ML20246M836
| ML20246M836 | |
| Person / Time | |
|---|---|
| Issue date: | 07/12/1989 |
| From: | Advisory Committee on Reactor Safeguards |
| To: | |
| References | |
| ACRS-T-1747, NUDOCS 8907190232 | |
| Download: ML20246M836 (164) | |
Text
~;
ftcga7=/ 7sf y 013l,\\W~
O.
UNITED STATES NUCLEAR REGULATORY COhDdISSION i
............---=======--========------====================.
ADVISORY COMMITTEE ON REACTOR. SAFEGUARDS In the Matter of:
)
)
Subcommittee on Generic Items )
)
O Pages: 1 through 127 p,,
brx t
y g rt.c.
- r. 5 r
. g g[
Place: Bethesda, Maryl J3
/ t i k,yI l r.
e >~
- 3 T
7"*k gIv}
- >.P'q (p.t>U6 L. :,,
Date:
July 12, 1989 LJI!,..;:;i(h.nh.
t ;,-
- 3 g
- 3 L % !L.
j HERITAGE REPORTING CORPORATION O
OBicialReporters 1220 L Street N.W., Suke 600 Washington, D.C. 20005 8907190I32 890712.
1~
PUBLIC NOTICE.BY THE l) 2 UNITED STATES NUCLEAR REGULATORY. COMMISSION'S
. 3 ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 4
July 12, 1989 0
1.
1 6
7 The contents of this' stenographic transcript of l
8 the proceedings of the United St.tes' Nuclear Regulatory 1
9 Commission's Advisory Committee on Reactor Safeguards 10 (ACRS), as reported herein, is an uncorrected record of the.
11 discussions recorded at the meeting held on the above date.
l l
12 No member of the ACRS staff and no participant at 13 this meeting accepts any responsibility for errors or i
'14 inaccuracies of statement or data contained in this 15 transcript.
-16 17 18 19 20 21 22 L
23 24 25 Heritage Reporting Corporation (202) 628-4888
___-_..mm____.-__s__..-____._m
(;
1 p
o l( )
1~
UNITED STATES NUCLEAR REGULATORY COMMISSION l'
2 ADVISORY COMMITTEE ON REACTOR' SAFEGUARDS 3
)
In the Matter of:
)
4
)
)
[
5 SUBCOMMITTEE ON GENERIC
)
ITEMS
)
6
)
7.
Wednesday,
-July 12, 1989 8
Room P-110 9
7520 Norfolk Avenue Bethesda, Maryland 10' The above-entitled matter came on for hearing, 11 pursuant to notice, at 8:30 a.m.
~12 BEFORE:
DR. CHESTER P.
SIESS O
'13 Professor Emeritus of Civil Engineering University of Illinois 14 Urbana, Illinois 15 ACRS MEMBERS PRESENT:
16 MR. CARLYLE MICHELSON Retired Principal Nuclear Engineer 17 Tennessee Valley Authority Knoxville, Tennessee.
18 and Retired Director, Office for Analysis and Evaluation of Operational Data 19 U.S.
Nuclear Regulatory Commission Washington, D.C.
20 MR. DAVID A. WARD 21 Research Manager on Special Assignment E.
I. du Pont de Nemours & Company 22 Savannah River Laboratory J
Aiken, South Carolina 23
)
()
24 25 i
HERITAGE REPORTING CORPORATION -- (202)628-4888
j.
2 l'
DR. IVAN CATTON Professor of Engineering.
P 2
-Department of Mechanical Aerospace and Nuclear Engineering 3'
School of Engineering and Applied Science University of California 4
Los Angeles, California
'5' DR. WILLIAM KERR Professor of Nuclear Engineering 6'
University of Michigan Ann Arbor, Michigan 7'
MR. CHARLES J.
WYLIE B
Retired Chief Engineer Electrical Division 9
Duke Power Company Charlotte, North Carolina 10 ACRS COGNIZANT STAFF MEMBER:
11 S.
Duraiswamy 12 NRC STAFF PRESENTERS:
- A.
Szukiewicz
-14 15 16 17 18 1
19 20 21 22 23-O 24 25 HERITAGE REPORTING CORPORATION -- (202)628-4888
3
{}
1 8 R O I E E D 1 II E S P
2 CHAIRMAN SIESS:
The meeting will come to order.
3 This is-a meeting of the ACRS Subcommittee on Generic Items.
4 I am Dr. 9iess, Subcommittee Chairman.
The other ACRS members 5.
of.the panel on my left are Ivan'Catton, William Kerr,-Forrest 6
Remick, Dave Vard, Charles Wyle, and Carlyle Michelson is in 7
the neighborhood..He will be in shortly I hope.
8 The puronse of this meeting is to discuss the' scope 9
and tasks associated with the Multiple Systems Response 10 Program, or is it responses?
11 MR. DURAISWAMY:
Responses.
12 CHAIRMAN SIESS:
More than one response--Mr. Sam
'13 Duraiswamy is the cognizant ACRS staff member on my right.
14 The rtles for participation in today's meeting were.
15 announced as part of the notice to the public in the Federal 16 Register on June 28th.
17 As usual, a transcript of the meeting is being kept 18 and will be made available as stated.in the Federal Register 19 notice, and it is requested that each speaker first identify 20 himself or herself and speak with sufficient clarity and 21 volume, and that means use the microphone, so that he or she i
22 can be readily heard.
23 We received neither written comments nor requests
()
24 for time to make oral statements from membars of the publi-.
25 I don't know that I have any introductory remarks to i
HERITAGE REPORTING CORPORATION -- (202)628-4888
4
}
1 make.
I think everybody has gotten the report itself.
It was 2
sent out--that gives the background on this.
I'm sure the 3
staff is going to review the history.
4 Any member of the Subcommittee have any comments or 5
any questions at this point?
6 If not, we will let the staff start in.
And who is l
7 going to start?
Mr. Szukiewicz, how do you pronounce it?
8 MR. MURPHY:
Very carefully!
9 MR. SZUKIEWICZ:
Good morning.
My name is Andy 10 Szukiewicz.
I'm the task manager for this program, Multiple
)
11 Systems Responses Program.
12 Today with us, with me, we have members of the staff
()
13 who would be Bob Baer, the branch chief of Engineering Issues 14 Branch, and Dale Thatcher, section leader of the Engineering 15 Issues Branch, and Warren Minners, the deputy director for the 16 division.
17 Also we have the contractor staff with us--George 18 Murphy from Oak Ridge National Laboratory, and Mike Roberts, 19 and Myron Casada of JB Associates.
20 Mike Roberts will provide the presentation on the 21 specific issues that we have identified.
22 The last time we were, we talked with the l
23 Subcommittee on this issue was August 10th of last year where
()
24 we described briefly the activities and how we would be 25 responding to the, a lot of the issues that were raised by the HERITAGE REPORTING CORPORATION -- (202)628-4888 t
5 l'.
ACRS Committee.
2-
- ( Slide ).
3 MR. SZUKIEWICZ:
The MSRP progrtm evolved from the:
j 4
concerns reparding scope limitation imposed during resolution 5
of a number of USIs, specifically A-17, system interactions, 6
'A-46, which is a USI also--these are all USIs--seismic
-7 qualification of equipment in operating nuclear plants, and i
i 8
USI A-47,. safety implications of control systems in PWR 9
nuclear power plants.
j 10 In-addition, a number of concerns were also raised
.11 from previous programs such as the environmental' equipment l
-12 qualification program, the seismic qualification program, and
'13 fire protection review program, i
14 A number of the, most of the issues that were raised' I
15 were verbal in nature, and were identified during the meetings 16 and subsequent meetings on the USIs, and a few of them also 17
.have been identified specifically by the ACRS letters on l
18 specific subject matters.
I 19 (Slide)
]
20 MR. SZUKIEWICZ:
The Multiple System Responses 21-Program objectives was to gather and review information on 22 USIs and previous programs, as I mentioned the equipment l
23 qualification program, both environmental and seismic, and the
( f 24.
fire review program, to describe the specific concerns 25 identified by the ACRS, and also identify during the review of HERITAGE REPORTING CORPORATION -- (202)628-4888
6 1
_the USIs.
2 MR. MICHELSON:
Could you clarify for me in 3
reviewing to identify these concerns, did you review them at
~4 the various subcommittee meetings held over the years relating 5
to these various issues?
Was that part of your review 6
process?
7 You said many of the concerns were stated verbally..
8 Well, that's where--they were stated verbally.
They are 9
actually also written down in the minutes of the meetings.
I 10 just wondered did you actually read those minutes?
11 MR. CASADA:
Myron Casada--I think, if I can address 12 that, I think early on we tried to use the transcripts to some 13 extent.
We found that notes from the people that were making
-14 the presentation, when someone raised a question, we-found 15 that what the staff had checked during the meetings was useful
.16 to us.
Trying to understand the transcripts themselves was 17 much more difficult.
l l
18 MR. MICHELSON:
Yes, but there are minutes of the 19 meetings also written by our staff people.
Do you ever read 20 those?
Those are certainly available.
21 MR. WARD:
You don't get those you say?
22 MR. MICHELSON:
If they don't understand the 23 transcripts, I think they might understand the minutes.
The
()
24 staff person who wrote them knew what wa-going on.
I don't 25 expect you to read the transcripts.
L HERITAGE REPORTING CORPORATION -- (202)628-4888 L
7
{
_1 MR. SZUKIEWITZ:
I don't recall any minutes that we 2
received on this.
3 MR. MICHELSON:
I agree some of the transcripts are 4
hard to follow.
I wouldn't necessari3y expect this review to 5
go back and read every transcript, although that's what I 6
wondered, but I did expect you to go back and read the minutes 7
of the meetings at least.
8 DR. KERR:
I would guess if you read the minutes of l
9 the meeting, you would still be confused because I attend a l
l 10 good many of those meetings and I.was certainly confused of l
1 11 course, in the course of discussions.
12 CHAIRMAN SIESS:
The minutes have a slight
()
l'3 advantage.
They represent the first level, the staff 14 engineer's interpretation, and then they are supposed to be 15 reviewed by the Subcommittee members.
What depth, I'm not 16 sure.
It depends.
17 MR. MICHELSON:
Did you review the minutes then?
18 Did not.
19 MR. BAER:
In my 18 years here, I don't know that I 20 have ever seen a set of ACRS minutes prepared by the ACRS 21 staff.
l l
22 MR. WARD:
That's right.
If I look at the 23 distribution, they don't seem to go to the staff.
l
(}
24 CHAIRMAN SIESS:
It is a public document.
This is a j
25 federal advisory committee.
All of our meetings are open and HERITAGE REPORTING CORPORATION -- (202)628-4888 L---_-_---
8' t{~
'1 all of'our minutes are available to anybody that wants them.
2 MR. MICHELSON:
I guess I incorrectly assumed the 3
staff was aware that we write minutes of every. meeting.
4 MR. WARD:
Let me ask why we.can't send copies of l
5-the minutes to the people on the staff who are directly l
6
' involved?
7-MR. DURAISWAMY:
The transcript, we send them the.
8.
transcripts.
The minutes, because under the minutes--
9 MR. WARD:
If they don't ask for it, why don't we 10 send it to them?
11 MR. MICHELSON:
.I think it would be useful.
I find 12 the minutes many times much more helpful than the transseript.
lk 13 DR. KERR:
There goes another tree!
14 MR. MICHELSON:
At any rate, I got the answer.
A 15 couple of things that I have found missing were in minutes.
16 MR. WARD:
Let's not send them the transcript.
Send l
17 them the minutes.
That will save--
18 CHAIRMAN SIESS:
Well, I don't know which-is worse.
19 I guess the worst thing to do would be to ask the ACRS what it 20 meant.
Theoretically that would be the best way to find.out 21 what the ACRS is concerned about.
What you are really getting 22 is concerns expressed by ACRS members, which is legitimate.
23 MR. SZUKIEWICZ:
That is correct.
()
24 CHAIRMAN SIESS:
To take those as seriously as you 25 wish, but some of your references are ACRS letters.
1 i
HERITAGE REPORTING CORPORATION -.(202)628-4888 i
9 i([
l' MR. SZUKIEWICZ:
That is correct, ycs.
2 CHAIRMAN SIESS:
Now those may be no less cryptic.
3 At least they are the Committee's position.
4 MR. SZUKIEWICZ:
This is correct, and this is one of 5
the main reasons we are here to discuss these programs today 6
is that we have attempted to describe the concerns as best we 7
could, and now we would like to discuss them with you and to 8
solicit additional comments if we, if we interpreted something 9
that was not the intent of the individuals.
10 CHAIRMAN SIESS:
We don't have enough time, but I 11 suspect that half a day is not going to get that far.
12 Somebody once described ACRS letters as terse, technical and
(
13 cryptic.
Okay.
Your objective today is to tell us what you 14 have done, and to some extent try to find out whether you have 15 interpreted the ACRS concerns correctly.
16 MR. SZUKIEWICZ:
Exactly.
That's the main objective 17 of this program, of this meeting today, i
18 The MSRP objectives, to continue with the l
19 discussion, is to also develop and further define the concerns 20 as specified, to identify and define the concerns as specific i
21 potential safety issues.
A number of concerns that we have 22 identified were very, very similar, and they were grouped into 23 specific safety issues.
~()
l 24 The end objective is to provide information so that 25 we can identify, prioritize these issues, in a formal fashion, HERITAGE REPORTING CORPORATION -- (202)628-4888
_______________________________________________________J
10
.f')i 1
and determine what we are going to be doing with these 2
programs.
3 The prioritization will be done by the NRC.
This is 4
basically a Phase 2 of this activity, but it is not part of 5
the.MSRP scope of this particular program.
6 We intend to submit it to another division and to 7
work with them in prioritizing these particular issues.
8 MR, MICHELSON.:
Will they also attempt then to group 9
some of these related issues together for a single generic 10 issue?
Is that it?
11 MR. SZUKIEWICZ:
That may be a possibility, that is 12 correct.
We tried as best we could to identify this 13 particular activity.
14 (Slide) 15 MR. SZUKIEWICZ:
As mentioned, we developed a draft 16 report in June of this year, and.on June 8th we submitted it 17 to the ACRS subcommittee for their review..
18 The purpose, as I mentioned, is to discuss this 19 report and to solicit the ACRS comments.
We intend to 20 incorporate any additional comments we received today and 21 issue a final report sometime in September, October timeframe 22 of this year, and then as I mentioned, we will then prioritize 23 these issues and we will come back and discuss these i,ssues
()
24 with you to give you the status of the prioritization process.
25 (Slide)
HERITAGE REPORTING CORPORATION -- (202)628-4888
11 1
ML. MICHELSON:
Are'you going to tell us later on
(-).
V 2
what kind of a schedule you think you will prioritize these.
3 issues?
4 HR. SZUKIEWICZ:
Right now, we, we are not really 5
prepared to talk about the schedule.
6 MR. MICHELSON:
Are we talking about one year, five 7
years, something in between?
Are we talking about the next 8
few. months?
9 CHAIRMAN SIESS:
What is your backlog, Warren?
10 MR. MINNERS:
I guess I don't know the answer to 11 that question.
12 CHAIRMAN SIESS:
That's another branch?
( ).
13 MR. MINNERS:
Yep.
14 CHAIRMAN SIESS:
Can you find out before 12:30 15 today?
16 MR. MINNERS:
I will try to.
17 MR. MICHELSON:
An approximate idea--are we talking 18 about within a year or five years or what?
It is not, not i
19 clear.
20 (Slide) 21 MR. SZUKIEWICZ:
In summary, in the MSRP program, we 22
-identified 31 concerns.
These concerns have been provided and 23 described in Sections 2 through 6 of the report.
Of these
(
24 concerns, we have combined them into 21 potential safety 25 issues, and these are identified in Section 7 of the report.
HERITAGE REPORTING CORPORATION -- (202)628-4888
12
{}l 1
We-also believe that ten of these safety issues are already 2'
. addressed in existing programs, and we will discuss-this 3
later.
4 (Slide) 5 MR. MICHELSON:
Most of the others, by the way, were 6
already addressed in the testing programs, too.
They just got-7 removed again from the program, and are going to get 8
reprioritized once more.
It is just a delaying action.
9 MR., SZUKIEWICZ:
We are prepared to give you some of 10 the status of that and some of the objectives.
I agree that 11 some of these programs have been prioritized.
In some cases, 12 a number of them are still in the process to be prioritized 13 and we have identified those for you, too.
14 Again, the presentation of this particular objective 15 is to describe the scope and content of the MSRP program to 16 date, discuss the identified potential safety issues, and tr 17 solicit your comments.
-18 I would like to turn over the program right now to 19 our contractor.
JB Associates did most of the work in 20 coordinating and reviewing and investigating the issues and 21 trying to identify and best describe them.
We will now talk i
22 about the specify issues.
23 I would like to introduce Mike Roberts who will
()
24 conduct the, the next discussion.
Mike?
25 MR. ROBERTS:
Good morning, gen tl emen.
My name is HERITAGE REPORTING CORPORATION -- (202)628-4888 4
I
r ll 13
]
i j
(.
'1 Mike ~ Roberts.
Most of the work that was done on this project 2-at Oak Ridge National Lab was done by a number of people at 3
the lab, including myself.
As Andy has already indicated, the 4
objectives, overall objectives of this presentation are to k
5 describe to the ACRS the scope and the content of the MSRP 6'
program, to discuss and identify potential safety issues which l
7 were developed from a whole series of concerns that the ACRS 8
has voiced over the years as well as concerns that have come l'
9 about as a result of different USIs and GSIs.
10'
'We are also here to solicit some ACRS comments and 11 just to provide some.eneral information as to what veLL into 12 developing these issues.
.( )
13 The purpose of our effort at Oak Ridge was to gather l
14 review documentation from the USIs and other programs, as Andy l
15 has already indicated, from that documentation, to describe l
16 potential saf ety concerns that have been expressed by the ACRS 17 or other GSIs.
18-In addition, we have tried to provide some l
19 information to allow the NRC staff to make an assessment of 20 the relative safety significance of the concerns through the 21 established prioritization process.
We did not make any 22 judgments regarding the validity of the concerns that were 23 expressed by the ACRS or others.
We examined the concerns,
()'
I 24 documenting them and defining the issues as specifically as 25 possible.
l HERITAGE REPORTING CORPORATION -- (202)628-4888
.1 114
- f 1
The remainder of my presentation is going to be 2
devoted to one describing the potential safety issues th c 3-were developed from the concerns; two, discussing regulations 4
.and guidance documents that may be addressing these issues or 5
.may not be addressing these issues, discuss the NRC and 6
industry programs that in whole or in'part appear to be l
l L
7 addressing the issues, and then try to give an explanation of 8
where we think this issue stands in terms of the 9
prioritization process.
l 10 Before I get into that, I would like to mention that l
1 11 you all should have copies of all of the slides that we are 12 presenting here.
Some of these may not show up in entirety on
(
13 this screen, so I hope you will bear with us there.
14 MR. MICHELSON:
Before you leave that slide, the 15 last bullet talks about soliciting comments.
16 What did you do to solicit comments?
17 MR. ROBERTS:
The whole idea here is to try and 18 solicit as a result of this presentation, to going through 19 these issues here, we would like to get some feedback from the 20 ACRS.
21 MR. MICHELSON:
Well, one of the recommendations 22 ACRS made some time ago was that they thought a part of tais 23 program ought to include going out and talking to various
()
24 people about are there other issues that perhaps need to be on 25 this list?
The ACRS shouldn't be the sole source of some of I
HERITAGE REPORTING CORPORATION -- (202)628-4888 w__-________-___-______--__
15 l-
)
1-
.these concerns, and we recommended that in our earlier letter.
2 Did you ever do anything about it?
3' MR. ROBERTS:
What we have, one of the things.we 4.
have tried to do, we tried in many instances here not'to 5
specialize a particular concern that the ACRS came up with..
6 We did try to think in terms of what the ACRS was.really 7
getting at rather than trying to think in specifics.
8 Now--
9 MR. MICHELSON:
Perhaps you missed my point, My 10-point is that I think it is nice if you try go back and pull 11 together our' comments, but we have also indicated that we 12 thought that this was a broader subject than perhaps we had 13 considered, and you need to go to talk to other experts about 14 system interaction questions and see what some of their~ views 15 are, and this was in our letter, our last letter or pr evious 16 one to that.
17 MR. DURAISWAMY:
It is not in the letter.
It is in 18 the minutes.
19 MR. MICHELSON:
We wrote a letter.
20 MR. CASADA:
That's a letter we have never seen if 21 it is written.
22 CHAIRMAN SIESS:
Couldn't find the letter.
23 MR. DURAISWAMY:
That's in the transcripts also.
()
24 MR. SZUKIEWICZ:
Although the majority--
25 MR. MICHELSON:
It is in the minutes of the HERITAGE REPORTING CORPORATION -- (202)628-4888
16
'h 1
meeting.
It is in the transcript.
j
\\J.
1 2
-CHAIRMAN SIESS:
It was suggested by ACRSl members.at.
3 the meeting on, a consultant at the meeting, that you should 4
seek people with operating experience for other types of 5
interactions'that had occurred rather than just relying on 6
this, on the stuff that we bring it up.
7 MR. SZUKIEWICZ:
Actually we did interface with.the.
8 other groups and there-are a number of. issues that were 9
identified.
10 CHAIRMAN SIESS:
What other groups?
11 MR. SZUKIEWICZ:
Fire protection people, we went 12
.out--
()
13 CHAIRMAN SIESS:
With operating experie:.ce?
Or 14 people like yourself?
15 MR. SZUKIEWICZ:
These were the experts in fire 16 protection.
We did not go outside the--
17 MR. BAER:
We doesn't go out to utilities, no.
18 DR. KERR:
Mr. Chairman, I hate to see us establish 19 a precedent that the minutes of Subcommittee meetings 20 represent reports of the ACRS.
21 CHAIRMAN SIESS:
No.
I tried to make that point 22 earlier.
The concerns describe concerns even if they were 23 expressed by an individual member, which is quite legitimate, 24 but it was suggested that as good a source as that might be,
(
25 there were other people out there that had been operating i
HERITAGE REPORTING CORPORATION -- (202)628-4888
17 o
9
'1 plants and had seen things happen, that the same general t
2-nature, and that it might be well to go out and find out what l
3 other people have seen in the way of these interactions, and 4
the answer I get is that that is, that has not been done.
5 MR. MURPHY:
No, no.
George Murphy, ORNL--if you 6
will look at the very back of the report, there is a 7
voluminous list of references, and in those references you 8
will see that we have went to many reports--pick an issue, say 9
fire, and pursue that list, you will see that there are many 10 reports outside.the industry published in Fire Journal, other 11 places, and gathered information other than from within NRC.
12 If you.look through the report, you will also see we
()
13 have referenced studies of operating experience that we have 14 done at ORNL, and other laboratories have done, too.
15 CHAIRMAN SIESS:
So you looked-at records of 16 operating experience?
17 MR. MURPHY:
Reports of operating experience 4 7 a 18 given area.
19 MR. MICHELSON:
Since the subject here today is 20 systems interaction, when we get to the fire part, you can 21 point out to me some of the system interaction feedback that-22 you got from these other.
23 MR. BAER:
The subject is not merely system
(}
24 interactions.
I know there is a bunch of concerns out there, 25 but we had difficulty over the years trying to get those HERITAGE REPORTING CORPORATION -- (202)628-4888
L
[;
18
[()
I concerns to a point where one could sit'down and prioritize L
2 them, and I'think it is broader than just system interaction.
3 MR..MICHELSON:
I thought that we were trying to 4
focus on our system interaction question.
5 CHAIRMAN SIESS:
Nope.
6 MR. MICHELSON:
All the concerns we had.
7 CHAIRMAN SIESS:
Some of the concerns come from 8
A-17, which is systems interaction; some coming from A-46, 9
A-47, and the five areas, i
10 MR. MICHELSON:
But the point, Chet, is that even i
11 our seismic, it is only focusing on the system interaction 12 effects, not on all the seismic concerns we ever had.
This is 13 not a seismic concern document.
It is a system interaction 14 document and seismic is part of it.
15 CHAIRMAN SIESS:
Well, I think that's something that 16 we might want to explore because if you believe that all of 17 these things are simply examples of systems interaction, it-18 might be helpful to discuss, debate that with the staff and 19 their contractors, i
20-They have divided them up into 21 categories of l
l l
21 concerns, and systems interaction was only one category.
I
)
l 22 think that has been part of the problem.
We lump so much 23 stuff into A-17, there was no way of resolving it, and when
()
24 they tried to break A-17 down into bite-sized pieces that 25 could be analyzed and resolved, we objected that they left out i
HERITAGE REPORTING CORPORATION -- (202)628-4888
{
1-19
( )-
l' some, so it is a sort of a dilemma that we lump everything 2
into a USI that has to be resolved because Congress wants to 3
know, or do we try to break the subject of, general heading of 4
systems interaction down into specific types of interactions, 5
which inevitably will still leave some other types of 6
interactions on the grass?
Either they haven't happened yet,
~
7 or we haven't' thought of them yet.
So here is the prob 1'em.
I 8
know what the staff trying to do.
9 MR. CASADA:
We have got some 21 issues here.
I 1
10 recommend we throw out five or six and talk about them and L
11
.then we can see what we think they are, whether they are 12 systems interaction or whatever you care to call them,.but I-13 do think it would be--
14 CHAIRMAN SIESS:
It is not a question of that.
The 15 point I was trying to make, I'm sure addressed more to the 16 staff than to the contractor, even if six of those are systems 17 interaction, the question then is do you treat them as six new 18 generic issues, or do you dump them back into the big pot 19 called systems interactions which is never going to be solved?
