ML19345H188
| ML19345H188 | |
| Person / Time | |
|---|---|
| Issue date: | 04/23/1981 |
| From: | NRC COMMISSION (OCM) |
| To: | |
| Shared Package | |
| ML19345H189 | List: |
| References | |
| FRN-45FR65466, REF-10CFR9.7, RULE-PR-50 SECY-81-245, NUDOCS 8105010186 | |
| Download: ML19345H188 (98) | |
Text
- -.-
s'/
'/,,,
dh,, ' 2).UO.?
. ~ '. : :
NCCLEAR REGUI.ATOR'? CCMMISSICN c,, ' is i z
' s.
,/,',
~,.
'% f', 's
(
COMMISSION MEETING M -
3 tta Mattar of:
BRIEFING ON EFFECTIVE INTERIM AMENDtEENTS l
TO 10 CFR 50 ON HYDROGEN CONTROL AND
- -.T' i
CERTAIN DEGRADED CORE CONSIDERATIONS
!!!!? :
i I
a l
=
(
~
DATE:
Aoril 23, 1981 PAGES:
1 - 95: -.
l L
AO:
Washincton, D.
C.
E I
W
/
p N
9 qs % wr*
9
\\r /
cn 11DE%T
@ M I.T O
\\
f.
400 71:gir.ia Ave., 5.W. Washing :=, D. C.
20024 Talachc:a: (202) 554-2245 8105 010 lfb i
)
f
~
1 1
UNITED STATES OF AMERICA 2
NUCLEAR REGULATORY COMMISSION 3
BRIEFING ON EFFECTIVE INTERIM AMENDMENTS TO 10 CFR 50 ON HYDROGEN CONTROL AND CESTAIN 4
DEGRADED CORE CONSIDERATIONS 5
6 Boom 1130, 7
1717 H Street, N.W.
Washington, D. C.
8 i-Thursday, April 23, 1981 9
10 The Commission met at 10:10 p.n.,
pursuant to 11 notice, Joseph Hendrie, Chairman of the Coarission, 12 presiding.
13 Commissioners present:
Chairman Joseph Hendrie, 14 Commissioner John Ahearne, Commissioner Victor-Gilinsky, and 15 Commissioner Peter Bradford.
16 Present for the N?C Secretary's Offices 17 S. Chilk 18 Present for the Offire of the Executive Directo r for Ocerations:
19 E. Kevin Cornall 20 Present for the NRC Office of General Counsel 21 L. BICKWIT, Esq.
22 23 24 25 ALCERSoN REPoATING COMP ANY,INC.
2 1_ _.__ Present f or NBC Office of Vuelear Peactor Reculations-2 D. Ross R. Mattson 3
C. Tinkler E. Case 4
W. Butler L. Rubinstein 5
D. Eisenhut
.____6.._.
_ Present for the NRC Office for Material Safetv-Standards ___
7 R. Bernero N. Fleishman
.+.
8
. Present for the Office of Inseection and Enforcement:
9 Y. Stello 10 11 12 13 14 15 16 17 18 19 20 l
21 l
n 23 l
l'4 25 i
l l
l
- ' DERSON REPCRTING COMPANY, :NC.
,t l
- 3... 1 v-,
=anse-dpe of a. =ne" g EM=:
~ -
- d*
is an u=offd d='
"e-C6.a62
~-
% 23
$ca:as :Tuclaar ?.agula:s:7 Ca.sion half. ce 2 --;-
[_ ~.
.. _, _.1:r$a-Commissian's officas-a= 1717 I Straec, 3r Wy, ~4=# =g.., -
~ 2:21
- g. _.._. -.. L.C.
De.2ee:128 7*4 cpen 02 pubT#* a*:mmfam w and cirstdiold.
I 2 Z
... Qis, &*?c 'sas =mc beaur ;urimred;, cc==ned_ _d'Eddisii".,_2 ant e
R._.
t= ag7 m g== maga,,
l l.....
- - --- -_.ya --*wer-d.pe is i==amdad, solaI7 for gana=..z.L ihfa2 cniEi l: 2
.pu= poses.
A.s prrric. d,.s7 10 CZI.9.103, i: is =.._.ce ?a== c: -d.er.____
e p.,._.__._.
__. f..s_=.=.a.1 cr i=fs==a.L :scord of 9d *t-n of he 4 ~.
dd~ sci.s~i T.-
- ~- -
~
- 1.... _...
_. J.zpre s =d ~~_. of cod-d __ i=. -6 d * =z=sc=d.g: da e:Cficissa=_1'.y
'. ~ ~.%
- - 2 2
Mac: fi=a.L da"** ***".d.2Es er ha T d a #*.
IIC pl_a_s.1:$ c7 4 Cat ='--
,-..., _ _.,. paper,.":37 De. filed. *sd "'*.he CC=Wis3123,i: &=7 p'iic f=4#N Ss -:ht- ~ '~" "'~
_. _ _ _. _. -. _. :ssu1= cf c= add =assed. :n an7 s a: aman or a.M;-i==-'"-*#C 2-
" -- J
. ~ _,
hS=313, 42CapC as *ba. C*"""d **I*R
&7 aU hC" 24.- - --
I 1
I l
l l
?0DROR0NM
__-_.,.,-.-_m--.-.-
i 3
l
- i. - -
1 112CIIEIIE1 2-CHAIRMAN HENDRIEs The Commission will come.to:
3 order.
4 We meet this morning f or a briefing on a possible 5 interia hydrogen control rule.
This is a proposition which - -
~
6 was out for comment last fall in a slightly different f ora.-
7 Note recently, and in particular since we agreed -to allow -
8 the Sequoyah plant to go on a full power with a: system of_.
9 ignitors in the containment as part of their-hydrogen i
10 control scheme, both Commissioner Gilinsky and I.have been 11 very anxious to see down a rule on hydrogen control.which 12 would apply until such time as the. Commission, in its 13 visdom, may vork through longer range proceedings in 14 connection with the degraded core rulemaking.
15 We have got it down here now.
I must say, I have l
16 had a hand i.a saying what I wanted to see in it.
So, in 17 part, what you see, I will have to accept the generalired 18 responsibility for, if not the detailed.
19 There are assorted complications to it.
The 20 connection between this proposed rule, and the conversion 21 which we have requested the staff to draft, the near-term 22 operating list requirements from NUREG 0737 in the form of a 23 proposed rule. 'Some of what we have got here in this 24 interim hydrogen rule also appears in that draf t, and I have 1
25 some suggestions for us on thi.: after a while.
l l
ALDERSoN REPORTING COMPANY,INC,
4 l-1-
There will also be a question which we will need 2 to consider as we talk about this hydrogen rule, and that 3 has to do with whether it ought to go around.for another 4 ' comment round.
I think ELD is inclined to think that that 5 is preferable.
I think that that is something that ve.could 6 haggle about and get the General Counsel's view, and see.
7 what we think, once we see how we like the pieces that are- -
8 ~ presented here, and whether some or all of them-are things 9 that we would like to think seriously about going.on forward 10 with.
t I
11 With that auch of an introduction.
We have Kevin 11 Cornell, and Denny Ross.
I see even that visitor, if not to
- 3 say, refugee, from the Environmental Protection Agency.
l 14 Welcome back, Roger.
15 Kevin?
16 3R. CORNELL 4 The only thing I have to add to your 17 comments about these proced' ural questions is whether or not 18 we may have to go out for comment again.
I know there are 19 some questions in the staff's mind of certain implementation 20 dates which we can get into.
I think those two areas, once 21 we get into the discussion, we will want to sort of lay out 22 some more what changes have to be made.
O 23 Right now, I will turn it over to Danny.
l 24 ER. ROSS:
Let's put the first slide up, please.
25 (Slide.)
i ALDERSoN REPORTING CCMPmY. INC,
l 5
l 1
3R. ROSS.
The order that we are going to go into-2 - this mornings I want to make a few comments.
I would then 3 introduce Hort Fleishman to discuss his role, which was-the,.
4-task leader on converting various documents-fron.Short Teras-5 -Lessons Learned in the Action Plan into a proposed cule, and-l 6 then evaluating the comments received in the-last f ew
[
7 months.
1 8
At a point during the briefing, Guy Cunningham.
