467th Meeting - November 4, 1999
UNITED STATES OF AMERICA
NUCLEAR REGULATORY COMMISSION
ADVISORY COMMITTEE ON REACTOR SAFEGUARDS
MEETING: 467TH ADVISORY COMMITTEE ON
Two White Flint North, Room T2-B3
11545 Rockville Pike
Thursday, November 4, 1999
The committee met, pursuant to notice at 1:00 p.m.
DANA POWERS, Chairman, ACRS
GEORGE APOSTOLAKIS, Member, ACRS
THOMAS KRESS, Member, ACRS
ROBERT SEALE, Member, ACRS
JOHN BARTON, Member, ACRS
MARIO BONACA, Member, ACRS
WILLIAM SHACK, Member, ACRS
JOHN SIEBER, Member, ACRS
GRAHAM WALLIS, Member, ACRS
ROBERT UHRIG, Member, ACRS
. P R O C E E D I N G S
DR. POWERS: We will come into session. This is the first
day of the 467th meeting of the Advisory Committee on Reactive
Safeguards. During today's meeting, the Committee will consider the
following: proposed revision to Section 11 of NUMARC 93-01, Assessment
of Risk Resulting from Performance and Maintenance Activities; NRC's
safety research program report to the Commission; and proposed -- other
proposed ACRS reports.
The Committee met with the NRC Commissioners between 9:30
a.m. and 11:30 a.m. today in the Commissioners' conference rooms and
discussed several items of mutual interest.
This meeting will be conducted in accordance with the
provisions of the Federal Advisory Committee Act. Dr. John T. Larkins
is the designated Federal official for the initial portion of the
meeting. We have receive no written statements or requests for time to
make oral statements from members of the public regarding today's
A transcript of portions of the meeting is being kept, and
it is requested that the speakers use one of the microphones, identify
themselves, and speak with sufficient clarity and volume so they can be
I will begin the meeting today by bringing up a couple of
items of interest. Internally, effective November the 1st, 1999, Howard
Larson has been detailed to the position of Associate Director,
Technical Services of the ACRS/ACNW. I think everybody knows Howard.
Would you stand up? You may not know much about his background, which
is varied and rich.
During his career, he has had various leadership positions
in industry and government, having served as a nuclear-trained naval
officer; manager, reactor relations (**check word**) at GE's Vallecitos
facility; GE project manager for the Fitzpatrick plant; Duane Arnold
project manager for Commonwealth Associates; an
architect-engineer-constructor; director of engineering for General
Atomic; technical vice president for Atomic Industrial Forum, a trade
association; president and general manager for the Allied General
Nuclear Services, a reprocessing plant in Barnwell, South Carolina; and
Senior Vice President, Plant Services, for the Nuclear Energy Services,
DR. KRESS: He can't hold a job.
MR. LARSON: It's a lot of years.
DR. SEALE: Is there any significance to those suspenders
that he's got?
DR. POWERS: During a short tour of duty, during the
1974-1975 transition from AEC to NRC, he was the Director, Division of
Fuel Cycle and Materials Licensing, and the first Director of the Office
of Nuclear Materials, Safety, and Safeguards. Prior to assuming his
current position, Howard was a Senior Staff Engineer for the ACNW. So
we're getting a guy that has a excellent background for our kind of
DR. KRESS: A lot of mileage.
DR. POWERS: And even knows what goes on in the other side.
MR. LARSON: That's what my wife says.
DR. POWERS: Howard has possessed both Navy and AEC reactor
operator and senior reactor operator license, and is a registered
professional engineer in nuclear engineering in the State of California.
So, Howard, welcome aboard. And it looks like you bring a
rich and varied background to this Committee that we could learn a lot
from. I, myself, am always interested in what all goes on in the
Vallecitos in the past and in the present.
In the meantime, Dr. Savio has assumed the position of
Special Assistant to ACRS Executive Director. He's going back to doing
technical work instead of whatever it is that managers do.
Dr. Savio will work with Dr. Larkins to keep the Commission
informed on Committee activities--our operating plan, self-assessment,
et cetera. And he'll work with NRC senior staff on procedural and
policy issues impacting the ACRS and ACNW. And this self-assessment
business is, of course, an important activity that the Commission
assigned to us. And, Dick, I think you'll be helping us on that
As always, Dr. Savio is available to work with ACRS members
on issues that they need help on, and that's one of the ideas of having
a senior engineer here is that we can augment activities that sometimes
are done by fellows to pursue things in more detail than we might
ordinarily be able to pursue them in. And, Dick, I think you're going
to enjoy this job a lot. It's--
DR. SAVIO: Yes, I'm looking forward to it.
DR. POWERS: Yes, good. You also have a package of items of
interest before you. You may want to read some of the comments that
Commissioner Meserve had upon his induction into the -- his current
position. There are a variety of other things in this package that may
be of interest to you.
I have to wait. How long do I have to filibuster?
MR. SINGH: About another 10 minutes.
DR. POWERS: Another 10 minutes, right.
UNKNOWN SPEAKER: That's soup for you, David.
DR. KRESS: George? Where's George? Don't leave.
DR. POWERS: Well, I think that on that regard I want to
discuss a couple of things with the members. One of those is the
research report that we're going to prepare. Our objective there is to
have a report that is very nearly finalized at the end of our December
meeting so that we can take it home and look at it and give the last
final scribble (**check word**) of the holidays and actually put it out
officially at our February meeting. And I'm thinking that it might be
easiest to accomplish that if we have a subcommittee meeting of the
whole prior to our December full meeting to work on that research
report. So you might give some thought on the viability of that idea of
having a day prior to the full meeting to work strictly on the research
report, to get it in finalized shape.
The other item of -- that you should think about over the
course of the day is that Planning and Procedures has tasked Dr. Larkins
and myself to develop a plan for the retreat at the end of January. And
we have -- John has put together a first guess that you will -- of what
might be covered in that retreat. But I think you look at it strictly
as a draft. It's his first thinking on the subject, and might want to
think yourself about the topics that you think deserve the attention
during our retreat. I think clearly the issue of making Part 50
risk-informed will definitely occupy some of the time at least. Other
things, though, might be considered as well. And, John, do you have
anything to add to that?
DR. LARKINS: Yesterday, we talked about three or four
different topical discussions.
DR. POWERS: Right.
DR. LARKINS: And, you know, I'm not sure if those are the
only ones or the key ones that the Committee wants to cover, but, you
know, we'll go through those -- I don't have -- unfortunately, I don't
have it in front of me -- we'll go through those during the Planning and
DR. POWERS: Well, I have it. Let's see. Some of the
topics that have been suggested clearly the risk-informing Part 50;
standards for PRAs, as a discussion of what constitutes an adequate PRA;
discussions of computer codes and what constitutes the best estimate
code, what constitutes a good review of a best estimate code, what
constitutes validation of a best estimate code, thinking both of
phenomenological and risk assessment codes.
DR. LARKINS: And that includes a tutorial from Dr. Wallace
that we had put off a while.
DR. POWERS: That -- that would certainly be a central
element of this discussion.
DR. LARKINS: This is a strategy for reviewing these codes.
DR. POWERS: Another topic that's been suggested is safety
culture. What is it? Why is it important? Industry issues--what are
the issues that the industry have with NRC's regulations? What things
do they think deserve receiving attention? A self-assessment of the
ACRS itself, and development of its operating plan for the year. A
discussion of do we have the right members, enough members, too many
members, et cetera for the future.
DR. LARKINS: Yes, the issue on the ACRS interaction with
the industry is sort of a follow up to last year, where I think Dr.
Seale, Uhrig, and Mario Bonaca, and now Mr. Sieber would sort of
represent a panel to provide their insights on, you know, our
interactions with the industry, how we're perceived, and how well we
interact with them. And there's some -- some reports have already been
generated. I know Bob read a report a couple of months ago.
DR. POWERS: I think the strategy or the plans for this
meeting does include trying to complete this joint ACRS-ACNW letter on
background for risk-informing the regulations that apply to materials
licensees. When members get a copy of that, they want to look at it in
the understanding that we're going to basically vote yea or nay, and do
very little editing on that -- that letter. They are free to have added
comments if you want, but we're not going to go through and edit that
letter like we usually do. We presume that has been done by the joint
committee, and we're more in the approve it or disapprove it. But you
still have the right to have added comments if you want.
MR. SINGH: Staff is here.
DR. POWERS: Okay, so now we can move on with the -- first
item of business and that is the proposed revision to Section 11 in
NUMARC 93-01, Assessment of Risk Resulting from Performance and
Maintenance Activities. John, you're going to take us into this?
MR. BARTON: Yes, I will. Thank you, Mr. Chairman. The
purpose of the meeting this afternoon is to hear a briefing and hold
discussions with representatives of the NRC staff and members of the
industry regarding Revision Three, to Regulatory Guide 1.160, Draft
Guide 1082, with the title Assessing and Managing Risk Before
Maintenance Activities at Nuclear Power Plants and the industry's
document Section 11 to NUMARC 93-01, entitled Industry Guidelines for
Monitoring Effectiveness and Maintenance at Nuclear Power Plants.
We've had a recent meeting -- last month, month before --
with the staff and industry, and at that point there were three issues
that seemed to need resolution before we could move forward with the
regulatory guide. And those issues had to do with scopes in the
assessment, whether it's just high or low risk safety significant SSCs,
how they managed their risk, and the definition of unavailability. At
this point, I'll turn it over to the staff, Rich Correia, who will lead
us into, you know, where we stand with respect to the regulatory guide
and those outstanding issues.