20 S3-tems interactions we have said I'm sure in.a 21 letter is an ongoing process.
We are going to continue to 22 discover, we will continue to find out what to do about it.
23 And it was a mistake-to ever lump them into one big area, say
()
24 to the Congress this is then unresolved safety issue, if you 25 give us enough money, we are going to resolve it.
HERITAGE REPORTING CORPORATION -- (202)628-4888
20 l
1-If systems interaction in the broad sense is never 2'
going to be resolved philosophically, or technically, or 3
procedurally, does the staff break it down into bites, 21 or 4
six or eight or whatever, and work on it?
I think that's the 5
question that we have got to help the staff decide.
'6-MR. MINNERS:
That's the function of the 7
prioritization process is to take these multiple issues and 8
combine them in what people think is the optimum way to 9
resolution, and that certainly will not mean take all 21, 10 dumping them into one issue called systems interaction.
11 CHAIRMAN SIESS:
That's what we did ten years ago.
12 MR. MINNERS:
I think we found that was a mistake,
(
13 It was too big a bite and doesn't work.
j l
14-CHAIRMAN SIESS:
Certainly found it was a mistake 15 when you came into the ACRS and said we resolved systems 16 interaction, and the Committee came back and said you might 17 think you have, but you only resolved portions of it, and at 16 that point you said well, what is left over, we will try to 19 handle in the system responses program.
Now that's why Carl 20 is looking at this as simply an extension of systems 21 interactions.
22 So let's go ahead, but what you do with it in the 23 end, whether you reopen A-17 or end up with 21 new ones or l
()
24 what, neither one is going to finish the job because next 25 month somebody will think of something else or something will HERITAGE REPORTING CORPORATION -- (202)623-4888 L___________
j i
21 1
happen and we will have to go out and look and see how common 2
it is, how general it is and so forth.
3 MR. MINNERS:
That's why we have a generic issue 4
program.
5 CHAIRMAN SIESS:
The worst thing we can do is close 6
the door on systems interaction because they are not going to l
7 go away just because we close the door.
j 8
MR. MINNERS:
I think what we are trying to say here
)
1 1
9 is that we don't need a separate program for systems 10 interaction.
We are doing this program because we happen to 11 have a pile of issues that got identified at one time.
This 12 seems like an efficient way of handling it, but the whole lll 13 purpose of the generic issues program is to take care of 14 issues such as identified system interactions, and get them 15 rolling through the resolution process.
That's the proper way 16 of getting the new issues resolved.
17 CHAIRMAN SIESS:
All right.
18 MR. ROBERTS; I think what we are going to find is 19 we did try to focus on a particular issue that may have been 20 developed, may have smatterings of the A-17 or smatterings of 21 A-46 or smatterings of A-47, carryover concerns in it, and so 22 that's something that I wanted to say up front.
23 I think what you are going to find, because any one ggg 24 issue may not be totally addressing one particular aspects or 25 concern in A-17, there may be another portion of it that we HERITAGE REPORTING CORPORATION -- (202)628-4888
22
/~g.
I are trying to address in another issue to be developed, so I
\\ /-
2 hope you will bear with us.
3 CHAIRMAN SIESS:
A-17, A-17 is what is signed off 4
on,.isn't it.
5.
MR. ROBERTS:
I'm sorry.
I guess I should say 6
concerns that came out of concerns that were not in the 7
resolution of A-17 that the ACRS may have come up with.
8 CHAIRMAN SIESS:
A-17 is quote, resolved?
9 MR. ROBERTS:
It is resolved, but--
10 MR. MINNERS:
Not quite.
Il MR. ROBERTS:
It is--as you said, systems 12 interactions in general aren't resolved.
()
13 CHAIRMAN SIESS:
Systems interaction do find.a 14 mechanism for-keeping it active as a series of generic issues.
15 That's your approach.
16 MR. ROBERTS:,One of the issues that was developed 17 out of a concern that was not within the resolution of USI-17 18 dealt with potential for operator acts of omission and 19 commission on components potentially affecting redundant 20 trains, manufacturing errors in components that could possibly 21 affect the redundant trains of equipment and installation, 22 maintenance, or testing errors that may be repeated on 23 redundant trains of safety-related components.
24 There are a number of regulations and guidance
}
l 25 documents that do appear to somewhat address this issue--10 HERITAGE REPORTING CORPORATION -- (202)628-4888 lL
23
-( }
1 CFR 21 requires manufacturers to report fabrication errors, 2
and also requires the establishment of QA programs by the 3
manufactutor.
4 Reg Guide 1.123 provides guidance for complying with 5
10 CFR 50, Appendix B, with regard to control of procurement 6
of manufactured items.
Also establishes overall QA objectives 7.
for design, construction, operation of components in nuclear 8
facilities-.
9 There also have been a number of other reg guides 10 and NUREGs that have provided guidance for reducing other 11 errors.
The NRC LER Review Branch had identified potential 12 safety problems and on occasion issues bulletins and notices.
()
13 One that we presented here as an example is Information 14 Bulletin 85-03, which is an example of continuing NRC staff 15 involvement in trying to identified common cause problems.
16 CHAIRMAN SIESS:
Excuse me.
Put that back on just a
'17 minute.
If, if you had gone to say commonwealth Edison and 18 asked them what do you do t3 prevent common cause failures 39 related to human errors of the type you have described by the 20 first bullet, do you think they would come up with that list 21 you have got at the bottom of the screen?
l 22 MR. CASADA:
I think what they would come up with 23 are the operator procedures, and the standard--and standard
()
24 operating procedures, and for maintenance and various 25 activities that they do, that grow out of these requirements.
HERITAGE REPORTING CORPORATION -- (202)628-4888
24 l
0-1 I mean the people in the plant don't live day-to-day 1
2 with these document numbers, they live day-to-day with-their l
~
' operating procedures, and what their plant Operation Committee l
3 4
tells them and new they have to do their business and all of 5
that group over the years out of these documents.
N
.R.
ROBERTS:
It represents the baseline' regulations.
6 M
7 and guidance documents in these areas that we see.
8 MR. CASADA:
They tell you about the testing 9
required after maintenance is done to make sure that you don't 10 introduce a common mode failure.
They tell you about the 11 requirements to or independent checkoff of an operating 12 function, those kinds of things.
()
13 CHAIRMAN SIESS:
Are you saying they are, operating 14 procedures which is a stack like so--
15 MR. CASADA:
Or larger.
16.
CHAIRMAN SIESS:
Is integration or a synthesis of 17 these NRC requirements?
18 MR. CASADA:
Yes, sir.
19 MR. ROBERTS:
There are some indu.stry, there is some 20 industry involvement in this area.
INPO has established the-21 human performance evaluation system for evaluating performance 22 in areas of operation installation, maintenance, testing.
23 The NRC is also establishing the human factors 24 program which is, the plan for this program is described in 25 NUREG 0985 which will be addressing installation, maintenance HERITAGE REPORTING CORPORATION -- (202)628-4888
25 1
and testing. errors related to. training, procedures, staffing
.J 2
qualification.
h 3.
Considering all of these' items,.it appears that l:
4-these concerns, or this concern is addressed by the existing 5
regulations, guidance and programs, but this is goir.g to have l
6 to be' confirmed in the prioritization process, and as a 7
qualifier here, every one of the issues that we present today-8 are going to end'with either to be confirmed in the 9
prioritization process, or to be priori: ?ed.
10 Now to be confirmed in the prioritization process-11 means that we believe that these issues may be addressed by 12 existing programs, and the prioritization process will confirm I) 13 that.
We believe the prioritization will confirm that fact, 14 or there may be issues that are just to be prioritized in 15 which.we don't have any--well, really don't have a good. feel
'16 for whether we believe this issue is adequately addressed by 17 regulation or existing programs, and it is going to be up to 18 the, up to the prioritization staff to make a judgment there.
19 CHAIRMAN SIESS:
You know, it is interesting that 20 everything you have got here relates to eliminating the human 21 errors rather than eliminating the consequences of human 22 errors.
23 Ts that deliberate, or is that just the way it comes
()
24 out?
25 MR. ROBERTS:
The way the concern was specified, we, i
HERITAGE REPORTING CORPORATION -- (202)f- -4888
1' 26 r'\\
1-
-]V ;
it was more,fwe interpreted it as eliminating the cause rather
[
2 than dealing with the consequences.
l
'3 CHAIRMAN-SIESS:
The concerns would be eliminated if.
l 4
we'followed'the Japanese practice, for example, of doing-5 minimum of maintenance at.d surveillance testing during 6
operation.
L 7
MR. MURPHY:
These are common cause failures.
8 Davis-Besse is a motor-operated valve situation, things like 9
that.-
That could happen to the Japanese, too.
10 CHAIRMAN SIESS:
Has it?
11 MR. MURPHY:
I'm sure it has.
We don't have a whole 12 lot of their operating information.
We don't get that
(
13 nitty-gritty information we would like to get from them.
14 MR. MINNERS:
You know, in making comments on 15 issues, one of the more helpful things that define an issue is 16 some, you come up with some conceptual fix, and this is a 17 particularly difficult issue to understand.
If somebody has a 18 more specific fix that they think can do something important, 19 that this would be a great comment to have because that would 20 really illuminate the problem.
21 I personally don't see anytning that I could think 22 of that would fix this except more of the same, which I'm not 23 stre that would fix it, either.
()
24 CHAIRMAN SIESS:
More what?
25.
MR. MINNERS:
More of the same, and your question, j
HERITAGE REPORTING CORPORATION -- (202)628-4888 1
27 f( }.
1~
your comment is interesting, but then.again, if you can make 2'
it more specific--is that your thing?
3 CHAIRMAN SIESS:
I'm not sure.
Illun.inating human 4
errors is obviously a solution.
Unfortunately, I don't 5
believe it is possible.
You can reduce them, but can't 6
eliminate them.
7 MR. MINNERS:
Your suggestion could be evaluated.
8 Somebody could go through a process.
9 CHAIRMAN SIESS:
Nobody has thought of any way of 10 reducing the consequences of human errors?
11 MR. MINNERS:
No.
Reducing the consequences of 12 common cause; we have redundant, diverse systems now that
)
13 reduce the consequences of human errors and other assignments.
14 CHAIRMAN SIESS:
So if you had six redundant 15 systems, it would be very difficult for them to make--
16 MR. MINNERS:
More dif :icult to make a common cause 17 failure.
18 CHAIRMAN SIESS:
Yes.
l 19 MR. WARD:
No.
20 MR. BAER; I personally believe--
21 CHAIRMAN SIESS:
Some cases you could have diesels 22 torn out all in six-month period.
You spread it out--
23 MR. BAER:
If that's the common cause area you are
()
24 thinking about, if you are thinking about operator errors of 25 comission, I guess I am personally convinced if the operator HERITAGE REPORTING CORPORATION -- (202)628-488d
28
_1-thinks a certain course of--is the.right action, shut off
~
2-safety injection,-it is going to shut off one train, shut off
[
-3 two or three or eight.
I mean if he is going--
4 CHAIRMAN SIESS:
Having happened in Pennsylvania.
'5 MR. BAER:
That wasn't multiple errors to my mind.
6 That was one error.
7
~ CHAIRMAN SIESS:
I just wanted to know if you 8
thought about two ways of going about the thing..
9 MR. ROBERTS:
I guess as an observation it in 10
. perhaps much easier to deal with the cause than it is the 11 effect, especially when you are talking about common cause 12 failures, because if you are trying to design against say
(
13 having three pumps fail, if you have a manufacturing error 14 that is a result of some human element, it is'a common cause 15 failure.
Mayb'e all, maybe you have to have one of those pumps 16 futetioning, but the common cause failure is going to get all 17 th:!e e, and if you can't live with the fact of losing all three 18 of them, it seems to me it is much easier to deal with the 19 cause than it is to affect as an example.
Common cause j
20 failure gets the redundancy.
You have got to have diverse--
21 CHAIRMAN SIESS:
There are always ways of disabling 22 a diverse system by human action.
bet's f ace i t.
People can 23 do anything.
()
24 MR. ROBERTS:
I agree.
25 (Slide)
I l
HERITAGE REPORTING CORPORATION -- (202)628-4888
29 1
MR. ROBERTS:
The next issue that I have got up here y
2 deals with potential for' multiple simultaneous failures in 3-non-safety related control systems to have an adverse effect 4
.on safety-related' protection systems.
5 This is a rather broad issue, and I would like to 6
say up front that there are some very specific cases of this 7
type of dependency that we have drafted into separate issues 8
here.
9 In particular, we have an issue where we are dealing 10 with HVAC failures resulting in these kinds of interactions, 11 digital computer :ontrol systems dealing with these kind of 12 interactions, fire events causing this flooding and seismic,
~( /
13 and so this issue here we envision as trying to take care more 14 of other types of functional interactions that aren't related 15 to the items I just mentioned, j
16 However, the general requirements and programs that i
17 are in place nere may be applicable to regulations or l
18 certainly going to be applicable as there may be some programs 19 that are in addition applicable to these specific issues that 20 I will discuss in a little while.
[-
21 DR. KERR:
I don't understand your last statement.
22 You say the general programs operation may be applicable to j
23 the regulation or something?
()
24 MR. ROBERTS:
The regulations Tegarding separation l
25 and isolation, separation of control and proteccion systems, HERITAGE REPORTING CORPORATION -- (202)628-4888
.1
'f; a
30 1
are going to be applicable to the other issues I want to talk 2
about where you have got dependencies between internal l
3 protection systems.
4 DR. KERR:
Applicable in the sense they would solve 5
the problem?
6 MR. ROBERTS:
No.
I'm just saying--see, let me 7-state right now we are not trying to solve the problem.
We 8
are trying, we tried to look and find regulations.
9 DR.'KERR:
I am trying to understand what is the 10 meaning of the word applicable?
11 MR. ROBERTS:
Meaning there is some relationship to 12 that issue.
I'm not saying it is a positive relationship.
It-
'( )
E13 may'be a negative relationship.
It may be that the 14 regulation, a regulation is saying that this, this particular 15 issue, this does not necessarily have to be looked at or is 16 not necessarily spelled out in the regulation as such.
17-For example, General Design Criteria 24, which 18 requires separation of control' and protection systems, only 19 does so with regard to a single failure of a control system 20 component.
)
21 What we are talking about here are multiple failures 22 of control, of control system c mponents affecting
)
23 safety-related protection systems, so GDC 24 would not apply.
]
()
24 It is not an adequate, it <oes not adequately address that
)
25 issue, and that's what I mean by the regulation side of what I HERITAGE REPORTING CORPORATION -- (202)628-4888
31 1
mentioned.
2.
DR. KERR:
You are saying the existing regulation is 3
obsolete?
4 MR. ROBERTS:
They may or may not be.
In some 5
cases, the regulation may in a general sense tapdance around 6
the issue, and you may be able to imply that that's being L
7 covered, that' regulation is corrs
'ly applicable and is 8
attempting to address that particular issue, 9
In other cases, the regulations aren't telling 10 you--they are telling you that one failure is all to look at, 11 and you are not going to look at two failures.
There is not a 12 requirement there that says you have to do that.
()
13
.MR, MURPHY:
The key words are proper when 14 implementation is required to ensure adequate protection.
I 15 think that's where the key to this lies is how and who 16 implements the general design criteria, the IEEE standards, 17 the reg guides, notices and bulletins that have been issued in 18 regard to this issue.
I guess that probably goes for every 19 issue.
20 CHAIRMAN SIESS:
So that explains why multiple is in 21 there?
22 MR. ROBERTS:
That is correct.
23 CHAIRMAN SIESS:
If the plant has been designed and t
l
(}
24 is operated in accordance with the existing regulations, 25 single failures should not be a problem?
HERITAGE REPORTING CORPORATION -- (202)628-4888
i 32 1((
l' MR.. ROBERTS:
According to the regulations they e
v' 2
shouldn't be, but I'm not going to say thet they are not going 3-to be because I'm in no position to make that-ll 4
CHAIRMAN SIESS:
We don't know whether they ever 5
have been a problem.
6 MR. ROBERTS:
Teat's not something that we-7 investigated.
l>
8 CHAIRMAN SIESS:
That's what, the previous question 9
about looking at operating experience.
Is there any--
10 MR. BAER:
As part of A-47, this was looked.at 11 pretty extensively and we were never able to identify a 12 situation where control system failures wiped out multiple
)
13 protection systems.
You know, and you know there is a fair j
14 amount of operating experience now.
We werent able.to 15-identify any such events at that time, but that isn't what we 16 asked the contractor to do in this case.
17 CHAIRMAN SIESS:
Now that explains.why multiple is 18 in there.
The other adjective, simultaneous--
19 DR. KERR:
het me follow up a little bit on that.
20 Bob, I don't know what you mean by wiping out, but you 21 certainly have identified situations in which various control 22 systems challenge safety systems.
23 Now since safety systems are supposed to be highly
'( )
24 reliable. it may take quite a lot of experience to determine 25 whether they can be wiped out or not, so tihe f act that you HERITAGE REPORTING CORPORATION -- (2021628-4888
33 (f
1-have.not'seen wipeor' I'think should be--it is. import-Jt, but 2-it does not completely resolve the issue of whether this is 3-interaction we want to look at.
4 MR. BAER:
No.
I'm not saying that it is not 5
possible.
I'm just saying that the operating experience to 6
date--I ought to go back a step.
7 As part of the resolution of A-47, there was an 8
assumption made initially that plants had been designed 9-correctly and designs have been implemented such that control 10 system failures would not affect multiple protection systems, 11 but mnitiple protection trains, yes, that there be at least 12 one remaining protection system train available even though 13 there were control system errors.
14 We went back and looked at LERs to see if we found 15 any, any operating experience that indicated that was not the 16 case, and we were unable to find any events that indicated 17 that there wasn't at least one train of protection system 18 left.
19 That doesn't mean yes, you are correct that it 20 couldn't happen in the future.
The operating data today, to 21' date, support that, you know, it is a relatively low 22 probability.
23 DR. EERR:
There is also a situation which although
()
24 say SCRAM system may operate, and therefore say that system is 25 okay, the SCRAM itself may get into a situation in which t
34 1
either the risk is increased or malfuncton, 2
MR. BAER:
Oh, yes, definitely.
3 DR. KERR:
It is a total effect of the failure of 4'
the control systems on the risk of the plant it seems to me 5'
that we are interested in, and in the existing regulations,
- 6 you know, it is really not looked at, simply it does, as you 7
say, look to see whether one wipes out the safety systems.
8 MR. BAER:
It is not looked at directly, but one of 9
the performance indicators that is followed pretty closely is 10 the number of trips per year, which you know, most of'those I
11' trip, certainly a large fraction of them are a result of some 12 sort of control system failure or control system operator
()
13 interface, and it has been gradually declining drastically, 14 has been declining.
15 CHAIRMAN SIESS:
Now I am. confused.
We have 16 redundant protection systems, and are you saying that the 17 system is never taken out more than one, but the words 18 multiple in that statement refers to multiple failures in the 19 control systems?
20 MR. CASADA:
That was the way the concern of the 21 ACRS was because traditionally what analysis looked at is 22 single failures in the control system, can it affect more than 23 one safety-related or protection system?
And the answer to
()
24 that typically has been no, and the concern that was stated is 25 yes, but you know, if we don't have as much control, as much HERITAGE REPORTING CORPORATION -- (202)628-4888
35 I1 1
care taken with control systems, maybe they are more likely to v
2 have multiple failures and could multiple failures affect 3
that?
4 MR. SZUKIEWICZ:
in A-47, we looked at multiple 5
failures, and we ran a number of it, but we assumed that at 6
least one channel of protection would be available.
We did 7
not go into the in-depth review t-o identify if multiple system 8
failures could indeed degrade both redundant trains, and as a 9
result of the comments, we, because of that limitation on 10 A-47, we decided we will go back and take a closer look 11 whether we should look at multiple failures to see if they can 12 knock out redundant trains.
That's the focus of this.
(~)'t w.
13 CHAIRMAN SIESS:
Do you think those five items up 14 there are sufficient to rule that out now?
15 MR. ROBERTS:
No.
We are not making any claim at 16 all here.
We are saying the bottom line on this issues is--
j 1
17 MR. BAER:
Related, but not necessarily sufficient.
18 MR. ROBERTS:
That is correct.
j 19 CHAIRMAN SIESS:
The status says that, it seems to j
20 say to me that the regulations and guidance should prevent l
21 this provided it is properly implemented.
22 MR. ROBERTS:
That should be qualified, that the 1
23 issue appears to be addressed only from a single control f$i 24 system failure standpoint, and I apologi7e.
That's a--
l l
25 CHAIRMAN SIESS:
As I read the status, it sort of is HERITAGE REPORTING CORPORATION -- (202)628-4888
36 L ()
1 saying'this is what--if people do what they'are supposed to 2
do, this is no problem.
L L
3 MR. ROBERTS:
The idea is people are doing what they l-4 are supposed to do, but it is not going to be looking at that 5
particular item.
6-CHAIRMAN SIESS:
It isn't really adequate.
7 MR. ROBERTS:
Not really, no.
That's why we're 8
saying this issue is going to have to be sent into the 9
prioritization process to be looked at.
10' MR. SZUKIEWICZ:
We have also identified some 11 subsequent issues that address this issue in part.
For 12 example, we assume certain failures of certain potential 13 common mode failures that could affect multiple systems and 14 could affect redundant systems such as loss of ventilation, 15 loss of air, certain power sources, which relate to this, and 16 it may be in prioritization that this may not, this may be a 17 low priority item conditioned on the resolution of these other i
l 18 specific items that we have, we will be talking about soon, i
)
i l
19 but right now, this is an issue to be prioritized.
20 (Slide) l 21 MR. ROBERTS:
The next issue that we identified is, 22 really two, consists two sub-issues, both related to failure 3
l 23 modes of digital ccmputer control systems.
()
24 The first issue, that there may be a potential for 1
1 25 adverse systems interactions between computerized control l
1 1
\\
HERITAGE REPORTING CORPORATION -- (202)628-4888 i
37 4-1 systems and' safety-related' protection systems, and the second 2
being that'the use of digial computer control systems for o
3
' safety-related purposes, perhaps in the future.
4 Against, we have the same general design criteria 5
that we had mentioned on the systems, the non-safety, 6
safety-related issue previous to this one,'but it appears here 7
that GIA 19, Generic Issue A-19 is going to be addressing the 8
use of digital computer control systems for safety-related 9
purposes, and also an ANSI standard has been developed that 10 will provide some guidance hopefully for addressing the issue 11 on Generic Issue A-19.
12 We are also making, also assuming here that the
()
13 potential for these systems interactions may be adequately 14 addressed, the first sub-issue may be adequately covered from 15 a regulation standpoint in General Design criteria 22 and 24, 16 so'the bottom line on this issue is that we are going to have 17 to do some confirmation and prioritization process to see if 18 these issues are covered adequately, essentially from Generic 19 Issue A-19 covering the second issue of digital computer 20 control systems for safety-related purposes.
1 21 DR. KERR:
How will you--I mean you don't I guess 1
22 take withi.. your province to determine when these things are 23 covered adequately?
That's someone else's job?
()
24 MR. ROBERTS:
That's right.
It wasn't our job to 25 make a judgment there.
We are just to identify a concern.
HERITAGE REPORTING CORPORATION -- (202)628-4888
38 1-DR. KERR:
Well, it was your job to collect those
()
\\/?
2 things that bear on the issue and someone looks.at them, says 3
this covers the issue or doesn't cover the issue.
m i
4 MR, SZUKIEWTCZ:
That is correct.
5 MR. ROBERTS:
That is correct.
6 MR. MICHELSON:
Is there a Generic Issue A-19?
7 15R. ROBERTS:
Yes, there is.
-8 MR. MICHELSON:
I thought the As were all USIs.
As 9
are generic issues, too?
Okay.
Thank you.
10 CHAIRMAN SIESS:
It is a hangover area.
You don't 11 use the As anymore, do you?
12 MR. MINNCRS:
No.
The A, B,
C, D was a
()
13 p'ioritization scheme that we had.
14 MR. MICHELSON:
It is part of hangover?
Some of the 15 generics should be called As.
16 (Slide) 17 MR. ROBERTS:
The next area, two scenar' s that had 18 been Section 7.3.5 of the report, both are somewhat related 19 because they were identified by NRC staff, issues that weren't 20 necessarily addressed in, as part of unresolved Safety Issue 21 A-47, the first concern being dealing with the SCRAM without a 22 turbine trip, including return to criticality resulting from 23 overcooling the primary system.
()
24 Currently it appears Generic Issue 144 is going to 25 be investigating this issue.
Consequently that issue is to be HERITAGE REPORTING CORPORATION -- (202)628-4888
39 1
prioritized.
2 (Slide) 3 MR., ROBERTS:
The second issue identified for, the 4
concern identified by the NRC staff was steam generator.
5 overfill leading to main steam line break, and a steam 6
generator tube rupture would involve the. blowdown of more than 7
one steam generator.
8 Currently there are, there have been three separate 9
unresolved issues that investigated steam generator tube 10 rupture--USI A-3, A-4 and A-5, and NUREG 0844 describes 11 integrated NRC program that has resolved these three issues.
12 With regard to steam generator and steam line 13 overfi13, Generic Issue 135 will address potential effects, 14-these potential effects on secondary systems components.
15 Therefore, it appears that the resolution of USIs.
16 A-3, A-4 and A-5 and Generic Issue 135 will address this 17 issue, but this is going to have to be confirmed by the I
18 prioritization process.
19 (Slide)
I 20 MR. ROBERTS:
The next issue is a specific case of I
21 the issue that I have already alluded to being systems 22 interactions, interactions between, resulting from multiple 23 f a'. lure also of non-safety related control systemt.
