development program to resolve safety
questions by Pat Mackin. And then we have a brief
presentation on the quality assurance.
Let me tell you some of the materials that
we put up in the back of the room, as well as on your
deck. You got a briefing packet which contains all
five presentations. We'll go through it, and we can
orient you.
I also put back there a copy of the press
release dated March 4th of this year, which the
Commission announced a release of public availability
of the Yucca Mountain review plan, as well as hard
copies of the actual plan back there. There are
several on the floor, and that's the same version
which is up on the website right now.
I also want to say that the development of
the Yucca Mountain review plan -- you're going to hear
about five presenters here this morning. However,
this is really a team effort from the Division of
Waste Management as well as experts from the Fuel
Cycle Safety and Safeguards Group, who wrote the
emergency planning, physical protection, and the
material control and accountability.
And we have staff here at the NRC, as well
as our counterparts at the center in San Antonio. So
this was really a team effort, and Pat Mackin is the
co-project manager from San Antonio. But it's really
the staff who put the pen to the paper, and then in
many -- at many times they also pointed at Pat and I.
But, really, what you're going to hear
today is presentations from the primary authors and
those people responsible, but there is a whole slew of
cast.
So let me go ahead and start the
introduction.
MEMBER GARRICK: Are you saying it's
really their fault?
(Laughter.)
MR. CIOCCO: No. I'm really the YMRP
apologist, so I'll take responsibility.
As far as the briefing agenda this
morning, for the introduction, I'll go through the
status and structure of the review plan, what our
philosophy was in its development, how the YMRP will
change, it's going to be a living document, and the
different types of reviews.
We're going to conduct an acceptance
review, a review for general information, and the
administrative program requirements, as well as a
little bit about what the step-wise licensing approach
is in Part 63 and how that is covered under the Yucca
Mountain review plan.
Here is the status of the Yucca Mountain
review plan. We last briefed you back in March of
2000. At that time, I think we gave you an overall
outline of the Yucca Mountain review plan. It was
currently under development. The Yucca Mountain
review plan draft Revision 1 was made public for
information only back in November of last year.
It wasn't consistent with the final Yucca
Mountain regulations, and that was sort of an
unauthorized release of the Yucca Mountain review
plan. So the Commission decided to make it publicly
available.
Right now, we're at the Revision 2. It's
a draft report for comment. It's currently available
on the NRC's public website, and there are copies
provided in the back of the room as well. There will
be a NUREG released by the end of March, followed by
a Federal Register notice and request for public
comments.
Now, some of the members here have
received the actual NUREG. It's just coming off the
press right now, and there is about 1,300 copies being
shipped. If you're on the mailing list, if you're on
any kind of list, chances are you're going to receive
the actual NUREG and it looks like this.
It's identical in page numbers to what's
in the back of the room here, and there's also
instructions in there. You can contact me or contact
distribution here and get a copy of it.
Here's the structure of the review plan,
and we're going to go through some of this today. But
it's basically set up -- Chapter 1 is the
introduction. Chapter 2 is an acceptance review.
Chapter 3 is the review plan for general information.
And Chapter 4 is the review plan for the safety
analysis report. And this is structured according to
Part 63, Section 21, which is the content of the
license application.
Really, the acceptance review is for
docketing, and the review plan for general information
in 63.21 is Section B, and it contains the elements of
a general site description, proposed schedule for the
construction, the physical protection plan, material
control and accountability, and description of the
site characterization work.
And the safety analysis report, which is
63.21 in Part C, contains several sections. One is
the preclosure repository safety before permanent
closure. You'll see postclosure as the repository
safety after permanent closure, the research and
development program to resolve safety questions -- and
these three will be covered today, as well as
performance confirmation. And then the very last
section is the administrative and programmatic
requirements. And then we just have tiered down what
the different sections are for preclosure and
postclosure.
As far as each of the sections of the
Yucca Mountain review plan, they're really consistent
if you're familiar with other standard reviews plans,
whether for Part 70 for licensing of spent nuclear
fuel, the MOX facility, they're all basically
structured the same. They've got the areas of review,
which are the topical areas, and the scope of the
review. It's got the review methods. Really, it's
for the staff to use. They're step-by-step
procedures.
And the level of detail and complexity of
the review methods are determined by the requirements
and the nature of the technical issues. You'll see a
lot more in the review methods in postclosure and
preclosure than you will see for the areas of general
information.
It contains acceptance criteria, which
defines what is an acceptable compliance
demonstration. And the acceptance criteria in the
review plan are based on regulatory guides and the
requirements of the rule, any codes or standards, and
the results of staff investigations.
We've been doing prelicensing interaction
for over 15 years, and a lot of the criteria are what
were developed in the issue resolution status reports,
the IRS ARBs. And then there's the evaluation
findings section, which is the examples of the -- or
it does contain examples of the general findings
suitable for a safety evaluation report, and then it
contains references. And this is standard throughout
the review plan for all of the sections.
A little bit of the regulatory philosophy
in setting up the review plan. We received a lot of
guidance from the Commission, as well as management.
The licensing review philosophy for the NRC, we did
not select the sites or designs. The NRC reviews are
comprehensive. We will cover every section of
Part 63.21 in a license application. We will focus on
areas most important to safety or waste isolation in
those reviews.
NRC defends its licensing decisions. It's
up to DOE to defend its own safety case. We have to
look for reasonable assurance, and that's in
preclosure area, and reasonable expectation, and
that's postclosure, of compliance.
The Yucca Mountain review plan implements
Part 63, which is the risk-informed, performance-
based, site-specific rule. And it incorporates more
than 15 years of staff knowledge, and it doesn't
contain prescriptive acceptance criteria.
The subsequent presenters are going to
cover the different aspects in their particular areas,
get into how that's risk-informed and performance-
based.
We'll continue along with the regulatory
philosophy. The general review process, if there is
a license application for Yucca Mountain, and
prescribed in the review plan, will conduct an
acceptance review for docketing. It's a 90-day
review. If it's docketed, we'll conduct a detailed
technical review, prepare a safety evaluation report,
and then, if necessary, we will develop a request for
additional information.
That could also happen in the acceptance
review. There could be requests for additional
information in the acceptance review. This is
standard NRC licensing.
CHAIRMAN HORNBERGER: Does that change the
90 days, if you request additional information in the
acceptance review?
MR. CIOCCO: Yes, I think it does have --
yes, if there is additional time needed.
The use of the risk-informed, performance-
based measures, this is just kind of an overview.
We'll get into more detail in each of the areas. But
the review methods and the acceptance criteria are
focused on assessing compliance with the performance
objectives in Part 63.
The postclosure safety, a separate section
for the areas that the staff has determined to be most
important to waste isolation -- and this results from
the key technical issues, from the issue resolution
status reports, and the more than 15 years of
prelicensing.
The acceptance criteria are flexible
rather than prescriptive. DOE always has the option
of not using the Yucca Mountain review plan, but they
must defend a safety case. DOE must select compliance
demonstration methods, show they are appropriate, and
use them properly in their safety case.
We do a lot of cross referencing between
the sections of the review plan, and it was also
written to address any step of licensing -- and I've
got a couple of slides later on that will explain the
different step-wise licensing approaches in Part 63
and how the Yucca Mountain review plan will
accommodate that.
YMRP is a living document and will change.
Revision 2 is a draft report for comment. We will
seek public comment in the ACNW review. I expect
after this NUREG 1804 completes its distribution we'll
issue a Federal Register notice and then seek a 90-day
public comment period. And we're also going to have
public meetings in and around Las Vegas during the
public comment period to get their feedback.
NRC staff will incorporate the comments as
appropriate, and we will provide the revised document
back to the Commission. This is how the document
would change in light of the September 11th terrorist
attacks, that the Commission has directed the staff to
conduct a comprehensive evaluation of our physical
protection programs. If these efforts indicate NRC
regulations need revision, we'll go through the
appropriate method and that could dictate a change to
the Yucca Mountain review plan.
It could also change because of the multi-
step licensing process, and Part 63 also provides
opportunities for us to revise the Yucca Mountain
review plan.
An acceptance review -- the first step in
the review -- it's the first screening of DOE's
license application using the acceptance checklist,
which is based on 63.21. It's a checklist that goes
through all of the general information. There's I
think five or six sections, as well as the 14 or 15
sections of the safety analysis report. And this is
all under Chapter 2 of the Yucca Mountain review plan.
It determines completeness of the
information, that the information must be sufficient
to permit a safety review, 90 days are allowed, and
the results of this we either accept for review and
docketing, we accept but request additional
information, or we reject because there's inadequate
information to support a detailed safety evaluation
report.
Now we're getting into Chapter 3 of the
Yucca Mountain review plan. It's the review for
general information. It examines the overview
information for the site and design, and a lot of
these aren't detailed technical reviews either. There
is a general description of the site. There are
proposed schedules for construction, receipt, and
emplacement of waste, which isn't a technical review,
because this information is really reviewed in detail
back in preclosure and postclosure sections of the
Yucca Mountain review plan. It's just general
information.
The physical protection requirements --
and Part 63 refers up to the safeguards section of
Part 73, material control and accountability, which is
I think found under Part 72, which is independent
spent fuel and high-level waste investigations, as
well as a description of the site characterization
work. Once again, most of these aren't detailed
reviews.
Now, this is Section 4.5, the very last
section of the Yucca Mountain review plan. It's to
review for administrative and programmatic
requirements. It includes a lot of operational
requirements. This is where you'll find the quality
assurance, expert elicitation, emergency planning, and
there's a whole list here.
And none of these have any performance
objectives in Part 63. We use existing NRC programs
and look for opportunities to modify any kind of
prescriptive criteria. For instance, the emergency
planning, we use what's -- I guess it's in I think
Part 72 as well in this section.
As far as a multi-step licensing approach,
it's important to understand that the Yucca Mountain
review plan is going to be used if there is an
issuance of a construction authorization. Following
that could be a license to receive and possess. So
Part 63 allows for well-defined steps in licensing
with incremental decision points that allow for
continual learning and progressive confidence.
Three steps in licensing -- maybe it's
four -- there is also license for termination. But
the first step under 63.31 is the construction
authorization, which is based on the site
characterization results -- is the reasonable
assurance and the reasonable expectation that waste
can be disposed at no unreasonable risk to health and
safety of the public.
The second step would be the license to
receive and possess, 63.41, which is informed after
construction activity, and it's really based on, are
the underground systems for initial operation
substantially complete?
And then you have the amendment for a
permanent closure in 63.51, which is updated by
information to the license to receive and possess. It
has information from the performance confirmation,
data obtained from the operational experience, and
then 63.52, which I didn't leave here, I think is the
license for termination. So it's a three- or four-
step, depending on how you look at it.
CHAIRMAN HORNBERGER: Jeff, the words
there post-permanent closure monitoring program, so
there is a provision for monitoring in perpetuity or
something?
MR. CIOCCO: Yes. In 63.51, I think they
have to describe what long-term monitoring program
they will have, whenever there is an amendment for
permanent closure.
MEMBER GARRICK: What do you mean by
informed by construction activity, etcetera?
MR. CIOCCO: That is -- for the updated
license application, informed means they need to
include data obtained during construction, performance
confirmation, whenever they update their performance
assessment at this stage. So it's informed from
information that was gained along the construction
authorization. They still need to -- they need to
demonstrate performance compliance.
So this is how the Yucca Mountain review
plan -- staff intends to use the review plan to
conduct reviews of the potential application with
respect to construction authorization, license to
receive and possess. Although there are some
differences in the requirements for construction
authorization and the license to receive and possess,
they are really very similar to where we can use the
evaluation of findings for both cases.
Accordingly, the evaluation of findings
contained -- they were prepared to be suitable for
both reviews. It's reasonable to expect that we would
have revisions if there was a construction
authorization. As we learn as we go along, we may --
you know, we may revise the Yucca Mountain review plan
after that.
And this is just kind of a side note, but
at the time of the review, if there is a construction
authorization, several aspects are really based on a
commitment by DOE rather than hard evidence, such as
the training program, material control and
accountability, personal qualifications. But at this
point, they're just in construction. They don't have
their personnel on board yet. They are really not
implementing their plan yet.
So that was -- that's it for the
introduction. It was kind of just meant to be an
overview of the content of the review plan, how it's
going to be utilized. Next, we'll get into the
preclosure, and then postclosure.
Do you have any questions on the
introductory material?
CHAIRMAN HORNBERGER: Does anybody have
any questions on the general overview? No?
MEMBER LEVENSON: The page numbers for the
committee members -- the page numbers in the bound
copy are not the same as in the hard copy we received
previously. So if you have comments from pages, they
are --
MR. CIOCCO: Yes. I'm not sure what
version you received earlier.
MEMBER LEVENSON: It's draft Revision 2.
MR. CIOCCO: Yes. That may be one that I
gave you. Yes. I checked this morning -- well, the
ones that are back here, the ones we printed off the
internet, they were the same page numbers.
MEMBER LEVENSON: I checked what was lain
in front of me this morning, and it was --
MR. CIOCCO: Okay. Well, whatever I can
do to facilitate your review, we will certainly do
that.
Okay. Next, I'll introduce Banad, who is
going to do the preclosure.
CHAIRMAN HORNBERGER: Jeff, I had I guess
one quick question. Particularly I guess in -- it
struck me when I looked at your list for the review
for administrative and programmatic requirements. A
lot of that information you will have vetted prior to
a license application, right? And I think of things
like expert elicitation.
MR. CIOCCO: Right. Yes, absolutely. I
didn't -- I wasn't trying to imply that all of the
sections are a commitment. A lot of that information
we'll have, right, for the safety evaluation report.
MR. JAGANNATH: Good morning. I am Banad
Jagannath. I will briefly present the preclosure part
of the Yucca Mountain review plan.
My outline basically contains organization
of preclosure safety assessment review, and then how
-- the risk-informed, performance-based aspect of it.
10 CFR 63.21(c)(5) requires the performance of
preclosure safety analysis of the repository
operations area prior to permanent closure.
If you look at the big chart Jeff put out,
the preclosure area contains one preclosure safety
assessment plus another block for retrieval
operations, another block for dismantlement,
decommission, and decontamination activities. These
are three distinct components of the preclosure
requirement. Our main focus will be on the preclosure
safety assessment.
Preclosure safety assessment is defined as
a systematic examination of the site design, the
potential hazards, consequences, initiating events,
and the potential dose resulting from the
consequences. Systematic consideration of all these
things in arriving at the decision in terms of
performance components.
Part 63 is a dose-based rule, in that the
licensee is supposed to demonstrate compliance with
the performance objectives, permissible doses to
workers and the public.
Following the logic of the definition in
the preclosure safety assessment, this is how the
review plan is arranged. It's like a sequence of
evaluations you go through, what I would define a
conclusion. Basically, the first piece, chapter on
site description as it pertains to safety analysis.
This chapter has all of the site information, starting
from geology, hydrology, rock, seismology, all those
things.