MR. CORREIA: Thank you. Good afternoon.
Again, we're here to talk about the current phase version of
the draft regulatory guide for the change to the maintenance rule,
5065A4. I'm Rich Correia from NRR. With me today is Dr. See-Meng Wong
from the PSA branch of NRR. Bruce Boger, who is director of the
division of inspection program management, is my boss; and other
supporting staff here that will certainly chime in if requested.
If I could bring the Committee back in time a little bit.
We briefed the Commission on May 5th regarding rule making, and after
that meeting they directed us, through SRM, to continue working on the
rule revision and to begin work on the draft reg guide, seek guidance
from CRG-ACRS, and to work in a collaborative fashion with stakeholders
to produce a final regulatory guide for Commission approval.
I think the last element is really the focus of today's
briefing is the interactions we've had with NEI and industry on this
draft guide, the positions we had early on, and where we are today.
On May 17th, we delivered to the Commission the final rule
making package. We briefed the Committee--I believe it was July
14th--on where we were with the reg guide at that time. And shortly
thereafter, on July 19th, the rule was published to become effective 120
days after the guidance is finalized.
The rule itself, not very long--two sentences--essentially a
requirement to assess and manage any risk increases due to planned
maintenance activities. Currently, the rule has essentially the same
requirement, only it isn't a requirement--the word should is used. Long
story short, we recommended that the Commission change this rule to a --
to make this part of the rule, to make it a requirement. And very near
the end of the rule making deliberations, it was decided that this
particular part of the maintenance rule should have an element of a
risk-informed scope, which is what the last sentence is about--the
option to limit the scope of structure systems and components that are
risk-informed, the evaluation processes has shown to be significant to
public health and safety.
DR. SEALE: This is a band that you can fall on from either
direction. When you say the licensee shall assess and manage the
increase in risk that may result from the proposed maintenance
activities, that supposedly recognizes the configuration that the plant
is in for that particular maintenance activity?
MR. CORREIA: Yes.
DR. SEALE: So if that maintenance is being done -- and I
also understand that it has been the industry's position that the
maintenance rule covers shutdown as well as operating events?
MR. CORREIA: That was also a Commission-mandated change to
the rule to add a preamble that specifically states that this section
shall apply during normal operations and shutdown conditions.
DR. SEALE: So if I read those two statements together, then
I come up with a requirement that a risk assessment, based on the actual
plant configuration in the shutdown mode, will be the basis for
determining the risk importance of the relevant systems, structures, and
MR. CORREIA: We've taken the position in the regulatory
guide that if a licensee has a shutdown risk PRA, they should use it,
but we can't mandate it. So it would have to be accomplished using--
DR. SEALE: But you are saying here that they have to
recognize the risk significance--
MR. CORREIA: Yes.
DR. SEALE: Of SSCs based on the configuration that they're
in, and the mode of operation that the plant is in. Whether or not they
go through and do a formal risk assessment or not is a separate issue.
The determination of whether the component, or the SSC, is risk
significant or not risk significant is specific to the configuration and
the plant status?
MR. CORREIA: That's true.
DR. SEALE: I think we're there.
MR. CORREIA: That's true.
It is a dynamic situation. Yes, it is.
DR. POWERS: I think that the understanding that the speaker
has and the understanding that I think we have is the same.
MR. CORREIA: Yes.
DR. POWERS: But it's not clear to me that everybody shares
DR. SEALE: That's why I raised the issue.
DR. POWERS: And the magnitude of the effort associated with
doing the assessment I think is open to debate.
DR. SEALE: Yes.
DR. POWERS: And it is my belief that the rule, as now
written, and the guidance, as written, allows fairly easy threading
through one and two components out of service. Things get complicated
only when you go to more than two.
MR. CORREIA: That's true. Yes.
DR. BONACA: So regarding this statement, the last
statement--the scope of the assessment may be limited to structures,
system, and components that the risk-informed evaluation process has
shown to be significant to public health and safety. What does it refer
to? Ranking down by taking one component out of service at a time?
MR. CORREIA: No, the -- and I'll -- we'll get into this
briefly. The scope that we have determined that would meet this option,
because it is an option -- the licensees may chose to consider the whole
scope of the maintenance rule -- what we have determined is any high
safety significance system that's already defined for the maintenance
rule, any system that's modeled in the PRA, and certain other systems
that have either support high safety-significant or other PSA system
model in the PRA or have interdependencies with these other systems such
that they would have an impact on their performance--
DR. BONACA: So you're talking about those four items which
are defined in the guidance from NEI, the four conditions?
MR. CORREIA: We had four specific items in our draft reg
guide that has been translated by NEI into more of a process to
determine which SSCs should be considered during this assessment
process. They're not specific line items, but further discussion on how
you determine which of these SSCs need to be considered for the
DR. WALLIS: The thing that I don't understand is manage the
increase in risk, and because he's (**inaudible**) the maintenance
activities and he does his assessment and says that for 10 minutes
during this activity my co-damage probability is up by a factor of a
thousand. Do you expect him to do something? And how do you tell if
he's managed or not managed this increase in risk?
MR. CORREIA: We have to look at if he chooses to use a risk
assessment, what that risk value is, the process that he uses to take
actions to minimize that risk or reduce that risk through staff
awareness, contingency planning, having a back up or redundant systems
and people in place to manage the risk, control and--
DR. WALLIS: It's a kind of a catch all thing, though. I
mean, you're not specifying what he has to do. You just look at the
things that have been done, and say, yes, we think that was good
management or not.
MR. CORREIA: Well, the guideline does list several items
that should be considered. Yes.
DR. UHRIG: On certain utilities, they have a system called
the risk meter. Is it appropriate to perhaps run several combinations
of different activities at the same time to demonstrate that this is --
one way is better than another?
MR. CORREIA: Yes.
DR. UHRIG: Would this be an appropriate approach to this?
MR. CORREIA: Yes, it is.
DR. WONG: Yes, there are software -- PRA software that
contains a PRA model that will analyze the different configurations that
the plant may go into, and they will come up with risk numbers and some
of the -- what is being articulated in the guidance document and in the
NEI guidance document -- there are certain thresholds in which actions
need to be taken.
DR. UHRIG: This presumes that you have the PRA performed
for the shutdown condition included in the PRA, because you're dealing
with shutdown conditions here.
MR. CORREIA: Okay--
DR. WONG: Yes, in some of the -- my understanding is in the
risk monitor devices that are being developed today, they are
integrating shutdown risk models that has been developed so that you can
look across not only the full power operations but as well as in certain
modes of shutdown.
MR. BARTON: But you're not requiring a shutdown PRA?
MR. CORREIA: No. We strongly encourage it if they have it,
but we don't require it.
DR. APOSTOLAKIS: Let me try to understand this a little
better. Let's say we have a licensee who chooses not to use PRA, and
somehow a situation is identified where, indeed, the risk has to be
managed. Now, risk is kind of qualitative notion here -- that there is
some degradation of the safety functions. So they say, well, look, I'm
managing the risk. I am informing my people that we are in this
configuration, and they should be prepared to do certain things. And
the staff thinks about it, and they say, well, it makes sense to me. So
you're managing the risk.
Now, you have another unfortunate guy somewhere else who has
actually quantified the risk, and he finds also that the probability --
yes, the conditional core damage probability exceeds the threshold that
you have. And he says, well, I will make sure that my people know about
it and they will be prepared to do certain things so this probability
will be reduced, and the staff comes back and says, but these things
cannot be modeled in a PRA. You're in trouble. How can you show that
your -- that the threshold is not exceeded. So, all of a sudden, that
guy has to argue with you about the PRA and how the fact his people are
informed about something can change the numbers, and give and take can
take forever. Isn't that fellow penalized for using PRA? Then is that
something that we want to encourage?
MR. CORREIA: No.
DR. WONG: No, I don't they're penalizing people that are
using the PRA. You use the PRA to do a calculation as an input to your
decision that you're performing maintenance in a configuration.
DR. APOSTOLAKIS: But you see there is an extra question here
that you are not asking of the other guy. This fellow has quantified.
He finds that the number is eight ten to the minus seven, and you say it
should be five. So he says, well, he's proposing exactly the same
remedy as the other guy. And he says, you know, my people will be
alerted to this situation, and, you know, be prepared to do things. I
can see a series of exchanges between the NRC and the licensee here
arguing whether that particular provision will bring the number down to
ten to the minus -- five ten to the minus seven. Whereas the other guy
is completely free. The question doesn't even come up.
Now, from that point of view, it seems to me you're
penalizing the person who chooses to use a PRA.
MR. CORREIA: I guess I view it as the person -- well, if the
person -- if the utility or licensee doesn't have a PRA -- I'd -- my
view is he is much more limited as to what he can do to meet this
DR. APOSTOLAKIS: But does that come across? I mean, is
there a place where I can go and look and get that feeling?
DR. POWERS: I mean, suppose it's not this black and white.
Suppose we compare the guy with the PRA that has numbers to the guy that
has orange or he has colors, and he as three oranges and the rest greens
as his indicator, and another guy has one red and the rest greens. Now,
how do you respond to these -- we now have three people, all proposing
exactly the same change. One's got numbers. One's got colors that are
two -- three oranges and the rest greens. The other one has colors--one
red, the rest green. How do you treat -- what are the differences in
treatment of those three guys?