()
24 Here we have HVAC degradation or failure that could 25 cause multiple failures of non-safety-related control systems HERITAGE REPORTING CORPORATION -- (202)628-4888 a
40 T -~f
'l that could potentially impact the safety-related systems.
f~(f 2
Once again, General Design Criteria 24 requires, as 3
I have already said,.a single control system component failure 4
not' compromise a protection system, but it does not address 5
multiple control. system failures.
6 There are a number of standard review plan sections 7
that look at ventilation.
HVAC systems service safety-related 8
areas, but there aren't any real requirements or any guidance 9
as far as looking at HVAC system servicing non-safety related 10
' components, essentially control systems.
11 Therefore, it appears that potential degradation 12 effects not specifically addressed by the existing programs
()
13 are not enough to resolve this issue, so this issue is going 14 to have to be prioritized.
35 MR. MICHELSON:
One of the things that puzzled me a 16' little bit about this particular item is that there is no 17 mention made of the possibility that safety grade or 18 safety-related HVACs may also be potential sources of problems 19 for the safety-related equipment.
That was certainly talked 20 about at numerous Subcommittee meetings.
We didn't exclude 21 and say only non-service HVAC is a problem, yet it didn't seem 22 to get picked up in here unless I misunderstood the writing.
23 MR. ROBERTS:
That is something we hadn't drafted 1
()
24 the concern that way.
As we had read it, it was 25 non-safety-related systems.
HERITAGE REPORTING CORPORATION -- (202)628-4888
l 41 l
Er s 1
MR. MICHELSON:
The particular reference you gave l
(_)
2 was for an A-47 letter.where A-47 was dealing with non-safety, 3
but clearly the HVAC question applies equally to safety grade 4
HVAC as well as non-safety grade.
5 CHAIRMAN SIESS:
Doesn't it say that in the second 6
bullet?
7 MR. MICHELSON:
I'm not worried about the slide.
8 I'm looking at the document.
9 CHAIRMAN SIESS:
Standard review plan it says 10 provides guidance for design of HVAC systems for 11 safety-related components.
12 MR. MICHELSON:
As I said, I'm not concerned with
()
13 the slide.
I'm concerned with the report where they did not 14 include apparently unless you can point out to me you did 1
15 intend to include safety grade HVAC as well.-
I R16 MR, ROBERTS:
That wasn't included, but we can 17 include that.
18 MR. MICHELSON:
I would think that we ought to put 19 in a letter commenting on this report a paragraph dealing with 20 the fact that it should be.
i 21 CHAIRMAN SIESS:
Why would you mention it on the j
i 22 slide if you didn't--
23 MR. ROBERTS:
See, the bottom line, I mentioned it
(}
24 on the slide, because it was non-safety related HVAC that we 25 were making an issue of here, and we are saying that there HERITAGE REPORTING CORPORATION -- (202)628-4888
42
'{}
1 isn't anything there that is really looking at 2
non-safety-related HVAC.
The only things that, the only l
3 guidance you have is for safety-related systems.
We are not 4-addressing the concern her e that Dr. Michelson has brought up.
5 CHAIRMAN SIESS:
That guidance is not sufficient to
~
6 protect safety-related.
7 MR. ROBERTS:
That's not the issue we were looking 8
at here.
We.are not tryingto make'that claim.
9 MR. CASADA:
We have not seen that raised.
I mean 10 the guidance, the regulations and the reviews are clear on 11 safety-related support to safety-related systems, so that was l
12 wasn't picked up as a concern.
p,
(
13 MR. MICHELSON:
We had a long discusr, ion at one 14 meeting concerning the McGuire event which was safety-related 1
15 heating and ventilation as impact on the protection system.
16 Staff was present at these discussions, and it is in the 1
17 transcript.
It is in the minutes.
There it wasn't picked up 1'
18 here.
1 19 DR. KERR:
What is the issue, Carl?
l 20 MR. MICHELSON:
If you lose a safety-related heating.
21 and ventilating system, what would be potential interaction 22 effect on the loss of that system because inu are not talking 23 about solid state devices that start contributing?
()
24 DR. FERR:
If you are satisfied with the single 25 failure criteria, that takes care of it.
HERITAGE REPORTING CORPORATION -- (202)628-4888
L i
43 1
MR. MICHELSON:
This isn't the time to debate that.
2 CHAIRMAN SIESS:
I'm sorry.
This is the time.
They 3
are asking for our comments.
4 MR. MICHELSON:
Okay then.
5 MR. WYLIE:
I think this specific case Carl is 6
referring to, it was the degradation of both trains due to 7
elevated water temperature in the lake because the elevation i
B of the temperature in the control room caused the control 9
system to mis-operate.
10 MR. MICHELSON:
They are both located in the same 11 room side by side.
12 DR. KERR:
They simply weren't designed properly,
()
13 were they?
14 HR. WYLIE:
The whole cooling system had heated up.
15 CHAIRMAN SIESS:
There is nothing in the regulation.
16 MR. WYLIE:
Due to the environment.
17 CHAIRMAN SIESS:
See, there is an implication here, 18 and I'm not blaming anybody, that Standard Review Plan 9-4 19 provides guidance for safety-related syetems, that's adequate 20 for safety-related systems.
21 Now what I am hearing.is that design according to 22 that guidance is not necessarily adequate to prevent common 23 cause failures that could affect more than one service system.
()
24 DR. KERR:
Is the implication the McGuire system is 25 designed to satisfy SRB, et cetera?
HERITAGE REPORTING CORPORATION -- f202)628-4888
44
}.
l' MR, MURPHY: 'Did not--the r,ooling system exceeds ~the
'2 design envelope.
3 MR. MICHELSON:
It only got to 94 degrees., as a 4
matter of fact.
5-MR. MURPHY:
Had it stayed within the design 6
envelope, it met the criteria.
7 MR. MICHELSON:
No, no.
Design was 104 degrees.
8 MR. BAER:
As I recall the McGuire event, there was 9
another aspect that-hasn't been mentioned which was that 10 people did not look at temperature.
When they designed and 11 installed the cabinet,.they didn't look at temperatures or 12 estimate'the temperatures in the cabinets as opposed to the 13 ambient temperature in the room, and that was a contributor
'14 also at McGuire.
l:
l-15 MR. MICHELSON:
There is a more fundamental issue l
16 involved here which the McGuire only indicates how things can 17 happen.
18 The feedwater issue is, for instance, during a power 19 blackout, when you lose the heating and ventilating in certain 20 areas that have these control systems in them, how do the 21 control systems respond until such time as you can restore 22 ventilation?
And you may find you are getting multiple system l
23 responses from the failure of these systems during that time
()
24 that the temperature is elevated.
That's all I am saying is I
25 that you have to look at safety--
p HERITAGE. REPORTING CORPORATION -- (202)628-4888
45 1
MR. BAER:
Protection back to the control systam.
}
2 MR. MICHELSON:
I don't want to get into that.
I'm 3
just saying I think-there is an equal problem with safety 1
4 grade HVAC as well as with non-safety grade, and I think that 5
this issue just--
6 MR. SZUKIEWICZ:
We will go back and take a look at 7
it.
That's one point that we did not focus on.
8 MR. MICHR SON:
It certainly was discussed at the 9
meeting, and it's been well understood all along we are-1G worried about both safety grade and non-safety grade.
11 MR. BAER:
I. guess I am trying to make sure at least 12 I understand the concern as far as the safety grade system, so
(
13 could you go through it again just for the safety grade system 14 what the concern ought to be?
15 MR. MICHELSON:
The same context as all of these 16 other concerns; the point is, is there the possibility of 17 adverse systems interaction resulting from the loss of safety 18 grade heating and ventilating in a given area?
That's the 19 concern.
20 MR. BAER:
The answer is yes.
21 MR. MICHELSON:
The answer is yes, you have to look 22 at it, and it has to become considered for a possible generic 23 issue.
()
24 CHAIRMAN SIESS:
Next question is what is the 25 probability?
HERITAGE REPORTING CORPORATION -- (202)628-4888
46
,(
1.
MR. MICHELSON:
That's what do you, when do you 2
enter the generic issue decision-making?
The point is your l
3 draft copy doesn't make any mention of safety' grade.
It just' 4
talks about non, and that was my only point.
5.
MR. CASADA:
Okay.
6
' CHAIRMAN SIESS:
The standard review plan is 7
inadequate'in these examples.
Was it inadequacy of design 8
that followed the standard review plan, or was it a failure to 9
MSRP?
10 MR. ROBERTS:
As far as what issues?
As far as 11 safety grade?
12 MR. CASADA:
Talking about for the McGuire event?
13 CHAIRMAN SIESS:
Any event that somebody knows 14 about.
15 MR. CASADA:
I think we would have to get the 16 details of the specific events out and' compare them to the 17 requirements which I think is what Andy is going to want to 18 do.
19 MR. MIChELSON:
As I recall the Rancho Seco, the 20 last event was in part precipitated by.a loss of the 21 circulating fan in the cabinet.
Wasn't that correct?
That's 22 what started the instruments, blew the fuses.
23 I may be--but there is an event, rather elaborate
().
24 one, again in protection system where the ventilatinto fan for 25
-the cabinet went out and these things started to happen.
HERITAGE REPORTING CORPORATION -- (202)628-4888
7_-__-_-.
47 l'
I am saying again you have got to analyze these,
[
2
- that the ventilating system there wasn't safety grade, 3
safety-grade ventilation system on safe y-grade cabinet.
4 CHAIRMAN SIESS:
Gentlemen, I propose we take about 5
a ten-minute brer.h now.
6 (A brief recess was taken.)
7 CHAIRMAN SIESS:
Okay.
8-MR. MINNERS:
Before you start, in answer to your 9
question,.I talked to Tom King and he estimated approximately 10 a year to prioritize 20 issues.
11 MR. MICHELSON:
One year?
12 CHAIRMAN SIESS:
To prioritize 20 issues--that ain't
()
13 bad.
14 MR. MICHELSON:
It won't be 20 issues, will it?
You 15 are going to try to group this to some extent?-
16 MR. MINNERS:
That's part of the prioritization 17 process.
18 MR. MICHELSON:
These 20 issues.
19 MR. MINNERS:
If we give them the 20 items, it will 20 take a year to p:rioritize them.
21 CHAIR'.4AN SIESS:
Right now there are 21.
22 MR. SZUKIEWICZ:
Already existing.
23
! Slide)
()
24 MR. ROBERTS:
This next issue we are going to 25 describe somewhat parallels the previous issue with HERITAGE REPORTING CORPORATION -- (202)628-4888
L 48 i
degradation.of'HVAC failures.
1 I
2 However, this one' deals with the effects of.
'3' electrical system degradation, in essence undervoltage and
~
4 overvoltages may not have been adequately evaluated.
5 There-appear to be a number of generic design 6
criteria and standard review plan sections that provide L7-guidance for addressing electrical system failures.
8.
However, it turns out that most of the regulations 9
are geared toward looking at complete loss of electrical 10 systems rather than looking at overvoltages or undervoltages, 11 and there have been, for example,_there has been1an 12 information notice 8916 that has described the potential for
();
'13 an undervoltage event in plants, DC' power system, that could 14 lead to total loss of AC power, but on the whole, the 15 regulations themselves are only addressing loss of power for l
16 the most part, r
17 Therefore, we feel that this particular issue is not 18 specifically addressed by the regulations or any existing 19 programs, and therefore, it needs to be prioritized.
20 (Slide) 21 MR. ROBERTS:
Analogous to the issue of electrical 22 systems, degraded electrical system, is degraded compressed 23 air system concerns.
Similarly, the effects of air system l
1 i
24 degradation, gradual loss of air pressure, underpressurization
{}
25 and overpressurization, may not have been adequately
.HERTTAGE REPORTING CORPORATION -- (202)628-4888
49
(}
1 evaluated.
2 There are standard review plan, there is a standard 3
review plan section that addresses designer compressed air 4
systems, and there are reg guides that designs total, looks 5
at, addresses total loss of air pressure both sudden and 6
gradual.
Originally there was a generic issue, Generic Tssue 7
43, that was supposed to look at reliability of air systems.
8 It provided the limited evaluation of gradual loss of air 9
pressure, and underpressurization.
However, it has been 10 suggested that degradation of air systems be prioritized 11 separately.
12 And in fact the Generic Issue 43, Generic Letter GL 13 88-14 only addressed total loss of air system pressure.
There 14 have been several events that may have prompted the NRC to 15 issue information notices that have described events that have 16 led to failure of components as a result of degraded air 17 system pressures.
18 Information Notice 80-40, 88-13, and on the next 19 slide, 82-25, all describe events of this nature.
There has 20 also been a NUREG that has been issued that has tried to look 21 at operating experience related to air system problems.
22 Status on this issue--while Generic Letter 88-14 23 addresses total loss of air system pressure, the
()
24 overpressurization, gradual loss of air system pressure is not 25 addressed apparently in the regulations or by existing HERTTAGE REPORTING CORPORATION -- (202)628-4888
.I
- 1 50
{}.
1-programs.-
Therefore, this issue.needs to be prioritized.
.s 2
(Slide) 3 MR. ROBERTS:
The next issue is a rather broad one, i
4 looks at effects of a components failure or inadvertent 5
actuation at an unanticipated time which may not have been-l 6
adequately considered.
7 Untimely component operation could disable the 8
safety system, for example, inadvertent or unanticipated 9.
. actuation of valves having potential for transferring 10-safety-related suction to an empty sump--that's just an 11 example.
It is not meant to embody what that issue is all 12 about.
(
13 MR. MICHELSON:
Let me give you an example of one 14 that you do need to be sure is included in the generic issue 15 consideration, and that is the case of the residual heat-16 removal system for boiling water reactors.
17 If you are in the process of trying to cool the l
18 suppression chamber in some post-accident period and you 19 should lose power to the particular system, the fact is you 20 may lose power to both systems.
If this is caused by some 21 switchyard event, you lose power to the systems, the discharge 22 valve to the suppression chamber doesn't close, it has no 23 power to close.
The pump trips, and the system drains its
()
24 water into the suppression chamber.
25 Now that inactivated the system until you can get HERITAGE REPORTING CORPORATION -- (202)628-4888
h 51 1
'1' Lvalves closed'again, later refill the system with water, clear
'1
)
2 it up; vent it and so forth,'before'you can even restart it.
3 That's the kind of an untimely problem I think we are talking i
4 about in this particular issue, so that one as an example 5
ought to be looked at.
L 6
MR. BAER:. Is this a situation where it drains from 7
8-MR. MICHELSON:
The problem is the heat exchangers 9
way up--in the air, it drains from the discharge of the heat 10 exchanges on down.
It is a hundred feet of elevation, so it 11 dumps the pipe in a matter of less than a minute because you 12 have no problem venting the system because you probably
()
13 drained the suppression chamber at the same time that provides
~
.14 the air vent for it.
It would drain anyway.
15 HR.' MURPHY:
In the review of operating experience, 16 we mention a couple of those kind of events.
17 MR. MICHELSON:
We have had a couple of operating 18 events where people didn't close the discharge valve before 19 they tripped the pump.
They said we refilled it and we are 20 okay.
That's true if it occurs by itself, but if it occurs 21 during an accident in which you have lost off-site power, and 22 that system trips out, and chances are loss of off-site power 23 isn't lost in time zero.
It is lost maybe a minute later,
.( }
24 that at the time the pumps are n1 ready up and running, the 25 valves are open, it is churning away, potentially.
l L_________ _"
f Y_F
- ~~__S -
~
52 e
- l(}.
1
,HR. BAER:
There has been some events where they
'A.
2 have.actually drained the reactor or drained the reactor-
.3 vessel.
4 MR. MICHELSON:
That's a little different situation.-
5 You drain it back into the suppression chamber.
6
-MR.
BAER:
Is that part of your concern?
L 7
MR. MICHELSON:
No.
I'm just giving you one 8
example.
I don't want to clutter other things, Just a simple 9
example of cooling the torus.
If you trip the pumps without l
10 closing the valve, you will drain the pipe.
Look at the 11 geometry and it becomes immediately self-evident.
It has 12 never been accounted for in the design of these things.
They
()
13 are a worry at the time.
That's the reason it didn't start'up 14 the RHR system.
Because the valves had been cycling, it 15 drained the pipe.
16 MR. BAER:
What is the problem if.you drain the--
17 MR, MICHELSON:
Can't restart the pucps on an empty 18 pipe.
You tear them right off the supports, or at least 19 that's the danger.
You don't know what is going to happen if 20 you try to start them on an empty pipe.
Supports really 21 aren't designed to accelerate the water through that system.
22 MR. ROBERTS:
There are general design criteria that j
23 establish minimum requirements for design components.
j
()
24 However, general design criteria aren't specific enough to be 25 telling the licensees to be looking ac these types of HERITAGE REPORTING CORPORATION -- (202)628-4888
(
53:
' j
.'1 incidents.
2 The lessons learned program should identify generic 3
problems in this area through NRC review of Leks and through 4
the utility operating c~perience reviews which require the
-5 result of post-TMI requirements.
6 However, failure analyses-tend to assume either
-7 w rking or failed conditions that do not address all P
8 tim?-ordered sequences during.which failure or inadvertent 9
actuation may occur.
There is, this paiNicular' issue is to be 10 prioritized.
11 (Slide) 12 MR. ROBERTS:
The next issue is harsh environments I
13 may propagate by some unknown or unrecognized pathway into 14 another zone.
15 By harsh environments, here we mean harsh 16 environments that are a result of some design basis event.
17 Therefore, these potential propagating to other, by 18 propagating to other zones, there is potential for impacting 19 redundant trains of safety-related components.
20 There are equipment qualifications rules that you 21 must follow in order to assure your safety-related equipment 22 is qualified for these harsh environments; 10 CFR 50.49, QM 23 50.49, standard review plan Section 3.11, Reg Guide 1.89, IEEE
'( )
24 Standard 323 all provide the guidance for qualifying equipment 25 important to safety for potential harsh environments.
HERITAGE REPORTING CORPORATION -- (202)628-4888
54 1
MR. MICHELSON:
That's potentially harsh 2
environments caused by so-called design basis accidents only?
3.
MR. ROBERTS:
That is correct.
4 MR. MICHELSON:
Outside of containment, there are
'5
.very.few harsh environment areas.
Most of.the equipment 6
.outside of containment that might be involved in flooding 7
events and things of this sort simply aren't qualified for it 8
because they are not considered harsh ' environments because 9
that was kind of part of Chapter 15 evaluation.
10 MR., ROBERTS:
I recognize that.
This issue is 11 specific to design basis events, and other types of events 12 that aren't design basis events are going to be described.3n
( ).
13 subsequent issues.
14 MR. MIrHELSON:
I guess what I'm trying to say is 15 you are making the issue specific to design basis events, and 16 the ACRS concerns were with non-design basis events, and that l
l 17 didn't seem to come through real well.
l l
18 MR. SZUKIEWICZ:
The other non-design basis events.
19 are addressed in the other specific issues.
20 MR. MICHELSON:
They are scattered around 21 admittedly, but this is, this is, this is an issue, 22 propagation of harsh environments, and you are meaning only 23 inside of containment.
That's one thing, and we think we are 1
()
24 hopefully in pretty good shape there anyway.
It is outside of 25 containment where we haven't designed for harsh environments l
HERITAGE REPORTING CORPORATION -- (202)628-4888
55
{
1 but can get them from fires, floods,-whatever, and those kind 2
of harsh environments--I wouldn't even want to call them 3 ~
harsh--that has a special connotation, some other use.
4 MR. CASADA:
That's exactly--
5 MR. MICHELSON:
Could change the word even.
6 MR. CASADA:
When we get the-whole list, we can l'ok o
7 at back at this.
I would like to look back at this because I 8
think we have got all the elements you talked about in some of 9
these others, and that way we can reserve this as harsh.
10 MR. MICHELSON:
See, one of the issues is the.HVAC 11 system.
It is a fine conduit for adverse environments being 12 moved around the plant, and is that going to be covered then
)'
13 under HVAC?
14.
Well, if it is, there is no words-there.
It is not
.15 mentioned over here in this section, and so where is it going 16 to be mentioned?
You know, if you are trying to gather l
l 17 together the concerns, the HVAC system is'one of the concerns.
18 The electrical conduit system is another concern.
Water 1
i 19 getting in one box seems to be very nicely conducted right j
20 into the guts of the other boxes where there isn't any 21 qualification for 4ater, and those kinds of things I'm not 22 sure come through unless this is, this is worded a little 23 differently because I don't believe we are arguing the concern
()
24 I think because I'm just pointing out lets get it all down in 25 k-"iting somewhere.
HERITAGE REPORTING CORPORATION -- (202)628-4888 1
56 1-CHAIRMAN SIESS: -Let's look at the next item which'I
}
2 don't understand.
.3 MR. MICHELSON:
Yes.
It's--we' sorted.these out into 4
smaller compartments, but many of these_ items are related to 5-several of these compartments, several of these questions.
3 6
CHAIRMAN SIESS:
The question that.comes to my mind l
7 is what kind of harsh environment are you. talking about in the 8
preceding one?
9-MR. ROBERTS:
Preceding one is design basis event, 1
1 fl0 specific design basis event.
11.
CHAIRMAN SIESS:
By design basis event, you mean 12 pipe break or something?
).
13 MR. ROBERTS:
Loss of coolant accident;. main steam.
14 line breaks.
15 MR. MICHEL3ON:
Not pipe break outside in the 16
. auxiliary building, for example, which are not design basis 17 events.
18 MR. ROBERTS:
That's right.
19 MR. MICHELSON:
Unless they are main steam 20 feedwater.
21 MR. SZUKIEWICZ:
That's a different issue.
12 2 MR. MICHELSON:
Eleven is devoted to fire.
Look 23-somewhere between 10 and 11, there was also this other set of
()
24 equipment exposed to non-harsh, normally non-harsh 25 environments, but I do some, some adverse effects from such HERITAGE REPORTING CORPORATION -- (202)628-4888
.[ -
57 1
things as pipe break, and that sort of. thing out there.
2 MR. SZUKIEWICZ:
What we tried to do is--
3 MR. MICHELSON:
Doesn't seem to be covered.
4 MR. SZUKIEWICZ:
What we tried to do is separate 5
them so we can focus on specific issues because we make them 6
general again, and it almost goes back to system interaction.
7 between type of concern.
8 MR. MICHELSON:
We sure somewhere have'to mention 9-it.
It has got to fit in one of the compartments.
I don't 10 object to the arrangement here at all.
I'm just saying that 11 it doesn't seem to fall, be covered by any of your 12 arrangement.
13 CHAIRMAN SIESS:
Guess I'm still a little confused.
14 Going back to the harsh environment say due to LOCA, this 15 would be a physical impact?
It would be a high temperature?
16 It would be water or steam, right?
17 MR. CASADA:
Right.
18' MR. SZUKIEWICZ:
It could be radiation.
19 CHAIRMAN SIESS:
For the des!.gn basis accident?
20 MR. SZUKIEWICZ:
Right 21 CHAIRMAN SIESS:
Now Carl, you are talking about 22 something beyond the design basis?
23 MR. MICHELSON:
No.
I'm talking--we don't get the
()
24 design basis pipe breaks out in the auxiliary building, for 25 instance.
They are not covered by Chapter 13.
They are HERITAGE REPORTING CORPORATION -- (202)628-4888
58
-f]
1.
covered by a special, special letter a long time ago that v-2 says.look at them.
3' CHAIRMAN SIESS:
You are saying.a pipe break?
4 MR. BAER:
That's in the SRP.
5 MR. MICHELSON:
Yes, but it isn't in this document.
6 CHAIRMAN'SIESS:
You are saying a pipe break in the 7
auxiliary building is not postulated for, qualifying equipment?
8 MR. MICHELSON:
That's right..It'is'not.
You only.
9 have to qualify for harsh, harsh environment, which is only 11 0
-high energy' pipes.
That's not water pipes.
Steam line to 11 RCIC turbine is covered.
Steam line to HPCI main feedwater 12 main steam, that's abou' it.
(
13 CHAIRMAN SIESS:
So give me an example.
14 MR. MICHELSON:
Cooling water pipe breaks, flange 15 rupture.
16 CHAIRMAN SIESS:
Doesn*t that come under the heading 17 Hof flooding?
18 MR. MICHELSON:
Yes, somewhere else, but not 1
19 flooding for fire which is--
1 l
20 CHAIRMAN SIESS:
I am looking at harsh environments 21 and factor 10.
22 MR. MICHELSON:
They seem, though, to be talking l
23 about harsh environments created by the design basis events.
j 1()
24 CHAIRMAN SIESS:
Design basis event in the auxiliary 25 building is high energy line breaks.
p i
HERITAGE REPORTING CORPORATION -- (202)628-4888'
]
59 p'
~ MR.. MICHELSON:
No, not by definition, that's not.
'1' 2
CHAIRMAN SIESS:
High energy line breaks outside of 3
. containment?
4 MR. MICHELSON:
Pardon me--high energy,.yes.
5 CHAIRMAN SIESS:
If it is not high energy, you said.'
6 it is just water?
7 MR. MICHELSON:
If it'is not high energy, it is not 8
covered as design basis event.
9 CHAIRMAN SIESS:
Wouldn't that be flooding?
10 MR. MICHELSON:
That would have to be under 11 flooding, correct.
12 MR. SZUKIEWICZ:
And it is addressed in other areas.
(
13 CHAIRMAN SI3SS:
I'm trying to find out what is 14 left.
15 MR MICHELSON:
Where do you think it is addressed?
16 Maybe that would clear it up.
Because 11 is for fire and we 17 don't, we don't count that one.
t 18 MR. WYLIE:
I assume some of it is in seismic.