U 9 from ELD zar want to elaborate briefly on the-question of to whether certain segments of the document in front of you.
i 11 need to go around again as a proposed rule.
12 Then, as far as the implement for operating 13 reactors, or for operating licenses, Roger Mattson from NHR 14 is going to discuss that.
15
.We have in the last f ew days,. in the final reading 16 of the document, identified a few, what we think are f
17 relatively minor, changes that we think are appropriate in l
18 the actual phraseology of the rule.
We may get to that 19 later on also.
I don't think these are very important.
20 If we go to slide two, identifying the topics of f
21 the rule, which is not truly a hydrogen rule.
As the title 22 of the staff paper, which is SECY81-245, indicates, it is 23 hydrogen and, and the "and" includes certain degraded core 24 considerations which have to do with the transport of 25 radioactive material, leakage monitoring, monitoring of ALDERSON AEPORTING CCMPANY. INC.
l 6
1 inadequate core cooling.
2 These 14 topics are rather diverse topics.
They 3~ pertain not only to hydrogen, but also to degraded core.
4 They are among the ones that we think ought to be qualified-5 by rule earlier than th e rest.
6 What I would like to do is to get Mort Fleishman 7 to pick the last few months since the Federal Register..
8 notice went out.
9 Nort.
10 ER. ELEISHRAN:
The rule primarily addresses the 11 specific items that vere identified in the TMI-2 lessons 12 -Learned Task Force Report, NUREG-0578, and we essentially 13 tried to put them into legal language.
There are two new 14 items on that rule, items No. 2 and 3, which were added 15 subsequent to the proposed rule going out.
These two new 16 items were not previously covered, and they essentially 17 include information that was developed as a result of 18 licensing reviews of new ice condensers in the Mark III 19 plants.
{
20 The next slide please.
Hold on to that one, we i
21 may be coming back to it.
22 (Slide.)
f 23 ER. FLEISHMAN:
As you know, the Commission 24 approved this rule as a proposed rule on September 4th, 25 1980, and it was published in the Federal Eegister about a ALOERSON REPORTING CCMP ANY :NC,
l 7
1 1 month later.
We received 35 comment letters, many of these
~ ^
2 actually coming af ter the closing da te.
In-fact,.the.last 3 letter that we used and considered in preparing-this final
- ~~-
4 rule was received on February 9, 1981.
There.were-5 approximately 160 separate comments that were included.in 8 these 35 comment letters.
~ 7 Subsequent to the publication of the proposed:.
8 ~ rule, NU3EG-0737 was published, which was-a-clarification of.
9 the ?!I Action Plan requirements.
About four regional l
l 10 meetings were held during the month of September, 1980, to 11 get additional industry input regarding the implementation 12 date, and to provide additional guidance to industry on the t
13 clarification of the THI Action Plan requirements.
l 14 This final rule incorporates both the comments and letters that we had plus the input from the regional 15 18 m ee ting s.
We tried to make it consistent with-the final 17 dates that were in NUREG-0737.
18 The next slide,Elease.
19 (Slide.)
20 MR. F1EISHMAN:
The major changes in the final l
l 21 rule from what we originally published in the Federal 22 Register are listed on that slide.
23 The first item is the most significant, I believe,
- 24 and that was to require hydrogen control systems for Mark 25 III and ice condensers plants that could control an hydrogen ALDER $oN REPCRTINf3 CCMPANY. INC.
l i
8 1 generated from the reaction of up to 75 percent-of metal 2 water reaction.
3 COHNISSIONER AHEARNE Joe, would you pref er~ to:
4 complete, and then go to questions?
r-5 CHAIRMAN HENDRIE:
I would just as soon we move-6 rapidly through the staff's story.
I may-vant to cut it - at-7 some point, I have some questions of my own.-
8 CONHISSIONER AHEARNE:
All right.
9 CHAIRMAN HENDRIE:
With dispatch.
10 NR. FLEISHEANs We also added a paragraph on 11 survivability of certain safety systems that would have to 12 0 unction to assure safe shutdown and containment. integrity.
13 following a hydrogen burn, and it was made applicable to 14 plants that do not have inerting.
So plants.where burning-
'15 might occur, they have to show that the safety systems can 16 function during and following a hydrogen burn.
17 We also clarified and limited the scope of the l
18 analysis that was required to basically now justify the l
19 hydrogen control system that was selected as part of the l
20 earlier rule change, and also to insure that safe shutdown l
21 and containment integrity can be maintained.
22 We also added an internal recombiner as being 23 acceptable in lieu of external recombiner capability, which 24 is what we had intended all along, except that apparently 25 there was a misunderstanding.
ALDER $oN REPORTING COMPANY,INC,
l 9
1
- de have modified the implementation dates to be 2 consistent with the dates in NUREG-0737.
I-believe it is 3 consistent with NUBEG-0737 that was published.
A possible 4 change, and Boger Hattson will be discussing that also, is.
5 whether or not there should be different dates for OLs or 6 operating reactors.
These are going to be discussed in a-7 few minutes.
The rule does not have those dates.
8 Next slide, please.
9 (Slide.)
to NR. FLEISHNAN There was a var
- ation in views in 11 the staff concerning, for example, the two new items that 11 were added.
OELD raised concerns about these, and indicated 13 tha t they felt that NBC would not be in compliance with the 14 Administrative Procedures Act regarding adequate notice 15 because these were not included in the proposed rule.
16 IE and NRR raised concerns about the schedules in 17 the rule.
Finally, the 31sk Assessment staff still has i
i 18 maintained that they feel inerting was not obviously risk 19 effective, and this was pointed out in earlier SECY papers l
l l
20 last year.
21 (Commissioner Bradford joined the meeting at 10420 22 a.m.)
23 MR. FLEISHNAN.
Next slide, please.
24 (Slide.)
25 MR. FLEISHMAN:
The major policy questions that we ALDERSCN REPCRTING CCMPANY, INC.
e 10 1 see associated with this rult are whether or-not to-inert 1 Mark I and II boiling water reactors; whether we should' hav.e..
3 hydrogen control systems for Mark IIIs and ice condenser-4 plants that can control up to 75 percent metal water
~
5 reaction; whether or not to incorporate the. specific items.
6 of the THI Action Plan into the rules that were identified 7 in the THI Action Plan; and, finally, the question.of when' 8 the rule should be implemented for plants which: have not yet t
9 received their operating licenses, and for plants which have-10 and are now operating.
Should the implementation dates be-11 the same, or should they be different?
This will be 12 discussed in more detail by Boger Hattson.
13 That is the end of my presentation.
14 HB. ROSS:
If you want to jump right into the.
15 implementation scheme, we can do that, but it might be 16 better if you want to talk about the technical aspects of 17 the rule.
It is your choice.
l 18 CHAIBMAN HENDRIE:
Let me talk about sort of a 19 structural aspect.
l 20 let's go'back to that slide which listed the 21 subjects.
22 HE. ROSS:
That is s,lide two, the technical 23 scope.
24 CHAIRMAN HENDRIE:
When this thing went out last 25 fall, in spite of being called an Interim Hydrogen Rule, it ALCERSoN REPORTING COMPANY,INC,
l 11 f
~
1 had a couple of items on hydrc' gen, namely, one and 4..
2 COMMISSIONER AHEARNE:
It was not called an- -
3 Interia Hydrogen Rule.
4 CHAIRHAN HENDBIEs What was it called ?
5 COHNISSIONER AHEARNE:
It was called Interia 6 Requirements Related to Hydrogen Control and.Certain 7 Degraded Core Considerations.
8 CHAIRMAN HENDRIEs It went out with one and-four, 9 some stuff connected with hydrogen, then, I-guess, five, and 10 then an array of items mostly from the Short-Term Lessons 11 Learned.
12 I have asked you to come. back in with the Sequoyah 13 solution for ice condensers, and the things that we looked 14 at for the CP rule for Mark IIIs, possibly post-containment 15 inerting with CO2.
16 As I look now at the way the rule is structured, I i
17 conclude that for my own purposes I see a high need to 18 provide an interia rule for hydrogen control specifically l
19 until further, longer-range considerations can supersede the 20 interim guidance.