MR. CORREIA: In my view, a lot has to do with what other
actions they're taking, besides knowing the number or the colors. And
it goes back to what you were saying earlier is management awareness,
contingency planning, how well the people that are needed to implement
these plans are trained, or procedures they're using--it's all of those
quantitative issues that come into play. And I think we have to look at
how well the licensee has planned, understands everything that needs to
be done, what needs to be done if something goes wrong during the
DR. SEALE: Let me state their problem a little bit
differently. You're talking about, I would gather, the response once
the application has come to you. I think what they're referring to is
the problem of what information does the utility have on which to make
the decision as to whether or not you want to go the risk-informed way
or the traditional way. Are you, by virtue of the implied enhanced
preciseness of the risk assessment, presenting the licensee with a
situation where they're sort of lured into not going the PRA way because
it appears that the PRA way is the hard way?
MR. CORREIA: No, if I were inspecting this situation, I
think personally my comfort level would be higher if I did see PRA
numbers being utilized in conjunction--
DR. SEALE: Yes, but you're working -- or the primary number
you're concerned with is payroll when you make that -- the guy that
makes the decision is the manager, and he worries about whether or not
he's got an adequate PRA staff to pursue this thing. Essentially,
you're getting a route where he doesn't have to have a PRA staff and
saying it's probably going to be easier if you do it that way, or
suggesting it anyway.
MR. BOGER: This is Bruce Boger. I just want to make sure
we're capturing our bounding this area. I think through the maintenance
rule baseline inspections we discovered that all the plants we're using
some sort of a PRA-based instrument for at power maintenance rule
activities. Is that?
MR. CORREIA: That's true.
DR. WONG: That's true.
MR. BOGER: So what we're really talking about now is
shutdown operations. Is that understood? I mean, we're talking about
an error set of issues here.
DR. BONACA: Well, not really. I mean, before we leave the,
you know, on line maintenance of power, there are tools, but certainly
simple metrics where you have, you know, system on the left and system
on the axis -- in some cases may not be adequate if you pull out
multiple systems out of service. Okay, because you are changing the
configuration in a way that that very simple metric doesn't apply
anymore in the way to give you the right insight. And even at PRA, even
if you use a PRA monitor, you have to make sure it has the ability of
evaluating multiple components. It doesn't come automatically. I mean,
you have to make certain software changes to the program to assure that
you can evaluate risk significance on the basis of the new configuration
that you have.
So I'm saying that not all approaches being used right now
at the sites from what I understand provide you that kind of ability to
make predictional risk.
DR. POWERS: But the typical software in these purposes would
only allow you to do one at a time.
DR. BONACA: One at a time. One at a time, and you're right,
I mean, there are some clear examples how the risk achievement worth of
the component is very much dependent on the configuration they pull it
out from. I'll give you an example, which is so clear. A plant with
two (**inaudible**) generators. You're taking one out of service
typically the risk achievement worth is about a factor of six or seven
-- it's one of them. Now if from this configuration, you remove the
MR. BOGER: You can't do it. Tech specs wouldn't allow that.
DR. BONACA: I understand that. I'm only giving you an
example of, you know, for a very simple case where tech specs would
limit. If you remove the other one, its worth may be a factor of 40 to
60. The same component is worth now ten times because you're removing
it from a configuration which already you pulled out the other
component. Now, this is a very clear example. Nobody would do that.
But the same kind of, you know, upheaval in rankings will occur in
components less obvious and certainly not tied to tech specs. That's
why we consider this issue important insofar as how it was being
addressed, okay. And those numbers are very representative. I mean,
again, I gave you numbers for the original (**inaudible**) because they
MR. HOLAHAN: This is Gary Holahan. I think we have some
confusion on a point. The licensees who have either an on line risk
monitor or who precalculate, you know, maintenance configurations, you
know, calculate them with multiple pieces of equipment out of service.
It's not a matter of adding, you know, the importance measures together.
The calculations are actually done with the multiple pieces of equipment
out of service.
For licensees who use some sort of matrix or look-up table,
they are restricted to use those pre-analyzed configurations. And so if
they take three things out of service at the same time, and they don't
have a matrix that covers three at the same time, they can't use that
matrix, okay. So I, you know, I don't share your concern that there's
things going on that are not being analyzed.
DR. BONACA: Well, the way you explained it is different from
what I heard before.
MR. HOLAHAN: Well, we have with us a number of the people
who inspected all those plants I think--
DR. APOSTOLAKIS: This is a good example, though, of what I
was trying to talk about to the Commissioners this morning -- that the
sense that the guy has the PRA has more freedom to things. There is a
MR. HOLAHAN: Well, I think that's a different issue.
DR. APOSTOLAKIS: No, it's not a different issue, and this is
a good example of that.
Because you're saying that the guy who doesn't use the PRA,
has a matrix is restricted to that.
MR. HOLAHAN: Yes.
DR. APOSTOLAKIS: Well.
MR. HOLAHAN: Yes. So he has less freedom.
DR. APOSTOLAKIS: Except to have freedom to do more of those
seems to me to be a benefit.
MR. HOLAHAN: It is.
DR. APOSTOLAKIS: Yes, and that's what I'm saying.
MR. HOLAHAN: And that's why many licensees have done it.
DR. APOSTOLAKIS: Yes, but the thing that bothers me, though,
coming back to the same issue is when I go to Section 1.2, Risk
Significant Configurations. It's two paragraphs, one very long. So it
says, a risk significant configuration is one, and this is a standard
risk definition. Two, a configuration that would significantly affect
the performance of safety functions. That's all. Then the rest of the
discussion is on risk criteria--conditional core damage probability, and
so on. Where is the similar analogous discussion on a configurations
that would significantly affect the performance of safety functions
without quantifying risk? Where in the document can I find that and
say, yes, even those guys are doing something similar?
MR. CORREIA: Since we are pursing endorsement of the NEI
guidance document, that is--
MR. HOLAHAN: 11.3
MR. CORREIA: Addressed in 188.8.131.52, page 6.
DR. APOSTOLAKIS: Yes.
MR. HOLAHAN: And 10.7.
MR. CORREIA: And it takes basically the same approach as the
guidance for shutdown conditions. It's considering the impact on plant
safety functions and other considerations--redundancy, duration,
compensatory measures, contingencies, protective actions--all those
DR. APOSTOLAKIS: Is this really -- is attachment two?
MR. CORREIA: I think it's Section 11.2, NEI guidance
DR. WONG: Yes, I think it's attachment two.
MR. HOLAHAN: I don't have the letter.
DR. APOSTOLAKIS: And which section was this?
DR. WONG: 184.108.40.206.
DR. POWERS: It starts on page five.
DR. APOSTOLAKIS: 220.127.116.11 of the technical considerations.
So, now again, I think that it will be much easier for someone to
consider the degree of redundancy, appropriate compensatory measures,
contingencies and so on than to actually quantify these things. So I
don't see what incentive I would have to quantify anything. Isn't it
easier to say, yeah, I identified the key safety functions, and I
considered the degree of redundancy. What does that mean? It seems to
me that there is a imbalance between the two approaches. And then in
the main body, it says--
MR. BARTON: Do you mean back in the reg guide, George?
DR. APOSTOLAKIS: Back in the reg guide, page four. The
scope of the assessment may be limited to structure, systems, and
components that the risk-informed evaluation process has shown to be
significant to public health and safety. So my risk-informed evaluation
process can be qualitative.
MR. CORREIA: Not following the guidance that we have.
DR. APOSTOLAKIS: Not following--
MR. CORREIA: Because right now we've defined the -- one
method of determining what that scope would be is a high safety
significant SSCs that maintenance rule has already identified, which
includes consideration of risk insights, anything modeled in the PRA.
DR. APOSTOLAKIS: But the previous page, it says, these
assessments do not necessarily require that the quantitative assessment
of probabilistic risk be performed.
MR. CORREIA: That's true -- for the assessments.
DR. APOSTOLAKIS: But your answers says that it has already
MR. CORREIA: No, the scope versus the assessment. Two
different pieces of the rule. Scope may be limited using a
risk-informed evaluation process, versus what the assessment -- how the
assessment needs to be performed.
DR. APOSTOLAKIS: Well, it says here, assessing the current
plant configuration is intended to ensure that the plant maintenance
configurations do not have a significant effect on the performance of
key plant safety functions. These assessments do not necessarily
require a PRA.
MR. CORREIA: Correct.
DR. APOSTOLAKIS: But then the scope that the -- a
risk-informed evaluation process--
MR. CORREIA: If a licensee chooses to limit the scope, then
they have to use a risk-informed evaluation process. They don't have
to. That's an option.
DR. APOSTOLAKIS: All right.
MR. CORREIA: They can chose to include the whole scope of
the maintenance rule, and that's deterministically described in the rule
MR. HOLAHAN: So, George, with respect to your concern about
encouraging people to use PRAs, that last sentence in the maintenance
rule says you can reduce the scope of what's covered by the maintenance
rule probably by quite a lot, maybe by two-thirds, maybe by 75 percent.
But how do you do that? You do it with the PRA. It's the one and only
MR. BOGER: That's the scope of the equipment that you have
to consider in the--
MR. HOLAHAN: That's a pretty good encouragement.
DR. POWERS: A good point.
MR. HOLAHAN: And although I agree with your concern in
principle, I think in reality what will happen is the licensees will
have a PRA because they want to take advantage of that last sentence.
They'll have a PRA because they want to be in the position of addressing
risk significance of inspection findings. They have a number of reasons
why they want to have a PRA. Once you have it, once you have the
infrastructure, it's not so hard, you know, to use it for maintenance
rule, for risk-informed activities, for a lot of other things.