I 19 MR. CASADA:
Fifteen--it is page 24.
20 MR. MICHELSON:
When we get to it, then you can 21 peint it out.
E22 MR. CASADA.
The point on the harsh environments was 23 there is a procedure now for the design basis events that they
()
'24 define the environment, the zone that that affects, and the 25 point is that the concern was raised that you define a zone HERITAGE' REPORTING CORPORATION -- (202)628-4888
60' 1
this large, but in fact there is a drain or some communication a
2 like HVAC to another area, so that other area should have been 3
qualified as well.
Just.that very small part of it is what 4
this is talking about, and in a minute we will get on to 5
talking about the other kinds of pipe breaks and things that i
6 can cause flooding, and they have zones of their own, but they I
7 aren't formal like these are.
8 MR. MICHELSON:
They also have the same problem.
9 MR. CASADA:
Exactly.
10 MR. MICHELSON:
Why don't you at least retitle 7310 11.
to add'the words from the design basis events?
Then the title 12 at least kind of flags immediately to the narrowness of the
()
13 particular issue.
14 MR. CASADA:
We used harsh to indicate that, but you 15 are right.
You have to know that definition.
You have to 16 know that definition.
17 CHAIRMAN SIESS:
Put harsh in quotes.
18 MR. CASADA:
Okay.
19 MR. MICHELSON:
Add design basis events; by 20 definition it covers everything of concern.
Now you will 21 think about HVAC as a possible conduit although we haven't 22 very many examples.
There are a few for the high energy 23 breaks outside.
That has been a concern.
(}
24 MR. ROBERTS:
The next issue we are looking at here 25 dealt with multiple trains of safety-related equipment being HERITAGE REPORTING CORPORATION -- (202)628-4888
L 61 1
affected by heat, smoke and water propagation effects 2
resulting from fires.
3 There are a number of generic design criteria and 4
regulations that establish requirements for protecting l
'S redundant trains of equipment required to achieve plant L
f shutdown and for establishing fire protectior. planning.
l 7
In addition, there are sections in the Standard
[
8 Review Plan that specify the safety-related equipment should l
9.
Ebe protectedfrom the effects of fire, heat, smoke, and water-1 l
10 exposure.
From that' standpoint, it appears the issue is being 11 addressed' generally in the regulations'and guidance.
12 However, we are relying on the licensee evaluation'
()
13 of the propagation pathways to ensure adequate protection.
14 Therefor e, we believe this issue probably needs to be 15 prioritized.
l 16 CHAIRMAN SIESS:
Now the regulations permit 17 cometime.? simply separation for fire?
18 MR. ROBERTS:
That is correct.
But there is, there
-1 19 are requirements for protecting against things like 20 inadvertent actuations of fire suppression systems.
21 CHAIRMAN SIESS:
Separation doesn't do much for 22 smoke or water, does it?
23 MR. ROBERTS:
Not unless you adequately define your
()
24 zones.
25 CHAIRMAN SIESS:
Isn't this an item that is included j
JRITAGE REPORTING CORPORATION -- (2J2)628-4888
)
[
62 1
1.
L 1
for fire risk scoping studies, Carl?
l 2
MR. MICHELSON:
Yes.
I think we will hit it there, L
0 and whatever results from a letter that we hopefully will 4
write on fire ought to be picked up in this section if it 5
changes anything.
I don't know that it will change anything, 6
but it might.
I 7
CHAIRMAN SIESS:
I know somewhere else that 8
reference is'made to the fire risk scoping study.
At least I 9
thought I saw it.
10 MR. CASADA:
It is discussed in the report.
It 11 doesn't show up on the slide, but it is discussed in the 12 report.
( ()
13 MR. MICHELSON:
We will be writing a comment letter 14 on the scoping study.
15 MR. CASADA:
That's this afternoon's discussion?
16 MR. MICHELSON:
"Je'll write the letter this week 17 hopefully.
18 MR. SZUKIEWICZ:
This week?
19 MR. MICHELSDH:
Yes, I hope.
I notice on page 94, 20 something puzzled me, and maybe it is just a wording problem.
21 It is in section 73114.
22 CHAIRMAN SIESS:
You are in the report now?
23 MR. MICHELSON:
Yes, page 94.
It says fire is going
(}
24 to especially interact with systems and components by creating 25 a harsh environment from smoke and water because of the high j
"ERI m E REr R m Rr RA N -- <202>e28-4888
63
.(.
1 melting point, i.e.,
damage threshold of metals, valve and 2
pump damage is of little concern during the fire.
3 That's kind of a misleading statement because I'll 4
admit maybe the valve body isn't going to melt.
Certainly the 5
motor is going to be susceptible to damage before the valve 6
body is of concern.
This kind of pumps and. valves are not a 7.
problem, and yes, they are--it is the motor.
8 MR. ROBERTS:
I don't think we meant to say they are 9
not a problem.
We are saying they are not a problem from 10 direct heat impact, below that, just below that.
11 MR. MICHELSON:
It is the motor that is the problem.
12 MR. ROBERTS:
Two sentences down we say the damage 13 to--
14 MR. MICHEhSON:
tow you are talking about electrical 15 cables and components.
If you make sure the reader realizes 16 you mean the pump motor and the valve motor, fine.
17 MR. CASADA:
I could do without that sentence as 18 well.
We say what needs to be said further on.
19 MR. MICHEL5ON:
Do something on it.
We do have 20 to--i t is the motors that you worry about and the electrical 21 cabling to the motor.
22 MR. SZUKIEWICZ:
That was the intent.
We can modify 23 it.
()
24 MR. MICHELSON:
Okay.
That was the only really 25 comment I had on that subject.
HERITAGE REPORTING CORPORATION -- (202)628-4888
64
~1 MR. ROBERTS:
As an additional comment, I would like UJ 2
to say that what we have presented in here and what is in that 3
report represents a snapshot of the regulations'or letters 4
that had been issued on various items through the fire risk 5
scoping study.
Some of that is not in here.
If there are 6
stick areas in which come more documentation has been issued, 7
.that we don't appear to mention, mention in the document'or 8
here, we would like to know about it.
9 (Slide) 10 MR. ROBERTS:
The next issue that we got into dealt 11 was synergistic effect of harsh environmental conditions that 12 mayinot have been adequately addressed by the licensees.
( )'
13' General Design Criteria 4 and 10 CFR 50-49 do 14 establish the requirements for environmental qualification of' 15 equipment and specifically include the consideration of 16 synergistic effects.
17 In addition, the Standard Review Plan, rett guides, 18 and IEEE 323, NUREG 0588 all provide guidance for corducting 19 environmental qualification.
They reqcit e that any identified 20 synergisti' effects vust be included in the analysis.
21 However, there is no real guidance provided for how 22-these synergistic effects should be analyzed.
Sandia National lf i
23 Lab over the years has issued a number of reports that have I
(}
24 been investigating, trying to describe efforts to study the 25 effect of environmental synergisms on various materials and HERITAGE REPORTING CORPORATION -- (202)628-4888
E 65 1
components.
lI 2
The regulations, therefore, appear to require that 3
these synergistic effects be considered and addressed'whenever 4
possible during testing.
However, there appears to be very p
5-little guidance available'for. performing such analyses'or 6
- testsc, 7
Therefore, this issue we feel needs to be
'8
-prioritized.
9 CHAIRMAN SIESS:
What is an example of a synergistic 10 effect?
11 MR.. ROBERTS:
A synergistic effect would be defined 12 as the sum where the effects of independent, the independent,
()
13 the overall--
14 CHAIRMAN SIESS:
I know what it means.
Give me two 15 things.
16 MR. CASADA:
Age, and then doing radiation tests as 17 opposed to accumulating radiation over a 30-year lifetime like 18 a component actually would.
19 When we do that in the laboratory, we artificially 20 age, and then we radiate in the short time, and it may be., you 21 know, someone would postulate that yes, but in fact if.that 22_
damage is over time,.there might be other effects than what.we 23 see in the lab, and you can take any two and combine them like
()
24 that and they may or may not exist, the problems that people 25 postulate, but that's what this is about.
J
66 1
.MR.
SZUKIEWICZ:
In some cases, vibration at the
- q 2
same time you have elevated temperatures may be more of a 3
concern _than. testing them separate.
4.
(Slide) 5 MR. ROBERTS:
The next issue dealt with potential 6-detrimental effects of the harsh environmental conditions on 7
-subcomponents of mechanical equipment, specifically seals, 8
gaskets,. packing, lubricating fluids.
9 Once again, Generic Design Criteria 4 gives general 10 guidance or general requirements for environmental-11 qualification of' equipment.
12 Standard Review Plans, IEEE Standard 323, NUREG 0588
()
13 all provide guidance for conducting environmental 14
-qualification.
15 There have been a number of information notices that 16 the NRC has issued over the years that have reported events 17 that have involved failure also of these types of components.
18 However, in the past, the eq'aipment qualification has 13 concentrated on electrical equipment.
Mechanical equipment 20 without electrical components has received much'less a
21
. attention.
{
22 We believe this issue needs to be prioritized.
I 23 CHAIRMAN SIESS:
There certainly have been a lot of 1
.( )
24 instances reported of seals, gaskets and packing failing.
1 L
25 Every time you picked up a morning report, somebody got a leak I
HERITAGE REPORTING CORPORATION -- (202)628-4888 l
a-67 i
1 in a seal seal or a gasket.
2 Are those environmentally related, or just 3
everything is environmentally related?
4 MR. ROBERTS:
I guess in a sense.
The environment, 5
whatever environment a component is going to be working in, 6
you are assuming that your subcomponents are. qualified to 7
operate in that-environment, so you can think of, for example, 8
you know whatever environment the component is set in is the 9
environment of interest.
It breaks down, it has something to i
i l
10 do with the environment or its operational restraints as far l'
11 as operations.
L 12 CHAIRMAN SIESS:
Environmental qualification doesn't'
()
13 necessarily mean harsh.
14 MR. ROBERTS:
No, not at all.
1' 15 CHAIRMAN SIESS:
If you left environmental out 16 there., would it still cover an awfull lot of things that 17 happenod?
18 MR. ROBERTS:
Yes, but I know I have a hard time.
1 19 Depends on how you want to define environment.
I am, we are 1
20-not really talking about--we are all sitting here in the-21 environment.
I guess I wouldn't have a problem with taking it 22 out.
23 CHAIRMAN SIESS:
I am just trying to understand the
(])
24 issue because I'm sure that seals, gaskets and packing fail l
25 regularly.
I don't know what the people do to prevent it, l
i HERITAGE REPORTING CORPORATION -- (202)628-4888
68 I
whether.they have a replacement schedule that is accelerated 2
or something, but--
3 MR. CASADA:
This issue' grew out of people saying 4
well, qualification, we have done a good job on electrical.
5 How aboat mechanical?
Specifically they are concerned with--
6 that's how it grew.
You are talking more a reliability of 7
seals, gaskets, packing kind of issue, which is different than 8
the flavor this has now.
9 MR. ROBERTS:
I guess these really are more--
10 CHAIRMAN SIESS:
We have got a lot of data on this 11 reliability.
Do we have any feel for abnormal environments?.
12 I mean let's face it.
The environments, a lot of them are.a
()
13 little different from this room.
It is hot.
Sometimes it is 14 wet.
And we know this is a problem.
This is--somebody said 15 should we have looked at this?
16 MR. CASADA:
I don't know, if you take the operating j
17 experience problems that have happened with these type of 18 components, I don't kr^w what fraction of those you would 19 consider environmentally related.
I don't know that.
I think
)
l 20 that's one of the things at you need to do in looking at j
21-this further.
22-The other question you asked, the reliability is a 23 little larger than this issue is envisioned at the moment.
()
24 MR. THATCHER:
I think--Dale Thatcher.
I think on 25 the reactor coolant pump seal issue that's a separate generic l
i HERITAGE REPORTING CORPORATION -- (202)628-4888
69-1 issue.- We are looking a't a number of normal operation d.
2-problems with the seals, and we have found that--I don't know 3
.what the number are--certain percentage comes from potential 4
' environmental things, but a large !. amber come from maintenance 5
problems and a whole list.
6~
CHAIRMAN SIESS:
Just had two plants tear up the 7-seals.
8 1MR.- THATCHER:
Yes.
I guess my question, Myron, 9
before we used the word harsh, or it was implied that the word
~
10 harsh was used, that we were dealing.with design basis events.
11' Was that the intention here also?
12 MR. CASADA:
No.
I'm thinking about that, too.
i()
13 Calling it environmental qualification makes people like me 14
'think about design basis events and maybe that's not the 15 right, the right scope to have on this issue, because the 16 design basis events, these kind of corponents are your least l
17 problem unless it is like a--Dale, do we know if the original 18 concern was raised?
19 MR. ROBERTS:
Original concern grew out of 20 qualification, general qualification, equipment qualification
.21 from mechanical equipment, and not--at this time I don't-22 recall whether it was from a design basis event standpoint.
23 MR. CASADA:
Unless somebody here knows, I.would
'( )
24 have to look.
1 25 MR. MICHELSON:
Example of equipment qualification
{_- _ _ _ --
nERI m E REr Rr m Re RA m n -- (202>628-4888
70
. fq 1
question related to the' environment--in the case of air
'}
+
2 handling units 1for heating and ventilating areas of the plant, 3
these are normally designed and sized for a certain relative 4
humidity and so forth that.
Set the load on the motor, that 5
the motor is a pump, of course, 6
Now as the humidity or the water content _of the air 7'
increases, the load on the motor increases, and in the case of 8
a very severe environment, if it is only a short duration, you 9
may be-burning up the motor on the fan trying to pump 10 literally water through it or water droplets in high 11 concentrations, so you have, do have to consider the harsh 12 environment on, the effects on the equipment, and you have to,
()
13 if you are trying to take credit for that equipment in the 14 post-accident situation, you have to be sure that that even 35 momentary harsh environment does not destroy the capability of 16 the equipment. so at least air handling unito, it is a very l
17 important question.
What in the environment you are trying to j
l 18 get for a pump of a particular kind?
.19 CHAIRMAN SIESS:
Wouldn't that be a design f
20 requirement?
21 MR, MICHELSON.
No, unfortunately not.
There is no 22 design requirement for these unusual environment scenarios 23 outside of containment.
24 DR. KERR:
Fans are not required to pump water?
.( }
25 HR. MICHELSON:
No, indeed they won't.
t HERITAGE REPORTING CORPORATION -- (202)628-4888
_q,. :
f3 i
f
- 71 1
CHAIRMAN SIESS:
He said outside containment.
2 M R '..MICHELSON:
That's what I am talking about.
3 Inside of containment, you sacrifice them or you take'it into 4
account.
5
_DR.
KERR:
Do you think they should be. designed to
-6 pump water?
7 MR '. MICHELSON:
No.
I am not saying that.
I am 8
saying.you have to consider this in doing these studieszand i i i
.dec d ng whether or not if you are taking cred t for the 9
10 equipment,.yes, it has got to be designed for whatever the 11 environment is that_you expect the equipment to survive, and 12 so you have to identify the environment, and then look at
-( [
13 these various' components.
14 CHAIRMAN SIESS:
This harsh environment is a high 15 energy pipe break?
16 MR. MICHELSON:
May be low energy.
I can take hot-17 water, 200 degrees overload in that. fan air handling unit with 18 no trouble at all.
If it hasn't been--
19 MR. BAER:
It seems to me that we are oscillating 20 between two issues. 'The mechanical people tend to talk about 21-just qualification of mechanical' equipment, which--and since.I 22 know the Committee has addressed a 1st of concern about this 23 reliability in general, and there are a lot of mechanical 24 components that have never been quote, qualified in the normal
}
25 sense--snubbers are one thing that people are moving in that HERITAGE REPORTING CORPORATICi -- (202)628-4888
f 1
72
{}
1
. direction now. 'And that's sort of one issue.
2 And the other issue is you know, the question of the 3
environment, unusual environmental conditions which you just 4
brought up, Carl, and I guess maybe we are looking for some 5
guidance as to whether you think they ought to be like two 6
separate issues or combined or just focus on one or the other, 7
MR. MICHELSON:
My comment was only relating to-1 L
8 whether or not'we identified this as part of.the issue or l
9 identified it as another issue or put it somewhere, but where 10 is the consideration of the change in the environment on the 11 loading of the equipment?.And not just on whether the hhat is 12 affecting the mechanical aspect, electrical and mechanical, I
13 because the motor is going to burn up.
The equipment is not
(
14 likely to be unduly stressed.
It-is the motor or the belting 15 on it or whatever.
In many cases, air handling units are belt 16 driven.
What is this unusual environment going to do to the 17 belt drive?
I think it has to be considered.
I 18 If you are really doing a systems interaction study 19 on whien the initiating event causes something t'.* happen that 20 changes the environment for these air handling units, you have 21 got to now say how do they behave in that environment?
I hope 22 we would ask that question, or we haven't really done a 23 systems interaction study.
These are, these unusual and
()'
24 unanticipated things, I thought you were talking about 25 originally and adverse systems interaction.
Generally that is l
l HERITAGE REPORTING CORPORATION -- (202)628-4888
73 L-(
1 unanticipated because people don't think about it.
It
}-
2 certainly can be easily said to be anticipated if you'think 3
about it, so somewhere-I assume--but I don't find it, and I 4
wonder where it is.
5 Mk. SZUKIEWICZ:
Wasn't this issue primarily going 6
to focus on mechanical equipment that wasn't environmentally 7
qualified by test and we were, this was going to go back and 8
take a look and see how things like gaskets, seals, packing 9
ar.d lubrication were addressed and that would be, that was the 10 limit of this particular issue?
11 MR. ROBERTS:
That is correct.
12 MR. SZUKIEWICZ:
That's all.
13 MR. MICHELSON:
Personally I think it's good limits 14 if we try to identify then another issue.
15 MR. SZUKIEWICZ:
Although I think that here we are 16 saying harsh environment, and I think we have need to make it 17 clear that this is not just limited to a design basis event, 18 but to any abnormal elevated temperature, pressure, whatever.
19 MR. MICHELSON:
Use that word harsh.
20 CHAIRMAN SIESS:
What Carl is saying is in 21 considering malfunctions or failures, I guess the scope of 22 probabilities, you are not putting any limits on it.
High 23 energy pipe breaks we don't.
We say they can happen, so let's
()
24 assume, assume a malfuncron or failure.
Consider the 25 environment that results from that malfuncton or failure.
l HERITAGE REPORTING CORPORATION -- (202)628-4888
74 1
. Consider the effects of that environment on anything that's.
2 needed to mitigate the consequences of that malfuncton or 3
failure. ~Now if there are consequences to mitigate you don't-4 care but.you have got to trace through the thing and see if i
5-after it happens, the other things that you want to-happen 6
will do it.
That's the whole issue of environmental 7
qualification.
8 MR. MICHELSON:
Yes.
That's why'we environmentally 9
qualify some things, because we find that we need them and 10 they wouldn't normally be able to withstand the environment.
11 MR. SZUKIEWICZ:- We weren't going to go back and 12 re-evaluate the adequacy of all of the environmental
)
13 qualification process.
14 MR. MICHELSON:
We are trying to identify subtle 15 possibilities that you keep alluding to in the original 16 definition of systems interaction.
I am just saying here is
.17 one of the subtle ones that need to be flagged'somewhere.
18 MR. SZUKIEWICZ:
But for example, in the air 19 handling system, we are not going to go back and look at the 20 mechanics or mechanic failure.
We are just going to say ne 21 have already looked at total losses, and the only thing that 22 we didn't look at which we say that we will look at would be 23 partial losses.
()
24 Now it would be independent of how these losses 25 could occur, whether it could be because of an environmental HERITAGE REPORTING CORPORATION -- (202)628-4888
75 1
condition, or whatever.
The only thing that we would-look at cm s
2 specifically--
p 3
CHAIRMAN SIESS:
Is that true?
4 MR. MICHELSON:
I don't think so.
5 CHAIRMAN SIESS:
Is that true?
You see, you 6-postulate a loss, period, without any reason for it, but now-7 the reason for that loss, if it is reason A, it might be a-8 different consequence of that loss than if it is reason B.
9 MR. SZUKIEWICZ:
If you if look at all possible--
10 CHAIRMAN SIESS:
You be sure that losing a 11 particular. system, no matter what caused it, is all right.
12 MR., SZUKIEWICZ:
But we basically did loo.
.t actual
()
13 losses, whether you lost it or you didn't lose it.
We have 14 looked at that in the past.
15 MR. MICHELSON:
That's your single event analysis.
16 MR, SZUKIEWICZ:
But what we didn't-look at it is
.17 this degraded or partial loss, and we think that you know, 18 looking at both sides of the, that issue, then you would 19 address your overall concern.
20 MR. MICHELSON:
The third thing--
21 MR. SZUKIEWICZ:
Regardless of what the cause was.
22 MR. MICHELSON:
The third thing you didn't look at, 23 and that is when they, failures are the consequence of some
{}
24 initiating event unrelated to the equipment, you looked at i.t 25 when the initiating event involved that piece of equipment, HERITAGE REPORTING CORPORATION -- (202)628-4888
76 p.
}
li bere is what happened.
That's your, that's the normal single
.2 failure modes and effect kind of analysis. 'That's the way you 3
do it.
You pick one thing at a time and you chase how far it 4-can go, 5
-Now we are talking about, we are talking now about a 6
pipe breaking, affecting this device which now has to be 7
changed on down, and the story, the scenario will be quite 8
different.
9 MR. BAER:
Now you are in PRA status.
10 MR. MICHELSON:
I am not in PRA status at all.
11 MR '. BAER:
We never get an issue prioritized and 12 certainly not through this Committee withouc putting it in PRA 13 status.
14.
MR. MICHELSON:
It can be put in PRA.
It is not a 15 PRA issue.
It is simply an issue--
16 CHAIRMAN SIESS:
You use PRA to decide whether it is
'17.
likely enough to decide to do something about it.
First you 18 have got to decide what can happen.
19 MR. MICHELSON:
Your PRA must correctly reflect the 20 fact that when the pipe breaks, this equipment is now being 21 overloaded by the environment created by the pipe break which 22 has not necessarily been looked at.
23 MR. SZUKIEWICZ:
Sure, but if we look at it from the
()
24 other aspect, if you do overload it with the environment, you 25 can, your failure modes can be, for instance, the air system HERITAGE REPORTING CORPORATION -- (202)628-4888
]
77
/~T 1
can be either a-total loss or a partial loss, or no loss.
Now Q
2~
we did leiok at loss and total loss and no loss, but we didn't 3
.look at partial loss.
4 MR. MICHELSON:
When you did that look, you did not 5
include the fact that the pipe, the pipe had already broken
'6 and caused a number of other things.
When you looked at the 7
initiating event wherein the air handling unit. quit one day, 8 ~
'you didn't look at that the air handling unit quit at the same
'9 time a pipe had broken.
That was not a part of that kind of 10 analysis.
11 MR. CASADA:
I think you can draw the parallel to a
12 the design basis, in the design basis events.
In the
( )'
'13L environmental qualification, you have the DBE occur.
It can 14 impact some things, plus since it occurred, you know you need-15 SCRAM.
You need to do those kind of things, so you make sure 16 all that equipment is protected, and the kind of thing he'is 17 talking about that is non-design basis, yes, it may damage 18 some HVAC equipment.
Your only concern is if it also causes a 19 threat to being able to shut down and safely cool in the 20 normal non-design basis aftermath, so the initiating event if 21 it doesn't affect RHR and SCRAM, I don't really care if it 22 affects HVAC, so it is the same kind of thing.
It is a very 23 large analysis because there is hundreds of pipes instead of--
()
24 MR. MICHELSON:
That's what the analysis has to be.
25 It is just as serious to break a water line out in the HERITAGE REPORTING CORPORATION -- (202)628-4888
b
[
78; q
- 1 '
building perhaps than it is to break a primary loop.
It'may
)l 2
.be'more serious in terms of ultimately melting the.co'e r
1 3
because if that break out there knocks out your ability to
~
l 4
cool the reactor, you are in deep trouble..
You have got to do l
5-that type of analysis for the pipe break.
l
.6 MR. SZUKIEWICZ:
That's why we have the flooding l
7.
issue.- It doesn't matter which pipes breaks.
l 8
MR. MICHELSON:
If you go back and look, you know, 9
.the issues, flooding issues didn't get into these kind of I
1O things at all.
Many of the flooding studies.said the water is.
11 rising from the floor level on up.
Didn't include it leaking
'12 down from the ceiling on some equipment that couldn't' stand
()
13 the leaks.
You go back--don't use the flooding issue as 14.
having covered this problem.
15 MR. BAER:
That's why we put it in A-17 and IPE.
16 MR. MICHELSON:
The IPE hopefully with the right 17-type of guidance will look for these kind of things.
See the 18 guidance to see what they are looking like.
19 MR. BAER:
Carl, I don't want you, to leave you with 20 the impression that we are going to be looking at 21-plant-specific interaction at a hundred plants in attempting 22 to prioritize these issues because there is just no way that
]
I 23 we have those kind of resources even if we had the necessary 1
()
24 plant-specific information.
)
25 CHAIRMAN SIESS:
Just look at it for the one plant HERITAGE REPORTING CORPORATION -- (202)628-4888
7---
{
s 79 1
i 1'
that.is likely to have the accident!
[
i 2;
MR. MICHELSON:
You are trying to identify the issue
]
l l
3-I thought.
I thought you were trying to identify the issue, j
i l
4 I was just trying'to help point out part'of the issue.
5 Now I don't say that that may--what I am saying, i
6 what you are going to do thereafter, if you refuse to identify
'I l
7
.the issue broadly enough to cover what we are talking about, l
4 8
then you really haven't identified the issue.