21 I think we ought to cut the hydrogen rule after 22 item six, and make it an Interim Hydrogen Control Pule.
The J other items appear essentially identically, if not exactly 24 iden tically, in the rule the staff is drafting to convert 25 0737 into rule form.
I just simply propose to deal with i
l AL.DERSoN REPORTING CCMPANY. INC.
t
l 12 1 those 'hings along with the other 0737 items.. I think, in-2 fact we have that draft down before us.
3 What I would like to do is see what the sense-4-2Aong the table is on the Commissioners' side- - because:if 5 the Commission was inclined to agree with that cut-on the 6 rule, then we could talk about the hydrogen - parts-of it from 7 then on, and just focus on those.
l 8
Vic, how do you feel?
9 COHNISSIONER GILINSKYs It sounds okay to s pli t - -
10 them into two separate pieces.
As for what you do with 11 seven through 14, we could either follow your suggestion or 12 adopt them, and that would simply leave less for the other 13 cule that we were talking about.
14 At the-time this was put together, we had not 15 worked on developing the rule on the rest.
16 CHAIRMAN HENDRIE:
We had not contemplated a rule 17 on the rest of it.
I guess these were items which were 18 strong in people's mind, and there was some argument going I
19 on out in the field.
It seemed like a good idea to chuck 20 them into the rule and stop arguing about them.
21 Since we have the 0737 draft at hand now in rule 22 form, it seems to me useful to cut this and stick to 23 hydrogen.
24 John?
25 COMMISSIONER AHEARNE.
I guess, since we have ALDERSON REPORTING COMPANY,INC,
l I
13 1 already gone through the comment period on these, I have no-2 problem separating the two pieces, but I would :go-with - that-3 second seven through 14 now.
4 COMMISSIONER GILINSKY Are these absolutely - -- -
5 identical to the formulations in the new proposed rule that.
6 we are working up?
l-7 MB. MATTSON.
They were supposed to be.
We asked--
8 people to check them in detail, and it is-our. intent that
(
9 they be identical.
l 10 There is one thought that has not been interjected l
11 that bear; on this discussion that is going.on, if.I might.
l 11 The question of whether to put them out nov if the. work is 13 all done, they have had comments on them, and we might as L
14 vell go ahead and achieve that efficiency is.a good l
f 15 argument.
I 16 There is a counter-argument that says, in 0737 17 there are a lot of things to be done.
This subset of seven 18 through 14 is part of that, but there is about ten times 19 that many in 0737 altogether.
One can argue that it would 20 be good to take the opportunity of looking at all of those 21 0737 requirements together, since there is a lot being done 22 in the industry.
People are busy, and you cann at do it all 23 at once if you want to do it well.
24 By comparing one with the other in tee whole 0737 25 set, you might decide that the implementation dates, which ALDERSON REPORT 1NG COMPANY,INC,
~.
l 1u 1 you want on numbers seven through 14, are slightly - differen t-2 than you would decide that you did in isolation today.
The 3 implementation dates are something th at con tinue - to bo ther 4 us.
We have over and over learned that we are too 5 optimistic on how fast things can be done.
6 I think you heard in early April fros 3r. Eisenhut 7 that the 0737 dates might require multiple shutdowns in some-8 cases, or they night be too tight in some other cases.
F COMMISSIONER AHEARNE:
Of course, originally-0737,.
to as it was titled, anA Jtill is, I see, is requirements for
~
11 ope rating license applications.
12
- 53. MATTSONt Yes.
I presume that what we are 13 talking about here is making the 0737 rule applicable to j
14 both OLs and OBs.
15 COMMISSIONER AHEARNE:
I was just addressing what l
16 ve have here.
17 CHAIRMAN HENDRIE I think that is a subject that 18 ve ought to discuss.
Indeed, 0737 started out as the 19 near-term operating license list.
I know that the staff has 20 f ramed the 0737 conversion into a rule as a rule which would 21 apply, I guess, across-the-board, certainly to everything 22 with the construction permit.
23 MR. ROSS:
Yes.
24 CHAIRMAN HENDRIEs However, there is a question 25 with implementation dates.
We have already said to people, 7
l l
l t
ALOERSoN REPCRTING COMP ANY,6NC.
i 15 l
~
~ ~
1 coming up for operating licenses, 0737 is part. of the.
2 threshold for an operating license.
But.you-have to watch 3 out for the operating reactor implementation dates for an :
4 assortment of reasons, not the least of which is-that it is-5 not just a question that we are beginning to heap up more-.
6 than can be reasonably done by plants out-there with th e-7 available resources, engineering manpower, and so on.
-I-1 8 think it is rather more profound and important to. us. than-9 that.
10 I think that we are beginning to heap up enough.
11 stuff, which we are requiring a t operating plants, so that 12 with groups of contractors rushing.around, trying to execute 13 this change and that, and the plants and utilities engineers 14 stretched thin trying to keep track of all of these. people 15 running around, and answering NRC requests for further
' 16 analysis, I as very concerned that we are beginning to l
17 leave, at least some of the plants in a situation where the 18 activity is substantially degrading safety.
19 I think that it is high time, with what we will 20 have to do for seven through 14, treated alone or with the 21 0737 list, we are going to have to stand back and look very I
22 carefully that the pace of these things as they are 23 implemented in the field is not getting beyond the place 24 where the operating organization can accommodate the changes 25 that are occurring, work them in so the operators understand ALDERSoN REPORTING COMPANY. INC.
16 1 them as necessary.
That we don' create that-sort of 2 situation.
3 COEEISSIONER AHEARNE:
I would think that that-4 arguacnt would hold even stronger for items two and three.
5 CHAIRMAN HENDRIE:
I think it, indeed, does.
Do 6 you regard high point vents as equally important as having 7 some way to deal with more hydrogen than 5 percent in these 8 intermediate size containments.
If you don't,-then.you say, 9 the whole list ought to be treated as part of 0737.
I think to at least regulatory reasons, if not for technical safety.
11 reasons, hydrogen control urgently needs to. be addressed in 12 rule form.
13 I will say that the implementation dates that are 14 proposed of January 1st, 1982, I,just don't think so, 15 fellows, not on the ors.
l 16 MR. CASE:
We have some comments on changes in the 17 implementation dates.
i 18 CHAIREAN HENDRII:
You would take the whole 19 batch?
l 20 Do you think you would be willing to s pli t,
21 Peter?
22 (General laughter.)
i 23 CHAIRMAN HENDRIE:
Let 's talk abo ut the hydrogen 24 part of it.
25 COMMISSIONER GILINSKY:
Since that is the high ALDERSCN REPORTING COMPANY. INC, l
I l
t t
17
- - :~
1 point, then let's go on with hydrogen control.
2 CONNISSIONER AREARNE:
I agree.
- 3 CH AIRH AN HENDRIEa Yes, but there are also pieces 4 of hardware and other aspects.
5 ER. NATTSON:
The way it is phrased, it is phrased ~
6 to include other non-condensables, like the-nitrogen fron-7 the accumulator.
8 CHAIRMAN HENDRIE:
You could even toot some steam 9 in'there.
10' Let's talk about the hydrogen side, particularly 11 with regard to you have talked about, dates,.0Ls, ors, and 12 what else?
13 COMMISSICNER GILINSKY:
Was he going to talk about 14 the techtical side of the proposals?
15 CHAIRMAN HENDRIE:
I prefer to talk about the is technical side of the hydrogen proposals for the moment.
17 COMMISSIONER GILINSKY:
Right.
18 CHAIRMAN HENDRIE4 Your choice, Roger, any order.
19 HR. MATTSON:
Let me just introduce it and see 20 whe re it goes.
21 I gather we are talking about items one through 22 six.
Certainly, item one, -ites five, and item six are 23 com ple tely consistent with decisions that you have reached, 24 Short-Ters Lessons Learned, Action Plan, the proposed 25 version of this rule, and not much has changed.
ALDERSoN REPORTING COMPANY,INC,
18 1
The schedules for five and six, we would want an-2 opportunity to talk about before they go out -in -exactly ; the. _
3. form they are in now.
I think the schedule with number one, 4 :ve are probably still sticking with what is.in this rule, 5 although, Darrel, you might want to correct.me.