DR. APOSTOLAKIS: Right.
MR. HOLAHAN: So if you pick up one rule or one page of one
rule and say, you know, does this page itself encourage or discourage
having a PRA, I think you don't get the whole story.
DR. APOSTOLAKIS: And I don't intend to do that. But the
thing is I think the example -- what you pointed out just now is very
good. Somehow I missed that when I read this. You're confident that
all the utilities will not miss it; that the message is there. Or, with
practice, they will realize--
MR. HOLAHAN: I'm positive--
DR. UHRIG: When word gets around.
MR. HOLAHAN: I'm confident that the utilities will figure
out how to reduce the scope of the maintenance rule by recorders, yes.
DR. APOSTOLAKIS: By the way, I hope that everyone
MR. HOLAHAN: Just the assessment.
UNKNOWN SPEAKER: How much.
MR. HOLAHAN: Oh, the assessment part, sure.
DR. APOSTOLAKIS: The use of PRA should be encouraged. It's
not just, you know, to introduce a new technology. There is much more
information there than in a traditional analysis.
MR. CORREIA: And we've seen that through implementation of
the other parts of the maintenance rule, where risk insights were used
for risk ranking determinations, monitoring situations. It was a very
useful tool, with useful insights, that helped utilities and our
inspectors do just that.
DR. APOSTOLAKIS: Anyway, I promise you that you will get the
same comments every time I see a document that has a sentence PRA is
only a two--
MR. HOLAHAN: Yes, sir.
DR. APOSTOLAKIS: I'm sick and tired of PRAs only a two--
DR. WALLIS: George, it's not having more information. With
a PRA, there is a direct link between these evaluation of components and
strategies and managing and so on and public safety. There's actually
the connection made, and with the deterministic regulations, you cannot
see the clear link between what's specified and the effects on public
DR. POWERS: Well, Graham, I get -- I think that it cuts both
ways. And one of the things that I think we have to worry about, not in
the context so much of this rule, but in a broader context sometimes is
that we have plants that were designed, developed, in a subsystem by
subsystem by plant basis. We can now analyze them as a coherent whole.
And when you do that, you identify subsets of things that did not need
to be covered by the maintenance rule. Just as Mr. Holahan pointed out,
the PRA can reduce the scope. But when somebody looks from the outside
and says, gee, the NRC's not holding the licensees' feet to the fire on
these things, on many of these systems now, because of some argument by
risk. And that sounds bad to me. And I'm wondering how we convince
people that, in fact, by going to the PRA framework, we're actually
improving the safety and not cutting back.
DR. WALLIS: It's the word safety instead of risk.
DR. POWERS: I think that -- well, I think there's some
mileage there, but I think it's -- it is, indeed, showing then that with
the PRA, there, indeed, is so much more information than there is with
the traditional approach. And we understand the system better.
DR. WALLIS: It's a measure of safety. It's a measure of
public safety. The word risk is being used all the time. Really, it's
a measure of safety. It's telling the public how safe the plants are.
It's a safety probabilistic analysis.
DR. POWERS: You're running into the language that leads the
industry to call it a PSA instead of a PRA.
DR. APOSTOLAKIS: Are we discussing this document as whole?
I think we are. We have destroyed your presentation.
MR. CORREIA: Not a problem.
DR. APOSTOLAKIS: For the life of me, I don't understand the
definition of the unavailability. The proposed definition -- equipment
of out service is considered unavailable. Now, just tell me what
dictionary would accept that as a definition? I can't -- is there a tax
imposed on people when they use the probability? Is there something
that causes -- inflicts pain? I don't understand this. To say a
definition is when equipment are out of service, and then go on to say
support system unavailability may count -- may be counted against either
the support system or the front-line systems. All these under
definition. I -- it's very simple. It's a function of tying the things
up. Why is it so difficult for people to understand that?
I -- it's beyond me. And then credit for a dedicated local
operator can be taken. That's part of the definition. Now, you might
say this is not the right title for this subsection, but is it so
difficult to give a definition, to start with a definition and say the
fraction of time the thing is up is called the availability. And you
calculate it by taking the ratio that you have here. And now, what are
the things that affect that thing, and list everything else.
And now, you know, and then maybe in five years instead of
fraction of time, we'll say the probability. It's beyond me why we have
to distort -- and then in the main text, it says, availability is the
time the SSC is capable of performing its intended function, expressed
as a fraction. It's the time expressed as a fraction.
DR. KRESS: A fraction of something.
DR. APOSTOLAKIS: It's a fraction of -- it's actually the
DR. WALLIS: It's not using decimals.
DR. POWERS: George, this has a unit problem here.
DR. APOSTOLAKIS: I'm having a big problem here. What's
wrong with saying the availability is a fraction of time that the SSC's
functional, capable of performing it intended function?
Is there problem with that?
MR. SCOTT: Yes.
DR. APOSTOLAKIS: Yes, what is that?
MR. SINGH: Wayne?
MR. SCOTT: I'm Wayne Scott with NRR. I can only say that
it's a function -- it's a practical measure. In the power plants, they
don't go out with a little fraction measuring device. They go out with
a watch, a stop watch, a clock. And they measure hours. That's the
DR. APOSTOLAKIS: No, that's not an issue.
MR. SCOTT: Well.
DR. APOSTOLAKIS: That's how you measure it. But that
doesn't define it. The definition is the fraction.
DR. WALLIS: You divide one set of hours by another set of
hours, and you get something to (**inaudible**).
DR. APOSTOLAKIS: What?
DR. WALLIS: Yes, you--
DR. APOSTOLAKIS: What is the availability of this piece of
equipment? The definition is you go out with a stopwatch and measure
this and you divide by that, is that the definition? The definition is
that if I consider a long period of time, the fraction of time that--
DR. WALLIS: That's in the denominator.
DR. APOSTOLAKIS: These are the details of how you calculate
DR. WALLIS: Well, I think George is right. It's obvious.
Let's fix it.
DR. CORREIA: And we will fix that, and we'll advise NEI to
fix it also.
DR. APOSTOLAKIS: I mean, the fraction that is here is
correct. But that's the definition actually. That's the definition: up
time divided by total time.
DR. POWERS: Please continue.
MR. CORREIA: Thank you. We have been -- since our last
meeting, we have been looking at NEI's Section 11 guidance document for
this rule change as well as working on our own draft guide, which you
have -- which you see is an early October version that you have before
you. Again, our objectives for this regulatory guide was to endorse
acceptable industry practices. We weren't out to create something new.
We looked at every plant in the country, and I think what we're trying
to capture here are what we believe are the better existing practices,
with this should to shall requirement. Then since the Commission has
given or will be giving industry a option to reduce scope, the guidance
needed to have a methodology to define that scope. We believe it's
there. Again, I believe it all can be accomplished using existing
information and tools that the utilities have.
One of the items that the Commission directed the staff to
do was to interact with stakeholders. We have spent all of the summer
and some of this season interacting with NEI and utilities and the
public on the NEI-proposed guidance. We've had four public meetings
with NEI on these issues. NEI also sponsored a -- what I consider -- a
well attended workshop, though hurricane shortened, workshop in Miami.
Got a lot of good feedback from utilities at the workshop on what our
proposals were, what NEI was proposing, and we did take those into
consideration as we continued on in the process. And we have looked at,
to date, five revisions of the NEI guidance. So we were -- we are
working very closely with NEI--lots of discussions, lots of give and
take on what is a reasonable way to develop guidance to implement this
DR. POWERS: You've been careful -- at general times in your
language to say that you've interacted with stakeholders.
MR. CORREIA: Yes.
DR. POWERS: And not just NEI by itself. Did you have
significant interactions with people who would usually be categorized as
MR. CORREIA: No, not really.
DR. POWERS: In other words, this issue could be just a
little more -- a little too arcane for that forum, though Hub Miller has
told me up in Region I he has an extremely sophisticated public up
there. So they may be able to approach this. What was the situation?
MR. CORREIA: Not really. No.
DR. POWERS: Okay.
MR. CORREIA: Not anyone outside the nuclear industry
DR. POWERS: There didn't seem to be -- he said -- I mean, it
is a little arcane. I mean, it's a detail that may elude
MR. CORREIA: I believe that's the case. And I think
considering that this I don't want to say requirement, but this
recommendation has already -- has been on the books for many years now,
and industry is implementing it. And, in effect, this is a should to
shall change, and it's being implemented we believe correctly in most
cases. So I don't think it's a highly controversial issue.
DR. POWERS: Well, I think, in fact, the licensees were the
ones that pointed out that it said should instead of shall or vice
versa. I believe they are the ones that first brought it to everybody's
MR. CORREIA: We recognize that this was a problem during the
early stages of the baseline program. And I think at that time,
industry endorsed the change, to change should to shall, yes.
Where we are today. And regarding the NEI guidance
document, we believe it's very close to meeting all of our needs to the
point where we believe that there are no major issues remaining; that
there are some minor issues or items that we still need to dialogue with
NEI on reviewing their latest version. And I'll let Dr. See-Meng Wong
speak to these issues right now.
DR. WONG: Thank you. As Rich has stated, we have gone
through five revisions of the NEI document, guidance for the
implementation of the A4 assessments.
DR. APOSTOLAKIS: A revision?
DR. WONG: What?
DR. APOSTOLAKIS: What is a revision? A new revision is a
minimal change to the current document or is a negligible change?
DR. POWERS: Well, I think a revision is what the authors
tend to call it revision.