The information presented and the
evaluation will be as appropriate for future
evaluations. This provides an input for the safety
analysis.
The second section is a description of
structure, systems, components, equipment, and
operation of process activities. This is the design
information you need to be able to use the site
information and design information for the evaluations
in the safety assessment.
Again, depending on how it is used, the
information should be enough for the staff to
understand what's being done there and be able to come
up with -- make further safety evaluations. Some
areas there will be more details. Some areas there
will be less details. But it's dependent on the topic
of the structures.
The next one is hazardous items,
additional hazards, and the initiating events. These
are both natural and human hazards. These are under
external and internal. These are all considered
initiating events.
Then, comes the chapter on event
sequences. But considering the initiating events,
then the operations of the facility and the facility
descriptions, you come up with the initiating event
that would ultimately pose a radiation exposure dose.
And at the end of the initiating event
sequences, you have possibility for any event
sequence, a frequency at which it will occur. And
based on the scenario at which it ends up, you will
have in the next section a talk on the consequences.
You evaluate the consequences, which are -- it goes to
public and workers.
And this dose is the one that we use in
demonstrating compliance with the performance
objectives. And then these are I guess the numerical
radiation limits in the 10 CFR 63, and also these are
the -- field doses are for Category 1 and Category 2
event sequences. That's what you'll find out.
This is the demonstration and compliance
in terms of dose as it is -- part of this analysis
will be a combination of event sequences, and the dose
is identification of structure, systems, components.
The next section is the one --
identification of structure, system, components
important to safety, and safety controls and measures.
This comes out of the information from the event
sequences and the dose consequences. A combination of
these two will identify what are the important
structure, systems, and components.
MEMBER LEVENSON: Excuse me. I have a
question about that last bullet -- by experience, and
historically we know what important to safety tends to
mean in the reactor world, something leading to core
damage, etcetera. Is there a definition here for what
is important to safety in such a completely different
category?
MR. JAGANNATH: Here, the important to
safety is any structure or component needed to be able
to receive, handle, pack, and dispose of the waste.
That's for important to safety. And the other one is
the important to containment, waste isolation. There
are two requirements of --
MEMBER LEVENSON: Well, my question is
slightly different in that the section in the draft
report identifying things important to safety, some of
them seem to be things that if they failed might lead,
at most, to injury or death of one employee. That
seems to be a far different interpretation of
important to safety than in the reactor business.
MR. JAGANNATH: Here, important to safety
is defined in terms of the dose, not in terms of risk
as a question of that. The dose is based on
consideration of risk, but the rule requires us to
comply with the dose.
Basically, if an event sequence leads to
a release which is in excess of the dose, we make sure
the design and structure -- the dose is less than the
limit in the requirements.
MEMBER LEVENSON: The dose to which the
facility should be regulated, do you mean?
MR. JAGANNATH: Yes. The design has to
comply with the performance objectives.
MEMBER LEVENSON: Yes, okay. But my point
is that injury to an employee inside the plant is
significantly different than the dose to people 18
miles away.
MR. JAGANNATH: Yes. This comes under
Part 20 regulations. That has different dose limits,
different procedures.
MEMBER LEVENSON: Okay.
MR. JAGANNATH: Safety does not go in
terms of that. We have consideration of Part 20 as
one of the requirements. That also will be a
consequence.
MEMBER LEVENSON: Yes. My point was that
there is some things identified as important to safety
that I don't think by any stretch of the imagination
can lead to an off-site release, and yet they are
listed as important to safety.
MR. JAGANNATH: The work done by DOE is
based on community analysis, judgments. They went
through a whole list just to get started. It's not a
final list.
CHAIRMAN HORNBERGER: Banad, are you
saying that you -- there are occupational exposures
that are taken into account as well? This would be
the -- this would not be the 25 millirem?
MR. JAGANNATH: No, no. This is
15 millirem. Part 63 also requires compliance with
Part 20, which is worker dose requirements that they
also comply with. We just -- you know, in
discussions, we always focus on the public dose. But
Part 20 is also part of the requirements, compliance
with that and also compliance with ALARA requirements.
CHAIRMAN HORNBERGER: Does that make sense
to you, Milt, that they would have as their safety
case the occupational exposure?
MR. McCARTIN: Well, yes. Tim McCartin,
NRC. 63 does define important to safety, and it's
with respect to meeting the dose limits for Category 1
and Category 2 events, which are the off-site doses.
MEMBER LEVENSON: Well, then, I guess the
question is, when you get to the detail level, is
whether things now on the important to safety list are
correct based on that definition.
MR. JAGANNATH: Both compliance with doses
and Part 20 are considered in arriving at the safety
items.
This list of items important to safety are
also for their use down the line in dividing them into
in terms of categories and for quality assurance
purposes.
Continuing, the next chapter is a design
of these structure, system, and components, which are
identified as important to safety. These are --
supposedly, these are the ones that have to be
functional all the time. So we want to make sure they
are designed properly. We see deterministic are
prescriptive, present an evaluation for them.
And there is another subitem. As part of
the compliance with 10 CFR Part 20, there is a
requirement for compliance with ALARA requirements.
It is as low as reasonably available. This doesn't
have that much of force -- prescriptive requirements.
But, still the design has to comply with these things.
So we looked at the design from that perspective also.
That's another separate chapter within the preclosure
safety assessment.
The other two big sections outside of the
preclosure safety assessment -- one, plans for
retrieval and storage of radioactive waste. This is
required in the regulation. And the other one is
plans for permanent closure and decontamination or
decontamination and dismantlement of surface
facilities. This kind of mentions the several
sections in the Yucca Mountain review plan.
This one is like a block diagram.
Basically, it shows the logic within the review plan.
This follows the same logic as the definition of the
preclosure safety assessment. You'll note that
there's a dotted line at the bottom with two blocks
outside. One is the retrieval plan; another is the
permanent closure at the very end.
Above the dotted line are the several
blocks which contain so-called Yucca Mountain
preclosure certification study. Each of these blocks
has a corresponding section in the review plan, except
the first block has two sections. One is a site
description; the second is a design. And the last two
blocks, which are design basis criteria and the design
review, that is one chapter. So there are 10 chapters
with 10 blocks in there.
This follows the same logic of a site
description/design description. The next one is the
potential hazards. That leading to the next one is
the identification of emergency consequence, and
categorizes them as Category 1 or Category 2. Then,
the consequence evaluation.
Based on the results of those things, you
identify the structure, systems, components, important
to safety. There is another concurrent review of the
ALARA as a part of that.
This leads to establishment of design
criteria and the design of the structure, system, and
components required in safety. All of these are part
of the preclosure safety analysis.
One of the end products is the so-called
Q list, which contains the so-called safety items.
Another subgoal out of that would be further
development and validation of this based on the
important to safety and risk significance. This is
the whole logic of the preclosure portion of the
review plan.
I'll talk about how the risk-informed,
performance-based approach is taken. Basically, the
purpose of the review is to evaluate compliance with
the Part 63 dose requirements. One is the dose
requirements of the public and workers, ALARA
considerations.
These also are based on risk from
radiation exposure. That's mainly considered risk in
the dose consequence.
Part 53 has a definition of preclosure
safety, how we do that. It's, again, a systematic
examination of the site design, hazards, initiating
events, the event sequences. In that also we consider
the -- in going through these things, we consider the
uncertainty in data when you go through these things.
And then you find the event sequences.
The event sequences are defined on methodologies used
in PRA, you know, all those technical methodologies.
We use them in the event sequences.
Depending on the event sequences, you may
use the dose consequences. These dose consequences
and the unit sequences, in terms of the category they
are used, further in identifying structure, systems,
components, important to safety. And those -- they
are touch and go for the design of the same thing,
which are required in safety.
And the results of the design may be
linked to greater quality assurance. The results may
be used in that part.
This is the whole focus. The staff review
will focus on how DOE performs their preclosure safety
assessment. And then, our review will be -- it
depends on the relative significance within that
safety system or safety components.
MEMBER GARRICK: How much knowledge did
the team have of how DOE proposes to do their safety
analysis in the preparation of your approach to do
preclosure safety analysis?
MR. JAGANNATH: We had one detailed
technical exchange last year. There were several
interactions. DOE, as a result of the detailed
technical exchange where we expressed a lot of our
concerns on their proposed methodology. They will
produce the so-called PCSA guidance document,
preclosure safety assessment document.
It is for their internal staff use, but it
may be something similar to our review plan for their
staff. We just brought it to -- like a read back. We
are not -- that was their document. We plan to review
it thoroughly. They expect our feedback, that at the
end we would have a thorough knowledge of what
approach we are taking.
Based on the discussions going on, they
are considering the hazards. They want systematic
hazards, initiating events. They are considering
uncertainties in the data, failures in terms of the
combinations that they use, all the things you would
do in a systematic way they are approaching.
MEMBER GARRICK: So both approaches seem
to be --
MR. JAGANNATH: Parallel?
MEMBER GARRICK: Yes. And somewhat rooted
in the process hazards analysis, integrated safety
analysis way of looking at things, right?
MR. JAGANNATH: Well, it is. I don't want
to put a label on one of those things, but we are
considering all of the components of these things. So
structure, system, description, the hazards, the
frequencies, uncertainty in the event sequences. I
really think those -- then, using all of these things
together to identify important to safety.
We do not go in terms of risk at the very
end, because it is not required, and the regulations
kind of splits it in Category 2, so that -- it's a
restriction on how we use the resource.
MEMBER GARRICK: Okay. Thank you.
MR. JAGANNATH: In the review plan,
acceptance criteria are not very prescriptive. Since
it is a risk-informed, performance-based approach, we
are left in a fairly general level. We are
identifying what needs to be reviewed, and DOE has the
flexibility to come up with their own design criteria
as long as they can justify it and demonstrate that
they are used properly.
The staff review will be focused on the
safety-related items. We have developed what we call
a PCSA tool. It's like a software with a lot of
modules in it, where you store the information ahead
of time, the description data, event sequences, and
it's a module of software to do the event tree/fault
tree analysis. That part of it is another module
which can calculate the doses.
Then, the interpretation of the results we
use -- the tool does not interpret the results. We
interpret the results to come up with safety items.
And, again, for the analysis we can come up with the
quality degradation system.
Our review will be focused. It's like a
confirmatory tool. This preclosure review is more
than just using the PCSA tool. There are other areas
which are done outside of this tool. So this is --
that is where the -- in the context of the review,
that's where the tools are really focused on.
All of these things we have plans for
retrieval and alternate storage. Again, there are no
prescriptive criteria. DOE has the flexibility. We
only require the plan from them. The plan has to
demonstrate that the retrieval operation will comply
with the performance of the reviews, and it's
something feasible.
The next one is plans for permanent
closure, decontamination, and dismantlement. Again,
the acceptance criteria are fairly at an acceptable
level. We expect this part of the plan to be really
general. Towards the end, they will finalize it. The
design has to consider the dismantlement,
decontamination, initially as one of the activities
coming up. That's why we bring it up. And there are
some NUREGs available. Hopefully, they will follow
all of those things.
This concludes my brief presentation of
what's in the preclosure plan. Mostly this is risk-
informed performance, because we do not have any
prescriptive requirements. They consider all of the
aspects of risk in terms of hazards, initiating
events, frequencies coming out of that. It's totally
performance-based, because the demonstrating comes
from the dose.
CHAIRMAN HORNBERGER: Thank you, Banad.
MR. JAGANNATH: Do you have any questions?
CHAIRMAN HORNBERGER: Questions? Milt?
MEMBER LEVENSON: Yes. I have one, which
is really not directly related to your presentation
but curiosity. I know there are restrictions on what
you can put in Yucca Mountain to some extent. The
last bullet -- you're going to have a mountain full of
very, very high-level, etcetera. Would it be possible
at the end to dismantle that equipment, move it into
the shafts before you seal it, rather than undertaking
shipping stuff to new sites and new sets of
regulations, and new everything.
MR. JAGANNATH: You don't know what will
happen until years from now.
MEMBER LEVENSON: No. I'm wondering if
legally there was a restriction against that.
MR. JAGANNATH: No. At this point, there
is no restriction. The regulations are fairly
straightforward. Our guidance is for whatever they
use for the -- in the powerplant decommissioning
guidance at this point.
The only requirement is that the design --
they should have it in mind that we -- the designer
keeping that in mind.
MEMBER LEVENSON: Yes. The point is that
if you design it to be dismantled and shipped a long
distance, the design might be quite different than if
you had the ability to just move massive pieces of it
into the drift and leave them there. So it does
impact the design.
MR. JAGANNATH: I expect DOE plans to put
it in the repository, but we'll know that when they
submit the application.
CHAIRMAN HORNBERGER: You'd prefer not to
see it shipped --
(Laughter.)
-- right? Tim?
MR. McCARTIN: Tim McCartin, NRC staff.
I'd just like to correct what I said when I talked
about the important to safety. For Category 2 events,
it is off-site doses. Category 1 does include both
worker and off-site doses, so we would look -- during
normal operations, worker safety doses would be a
factor in determining important to safety.
MEMBER LEVENSON: Is that the same
criteria used on reactor plants?
MR. JAGANNATH: Part 3 of the reactor.
MR. McCARTIN: Apparently, no.
CHAIRMAN HORNBERGER: The question was the
phrase "important to safety," I think, not protecting
workers.
MR. JAGANNATH: Protecting workers is --
CHAIRMAN HORNBERGER: No. Protecting
worker health and safety is a whole separate category.
It may or may not be more restrictive. But importance
to safety has a very specific connotation, and it just
seems to me we're using a completely different
definition here than the reactor field, and I'm
wondering why.
MEMBER LEVENSON: Well, it is defined in
63, and that was the definition we proposed. So we --
I don't believe we got any comments on that particular
definition.
CHAIRMAN HORNBERGER: Other questions for
Banad?
MEMBER GARRICK: Well, I have some
questions about the details of the procedure, but I
think they are better dealt with offline, because they
are -- they would be technical. So I think I'll
defer.
MR. JAGANNATH: I'll be glad to meet with
you.
CHAIRMAN HORNBERGER: Do you mean they
have to do with probabilistic risk assessment?
MEMBER GARRICK: No, because they don't do
that. It's a little -- it does have to do with how
they structure their scenarios and some of the
different modeling. And I would prefer to talk to
some individuals about that than take the time of the
presentations.
CHAIRMAN HORNBERGER: Can you give me an
example of a Category 1 event and how that would be
handled? Just to lend some concreteness here.
MR. JAGANNATH: Category 1 is in the fuel
handling building. Many times there are accompanying
waste packages assemblies, dropping them in the dryer
and the dry handling part of it. Category 1 is
frequency less than 10-2.
CHAIRMAN HORNBERGER: Okay.
MR. JAGANNATH: In the same -- Category 2
is -- has some events in the pool where the bare
assemblies bump against each of the underwater -- they
are -- some of them are Category 2.