~
8 HR. EISENHUT Just one minor change to that.
M:
7 Historically, when we went with' plants that were.._
8 inerted, Ma rk Is, there has always been a: period of time _
9 right when the plant starts up, where they go through a 10 start-up phase, where they are going up and-down.
~
I 11 Historically, that period of time has been a number of 12 m on th s'.
13 We have not licensed any Mark Is for a while, but 14 if you go back historically, we always came up with a period 15 of time after issuance of the OL before they had to be 16 inerted.
So we will be following the 1-1-82 on the Mark 17 Is.
We would stand by that date, and say that the two 18 uninerted Mark Is should be inerted by January 1,
1982.
V l
19 ermont Yankee and Hatch.
20 For Mark IIs, we would propose probably changing 21 to something like after the OL issuance.
22 COMMISSIONER AHEARNE:
Which will be the first 23 Mark II?
24 MR. EISENHUT:
La Salle, which is scheduled right 25 now to come before the Commission, I think, next month.
I l
ALDERSoN REPORTING CCMPANY. INC,
- \\
l 19 1
l
~
~
1
, COMMISSIONER GILINSKY:
The point of giving'then j
2 some time is what, to allow more flexibility-at the 3 beginning?
4-MR. EISENHUTs Right, and then you are going 5 through the start-up phase, up until you have generally-gone-6 through a 100-hour demonstration run at full power.
You-l I
7 vant them to have free access to be able to get in and out l-l 8 of the plant.
Particularly if anything is going wrong, you - '
9 certainly don't want to have to go in with special 10 equipment.
11 CONNISSIONER AHEhBNE:
Is this the time when we l
l 12 can ask question?
l 13 CH AIBHAN HENDRIE:
Yes.
i l
14 COMMISSIONER GILINSKY:
Don't restrain yourself.
15 COMMISSIONER AHEARNEs Darrel, Roger, or someone, 18 I gather, particularly from the introductory c.sments with 17 respect to research, that there is no new information 18 regarding the pros and cons of inerting that have not 19 discussed over the previous many meetings that we held?
20
- 53. MATTSON:
I think Denny might want to bring up l
21 one.
22 MR. ROSS:
One of the comments received, it is 23 new, transmitted a report given at the IAEA Conference last l
1 l
24 October, which of course would be subsequent to the 25 Commission's approval.
It is a study by, I believe, some ALDERSON REPORTING CCMPANY,INC.
20 1 people from MIT.
I think the best thing to-do-is just to 2 get Bob Bernero to summarize what it says.
3 MR. BERNER0s Basically, there is that one 4 comment, and there was also a letter not.very long ago 5 citing the incident Cape Canaveral, the fa talities in the 6 inert gas.
7 That paper that was presented at the conference 8 last fall basically goes into establish the.
9 counterproductive character of inerting.
There is a 10 fundamental assumption in it.
11 If you recall, when we discussed last fall with 12 the Commission what is the problem of doing a rigorous risk 13 assessment of inerting and the competing risks, you are 14 dealing with scenarios that the risk assessments have not 15 dealt with before, the truncated core damage.
16 The basic premise in that paper came as a comment 17 was, there is a fixed linear relationship between 18 probability and the generation of hydrogen.
It greatly 19 simplifies the thing, but there is no real basis to 20 establish the physical fact of that.
So I don't really see 21 that paper as persuasive one way or the other.
22 CHAIRMAN HENDRIE:
'4 hat is the assumption, again?
23 3R. BERNERO:
They basically said that the degree 24 of hydrogen generation is proportional to probability 25 directly, and consequently the higher the probability, the ALDERSoN REPORTING COMPANY. lHC.
_ _ 400 VIRGINIA AVE., S.W WASHINGTCN. D.C. 20024 (202! 554 2345
21 1 lower the quantity of hydrogen you are dealing wi th.
It 2 just basically makes the problem less of a threat.
The 3 characteristic becomes less of a threat.
4 The whole argument, and I as arguing someone-5 else's point here --
6 COMNISSIONEE GIIINSKY I an sorry, I missed -
7 that.
Whose paper is this?
8
- 53. BERNEEO:
There were some students at XIT, and 9 I have a copT here, Carolyn Helsing and Jose Leperbaush at to 5IT.
They presented it at the Stockholm Conference in 11 October.
12 NE. ROSSs I believe the.verk was sponset3d by the 13 Iankee-Europe.
14 53, BERNERO:
Yes, it was.
The owners developed 15 it.
16
- 23. 30SS:
Among o the r things, the y state that if 17 you can go in and icok at the plant, the probability per l
18 hour2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> or per year of a LOCA is decreased.
That is kind of a 19 simple 20
- 33. BERNEEOs Yes.
21
- 13. MATISON:
To the,;oint of your question, is 22 there anything new, no.
It is the sane argn=ent couched in 23 probability space, and Bob is saying that it was not well 24 enough couched to let you decide one way or the other.
25
- 33. BEENE20s It really doesn't give, at least in l
ALOEASCN AE*CRTWG COW 8AM :NC.
22 1 our view, that much of a new ' light on it, because you are 2 still confronted with a paucity of hard inf ormation-on - what 3 is the real distribution in probability space of core damage
~
4 as against core damage mixed with corenelt all in a-lump.-
5 Further, there was the argument that the Cape-6 Canaveral -- I can 't remember who wrote the le tter, but it-7 was to the Chairman or to the Commission.-
We have known all 8 along, and everyone who has worked in heavy industry knows 9 that inert gas can kill, it has done so periodically.
It is 10 really no new information.
l 11 COMMISSIONER AHEARNE:
So the arguments are really 12 still the same?
13 MR. BERNERO:
Yes.
It is essentially the same 14 information base before you.
15 COMMISSIONER AHEARNE The basic calculations have 16 not been changed either, so if we follow the analysis on a I
17 cost benefit, you would not necessarily come out with 18 inerting as the thing to do; is that correct?
19 MR. BERNER0s I would say, yes.
The argument 20 stands pretty much as it stood before you last fall, and I 21 would be quick to point out, the presence of the statement 22 of the Office of Research, of the Probabilistic Analysis 23 staff, still stands on the other side room.
It is not that 24 we have had an agonizing reappraisal, and come down hard 25 again.
It stands where it stood last fall.
ALDERSoN REPORTING COMPANY,iNC.
23 1
COMMISSIONER.AHEARNE:
Nothing has changed.
2 The costs of inerting are, then, also, I ga th e r --
3 You have sentioned a cost in here, which I guess is like $2 4 million for a plant that is not inerted, and_somewhere 5 around $300 million over the lifetime of Mark Is and IIs.
6 MB. ROSS:
Hight.
7 COMMISSIONER AHEARNEa I guess I also was 8 surprised to see Suffolk County coming in-and-saying that 9 you should not inert.
to MR. ROSS:
Ihey are vorried about the costs to the 11 people who use the utility, the extra costs of the inerting 12 being distributed.
13 CHAIRMAN HENDRIE:
Who is that, Suffolk?
(
14 MR. ROSS:
Suffolk County.
15 CHAIRMAN HENDRIE Write them back, and tell then 16 if they are worried about the costs, to gat out of the case 17 and let the plant operate.
18 (laughter.)
19 MR. MATISCN:
We are ready to move on to items 20 two,three and four.
That is all on item one.
l 21 Ihe hydrogen control for Mark III and ice 22 condensers is an attempt on our part to put in regulation 23 language what we think has transpired in the course of 24 licensing reviews of Sequoyah, and looking down the road at 25 the reviews of Grand Gulf and other plants.
A1.CERSoN REPORTING CCMDANY. INC,
l 24 1
There is a statement in the statement of
-2 considerations that bears pointing out to you,-actually two i
3 of them.
l 4
One, a passing statement by the staff in the-5 language that we propose for your acceptance.that inerting 6 is preferred over burning, if inerting ways _for particular l
I l
7 containment designs can be found.
There are some designs l
8 that you have looked at, and we have looked 1at, where 9 inerting doesn 't look possible.
10 COEHISSIONER AHEARNEs Is that pre-or post-11 MR. NATTSONa The statement of consideration l
12 doe sn 't really say, inerting.
I t sa ys, systems that 13 mitigate hydrogen without burning are preferred over systems 14 that deal with hydrogen burning.