MR. CORREIA: Right.
DR. WONG: Yes. We had a lot of discussion in the concepts
and the language of what we think addresses our concerns, so, in
general, we think the NEI documentation, document is in consonance with
the concepts that we've tried to articulate in our draft reg guides.
Now the three remaining issues is this is the latest version that we
have and until yesterday, we were looking at what the NEI has developed.
And the three issues that we think that NEI needs to provide further
clarification in their document is in the area of managing cumulative
risk. While the document addresses that plants that have on line
maintenance in which several SSCs are out of service should address
cumulative risk and the cumulative risk impacts should be reflected in
the baseline PSA, one of the statements and this is the latest
statements in which they said that the threshold should be following the
permanent risk change guidelines of the EPRI PSA guidelines. Here we
are in somewhat disagreement because the Section 4.2.1 of the EPRI PSA
guidelines that addresses permanent risk changes are based on a relative
change, a percentage change. And what we would prefer is that the
guidelines that we -- that licensees should be using should be the reg
guide 1.174, Risk Acceptance Guidelines.
DR. APOSTOLAKIS: I'm a bit confuse now. Doesn't 1.174 deal
with permanent changes?
DR. WONG: Yes.
DR. APOSTOLAKIS: And you are now talking about on line
maintenance. Is that the permanent change?
DR. CORREIA: In some cases, yes.
DR. WONG: In some -- we're talking about--
DR. APOSTOLAKIS: Temporary? No?
MR. HOLAHAN: No, typically it would be a temporary change.
No, what we're talking about is the case in which a licensee has put
into practice, okay, a long-term plan for taking equipment out of
service. You don't need to deal with those as temporary conditions,
since it's -- you know -- since it's a long-term plan, you can
pre-calculate that in the baseline program.
DR. POWERS: And, in fact, you do. I mean ordinarily you
MR. HOLAHAN: Yes.
DR. POWERS: Because you would have the availabilities would
be affected by your--
MR. HOLAHAN: Well, no, no, I think it's more subtle than
that. The unavailabilities are not treated in a random fashion. The
licensee has a program in which they pre-plan what to take out, in what
sequence, what combinations -- you can pre-calculate that.
DR. APOSTOLAKIS: Sure. But I thought in another one of the
guides, not 1.174, I don't remember which one, there were some
additional criteria similar to what you have here for temporary.
DR. POWERS: Yes, in 1.178, they have the allowed outage
DR. APOSTOLAKIS: Right. So that's the one that applies
here, is it not? Not the 1.174.
MR. HOLAHAN: 1.17 -- in regulation 1.177, the technical
DR. APOSTOLAKIS: Yes, that's the one should apply here for
temporary changes, even though they are periodic or both.
MR. HOLAHAN: It could. You -- I think you could do that.
What we did in 1.177 is, in effect, to recognize that because it had to
do with technical specifications, it was not a one-time thing. It was
something that would be repeated. And you had at least a general idea
of how often it would be repeated. And so rather than have a cumulative
effect what we did is, in fact, we reduced the allowable risk from each
individual one to recognize that it would be used multiple times in one
year. That's why it's down to five times ten to the minus seven, which
is, in effect, a smaller number than we would ordinarily consider.
MR. BARTON: And we agreed with the staff on that, and said
you should not use that for on line maintenance.
DR. APOSTOLAKIS: You should not.
MR. BARTON: (**inaudible**) our letters. That's right.
DR. POWERS: Yes, we agreed because of the terribly rational
way they came about the -- coming up with that five times ten to the
DR. APOSTOLAKIS: Well, it's three hours.
DR. POWERS: Yes, it had to do with historical outages and
comparing them -- they weren't allowed -- that would get approved and
what -- translating those back into a risk space--what kind of risk were
they allowing those -- it was really elegantly done. That's why.
DR. KRESS: I do recall that it was.
DR. APOSTOLAKIS: Well, the whole point, I don't know, if you
use 1.174 and you average out over the whole year those short periods of
time, then unless they're not short anymore, on line maintenance then
won't the effect disappear in the averaging process, in that you have to
go to 1.177. The averaging is a tremendously leveling process. But
that's an interesting point. I had not thought about that. At which
point do you decide that some change is permanent?
MR. HOLAHAN: The effective PSA application guide from as
early as -- at least until 1995 -- but I think probably in the earlier
drafts as well recognizes this and has a section on the subject. I
believe it's the section right after they talk about guidelines for
temporary changes. They suggest that it shouldn't be used for the kind
of activities that are done on a repetitive nature.
DR. POWERS: And that, indeed, is the advice we got from this
Committee as well, I think. That's what that says.
DR. KRESS: George, does that have a implicit assumption that
the risk of random effects is linear with time, the longer the time you
DR. APOSTOLAKIS: The way we're doing the calculations now,
DR. KRESS: And that's not right, is it?
DR. APOSTOLAKIS? Huh?
DR. KRESS: And that's not right, is it?
DR. APOSTOLAKIS: It's not for the temporary changes probably
DR. KRESS: I think there's something wrong with this
DR. APOSTOLAKIS: But I think the fundamental thing is that
if you do something only for a fraction of the time, but you do it
periodically, okay, every whatever months, and you want to look at the
total CDF for the year, then, of course, there -- the fraction of time
that it's there is important, right?
DR. KRESS: Yes.
DR. APOSTOLAKIS: So that tends to reduce the impact that
such a spike might have on the average.
DR. KRESS: Yes, but when you put it into the CDF, say--
DR. APOSTOLAKIS: Yes.
DR. KRESS: It's only a linear average?
DR. APOSTOLAKIS: Everything is linear here. It's a linear
DR. KRESS: And I'm asking you if that's the correct way to
average those kind of things in, because the risk of -- is actually
that's an issue at the time.
DR. APOSTOLAKIS: During those temporary situations, I think
you can make a good case arguing--
DR. KRESS: The time is shorter--
DR. APOSTOLAKIS: That it's non-linear in time. It's
non-linear in time. But we don't do that. We just take the duration.
DR. KRESS: Is it something worth worrying about or is it?
DR. APOSTOLAKIS: In the old scheme of things probably not at
MR. HOLAHAN: In the past, maybe we should have worried about
it, but now we have the maintenance rule, and its assessment of the
configuration risk to deal with that issue. It will prevent licensees
from, you know, from, in effect, taking that maintenance activity and
doing it at some random time.
DR. APOSTOLAKIS: Well, that's not what Dr. Kress is talking
about. I think you are talking about during that short time, the
several hours, say, when I'm doing something, isn't the risk actually a
non-linear function of time?
DR. KRESS: Yes, that's exactly what I had.
DR. APOSTOLAKIS: And I believe it is.
MR. SIEBER: Sure.
DR. APOSTOLAKIS: There's human errors, for example, probably
are -- but we are not calculating on that. And it's probably a second
DR. KRESS: Yes, that's what I was asking.
DR. APOSTOLAKIS: Probably a second order effect.
DR. KRESS: Is it a significant effect we have?
DR. APOSTOLAKIS: So the averaging process is already --
because after all, you know, a lot of the stuff we're doing is averaging
time -- the unavailability that we use -- excuse me, the time expressed
as a fraction that we use is actually an average over time. So in some
instances is higher than what we use.
DR. POWERS: We need to progress.
DR. WONG: Yes, this is one example. And another example
that I'd like to bring to the table for discussion is are -- in the NEI
document, there is a statement on configuration-specific CDF of -- in
excess of 10 e (**check word**) minus three that if the licensee
voluntarily enters into this configuration, they should be very careful.
They should -- go into very short time. Here, our issue here is that
this is interim guidance, and there is pending development of the safety
goal assessments, and we--
DR. POWERS: What the licensee is doing is he's risk capping.
DR. APOSTOLAKIS: Right.
DR. GONG: Yes.
DR. POWERS: And you're telling him that you're going to come
up with a better risk cap for him?
MR. HOLAHAN: No, what we're telling him is the issue of risk
capping, which we've discussed with the Committee on a number of
occasions is an open issue.
DR. POWERS: That's right. And he's voluntarily doing a risk
MR. HOLAHAN: Right.
DR. POWERS: Because he's a smart guy.
MR. HOLAHAN: He's a smart guy. Yes, well, of course, we may
all agree later that it could have been capped at some better point, or
maybe the cap isn't needed at all. But for now, we just want to -- we
don't want to use this as the mechanism for deciding definitively an
issue that I think is before this Committee and the Commission on a --
in other venues.
DR. POWERS: I think I understand what you're saying, but I
surely admire the fact that he's risk capped.
MR. HOLAHAN: Which has been in the PSA application guides
DR. WALLIS: Can I ask you something now? Now, when you've
done all this, what has been achieved? Can you put this on some scale
of achievement, like you have now reduced the risk to the public during
maintenance by some amount by doing this?
MR. CORREIA: I don't know if we can say we can reduce it;
certainly, manage it at reasonable or relatively low levels. You hope
that maintenance is achieving or maintaining equipment reliability at
the minimum expense of unavailability.
DR. POWERS: I think that the NRC staff can pat itself on the
back and take a great deal of credit for being responsive in an evolving
environment. We have machines whose design was based on doing the
maintenance largely during shutdown. People doing that have found that
there are advantages, both economic and from a risk perspective, to
doing some of that maintenance during normal operation. And the staff
has found a way to examine this and to construct their regulations so
that it's permissible for the licensees to do this.