CHAIRMAN HORNBERGER: Okay. So these
kinds of events would be similar to events that would
be encountered in other fuel handling facilities.
MR. JAGANNATH: Yes. But maybe it's more
moving, but in the same -- same kind of thing.
CHAIRMAN HORNBERGER: So I guess my point
is that we -- there is not a lot that is "first of a
kind" here. We have a lot of information and
experience in dealing with these things.
MR. JAGANNATH: Correct. That was the
basis for which our long-time -- it was put on the
back burner in terms of resources and effort, because
the agency has experience. This is something done at
the powerplants and other facilities, moving fuel and
handling fuel and other things.
There is some work done on this also. We
intend to use all of those things. There is enough
knowledge available. We have to use it appropriately
as it applies to this case.
CHAIRMAN HORNBERGER: Questions from
staff?
Okay. Thank you, Banad.
MR. JAGANNATH: Thank you.
MR. McCARTIN: Before I start, actually,
if you have the complete set of the -- I actually have
a separate set for my presentation. The one in -- the
complete set is an earlier version.
CHAIRMAN HORNBERGER: You have a separate
one.
MR. McCARTIN: Yes. Mine is Rev. 2.
CHAIRMAN HORNBERGER: Do you get away with
changing your slides when you do presentations to the
Commission?
MR. McCARTIN: No.
(Laughter.)
At least not at the last minute.
Okay. I'm going to try to walk through
the postclosure safety assessment portion of the
review plan today. And the presentation is decidedly
short for all of the topics and the model abstraction,
etcetera. I will -- that leaves more time for the
committee to ask questions, and feel free to -- I'm
sure you have no inhibitions about asking questions.
There are two main areas for the
presentation. One, I'll talk about the organization
of the safety assessment review, and then talk a
little bit of how the risk information performance-
based aspect of our review comes in.
First, in terms of the organization,
obviously, the review plan is based on the compliance
with the performance objectives. Then, the order is
very important, and it was done for a very particular
way. You'll see that second bullet is actually the
first thing looked at -- system description and
demonstration of multiple barriers.
Clearly, in terms of the analysis DOE has
to do, this is probably the last section you write.
We want to read it first, and that was done for a very
particular reason. It basically is telling the big
picture, the story of why the repository is working.
Before we go into the other sections of the review,
we'd like to get basically an overview of why the
repository is working, and that's why that section is
first.
We would expect the Department of Energy
will be writing that section last, but we'll go
through the multiple barriers. That information, that
overview, is used to focus all the rest of the
reviews.
Next, would be the scenario analysis,
event probabilities. What have you considered? What
have you included in the analyses? What have you not
included in the analyses? Part of that right now is
the identification of the events with probabilities
greater than 10-8 per year. As you know, we have a
proposed amendment to 63 out there for unlikely
events. That will come in. This section of the
review plan would be revised depending on what that
final rule amendment comes out as.
Next, we go into model abstraction. These
model abstractions were derived from the key technical
issues. There are integrated subissues, we think, a
little more related to -- a little better related to
how we would do the review in terms of the different
processes, aspects of the repository.
We think it gives us, as stated there, a
comprehensive review of system behavior. We have
everything on that list we think are the things we
possibly need to look at in detail. Will we look at
all those 14 subissues in the same detail? No. We
want the list to be comprehensive. We will tailor our
review, obviously, based on the multiple barrier
aspect, what seems to be the most important to DOE
making their safety case.
And we have cross-walked at times the KTIs
and the subissues. We believe they are all captured
there. You won't see that in the review plan. But
the next slide I -- for completeness, I have the list
of the 14 subissues. I don't know if there's any
reason for going through all of them. I believe the
committee has seen those before.
But we think the important point -- in
this list, we believe we've captured all of the topic
areas. And as I said, the importance for the review
plan is we want to be ready to review every one of
those topic areas. The detail and depth we go into
the review will depend on the risk importance of each
of the subissues.
CHAIRMAN HORNBERGER: And these are your
integrated subissues, is that right?
MR. McCARTIN: Yes.
CHAIRMAN HORNBERGER: The list?
MR. McCARTIN: Yes.
CHAIRMAN HORNBERGER: Okay.
MR. McCARTIN: And ultimately, at the end
of the review plan for this section, you have
demonstration with the standards. And there is three.
One is the individual protection standard, the
standards for human intrusion and the groundwater
protection standards. That's pretty much the
organization of the review plan.
Getting into more of the -- how is this
structured in terms of the risk information?
Obviously, at the top, we have the demonstration with
the compliance, the numbers if you will. Related to
that, there are three sub-tiers, and it all goes down
to more detailed information. We have the multiple
barriers, the model abstraction scenarios.
You can see that ultimately you get down
to each one of the model abstractions sort of fits
into a box, be it model abstraction, some more than
one box. Obviously, they all fit into multiple
barriers in some way. But all of this information --
the detailed model abstraction reviews all fall into
this.
And I guess if there is one thing I'm
hoping to make clear in this presentation, something
that if there is one thing that I felt has been
misinterpreted the most with respect to Part 63, is
that demonstrating compliance with the performance
objectives allows you not to understand fully the
site.
And the entire approach that we laid out
for postclosure I think give us the understanding of
the site. That is first and foremost. Ultimately, we
will look at the compliance with the numbers, but I
know at different groups we've heard implied that the
performance assessment is demonstration of compliance.
The NEA peer review somewhat talked to, well, you're
really -- if you're demonstrating compliance, you
really don't need to understand the site.
I personally don't understand how you can
make that assessment in looking at the rule and what
is required. And I hope to go through some of the
information that we're looking for. Ultimately, it's
the understanding of the site.
The last thing you do is the calculation
of the number. But the reason you believe and put
trust in that demonstration is all of the information
and understanding and --
CHAIRMAN HORNBERGER: Tim, let me ask you
a quick question --
MR. McCARTIN: Sure.
CHAIRMAN HORNBERGER: -- on that point.
Do you think that if you make conservative assumptions
at every turn in the road that you'd get to understand
the site?
MR. McCARTIN: That's a difficult
question. However, I think you -- in your
understanding, you need to allow for the fact that
there could be some information that is difficult to
attain, and you are left to take what you -- you might
believe is a conservative approach.
You do have to have some information to
defend that as conservative. If you're given that
information, I still maintain that you do have a
sense, an understanding of the site. And, in general,
I look at the Commission's decision as one that is
public health and safety protective. And that's their
decision to make.
In terms of if there are some conservative
approaches, and truly we would not disagree that they
are conservative, and you're still demonstrating that
you can meet 15 millirem, I believe that's okay.
However, having said that, I will say that
the part that -- I share the committee's opinion with
the TSPA-SR. The word "conservatism" was used far too
often, and what -- I interpreted "conservatism" in
many documents is that we believe if we collected more
information this parameter, this model, would become
less conservative.
But you don't have that information.
There is no guarantee that if you collect that
information you may find out that that parameter
actually that you thought was conservative is the
correct value. And there is a lot of what I would
consider putting in gut feelings into whether this is
conservative. I would say I don't believe that's very
useful.
MEMBER GARRICK: Isn't the issue, though,
Tim, that often what the public is asking for is no
uncertainty about the site. And, of course, that's
completely unachievable. What's really important is
how you represent the site.
You don't need to know everything about
the site to accurately represent what you do know
about the site. And the way you do that is, of
course, acknowledge and admit to the uncertainties.
If you do that systematically and deliberately, you
can represent what is known by the site in a rather
convincing way.
But in order to do that you have to admit
to these uncertainties. And I think that's where the
confusion comes. I think this whole issue of
precision is one of the most difficult to deal with,
because in most engineering facilities it has not had
to be dealt with in the same way that we're talking
about here.
Even though the uncertainties existed,
they were not -- there was not as much of an attempt
to manifest them. And now we're pushing that here we
have to manifest them, and so we need to make darn
sure that there is an understanding of the difference
between representing what is known about the site and
conveying that the characterization of the site has
been done such that there's no uncertainties about its
features, and that's not the direction that we can go.
MR. McCARTIN: Yes. I agree completely.
I think I've heard you say before, and maybe even
yesterday, to the Commission, we'd like to see the
analysts take their best shot.
MEMBER GARRICK: Yes.
MR. McCARTIN: And I think that's what
we're asking for in Part 63. We're pretty -- deal
with the uncertainties. Give us your best shot. And
I don't know if I like talking to conservatism,
because I'm not sure I know what that means. But if
you can talk to the evidence --
MEMBER GARRICK: Right.
MR. McCARTIN: -- and here is the evidence
we have, and then let someone decide whether you've
treated that evidence in an appropriate way or a
conservative way. But that -- the word "conservatism"
I think is troublesome. I prefer what the committee
has said -- make it evidence-based, give us the
evidence, and what you've done.
MEMBER LEVENSON: I think, as you know,
Tim, I don't like the word "conservatism" at all. One
of the things I've always recognized is that the non-
uniform use of it, even if everything you do is
"conservative," if they are non-uniform you can
introduce risks.
I've recently been involved in a dose
reconstruction project where there were 100 and some
isotopes. And, obviously, detail work couldn't be
done on all, so there was a screening analysis to
reduce it to a dozen that would be looking at in
detail.
Because of non-uniform conservatism, in
fact, a number of the more important isotopes were
rejected as being not important. And so the non-
uniform use of conservatism can introduce risks, and
I think it's that that we're really concerned with.
MR. McCARTIN: Sure. And I would agree.
And it may be one of those things -- I know we're
internally thinking harder of describing our approach
and what we're -- how we're dealing with uncertainty,
which I think is the key. And I think we may have all
in the PA area for Yucca Mountain taken a -- the easy
way out and used the word "conservatism" far more
liberally and in varied ways, and it has done a
disservice.
And I believe when we've developed our
code and parameters, I think the DOE -- I would like
to think they're doing that. I have a lot of
indication they are. But what you're looking to do is
have a uniform level of support for what you're doing.
Because these problems are drastically --
the areas that were involved, if you'll look at all of
these different integrated subissues, they have
drastically different uncertainties. And you've got
different ways to treat it, but what we're looking for
is a uniform level of support for the approach.
And then I have what I would maintain is
some confidence in the final result. But, once again,
I'm hoping that as I go further that it's the
understanding that's at this level that feeds into
this and gives you this number, and gives you some
confidence. And it's all -- our regulation, I think,
is directed towards getting that understanding.
One picture is worth a thousand words.
MEMBER GARRICK: That picture has a
thousand words.
(Laughter.)
MR. McCARTIN: Yes. Well, that's true.
Once again, in looking at our review, and
this first bullet with compliance with the performance
objectives, it's really what I've been saying. I
think the emphasis is on understanding the system.
That's the way Part 63 was written. If you read the
technical criteria, what we're asking in terms of
support for assumptions and models, etcetera.
I know the committee has talked about --
and also the TRB asked -- the TRB has talked about the
community access to talk about multiple lines of
evidence. I believe in the regulation we talk to
things like laboratory field experiments, natural
analogues. I'll show later where that sort of fits
in, we think, in terms of providing additional
support.
Once again, here is where -- and I talked
to the TRB last month and brought up that the -- we,
at the NRC, have never defined performance assessment
in a narrow way. And so when we think of multiple
lines of evidence, that's part of the TA. All of the
information that supports the credibility and the
belief in the modeling is part of PA.
I know that when the TRB talks about it,
they speak of multiple lines of evidence separate from
the PA. I think we're both after the same thing. I
don't think there's a problem, but I believe we -- I
think some of that may have developed to this -- the
PA and demonstrating compliance doesn't get you the
whole way. You need other information to make your
safety case, if you will.
We sort of cloak all of this under the
same you're demonstrating compliance. All of that
information support is included.
As I talked about, the risk information is
used to focus the review. Multiple barrier analysis
-- and you saw little -- we had some discussion
yesterday about barrier analysis. The rule requires
two things -- well, three things. Identify the
barriers, describe the capability of the barriers, and
provide the technical basis for that capability.
We believe providing that technical basis
is really the same -- will be the same as the
technical basis that's provided in the model
abstraction aspect. So it's not really a separate
kind of thing, and we mention that in the rule.
But it's important that we are looking at
barrier capability. And I think the Commission -- we
thought about what to do for barriers for the -- from
the proposed rule all the way to the final, and it was
debated internally. We had many discussions. We've
thought about it a lot. I believe the Commission
ended up where they should be -- at barrier
capability.
Barrier capability is implying I have an
understanding of what these barriers are doing. The
reason I like that is that if you go to other things,
such as just looking at the dose number in some cases,
you can be misled.
And for the simple reason -- let's say
there's some radionuclides because of retardation
never get out of the actual system. It's always zero.
If you're just looking at the dose, you're totally
opaque to the fact that the natural system is holding
up those nuclides essentially forever, on the order of
hundreds of thousands of years.
Just looking at the dose, you see iodine
technetium. Well, the reason you see iodine
technetium is they are very mobile. They're mobile
just about everywhere in the world. There's a reason
we see that. We didn't not bury this waste to retard
iodine technetium. And so just looking at the dose
can sometimes be misleading.
If you start describing the capability --
and I have some slides later that will get into that,
tell me what this barrier is doing and you can see
that the barrier -- I know in terms of the simplified
analyses you might just look at iodine technetium and
neptunium. But in barrier capability, I think it
would be very important.
There's a reason you don't have to include
all of those other radionuclides. It's a natural
system. And I think that description of that
capability for the natural system to retard and hold
up those nuclides is very important to the decision
the Commission has to make. And I think in looking at
the barriers you need that kind of information.
Obviously, the multiple barrier analysis
will help -- as I said, that information helps focus
the remaining -- all of the other reviews, be it model
abstraction scenarios, etcetera. That's very
important.
In terms of the scenario analysis, we have
both the nominal and disruptive events. There really
aren't that many disruptive events. But, certainly,
in the nominal scenario, there is a plethora of
processes to be considered. And there is a lot of
evaluation there to look at what's included in the
analyses and what is not.
And, ultimately, we think we'll be looking
at unlikely and very unlikely events. And, as you
know, the unlikely events would be screened from the
human intrusion and groundwater protection analyses.
Model abstraction. Right now, we've done
a lot of performance assessments -- the DOE has, NEI
has. We've made use of all of that. I think there is
prior information, prior knowledge that's used to help
in developing this part of the review plan. There is
no question that the model abstractions will have
varying risk significance. Part of that depends on
what the DOE's safety case is.
When the application comes in, we think we
have all of the right pieces here. We'll be able to
tailor that analysis once the application is in. In
terms of the abstraction, there is five aspects to
each model abstraction that we look at, and here is
where the understanding of the site comes in.
First, an adequate system description of
model integration. Well, what does that mean? Well,
we're looking for DOE to describe how they've -- for
this subissue, how they've integrated into the whole
analysis. We want to understand what they've done,
how it relates to other aspects of the model, what
feeds in, what feeds out, but getting an idea of what
is being done in that system, that issue.