9 MR. SZUKIEWICZ:
We are covering it too broadly.
I 10 You just missed--
1 i
11 MR. MICHELSON:
Maybe we need to break it into three
'i 12 issues.
That's one of the ways'we do things, but where is
'I )
13 this one, you know, how is it covered?
14 MR. THATCHER:
We have agreement on that.
At least 15 some of it is in the flood.
16 MR. MICHELSON:
I would hope so, but I haven't-17 seen--
18 MR. CASADA:
We wil'1 get there.
Let's go through 19 the rest of them, and that one is one that we have on our list-1 20 to say how is this concern covered.
.i l
i 21 MR. THATCHER:
I think that point, maybe if that 22 doesn't cover it, then we can discuss it further.
23 CHAIRMAN SIESS:
I guess what bothers me a little
(}
24 bit was the response we got earlier that the emphasis on 25 multiple systems.
We are looking for not the single systems HERITAGE REPORTING CORPORATION -- (2021628-4888
_ _ - - _ _ ___ - - _ - _ - _ _ _ _ - _ a
80 1
failing,~but multiple systems failing, and I guess it isn't 2
clear to me t~1at al failure limited to a single system is-L 3
always benign no matter what caused it.
That's what Carl is l
4 saying.
If it is a random failure in a single system, fine.
5 That we have designed out.
But if it is a consequential 6
failure of a single _ system, we better be sure that what caused-7 it.
8 MR. CASADA:
Doesn't cause other things.
9 CHAIRMAN SIESS:
Doesn't change our-picture..
Okay.
10 It is not just multiple systems.
Onward!
11 MR. ROBERTS:
The next issue that we identified 12 denit with potential adverse effects on safety-related l
)
13 components either through direct contact with fire suppression 14 agents or through indirect interaction with non-safety-related 15 components that are affected by fire suppression system 16 actuation events.
17 The General Design Criteria 3 and 10 CFR 50, 18 Appendix R, set forth the requirements for protection of 19 safety-related equipment from. inadequate operation of fire 20 suppression systems; also being investigated as Generic Issue 21 57, originally designed to medium priority, which is'now under 22 consideration to high priority issue.
23 There have been a number of information notices that
()
24 have been issued describing events where actuation of fire 1
I 25 suppression systems had adverse effect on safety-related HERITAGE REPORTING CORPORATION -- (202)628-4888
81-1 equipment.
c O h
2 The status on this-issue, it appears that the l-
~3 Generic Issue 57 will fully address this concern, but that is 4
going to be, to be confirmed in the prioritization process.
l 5-CHAIRMAN SIESS:
As of June.22nd that was high.
6 MR. ROBERTS:
The report that you gentlemen were-7 issued was about a snapshot of a month and a half ago, so 8
that's consequently not reflected in there, but will be 9
reflected in the final version.
10 (Slide) 11 MR. ROBERTS:
The next issue, flooding, potential 12 for flooding or moisture intrusion, either'directly or 13 indirectly, affect through non-safety-related component 14 failures multiple trains of safeta-related equipment.
15 General Design Criteria 2 and 4 both require the.
16 safety-related equipment be protected from both internally and 17 e<ternally initiated floods.
18 There are a number of Standard Review Plan sections 19 that also address, provide guidance for designing and 20 analyzing the plant for flood protection.
21 Information Nctice 84-57 reported on operating 22 experience related to the moisture intrusion in safety-related 23 electrical equipment and also referred to an AEOD report in 24 which 53 events are were identified as being moisture 25 intrusion type of events.
HERITAGE REPORTING CORPORATION -- (202)628-4888 l
82
.1 At this time, it appears that the individual plant
~ O; 2
examination is going to. require plants to be examined for 3
vulnerabilities to internal flooding events.
Hopefully'in, 4
sometime in the future the IPE will also be looking at-
~
5~
external events, although both of these, the-guidance, the 6
guidance that is going to be presented for doing these types 7
of analyses really hasn't been finalized yet, so our status on 8
this is it appears that internal flooding will be specifically 9
addressed by the IPE.
10 However, this is not, this is going to have to be 11 confirmed by the prioritization process in the senst, of 12 looking at the guidance that is going to be presented for the
()
13 performing these IPEs.
14 MR. SZUKIEWICZ:
We have gotten some assurance it 15 will be addressed and there will be a letter coming out 16 discussing internal events sometime the end of this year, but 17-we will confirm it at that time.
18 MP. MICHELSON:
One item which maybe doesn't fit
.l 19 here but it is a problem described here, and that is during a, 20 even a modest fire in certain areas of the plant, we may find 21:
that perhaps the electrical boxes involved are located near 22 the fire, and as a result, the waterproofing seals which we there for particular reasons had been damaged or lost 23 put au
{}
24 by the fire even though the operability of of the board may 25 still be retained, but the difficulty you get into is when the HERITAGE' REPORTING CORPORATION -- (202)628-4888
F p.;
l:
L
- g3
[
1 people come in and start to mitigate the fire.or the
\\-
2 inspectors come on or whatever mitigating it, we have lost the' 3
intrusion capability of the electrical box so the water gets 4
into that box, then proceeds to 90 down to the conduits to the 5
next. floor below and the opposite train's electrical box,.and 6
you don't seem to treat that anywhere in the tire analyses 7
that are being proposed, and maybe it is in here somewhere,
'8 but it ought not to be lost as a potential difficulty involved 9
when we have fires that destroy the seals so to speak that 10 keep the water for the mitigation out of the opposite train.
11 In many cases, we are assuming that we
't, you 12 know, we check the four seals and doors and so forth:to keep
..()L 13 the water on the floor and not let it get away, but it might 14 get away through damage or mechanical or electrical equipment 15 that has been fire damaged enough.
We aren't counting on it 16 to operate even, but its sealing capability has been damaged 17 so that aspect which we are counting on has been lost, so we 18 would be well to at least pick up that thought somewhere when 19 they try to prioritize whatever issue that it fits with.
-i 20 MR. CASADA:
I think--I would see it being an issue l
l-l-
21 for GI 57, which is in our issue 14 here which talks about GI l
l 22 57 because like you say, the event that causes the damage to 23 the seal also requires somebody to come in and put the water
()
24 on that you don't want, so it is fire suppression related.
25 MR. MICHELSON:
57 might be the right home for it.
HERITAGE REPORTING CORPORATION -- (202)628-4888 I
J
i 84 1
Just'a couple of words to make sure it gets picked up there I O:
2
- think, s
3 In other words, if we are counting on the mechanical 4
integrity, even though we aren't count'ing.on the electrical 5
capability, we want to make sure that we don't lose that
.)
1 6
mechanical integrity even though the item was involved near or 7
in the fire area.
8' MR. SZUKIEWICZ:
Good point.
9 (Slide)
H 10 MR, ROBERTS:
The next series of issues all deal 11 with seismic events, seismically induced, the first one being 12 potential for seismic events to fail multiple trains of
()
13 safety-related equipment through spatial and functional 14 interactions.
15 1he report describes-a number of concerns related to 16 the integrity of small pipe under seismic loading spatial 17 interaction with non-seismically qualified components, and 1
10 functional interaction that may result in some undesirable 19 failures of say non-safety-related control systems, affecting t
20 protection systems.
l 21 General design criteria 2 requires that components 22 important to safety be able to withstand the effect of 23 earthquakes,
'( )
24 There are a number of Standard Review Plan sections 25 providing guidance for systems and subsystems such as they E ___
"""' " " """ " " " c "" * = " -- <202>s28-4888
85
- 1-comply with these general design criteria.
As a part of 2
resolution of USI A-46, Generic Letter 87-02 has requested the
.3 31censees verify the seismic adequacy.of the_ equipment by 4
comparison'to the experience data base.
l 5
Considering all the concerns, it appears that l-
.6 adequate guidance.probab1: exists for medium and large-sized K
'7 pipes, but there does not appear to be, specifically there 8
does not appear to be-any specific requirements that address i
l 9
failures of certain small piping and the-potentia 1'for 10
-associated systems interactions.
11 Therefore, this issue we feel'needs to be 12 prioritized.
()
13 CHAIRMAN SIESS:
There must be miles and miles'of-14 small piping in various industrial and commercial l
15 installations west of the Rocky Mountains.
16 Do we'have any experience at all with failures of 17 small pipes in earthquakes, unless they cross the fault?
18 MR. BAER:
I think the information experience from 19 seismic events, very severe ones, from industrial plants in 20 Chi?e and Taiwan for A-46, USI A-46, indicated that generally 21-there wasn't problems with piping in general unless there were 22 problems of physical interactions, things hitting.
23 MR. MICHELSON:
Pipes moving and tearing loose the
()
24 small lines, that was also a problem.
They have said we 25 aren't worried about it.
l HERITAGE REPORTING CORPORATION -- (202)628-4888
'86 1
CHAIRMAN SIESS:
It has never happened.
.O:
l L
2 MR. MICHELSON:
What do you mean?
3 CHAIRMAN SIESS:
I don't think SQUG found any piping
- 4 failures at any of the plants they looked at.
5 MR. MICHELSON:
They they didn't look at 1 inch 6
pipes.
l-
. 7.
MR. WARD:
I think they found failures in Alaska in 8
threaded piping.
If you make your statement as welded piping 9'
system--
10 MR. BAER:
Certainly it is part of prioritization, 11 and we will work with the prioritization people. -We will have 12 the people that were involved in A-46, you know--
()
13 CHAIhMAN SIESS:
The biccest danger it seems to me 14 would be something breaking loose and falling on the smaller 15 pipe.
16 MR. MICHELSON:
Or big pipes moving and small pipes 17 being anchored too well.
18 MR. CASADA:
I think that's--
19 MR. MICHELSON:
Yes.
That was not ruled out.
20 MR. CASADA:
In some of the systems interaction 21 walk-throughs that were done in various programs they went 22 through and they identified small branch connections that 23 people had improperly tied off, or that under dynamic (f
24 conditions one gets broken off, and they fixed a lot of those 25 kind of things in some plants.
HERITAGE REPORTING CORPORATION -- (202)628-4888
\\i 87 1
MR. MICHELSON:
Some plants.
'2 MR. CASADA:
Very few.
l=
3 MR. MICHELSON:
Let me, while we are talking'about 4
SQUG, I have a problem on page 117 in the middle of the page, 5
that sentence there, which Charlie can correct me if I'm 6
wrong, but I never got that impression with SQUG, and I will' 7
quote them.
"There were no malfunctions, false indications, 8
system resets, or abnormal occurrence of any form in power
'9 plant control systems..." during these earthquakes which are 10 mentioned.
I don't believe SQUG ever said that.
11 MR.. ROBEATF:
That's what was presented in the 12 presentation that SQUG made in the April ACRS meeting.
( ).
13 Mr. MICHELSON:
Show me a document of some sort that 14 says thr.c SQUG says there are none of these.
=15 MR. CASADA:
We will find out exactly where.that 16 came from.
17 MR. MICHELSON:
SQUG said, as I recollect, they said 18 we didn't have the kind of processes that would tell us all 19 the things going on.
We have had to look at the, at what was 20 left after the event, not what was dynamically occurring 21 during the event.
That was the argument I thought I had 22 heard, and how--you can't get this sentence if you, you 23 couldn't be correct unless you were monitoring during the O
24 eve t-25 If records, most post-event records showed indeed HERITAGE REPORTING CORPORATION -- (202)628-4888
88 e'
1 this was-true, then I' Id believe it, but my recollection 2
was they did not have that kind of information.
Some cases, 3
they had very little beyond the remains.
4 MR. SZUKIEWICZ:
We will verify, see what kind of 5
basis they have.
6 MR. MICHELSON:
I think it was probably just 7
stretched a little too far.
I don't think we can say that 8
strong a statement.
It is of any form, you know, kind of gets 9
pretty strong.
10 MR. ROBERTS:
We have to go back and look at that
-11 again.
l 12 MR. WYLIE:
Is this statement pertaining just to the
(
13 subject spatial-functional interaction?
14 MR. MICHELSON:
It pertains to the earthquakes'we 15 looked at, Charlie.
16 MR. WYLIE:
I know, but they speak to relay chatter 17 in another. issue.
18 MR. CASADA:
That is discussion of relay chatter, 19 which is the next--
20 MR. WYLIE:
That's enough.
I remember SQUG did say 21-they found cases where they had relay chatter.
22 MR. CASADA:
We will have to find out where that l
23 particular sentence comes from.
(
'24 (Slide) 25 MR. ROBERTS:
The next seismic issue of concern is l'
l' HERITAGE REPORTING CORPORATION -- (202)628-4888 w___-___-_:---
89
{
1_
the-potential for seismically induced fires to cause multiple l
2 failure of of safety-related equipment.
l-7 general-Design Criteria 2 and 3 both require 4
<afety-related equipment be protected from the effects of 5
earthquakes and fires.
6 However, the NRC staff has specifically stated in a 7'
branch technical position in the Standard Review Plan only 8
limited fire protection is required to post-earthquake 9
situations.
10 Therefore, this issue has not really been addressed 11 and has to be prioritized.
12 MR. MICHELSON:
On page 120, the very first
()
13 sentence, I think you didn't say what you meant.
It says the 14 regulations and guidelines for analyses of fire. events do 15 require consideration of fires concurrent with earthquakes.
I 16 think you meant do not.
Check it and see.
17 MR. ROBERTS:
What page is that again, sir?
18 MR. MICHELSON:
120, the first sentence, top of the 19 page.
20 MR. ROBERTS:
That should be do not.
21 MR. SZUKIEWICZ:
It is in the margin.
22 MR. MICHELSON:
I was surprised when I read it.
I 23 was being convinced, and all of a sudden I come to the summary
()
24 and it seemed to be 180 out.
25 (Slide) 1 l
HERITAGE REPORTING CORPORATION -- (202)628-4888
90 1
MR. ROBERTS:
The next issue dealt with potential
~
{)
2 for seismically induced fire suppression actuation to cause 3
multiple failures of safety-related equipment.
4 Once again, we have Generic Design Criteria that 5
states that safety-related equipment must be ab)a to survive 6
an SSE; 10 CFR 50, Appendix R, states that dedicated shutdown 7
capability must be provided where redundant systems may be 8
subjected to damage from inadvertent fire suppression system 9
actuation.
10 Generic Issue 57 which we have, I have already 11-mentioned, will investigate all available data associated with 12 common cause initiators or multiple fire protection system
)
13 actuation, including earthquakes.
'14 Therefore, it appears that GI 57 will include these 15-considerations, and it is to be confirmed by the-16 prioritization process.
17 MR. MICHELSON:
One point on this subject not to be 18 lost is the fact that fire protection systems in some cases 19 even today contain mercury relays which are, of course, 20 extremely sensitive to vibration, and they found a few of them 21 I think about a year ago at Peach Bottom or somewhere they 22 were looking, and then two or three other utilities found 23 some.
Maybe this is all corrected.
I don't know, but
()
I 24 somewhere in there you ought to emphasize particularly mercury 25 relays.
HERITAGE REPORTING CORPORATION -- (202)628-4888
91 L
1 MR. SZUKIEWICZ:
There was a bulletin to remove all 2
.those, but -I think it was limited to safety-related equipment.
3 Some of thisimay'not be safety related.
4 MR. MICHELSON:
This is fire protection.. This is.
5 not safety related.
'6 MR. SZUKIEWICZ:
Exactly right, so they may still-7-
have some.
8' MR. MICHELSON:
It may be triggering the diesel 9
engines like it did in that case, but at any rate, I think 10 that magic word mercury type relays or mercury welded relays 11 or something ought to appear just so specifically it does have 12 to be looked at in non-safety systems where we find them much.
(
13 more--I hope we don't have them in any safety systems anymore.
14 (Slide) 15 MR. ROBERTS:
The next seismic issue dealt with 16 potential for seismically induced flooding events to cause 17 multiple failures of safety-related equipment.
18 Once again, we have the same generic design' criteria 19 we have mentioned before that are supposed to be providing 20 guidance or requirements to design against the effects of six 21 seismic flooding events, including LOCAs.
22 Standard Review Plan Section 3.4.1 does provide 23 guidance for evaluating flood protection.
There have been
()
24 some studies done, performed, that investigated the response 25 of seismic Category 1 to earthquake excitation.
Right now it HERITAGE REPORTING CORPORATION -- (202)628-4888
,. 9 2
}
-1 appears that the IPE for external events will investigate 2
~ plant vulnerabilities to all external events, including 3
4 However, the guidance for this, for performing th~ose 5
IPEs, have not been issued, so at this point it appears that 6
this issue is not specifically. addressed by-existing programs.
7 It may be addressed by the IPE for external events, but'this l
8 is going to have to be confirmed in the prioritization l
9 process.
l 10 CHAIRMAN SIESS:
Is seismically-induced flooding any 11 better or any worse than some other kind'of flooding?
12 MR. CASADA:
I think a lot of people would try to j) 13
. convince you it is much worse.
There is a lot of, you know, 1
14 if such a thing happened, there would be a lot of confusion.
15 There'would be a lot of things to recover from, and flooding 16 wqould just be one more thing to confuse the issue and make it 17 worse.
18 MR. MICHELSON:
Seismic--
19 MR. ROBERTS:
Seismic events can cause a lot of 20 other things to happen.
21 MR. SZUKIEWICZ:
Multiple failures of those.
22 MR. MICHELSON:
On page 123 in your summary on this 23 particular item you talk about the regulation and guidelines
..()
24 that apparently exist in small piping.
Maybe I better quote 25 the whole sentence.
l 1
HER1 m E REP RT m C RP RA m N -- (202>s28-4888 o__ _ - _
93 l
1 "While regulation and guidelinesfdo exist for the 2
analysis'of potential-flooding of safety-related components 3
due to small piping and non-seismically qualified tank 4
ruptures..." and then it goes on.
They do not consider the-l 5
potential for multiple flooding events to occur during the l-6 earthquake.
7-My question is related to this guidance for small 8
piping.
I'm not aware of the guidance for small piping.
By 9
small, I think of 1 inch, for instance, as small.
10-Is there any guidance in the NRC on how to do an 11 analysis for i inch pipe ruptures?
12 MR. FORER15:
As far as I know, there'isn't
().
13 anything.
14 MR. MICHELSON:
As far as I know, I think they cut 15 it off at 6 inches or 4 inches, so somewhere the big stuff--it 16 is the little stuff that in the right circumstances, depending 17 on what else is in the room, might be very devastating, and 18 again it is those subtle things we are addressing here in 19 systems interaction, so I think you ought to clarify the 20 sentence or identify what is better meant because I don't 21 believe there is any guidance on small stuff, small in.the 22 sense of say 4 inch and under.
23-MR. ROBERTS:
We will look into that.
()
24 MR. SZUKIEWICZ:
I think we do address this.
Don't 25 we address this further down?
HERITAGE REPORTING CORPORATION -- (202)628-4888
d 94-
- i
.l 1
MR. CASADA:
I don't know.
We will just have to 2
look at it.
That paragraph,- when you like at-it out of
~3 context; looks like it could be revised easily.
Okay.
j 4-MR. ROBERTS:
The next issue deals with potential 5
for' seismically induced relay chatter to cause failure of 6-equipment required during and after a seismic event.
7 General Design Criteria 2 requires protection of l
8 safety-related equipment from the effects of seismic events.
I 9
Standard Review Plan, there are reg guides and IEEE 10 standards that provide guidance for seismic qualification.of.
11 equipment important to safety.
'j 12 The generic letter that came out of resolution of
()
13 USI A-46 included consideration of seismically induced relay 14 chatter.
There has been additional study performed that
.15 investigated relay chatter after a large earthquate from a PRA i
16 standpoint, and it indicated that plant-specific 17 vulnerabilities could exist.
18 At this point, it is possible that an IPE for
)
19 external events will also address this issue.
Therefore, the 20 status on this A-46 resolution, Generic Letter 87-02 21 specifically addressed this issue.
It appears relay chatter 22 may be addressed by the IPE for external events.
This is l
23 going to have to be confirmed by the prioritization process.
()
24 MR. MICHELSON:
This is where you might want to 1
25 mention the fire protection system and the mercury relays.
I i
HERITAGE REPORTING CORPORATION -- (202)628-4888
95 s
j j]
1 They certainly can cause, potentially cause.the loss of 2-
' safety-related equipment.
If-they were actuated,.if the 3
earthquake sets off the fire protection and you have to 4-account for the damageEto that equipment, in' conjunction'with 5
whatever the earthquake has caused, is an issue.
6 MR. SZUKIEWICZ:
Carl, on the issue of the small 7
piping on page 25, slide--
8 MR. MICHELSON:
Page 25?
9 MR. SZUKIEWICZ:
Or slide 25, on the enclosure where 10 we talk about that there is adequate guidance for medium and 11 large pipe, but it d.oes not appear that there is anything 12 specifically addressing small piping.
13 MR. MICHELSON:
Okay.
Then you will fix the summary 14 statement?
15 MR. SZUKIEWICZ:
Exactly, right.
16 MR. MICHELSON:
Okay..
I wasn't reading these 17 slides.
18 MR. SZUKIEWICZ:
Maybe in 16 and not 18 where we 19 talked about it.
I can, I can--I'm sure you meant not to 20 overstate it.
21 MR. ROBERTS:
The next seismic issue deals with the 22 evaluation of earthquake magnitudes greater than safe shutdown 1
j 23 earthquake.
()
24 The concern is that the adequate seismic margins may 25 not have been included in the design rf some safety-related HERITAGE REPORTING CORPORATION -- (202)628-4888
96 1
equipment.
%q-
_/
2-Right now it appears that the seismic safety 3
research program will include, which includes the seismic 4
design margins ~ program, will investigate the adequacy of 5
current seismic design margins.
Therefore, it appears that 6
this particular issue is being addressed.
That's to be 7-confirmed by the prioritization process.
8
-MR. MICHELSON:
Fou is, how do we consider, you 9
know, once you go beyond the seismic design basis, what kind 10 of equipment behavior do we start assuming if things still 11 work as well as they did within the design basis, or certainly 12 not everything suddenly failed because you slightly exceed?
()
13 CHAIRMAN SIESS:
How do you design fragilities?
I 14 think basically you define go, no-go.
15 MR. MICHELSON:
But I can see how you do it for 16 mechanical things that you do some kind of an analysis on.
17 What do you do on an electrical device which you 18 have never tested in these ranges which it is difficult to 19 analyze?
You have to go back and do some testing I guess.
20 CHAIRMAN STESS:
Some of it has been done by tests.
21 Some of it has been done by expert opinion based on test or 22 experience.
They have got fragility..
They have done the 23 seismic margin study.
They have developed some sort of
()
24 fragility curve of every piece of equipment.
25 MR. MICHELSON:
They didn't do it for every piece of HERITAGE REPORTING CORPORATION -- (202)628-4888
97 1
equipment because it incluoes, I mean.now we are talking about-2 system interaction, so I am talking about say fire protection 3
which.is not even seismically qualified to begin with.
I 4
Ldon't know how.it behaves bigger than SSE.
5-
. CHAIRMAN SIESS:
The people that can estimate the 6
1ragility of a Category I system can estimate with equal. skill the fragility'of a non-Category 1 system.
There ain't that-7 8
much difference.
9 MR. MICHELSON:
My point is when I have seen these 10 beyond the SSE studies, I have never seen them include such 11 things as what happens to the prior protection and now you 12 actuate and' start doing this and that.
()
l 13 CHAIRMAN SIESS:
The only one I know of is--
14 MR. CASADA:
It is not surprising since they haven't 15 done the study about what happens to the fire protection 16 piping below the SSE.
17 MR. MICHELSON:
I am agonizing over the fact that l:
18 these are narrow studies of certain components and not 1:
19 necessarily a study of how the plant as a whole would respond 20 to a beyond the SSE, yet we take great faith in some of the 21 conclusions drawn from some of these studies about gee, we can j
22
' stand two times the SSE, whatever.
l 23 MR. BAER:
Maybe the place to mak_ that point is on
()
24 the issue about multiple fires from seismic events, and point 25 out in our text for the people that prioritize it that there s
HERITAGE REPORTING CORPORATION -- (202)628-4888
98.
1 are concerns-about-the fire protection system operability or 2'
even structural integrity as you do seismic events..
3 MR. MICHELSON:
I thought, I. thought, though, this 4
was, 21 is'the ideal issue.
It says evaluation of earthquake 5
magnitude.. Maybe they mean just how do you figure out what 6
the magnitude is.
I didn't think they meant that.
7 CHAIRMAN SIESS:
No--seismic.
l 8
MR. MICHELSON:
It is seismic, behavior of plants 9
beyond the SSE..
That's the place to put it.
10 MR. BAER:
Just as you said, Carl, I am not so sure 11 when people.look at beyond the SSE, they are going to start 12 postulating fire.
They are not going.to look at quote, L
l
)
13 non-seismic equipment in most cases.
14 MR. MICHELSON:
Like fire protection, inducing a l
15' fire.
I am just saying'what happens to the fire protection l
16 and instant response.
It could affect all the' diesel engines, 17 that sort of thing.
18 CHAIRMAN SIESS-The main characteristic of an I
l 19 earthquake is that it is global.
It affects everything at the 20 same time, not to the same extent.
Somebody once said you l
21 find all new mistakes once at the same time.
The larger the 22 earthquake, the more likely it is to damage something.
Now 23 that's typi cal.
I don't think there is any question about
()
24 that.
25 Up to the SSE, much of the plant, much of the HERITAGE REPORTING CORPORATION -- (202)628-4888
L
[. -
0 99 1
l L
f(r~}1 Category 1-equipment has been qualified with margins-1 L
3-2 obviously.