DR. WALLIS: I think it would be very nice if they could have
put it on a scale that's understandable to the average person, which
says that we have saved the industry X dollars, and at the same time we
have increased public safety by Y, on some scale. Because it sounds
good, but is it important or not? I mean, I don't know.
DR. KRESS: Would that you require to calculate the risk with
and without this rule being present in its present form?
DR. WALLIS: Yes.
DR. KRESS: I don't think -- I don't really think you can do
DR. WALLIS: I think you should do that for every time you
write some new rule or make some legislation or make some new hoops for
people to jump through or remove some old hoops, you should put it on a
scale of meaningfulness to public safety and cost.
DR. APOSTOLAKIS: I am convinced even without the
quantitative estimate that this is a good thing.
DR. POWERS: Well, I think it's there already. I think if
you look at the statements of consideration--
DR. APOSTOLAKIS: Yes, it's a good thing.
DR. POWER: That what you're asking for is right there in the
MR. HOLAHAN: Yes.
DR. WALLIS: Is it a minimally good thing or is it
significant? I don't know.
MR. BARTON: Greater than minimal.
DR. APOSTOLAKIS: If you quantified it, it is 10 percent
MR. SIEBER: Greater than negligible.
DR. POWERS: Well, I think -- no, I think this is
MR. CORREIA: It has a net safety benefit compared to the
DR. UHRIG: Well, it's also the backbone of the management of
aging. On the basis that is -- the records associated with the
maintenance rule are important in the considerations of what has to be
done in license renewal.
MR. CORREIA: Yes, and the Commission has given licensees a
lot of credit in license renewal space for what they do under the
maintenance rule. Sure. That's very true.
DR. APOSTOLAKIS: There is something about this I don't like,
though. I mean, I know it's minor. I don't like seeing things like
regulatory guide 1.174 versus PSA applications guide. I really don't
like seeing that because 1.174 may we put in the word for this new issue
the approach of this versus the approach of that--something like that.
Because when I saw this, I said, gee, you know, all of a sudden the PSA
applications guide is challenging 1.174. That's not what you meant?
DR. WONG: No, no, that not what we meant.
DR. APOSTOLAKIS: I know you didn't mean that.
DR. POWERS: I think you're overly sensitive.
DR. APOSTOLAKIS: Today, I'm so sensitive. I'm completely
DR. WONG: Okay, the--
MR. HOLAHAN: But, but--
DR. WONG: Go ahead.
MR. HOLAHAN: Just to challenge your sensitivity a bit.
These two documents are not entirely separable at this point, okay,
because, in fact, what's happening is the NEI guidance is referencing
the PSA applications guide, and we're being asked in the staff's
guidance document to endorse that, okay. So it would bring at least
that piece of the PSA applications guide into a regulatory guidance
DR. APOSTOLAKIS: Yes, but it's not versus 1.174. I mean,
it's not opposing 1.174.
MR. HOLAHAN: Well, it is -- with respect to the--
DR. APOSTOLAKIS: Okay, it's not worth pursuing.
DR. POWERS: That's true now that you've raised it.
DR. WONG: Okay, the final item that we think is a minor
issue -- this is on -- I think on page eight of the final draft of the
NEI document. There is a statement that is described here. It says the
shutdown assessment need not be performed for SSCs whose operability is
not required by technical specifications during shutdown mode. And the
words here operability, we would prefer that functionality is not
required and scratch out or delete the term tech specs because the tech
specs branch does not agree to that.
MR. HOLAHAN: Well, I think the issue is I think we all know
that safety during shutdown is not really being controlled by technical
specifications, but by--
MR. BARTON: That's right.
MR. HOLAHAN: Configuration controls, you know, being done by
other industry programs.
DR. SEALE: Read what it is want to say again.
DR. WONG: Of what we want to say?
DR. SEALE: Yes.
DR. WONG: What we want to say is that the shutdown
assessment need not be performed for SSCs whose functionality is not
required during shutdown mode. So it takes away the questions of
whether it's tech spec or not. Okay?
DR. SEALE: Okay.
MR. HOLAHAN: Well, it says required. The idea is that the
equipment is necessary for the functions that are important for
shutdown. So it's a -- we don't want to tie it to regulatory
requirements since we don't think those do very well for shutdowns. We
want to try it too, you know, functional requirements.
DR. POWERS: And I agree with you -- it should be a very
minor requirement, and you are to be congratulated for being scrupulous
in your examination.
MR. HOLAHAN: Okay.
DR. WONG: Okay.
MR. CORREIA: Thank you. Given that and those we believe are
the three issues that we still are dialoguing with NEI on, our plans are
to finalize our draft guide endorsing what we hope will be a
soon-to-be-again revised NEI guidance document that incorporates these
changes and to issue the draft guide for public comment, because we
still have not got to that point yet.
DR. KRESS: How will you deal with the ten to the minus
three? Would you like for them to just remove it or would you?
MR. CORREIA: No, acknowledge the fact that this is still
under Commission review, and it may change in the future.
DR. KRESS: It's just an acknowledgment in the endorsement?
MR. CORREIA: Yes. We have still quite a lot to do. As you
can see, this is our schedule to the point where the reg guide and the
rule would become final. We're meeting with the Commission next week on
this very subject. They want to see the draft guide soon. We've
committed to get that to them by the end of this month, and have by the
middle of next month the draft guide that's out for a 30-day public
comment period. And early next year, we'll be back here again to tell
you what the final guide looks like. So this is an important step, but
we -- I believe that we're sufficiently close enough for the NEI
guidance document that we would like to move forward and continue the
process and have the -- let the public take a look at it and get their
feedback. And hopefully, next spring the Commission will have it for
them to decide on whether or not it's acceptable.
DR. WALLIS: Do you seriously expect any public comment
except from the utilities?
DR. APOSTOLAKIS: No.
MR. CORREIA: There are a few organizations that always
comment on our reg guides. We expect that. I would think since we're
endorsing or attempting to endorse an industry guidance document, we
wouldn't receive many comments other than specific, maybe word changes,
or things like that, but certainly not many negative comments, no -- I
don't believe. Yes.
MR. SIEBER: Since you still have a couple of minor
outstanding items, do you expect a letter from the ACRS at this point in
MR. CORREIA: If, well -- I think we need something.
Certainly, if we can get these minor changes resolved, if we can't, we
would address them in our reg guide as clarifications--
MR. SIEBER: Right. Exceptions, clarifications, or whatever.
MR. CORREIA: Exceptions, yes.
MR. SIEBER: Sure.
MR. CORREIA: So one way or the other, either NEI puts them
in their guidance document to our satisfaction or we put them in our
MR. SIEBER: Okay.
DR. APOSTOLAKIS: So are you asking for a letter?
MR. CORREIA: Yes.
DR. APOSTOLAKIS: This time?
MR. CORREIA: Yes.
DR. APOSTOLAKIS: Just to say whether you should go out for
MR. CORREIA: Yes. That's our goal at this time.
MR. BARTON: But whether I guess they are far enough along
and the issues remaining are minor enough that they can proceed. I
guess that's what they're looking for. If we can come to that
conclusion, that's what they're looking for.
DR. POWERS: Well, I think we -- I mean they're going up to
talk to the Commissioners to ask them to come here and talk to us. I
think we just owe them a response, and it should be an easy one for us.
MR. CORREIA: Any other comments?
DR. APOSTOLAKIS: Now, the -- I guess a different font
indicates this is NEI attachment two?
MR. CORREIA: Yes.
DR. APOSTOLAKIS: It talks about incremental core damage
probability, okay, not as a time expressed as a fraction. So it doesn't
hurt to use the word probability.
MR. BARTON: What page you on, George?
DR. APOSTOLAKIS: Fourteen. I would really like to see
appendix B be burned in public.
MR. SINGH: He's coming back, George. NEI is here.
DR. APOSTOLAKIS: It doesn't matter. The other thing is just
as a side comment, the ACRS wrote a letter last month listing a series
of problems with importance measures. I think the ICDP and the ILR take
care of a lot of those concerns. It's a step forward, because the
relative measures, you subtract and so on. There are still some issues
that are valid, but I think some of the gross -- by the way, not gross
-- I've been chastised for that word -- the big problems -- some of the
big problems go away when you go to these--
DR. SHACK: Crudeness was your other one.
DR. APOSTOLAKIS: Crudeness, yes, that was what the committee
finally came up with. Okay, so that's just a comment, though there are
ways around those problems.
MR. BARTON: Any other questions of the staff at this time?
Thank you, Rich. If not we'll hear from industry next.
MR. CORREIA: Thank you.
DR. WONG: Thank you.
DR. POWERS: Bonjour, Tony.
MR. PETRANGELO: Good afternoon. My name is Tony Petrangelo.
I'm from NEI. This is Biff Bradley from NEI. Our purpose today is
really to tie a big bow around what that staff just told you, and maybe
give you a little bit more background and perspective on how we got to
First of all, let me talk a little bit about the industry
guidance. We've been working on that for quite some time, really since
last summer before even the rule came out for public comment. Biff
chairs our maintenance rule provision task force. That's been in place
for a couple of years. They took the first crack at revising the
guidance. They also helped us draft the industry comments on the
proposed rule. We did send drafts of the guidance out for industry
comment as well as to the NRC staff, before we sent the draft in
September to the staff. We also conducted a workshop in Miami in
September. Got a lot of good feedback there on the guidance that led to
the latest interactions with the staff.
Let me go back to the rule -- that's how we got the guidance
to the point where it's at. I mean, we don't just sit downtown and make
this up as we go along. We get a lot of--
MR. BARTON: Thank you for clarifying that.