Next, we would look at, is there data in
model justification for what they've done? Then, of
course, getting to uncertainty, adequate
characterization for the parameter uncertainty, and,
as Dick Codell and Sitakanta pointed out yesterday,
there are certain things we want to look at in terms
of the risk dilution, etcetera. How are you
specifying this range, etcetera? And there is things
to be careful with in terms of arbitrarily expanding
a particular range.
Model uncertainty -- as you know, the rule
requires DOE to look at alternative models that are
consistent with the information.
And, finally, adequate support for the
model abstraction output. I think here, but
potentially also in this area, but here primarily,
this could be where you have the multiple lines of
evidence.
For example, you might have for the waste
package a corrosion rate of X. Waste packages are
lasting for X thousands of years. There could be --
as DOE has indicated, there are some particular
minerals in nature that you can look at to get a sense
of, does this make any sense at all? And so I think
you have multiple lines of evidence.
I think you can do that at all the
subissues, be it transport in the unsaturated zone,
infiltration. There are many things that I -- but I
think here is where they tell us, "Here is the result.
Here is what our model is doing. And here is some
analogue information. Here is some potentially
experimental information, field experiments,
laboratory experiments, that support the ultimate
value that's coming out of your model."
Demonstration of compliance. Having done
the model abstractions, and I think that's where --
given you have that understanding, you think the
models are appropriately integrated, there's
justification, you have a sense of how uncertainty was
dealt with, what your support is. I think you can
easily go, then, to the demonstration of compliance.
What is the final dose number?
And, as you know, their requirement is
reasonable expectation. We want to make sure,
certainly, that probability estimates for the
scenarios and the consequences -- there is certainly
a mathematical correctness there that we want to make
sure that -- you know, that the numbers have been
added up correctly.
Certainly, looking at parameter
uncertainty and the model uncertainty, how that's
manifested in the final dose number, we've looked at
it at the subissue level. When you look at given --
you understand how uncertainty is manifested in the
subissues, do you see a dose result consistent with
your understanding of that uncertainty?
And as Dr. Garrick pointed out, we are
using -- essentially, we would use all three. The
performance assessment tool would be the basis for all
three performance objectives. Clearly, the
groundwater protection is an intermediate result to
the dose. You have to get a concentration.
Obviously, for some nuclides it's
15 picocuries per liter. Other it's four millirem to
the organ or the whole body. And so you have to do
some manipulation with that information, but
ultimately you're taking the concentration and you can
feed it off into the all pathway dose assessment or
into a post processor to demonstrate whether you've
met the groundwater protection requirement.
CHAIRMAN HORNBERGER: Tim, a quick
technical question.
MR. McCARTIN: Yes.
CHAIRMAN HORNBERGER: For the groundwater
protection, is that the concentration with everything
dissolved in 3,000-acre feet?
MR. McCARTIN: Yes.
CHAIRMAN HORNBERGER: Okay.
MR. McCARTIN: And, finally, I just want
to get back to, well, what kinds of analyses might the
staff do to support these reviews? First and
foremost, I think we want our own quantitative
understanding of each barrier's capability. And by
that, as I mentioned before, we're looking at the
capability of a barrier.
Certainly, the waste package is an easy
capability to describe. While it's operating, there
are no cracks, no holes. There is no release, so it's
zero. When there's a -- however, we also have a
limited amount of water contacting the waste. We
think that's important.
Slow release rates from the waste form.
These things don't release that quickly. Iodine
technetium -- one of the reasons you see that is they
have a gap fraction that is available for an
instantaneous release. It's a fairly high percentage.
I'll say two to four percent. That's a lot of release
and over a very short time period. One of the reasons
-- once again, iodine technetium show up, mobile, has
a gap fraction, high solubility.
Delay of specific radionuclides due to
retardation, and I guess this is very important.
Iodine technetium -- a very, very small percentage of
the inventory is lightly retarded. But the fact that
nothing else -- you're seeing virtually none of the
other radionuclides, they're retarded here.
I think we need to do some of the
calculations to get a sense of what's being retarded,
because the fact that we should not be -- well, we
want to be focused on two things. Things that give
high doses, but attributes of the system that result
in zero doses, are also important. Just like people
are concerned with the waste package, it's no releases
for a long period of time.
The saturated and unsaturated zones have
the capability to provide no releases for times
sometimes much longer than the waste package for a
large host of radionuclides. We want to make sure
those zeroes are appropriately zeroes.
Certainly, we'll do sensitivity analyses.
Dick and Sitakanta I thought did a good job of giving
different areas we're looking at. I think the
strength of the PA program is you never want to be
satisfied with where you're at. I think you want to
constantly look to new techniques to see if you have
a better way of analyzing the problem, and I think we
continue to look at different approaches.
Dick mentioned the neural networks. There
is things that maybe there is other areas that provide
analysis ways/methods to look at the problem that may
be helpful, and I think we want to explore that.
We certainly want to be -- and we are
working diligently at understanding differences
between our sensitivity analysis and the DOE's.
Ultimately, we are interested only in DOE's, and
that's our focus.
And, as you know -- and we've commented
about this before -- for example, the diffusional
release that DOE has, it dominates the early release
for their waste package, or some of the things --
there are differences in the unsaturated and the
saturated zones for matrix diffusion between our
different models.
The beauty of that is we all came to our
models with a certain understanding, working through
the DOE's model, and our model I think is strengthened
by understanding strengths and limitations of both
approaches. But, certainly, we'll do the sensitivity
analyses, but you want to be mindful of -- because
there are some important differences.
CHAIRMAN HORNBERGER: Tim, in fact, as we
know, the sensitivity analyses are model-specific. So
you lay your testing as the sensitivity of TPA when
you do sensitivity analyses on TPA. And, certainly,
it may give you some insights as to what you want to
look at at the DOE case. But are you -- do you have
plans to actually do sensitivity analyses on the TSPA
itself? Or just try to interpret DOE's presentations?
MR. McCARTIN: No, we're not going to try
to -- well, we certainly try to interpret their
presentations and ask questions, etcetera. But we do
have the Goldsim model in-house, and we're --
currently, Dave Esh is working on an effort to bore
into that, down to the last parameter, and understand
how their model is working, what the assumptions are,
what the parameters are, and where -- I think in the
next year we're going to move to be doing far more
work with DOE's model than with ours.
We have a limited capability for running
their model. They have a different approach than we
do. If needed, I think the Department would probably
be willing to do some particular simulations for us.
But right now, we won't run their model, but we do
have their results. And I think -- I think it will be
a very interesting exercise, and I think it will help
us get even more ready for reviewing their model when
ultimately --
CHAIRMAN HORNBERGER: I guess I'm just
trying to figure out at the end of the day if, in
fact, the license application comes in and you have
sensitivity analyses, how does this play into your
review of --
MR. McCARTIN: Well, it's risk
information. It's in a broad area of, where do we
want to focus the review? We clearly -- there are --
CHAIRMAN HORNBERGER: But your intention
isn't to give DOE guidance on how the sensitivity
should be done.
MR. McCARTIN: Oh, no. Absolutely not.
No, no, no.
MEMBER GARRICK: I think part of what
George is getting to is the chicken and egg problem
you have of, on the one hand, early in the analysis
identifying what's important, and on the other hand,
later in the analysis, allocating the resources in
accordance with that.
And sometimes you don't always discover
what's important until late in the analysis. And so
that has to be done with great care.
MR. McCARTIN: Yes, I would agree
completely.
MEMBER GARRICK: Yes. And the other thing
relating to the review plan is that the review plan is
very specific with respect to the abstractions that
you're going to consider. And I know that the whole
abstraction process has been a major issue and concern
of the staff.
I hope that the review plan has the
flexibility to adjust to additional abstractions that
are listed here or a restructuring of the abstractions
that are listed here, because --
MR. McCARTIN: Yes. I think we have a lot
of flexibility. Now, the bins are broad enough that
there is a lot of information in a particular area, be
it the, you know, corrosion of the waste package. I
mean, you know, you'll have a bin for corrosion of the
waste package. Within that, DOE has to talk to what
kind of water chemistries, etcetera, that are
impacting it.
And I think that's where the flexibility
is in that we haven't pointed to any particular water
chemistry they have to consider. But you're right
that, have you missed something? You really want to
look carefully at the FEPS analysis. What have you
included? What have you not included? And why?
And there is a lot of work there to make
sure you -- gee, now you don't think this is possible,
but it could have a very big effect. And it's not a
simple problem, but I think the model abstractions are
broad enough that I don't know if we would need any
further model abstractions.
But there is nothing to preclude us from
taking some out, adding some in, but I think within
the model abstraction there is a lot of -- I mean, on
the plus side, I think from the NRC's standpoint, we
gave DOE the flexibility. You need to describe what
you've done and defend it. That gives complete
responsibility to the Department.
We're not going to tell you what has to be
in there, but we're going to review it and --
MEMBER GARRICK: Yes. And the issue is
the completeness.
MR. McCARTIN: Yes.
MEMBER GARRICK: Have we appropriately
mapped from the process models and the analysis models
that are very detailed to the TPA.
MR. McCARTIN: Yes, absolutely.
MEMBER GARRICK: And the completeness of
that process is a very important part of what you're
trying to do.
MR. McCARTIN: Yes. Yes. And that's one
area where I think -- and the proof will be when and
if it actually happens, so there's no guarantee that
a license application is filed. But if it's filed,
that's why I like the barrier description up front.
MEMBER GARRICK: Yes.
MR. McCARTIN: They provide, here is why
it works. And I think at a broad level, that's where
you're looking at, does this make sense? Can I think
of things that could be there that would defeat that
barrier? Here's it's capability, etcetera. And then,
with that information, you go into the model
abstractions with a sense of where in the Department's
safety case it appears that the capability is the
largest.
I'd like to think that, having been
looking at high-level waste disposal and performance
assessment for around 20 years, that at least for the
model abstractions the big ticket items we have. But,
you know, there is always new information potentially
coming in.
MEMBER GARRICK: The only point of the
comment is that we don't want to let the review plan
bound our thinking about what we consider.
MR. McCARTIN: Absolutely. And that is a
very good point, a good word of caution to the staff.
And I think it's incumbent on us to look at what's
said in the review plan and make sure that that
thought is in there somewhere.
And maybe it needs to be explicitly stated
somewhere up front, but you're right, and it's -- the
review plan is to give an order so that -- of the
review so that we make sure we cover all of the things
we do. We need to cover and adjust the review
accordingly, but you're absolutely right. Along those
lines, we would expect to do focuses analyses.
I think one of the things we've strived in
our TPA code -- and, as you heard yesterday, 5.0 will
be -- we're in the thinking process for that -- we
tend to try to make a code that's flexible to
analyzing a variety of different concepts. We have
many different alternative models for ways that the
waste package -- we have two waste package failure
models, two different -- or three or four different
models for release, except we have different ways to
look at the problem.
I think we'll be able to -- if we have a
question about an aspect of the behavior, we'll be
able to do some focused analyses with the PA looking
at a very specific issue. Also, we would expect
process level models, that for some things you're just
going to have to do a much more detailed model and
see, do we agree that that process can be eliminated?
Seepage, non-isothermal flow, etcetera,
are things where you may have to do more process-level
models. And I think we have that capability and that
support where we go back to the Department to ask --
we need more information about this. Ultimately, in
our review, that's what we're looking -- what do we
need more information on? We need to support our
basis for that.
Groundwater protection standards -- we'll
certainly -- as I mentioned before, it's really an
intermediate result to the PA. We don't think that
this adds any additional burden to the calculation.
We will do it. Or the Department will have to
demonstrate that. Unlikely events will not be
considered, and, as I mentioned, the rulemaking to
make that a more quantitative value rather than the
qualitative nature of it is underway.
For human intrusion, a key part of the
standard that we adopted is that DOE needs to
determine when this will occur. We certainly have to
review the DOE analysis of when the occurrence will --
of the intrusion would occur.
And, finally, I thought this would go
quicker, but I got some good questions. I don't know
how much time I was given. I probably went over, but
I've been accused of that before.
Pat felt -- he's after me. He says he may
not get on when I got up, so --
In summary, fundamentally, Part 63, the
requirements, the review, is looking at the
understanding of the system behavior. That is key and
foremost. We would expect to be looking at the
technical basis for that understanding -- would be
commensurate with the risk importance. And we
certainly will do a variety of focused analyses to
assist our review.
I'd be happy to answer any questions.
CHAIRMAN HORNBERGER: Thanks, Tim. Let's
see, I have a couple of questions. Let me kick off
with -- to a certain extent I guess we've covered
this, and perhaps we may reach an agreement that we'll
never use the conservatism word again.
But are you confident that you will have
given or will be able to give DOE appropriate guidance
on what you mean by evidence-based? Do you think that
that's clear in your acceptance criteria that what
you're after is enough evidence to support the case
that they make?
MR. McCARTIN: That's a good question. I
mean, the quick answer is, yes, I'd like to think that
the acceptance criteria are clear enough. Having said
that, though, I think the uncertainties are so
different between the different subissues that there
is really no simple answer.
That I think ultimately right now it's
coming about by virtue of the agreements that we
reached that I think gave the Department an idea of
what -- where we thought support was needed further,
where support was appropriate. I think we're going to
have -- continue that dialogue, that prelicensing
dialogue, on the agreements that I think is critical.
It's one of those things, the review plan
can only go so far. And I think we've given it a
framework, but I guess I'm not confident that the
review plan could go all the way that would be needed.
I think it's really sitdown conversations with the
Department.
MR. CIOCCO: Jeff Ciocco with the NRC
staff. We did add some language up front in the --
it's on page 4.2-2 and 4.2-3 on conservatism. It
doesn't necessarily reflect back in the acceptance
criteria yet. As Tim said, this was kind of a high-
level -- we want to give staff some guidance, and this
was really in response to your letter on the TSPA-SR.
We went back and felt that we needed to
address the issue. And you can read -- there's a
couple of paragraphs in there, and it was kind of the
basis, kind of a general framework for dealing with
conservatism. But it's not -- as Tim said, it's hard
to capture back in the specific acceptance criteria.
And we're probably not there yet in that area, but I
think we have major feedback in that area as far as
what we have.
MR. McCARTIN: Yes. I mean, that's --
yes, that discussion is more along the lines of you
need to be careful when you go down the conservative
path, as compared to how much evidence do you need to
support --
MR. CIOCCO: Right.
MR. McCARTIN: -- something. And it's
more along some of the concerns the committee has had
in terms of, well, you justify this approach. It's
conservative. I don't have to do any more.
But is it truly conservative? It's
conservative for maybe you're getting more water into
the drifts. But depending on what modeling approach
you want to look at, gee, more water could make the
salt concentration on the waste package more dilute.
And so it extends the lifetime of the waste package.
So the fact that it's -- you're saying
it's conservative for water, yes, but as I know the
committee has pointed out, it may not be conservative
in terms of what the final dose estimate is. And
there is --
CHAIRMAN HORNBERGER: That's a good
example for my second question, which was, are you
confident that even though you have these what are
called integrated subissues that you really are going
to integrate and not be stuck in stovepipes for your
analysis.