3 The concern is that there are things that. haven't 4
been qualified that might be damaged.
The question of.other
.5 non-safety systems, and it is the problem that.there might be
-6 simultaneous damage to more than one system.
Now that's the-7 essence of a seismic problem.
You can. break it up into 8
floods,' fire, whatever, but it is potential for causing 9
multiple f ailures, and obviously that potential gets greater, 10 the larger the earthquake, it gets greater to some extent.
11 The less safety significance something is.,
although 12 I'm not completely convinced that safety grade.is that'much-()
'13 better than non-safety grade, and I think'you have got the 14 seismic. thing bruken down too much here.
Maybe it has to be 15 broken down this'way, but again, if we can eliminate fire, 16 seismically-induced fires, that's only one little piece of'it.
17 We.have to eliminate seismically-induced floods.
18 Maybe you hcVe to break it down.
Maybe that's the best way~to 19 do it, but unless they can be eliminated, they all come back 20 together again.
They are seismically-induced multiple 21 actions, so I think in resolving these types of issues, 22 fragmenting them as you have done, separating them, is good to 23 the extent that it allows you to eliminate something., but if
()
24 it doesn't allow you to eliminate them, you are better off 25 aggregating them back into the single multiple failure issue.
1 HERITAGE REPORTING CORPORATION -- (202)628-4888
100-m
~
- f^p
'l Of course, the fact that the-seismic hazard.has-kJ 2
tremendous uncertainty means that any time anybody does.a.PRA, 3
it becomes an issue because of uncertainty.
The real danger 4
is the multiple failures.
5 (Slide) 6 MR. ROBERTS:
The next issue isn't related to 7
seismic, isn't directly related to seismic events.
- Hydrogen, 8
the hydrogen line rupture that cause subsequent fires and/or 9
explosion which could damage multiple trains of safety-related 10 equipment.
11 Hydrogen lines and line ruptures.in general are 12 addressed in the Standard Review Plan which states that
)
13 hydrogen lines in safety-related areas should be designed to 14 prevent hydrogen concentrations from exceeding 50 percent of.
15 the lower flammability limit in the event of a hydrogen line 16
-break.
17 Generic Issue 106, piping and the use of highly 18 combustible gases in vital areas, addresses protection of 19 safety-related equipment from the effect of hydrogen line 20 breaks.
It has currently been given a medium priority.
21 MR. MICHELSON:
One question--when you refer back to 22 the branch technical position, you really have to look at 33 whether or not it was implemented on a given plant, something, l' ()
24 you know, Appendix R, the whole bit, and don't be surprised 25 when you find hydrogen lines around the building that aren't l
HERITAGE REPORTING CORPORATION -- (202)628-4888
101 double contained and don't have excess flow checks, all these,
(}l 1
2 so somehow we have to make sure that the reader understands.
3 many plants out there may be of the old variety, and the 4
concern is not so nicely put away by sayiny we have got all-5 these: positions because we didn't necessarily have the 6-Epositions that applied to some of those older vintage plants, 7
so it gets a little misleading to look at all the good stuff 8
that applies when it really doesn't apply.
9 CHAIRMAN SIESS:
Just recently there was'a plant 10 that had hydrogen storage on the roof of the building.
11 MR. ROBERTS:
Right next to the ventilation intake 12 to the control room.
)
13 CHAIRMAN SIESS:
Now that could be a seismic issue.
14 It could be a tornado issue.
You know, it could be a lot of 15 others, but I'm sure that some sort of an information notice 16 went out on that.
17 MR. CASADA:
It did.
18 CHAIRMAN SIESS:
Anybody else have one?
Or was it 19 unique?
l 20 MR. CASADA:
It was a notice.
It doesn't require 21 response.
I don't know that you would know.
That was a 22 notice that described that specific event.
I don't know if 23 the staff knows if there were anybody else who found tanks
()
24 where they shouldn't.
25 CHAIRMAN SIESS:
In relation of what Carl just said, i
l l
i HERITAGE REPORTING CORPORATION -- (202)628-4888
102 1j f/N 1
about'95--one doesn't go1back all that far.
I was trying to ag
~
2 recall the systemat'ic evaluation program plan.
We looked at 3
'the nine owners' plants, and I'm sure not one of it would have l
4 been covered by this, but I don't think this was either one of L
5.
the items that were looked at in the SCP.
6 MR. MICHELSON:
Probably not.
l 7
CHAIRMAN SIESS:
It was narrowed down to 120 items 8
or so.
9 MR. THATCHER:
That's why there is a generic issue
\\.
l 10 106, to look at some of these.
I think that was part of the 1
11 prioritization, the fact there were the--
-12 MR. MICHELSON:
We are just thinking more about the
)
13 problem now.
Going back to the previous question, my 15
-experience when I was in INE is that I think licensees and the 16 inspectors do a pretty fair job following up on'information 17 notices, at least for the explicit issue that is covered.: I 18 don't think that somebody else has a hydrogen tank sitting on 19 the roof.
I think that would be found now.
Something more 20 subtle, and that I wouldn't be as--
21 MR. MICHELSON:
Is there some kind of requirement 22 the resident inspector inform the region they found it?
23 CHAIRMAN SIESS:
Don't worry.
He would.
])
24 MR. MICHELSON:
Maybe the regional guys--how does 25 headquarters find out?
HERITAGE REPORTING CORPORATION -- (202)628-4888
v" 103 1
MR. BAER:
Okay.
I thought the question was would
'}
2 it be fixed?
3, CHAIRMAN-SIESS: -That wasn't my question.
I was t
4 just< interested in the statistics.
5 MR. BAER:
No.
6 CHAIRMAN SIESS:
A hundred and 20 plant type-of 7
thing--
8 MR. MICHELSON:
Would you know so that you.could 9
accumulate the statistics and tell us how many cases and what-10 kind of cases?
11 MR. BAER:
There isn't an easy mechanism for that.
12 MR. MINNERS:
106 is not going to answer that 13'-
question.
14 (Clide) 15 MR. RGBERTS:
The final' issue that we are presenting 16 today deals with :he lack of specific actions that related to 17 the systems interactions.
1 18 CHAIRMAN SIESS:
Why is that the last one on the 19 list?
20 MR. ROBERTS:
This-is the last one on the list 21 because it, it turns out some of the issues that have been 22 brought out or concerns that have been brought out that 23 weren't in the original resolution of USI A-17, that was one
()
24-of the issues, and this issue was there wasn't any specific 25 requirements to look at some things, certain areas.
HERITAGE REPORTING CORPORATION -- (202)628-4888
I 104
(~
1 Some of the MSR issues that we presented'here are in 2
fact looking at some of these. areas, and so we decided to 3;
place this issue last to kind of look back in retrospect 4
saying at least some of these areas are being looked.at.
5 With regard to lack of specific requirements for 6
licensees to respond to systems interaction concerns that are 7
defined in USI A-17, and with the lack of specific 8
requirements for action imposed on licensees for' performing 9
spatial SI studies, we tried to address spatial interaction 10 in some of.the MSR issues that we have already defined, and we 11 have also tried to, tried to address some of the concerns that 12 may have come out regarding those concerns that weren't
(
13 addressed in USI A-17 in some of these MSR issues.
14 CHAIRMAN SIESS:
It seems to me that this issue is a 15 procedural issue or a regulatory issue.
It is a complaint 16 that now how did the staff handle A-17?
The generic letter?
.17 MR. THATCHER:
In the generic letter on A-17, there 18 is section on information for licensees to use this, their 19 ongoing--
20 CHAIRMAN SIESS:
There were no requirements?
21 MR. THATCHER:
Yes.
That's why it says no specific 22 requirements in that.
23 CHAIRMAN SIESS:
No backfit analysis, no
(
24 requirements placed?
25 MR. THATCHER:
Right.
HERITAGE REPORTING CORPORATION -- (202)628-4888
g 105
.1
'MR.
CASADA:
But in that first bullet where we say.
)
D 2
there were no specific requirements, the things.that were of 3
concern in A-17 involved-thicas like flooding, electric power, 4
support-systems, the kinds of things that some of the other 5
issues we have here now should put in a package to bc 6
prioritized.
7 CHAIRMAN SIESS:
No specific requirements to do 8
these, either?
9 MR. CASADA:
There may not be.
It depends on how 10 they are prioritized and then how they are resolved.
11-CHAIRMAN SIESS:
They may be resolved by saying 12 something ought to be.done, but without putting specific 13 requirements on.
14 MR. CASADA:
That's true.
15 CHAIRMAN SIESS:
It is a regulatory question.
16 MR. ROBERTS:
The lacks of dedicated 17 interdisciplinary groups for identifying plant-specific 18 sis--here generic and plant-specific sis can be identified by 19 the current lessons learned program such as INPO operating 20 experience program, NRC reviews of LERs, and utility operating 21 experience reviews as a result of post-TMI requirements.
22 In addition, the IPE generic letter requests 23 licensees to identify plant-specific vulnerabilities to severe q(}
24 accidents, so it may be that the IPE may actually be covering 25 some of these items as well.
HERITAGE REPORTING CORPORATION -- (202)628-4888
g.
106 li
'As a result, the status on this issue, as a whole, 2
the general concerns related to generic problems are 3-considered, are considered or may be considered in_the NRC and 4'
industry programs.
5 The other issues, as we said, specific issues, 6-concerns in which no regulatory action was taken, no action-7 was required, may. eventually be prioritized as some-of these 8
MSR issues that have already.been identified.
9 CHAIRMAN SIESS:
I wonder if the IPE is going to 10 find the subtle types of interactions that we have been 11 talking about this morning?
12 MR. MINNERS:
If the IPE doesn't, what,would?
l():
13 CHAIRMAN SIESS:
I. don't know.
I'm just wondering 14_
why there is a need for the dedicated interdisciplinary group.
15 Carl Michelson all by himself finds an awful lot of them.
If 16 Carl Michelson can find five times as many or'25. times as many 37_
or it takes a particular way of 1 coking for these things 18 that--
19 MR. CASADA:
I guess one of the questions we would 20 like to ask--this was a stated concern that is about as old as 21 any of them--the lack of a group that does this.
This comes 22 from the days when there used to be a systems interaction l
23 branch and then there wasn't and there were reorganizations 1 ()
24 and if this was stated, I don't know if it is a current 25 concern of the ACRS.
HERITAGE REPORTING CORPORATION -- (202)628-4888
307 1
1 MR. MINNERS:
I thought.we resolved this with A-17.
2 CHAIRMAN SIESS:
That member is no longer on the 3
Committee, so I don't know whether.it is a current concern or-4 not., either.
5 You know, I think looking for systems interactions 6
is more a state of mind than it ir, an interdisciplinary 7
effort.
You have got to have a-feel for. things that can 8
happen, and the other thing that you have got to have.is to be 9
able to extrapolate from one incident has happened to you say, 10 to others of the same ilk that do happen in your plant.
It is 11 a state of awareness.
I know where this came from, what 12 3etter it came from, and it is on the record.
()
13 MR. MINNERS:
I think my view at least is that-A-17 14 resolved these questions.
That to me was the thrust of the 15 issue.
Should we have some kind of system management program, 16 either by the NRC or by licensees or by somebody to look for 17 severe interactions?
And I think A-17 said no, it's a nice 18 theory, but we don't think there is any really effective way 39 of doing that.
20 CHAIRMAN SIESS:
The Indian Point review, what did 21 we get out of that?
That was a systematic walk-down?
l 22 MR. MINNERS:
We got some ceiling panels falling 23 down on guys.
()
24 CHAIRMAN SIESS:
That was for the seismic PRA.
25 MR. BAER:
We actually have two different studies.
HERITAGE REPORTING CORPORATION -- (202)628-4888
108~
L
'l Dale, why don't you describe them?
We found very little is L
2' the punch line, but go ahead.
3 MR.-THATCHER:
Well, are you referring to the study 4
that the NRC had?
5 CHAIRMAN SIESS:
ACRS assisted in Indian Point.
li 6
MR. THATCHER:
That was'a utility study.
7 CHAIRMAN SIESS:
Indian Point did a systems-8 interaction review of the plant, including the walk-down by an 9
inter' disciplinary group, and they came in with a' report on it.
10 Now that is a-systematic review.
I don't remember ~what they 11 found, and I don't get an awful lot of comfort from that-kind 12 of a one-shot thing.
I think that it has to be a continuing
( )'
13 state of mind of looking for these things and fixing them.
14 MR. BAER:
As you said earlier,' observing events at 15 other plants and extrapolating them and see how they might 16 apply to your project.
17 CHAIRMAN SIESS:
The industry doesn't do that.
The
.18 NRC doesn't do it.
I don't know how it gets done.
I don't 19 know how much INPO and so forth to cover these sorts of i
20 things.
21
'MR.
SZUKIEWICZ:
We do do it to some extent.
We 22 review the LERs.
If there is a general situation, we do issue 23 information notices or bulletins.
INPO does the same thing.
()
24 And AEOD, for example, does it in more detail.
25 MR. MICHELSON:
You know as well as I that issuing HERITAGE REPORTING CORPORATION -- (202)628-4888
109 11 b'
~
1 the information bulletin in'the utility doesn't make anything 2'
happen.
The utility must then decide whether or not its own 3
plant-specific situations are vulnerable to whatever is 4
described, and there is no requirement for that kind of an 5
analysis of an information notice.
6 MR. SZUKIEWICZ:
It is addressed by the resident 7
inspector and he does satisfy himself on how these things were l
'8 addressed.
9 MR. MICHELSON:
You think these information notices i
10 prescribe that you must take your plant-specific situation out-11' and look for system interaction?
Based on what you are saying i
12 from this information notice, it didn't say that.
)
13 MR. MINNERS:
I don't understand what you are 14 saying.
The reason it is not a balletin, before people put 15 out an information notice, they decide whether it should be a 16 notice or a bulletin, whether it should be just information or
'17 whether it should be a requirement.
18 MR. MICHELSON:
You really don't understand the 19 plant-specific situation well enough to realize that.
It's a 20 somewhat mundane event, but other--an information notice could l'
21 be a very serious event for a particular plant out there.
You 22 don't know that.
23 MR. MINNERS:
That's true.
()
24 MR. MICHELSON:
The utility doesn't know that.
They 25 can be potentially in trouble.
HERITAGE REPORTING CORPORATION -- (202)628-4888 L___.___._.________m
110 CC 1
MR. MINNERS:
You can say thst about anything.
'2.
MR. MICHELSON:
But'I am saying don't count on 3
inf ormation notices--
L 4.
MR. BAER:
I used to be involved in this process.
5 Long before you get to the information notice--it is not a 6
perfect process, but it is a pretty thorough process where 7
every. morning, a group of people go through all the daily l
8-
' reports from the licensees, the PNs that have come in, discuss 9
them,c and try and determine which ones should be followed up, 10 and those'that, you know, seem like they would have some 11 safety significance are assigned for somebody to follow up.
Then there is a once-a-week briefing of management l
12
()
13 on those issues that seem to be the most important ones, and 14 so if people can't make--I don't know how you make, quote, 15-people smarter, but certainly there is a conscious effort for 16.
people to look at all the~ events that are happening, and to 17 see what their potential' significance is, and--
18 MR. MICHELSON:
You missed my point then I guess 19 that I was trying to make.
20 MR. BAER:
This is before anyone decides to write an 21 information notice.
22-MR. MICHELSON:
You might decide those are not-23 worthy of an information notice for that particular event, but
- ( )
24 you do not know about the particular plant-specific situation 1
~
25 where it could be a very serious concern, so you don't even HERITAGE REPORTING CORPORATION -- (202)628-4888
111
{}
1 issue an information notice.
The meeting doesn't kick this 2
aroun('because,they don't even know about it.
3 MR..BAER:
That aspect is true, but also people do 4
go through n conscious thought process hey, is this a 5
potential precursor to something?
6 MR. MICHELSON:
I think I understand how this 7
process works.
8 MR. BAER:
I don't know how you make people smarter.
9 MR. MINNERS:
The example of the hydrogen tanks by 10 the control room, that seems to me like an obvious problem 11 that the utility should have recognized.
I don't know how you 12 solve that problem.
How do you make people look at that stuff
(
13 and fix it?
34 MR. MICHELSON:
You might at least require that they 15 do some more systematic examination than they do.
16 MR. MINNERS:
They walk by it every day.
I would 17 think the operators would have gone to their' union and said 18 fix it.
19 DR. KERR:
Considering how rapid the hydrogen rises 1
J 20 when it is released, that might be the best place to put it!
21 CHAIRMAN SIESS:
There is a risk basis.
You find it 22 wasn't all that big a problem.
It was just something on the 23 face of it, didn't look like a real good idea, but you know, I
l
()
24 NRC cannot sit down and look at details of 120 plants.
25 What is more. I don't think NRC can write l
HERITAGE REPORTING CORPORATION -- (202)628-4888 l
L..
n
~
112 l
L
' /~s.
1 regulations that will cover the kinds of things we'are talking D
2 about here.
For God's sake, we have been writing regulations 3
for 25 years, and if they don't cover it now, they are not 4
likely to get any better tomorrow.
5 MR. MINNERS:
We quoted a lot of regulations, and 6
they don't do it.
7 CHAIRMAN STESS:
If they are all working and they 8
don't interfere with each other and everybody understands 9
them, you know, the plant is in pretty good shape.
I really 10 think systems interactions and adverse systems interaction are 11 things that the industry must be aware of and NRC must be 12 aware of, and it is not easy for good--what is very benign at
()
13 one plant might be quite serious at another one and 14 vice-versa, and I think it is a,.as I said, it is a state of 15 mind.
It is a way of running your business, of looking out 16 for these things.
These are very complicated systems and they 17 are going to interact, and all the interactions aren't going 18 to be good, and all we do is keep looking for them.
19 Don't ever think we have got it resolved.
That was 20 the main point I think we were trying to make with A-17 is.
21 resolve A-17, but let's don't say we have resolved systems 22 interaction because we are kidding ourselves.
23 MR. MINNERS:
I will say again I think that's why we
.( )
24 established a generic issue program which is an ongoing 25 program which is supposed to identify these system HERITAGE REPORTING CORPORATION -- (202)628-4888
r4 113
/s 1
interactions and other safety issues, try to get them fixed' i.d-2 MR. MICHELSON:
At least try to develop enough 3
guidance so that the people who really know their plants can 4
use that guidance to find out if they have got a problem.
5 I don't find. good guidance around on.this subject at i
j 6
all. _Maybe there is, you know, I haven't looked.at at.
I 7
. don't find it.
8 Why not put a major thrust.on the development of 9
good guidance by the Agency?
You might say gee, the utilities 10 ought to do it themselves.
This is something I think-the 11 regulator ought to do to help protect the public health.
12 DR. KERR:
Are you convinced that the staff has the l) 13 resources to develop good guidance for this?
1 14 MR. MICHELCON:
I think they do.
If the staff 15 doesn't have it, they will get contractors do it.
16 MR. SZUKIEWICZ:
In some cases, we provided a lot of 17 detailed guidance.
By the-time it goes out, it gets diluted 18 because you are too specific and--
19' MR. MICHELSON:
I am thinking of regulatory guides 20 now because they have some kind of regulatory connotation
)
21 which elevates them too far.
I am talking about just some i
22 good guidance discussions, good reports, you know, NUREGs or 23 whatever, which convey this kind of guidance but don't have
' ()
24 any kind of a power of regulation.
25 CHAIRMAN SIESS:
Did we ever have a system I
I
.]
1 1
114
'1-interaction users group?
J2 MR. THATCHER:
We--at one time, the former Atomic
~
3 Industrial Forum had a group of industry representatives 4-working'on the systems interaction issue.
5 CHAIRMAN SIESS:
To what extent has INPO looked at
'6 it?
Is this part of INPO's scope?
These'are design problems 7
more than operational ones.
I never quite understood where-
'8 they ended up.
MR. THATCHER:
Well, they look at operational 10 events.
I.mean INPO does.
11 CHAIRMAN SIESS:
This is more than looking at events
-12 to see whether there is a deficiency in the design or the'
(
13 layout or the procedures that.could make it a problem.
Events-l 14 are, just include potential interaction.
Does INPO include 15 that sort of thing?
16 MR. MINNERS:
I don't really know.
I think they 17
-Icok at, more at operating experience.
I don't think INPO 18 goes out and makes a PRA to try to discover system 19 interactions, other design defects.
20 MR. MICHEhSON:
I believe if you just look at the-21 SER and O&M type document, which is the predominant product in-l 22-this particular area, you do not find this sort of guidance in 23 there except on rare occasions.
If they look at it, they
()-
24 don't, certainly don't publish about it, to my knowledge.
25 Maybe they stick it on their telegraph or something.
I don't l
1 i
l.
]
' HERITAGE REPORTING CORPORATION -- (202)628-4888
115
('T
.1 know, but certainly they don't seem to come out with any kind
%).
2 of formal documents which they dealt with these. issues.
3 NSAC to my knowledge doesn't do it, either.
I 4
haven't seen any NSAC documents.
The fact is'I'm not sure 5'
even it does any writing any more.
I don't see anything 6
coming out of NSAC.
Maybe that's where it ought to come from 7
rather than INPO.
8 CHAIRMAN SIESS:
Have you completed your 9
presentation?
10 MR. ROBERTS:
Yes.
That's all we have this morning.
11 CHAIRMAN SIESS:
Would you like to sit down?
12 MR. ROBERTS:
Yes.
13 MR. CASADA:
I would like to thank you for comments 14 both on the discussion we had and on the report, and if you 15
'have others, we welcome those.
We will be taking these kinds 16 of comments and putting that into the revised report that Andy 17 talked about that should be available in a month or so I 18 believe.
19 CHAIRMAN SIESS:
We have got an hour according to 20 our schedule, and I would like to see whether the other 21 members of the Subcommittee here have any comments.
22 I think that there are two categories of comments we 23 are looking for--are there things on this list--and by list,
- ( )
24 it is this group of items--that you would tell the staff to 25 forget about and not bother to go with the prioritization?
HERITAGE REPORTING CORPORATION -- (202)628-4888_
f-g I"
116 i:~
'1'
- And second, are there items or categories that
- (
2 aren't on that list that ought to be pursued on some basis?
l.
3 I am going to start down at the far'end with Charlie 4
Wyle.
Each has had A-46, for example, 5
MR. WYLIE:
I think they have'done a good job of 6
identifying the i sues that you ought, that ought to be 7
considered for prioritization,.and-I can't think of anything.
8 I got sort of one that we are following a little 9
bit, and trying to see how much evidence there is that we 10 should pursue it further, and that has to do with lightning 11 effects on plants.
Several years, AEOD followed-that severall 12 years ago, issued a bulletin I think, but it-continues to come-(
13 up.
Just recently a plant, Grand Gulf I think, notice was 14 issued where lightning affected their nuclear instrumentation 15 in the plant, shut them down, and that continues to happen.
16 A13 it points up is there is a deficiency in the 17 lightning protection and grounding at those plants, and it is 18 something that is easily fixed, and I would have thought that 19 the bulletin that went out several years ago might-have had 20 something, some effect on that, but now whether that should be 21 a generic issue or not, I don't know.
That's something we are 22 trying to pursue in the subcommittee.
23 CHAIRMAN SIESS:
Your subcommittee is working on it?
()
24 MR. WYLIE:
Yes.
25 CHAIRMAN SIESS:
Because to raise a more general HERITAGE REPORTING CORPORATION -- (202)628-4888
.: (
.117
'l question that.I would'like to surface'here, assuming ACRS says 2
gee, this is a good list, haven't got anything to add to it 3
right now, then what has that to do about things we might 4
.think of in'the future?
S' Now when a generic issue process was set up, we set 6
up--I don't know if we ever did it officially within the 7
ACRS--a process for the ACRS identifying generic issues.
We.
8 have that right.
The public has the right, and in fact a lot 9
of the original generic issues to'begin with we combined our 10 list, so we have a way of formally identifying it and saying 11 this is a generic issue, you guys prioritize it.
I don't
'12 think we have done it in that sense ever.
()
13 What has happened here is you picked up on our oral, 14.
written consensus and non-concensus statements and are looking 15 at them, and are willing to treat them that way, so in the 16 tuture, we can still come up with concerns and apparently 17 whether or not the Committee agrees as a Committee that this 18 is a concern, if somebody repeats it often enough, the staff 19 will pick it up and look at it, but lightning, that Charlie 20
-mentioned his subcommittee is working on it, if he decides it 21 is something, he will state, he will write it up the same way, 22 will try to get it written up the same way you require them to 23 be written up in your organization.
I'm sure I can get all
()
24 that out of anybody, but you know what I mean.
25 Charlie, I just want to bring that up because we do HERITAGE REPORTING CORPORATION -- (202)628-4888
118 1 ~
have a way of generating generic issues formally.
2-MR. WYLIE:
Well, we will pursue that one.
3 CHAIRMAN SIESS:
We are stating it more clearly than 4
sometimes we have in the past.
5 MR. WYLIE:
Back on the issue of degrading electric 6
power systems, the comments pertaining, seem to pertain mainly 7
to'either low voltage or high voltage, this type of thing, but 8
I assume when you prioritize'that, you will also look at the 9
frequency.
10 MR. CASADA:
That is stated fairly narrowly now, 11 1 that degradation could be frequency as well as voltage.
12 MR. WYLIE:
Yes.
Could be a system disturbance such 13 as a blackout of a whole region.
The frequency could sag 14 quite a bit and the unit still staytied to the system for 15 quite a while.
16 MR. SZUKIEWICZ:
You are talking about frequency
'17 degradation, not the frequency of degradation?
18 MR. WYLIE:
No--electrical.
19 MR. SZUKIEWICZ:
I see.
20 MR. WYLIE:
Currents--that's all I have.