15 COMMISSIONER AHEARNE:
That would include 16 post-accidents?
17 5R. NATTSON:
Post-and pre, yes.
18 Another point is bringing to your attention, in
(
19 case you haven't seen it in other places, the fact tha t 20 there still are some questions about distributed ignition 21 systems.
There are questions that have arisen on the 22 Maguire Docket, questiocs that continue to be addressed in 23 on-going research and analyses.
24 I think you will remember that the Sequoyah 25 solution had a one-year proviso on it.
At the end of a ALCERSoN REPCRTING COMPANY,INC.
25 1 year, we would be in a position to answer the question.of 2 whether the hydrogen sitigation system was the-right system 3 for the long-term..So we point out again in the statement-4 of consideration, just in passing, what some-of the 5 continuing interests are.
6 The staff continues to believe that the bottoa 7 line is distributed ignition improves safety.- It does-not 8 d etra ct from safety, but there are questions to be answered 9 on exactly how to fine-tune the distributed ignition systen 10 to get the most out of it that you can.
11 COHNISSIONER AHEARNE:
Have you analyzed it for 12 Hark III?
13 HR. MATTSONs We haven't.
I believe that Grand 14 Gulf has filed a design f or the Mark III system.
l l
15 HR. EISENHUTs There is actually a submittal in on l
16 Grand Gulf.
The two upcoming Mark IIIs have very reewntly 17 told us that they are going to be going with the distributed 18 ignition systems as opposed to inerting, be it pre-or 19 post.
There were technical considerations why they have 20 opted not to go post-accident inerting.
21 ER. MATTSON:
Primarily because they are concrete 22 containments.
l 23 ER. EISENHUT They just don 't like to put that 24 extra load on the containment post-accident.
1 25 The only other commer.t on item two is the two As.0ERSCN REPCRTING CCMPANY. INC.
i 26 1~ operating plants, Cooke I and II, ara, of course, ice 2 condenser plants.
We sent them a 50-50 uF letter a couple 3 of months ago, and we have been working with them and 4 telling them that they do have to put in same. form of 5 hydrogen control.
6 The question is, of course, can they have it in by 7 January 31, which is wha t this rule would require.
We think 8 that it is going to be close, and it is going to be tied to 9 whether, in fact, they can get the system in for the Cooke I 10 shutdown, which is scheduled in May of this year, and the It second system comes down in August of this year.
12 So we would opt to leave.the rule as it is now, 13 but recognize that we may have to grant them a exemption to l
14 the rule if they cannot have the system installed.
15 COMMISSIONER AHEARNE:
Have you gone through the 16 analysis of the Grand Gulf submission?
17 HR. EISENHUT No.
It is brand new.
It just, in 18 fact, came in.
In fact, this week is when the second Mark 19 III also just inforscJ us that they are going to be going 20 distributed ignition.
1 21 COMMISSIONER AHEARNEs
'ih y did you choose 75 22 percent?
23 MR. MATTSON:
It says in the statement of 24 consideration that there were two reasons:
Trying to reach 25 some balance between what is in mind for the long-term.
I ALCERSCN AEPoRT1NG CCMPANY. INC,
27 1 Uvith the CP rule, for example, of 100 percent in coronelt.
2 One hundred percent metal water reaction and coronelt are 3 very difficult to distinguish.
4 C0!!ISSIONER AHEARNEs The CP rule was focused 5 also on a specific set of plants.
6 ER. MATISON:
The feeling th a t wh at we were 7 talking about here was the window of degraded core
~
6 accidents, and not the complete corenelt spectrum of 9 accidents, and a judgment by the staff that at about 75 10 percent, r4 person could still make a technical argument that 11 it was reasonable to expect that the cooling was 12 ree stablished, the core would be raccoled, and stopped short 13 of a corenelt down, but beyond 75 percent those arguments 14 are sore difficult to make.
15 T0!MISSIONER AHEARNE:
The reason that you did not i
16 go a lower percentage?
l 17
- 53. NATTSON:
Iou can't go such lower because THI, 18 the range of estimates is 30 to 50 percent, I as told today, 19 and 75 perrent looked like about as far as you could go and 20 still be within the realm of degraded core accidents.
21 COEMISSIONER AHEARNE:
Yes.
22 ER. MATTSON:
There is a lot of judgment in the 23 number.
It is not, here is a definitive analysis that 24 clearly shows 75 percent.
It is what the rule says about 25 75.
1 ALOERSoN RE*oRTING CCMP ANY. :NC.
28 1
COMMISSIONER AHEARNE:
Do you have a sense that 2 the Mark IIIs can meet that?
3 BR. MATTSON:
I would have to defer to my staff to 4 say whether they have done that much detailed thinking about 5 the Mark IIIs at 75.
6 Did you hear the question?
7 HR. BUTLEHa Yes.
8 The studies done a year indicated that they should 9 be able to accommodate 75 percent.
The Grand Gulf Docket to had this filing recently by MPCL, and we have not had a 11 chance to study'it, but my assumption is that they can 12 accommodate the 75 percent.
a ER. MATTSON:
I as ready to move to number three.
14 The 75 percent is a good reason to move to number three.
15 This is a,new requirement.
This doesn't come 16 directly from the Sequoyah or the Mark III considerations.
17 The staff looks at the number that has been agreed upon in 18 those contexts, the 75 percent, and says, well, if the 19 design basis for these reactors in those containuents is 75 20 percent, what about the large dry PWBs?
There is no reason 21 to say that they should not expect 75 percent mesal water 22 reaction if the expectation is to expect 75 percent in the 23 ice condenser containment.
24 So this requires all plants that depend upon 25 burning ALDERSoN PEPCRTING COMPANY,INC,
29 1
COMMISSIONER AHEARNE:
You mean to be protected 2 against, rather than expect?
3 ER. NATTSON:
Yes.
-~
4 This requires all plants that depend upon burning, 5 in order to cope with hydrogen, to show that burning does 6 not disable the critical safety equipment needed to cope 7 with core cooling.
8 In the case of the ice condensers and the Hark-9 III, it doesn't really add anything.
Where there is burning to that goes on in those plant:s because of the -distributed 11 ignition system, the licensee must do analyses of the 12 temperatures and the equipment to show that it will survive 13 that burning.
14 Item three goes on to say, for la rge, dry PWRs, 15 that where burning would occur, if the 75 percent metal 16 water reaction occurred, they must also demonstrate that the 17 safety equipment can survive the temperature effects of that 18 burning.
19 C0!!ISSIONER AHEARNE:
I didn't get, in reading 20 that in the rule, that it was clear against what criteria 21 this survivability would be measured.
22 ER. ROSS:
There is a key word between 23 qualification and survivability, and it meant stevive, which 24 is a less severe design requirement than qualify.
It did 25 not mean qualification.
ALCERSoN REPCRTING COMP ANY. INC.
30 1
COMMISSIONER AHEARNE:
But there still would have 2 to be something against which, either a licensee, or a 3 board, or IEE, or 3RR would measure, and I couldn't find 4 Lt.
5 MR. MATTSON:
I think part of the difficulty is 6 that this is a fairly new area.
What generally happens in 7 the burn is a rapid rise, and then decrease in 1ccal 8 temperature during which the component may or may not heat.
9 up, aar or may not burn depending upon its properties and 10 its size.
11 COMMISSIONER AHEARNE:
Let me focus my question.
12 What the rule says is that if the BWR and the PWR doesn 't 13 rely upon an inerted atmosphere, shall be provided with
(
14 systems, etc., that are capable of performing their 15 functions during and af ter being exposed to the to enviranaental conditions created by the burning or local 17 denotation of hydrogen.
18 I was wondering if there were any set criteria for l
l 19 that environment that the licensee, or NER --
20 MR. MATTSON:
No, I don't believe there are.
The 21 first cut would ce to compare the temperatures thr t would 22 occur in the critical equipment with the temperatures to 23 which that equipment has been previously qualified.
24 COMMISSIONER GIIINSKY I felt tha t we were in the 25 process of developing such criteria; are ve not?
ALDERSCN RE#oRTING COMPANY. INC,
31 1
- 53. ROSS:
We did some work on an ad hoc basis for 2 the Sequoyah plant, and did a bit more om Eaquire,.which -
3 started out with the licensee identifying their systems,_and 4 then --
5 COMMISSIONER GILINSKYa If we don ' t have them - nov, 6 I want to be sure that we a re at least working on them.
7 COHNISSIONER AHEARNE4 The way we have the rule, l
8 it says that this equipment shall be capable of operating in u
9 a certain environment.