Your example of water changing salt
concentration might be --
MR. McCARTIN: Sure. Yes. I believe so,
but it is a challenge. There is absolutely no
question about that. The reason I have confidence is
over the past month or so we've had a number of what
some people called brutal meetings. Brett Leslie and
Chris Grossman were doing the risk ranking of the
agreements, etcetera. I know they've defined it as
brutal.
Now, they had to coordinate all of them,
and maybe that's why. I found -- I attended all but
one of the 14 meetings, whatever they were. They were
fascinating, and they were tremendous discussions
between -- with the staff, both here and at the
center. And getting to just that issue, there were,
I'll say -- people were encouraged and everyone took
up the gauntlet appropriately.
If you have any stake in this issue, you
need to be at this meeting. And there was a lot of
discussion between -- while we divvy the work up
between different KTIs, or different subissues,
however you want to -- there will always be some of
that.
The cross-discussion is absolutely
critical, and that -- those discussions, which will
continue, I think are fostering a very high degree of
integration. And I think the agreements -- although I
know the agreements have taken some criticism, if
there is one very, very positive thing with the
agreements, I think it's people have really focused
on, how does this relate to my -- and, actually, it's
been a tremendous integrating tool.
And I think those meetings are going to
continue, but I -- I think in that sense, yes, we will
be able to integrate.
Pat, do you have --
MR. MACKIN: This is Pat Mackin from the
center. Just one clarifying point. Each of these
subissues is explored by a team, which is, by design,
multidisciplinary. So that anyone, as Tim would say,
that has a stake in any issue, whatever their
discipline is, is involved in that team.
CHAIRMAN HORNBERGER: Thank you. Milt?
Raymond?
VICE CHAIRMAN WYMER: I have one fairly
detailed question, Tim. Under model abstraction, you
say each model abstraction uses the same five generic
acceptance criteria. One of those is adequate
characterization and propagation of data uncertainty,
and I guess I would add to that the lack of data
uncertainty.
(Laughter.)
Are you reasonably comfortable that you
can, in fact, propagate the uncertainty -- the
uncertainty reflected in the dose? And it seems to me
that's extraordinarily difficult to do, and the same
thing can be said about the abstraction or the
propagation of model uncertainty. Those seem to me to
be very difficult things to do, considering what you
haven't had to work with.
MR. McCARTIN: Right. Well, certainly, in
terms of -- we have techniques for the parameter
uncertainty, and you can vary parameters and see what
it -- how it changes dose. In terms of looking at
model uncertainty, you can try different conceptual
models and see what the ultimate effect on dose is.
But at the heart of your concern is -- at
least in my opinion, is that, have you captured all of
the uncertainty? Have you -- there is certainly
knowledge -- you're only putting in what you know.
There are certain aspects of it that, gee, what I'm
not certain about I may not even have in the model,
etcetera.
VICE CHAIRMAN WYMER: How do you propagate
it?
MR. McCARTIN: Well, I don't think you
can, but I think you have to look at -- I will fall
back on you have other aspects to look at to help you
make your decision, and I look at the barriers
ultimately. That's part of why multiple barriers are
there is a recognition that this is a hard problem to
quantify the uncertainty for. And we'll have this
multiple barrier system, because we -- we have that
uncertainty.
And I look at when you look at the
capabilities of those barriers, you'll have a sense of
what they're providing. And, once again, each of
those will have some uncertainty, but it's at a lower
level than the dose. I think you use that kind of
information to help you make the decision.
VICE CHAIRMAN WYMER: I suppose I was
reading that a lot more narrowly than you intended it,
the criteria.
MR. McCARTIN: What, the --
VICE CHAIRMAN WYMER: The adequate
characterization and propagation of data uncertainty
seems fairly specific.
MR. McCARTIN: Sure. Well, it's looking
at the -- primarily, the parameter uncertainty. Have
you specified the ranges for these parameters
appropriately? Is it properly reflected? And do we
see that all the way through the -- at the end, the
dose variation is consistent with the uncertainty in
these parameters, etcetera?
VICE CHAIRMAN WYMER: My view is that it
expands explosively.
MEMBER GARRICK: No, no.
MR. McCARTIN: Hopefully not explosively.
CHAIRMAN HORNBERGER: John?
MEMBER GARRICK: I only have one question,
and I only want a two-minute answer. Can you remind
me, Tim -- and I should know this -- where the 10-8
per year threshold came from?
MR. McCARTIN: Well, that was in Part 60,
and we adopted that from Part 60. And I will go back
-- I can't give you the rationale off the top of my
head.
MEMBER GARRICK: Is there a connection --
is there a threshold in damage level associated with
the number?
MR. McCARTIN: I'd have to go back to 60
and resurrect the basis. I can't --
MEMBER GARRICK: Because if there is, you
know, Milt's comment is very relevant here in this
whole business of what constitutes adequate safety or
safety.
MR. McCARTIN: Well, I think there was --
remember, 10-8 was one in 10,000 over 10,000 years.
MEMBER GARRICK: Right.
MR. McCARTIN: And so I know qualitatively
there was some sense of what kinds of things might
happen over 10,000 years. And so it was a 10-4
probability with some --
MEMBER GARRICK: Yes, I know that. But it
has to be related to some level of consequence.
Otherwise, you're into a morass of analysis that --
MEMBER LEVENSON: You wouldn't use the
same number for somebody breaking an arm versus
killing a hundred people.
MEMBER GARRICK: Well, I wanted a two-
minute answer, and we've already gone three.
(Laughter.)
But we can solve that problem.
MR. McCARTIN: Yes. I'll get back to you
on that one if there is some more illuminating words
in the -- back from the --
MEMBER GARRICK: Yes. Because it's a very
casual statement, and yet behind the statement is a
potential analyst nightmare.
MR. McCARTIN: Sure. Now, the other
thing, 63 does give the caveat that something that
isn't going to have a significant effect on the timing
or magnitude of the dose does not have to be included.
So we're not saying go down to 10-8 for everything.
It's just things would have to have some type of
material effect.
CHAIRMAN HORNBERGER: Unless there is some
burning question from somebody, and it has to be a
short burning question -- Latif?
(Laughter.)
MR. HAMDAN: Tim, a very short question.
One site attribute that DOE has cited many times, and
you cited this morning, is the limited amount of water
protecting the waste. And yet on Tuesday DOE told us
that the amount of seepage is not important to the
process. It's the humidity and the chemistry of
seepage, and I believe that the TPA report essentially
is coming to raise another conclusion.
So how -- are we going to rethink this
attribute, or reword it, or --
MR. McCARTIN: Well, I --
MR. HAMDAN: -- in view of the findings?
MR. McCARTIN: -- I think it's still true.
The humidity -- the corrosion rate is sensitive to the
humidity, not to the seepage. And in that context, I
totally agree. However, intuitively, I have yet to be
convinced that the amount of water contacting the
waste doesn't have a material effect on how much waste
is transported away.
And it does matter. It's certainly -- for
something like neptunium where there is, you know, a
lot of it, and it's somewhat solubility limited, the
more water that contacts, the more neptunium will move
away.
CHAIRMAN HORNBERGER: Okay. What I'd like
to do, Pat and Jeff, if it's okay, is take a 15-minute
break. Okay.
(Whereupon, the proceedings in the
foregoing matter went off the record at
10:20 a.m. and went back on the record at
10:37 a.m.)
CHAIRMAN HORNBERGER: Let's reconvene the
meeting. We're continuing with our presentation on
the Yucca Mountain review plan, and Pat Mackin is our
next speaker.
MR. MACKIN: Good morning. Can you hear
me okay? Is my mike working? All right.
Jeff Pohle and I are going to talk about
a couple of subjects that are addressed in the Yucca
Mountain review plan, because they're addressed in the
regulations, that sometimes have confused people as to
how they relate.
I'm going to discuss safety questions, and
Jeff is going to discuss the performance confirmation
program.
The issue of safety questions is one
that's common to a lot of NRC regulations, and it
deals with the potential that at the time of a given
licensing step there are safety questions remaining.
These are different from performance confirmation
issues. These are areas where research and
development might be required to verify the adequacy
of design, for example. So, in other words, something
that people are not sure of yet.
Since this is an area that is somewhat
vague at this point, our acceptance criteria are also
designed to enable us to flexibly assess a number of
different situations. And these bullets here
represent the acceptance criteria that are outlined in
the Yucca Mountain review plan for safety questions.
The first one is pretty straightforward.
It's if there are any at the time of construction
authorization, have they been adequately described and
identified? Has a technical basis been provided? Is
it clear what the question is, and that it relates to
safety or to waste isolation?
The second one, then, is, how has DOE
proposed to address any such questions? Or what is
the technical basis for their plan to resolve the
question? And, again, it's kind of a little bit
difficult to talk about in the abstract. There are no
currently identified safety questions. That won't be
determined until such time as our licensing decision
and licensing review is to be made.
The next acceptance criterion fits in
pretty well with the nature of a safety question,
which is, what's the schedule for resolving it? If
the Commission agrees that a safety question can
remain at a particular state in licensing, that would
have to be resolved by some specific time, so you
could support the receipt and emplacement of waste.
So it's not an open-ended thing. It's
something that has to be closed out at some point.
MEMBER GARRICK: Pat, are we talking about
safety here in the same way we were talking about
safety earlier?
MR. MACKIN: Yes.
MEMBER GARRICK: Okay.
MR. MACKIN: These questions would be
related -- the important to safety or to waste
isolation.
MEMBER GARRICK: Okay.
MR. MACKIN: As defined in Part 63.
The next one would be, if the Commission
would agree to go ahead with some safety questions to
be addressed, are there alternatives in the
construction or the operation of the design that would
have to be considered to allow for that question?
And, finally, and the most important, I
believe, of the acceptance criteria is, if there are
any such questions, the staff will need to make a
recommendation, based on their overall integrated
effect on the construction of the repository, whether
it's appropriate to go forward with the construction
authorization or not.
And since that decision was based on --
would be based on the number and nature of any such
questions, we have not attempted to lay out any
specific criteria for how that judgment would be made.
And, again, by its nature, this particular aspect of
the review plan is focused on items that are important
to safety or to waste isolation. The acceptance
criteria you can see are fairly generic.
I've been asked to give an example of what
such a safety question might be, and I'll do so only
with a bunch of caveats. And one is --
(Laughter.)
-- there are no such formally defined
safety questions. That's a premature thing. And,
therefore, what I'm going to suggest is just a what
if. It's not something that's going to happen
necessarily.
But one might be, for example, that at the
time of construction authorization there are questions
about the stability of the underground facility when
it's constructed that cannot be resolved without
further digging and making of tunnels and analyzing
and mapping and measuring and things like that.
The Commission could consider, based on a
DOE plan, for further underground excavation,
monitoring, measuring, experimentation, that it would
be okay to go ahead with construction while this
further investigation continues into the development
of the underground facility.
It's clearly important to safety. It's
something at which the Commission might say, given the
circumstances at the time, it's okay to proceed, given
that you've given us a schedule and a plan. Of
course, but there may be a license condition that they
would not be allowed to go beyond some certain point.
Or, certainly, receiving and placement of
waste couldn't take place until this question were
resolved. But that is an example of the kind of thing
where there is -- it's different from a performance
confirmation item, where something has been used to
make the safety case, and now the Department of Energy
is confirming that the repository is performing in
that manner. This is something where there is a
question that isn't answered related to safety.
Does that help at all with what the nature
of these things might be if there were to be any at
that time?
And, again, this is the last bullet on my
presentation is these are different things from what
performance confirmation is intended to do.
Pending any questions, that's all I was
going to say about safety questions, and Jeff Pohle is
up next.
CHAIRMAN HORNBERGER: John?
MEMBER GARRICK: Yes. So these are safety
questions that were not otherwise considered.
MR. MACKIN: I don't know if "not
otherwise considered" is the full scope of it. It
might also be things that were considered and
addressed, but at the time of the license application
were not fully answered.
MEMBER GARRICK: Oh, I see. But I was
thinking of -- I thought I heard you say that may have
come up and that they'd turn out to be outside the
performance assessment, or what have you. So this is
more of a degree of resolution.
MR. MACKIN: Right. In this case, in
fact, this issue of underground stability would have
to be addressed both in the preclosure safety
assessment and, I assume, for the postclosure
performance assessment.
MEMBER GARRICK: Yes. And I guess if --
what it really does is allow some flexibility to deal
with these problems, given that there's a long
preoperational period or pre --
MR. MACKIN: Well, I think it becomes a
really -- I don't want to speak for the staff here, of
course, but I think it becomes a really tough
judgment. This is not meant to be a place you can
dump things, a bunch of stuff that you just haven't
had time to finish. There's a lot more thought than
that that goes into it.
MEMBER GARRICK: Yes, that's what I'm
trying to understand.
MR. MACKIN: And I think a decision to
allow a construction authorization with a safety
question remaining would be a difficult one and a
well-documented one, both by the staff and the --
MEMBER GARRICK: But it's not out of the
question.
MR. MACKIN: It's not out of the question.
MEMBER GARRICK: Right.
MR. MACKIN: And my understanding and my
experience is other NRC regulations or other programs
also deal with these what they call unresolved safety
questions.
MEMBER GARRICK: So it's not unique, then,
to 10 CFR Part 63.
MR. MACKIN: Right.
MEMBER GARRICK: Okay.
CHAIRMAN HORNBERGER: More questions?
Milt? Raymond?
Pat, this probably -- this question
probably doesn't fit under this particular topic,
although I'm not sure where it does fit.
You're probably familiar with the BRWM
1990 booklet "Rethinking High-Level and Disposable
High-Level Waste." And in there an approach is
described -- well, one of the issues is that with all
of the experience we have with mining, one thing we
know is that there will be surprises.
How do surprises in the construction phase
get dealt with by the NRC?
MR. MACKIN: There is --
CHAIRMAN HORNBERGER: It's not here,
right?
MR. MACKIN: No. There are requirements
in 10 CFR Part 63. And, in fact, as I understand,
there will be license conditions, if the construction
authorization is granted, for the DOE to report
periodically on the progress of construction and to
report any -- discovery of any items that would be
important to safety that were unexpected.
So my understanding of that is that that
would be a continuing focus of not only the NRC
inspection program but interaction with DOE then as a
licensee during construction.
CHAIRMAN HORNBERGER: Yes, okay. So, I
mean, what triggered that in my mind was the example
you gave with all of the caveats strikes me as
something that could happen without DOE anticipating
it ahead of time and identifying it.
MR. MACKIN: In this case, though, to take
that example, stability of the underground facility is
an item of focus both by DOE and the staff.
CHAIRMAN HORNBERGER: No, I realize that.
But, again, for your example to make sense, it would
be something that might be anticipated that would be
different with the rock in the proposed repository
area versus the experience otherwise, and --
MR. MACKIN: The part of the regulation
that deals with that I believe uses the term
"unexpected conditions." Is that correct, Tim?