21 CHAIRMAN SIESS:
Dave?
22 MR. WARD:
I don't have any comment.
23 CHAIRMAN SIESS:
Forrest?
()
24 DR. REMICK:
Just some general comments--I agree 25 very much with the things that have been stated in the past HERITAGE REPORTING CORPORATION -- (202)628-4888
s 119 r-1
.by, several members have stated this morning that the systems
..h) c 2
integration is something that you are never finished with, and
.3' I don't1think we will ever get our arms completely around the
~
4 problem, so I think we would be kidding ourselves if we 5
thought we did have our arms around it now,'but I do think the 6
contractor has done a yeoman's job of trying to take these 7
various things and put them into a set of issues which some'of-1 8'
the refinements that Carl and others have pointed out this
'9 morning, that it is a very good start of trying to 10 characterize these various issues.
11 I hope it is clear as Mr. Minners pointed out, that 12 although our minutes and transcript give you insights on
()
13 discussions, that ACRS' positions are expressed by our letters, 14-so our discussion earlier about have you read the minutes or-15
.the transcript, you might get some insights on how that 16 particular position was arrived at, but certainly we never 17 expect the staff to respond to everytbing that is-said in the 18 subcommittee meeting or what is in our minutes.
Positions, 19 collegial positions, are identified by letter writings.
20 All in all, I think it is a good effort.
I'm sure 21 as Mr. Casada points out, from time to time there will be new 22 issues that will identified or others identified, and I think 23 that's how we should approach the subject.
l g()
l 24 CHAIRMAN SIESS:
Carl, any last words?
25 MR. MICHELSON:
I think one of the comments that I HERITAGE REPORTING CORPORATION -- (202)628-4888 l
~
J 120 l'
would'like to make clear'that we all appreciate,..'an'd that is 2
this document is composed of in some cases ACRS positions, in 3
some cases individual comments made by.ACRS members, and other 4
cases, it is not even clear where it came from, but that kind
- 5 of stated here is another generic concern and without 6
identification where it came from necessarily wlich I don't 7
object to, but this document is not a compilation of'just ACRS 8
positions, and you know, we must appreciate that many and j
9 much, not all, of it, but a considerable amount of this was 10 never stated in letters, was kicked around from time to time 11 extensively in meetingr, but it never necessarily was put in 12 letters.
In some cases it appears as, it appears as proposed 1( )
13 letters, but the letters never got issued, but not necessarily 14 because of the merits of the material but because of the other' 15 considerations, so we do have to appreciate that this is, you 16 know, this is not a document that just reflects ACRS Committee 17 positions.
18 CHAIRMAN SIESS:
I don't think we should care where 19 it comes from.
It is what they do with it.
20' MR. MICHELSON:
I think we should care if we see 21 something here that we violently object to saying it is even 22 an issue.
You know, see something we just don't believe it is 23 an issue, we certainly, we ought to eliminate anything in here
()
24 we think is simply not an issue.
25 CHAIRMAN SIESS:
Have you got any suggestions?
i 121 1
1 MR. MICHELSON:
No.
I have no suggestion at all.
2 LDR. REMICK:
Isn't the priority setting process 3
going to eliminate some?
4 MR. MICHELSON:
Oh, yes.
5 CHAIRMAN SIESS:
Prioritization'we will review
~
6.
ongoing.during the course of business.
7 MR. MICHELSON:
That's when the Committee will
'8 finally express its views as to whether that particular' aspect 9
of issue or that issue as a whole should even be considered, 10
'but--
11 CHAIRMAN SIESS:
This may be rearranged and 12-
. combined.
You won't necessarily be prioritizing 21 specific 13, issues.
'14 MR. MICHELSON:
My own opinion--
15 CHAIRMAN SIESS:
You are working.on integration.
16 MR.-SZUKIEWICZ:
That's a possibility.
17 MR. MICHELSON: 41y own opinion on this particular 18 document is it ought to contain all the issues that people as 19 individuals have raised, and hopefully it does, and that.it be 20 viewed just as that, and that the real question of the 21 consensus of the ACRS should be at such time as the generic
.22 issue is brought to us for formal consideration.
23 I made very small comments along the way which I
()
'24 assume will be picked up.
The only one I wonder about perhaps 25 in being put into a letter is this question on the heating and HERITAGE REPORTING CORPORATION -- (202)628-4828
122
'l ventilating'.
That was going to be a comment in our A-17
~2 ~
letter,.but it never made it because they decided-to 3
abbreviate the A-17 letter.
I have a paragraph which'I can 4
propose as suitable for the letter,'if ycnt want to put a.
5 paragraph in our letter just to put it on the record so that--
'6 CHAIRMAN SIESS:
You have decided--will we write a 7
letter?
8' MR. MICHELSON:
If ycal do write a letter, this.ought 9
to be clarified.
Otherwise I guess it was clarified this 10 morning.
11 MR.lCASADA:.That related to safety related?
12 MR. MICHELSON:
Safety-related HVAC particularly.
l
)
13 That was going to be, I just thought--it is an important 14 issue, and it does expand the consideration.
I thought maybe 15 the Committee wanted to kick it around in a letter session, 16-but I have no problem just taking your word that it will be 17' included.
18 The document as a whole I think is, is great.
I 19 finally have seen all the bits and pieces.
At least it is 20 down in one place.
I'm sure there is bits and pieces missing, 21 but with the comments this morning, I think that it would be 22 new issues, not old issues.
23 I was just looking mostly to make sure all of our j) 24 old issues got in here, and I really believe that you have 25 done a fine jcb of pulling them all together.
It is, HERITAGE REPORTING CORPORATION -- (202)628-4888
123
/
1 certainly'it is worthwhile so that now I don't have to explain
'2
.to people what we'are talking about, just tell them to go'page 3
so and so of the document and read it and without continually.
4 trying to say what do you'mean?
'5 Well, you have done a fair job in here of trying to 6
pick up the issues, the point, and then try to explain a j
7 little bit of what it might means, but obviously it is not f
8 indicating any reocired action on it, but trying.to indicate' 9
what other people might have done on this, and what the 10 regulations might say, and I think that's great, and this.is a 11 fine document in that respect.
12 The real key question now becomes what are you going 13 to do with the document?
And we have to wait now to see how 14 the generic issue process picks this up and grinds it through, 15 and I understand that maybe within a year, we will be seeing 16 products of this document start to come out, so I have, I'm 17 quite pleased with the document.
I think that they did a. fine f
18 job on it.
19 CHAIRMAN SIESS:
Good.
Bill?
20 DR. KERR:
I don't disagree with any of the nice 1
21 things that have been said.
]
1 22 In the course of, in deciding what to do with this, 23 I would hope that the effort would be made to put this not h.
24' only in the context of existing regulations, but also in the 25 context of what we have learned about reliability theory, and i
HERITAGE REPORTING CORPORATION -- (202)628-4888 l
L l
124 1
1 not risk analysis so much as' reliability analysis.
2 This does two things as far as I am concerned, and I 3
think they are needed.
No.
1.,
it gives one some idea of the 4
likelihood that nome of these things will occur, and-the 5
second thing is that'it reduces the, these many times 6
artificial distinctions of safety and non-safety equipment.
7 What'we want-to find out is what is going to happen 8
to the plant, not whether it happens because of safety-related.
9 or non safety-related equipment, so I realize you can't maybe 10 do that entirely, but I would, I would recommend insofar as 11 one can, that prioritization or whatever the word is, take 12 that into account, maybe use that as the basis on which to do
)'
13 soFe of the prioritization.
14 CHAIRMAN SIESS:
Ivan?
15 DR. CATTON:
I really can't add anything to what 16 Carl said.
17 CHAIRMAN SIESS:
Okay.
Now there is two questions 18 then.
One is should we write a letter?
Do you want'a letter, 19 Warren?
20 MR. MINNERS:
No.
I don't think we particularly-21 need a letter, no.
22 CHAIRMAN SIESS:
You don't need it, so it is up to 23 us whether we want to write something.
Maybe I'll put the l
()
24 other question first.
We have got an hour and a half 25 scheduled tomorrow morning, tomorrow afternoon--Friday HERITAGE REPORTING CORPORATION -- (202)628-4888 l
___1_____
125
(
1 morning,'8:30, on this.
v 2
Do you really ?hink we need to bring the staff in h
3 here for an hour and a half for three people?
l l
4-MR. MICHELSON:
We have got three members that-5 aren't here.
I can't speak for the'three members that aren't' 6
here.
7 DR. KERR:
Especially since these are the seven most~
8 important members!
9 CHAIRMAN SIESS:
You know, we have gone through this 10 in kind of-detail.
11 MR. MICHELSON:
There is nothing new here.
12 CHAIRMAN SIESS:
An hour and a half, there,is not-
)
13 much they can do,-and I just don't see any need.
If-we.are 14 going to write a letter, we might want to say I will leave it 15 to the chairman.
Should we hear from the staff, should the 16 Full Committee hear from the staff on the subject, we are 17 going to write a letter.
Sometimes we have said yes,-
18 sometiwns no.
This isn't a licensing letter.
It i s
- r. letter 19 the staff doesn't really care whether they get.
20 DR. REMICK:
I would say let's gamble and not 21 require or ask the staff to.
In fact there will not be 22 objection.
If the other members do object, we might have to.
23 DR. KERR:
They have got this programmed into their
-()'
24 schedule.
They won't have anything to do.
25 DR. REMICK:
Will you write a subcommittee report?
l HERITAGE' REPORTING CORPORATION -- (202)628-4888 j
t 126 .1 . CHAIRMAN SI.ESS:- I will.make a report. :Since a. lot 2 of this came from Carl, he can comment, and I think that' 3' - Shewmon and Carroll and Lewis will go along with that. 4 Everybody got copies of everything. 5 MR. MICHELSON: There is one issue perhaps at' this 6 point we should talk about before concluding what to do, and 7 that is'this-question of our past letter, we didn't point out i 8 that we really think'part of this job was to go out and talk '9 to'other people and so forth. -10 'Do we'have any comment you want to make on that? 11' Clearly it was not done I think. 12 DR. KERR: I thought that we concluded we didn't get-( 13 a letter. 14 MR. MICHELSON: Pardon me. You're right. It didn't-15 get in the. letter. It got in the discussion. No, it 16 apparently didn't get in the letter, and I remember the 17 discussion real well. Dave Okrent was a portion of it,'but do- .18 we, do we feel that there should be an attempt to expand 19 beyond.what is in this document, or is there enough issues 20 here already? 21-CHAIRMAN SIESS: Never thought of that idea. I 22 would like to see the industry get involved in it more. That 23: would automatically do it. I don't know how to get that done. '()' 24 MR. WYLIE: I say I don't think you are going to get 25 it done. HERITAGE REPORTING CORPORATION -- (202)628-4888
127- '(. '1 'C.! AIRMAN SIESS:. They have got too many other th'.ngs 2 they are worried about. 3! MR. MICHELSON: I' don't have a strong-feeling on it 4 myself also. I think we have got enough'of this pulled 5 together here now to think abcut for sometirne. 6 CHAIRMAN SIESS: Now in view of the fact that the 7 staff seems to have demonstrated considerable ability to pick 8 up on comments that are made in subcommittee meetings, do you 9 think that we add anything to this by writing a letter,. 10 incorporate a few additional remarks? Since there is no real ~11-action by the staff at this point, they have got a list of 12 potential generic items to prioritize, and we have looked at ).
- 13 it and we have talked about it when they come up.
Is that 14 agreeable? 15 I will propose it to the Full Committee then 16 tomorrow, or Friday, whenever it comes up. You don't have to 17 show up if you don't want to. 18 Any other business, gentlemen? The meeting is 19 adjourned. 20 (Whereupon, at 11:45 a.m., the. meeting was 21 adjourned.) 22 23 () 24 25 HERITAGE REPORTING CORPORATION -- (202)628-4888
f 7 s-1 CERTIFICATE-2' 3 This is to certify that the attached proceedings-before the 4 United States Nuclear Megulatory Commission in the matter of: 5 Name: Advisory Committee cm Reactor Safeguards--Subcommittee on Generic Issues 6 7 Docket Number: 8 Place: Bethesda, Maryland 9 Date: July 12, 1989 10-were held as herein appears, and that this is the' original 11 transcript thereof for the file of the United States Nuclear 12 Regulatory Commission taken stenographically by me and, 13 thereafter reduced to typewriting by me or under the direction of the court reporting company, and that the transcript is a-14 15 true and accurate record of the foregoing proceedings. /S/ b_,Ik u ~s Y_ n. 16 7 17 (Signature typed): Catherine S. Boyd 18 Official Reporter 19 Heritage Reporting Corporation 20 21 22 23 24 25 Heritage Reporting Corporation (202) 628-4888 l l l E- - _ _ - - - _ - - _ - - - - _ - - - - J
,0 MULTIPLE SYSTEM RESPONSES PROGRAM (MSRP) PRESENTATION TO ACRS SUBCOMMITTEE ON GENERIC ITEMS l { July 12,1989 O I NRC STAFF CONTRACTOR STAFF { i l I A. SZUKIEWICZ, TASK MANAGER G. MURPHY, ORNL R. BAER, CHEF M. ROBERTS, JBF ASSOC. 4 ENGINEERING ISSUES BRANCH M. CASADA, JBF ASSOC. l D. THATCHER, SECTION LEADER I ENGINEERING ISSUES BRANCH 0 I l
- .:D BACKGROUND MSRP EVOLVED FROM:
o CONCERNS REGARDING SCOPE LIMITATIONS IMPOSED DURING RESOLUTION OF A NUMBER OF 'USIs: A-17 SYSTEMS INTERACTIONS O A-46 SEISMIC QUALIFICATION OF EQUIPMENT IN OPERATING NUCLEAR'PIANTS A-47 SAFETY IMPLICATIONS OF CONTROL SYSTEMS IN SYR NUCLEAR POWER PIANTS i o CONCERNS REGARDING PREVIOUS NRC PROGRAMS: ENVIRONMENTAL EQUIPMENT QUALIFICATION j SEISMIC-QUALIFICATION FIRE PROTECTION 1 O 4
.10 - MSRP OBJECTIVES o GATHER AND REVIEW INFORMATION ON USIs AND PREVIOUS PROGRAMS (i.e., EQ AND FIRE REVIEW) o DESCRIBE SPECIFIC CONCERNS: IDENTIFIED BY THE ACRS IDENTIFIED DURING REVIEW OF USIs o DEVELOP AND FURTHER DEFINE THOSE CONCERNS AS SPECIFIC P0TENTIAL SAFETY ISSUES o PROVIDE SUFFICIENT INFORMATION TO FURTHER DESCRIBE POTENTIAL SAFETY ISSUES IN ORDER THAT THE NRC CAN PRIORITIZE THESE ISSUES o PRIORITIZATION TO BE DONE BY NRC o
.O~ 1 SCHEDULE FOR MSRP o DRAFT REPORT SUBMITTED FOR ACRS REVIEW JUNE 1989 .o SOLICIT AND INCORPORATE ACRS COMMENTS C JULY / AUGUST 1989 ISSUE FINAL REPORT (NUREG/CR) o SEPTEMBER /0CTOBER 1989 o PRIORITIZE ISSUES AND ACRS REVIEW TBD seee ..e w,.. ,.. w.o )
-o
- U l
MSRP ISSUES o MSRP REPORT DESCRIBES 31 CONCERNS (SECTIONS 2 THROUGH 6) ~ o THESE CONCERNS RESULTED IN 21 DEFINED SAFETY ISSUES C IDENTIFIED FOR PRIORITIZATION (SECTION 7) o 10 0F THESE SAFETY ISSUES ARE ADDRESSED IN EXISTING PROGRAMS - TO BE CONFIRMED BY THE PRIORITIZATION PROCESS l C l i
- o. g 1
PRESENTATION OBJECTIVES o DESCRIBE THE SCOPE AND CONTENT OF THE MSRP g L o DISCUSS THE IDENTIFIED POTENTIit SAFETY ISSUES o 80IJCIT COMMENTS 1 C _--a--------_.__-...-m_
10 -COMMON CAUSE FAILURES RELATED TO HUMAN ERRORS (MSRP SECTION 7.3.2) POTENTIAL FOR OPERATOR ACTS OF OMISSION OR COMMISSION ON COMPONENTS AFFEGING REDUNDANT TRAINS; MANUFACTURING ERRORS IN COMPONENTS AFFEGING REDUNDANT TRAINS; AND INSTALLATION, MAINTENANCE, OR TESTING ERRORS REPEATED ON REDUNDANT TRAINS - NRC/ INDUSTRY ACTIONS: 10CFR21 REQUIRES MANUFACTURERS TO REPORT FABRICATION o OERRORS
- RG 1.123 PROVIDES GUIDANCE FOR COMPLYING WITH
- 10CFR50, APPENDIX. B WITH REGARDS TO CONTROL OF PROCUREMENT OF MANUFACTURED ITEMS RG 1.47 AND 1.97; NUREG-0660, 0737, 0700,1093, AND 0985 PROVIDE o
GUIDANCE FOR REDUCING OPERATOR ERRORS = IEB 85-03," MOTOR-OPERATED VALVE COMMON MODE FAILURES DURING 1 PLANT TRANSIENTS DUE TO IMPROPER SWITCH SETTING," ADDRESSES l DEFECTIVE PROCEDURES FOR SETTING SWITCHES AFTER TESTING OR MAINTENANCE - EXAMPLE OF CONTINUING STAFF INVOLVEMENT IN COMMON CAUSE PROBLEMS 'O 7
t-I O. ~ i 1 g [ ~ COMMON CAUSE FAILURES RELATED TO HUMAN ERRORS (CONT.)- (MSRP SECTION 7.3.2) l lNRC/ INDUSTRY ACTIONS (CONT.h - o INPO'S HUMAN ' PERFORMANCE EVALUATION SYSTEM IS USED FOR EVALUATING PERFORMANCE IN THE. AREAS OF OPERATIONS, . : INSTALLATION, MAINTENANCE, AND TESTING ..o NUREG-0985L ALSO ADDRESSES INSTALLATION, MAINTENANCE, AND s TESTING ERRORS RELATED TO. TRAINING, PROCEDURES, STAFFING, AND QUALIFICATIONS STATUS: o.. CONCERNS ARE CONSIDERED BY EXISTING REGULATIONS, GUIDANCE, .'AND PROGRAMS
- o. TO BE CONFIRMED BY THE PRIORITIZATION PROCESS 8
~ $PENDENCIES BETWEEN SAFETY-AND NON-SAFETY-RELATED SYSTEMS (MSRP SECTION 7.3.3)
- POTENTIAL FOR MULTIPLE SIMULTANEOUS FAILURES IN NON-SAFETY-RELATED CONTROL SYSTEMS TO HAVE AN ADVERSE IMPACT ON SAFETY-RELATED PROTECTION SYSTEMS NRC/ INDUSTRY. ACTIONS:
. GDC 22 REQUIRES INDEPENDENCE OF REDUNDANT CHANNELS OF THE PROTECTION SYSTEM + GDC 24 REQUIRES SEPARATIOM OF CONTROL AND PROTECTION SYSTEMS . SRP 7.1, 7.2, 71. 7.7, IEEE STDs 279,379, AND 384 PROVIDE GUIDANCE FOR SATISFYING THE GDC. THEY DO NOT SPECIFICALLY ADDRESS MULTIPLE FAILURES OF CONTROL SYSTEMS
- RG 1.153 AND IEEE STD 603-1980 PROVIDE GUIDANCE FOR PLANTS DOCKETED AFTER NOVEMBER 1985
. IEN 79-22, 79-29, AND 84-86 ADDRESS EVENTS THAT HAVE OCCURRED THAT ARE RELATED TO THIS ISSUE STATUS: . ISSUE APPEARS TO BE ADDRESSED IN REGULATIONS AND GUIDANCE. HOWEVER, PROPER LICENSEE IMPLEMENTATION IS REQUIRED TO ENSURE ADEQUATE PROTECTION gTO BE PRIORITIZED 9
k ) FAILURE MODES OF DIGITAL COMPUTER-CONTROL' SYSTEMS- _y M (MSRP SECTION 7.3.4) oJPOTENTIAL FOR ADVERSE INTERACTIONS BETWEEN COMPUTERIZED j ' CONTROL SYSTEMS AND SAFETY-RELATED PROTECTION SYSTEMS -o USE OF DIGITAL COMPUTER CONTROL SYSTEMS FOR SAFETY-RELATED PURPOSES l n NRC/ INDUSTRY ACTIONS: + GDC 22 REQUIRES INDEPENDENCE OF REDUNDANT CHANNELS OF THE. 4 . PROTECTION SYSTEM -o GDC--24. REQUIRES SEPARATION OF CONTROL. AND PROTECTION l ' SYSTEMS j . OGI A-19," DIGITAL COMPUTER PROTECTION SYSTEMS"IS INVESTIGATING
- THE USE OF DIGITAL COMPUTERS IN NUCLEAR POWER PLANTS' SAFETY-RELATED SYSTEMS - TO BE PRIORITIZED
. ANSI /IEEE-ANS-7-4.3.2-1982, " APPLICATION CRITERIA-FOR PROGRAMMABLE o DIGITAL COMPUTER SYSTEMS IN SAFETY SYSTEMS OF NUCLEAR POWER GENERATING STATIONS," AND RG 1.152 (ACCEPTS ANSI /IEEE-ANS-7-4.3.2-1982) PROVIDE GUIDANCE FOR ADDRESSING THE ISSUE IN GI A-19 ~ STATUS: a FIRST ISSUE ALREADY ADDRESSED BY SEPARATION AND INDEPENDENCE CRITERIA a IT APPEARS THAT GI A-19 WILL ADDRESS THE SECOND ISSUE OTO'BE CONFIRMED BY THE PRIORITIZATION PROCESS 10
.,)'. p L l 1 p ll SPECIFIC SCENARIO NOT CONSIDERED IN USI A ' -(MSRP SECTION 7.3.5) - oISCRAM WITHOUT TURBINE TRIP INCLUDING RETURN TO CRITICALITY - RESULTING FROM OVERCOOLING THE PRIMARY SYSTEM ' 11RC/ INDUSTRY ACTIONS: ~W+ GI
- 144,
" SCRAM - WITHOUT A TURBINE / GENERATOR TRIP," WILL - INVESTIGATE-THIS ISSUE - TO BE PRIORITI7ED-STATUS: o ;IT APPEARS THAT GI 144 WILL ADDRESS THIS ISSUE -a.TO BE CONFIRMED BY THE PRIORITIZATION PROCESS O 11 a i
O ~ SPECIFIC SCENA.RIO NOT CONSIDERED IN USI A-47 (CONT.) (MSRP SECTION 7.3.5) l STEAM GENERATOR OVERFILL LEADING TO A MAIN STEAM LINE BREAK L o-AND A STEAM GENERATOR TUBE RUPTURE THAT WOULD INVOLVE THE BLOWDOWN OF MORE THAN ONE STEAM GENERATOR NRC/ INDUSTRY ACTIONS: orTHREE' SEPARATE USIs HAVE INVESTIGATED TUBE RUPTURES USI A-3, " WESTINGHOUSE STEAM GENERATOR TUBE INTEGRITY" USI A-4, "B&W STEAM GENERATOR TUBE INTEGRITY" O - USI A-5, "CE STEAM GENERATOR TUBE INTEGRITY"
- NUREG-0844 DESCRIBES AN INTEGRATED NRC PROGRAM TO RESOLVE THESE THREE ISSUES o' GI 135, " STEAM GENERATOR AND STEAM LINE OVERFILL,"
.WILL - ADDRESS THE POTENTIAL EFFECI'S OF STEAM GENERATOR OVERFILL ON SECONDARY SYSTEM COMPONENTS STATUS: IT ' APPEARS THAT USIs A-3, A-4, A-5, AND GI 135 WILL ADDRESS THIS ISSUE o TO BE CONFIRMED BY THE PRIORITI7ATION PROCESS O 12
~IO DEGRADATION OF HVAC EQUIPMENT ON CONTROL AND PROTECTION SYSTEMS ) (MSRP SECTION 7.3.6) i
- HVAC DEGRADATION OR FAILURE COULD CAUSE MULTIPLE FAILURES
.IN NON-SAFETY-RELATED CONTROL SYSTEMS THAT COULD IMPACT SAFETY-RELATED SYSTEMS H 'NRC/ INDUSTRY ACTIONS: GDC 24. REQUIRES THAT A SINGLE CONTROL SYSTEM COMPONENT-o FAILURE NOT COMPROMISE THE PROTECTION SYSTEM O SRP 9.4.1, 9.4.2, 9.4.3, 9.4.4, AND 9.4.5 - PROVIDE GUIDANCE FOR' THE DESIGN OF HVAC SYSTEMS THAT PROVIDE ENVIRONMENTAL CONTROL FOR AREAS CONTAINING SAFETY-RELATED ' COMPONENTS -- DOES NOT ADDRESS HVAC SYSTEMS FOR AREAS CONTAINING NON-SAFETY-RELATED COMPONENTS STATUS:
- POTENTIAL DEGRADATION EFFECTS NOT SPECIFICALLY ADDRESSED
-BY EXISTING PROGRAMS 'o TO BE PRIORITIZED 0 13
s FAILURE MODES RES'ULTING FROM DEGRADED-t ' ELECTRIC POWER SOURCES. i (MSRP SECTION 7.3.7) j l
- : EFFECTS OF ELECTRICAL SYSTEM DEGRADATION (i.e., UNDERVOLTAGE-AND OVERVOLTAGE) MAY NOT HAVE BEEN ADEQUATELY EVALUATED l
NRC/ INDUSTRY ACTIONS: 6 GDC 17 AND 18 PROVIDE REQUIREMENTS FOR THE DESIGN OF ELECTRIC POWER SYSTEMS SRP 8.1, 8.2, 8.3.1, 8.3.2, AND BTP PSB-1 PROVIDE GUIDANCE' FOR o SATISFYING THE GDC O GDC AND'SRP DO NOT SPECIFICALLY REQUIRE UNDERVOLTAGE OR OVERVOLTAGE OF ELECTRIC POWER SYSTEMS TO BE INVESTIGATED-
- IEB 79-27, " LOSS OF NON-CLASS-IE INSTRUMENTATION AND CONTROL POWER SYSTEM BUS DURING OPERATION," REQUIRED LICENSEES TO REVIEW LOSS OF POWER EVENTS FOR THEIR PLANTS r
IEN 89-16 DESCRIBES THE POTENTIAL FOR AN UNDERVOLTAGE EVENT o IN A PLANT'S DC POWLR SYSTEM THAT COULD LEAD TO A TOTAL LOSS OF AC POWER STATUS:
- NOT SPECIFICALLY ADDRESSED BY EXISTING PROGRAMS
- TO BE PRIORITIZED O
u 14 _-_:_-__-L-__---___________:____
v LO FAILURE MODES RESULTING FROM DEGRADED COMPRESSED AIR SYSTEMS (MSRP SECTION 7.3.8) o EFFECTS OF AIR SYSTEM DEGRADATION (i.e., GRADUAL LOSS OF AIR PRESSURE, UNDERPRESSURIZATION, AND OVERPRESSURIZATION) MAY l L NOT HAVE BEEN ADEQUATELY EVALUATED l I l NRC/ INDUSTRY ACTIONS: i o -SRP 9.3.1 PROVIDES GUIDANCE FOR THE DESIGN OF COMPRESSED AIR' SYSTEMS ORG 1.68.3 PROVIDES GUIDANCE FOR TESTING OF COMPRESSED; AIR SYSTEMS. ' ADDRESSES TOTAL LOSS OF AIR PRESSURE BOTH SUDDEN' AND' GRADUAL I o GI 43, " RELIABILITY OF AIR SYSTEMS," PROVIDED~ A LIMITED .i EVALUATION OF GRADUAL LOSS OF AIR PRESSURE AND o 1 UNDERPRESSURIZATION - SUGGESTED THAT IT BE PRIORITIZED j SEPARATELY o. THE GI 43 GENERIC LETTER (GL 88-14), ONLY ADDRESSED TOTAL LOSS l OF AIR SYSTEM PRESSURE i -
- IEN 80-40 AND 88-24 DESCRIBE EVENTS THAT CAUSED SAFETY-RELATED EQUIPMENT TO FAIL 4
O l i 15 1 m--_-_----_-.__-._._--__
g ~,3 r,. D l l FAILURE MODES RESULTING FROM DEGIMDED ~ COMPRESSED AIR. SYSTEMS '(CONT.) -(MSRP SECTION 7.3.8) ) l NRC/ INDUSTRY ACTIONS (CONT.h p i.DIEN-82-25 DESCRIBES AN EVENT IN WHICH SAFETY-RELATED VALVES- ] .DID NOT GO TO THEIR FAIL-SAFE POSITION UPON GRADUAL LOSS OF ~
- AIR PRESSURE Q NUREG-1275 REPORTS- - ON - AN. AEOD REVIEW. 'OF OPERATING
- EXPERIENCE RELATED TO AIR SYSTEM PROBLEMS
.l l l STATUS: i A GL-88-14 ADDRESSES THE ASPECT OF TOTAL LOSS OF AIR SYSTEM .)