The environment is burning hydrogen 2
to or local detonation.
I would expect that anyone, trying to j
11 either design the equipment, to prove its meets the rule, or 11 examine whether it meets the rule,.needs some kind of l
13~ environment that is meant to define burning hydrogen or 14 local detonation.
15 ER. MATTSON:
That is true.
As yet there have not 16 even been such analyses, item number four, hydrogen burning 17 in these containments and these conditions.
l 18 COMNISSIONER AHEARNE:
Except tha t by Janua ry 31st' i
19 of 1982 --
20 MR. MATTSON:
We would like to change that date, l
21 however.
22 MR. EISENHUT:
I think, in fact, what you said is 23 absolutely right.
24 The industry, I guess I should say on items two 25 and three, both, we met again yesterday with the steering l
ALDERSoN REPCRTING COMPANY,iNC,
32 1 committee of the AIS to ask them, you know,-can these dates 2 really be met, because it particularly came out of the E-2 3 program, because we have been at environmental l
4 qualifications since 1977, and there have been.very, very 5 great problems making the June 30, 1982, date.
6 They point out, "You have not done the analyses.
l 7 You have not done some of the experimental work.
You have 8 not defined the criteria of what the equipment is going to S have to be, and you really need that experimental program to 10 define tha criteria that it is going to have to meet.
Then 11 likely you are going to have to go develop some of the 12 equipment."
They argued with the staff and pointed out that 13 we are just completely in Dreamland saying, 1-1-82.
14 As Roger said, we have been rethinking that date.
15 For ors, we think that date is going to have to be obviously
'S delayed somewhat.
Also, until we decide (a) what it means, 17 (b) it would make sense to delay until af ter the June 30, 18 1982, program where they argue that every single engineer 19 that can probably work on this subject is already working on 20 it.
21 At the same time, it would seem we have to develop 22 a schedule that is as soon as practical to really arrive a t 23 that objective.
It clearly is beyond June 30, 1982, and it 24 may very well be -- If I had to pick a date today, I would 25 say, January 31, 1983, which is one year after the date in ALDERSoN REPORTING COMPANY,INC,
... -.. ~. -.
33 1 here.
But I would speculate that it is not going to be met, 2 just like the June 30, 1982.
3
~
We really don't have a real good handle on trying.
4 to pin down what the date would be.
5 COMMISSIONER BR ADFORD s Darrel, Why would you use-6 Jan ua ry 1983?
7 HR. EISENHUT:
You have t,o shoot at a target.
8 That is the same question that I think you certainly were-9 instrumental in when we came up with a schedule of a target 10 to shoot at.
At this point, if'you don't really establish a 11 firm schedule, it is doebtful if we will ever get there.
12 So you have to, at some point, lay out a schedule 13 and say, "This is what we are going to try to n ee t, " and 14 suster all the forces in the industry to try to really make l
15 an effort to meet it.
COHHISSIONER kHEARNE:
Do we have an internal 16 17 schedule of when we will come up with the criteria?
18 HR. EISENHUT:
I don't know.
I have not heard of 19 one, if there is one.
20 NR. ROSS:
I would like to point out that 'on the 21 technical aspect of determining what the appropriate threat 22 is, the hydrogen burn threat, is that we believe that we did 23 this in our review of Sequoyah, hnd to a better degree on 24 Maguire.
With the Haguire records in front of you, you can l
25 just see for yourself --
i ALDERSoN REPoRitNG COMPANY. INC.
34 1
COMMISSIONER AHEARNE As a matter of fact, I have 2 read a lot of those days of hearing.
3 MR. ROSSa I think the staff knows how to specify 4 the initial and boundary conditions for the hydrogen 5 threat.
Going from specification to execution is, indeed, 6 the thorny problem that Darrel is talking about.
I tLink we 7 know how to start, anyway.
8 MR. NATTSON:
It is our judgment that we can 9 afford to take time to develop some criteria, to do some 10 analysis, and to solve this problem.
We have been through 11 it to a limited extent with the ice condensers.
We have 12 been through it to a great extent with T3I II.
The accident 13 was better experiment than we will probably ever conduct on 14 hydrogen burning in a large dry containment, and its effect 15 on equipment.
1 16 So it is not the same kind of urgent problem 17 dealing with the survivability or the integrity of the saa.'.1 18 containments in our judgment.
19 COMMISSIONER AHEARNE:
The la st question on that, 20 if I can.
21 Pe; haps I missed the linkage in the rule.
Is 22 there somewhere that it does make that linkage that you Z3 mention, Roger, that this analysis is to be based on the 24 assumption of 75 percent?
25 3R. MATTSON:
I believe it does.
ALDERSCN REPCRTING CCMPANY, INC,
i e
l 35 1
ER. FlEISHMAN:
Ites four, which talks about 2 analysis, says that the analysis that the Commission has 3 required to mitigate the consequences of large amounts.of 4 hydrogen generated within eight hours after the start of an 5 accident, and then in parentheses, hydrogen resulting f rom 6 the reaction of up and including 75 percent of the fuel 7 cladding with water.
8 COMMISSIONER AHEARNE:
That is in f our.
I was 9 speaking about the ites three, which talks about that they to aust be capable to perform their functions in this 11 environment.
Is it clear that that environment is that due 12 to the burning of 75 percent of the hydrogen.
13 HR. 5ATTSON:
I think that coupling occurs in the 14 next page of the rule, actually, the page 23-A of Enclosure 15 C.
16 5R. ROSS:
At the bottom of page 23, and it 17 continues on.
The purpose of the analysis is to demonst~: ate 18 that the systems can, indeed, insure safe shutdown and 19 containment integrity.
20 MR. MATTSON:
The intent is to couple them.
Maybe.
21 the words are poorly chosen, and it doesn't do it.
22 COMMISSIONER AHEARNE4 The analysis has to be done 23 six months after the date of the rule for operating 24 reactors.
25 MR. ROSS:
Yes.
ALDERSON REPORTING COMPANY. INC.
m m
~
l 36 1
MR. EISENHUTs Let me comment on that one, too.
I 2 guess one other comment with respect to Commissioner 3 Bradford's question.
4 The industry made one strong plea, and that was on 5 these items that have not been out, for example, equipment 6 survivability, to put them out for comment.
To put 7 something out for comment, you have to propose a date.
You-8 are-required to propose a date.
9 That also had the same observation --
10 CONNISSIONER AHEARNE4 I really am sorry that 11 industry made those comments, because it almost sounds like 12 they have made them to me, which they have.
Nevertheless, 13 the rule that we have in front of us is a proposed final 14 rule, Darrel.
15 MR. EISENHUT:
I understand that.
16 COMMISSIONER AHEARNE:
It is not a rule proposed 17 for comment.
18 X3. EISENHUT:
Our recommendation was in the 19 beginning that some of the dates, we think, are due to be 20 rethought through.
21 Similarly, on the analysis item, the large dry 22 containments, we think the date here can be delayed 23 significantly to get that analysis in, because the large dry 24 containment has been shown, and we really believed can, in 25 fact, survive from a struerural standpoint in most cases.
ALDERSON REPcRTING COMPANY,INC,
~.
37 1 This is the analysis of the response of the~ containment, 2
etc., we believe it can be dela yed up to two years af ter - the 3 effective date of the rule.
4 CONBISSIONER AHEARNEs It almost sound like what 5 rou are saying is, the original rule that-vent out for 6 comment asked for an analysis of those.
7 MR. EISENHUTt Yes.
8 MR. HATTSON:
There was a much different analysis-9 in the proposed rule.
I did not get to analyses yet, and I 10' probably ought to explain that.
11 In the Action Plan, in 2-B-8, those of you who 12 still remember those numbers, we talked about the degraded 13 core rulemaking.
14 CONMISSIONER AHEARNE:
It was clever of fou, Joe, 15 to make sure he came back.
16 (Laughter.)
17 CHAIRHAN HENDRIE.
I did not think I would have to 18 kill EPA to do it, but you do what you have to do..