MR. MACKIN: Yes. Yes, 63.32 talks about
conditions for construction. It gets into just the
things Pat is talking about. I mean, there is a
vehicle for DOE to update things, requirements of when
they have to report things to us, and schedules,
depending on what occurs.
CHAIRMAN HORNBERGER: Okay. Thank you.
MR. MACKIN: Thank you.
Jeff?
MR. POHLE: Can everybody hear me okay?
Microphone working? All right. Is that any better?
Performance confirmation. There are only
three slides on this topic, and these slides would be
suitable for giving an overview of how Part 63 is set
up, because it's pretty much identical with the
organization of the section in the review plan that
deals with performance confirmation.
The first slide is essentially some
background, straight out of the rule, the test
experiments and analysis used to evaluate adequacy of
information. And this particular requirement is
unique to the high-level waste program. It's kind of
a first of a kind.
And, basically, it was done in recognition
of the uncertainties that exist in these long time
periods that we're dealing with with the geologic
repository. And, fundamentally, that the performance
confirmation is intended to focus on natural and
engineered -- here I call it systems and components --
you could interchange the word "barriers" in here --
that are important to performance.
This is like -- the program is essentially
a confidence builder, somewhat similar like we have a
requirement for multiple barriers. In addition to
that, even though much work has been done in
characterizing the site and designing the repository,
certain testing and monitoring will be required all
through the other steps of the licensing process all
the way until permanent closure.
But the focus -- our intended focus would
be on the barriers, and then that is all laid out in
the acceptance criteria.
Now, the Subpart F of Part 63, which is
the performance confirmation program, is -- and the
review plan -- is laid out basically in the four bins.
There are four main requirements. One is the general
requirements, then dealing with geotechnical and
design parameters, design testing, and on the next
slide deals with the waste package. And most of these
ticks under here are basically items in the
regulation.
Now, these four items represent the areas
of review, so the review plan will be set up for each
area of review. There will be review methods and
acceptance criteria, and ultimately leading to the
final determination.
Now, at this point, when one starts to
review the performance confirmation program, Tim
earlier today in the section of the postclosure
performance called system description and multiple
barriers. Tim basically said, "While this is
something we would want to read first to get the broad
overview of the safety case, presumably DOE would
write it last."
Well, now, when we're at this point, this
is something we would read last and it would probably
really be written last on DOE's part, because it
should fall down from the safety case, the performance
assessment, leaving you to develop what components of
the barriers would be included in the performance
confirmation program for continued monitoring and
testing during construction and operation.
A couple of points to highlight. A couple
of sentences here right out of the rule, conditions
are within limits assumed in the license application.
Natural and engineered barriers are functioning as
intended and expected.
We would expect the rule of common sense
to apply. In the past, some concerns about these
particular sentences in the rule were brought to my
attention. Well, what does that mean? And let me
give an example.
Let's say in performance assessment for --
this is purely hypothetical. There is really no need
-- we have evidence. We know that, let's say,
groundwater would flow fast to the unsaturated zone.
Let's say hundreds of years. So in a performance
assessment, it may not be necessary to include that
time. We could assume an instantaneous release to the
water table.
Well, in reading Part 63, it would not be
our expectation that DOE would have to go out and
demonstrate that the travel time is zero. Is that
what was used in the PA? No. Common sense says you
may go back and continue to evaluate whether the
evidence, i.e. short travel times, that you use to
make that assumption in your performance assessment is
adequate. Okay? That's kind of how it would work.
MEMBER GARRICK: Before you move that
slide, will you say a few things about the tick that
talks about "includes in situ monitoring and in situ
experiments in laboratory and field testing"?
MR. POHLE: Right. That's a requirement
in the regulation that doesn't prescribe exactly what,
but merely that the program shall be composed of --
shall include in situ monitoring, in situ experiments,
that's in place in laboratory field testing in
general.
MEMBER GARRICK: There's a lot of emphasis
on the barriers. But that's -- well, that's why I
picked on that one, but that doesn't exclude a
monitoring program that is heavily oriented towards
phenomenological issues. That's what the laboratory
and field testing --
MR. POHLE: Yes. There would be no intent
here to be exclusionary.
MEMBER GARRICK: Pardon?
MR. POHLE: We would have no intent here
to --
MEMBER GARRICK: Okay. What I was getting
at is, in WIP, for example, it's very important to
measure certain things. It's a different natural
setting to be sure, and the time constants are very
much different. But you want to know about thing like
humidity and creep rate and closure conditions and
slumping off the rooms, and what have you.
And, of course, the barriers there are
much simpler, and it's not the issue that it is here.
But the emphasis there is more on process measures and
process confirmation than it is on hardware, for
example. And I just wanted to be sure that I
understood that the processes are also a part of this.
MR. POHLE: Right. Some months ago there
was -- DOE had a workshop on performance confirmation,
and I think the question arose, as an example, what
about climatology? Not that one would need to have a
specific program, but this type of thing should -- the
experts in the project should just be up on the
literature should something arise that would need to
be factored in to an update of a performance
assessment.
And we -- you know, the regulation would
not preclude that. So there are lots of processes
that could come into play.
MEMBER LEVENSON: I guess I've got a
little problem with the example you gave. They use
zero time. You say they don't have to prove it's zero
time, but you would expect them to periodically assess
the data on which the zero time is based. And I don't
understand why you have such a requirement.
MR. POHLE: No, there is a -- there is
two. And in the acceptance criteria in a review plan
there are two items that are always next to each
other. One is that those things you want to include
in a performance confirmation are important to
performance. And, two, if there are things that are
important to performance that you are not going to
include in the program, you need to give us the
rationale why.
Maybe it's the existing information gives
-- there's a consensus that it's of sufficient
certainty nothing more needs to be done would be
potentially basis for not continuing work on it.
Okay? So that, in a sense, I try to deal with that
hypothetically when I work the review plan. Some
things may be important but not be included in the
program.
Someone could make that case to us or that
argument to us. How would I deal with that argument?
And what would my basis be for saying that's
acceptable or not?
MEMBER LEVENSON: Do you mean you would
expect that people would have to defend the assumption
that there is zero retention or delay?
MR. POHLE: No. That they merely
understood how the unsaturated zone would function.
And that would be the basis for deciding how to deal
with that in the performance assessment.
MEMBER LEVENSON: I'm not --
MR. POHLE: But it may not be necessary to
do that if the knowledge was sufficient.
MEMBER LEVENSON: If it's something I'm
not going to take credit for, you want me to
essentially prove that it's okay to ignore what might
be conservative?
MR. POHLE: Well, that wasn't the intent
of that example. It was merely to show that --
MEMBER LEVENSON: Well, that's the example
you picked.
MR. POHLE: Well --
(Laughter.)
-- but it was in the context of our
functioning as intended and expected, not as an
example of what's important to performance.
VICE CHAIRMAN WYMER: I suppose it's
implicit in this that if the actual conditions are not
open to limits assumed with the license application,
you shut the thing down. Otherwise, you wouldn't --
there's no sense doing the performance confirmation.
MR. POHLE: That's always the potential.
Retrievability is always an option, right until the
time of permanent closure.
MEMBER LEVENSON: I hope you appreciate
that my question was stimulated by Commissioner
McGaffigan's questions.
MR. POHLE: In a sense, retrievability
would be a performance requirement in a broad sense
that would be considered in performance confirmation.
Like the previous example, you start construction on
the ground and you -- something comes up, you either
have to change the design so that the waste is
retrievable, or, if that's not possible, it's
irretrievable, you've reached that point where the
rule requires retrievability, you'd have to deal with
it.
Now, included under the general
requirements, the program is going to have to deal
with a bunch of administrative procedures, and now
you're getting into reporting requirements which will
have to relate to other parts of Part 63. You learn
something that's beyond some acceptable limit that
could require DOE to go into some design control
process and make a decision.
Does a design change need to be made? And
if it rises to some certain level or -- that would
initiate reporting requirements to the NRC to get
involved and possibly amendments to the license or
construction authorization.
VICE CHAIRMAN WYMER: On the next-to-the-
last thing on your slide, the backfill question in
compaction.
MR. POHLE: That's if backfill is used.
VICE CHAIRMAN WYMER: If it's used.
MR. POHLE: That's in the rule. In other
words, if backfill is used, it's actually in the rule.
And the last bin is the last requirement
in Subpart F that deals with monitoring and testing of
waste packages, and these are requirements in the rule
-- representative environment, laboratories are
focused on internals, and it continues up until the
time from permanent closure.
And so all of the review methods and
acceptance criteria would be related back to the
specific requirements in Subpart F.
VICE CHAIRMAN WYMER: Is there a reporting
requirement to the NRC on these performance
confirmation studies?
MR. POHLE: My expectation would be that
the procedures laid out or referenced in the
performance confirmation plan would reference the
other parts of Part 63 that specify what the reporting
requirements are for all --
VICE CHAIRMAN WYMER: Okay.
MR. POHLE: -- things that arise.
VICE CHAIRMAN WYMER: Okay.
MEMBER LEVENSON: Would you think that
this monitoring and testing equipment might be
categorized as important to safety?
MR. POHLE: Could you explain that
further? The monitoring and testing equipment?
MEMBER LEVENSON: Well, you're going to do
monitoring and testing. That's going to require
equipment. Would you consider that equipment
important to safety?
The context of the question -- the next
question is going to be that the review plan requires
that stuff that's important to safety -- this is the
exact wording -- requires it to perform for the entire
life of the facility without any remedial action.
They don't have to maintain it, repair it, or do
anything.
MR. POHLE: Well, I suppose there would be
two aspects of that, both the preclosure and the
postclosure. I don't think the postclosure would be
germane in terms of functioning, because the program
would terminate at permanent closure.
As to preclosure, perhaps, but I -- the
one -- the only related requirement in the rule would
be that the repository should be designed to maintain
the retrievability option. And that's in the post --
preclosure requirements section.
Now, that being, in a sense, a design
requirement would seem to me logical that any design
requirement would have to be run through the safety
questions, or whatever safety analysis, what is done.
Now, where one goes from there, I don't know.
MR. MACKIN: Excuse me. Could I ask a
question? When you say -- where are you quoting from
saying that equipment must operate for the lifetime?
MEMBER LEVENSON: Well, in the version
that I have, that's on page 4.1 -- Section 4.1,
page 57. In the bound version the pages are slightly
different, so it might be 56 or 58.
MR. MACKIN: Because the administrative
and programmatic requirements that are addressed in
the review plan specifically address the maintenance
programs, testing programs, monitoring programs, for
equipment important to safety. I'll have to read
that, but there is certainly no intent that systems
important to safety don't require maintenance.
MR. McCARTIN: Jeff, I guess if I could
add one thing, in terms of important to safety, it's
important to meeting those requirements. The way I
would read the rule, it doesn't say "and also to
confirm." So I think it isn't necessarily -- the
performance confirmation program doesn't necessarily
become important to safety. I mean, we can look at it
closer, but it -- just because you're doing confirming
of, say, the waste package, that confirmation I don't
think just becomes important to safety by definition.
At least --
MR. POHLE: I would say a context, though,
of -- it's an active program. People are doing things
that if that comes into play -- you know, worker
safety, in that environment --
MR. McCARTIN: Oh, worker safety. sure.
MR. POHLE: -- that will have to be dealt
with.
MR. McCARTIN: Yes.
CHAIRMAN HORNBERGER: Other questions for
Jeff? Jeff, I guess on this slide you have it as well
performance -- well, no, okay. It was on a previous
slide. Oh, no, there, the very last one. Monitoring
and testing will continue up until the time of
permanent closure. Presumably, this doesn't preclude
monitoring postclosure.
MR. POHLE: No. But I would not put that
in the performance confirmation chapter.
CHAIRMAN HORNBERGER: No, no. That's
right. It wouldn't be in the performance
confirmation. Right, I agree.
But I guess the questions that we saw
earlier this morning I think -- I asked Jeff a
question that looks like there is a requirement for
postclosure monitoring, and it would seem to me -- it
strikes me that somehow there must be at least a
recognition that the two might not be disjunct.
MR. POHLE: Well, I mean, fundamentally,
I don't think the postclosure part has been
necessarily thought through beyond permanent markers.
Did that come out of NWPA? Post-dating or original
Part 60?
MR. McCARTIN: I might it might have.
But, I mean, we certainly have a requirement that DOE
has to have a plan for post-permanent closure
monitoring. That plan could be here's -- we're going
to continue these types of things we have been doing
under performance confirmation.
But Jeff is correct. We wouldn't do it
under performance confirmation. It's a different
program. We have left that right now very flexible
for just the reason that post-permanent closure
monitoring is probably a minimum of 100 years from
now, and it would be somewhat folly to try to put
anything other than a very general requirement that
DOE needs to plan for this.
MEMBER GARRICK: But it still could be
considered performance confirmation or performance
monitoring. After all, a performance assessment is --
MR. McCARTIN: Well, in philosophy,
philosophical terms, yes, you could. But because the
rule has a very particular purpose for performance
confirmation which goes to closure and stops --
MR. POHLE: The amendment for permanent
closure.
MR. McCARTIN: Yes.
MR. POHLE: The last update of the license
application and performance assessment.
MR. McCARTIN: Yes.
MR. POHLE: And I guess I could have
mentioned earlier under the plethora of administrative
parts that will have to be dealt with, the changes of
the performance confirmation program in progress, or
procedures will have to be developed and incorporated
into the plan and reviewed dealing with that, tests
terminate, new tests could start, the thing would be
a living type of a program, I'm sure.
MEMBER GARRICK: But I think performance
monitoring, if we want to call it, rather than
performance confirmation for postclosure, we certainly
don't want to restrict our thought processes to
markers.
MR. POHLE: No. I know we have a zero
restriction. I mean, there's --
MEMBER GARRICK: Right.
CHAIRMAN HORNBERGER: One of the things
that occurs to me, and the reason that I don't see how
this can be totally disjunct, is that if you were to
treat it that way, then performance confirmation --
everything ends, you know, at the end of a -- at
closure.
But by the same token, you have this
requirement for a plan. Now, if the plan, then, comes
forward to have instruments, in situ monitoring, and
nobody has done the testing that would give some
confidence that the instruments could perform in a
radiation field, what would the plan mean?
MR. POHLE: I agree.
CHAIRMAN HORNBERGER: I mean, I'm not
suggesting that that would --
MR. POHLE: It would be difficult enough
just up until the time of permanent closure.
CHAIRMAN HORNBERGER: Absolutely.
MR. POHLE: Much less at some unspecified
time period beyond that. I mean --
CHAIRMAN HORNBERGER: I mean, on the other
hand, if the postclosure monitoring is markers and
biennial sampling of wells in Nye County -- other
questions?