- OVERPRESSURIZATION AND GRADUAL-LOSS OF AIR PRESSURE ARE NOT ADDRESSED o.TO BE PRIORITIZED O
16 _2.___ i
- o;
-k -POTENTIAL EFFECTS OF UNTIMELY COMPONENT OPERATION. (MSRP SECTION 7.3.9) o' THE EFFECTS OF'A COMPONENT'S FAILURE ' OR INADVERTENT
- ACTUATION AT AN - UNANTICIPATED TIME. MAY NOT HAVE BEEN CONSIDERED -
NRC/ INDUSTRY ACTIONS: o GDCs ESTABLISH MINIMUM REQUIREMENTS FOR DESIL N, FABRICATION,- CONSTRUCTION,- TESTING, AND PERFORMANCE FOR STRUCTURES,- SYSTEMS, AND COMPONENTS IMPORTANT TO SAFETY O " LESSONS LEARNED". PROGRAMS SHOULD IDENTIFY A - GENERIC' PROBLEM IN THIS AREA THROUGH: NRC REVIEW OF LERs UTILITY OPERATING EXPERIENCE REVIEWS (POST TMI) STATUS: o-TYPICALLY FAILURE ANALYSES TEND TO ASSUME EITHER WORKING OR FAILED CONDITIONS. THEY DO NOT ADDRESS ALL TIME-ORDERED SEQUENCES DURING WHICH FAILURE OR INADVERTENT ACTUATION MAY OCCUR TO BE PRIORITIZED e 1 LO l I 17 l l l
a y, 4,- h;' PR' PAGATION.OF HARSH ENVIRONMENTS ' O (MSRP SECTION 7.3.10); oEA* HARSH ENVIRONMENT MAY PROPAGATE BY SOME UNKNOWN-OR-UNRECOGNIZED PATHWAY INTO ANOTHER ZONE. l i q , :NRC/ INDUSTRY ACTIONS: .l 10CFR50.49? SPECIFIES -THAT ELECTRIC EQUIPMENT IMPORTANT TOL e SAFETY MUST BE QUALIFIED BY TEST TO SURVIVE POTENTIAL HARSH ENVIRONMENTS - I - *.SRP ;3.11, RG.1.89, ANDL IEEE STD 323-1974 PROVIDE GUIDANCE-ON-l O. QUALIFYING EQUIPMENT IMPORTANT TO SAFETY FOR POTENTIAL LHARSH ENVIRONMENTS
- THE IPE (GENERIC LETTER-88-20) MAY INCLUDE CONSIDERATION OF
- THIS : ISSUE: STATUS: FISSUE ' APPEARS TO BE ADDRESSED GENERALLY IN THE REGULATIONS AND GUIDANCE. HOWEVER, PROPER LICENSEE EVALUATION 'OF
- PROPAGATION PATHWAYS' IS REQUIRED TO ENSURE ADEQUATE
- PROTECTION
.
- TO BE PRIORITIZED L
O 18
[)- HEAT, SMOKE, AND WATER PROPAGATION EFFECTS RESULTING FROM FIRES (MSRP SECTION.7.3.11.) o MULTIPLE TRAINS OF-SAFETY-RELATED EQUIPMENT.' COULD'. BE-AFFEGED BY. HEAT, SMOKE, AND. WATER PROPAGATION EFFECTS RESULTING FROM FIRES NRC/ INDUSTRY ACTIONS: GDC 3,10CFR50.48,- AND 10CFR50, APPENDIX R ESTABLISH REQUIREMENTS C 'FOR PROTECTION OF REDUNDANT TRAINS OF EQUIPMENT REQUIRED TO ACHIEVE PLANT -SHUTDOWN-AND FOR ESTABLISHING A FIRE ~ PROTEGION PLAN SRP 9.5.1, BTP CMEB 9.5-1, GL 81-12, " FIRE PROTEGION RULE," AND GL' 86-10, " IMPLEMENTATION.OF FIRE PROTEGION REQUIREMENTS,"- PROVIDE GUIDANCE FOR SATISFYING THE REGULATIONS.. SRP 9.5.1 SPECIFIES THAT SAFETY-RELATED EQUIPMENT SHOULD BE PROTEGED. FROM THE EFFEGS OF FIRE, HEAT, SMOKE, AND WATER EXPOSURE STATUS: ISSUE APPEARS TO BE ADDRESSED GENERALLY IN THE REGULATIONS a AND GUIDANCE. HOWEVER, PROPER LICENSEE EVALUATION OF ' PROPAGATION PATHWAYS IS REQUIRED TO ENSURE ADEQUATE PROTEGION TO BE PRIORIT17ED 19
.z. h SYNERGISTIC EFFECTS OF HARSH ENVIRONMENTAL CONDITIONS (MSRP SECTION 7.3.12) o' SYNERGISTIC EFFECTS OF HARSH ENVIRONMENTAL CONDITIONS MAY NOT NAVE BEEN ADEQUATELY ADDRESSED BY THE LICENSEES NRC/ INDUSTRY ACTIONS: o GDC 4 AND 10CFR50.49 ESTABLISH THE REQUIREMENTS FOR O, ENVIRONMENTAL QUALIFICATION OF EQUIPMENT AND SPECI INCLUDE THE CONSIDERATION OF SYNERGISTIC EFFECTS
- o. SRP 3.11, RG 1.89, IEEE STD-323, AND NUREG-0588 PROVIDE GUIDANCE FOR CONDUCTING ENVIRONMENTAL QUALIFICATION REQUIRE THAT SYNERGISTIC EFFECTS THAT HAVE BEEN IDENTIFIED MUST BE INCLUDED IN THE ANALYSIS NO PRESCRIPTIVE GUIDANCE IS PROVIDED FOR HOW THESE SYNERGISTIC EFFECTS SHOULD BE ANALYZED O
20
D: p-r l 1' . SYNERGISTIC EFFECTS OF HARSH ENVIRONMENTAL CONDITIONS (CONT.) (MSRP SECTION 7.3.12). l NRC/ INDUSTRY ' ACTIONS (CONT.); NUREG/CR-0275, NUREG/CR-3538, NUREG/CR-3588, NUREG/CR-3863, o NUREG/CR-4301, NUREG/CR-4536, NUREG/CR-5313, AND EPRI NP-1558 DESCRIBE EFFORTS: TO STUDY THE EFFECTS OF ENVIRONMENTAL SYNERGISMS ON VARIOUS MATERIALS AND COMPONENTS . STATUS:
- THE REGULATIONS REQUIRE THAT SYNERGISTIC EFFECTS BE CONSIDERED AND ADDRESSED WHENEVER POSSIBLE DURING TESTING
= THERE IS LITFLE GUIDANCE AVAILABLE FOR PERFORMING SUCH ANALYSES OR TESTS
- TO BE PRIORITIZED O.
21
l ENVIRONMENTAL QUALIFICATION OF SEALS, GASKETS, PACKING, AND - LUBRICATING FLUIDS ASSOCIATED WITH MECHANICAL EQUIPMENT-(MSRP SECTION 7.3.13)
- POTENTIAL DETRIMENTAL EFFECTS OF HARSH ENVIRONMENTAL CONDITIONS ON SUBCOMPONENTS OF MECHANICA'L EQUIPMENT (i.e.,.
SEAI.S, GASKETS, PACKING, AND LUBRICATING FLUIDS) NRC/ INDUSTRY ACTIONS: ^ GDC 4.PROVIDES GENERAL REQUIREMENTS FOR ENVIRONMENTAL a. QUALIFICATION FOR-STRUCFURES, SYSTEMS, AND COMPONENTS O IMPORTANT TO SAFETY a SRP 3.11 IEEE STD 323-1974, AND NUREG-0588 PROVIDE GUIDANCE FOR CONDUCTING ENVIRONMENTAL QUALIFICATION IEN 79-35,84-12,85-08, AND 87-51 REPORTED EVENTS INVOLVING FAILURES o OF THESE TYPES OF EQUIPMENT STATUS:
- EQ HAS CONCENTRATED ON ELECTRICAL EQUIPMENT. MECHANICAL EQUIPMENT WITHOUT ELECFRICAL COMPONENTS HAS RECEIVED LESS ATTENTION
- TO.BE PRIORITIZED I
O 22
l {} FIRE SUPPRESSION SYSTEM ACTUATIONS ON SAFETY-AND NON-SAFETY-RELATED EQUIPMENT (MSRP SECTION 7.3.14) POTENTIAL ADVERSE EFFECT ON SAFETY-RELATED COMPONENTS o EITHER THROUGH DIRECT CONTACT WITH SUPPRESSION AGENTS OR THROUGH INDIRECT INTERACTIONS WITH NON-SAFETY-RELATED COMPONENTS THAT ARE AFFECTED BY FIRE SUPPRESSION SYSTEM ACTUATION EVENTS NRC/ INDUSTRY ACTIONS: GDC 3 AND 10CFR50, APPENDIX R SET FORTH THE REQUIREMENTS FOR o THE PROTECTION OF SAFETY-RELATED EQUIPMENT FROM O INADVERTENT OPERAT1ON OF FIRE SUPPRESSION SYSTEMS GI 57, " EFFECTS OF FIRE PROTECTION SYSTEM ACTUATION ON SAFETY-o RELATED EQUIPMENT," ADDRESSES THIS ISSUE. ORIGINALLY ASSIGNED A MEDIUM PRIORITY, GI 57 IS UNDER CONSIDERATION TO BE MADE A HIGH PRIORITY ISSUE IEN 83-41, AND 87-14 DESCRIBE TWO EVENTS WHERE ACTUATION OF o FIRE SUPPRESSION SYSTEMS HAD AN ADVERSE EFFECT ON SAFETY-RELATED EQUIPMENT STATUS: IT APPEARS THAT GI 57 WILL FULLY ADDRESS THIS CONCERN o TO BE CONFIRMED BY THE PRIORITIZATION PROCESS -h j b 8
x t; p . FLOODING AND/OR MOISTURE INTRUSION ON q ~ . SAFETY AND NON-SAFETY-RELATED EQUIPMENT (MSRP SECTION 7.3.15)
- ' POTENTIAL FOR FLOODING OR MOISTURE INTRUSION TO EITHER.
DIRECTLY OR INDIRECFLY -AFFECF MULTIPLE TRAINS OF SAFETY-RELATED EQUIPMENT NRC/ INDUSTRY ACTIONS:
- a. GDC 2 AND 4 REQUIRE THAT SAFETY-RELATED EQUIPMENT BE iPROTECTED FROM BOTH INTERNALLY-INITIATED AND EXTERNALLY-INITIATED FLOODS o ' SRP 3.4.1,~ 3.6.1, 9.3.3,10.4.5, BTP MEB 3-1, AND RG 1.11 PROVIDE GUIDANCE-FOR DESIGNING 'AND ANALYZING A PLANT FOR FLOOD PROTECTION o - IEN 84157 REPORTED ON OPERATING EXPERIENCE RELATED: TO MOISTURE INTRUSION IN SAFETY-RELATED ELECTRICAL EQUIPMENT THE IPE REQUIRES THAT PLANTS BE EXAMINED FOR VULNERABILITIES o
TO INTERNAL FLOODING EVENTS THE IPE FOR EXTERNAL EVENTS WILL ADDRESS EXTERNAL FLOODING o EVENTS STATUS: INTERNAL FLOODING APPEARS TO BE SPECIFICALLY ADDRESSED BY IPE f TO BE CONFIRMED BY THE PRIORITIZATION PROCESS 24
g_ I-SEISMICAL'LY INDUCIT PATIAL AND FUNCTIONAL INTERAGIONS. (in3RP SECTION 7.3.16) J r POTENTIAL FOR SEISMIC EVENTS TO FAIL MULTIPLE TRAINS OF SAFETY-- RELATED EQUIPMENT THROUGH SPATIAL AND FUNGIONAL -INTERAGIONS L ] l. 1 1 L NRC/ INDUSTRY ACTIONS:
- DGDC 2
REQUIRES STRUGURES,'
- SYSTEMS, AND
' COMPONENTS IMPORTANT TO: SAFETY BE ABLE TO WITHSTAND THE EFFEGSi OF i EARTHQ'UAKES . *- SRP 3.7.2,. 3.7.3 = AND RG.1.29 PROVIDE GUIDANCE FOR' DESIGNING SYSTEMS AND SUBSYSTEMS SUCH THAT THEY COMPLY WITH THE GDC a THE USI A-46 GENERIC LETTER (GL 87-02) REQUESTED THAT LICENSEES VERIFY THE SEISMIC ADEQUACY OF EQUIPMENT BY COMPARISON WITH --AN EXPERIENCE DATA BASE i STATUS:
- - ADEQUATE GUIDANCE FOR MEDIUM AND LARGE SIZE PIPES DOES NOT APPEAR TO SPECIFICALLY ADDRESS FAILURES OF CERTAIN o
SMALL' PIPING AND THE POTENTIAL FOR ASSOCIATED SYSTEM . INTERACTIONS
- LTO BE PRIORITIZED i
O u L_-__---___.-
N 1 ' 5l ] o 1 SEISMICALLY INDUCED FIRES (MSRP SECTION 7.3.17)
- l POTENTIAL FOR' SEISMICALLY INDUCED FIRES TO' CAUSE MULTIPLE' FAILURES OF SAFETY-RELATED EQUIPMENT H
NRC/ INDUSTRY ACTIONS: .o GDC' 2-AND 3 REQUIRE THAT SAFETY-RELATED EQUIPMENT BE PROTECTED FROM THE EFFECTS OF EARTHQUAKES AND FIRES-Q NUREGICR-5042, EVALUATION OF ' EXTERNAL' HAZARDS - TO ' NUCLEAR. ' PLANTS IN THE UNITED STATES,-INVESTIGATED THE POTENTIAL FOR .HAVING SEISMICALLY INDUCED FIRES STATUS:
- THE.NRC ' STAFF HAS SPECIFICALLY STATED (BTP CMEB 9.5-1) THAT-ONLY LIMITED FIRE PROTECTION IS REQUIRED IN POST EARTHQUAKE SITUATIONS
- L TO BE PRIORITIZED i
O
l ;. L: w L.[ ',. g u SEISMICALLY INDUCED FIRE SUPPRESSION SYSTEM ACTUATIONS (MSRP SECTION 7.3.18) e - POTENTIAL FOR SEISMICALLY INDUCED FIRE SUPPRESSION ACTUATION TO CAUSE MULTIPLE FAILURES OF SAFETY-RELATED EQUIPMENT. BTRC/ INDUSTRY ACTIONS: l GDC 3 STATES.THAT SAFETY-RELATED EQUIPMENT MUST BE ABLE TO o. I SURVIVE AN SSE-i 10CFR50, APPENDIX R STATES THAT DEDICATED SHUTDOWN CAPABILITY o iMUST BE PROVIDED WHERE REDUNDANT SYSTEMS MAY BE SUBJECTED Q TO DAMAGE FROM. INADVERTENT FIRE SUPPRESSION SYSTEM ACTUATION
- GI 57," EFFECTS OF FIRE PROTECTION SYSTEM ACTUATION ON SAFETY--
RELATED EQUIPMENT," WILL INVESTIGATE ALL AVAILABLE DATA ASSOCIATED.WITH-COMMON CAUSE INITIATORS OF. MULTIPLE FIRE PROTECTION SYSTEM ACTUATIONS, INCLUDING EARTHQUAKES STATUS:
- IT APPEARS THAT GI 57 WILL INCLUDE CONSIDERATION OF
. SEISMICALLY INDUCED FIRE SUPPRESSION SYSTEM ACTUATION
- TO BE CONFIRMED BY THE PRIORITIZATION PROCESS i
O 1 27 =---___-__-___-______-________:--_.
\\ \\:.. ..h... -SEISMICALLY INDUCED FLOODING -(MSRP SECTION 7.3.19)
- o ! OTENTIAL FOR SEISMICALLY INDUCED FLOODING EVENT TO CAUSE P
MULTIPLE FAILURES OF SAFETY-RELATED EQUIPMENT NRC/ INDUSTRY ACTIONS:
- o. GDC 2 AND 4 REQUIRE PROTECTION OF SAFETY-RELATED EQUIPMENT
'FROM THE EFFECTS OF SEISMIC AND FLOODING EVENTS INCLUDING -LOCAs SRP 34.1 PROVIDES GUIDANCE ~ FOR EVALUATING PLANT FLOOD ' o. NUREG/CR-4776 INVESTIGATED THE RESPONSE OF SEISMIC CATEGORY I TANKS.TO EARTHQUAKE EXCITATION o IPE FOR EXTERNAL EVENTS WILL INVESTIGATE - PLANT VULNERABILITIES ' TO ALL ' EXTERNAL
- EVENTS, INCLUDING EARTHQUAKES STATUS:
- NOT SPECIFICALLY ADDRESSED BY EXISTING PROGRAMS o.-TO BE ADDRESSED IN IPE FOR EXTERNAL EVENTS
- TO BE CONFIRMED BY THE PRIORITIZATION PROCESS O
28
.g. l. SEISMICALLY INDUCED RELAY CHATTER' (MSRP SECTION 7.3.20)
- o; POTENTIAL FOR SEISMICALLY INDUCED ' RELAY CHATTER TO CAUSE FAILURE OF EQUIPMENT REQUIRED DURING AND AFTER A SEISMIC'
-EVENT NRC/ INDUSTRY ACTIONS: o GDC 2 REQUIRES PROTECTION OF SAFETY-RELATED EQUIPMENT FROM THE EFFECTS OF SEISMIC EVENTS o-SRP 3.10, RG 1.100,' AND IEEE STD-344-1975 PROVIDE GUIDANCE FOR THE SEISMIC QUALIFICATION OF EQUIPMENT IMPORTANT TO SAFETY. THE USI A-46 GENERIC LETTER-(GL 87-02) INCLUDED CONSIDERATION ' .OF SEISMICALLY INDUCED RELAY CHATTER o - NUREG/CR-4910 INVESTIGATED RELAY. CHATTER AFTER A LARGE : EARTHQUAKE o -IPE FOR EXTERNAL EVENTS WILL ALSO ADDRESS THIS ISSUE l STATUS: A-46 RESOLUTION (GL 87-02) SPECIFICALLY ADDRESSED THIS ISSUE o RELAY CHATFER WILL BE ADDRESSED BY THE IPE FOR EXTERNAL o EVENTS TO.BE CONFIRMED BY THE PRIORITIZATION PROCESS o O 29
a { ' EVALUATION OF EARTHQUAKE MAGNITUDES GREATER THAN THE SSE (MSRP SECTION 7.3.21) ADEQUATE SEISMIC MARGINS MAY NOT HAVE BEEN INCLUDED IN THE o DESIGN OF SOME SAFETY-RELATED EQUIPMENT 'NRC/ INDUSTRY ACTIONS: e NUREG 1147, SEISMIC SAFETYRESEARCH PROGRAM PLAN, INCLUDES THE. .O. SEISMIC DESIGN MARGINS PROGRAM, WHICH WILL INVESTIGATE THE ADEQUACY OF CURRENT SEISMIC DESIGN MARGINS ~ STATUS: o APPEARS TO BE ADDRESSED IN THE SEISMIC DESIGN MARGINS . PROGRAM TO BE CONFIRMED BY THE PRIORITI7ATION PROCESS o O
r ' EFFECTS OF HYDROGEN LINE RUPTURE (MSRP SECTION 7.3.22) +1 HYDROGEN LINE RUPTURE WITH SUBSEQUENT FIRE-. AND/OR' L JXPL.OSION COULD DAMAGE MULTIPLE TRAINS OF SAFETY-RELATED EQUIPMENT 'NRC/ INDUSTRY ACFIONS:
- e. BTP CMEB 9.5-1 STATES THAT HYDROGEN LINES IN SAFETY-RELATED AREAS SHOULD BE DESIGNED TO PREVENT HYDROGEN CONCENTRATIONS FROM EXCEEDING 50 %
OF THE LOWER FLAMMABILITY LIMIT IN THE EVENT OF A HYDROGEN LINE BREAK GI 106," PIPING AND THE USE OF HIGHLY COMBUSTIBLE GASES IN VITAL. e AREAS," ADDRESSES PROTECTION OF SAFETY.RELATED EQUIPMENT FROM THE EFFECTS OF HYDROGEN LINE BREAKS - MEDIUM PRIORITY
- NUREG/CR-3551 INVESTIGATED THE SAFETY IMPLICATIONS
- OF PRESSURIZED GAS SYSTEMS IN NUCLEAR POWER PLANTS STATUS: IT APPEARS THAT GI 106 WILL FULLY ADDRESS THIS CONCERN -o-
- TO BE CONFIRMED BY THE PRIORITIZATION PROCESS o
I 31
[ LACK OF SPECIFIC ACTION RELATED TO SYSTEMS INTERACTION 'q (MSRP SECTION 7.3.1) V LACK OF SPECIFIC REQUIREMENTS FOR LICENSEES TO RESPOND TO o SPECIFIC SYSTEMS INTERACTION (SI) CONCERNS IDENTIFIED IN USI A-17 LACK OF SPECIFIC ACTIONS OR REQUIREMENTS IMPOSED ON LICENSEES o BY THE NRC FOR PERFORMING SPATIAL SI STUDIES LACK OF DEDICATED INTERDISCIPLINARY GROUPS FOR IDENTIFYING o PLANT SPECIFIC sis NRC/ INDUSTRY ACTIONS: MSRP TO IDENTIFY SPECIFIC ISSUES o GENERIC AND PLANT SPECIFIC sis CAN BE IDENTIFIED BY CURRENT o O"tESSONS tEARNED PROGRAMS SuCH AS: INPO OPERATING EXPERIENCE PROGRAMS NRC REVIEW OF LERS UTILITY OPERATING EXPERIENCE REVIEWS (POST TMI) o THE IPE GENERIC LETTER (GL 88-20) REQUESTS LICENSEES TO IDENTIFY PLANT SPECIFIC VULNERABILITIES TO SEVERE ACCIDENTS STATUS: GENERAL CONCERNS ARE CONSIDERED IN NRC AND INDUSTRY o PROGRAMS SPECIFIC MSRP ISSUES AS DEFINED AND PRIORITIZED o O l v l 32 ____-___________________-_____L}}