I 19 (Laughter.)
20 MR. NATTSON:
The ACES asked if we wouldn't try, 21 in the course of the interim rule, to require the industry 22 to do some analyses, so that the government did not bear the 23 burden of doing all the analyses.
The creative people in 24 the industry could be put to work on this problem.
In the l
25 proposed rule, some analyses were talked about in the same e
ALDERSoN REPORTING COMPANY,INC,
1 l
l 38 1 kind of language that was in the Action Plan.
2 Things changed after the proposed rule.
The l
l 3 Commission decided on Sequoyah to require some kind of 4 interia hydrogen sitigation system, and analyses were done 5 in that context.
It was broadened to include the Mark IIIs, i
6 and more analyses are going on 'in that context.
That led 7 the staff to conclude that if 75 percent was becoming the 8 number of interest then that is something that the large 9 dries ought to do analysis for.
10 Many people commented on the proposed rule that 11 the analysis needed to be better specified.
So the original 11 broad ranging request for, submit analysis and tell us what 13 rou can do in the interim about degraded cores, has now been 14 narrove quite a lot in this proposed rule.
We think that 15 that is the right thing to do.
16 We have come a step beyond what the Action Plan 17 contemplated, and what the AC35 contemplated about a year 18 ago, when the concept of those interim analyses was first 19 born.
So it is a much more specific analysis, geared 20 towards demonstration that the mitigation system works for 21 the ice condensers and the Eark IIIs, and analysis geared 22 towards the equipment survivability f or the large dries.
In 23 the case of the Mark I and IIs, no analysis at all.
24 While there is a pause, one of the things I forgot 25 to point out, as we are going along, somehow we left out the ALDERSON REPCRTING COMPANY,INC.
l 39 1 stainless steel cores in the proposed rule.
There was some 2 language on zircalor cores.
Of course, stainless steel does 3 react with water at a sonevhat higher temperature than 4 zircalor, does produce hydrogen.
5 COMMISSIONER AHEARNE:
There are not very many of 6 thes, are there?
7 5R. NATTSON:
Pardon me?
i 8
CONHISSIONER AREARNE:
There are not very many of.
9 them, are there?
10 ER. MATISON:
One.
11 3R. CASE:
There are more than one.
12 3R. MATTSON:
Rut the language has been 13 generalired to sweep into the rule the stainless steel 14 cores.
15 COMMISSIONER AHEARNE:
I guess the only comment I 16 would make to something you just mentioned, in addition to 17 forusing the analysis, you have also gone to requiring the 18 equipment.
19 MR. MATISON:
Yes.
That is the equipment 20 survivability point.
That is new.
It is not in the 21 proposed rule.
It was not highli;hted in any previous 22 discussions about THI fixes.
t 23 COMMISSIONER BRADFORD:
Denny, can you cone back 24 to the point you made earlier about the difference between 25 survivability and the qualification?
I guess I didn't quite ALCEASON REPCRUNG COMP ANY. INC.
u0
~
1 understand what you meant by that.
Once the-criteria have 2 been defined, what is the difference between-surviving them 3 and being qualified to withstand them?
4 MR. ROSS:
I think you could survive with some S loss of function, but I think you would qualify with no loss 6 of function.
It is a matter of extremity of the peril.
If T rou think you are a low probability sequence, then you might 8 tolerate -- let's say that it is a pressurizer level-a plus or minus 10 percent of span error.
But 9 instrument to if you were qualif ying it, you might have much tighter 17 specs.
12 COMMISSIONEH AHEARNE:
Isn't the purpose of the 13 qualification to assure that it can survive when needed?
14 MR. 305S:
With specified tolerance.
15 When we were looking at ~one of the ice condensers, 16 in fact, the approach chosen by the owner was to show that 17 the temperature from the hyd'rogen burn was within the 18 qualification envelope.
I think, clearly, if you survive l
19 and maintain the function, but suffered damage beyond that 20 ordinarily associated with qualifica tion, then I think that 21 would be acceptable by this rule.
22 COMMISSIONER BBADFORD4 Doesn't that get pretty 23 uncertain, once you start talking about a particular piece 24 of equipment being tested and almost breaking down, but not 25 quite.
How confident can you really be that another piece l
I l
ALOERSON REPORTING CCMP ANY, INC,
41 1 of equipment actually in the plant in almost the same 2 conditions wouldn't go over the line?
3 3R. NATTSON:
It is not a question of almost 4 breaking down.
Any piece of equipment, when-you strain it,
5 may r.o t be within calibration, or tend to up or down.
So in 6 the analysis, you ask yourself, if the thing generally 7 indicates a low because of stress at high temperature, does l
8 that make the analysis more or less conservative.
That kind l
(
9 of thing is done with norma'. environmental qualifications.
I 10 COMNISSIONER BR ADFORDa That is what I I
11 understood.
But what I thought Denny was saying was --
12 MR. ROSSa If it was a piece of cable that could i
l 13 burn, in that case I think the temperatures would be the l
14 same.
You would want enough margin below terminal damage, 15 and the two would be the same in that case.
But if it had to to do with just, say, a piece of electronics whose error 17 just got larger between qualify and survive, then you might l
18 be more tolerant.
19 COMMISSIONER BRADFORD:
That is what I was after.
l 20 It sounded as though survivability was sort of borrowing 21 from the margin that you normally have in qualification.
22 NR. ROSSa In some instances, I think the answer 23 is, yes, but if it is a cable carrying some power to a vital 24 valve that had a certain temperature beyond which the 25 insulation would start burning.
Then I don't think in that 1
i
\\
l ALDERScN REPcRTING COMPANY. INC,
i p
t 42 1 instance you wou.',d have a looser spec for survive than for 2 qualify, because that is a discrete state that either works 3 or doesn't, and you don't want to get close to the "not 4 work" state.
5 At Sandia, the Office of Research is sponsoring a 6 research program to better d'efine failure of some of these 7 items.
I don't have any details on it because it is still 8 in planning, but the research program should be. finished in 9 about 18 months on the effects of hydrogen fires on items 10 inside containment.
11 CHAIRMAN HENDHIEt How long are those burnings in 12 the research program?
Are those experiments?
13 ER. ROSS.
I am speaking of experiments, and I l
14 don't know whether Don Hoats has any more details or not.
Hoa7sost 15 ER. MCAIS4 Right now, we have got a cooperative 16 program going with the licensing sid e.
They are funding the 17 analytical work, and we are funding the experimental work.
18 The experimental work is going to involve burns to 19 characterize primarily the temperature environment, mainly
~
20 the radiation heat transfer to components that seems to be 21 the most important thing.
22 Once we have that characterired, there is a 23 facility at Sandia that uses very rapid heat up heat lamps.
1 24 As soon as we have the environment characterired, we can use 25 this facility and expose a number of components to radiant ALDERSoN REPORTING CCMPANY,INC,
43 1 heat transfer conditions that will simulate the burn 2 environment.
That is what we are planning to do.
3 That is just in the planning phase, and one of the 4'
problems we are facing is that we have the funds for the 5 experimental work and the analytical work, but we haven't 6 found the funds for the equipment that we are going to be 7 putting the environment in.
8 MR. MATTSOMs The discussion might suqqest that-9 putting three out for public comment isn't a bad idea.
j to CONHISSIONER AREARNE:
They might even suggest 17 something else.
l l
12 I have other questions on the rule itself at some i
13 point.
l l
14 CHAIRMAN HENDRIEs Go ahead.
15 COMMISSIONER AHEARNE:
When you refer to 197 16 throughout, I assume that we should be modifying that to say 17 197-Rev-27 18 MR. ROSS:
Right.
19
- 53. NATTSON:
Yes.
20 COMMISSIONER AHEARNE:
You ence referred to 0738, 21 is that really 0737?
22 ER. ROSS:
No, 0738 is the NUREG on the 23 qualification of equipment.
24 COMMISSIONER AREARNE:
You talked about detectors 25 for inadequate rote cooling.
ALDERSON REPCRTING COMP ANY,INC.
i 44 1
COMMISSIONER GILINSKYs Let's see, are we 2 finished, and going on to four?
3 ER. NATTSON:
Four is the analysis we were talking 4 about.