MR. McCARTIN: I guess in that sense, I
mean, there is a recognition that your ability to
retrieve is going to go away. I mean, that's the
concept of closing it, and so the post-permanent
closure monitoring is more -- I don't -- it's
confirming a part of the repository, but it could be
very simple that, are there releases occurring?
Period. That --
CHAIRMAN HORNBERGER: But the releases
where, Tim?
MR. McCARTIN: Well, yes, it might be the
saturated zone.
MR. POHLE: Well, there's no more decision
points even in the regulation beyond permanent
closure.
MEMBER GARRICK: According to our former
member, who was a mining engineer, he says the option
to retrieve never goes away.
(Laughter.)
MR. POHLE: Well said.
CHAIRMAN HORNBERGER: Other questions or
comments? No?
Okay. Thank you, Jeff.
We take it that you're a Larry Campbell
stand-in, Pat?
MR. MACKIN: Right. I have been asked to
present this information for Larry Campbell, and I am
not qualified to do so.
(Laughter.)
CHAIRMAN HORNBERGER: Your presentation
has been quality assured?
MR. MACKIN: Yes.
(Laughter.)
When we started preparing the Yucca
Mountain review plan section dealing with quality
assurance, we had somewhat of a dilemma because the
question was, how do you make it risk-informed,
performance-based? And so what we did was -- what
Larry Campbell did was to say, "We have to be ready to
both evaluate a non-graded QA program and a graded QA
program."
So the Yucca Mountain review plan needs to
be flexible enough to deal with whatever DOE sends to
us in any license application.
And then, as I say on the viewgraph, in a
non-graded program everything would be afforded the
same quality controls. In a graded QA program, you
could vary the level of quality controls, varied based
upon the significance of a structure, system, or
component to safety or to waste isolation. And that
is one way in which risk significance comes into the
QA portion of the Yucca Mountain review plan.
One of the things that the Yucca Mountain
review plan requires is that you read through what
will be an interface between the quality assurance
staff and the other technical reviewers for the
purpose of making sure that the assessments of the
degree of importance to safety are appropriate and
that the appropriate level of controls are applied.
In going back to Banad's presentation
earlier this morning, there is what we believe is a
risk-informed process that identifies structure,
systems, and components important to safety. And that
would be the basis for what goes on the Q list, what
items fall under the QA program.
And if DOE applies such a graded QA
system, one of the things the staff would review is
the criteria they use to determine how they graded the
application of the QA requirements.
The last two viewgraphs just show the
areas that the QA program envelopes. In 10 CFR
Part 60, in Appendix B -- 10 CFR Part 50, Appendix B,
QA program, was called into play. In Part 63, we have
actually reproduced the language necessary for the
entire QA program, and it is basically a 10 CFR
Part 50 Appendix B QA program, with a couple of minor
changes that are shown as the last four items on the
last viewgraph.
Those are areas where quality programs
ought to be employed, which are somewhat unique to a
high-level waste repository. So criteria have been
added for those four areas.
Other than that, the approach is similar
to 10 CFR Part 50, Appendix B, and it acknowledges
that the staff will evaluate any graded program that
DOE elects to execute and the criteria they use for
that program.
Subject to your questions, that's all we
had to say on QA.
CHAIRMAN HORNBERGER: Thanks very much,
Pat.
Questions for Pat?
MEMBER GARRICK: Yes. I'm surprised that
-- maybe I'm not. I am familiar with 10 CFR 50,
Appendix A, Appendix B. I'm surprised that a quality
program that was designed for systems that were
99 percent hardware and mostly active systems would
have as much correlation with the kind of problems
we're dealing with at Yucca Mountain to be able to
adopt it pretty much in its whole form. And I guess
it's because the QA procedures are at a pretty high
level and very process-oriented.
MR. MACKIN: Well, I think also there are
aspects such as fabrication of the disposal
containers, the construction of the surface facility,
the equipment that will be used to emplace waste, all
of those things are subject to standard QA controls.
Plus, things like documenting the
geotechnical parameters, mapping the geology of the
underground facility. How do you control that
documentation? Are your instruments calibrated? All
those kinds of things. Actually, there is a great
deal of similarity.
MEMBER GARRICK: Well, in the preclosure
phase, and then in the emplacement phase, but with
most of the safety analysis effort being in the
postclosure phase, that connection is a little more
subtle.
MR. MACKIN: I really don't want to get in
too much trouble with Larry. But I think the way he
sees that is -- in writing this is that the engineered
barriers and the documentation and the justification
of the natural barriers that are important to waste
isolation all needs to be done under a quality
program.
Similarly, the development and use of
computer codes, tracing them, validating them, all --
as it applies to postclosure safety, all needs to be
under the umbrella of quality programs.
MEMBER GARRICK: Let me ask Tim a
question. Does the quality assurance program have any
impact, or is it accounted for in any way in your
waste package defects model? I mean, because that's
a very important contributor to the near-term
performance.
MR. McCARTIN: Well, in an indirect way,
I would say yes. But if you're talking about the TPA
code --
MEMBER GARRICK: Right.
MR. McCARTIN: -- what was done there was
they looked at, as best they could, some similar
manufacturing types of efforts, which certainly employ
some type of QA program to get a rate.
We have never touted ours as, "This is the
way DOE needs to go." We have, I don't think, any
problems with reviewing what DOE is doing in terms of
QA for the waste package in deriving a defective that
could be different than what we're using.
We did it in a very quick qualitative
sense for our code. But, you know, the burden isn't
really on ours, and so we haven't gone back to relook
at that. We certainly have seen what DOE has done,
and I think it is -- you know, there could be a much
higher level of quality assurance applied to the waste
package than was in our sort of generic look.
And so it would be appropriate, but we
would -- you know, we aren't -- we have not tried to
cast our, you know, I think it's a tenth of one
percent to one percent, or a tenth of a percent to a
hundredth of a percent as the number. But it was
something that --
MEMBER GARRICK: Yes. It just seems that
this is something we should be able to get a pretty
good handle on. And this whole juvenile failure
issue, that's not --
MR. McCARTIN: Yes, absolutely.
MEMBER GARRICK: -- that's not a long-term
problem.
MR. McCARTIN: Right, right. And I would
suspect that DOE will carry that forward in terms of
their QA and what number they can support in the
license application.
MEMBER LEVENSON: I've got a slightly
different question, based on the statement you just
made. And that is, how do you apply QA and validate
codes for volcanism, seismology, climatology,
etcetera, going out 10,000 years? Is that a paper
exercise, expending a lot of effort?
(Laughter.)
How do you do that?
MR. MACKIN: In fact, there are -- the NRC
has published guidance on the qualification of
software, and --
MEMBER LEVENSON: But there's a difference
between software that you can experimentally check.
MR. McCARTIN: Yes. If I could, you are
correct. I mean, part of it is that verification, and
some of the simple tests I know you've pointed to,
does the code -- is there a mass balance? And you're
certainly wanting to see some quality assurance for
the code is doing what I intended it to do.
Now, that's the verification. There is a
validation aspect to it. You also have to do -- you
need to do something as you've seen with our
regulations to justify that, indeed, this appears to
be a reasonable representation. And there are limits.
There is -- and I don't think there's
anywhere in our regulation we're asking the Department
to do the impossible. But there needs to be some
evidence, some support, for why you have adopted this
approach. And you need do that, and it's -- once
again, it's a sliding scale.
MEMBER LEVENSON: This might be a good
place to apply graded --
MR. PATRICK: Dr. Hornberger?
CHAIRMAN HORNBERGER: Yes, Wes.
MR. PATRICK: Wes Patrick here in San
Antonio. If I could add just one thing to Tim and
Pat's comments. This is an area where we feel very
strongly DOE can use natural analogues of both
existing systems and ancient systems and, to a degree,
Mr. Levenson, do some validation.
We've tried some of that ourselves to see
what the limits are, to make sure that we're not
requesting something that isn't possible to do. Two
very good areas are with regard to structural geology.
We have looked at analogue fields to get an idea of
whether there is a way to get support for how much
intrusive volcanism is -- or, I'm sorry, intrusive
igneous activity is associated with extrusive
volcanism.
I've also looked at analogue sites in
terms of how the ash is distributed from volcanoes
that are in the same relative energy of eruption.
In a third area, similar kinds of things
have been done with regard to natural analogues for
the dissolution of waste forms. And I'd like to note
in that regard that the Department of Energy is
currently looking at reoccupying the research site
that NRC used at Pena Blanca, Mexico, to try to get
some additional information in that regard.
It's not perfect, Mr. Levenson, but I
think it really is -- gives -- I would think helps
give a stronger foundation for those models.
MEMBER LEVENSON: You unfortunately used
a word which triggered a response, and that is you
said it's -- you're not asking for the impossible.
And since I'm sensitive to questions from
Commissioners, and we just had our experience
yesterday, I'd have to say that our objective is not
to ask for everything that's possible. Our objective
is to only ask for what's essential.
MR. PATRICK: I don't disagree with that.
CHAIRMAN HORNBERGER: Other questions?
Raymond? Staff?
Thanks very much, Pat.
Jeff is going to tell us some -- a few
concluding comments, but also tell us a bit about
schedules.
MR. CIOCCO: Right. We just concluded our
formal presentation. We've covered about --
CHAIRMAN HORNBERGER: You're going to have
to use a microphone, Jeff.
MR. CIOCCO: Oh, I'm sorry. I thought
this was on. Is it on? Okay. I can put it on my
chin. Thank you.
Okay. I did want to clarify one question
or one response I gave as far as the acceptance review
that Dr. Hornberger asked. And I went back to
Section 21, and it's clearly the intent and the
expectation that within the 90 days we will provide
the results to the Department of Energy of an
acceptance review, including any requests for
additional information. It will not be on the
critical path, and I think I misspoke earlier on that
point.
As far as the schedule, we certainly want
to leverage your knowledge and expertise as much as we
can in your review and commenting on the Yucca
Mountain review plan. And I kind of briefly earlier
covered what our schedule is, and just let me say it
again. We're currently printing up the NUREG,
NUREG 1804. They will probably finish distribution
this week, get all of their mailing -- the big mailing
campaign done.
The NUREG will be published, up on the
website. There's a nice site on the new external web
now for NUREGs -- NUREGs for comment. Once it's up on
the web, which will probably be later this week or
early next week, we'll issue a Federal Register notice
for a 90-day notice of availability and request for
public comments.
And I expect that to be dated around
April 1st. So we'll start a 90-day -- minimum 90-day
public comment period. So, and that's a 90 working
day. So April, May, and June. And we expect some
time probably in the middle of the public comment
period to go out and conduct public meetings in and
around Las Vegas, possibly the week of May 20th.
We're not exactly sure.
So that will leave the close of the public
comment period probably about the end of June. It
will take some time, depending on how many public
comments we get, to do our response to comments, do an
addendum to the NUREG, and that whole -- we will then
begin a finalized Revision 2, and then we need to send
that back up to the Commission. So some time this
fall or early winter we expect to do that.
So I'm just -- I'm trying to give you some
of the -- you know, an idea of what kind of timeframe
that the ACNW may be looking at as far as interactions
with staff to answer any of your questions and to get
as much feedback as we can before you write your
letter.
I know Dr. Garrick has an interest in
talking about the preclosure safety assessment ISA.
He wants to, you know, talk about this with some of
the staff, getting into some of the technical issues.
And in any areas that you would like to do that, we
certainly can do that now. We have a public document.
So that's really all that I wanted to
conclude with. If you have any questions for any of
us here, general questions or specific to the review
plan, feel free to ask.
CHAIRMAN HORNBERGER: I have one to start
with anyway. I just want to make sure that I'm
totally clear on this. I gather from all of the
presentations that your position is that your -- all
of your acceptance criteria are flexible. That is,
they are not prescriptive. Is that your position?
MR. CIOCCO: Well, they could be. That
was the intent. And we were given, you know,
direction from the Commission to make acceptance
criteria performance-based.
CHAIRMAN HORNBERGER: Right.
MR. CIOCCO: Give the potential licensee
performance criteria, and they have the flexibility in
meeting that criteria. And so that certainly was the
intention.
Now, there are some programs that are very
specific in the general information and physical
protection requirements in Part 73. There is not a
whole lot of flexibility. If you read the rule in
Part 73, there are certain setback distances. You
know, there's a lot of very specific areas. But in
preclosure and postclosure, that was certainly the
intent, yes.
CHAIRMAN HORNBERGER: Okay. Other
questions? John?
MEMBER GARRICK: Jeff, just so that I
don't deal with it elsewhere, if it's irrelevant or a
nonsensical issue, but one of the things that I kind
of looked for in this report was maybe some aids or
graphics that would add clarity to how this process
works. Is that something that's coming later in
guidance documents, or what have you? Or is it even
something that was considered?
Again, I'm thinking of I think from the
standpoint of understanding how this process works,
after you read about 200 pages and it kind of repeats
itself with -- just with respect to different types of
issues, you sort of see a rhythm and a structure that
probably could be communicated very effectively in a
well-designed activity network or some such thing.
Did you consider using any graphics in
this?
MR. CIOCCO: Yes, we did. Are you
speaking on the postclosure --
MEMBER GARRICK: Yes. I'm speaking
primarily of the postclosure.
MR. CIOCCO: Yes. I think we tried to do
as much narratively as we could up front in kind of
laying out the review process. And I know I've talked
some with our public outreach people recently, and
we're, you know, thinking about ways of communicating
the performance assessment process with some visual
graphics, how the review process would work at the
public meetings, and there's certainly a possibility
to put those in here.
There was no restrictions on what we
could --
MEMBER GARRICK: Okay. That was really
my --
MR. CIOCCO: -- as far as I'm aware. I
mean, we have the flexibility.
MEMBER GARRICK: But there's no
fundamental reason for why they were not included.
MR. CIOCCO: No.
MEMBER GARRICK: Yes.
MR. CIOCCO: No. No, it's certainly -- I
mean, if it's an aid to the reviewer, it -- if it's
helpful to the reviewer and to the public to
understand our process, then it's a good idea to put
in there.
MEMBER GARRICK: Thank you.
CHAIRMAN HORNBERGER: I think perhaps
particularly the public is our thinking. But as John
said, a picture with a thousand words isn't
necessarily the direction we want to go.
(Laughter.)
Milt?
MEMBER LEVENSON: I've got a little bit of
a general question. It's fairly clear, I think, that
some of this was put together using reactor experience
and background, because, for instance, in the section
on important to safety there are 10 references. Seven
of them are basically things coming from reactors.
How extensive or what kind of a review was
done to make sure that since this is a completely
different facility, completely different time
constants, completely different risks, that things
that are relevant to reactors and not to this facility
were not transferred over.
And I'll give you one example that I think
maybe got through your network if you had one. One of
the requirements is that you minimize the mass of
shielding materials subject to neutron activation.
That's a very good one in the reactor. I don't know
what its significance is in this system.
MR. CIOCCO: That's a good point.
MEMBER LEVENSON: Lots of requirements
were imposed that really aren't relevant to this
facility.