MR. PETRANGELO: We got a lot of input from our members. We
can't do our job without them, and we take their comments very seriously
and try to address them all. So what you see reflects a great deal of
With regard to the--
DR. POWERS: But when we send it out for public comments, we
wouldn't expect any of your members to comment on it--
MR. PETRANGELO: You may get some very short comment letters
saying go for it.
DR. POWERS: We love it, and things like that, sure. Okay.
MR. PETRANGELO: Because it's been around once. And that's
the way we wanted it, quite frankly. We didn't want the public comment
period, at least from the industry perspective to be, give the staff a
lot of work to do.
Our objective has been to get a regulatory guide that
endorses our guidance without exception, and it still is our objective.
And I think we're very, very close to that now.
Just background wise, with regard to the revised rule in A4.
If you take it at its highest level, you know, this started as a should
to shall exercise, the old rule, what was then A3, said licensees should
conduct this assessment when they remove equipment from service, okay.
Once the rule became effective, then there was a concern about
enforceability of that provision of the rule, because it was a should
with an exhortation and not a requirement. The industry has never
opposed to changing that to shall. We've always treated it as a
requirement because it's in the rule. The staff inspected to it in the
field, even though they couldn't issue violations because of that
concern, they did confirm that everybody is, in fact, complying with
that portion of the rule. Now, did they find some weaknesses associated
with that? Yes, they did. So this -- in the future, if somebody
decided not to do this anymore, now they will have the provision to
But it wasn't just as simple as should to shall. It never
is. And the Commission I think also was trying to address a concern
about well, once a licensee does the assessment, there's no requirement
for them to do anything with the results of the assessment. That's
where this second provision of the rule came in.
So at its highest level, the rule now requires you to do the
assessment, and also requires you to use the results of the assessment.
It is still a performance-based rule. It is not prescriptive about what
tools you use to do the assessment, okay. But it simply requires you to
do one. And just to get to George's point, because I think it was a
very good one about the use of PSA in the regulatory process.
Our position has always been that the Commission should be
encouraging the use of PSA and the regulatory process. That's what that
entire PSA policy statement is about, is encouraging that use and using
that tool -- yes, it is a tool -- I didn't want to bring it up, George,
but it is a tool. It is a means to an end, not an end in itself. And
as a regulatory agency, because of its -- the -- what it brings to the
table in terms of insights, they should be encouraging licensees to use
DR. APOSTOLAKIS: But, Tony, my objection -- I think that the
industry is reacting to perhaps the fear or responding to the fear that
they will be forced to have PRAs soon, so you guys don't miss an
opportunity to put it down; that -- in this -- and maybe it's
unintentional, but I read documents from NEI, and I know that within the
first two or three pages, I will see (**inaudible**) statements that I
can do this without the PRA, and don't forget PRA is only a tool. Well,
you know, it is a tool, but my goodness, it has so much information. It
looks at the thing in a different way. I agree that a lot of these
things we're doing now you should not be able to do only if you had the
PRA. I agree with that. But this constant putting down. I think if
you do a PRA, as Gary said earlier, your life should become easier.
You know, you go through this initial effort. You have to
educate your people, train them, spend the money, but then you can do a
lot of things in an easier way.
MR. PETRANGELO: Right.
DR. APOSTOLAKIS: And I bring up the example of 5059. If it
was up to me and you had a good PRA, anything that doesn't change the
CDF more than ten to minus six, go ahead and do it.
MR. PETRANGELO: Right. Yes.
DR. APOSTOLAKIS: See that's my--
MR. PETRANGELO: Yes, I understand where you're coming from
on that, but don't misunderstand why we say that, okay. We represent--
DR. APOSTOLAKIS: I understand that--
MR. PETRANGELO: All of industry.
DR. APOSTOLAKIS: We are so understanding, you and I.
MR. BRADLEY: Also, specific to A4, don't forget that
portions of the scope are outside the PSA, so you have to use some other
approach. For instance, if you don't have a shutdown PSA, you don't --
and also, you can confuse PSA with qualitative versus quantitative and
if you read in our guidance, we talk about using qualitative insights
out of the PSA, you know, and it's not a matter of using the PSA or not,
but how you use it. And, you know, you can get a lot qualitatively--
MR. PETRANGELO: Right.
DR. APOSTOLAKIS: I fully agree with you. I fully agree with
you. But I think, and these are legitimate reasons, but I think you
guys have gone too far the other way.
MR. PETRANGELO: But let me counter that by saying, we
lobbied very, very hard for this provision that got into A4 about a
risk-informed process for narrowing the scope of the assessment. The
staff wasn't going to do that. Okay, and in fact, you heard the last
discussion on that, just before that rule change was made. Okay, we
were vociferous about that, because we wanted something in the rule that
would encourage licensees to use their risk assessment. We've been
trying -- I mean this goes back a number of years, George, and you've
heard this in a number of your subcommittee meetings, trying to get a
return on the investment in that tool. And this is one that bridges --
we think -- bridges the gap between the deterministic and moving to
risk-informed Part 50. Even though the staff I think was going to do it
anyway in the guidance, we wanted it in the rule. We wanted it
explicit. And so I think Gary answered the question right. That is the
encouragement, by putting that provision in the rule with regard to the
scope of the A4 assessment.
DR. APOSTOLAKIS: Would it be inappropriate, Gary -- perhaps
even illegal -- to have somewhere in here -- I'm trying to address the
concern that Dr. Wallis and I have expressed many times. I find, as a
prelude, I find ourselves here too often having you and others say, but
the real intent is this, but this, but that. In other words, you have
to explain, interpret, what's in the written document. Why can't we
have a section some place that says, this is really what we're trying to
And also, if you have the PRA, these are the additional
things you can do. Is that inappropriate?
DR. POWERS: That's what the statement of considerations is.
DR. APOSTOLAKIS: But that's part here, is it?
DR. POWERS: Well, I mean, how many places do I have to write
these things, to say -- to write the ode to PRA in every thing that I
write? I mean, I'm going to put it on the letter.
DR. APOSTOLAKIS: Explain to me, please, what the role of the
statement of considerations is--
MR. PETRANGELO: It's to provide context for what went into
DR. APOSTOLAKIS: After this becomes part of the regulations?
MR. PETRANGELO: No, the reg guides -- should put this back
in context. The reg guide is a way to meet--
DR. APOSTOLAKIS: Of the rule? Yes.
MR. PETRANGELO: The rule. That's all. That's all the reg
DR. APOSTOLAKIS: So the statement of considerations, if I go
there now, will tell me what the advantages of using the PRA are?
MR. PETRANGELO: No. It will explain what the intent of the
DR. APOSTOLAKIS: Intent I agree.
MR. PETRANGELO: Right. You need to go back to the PSA
policy statement that the staff worked so hard on, and that you
reviewed. I mean, that's where you're going to find the stuff you're
looking for, I think.
DR. APOSTOLAKIS: No, that's not quite right. In this
specific rule, what advantage do I get by doing it? But anyway -- I
guess that's a minority view.
DR. SHACK: A vociferous minority view--
DR. POWERS: I mean, I think -- I think you protesteth too
much on this. I think you may be protesting too much--
MR. PETRANGELO: But I understand the point--
DR. POWERS: Beginning to suspect --
MR. PETRANGELO: And don't disagree with, Paul.
DR. POWERS: (**inaudible**) as useful as we thought.
DR. APOSTOLAKIS: I was reading again last night the other
NEI document, and when I saw, you know, PRAs only at two, I asked the
pilot to stop. I want to get out.
Enough said. Thank you.
DR. POWERS: They paid no more attention to you than we do,
MR. PETRANGELO: Let me move on.
DR. POWERS: Thank you.
MR. PETRANGELO: We talked about the rule making, and our
commenting on it, and why we felt so strongly about that provision of
the rule. And we were pleased with the way the rule came out.
The next job, of course, was getting guidance that the staff
could endorse. And, again, our objective has always been to get them to
endorse our guidance without exception. The main issue, okay, that came
up, and it came up with this Committee I think when the rule was
finalized, was the issue of the scope of the assessment.
MR. BARTON: Right.
MR. PETRANGELO: This -- ACRS was very concerned about the
scope and how licensees would take into account the configuration risk
assessment, and what you looked at.
MR. BARTON: Right.
MR. PETRANGELO: The -- and what we proposed to the staff is
to use the Level 1 PSA as well as the -- what we term in the guidance
document -- the high safety significant SSCs that were identified by the
expert panel. Most of those HSSCs overlap what was already considered
in the scope of the Level 1 PSA. But the expert panel could also add
SSCs that weren't in the Level 1 PSA, and pick up Level 2
considerations, pick up external events, pick up some other things.
We think that's a very, very good comprehensive,
conservative scope for that assessment. And that just applies to A4.
It does not apply -- the whole scope of the rule has not changed.
Hopefully, risk-informing Part 50 will change that to something very,
very similar, if not identical, to what we came up with this.
The relative ranking, all that stuff doesn't matter, in the
A4 scope, okay. That was done to address with the big maintenance rule
scope at which level you were going to monitor the SSCs at--at the plant
level, at the train level, and so forth. Okay. When we're looking at
the scope of the A4 assessment, those rankings don't matter any more,
because everything's already in the scope. So we think it's a very,
very conservative scope; that it takes into account the combination
question that the committee raised, and we're very comfortable with it.
And it's identical to what was approved or identified as an acceptable
method within the configuration risk management program that reg guide
1.177 identified. So there's some consistency with what was done in the
past. So we're quite please with that part, also.