MR. JAGANNATH: Banad Jagannath, staff.
In the preclosure part, the fact that we had no time
to develop any of our own guidance, they are borrowed
heavily from what is existing, with a clear caveat
that had to be applied as appropriate for the cases
here. It was not a requirement that they are
applicable in full force.
The concept, whatever we can use within
the context and applicability of this situation, would
be used. And there is a lot of engineering judgment
both the staff and the licensee has to use in that.
That's where the flexibility is. It's just the
guidance for the staff to -- will do if the material
is there.
MR. MACKIN: Pat Mackin from the center.
I'd also add there that we did make a strong effort to
tailor the use of guidance that was for existing
programs. And there was no intent, I assure you, to
add things that weren't relevant. So if you find
those things, we're really interested in knowing about
them, because they aren't there on purpose.
MEMBER LEVENSON: Well, it seems to me the
answer of saying that there is flexibility to not
follow them, kind of raises -- brings into question
why you did this whole exercise. This is supposed to
be the guidance. And if it's -- if there are things
that -- flexibility depending on details of design is
one thing. But flexibility on areas as far afield as
neutron activation and shielding implies that there
couldn't have been a very tight screen if you screened
out irrelevant things.
MR. McCARTIN: You raise a good point.
And as Pat indicated, there is nothing in there that
we put in intentionally knowing that it was
irrelevant.
MEMBER LEVENSON: Oh, that wasn't my
question.
MR. McCARTIN: But we -- part of the
public review and our further review will look for
things that if they shouldn't be in there we want to
get them out, as well as the converse. There might be
some things we missed that need to get in there, but
you've identified one. I'd like to think there aren't
a whole lot of those, but we'll find out.
MEMBER LEVENSON: Tim, you know that I got
this a couple of days ago. You know, I didn't read
the whole thing.
MR. McCARTIN: Right.
MEMBER LEVENSON: But scanning it at
random, I can find a few. I have to assume there are
more.
MR. McCARTIN: Sure. Sure.
MR. JAGANNATH: This is Banad Jagannath
again. In developing the guidance, we have used the
approach of using all of the available reg guides,
guidances, and with a clear understanding it had to be
used as appropriate and as applicable for the case at
hand.
Some of them are not exactly made for this
one. This is requiring the staff to go look for where
it is available and use it appropriately.
MEMBER GARRICK: I think that's all right,
and you should do that, because we've also been
critical of the agency from time to time for the lack
of consistency in some of the rules and regulations
with respect to the different types of facilities.
But I think one of the things we're
hopeful that was done was that the experts on this
particular facility sort of sat back and thought about
what makes sense for a license review process. And
then sought out what you have in place that might be
relevant to that. That's what we're saying, rather
than letting what's been done in the back -- in the
background be the driver -- the only driver.
CHAIRMAN HORNBERGER: So what I hear is
that you would like to get rid of this kind of thing?
MR. McCARTIN: Absolutely.
CHAIRMAN HORNBERGER: Okay. Jeff, I have
a question on your planned public meetings. You
mentioned Las Vegas. Do you plan -- is your plan to
do something similar to what you did for Part 63?
That is, a series of meetings? Or is this just one
meeting in Las Vegas. How are you going to use the
experience you gained? And you gained a lot on
Part 63 in doing this.
MR. CIOCCO: Yes. I think, well, we're
kind of strategizing right now. But the intention --
and we have a public outreach group who is going to
help me plan this, I sure hope.
(Laughter.)
But the intention is is to do several
meetings around the Las Vegas area, perhaps
sequentially, you know, in one trip out there. But
there's not -- that wouldn't preclude us from doing
other meetings and certainly use whatever lessons
learned from the Part 63 experience.
CHAIRMAN HORNBERGER: Do you have any
plans to do a poster for a booth at the Geological
Society of America meeting, or anything of that sort?
(Laughter.)
MR. CIOCCO: Yes. They don't seem to let
me out of the office much anymore. But, yes.
Certainly, you know, public outreach for the review
plan is there are certainly many avenues that we could
explore in addition to the public closed meetings.
And public outreach is talking about poster boards and
fact sheets and whatever would help somebody
understand how the staff plans to review a license
application if one comes in. And we certainly
entertain those ideas.
CHAIRMAN HORNBERGER: Good. I'm glad to
hear that, because the ACNW was very impressed with
what was done for Part 63 in the public meetings and
in the public outreach activities. So I'm glad to
hear that you have some of these same folks helping
you.
MR. CIOCCO: Yes, we sure do.
CHAIRMAN HORNBERGER: Other questions or
comments?
Thanks very much, Jeff.
MR. CIOCCO: Okay. You're welcome.
CHAIRMAN HORNBERGER: Maybe we could take
at least a couple minutes for the committee to do at
least a very initial preliminary assessment of how we
want to proceed with our review of the Yucca Mountain
review plan, while this is all very fresh in our
minds.
It seems to me -- well, first of all, let
me just ask a question. Should we make an effort to
focus primarily on postclosure? Any thoughts? Just
a simple yes?
MEMBER GARRICK: Well, I think it should
probably be the emphasis, simply because that is the
thrust of the safety case. But I don't think we
should neglect anything. I think the one thing that
we really want to talk about and revisit is try to get
before us -- and it's in the report pretty well --
what was the real underlying and overarching drivers
for the review plan, and have our consideration of the
issues emanate from the -- something that's very
fundamental and basic. At least that strikes me as --
I'd prefer a top-down approach is what I'm saying.
MEMBER LEVENSON: I think I would agree
that we need to look at both parts but use the QA
terminology. Maybe we have a graded approach to --
MEMBER GARRICK: Yes.
MEMBER LEVENSON: For one thing, the
preclosure incidents that could happen in the facility
and above ground, etcetera, have such an infinitely
small source term compared to the total inventory in
the ground that the potential risk is significant.
CHAIRMAN HORNBERGER: So I think we'll
note that. We are certainly not going to ignore
anything, but the main focus would continue to be on
postclosure.
The second question I have is, do we want
to in some way -- again, not focused to exclusion --
but concentrate, for example, on the vertical slice
areas that -- or different vertical slices. Because
it strikes me -- Milt had sent me an e-mail, I think,
when we first got the Yucca Mountain review plan that,
to a certain extent, we're faced with some of the
similar problems.
Are we going to read it cover to cover and
try to comment in detail on everything? Or would we
gain some benefit by tracing from the -- I think one
of the original ideas that Lynn and I had many months
ago was that we would try to trace the evolution from
IRSRs to integrated subissues to the Yucca Mountain
review plan to basically inform our review in terms of
how things -- staff ideas and criteria have evolved.
MEMBER GARRICK: Yes, that's part of the
reason for my question about graphics.
CHAIRMAN HORNBERGER: Yes, right.
MEMBER GARRICK: Is that I think the more
we can put the picture together in some sort of
graphical form and see how all of these components fit
one with the other, I think the better we will be in
terms of being able to assess the effectiveness of the
plan. So we may end up doing some of that ourselves.
MEMBER LEVENSON: Yes. I think it just
isn't practical. I don't know about the rest of you
guys, but I don't have enough time to read this kind
of stuff. So we need some kind of sampling and non-
Andersenian audit system.
But I'm not sure that the vertical slices
we used before make sense, and it may be that we start
with some of the -- either the points Tim listed or we
select other things that we think make a logical basis
for following through. And, in fact, this has reached
a level of importance that maybe our sources are --
there are four of us that we don't have to pick our
vertical slices from the same source. Maybe a couple
of points from Tim, and a couple from IRSR, but I
think we need to evolve our audit plan.
MEMBER GARRICK: And I think one other
thought process that should guide what we're doing
here is that in the exercises that the staff has been
through through the technical exchange process, they
have already identified some very important issues,
such as, for example, model abstraction.
And I think we need to partly be guided by
what has been identified as the issues that were
surfaced during a sufficiency review exercise, and see
if we can be satisfied that this review plan is
thorough enough in regard to those kinds of issues to
get the job done.
So there's a number of things I think that
can sharpen our focus. You've mentioned the one --
namely, more emphasis on the postclosure. But I think
the issues that have already been addressed and
surfaced as primary could be another.
VICE CHAIRMAN WYMER: Yes, that was the
point I was going to make. I'm glad you made it,
John. I think that we have the burden of guiding
this. We ought to look at the 14 issues that are
being integrated and try to consider this review plan
within the context of postclosure and integration.
MEMBER GARRICK: That's right. I think
one of the biggest mysteries in this whole process is
the abstraction process. And I think if we could
satisfy ourselves that that was going to be
appropriately considered and dissected, and motivated
by this plan, that would be a very important finding
for us to make.
VICE CHAIRMAN WYMER: That's a mechanism
by which we can actually accomplish something.
MEMBER GARRICK: Right.
CHAIRMAN HORNBERGER: Okay. Now, perhaps
I've -- maybe I'm just confused, but I thought that I
just heard two contradictory things.
MEMBER LEVENSON: You did.
(Laughter.)
CHAIRMAN HORNBERGER: Milt suggested that
we can't do it all, and if we do all 14 subissues
then, in essence, that's what we're going to do.
MEMBER GARRICK: Well, I don't think we
should do all 14 subissues.
CHAIRMAN HORNBERGER: Okay.
MEMBER GARRICK: I'm thinking that --
CHAIRMAN HORNBERGER: I think that we're
really focusing on the process here.
MEMBER GARRICK: Okay.
CHAIRMAN HORNBERGER: And whether it's for
issue number 10 or issue number 11, we can be guided
on that by the analyses that have been done to date.
MEMBER GARRICK: Right.
CHAIRMAN HORNBERGER: And I think that
might be the strategy for assignments more than a
vertical slice.
VICE CHAIRMAN WYMER: I think the
important thing is the way the integration is handled
rather than the issues themselves.
CHAIRMAN HORNBERGER: Okay. So the
integration is the question, which is a question that
we have had, so I think that's correct. We do have to
make sure that we don't do whatever slice we do and
totally ignore integration.
Lynn?
MS. DEERING: Along that same line, if
you've followed the theme from yesterday's Commission
briefing, it was the two things you mentioned --
integration as a continuing concern. And it only
takes one example. You don't have to look at 14 ISIs
to worry about integration; you could look at one and
get there.
But also, risk insights, how those are
actually being applied in this process. If those were
-- just those two themes along could be a thread that
you've been following and --
VICE CHAIRMAN WYMER: I think we have to
look at all of them. But I think to pick up on what
Milt said earlier, use the graded approach. Some are
more significant than others.
MEMBER LEVENSON: In fact, Lynn, we might
apply what you have said, combined with the concern
about these 14 items. We might review one of these 14
items for how it's all integrated and put together,
etcetera. Pick another one and follow it through to
see how risk insights have been applied or impacted,
etcetera.
So that's what I meant by saying the four
of us might have four slightly different types of
slices.
CHAIRMAN HORNBERGER: John?
MR. LARKINS: I think there was another
issue that came out of yesterday's Commission meeting,
where Commissioner McGaffigan raised the question of
not only assuring this is risk-informed but also not
requesting too much information and having a
reasonable expectation standard now. What does that
mean in terms of acceptance criteria as opposed to
reasonable assurance? So that may be something that
you want to consider in doing this also.
MEMBER GARRICK: Good suggestion. I think
that is important.
MR. LARKINS: It wasn't clear to me, from
just scanning through the document, how things have
changed in terms of acceptance criteria in going from
one standard to the other. But I think it's something
we could talk to the staff offline about.
CHAIRMAN HORNBERGER: I think that's good.
Let's see, before we break, I just wanted
to ask Jeff if he had any particular -- Jeff or Pat,
would you like to point us in any particular
direction? Is there anything we've articulated you
would like to --
MEMBER LEVENSON: Or a direction you'd
like to point us away from.
CHAIRMAN HORNBERGER: Oh, yes.
(Laughter.)
Go ahead and tell us that. We won't
listen, but --
(Laughter.)
MR. MACKIN: I thought two things that
might be useful are at the beginning of each major
section there is a description of the approach we've
taken to try to make it risk-informed and performance-
based.
And as Tim mentioned in his briefing,
since the 14 model abstraction sections all use the
same five basic acceptance criteria, it kind of fit in
with what all of you were saying, is that you don't
have to look at all of them to see how, in general,
they've been constructed.
MR. CIOCCO: Yes. I think he's right.
That's certainly -- you certainly need to look at the
upfront information and how the whole -- for instance,
if you -- I mean, if you're interested in postclosure,
there was an attempt at front end -- some of that
resulted from our prior discussions with some of the
members on how the whole process is going to work,
just to keep that in mind. But no other further
direction.
CHAIRMAN HORNBERGER: What I suggest,
then, is that perhaps Richard and I could put our
heads together or through e-mail come up with some
kind of draft plan as to how we're going to proceed
and circulate that and get comments and try to iterate
on this. I think we have some good ideas now.
MEMBER LEVENSON: You might, again,
combine -- take the idea of checking the criteria and
pick one of the things in the 14 listed, and follow
that through. So a different one than the other.
VICE CHAIRMAN WYMER: That's one other
thought here. It's not as overarching as all of the
things we've been discussing, but let's pay some
attention to the definition of safety standards and
what would get to this question.
MEMBER LEVENSON: I have a question, which
I forgot to ask. In the review plan where you have
lists of all of the codes and standards and everything
that you expect to see followed, in the world of DOE,
what is conspicuous by its absence is all of the DOE
orders and standards, etcetera, which in some cases
conflict with the commercial codes and standards that
you have applied. Is there any significance to this?
MR. MACKIN: In think in general, in the
review plan where we listed codes and standards, they
were listed as examples and not as requirements, and
to show the types of documents that we thought
appropriate. There was no -- Banad, there was no
attempt to screen out DOE orders or anything there.
MEMBER LEVENSON: Well, not, but I -- but
the question is, since you did list them, is the
implication that the commercial standards would be
considered adequate by NRC?
MR. MACKIN: Yes. I think the general
philosophy is that DOE selects the codes and standards
they are going to use, justifies that they're
appropriate, and Part 63 presents no ruling in or
ruling out of any of those. And then demonstrates
that they use them properly.
MR. CIOCCO: That's correct. And I think
if you look in the preclosure section the codes and
standards really come under the review methods where
staff is going to review what the DOE has submitted.
I don't think under the acceptance criteria you'll
find the codes and standards. It's certainly up to
DOE to use whatever they feel is applicable, whether
it's a DOE order, an NRC NUREG guidance document. DOE
certainly has that flexibility.
CHAIRMAN HORNBERGER: Any other comments?
Questions? Clarifications? Apologies?
(Laughter.)
Okay. We are now going to -- we are then
going to break. We'll break until 1:00. We'll
reconvene at 1:00.
(Whereupon, at 11:55 a.m., the
proceedings in the foregoing matter went
off the record for a lunch break.)
Page Last Reviewed/Updated Monday, October 02, 2017
Page Last Reviewed/Updated Monday, October 02, 2017