The question going forward, and I think this is on the mind
of all licensees, and it -- we're still carrying a little bit of baggage
from the maintenance rule baseline inspections is what happens when you
take this out to the field? I mean, we had endorsed guidance before,
and we got into all sorts of questions on scope with the maintenance
rule, and other questions about the criteria that were established. And
there were three or four very thorny issues that came up during the
inspection process. So our objective not only is to get the guidance
endorsed without exception, but longer term is to get stable and
predictable implementation of the rule. And there's a lot at stake. If
this goes the way the first round went with the maintenance rule, no
one's going to want to do risk-informing Part 50. Okay.
So the proof's in the pudding here. That was another reason
why we lobbied so hard to get that provision in the rule, because we see
it as a step towards that end. And if we can't do it in the maintenance
rule, and get focused and get efficient, then the prospects for
risk-informing Part 50 are bleak.
So there was a lot of very important considerations that
went into the rule.
With regard to the minor exceptions that the staff went
through, those are trivial. Those -- they didn't even warrant putting
up on the screen. They are trivial. That's just some minor editorial
word smithing. There's no substantive issue associated with any of
those, and I'm not going to even get into those.
So that's the extent of the bow, unless you want to add --
it's been a long, arduous effort. It's not over yet. We still have to
go through the public comment period, which should be rather
straightforward. And we still have to go through the implementation.
And there's always bumps in that road.
DR. POWERS: Yes, I guess it's the expression--
MR. PETRANGELO: We'll have another workshop with the staff
hopefully to get between the lines understanding of the guidance, but we
seek this very, very positively.
DR. POWERS: Your prognostication on this -- where the rubber
meets the road -- after 120 days after this gets approved, have you
given any thought to where the difficulties are going to come?
MR. PETRANGELO: Yes, I mean, even though we don't have a
shutdown rule, and the shutdown piece of this really relies heavily on
the industry initiative we took eight years ago on shutdown risk
DR. POWERS: Right.
MR. PETRANGELO: And our NU -- what was -- the document was
NUMARC 9106. We don't have the same kind of quantitative thresholds for
shutdown that we have in the on line portion. That's more of a defense
in depth qualitative argument, okay. Now, it's a -- so, therefore, it's
a little bit more subjective.
DR. POWERS: Well, that -- I mean, but you're right. There
is something that has gained a lot of currency within the licensees. I
mean, they've done it enough that they -- they know how better than I
know how to interpret three oranges and all greens versus one red and
MR. PETRANGELO: Right.
DR. POWERS: They do understand that.
MR. PETRANGELO: I think what leaves me optimistic about that
part is that when the staff went out and looked for the baselines, and
they -- even though the rule didn't explicitly say shutdown, they looked
DR. POWERS: Sure.
MR. PETRANGELO: Okay, everybody was doing it. In fact, it
was a strength at most places, and my understanding of the feedback is
the way licensees planned and controlled outages, the staff wanted to
see more of that rigor for the on line plants. So it kind of turned
that whole argument around. And I think it speaks to how effective the
initiative has been.
So that's my biggest concern then this may be a no, never
DR. POWERS: So what you're saying is you're pretty confident
this is all going to be workable.
MR. BRADLEY: As confident as I think we can be. The only
other issue I'd mention is there are a lot of different flavors of risk
management, and, you know, how are you to address cumulative, aggregate
-- you know, how you define your time, your durations and such. And we
want to be able to preserve those -- a lot plants have put a lot of
thought into how they do that. A lot of it's tailored to the plants own
risk profiles, and such. It's really not a one size fits all. I think
within the constraints of this guidance, we can all meet it, but you
know, we wouldn't want the inspection process to try to drive everyone
to the same exact approach on how to do this. There's variation in the
baseline CDFs and LERFs and that has to be accepted and accommodated
through the way the risk is managed.
MR. PETRANGELO: Yes, and I failed to mention this, and I'm
glad you brought it up that the overall objective with this risk
management is what we're trying to achieve is that through the conduct
of maintenance, licensees manage their overall baseline CDF to about
where it is now and to stay around that band. Okay. That's our real
DR. POWERS: We are just asking them to do better?
MR. PETRANGELO: That's right, and it's not -- and that's
kind of the -- whether you're a ten to the minus five plant or a ten to
the minus six plant, we're trying to say keep it around where you got it
now due to maintenance, and manage that effectively to within a small
delta around that. And we have the guidelines in here, both from an
instantaneous standpoint as well as a cumulative standpoint to guide
licensees in doing that.
DR. WALLIS: Tony?
MR. PETRANGELO: Yes.
DR. WALLIS: I'd like to set a bigger perspective. It's
related to the question I asked before. I'll put it a different way.
You said this was changing should to shall essentially. That sounds
like a tougher requirement. Shall is tougher than should.
MR. PETRANGELO: It shouldn't be.
DR. WALLIS: Well, it is. It is. I will say this, and this
sounds like an increased burden.
MR. PETRANGELO: Well, you know, what we -- that's a good
question, and we looked at the regulatory analysis that the staff put
together or the rule making, and they said, basically, this is trying to
codify what you are already doing. So, there's certainly no intent, and
as the part of the rule making to make this an added burden.
DR. WALLIS: So it's really -- it's not changing anything.
Except for this should--
MR. PETRANGELO: It should not be changing.
DR. WALLIS: Nothing.
MR. PETRANGELO: What it does -- what it does is if somebody
doesn't do it later on, the staff has--
DR. WALLIS: So it is an increased burden.
MR. PETRANGELO: The regulatory -- well, they've got the
DR. WALLIS: So my point is that you are agreeing to an
increased burden because you think in some way it's necessary --
increasing necessary burden has been achieved. And this means --
implies that some criterion has been used for deciding that yes, this
increase in this burden is necessary. And the reason I'm asking these
questions is because I want to know how to decide the other side of the
coin when you come here and say, that this -- we're going to decrease
some unnecessary burden. Now, what's the criterion there? Isn't it the
same criterion? And what is that?
MR. PETRANGELO: No, that's a good question. That's a good
question. I think, and I've heard the staff answer it before that
absent this provision -- I mean, if you really just got down to what
tech specs would allow you to do, you could put yourself in some very
risk significant configurations. So I think -- and we didn't disagree
that that specter was sufficient to drive -- excuse me -- to drive the
rule making from a safety perspective.
Now, we were doing it anyway. It was in the rule. It just
said should. We treated it as a requirement.
DR. WALLIS: So this is increasing burden, which was easy to
MR. PETRANGELO: No.
MR. BRADLEY: Well, somewhere in the statements of
consideration or somewhere it said there was concern that over time
licensees might back track or under competitive pressures rethink, you
know, their programs or whatever. It was more just to capture on a --
in a permanent way what was being done to keep it from degrading -- I
think somewhere it was expressed that way.
MR. PETRANGELO: You know the dilemma you get in is unless
what -- because the plants -- I mean, we've gone through a bunch of
history now. The plants are pretty darn safe. It's very hard to cost
justify new requirements unless they don't add much burden.
DR. WALLIS: I see. Well, that's the easy ones. If
everything is as easy as that, because you're really not making much
MR. PETRANGELO: Well, you've either got to show a huge
change and say, or a small burden--
DR. WALLIS: You're going to into situations where you're
going to have to face up to defining things like necessary burden.
MR. PETRANGELO: Yes.
DR. WALLIS: Much more clearly than this one, where everyone
seems to agree it's a nice thing to do. That's well -- the only way you
can do it.
MR. BRADLEY: That's right. That's right.
MR. REINHART: If I could interject on your nickel here,
Tony. This is Mark Reinhart of the NRC staff. Our perspective of this
should to shall was really three things. We knew the industry wanted
the shall, and one of the reasons they wanted it is to get credit for
what they were doing in a regulatory space. So in a sense, it was an
efficiency. Another thing, we had put the configuration risk management
program in the technical specifications administrative control. Really,
the industry suggested back as far as 1994 that they would like to see
that come as part of the maintenance rule. So, again, it was looked at
as an efficiency -- they either had to do it under the tech specs or
under the maintenance rule, so by making that change, it was no real
addition, but it was an efficiency in having the requirement in one
place rather than two.
MR. PETRANGELO: Right.
DR. WALLIS: Maybe shall is always a better word than should,
because it's clearer.
MR. BRADLEY: Another reason to do this is -- and since Mark
got up, it just occurred to me that this paths the way to do additional
things with tech specs; that by having this program in place and a
regulatory requirement, it allows us to relook at tech specs and --
which to some degree, duplicate the function of this rule. And those
areas where this rule is the smarter way to achieve that function than
tech specs, we can look at some fairly significant changes to the
structure of tech specs. And in doing so, taking credit for this.
So there is some -- it's not all burden, you know. There is
actually some benefit to having this as a requirement versus a
MR. BARTON: Any more comments, questions of Tony or Biff?
MR. PETRANGELO: We encourage the ACRS to react positively to
MR. BARTON: We got that message. If not, thank you very
much, and, Mr. Chairman, I'll turn it back to you.
DR. POWERS: Thank you, John.
What I want to do at this point is to take a recess for 15
minutes. Come back. And I want to start by discussing what we want to
do with regard to this letter. Give some guidance. And then proceed on
with the agenda as it's presented to you. We can at this point,
dispense with the transcription.
[Whereupon, at 2:44 p.m., the meeting was recessed, to
reconvene at 8:30 a.m., Friday, November 5, 1999.]
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