5 COMMISSIONER GILINSKY:
I see.
6 HR. NATTSONS Five and six, I thought I covered 7 them.
8 COMMISSIONER GILINSKY:
Can you tell me about the 9 matter of purging.
What it is this about purging and 10 repressurization systems in combination with external 11 recombiners, or whatever?
I did not understand tha t part of l
12 the c ale.
13 MR. MATTSON:
There is a large fraction of the 14 operating plants today that have no recombiners.
The set of 15 requirements here would say, for those who don't have 16 recombiners, that depend upon purge and the repressurization 17 of the containment to deal with hydrogen, to keep it from 18 burning under the old 50-44 rules --
19 COMMISSIONER GILINSKY Are we allowing purging?
20 MR. MATTSON:
The operation of current plants, 21 current tech specs would allow purging as a means to deal 22 with hyd rogen post-accident, yes, in large containnents.
23 COMMISSIONER GILINSKYs But you are not going to 24 get hydrogen without getting a lot of fission products.
l 25 MB. ROSS:
Commissioner Gilinsky, this goes back a l
l l
ALCERSCN REPCRTING CCMPANY,INC.
~
45 1 long way.
2 CHAIRMAN RENDEIE:
These purging provisions go 3 back into a time when few people beside me are old enough to i
l 4 have done that.
5 COMMISSIONER GIIINSKY:
No, I understand this is j
6 the post-accident problem, and the continuous generation of l
l 7 hyd rogen running off the valls, and so on.
8 CHAIRMAN HENDRIE:
The purging proposition just 9 - was that if you ever got out there some months down the line 10 to a place where you thought you were getting close to l
11 losing the containment on over pressuriration, that there 12 was a var to purge through filters.
There would be some l
13 releases, but they would be --
14 NR. MATTSON:
Tha t is the reason for requiring 15 number six, the hydrogen reccabiner capabilit.
It is i
l 16 because of the plants that have no hydrogen recombiners, l
l 17 either internally or externally, and would depend upon I
18 purging for long-ters hydrogen control.
l 19 A small group of people back in the Lessons 20 Lea rned days said:
"We ought not to allow that.
We ought l
l 21 to require them to have the capability.to hook up a 22 recombiner after an accident that they could obtain from 23 somewhere else."
24 So tais rule would require that that capability be 25 present at all plants that current depend upc 2 venting or ALCERSCN REPCRTING COMP ANY. INC, 1
46 1 purging, and repressurization in order to deal with 2 long-term hydrogen generation.
l 3
MR. CORNELL:
It is item VI on page 24.
I 4
COHNISSIONER GILINSKY:
Walk me through this.
You 5 would expect them to be able to deal with that_ hydrogen over 8 what sort of' period?
The recombiners cope with hydrogen 7 over a period of months, or something like that.
8 ER. NATTSON:
This is a long-term hydrogen control 9 from radiolysis or chemical reaction.
10 COMMISSIONER GILINSKY:
You are still talking 11 about that.
12 MR. MATTSON:
We are talking about the old kind of 13 hydrogen generation, not the new 75 percent hydrogen 14 ' generation.
This is a requirement that deals only with the 15 capability te deal with the 5 percent that was there before, 18 and a judgment by the staff af ter THI that reliance on a 17 purge over the long-term was not acceptable.
18 COMMISSIONER GILINSKY:
So you are getting away 19 from allowing them to --
l 20 MR. EATTSON:
Yes, giving them the capability to 21 acquire a recombiner to deal with long-term hydrogen.
It 22 wouldn't do you any good for the 75 percent and eight-hour 23 kind of probles.
It is not designed for that at all.
Then 24 the penetration business is to make sure that there are 25 reliable ways to use the recombiners to deal wi th the ALDERSCN REPORTING COMPANY,INC,
47 1 hydrogen externally to the containment.
2 COMMISSIONER GILINSKY:
Could you give me the 3 rationale for using the same figure for the-PWRs and the 4 BWRs?
In other words, using 75 percent of the clad as 5 opposed to the total amount of zircaloy in the core?
8 Let me ask it this way.
Is there a good technical 7 reason for. separating out the two kinds of zircaloy, or is 8 this a way of, so to speak, the BWRs credit for some better 9 expected performance, or lower ' likelihood of core damage, or l
10 whatever.
l 11 CHAIRHAN HENDRIE:
It prejudices the BWRs.
They 12 have got thicker cladding than the Ps.
13 MR. ROSS:
I think it is more metal water i
14 reaction.
15 CHAIRMAN HENDRIE:
It is scre hydrogen from the 16 same power capacity core.
i 17 COMMISSIONER GILINSKY:
Right, but there is still 1
18 yet another amount of hydrogen which is not being counted, 19 which is equal to the amount that is being counted.
20 CHAIRMAN HENDRIE:
Yes, but that is over in the 21 channel boxes.
I just don't think that you are going to get 22 them that hot.
23 COMMISSIONER GILINSKY:
That is what I am asking.
24
- 53. ROSS:
We talked about this a few months ago, 25 and I think we pointed out at th a t time that we didn't have ALDERSCN REPORTING COMPANY,INC.
48 1 a precise quantitative reason for the difference, any more 2 than we have a precise reason for the 75 percent in the 3 first place, as Roger said.
4 We are aware,that if the fuel rods heat up to the 5 point where they are significantly reacting, then for most j
6 scenarios the channel box isn't that far behind, at least in-7 the upper-part of the core.
Probably in the lower part of 8 the core, it is substantially cool, depending on the 9 scenario.
10 CHAIRNAN HENDRIE:
I just don't believe it, 11 Denny.
12 HR. ROSS:
Ue have data e-13 CHAIRHAN HENDRIEz The only var that that can be 14 true is that the water vapor content in the channel has to 15 be damn near dry, o the rwise the radiation f rom the rod will 16 be disappearing into the steam, raising the temperature of 17 the steam or converting water droplets to steam, and there 18 will be a Delta T of useful magnitude between the rod 19 surfaces and the channel boxes.
20 If yo u g e t' d ry, so the radiating transfer brings 21 the channel boxes up, so that it is all one dandy, glowing 22 mass, it can't have much metal water reaction going on, 23 because you haven't any H02 mass flow to make oxide with.
I 24 really think you have a lot of trouble taking the channel 25 boxers with you in the metal water in substantial degree.
ALDERSoN REPORTING COMPANY,INC,
~__
r 49 I
1 Tou get c. Little from contact, and so on but I just can't e
2 see it.
3 MR. ROSS:
I agree, Chairman Hendrie.
If we look l
l 4 backward and say that the f uel rods are substantially 5 reacting and consuming most or all of the water coming up j
8 from the bottom, and they are sitting at 2000 to 2500 7 degrees Fahrenheit.
If you start with that postulate, then 8 the channel boxes won't be far behind.
There is BWR flood 9 data to support it.
10 When you heat it up adiabatically, and you have 11 essentially no heat loss to the surroundings, the channel 12 boxes are n'ot f ar behind, it may be a few hundred degrees.
13 But the whole scenario is contrived in the first place to i
14 get to 75 percent --
l 15 CHAIENAN HENDRIE:
Yes, but all you need is a few 18 hundred degrees.
17 MR. ROSS:
That is true, i
18 CHAIRMAN HENDRIEa The rate constance is going 19 like this in this temperature range, and it is as soon as it 20 goes like this in the rods, and you have got the channel 21 boxes 200 degrees down from that, you are way down on the i
22 rate.
23 MR. ROSS:
That is true, which is, I think, the 24 original nativation of the staf f to discoun t the zircalo y l
25 from the channel box, because the geometry of the fuel rods ALDERSCN REPCRTING COMPANY,INC,
~
-~---
50 1 would be questionable at the time the zire would be, let's 2 say, at 2000.
I think clearly the circ would be a few i
3 hundred degrees behind.
t 4
HR. NATTSON:
Maybe we are trying to get down to l
5 too minor detail without the analyses to support it.
l 6
You will recall that in Sequoyah, we did only one 7 event sequence, and that is part of the reservation staff 8 continues to hold about the Sequoyah design, it is that more 9 sequences need to be evaluated.
We will do the same thing,
' hat we vill do it, to look at 10 and this rule in f act says t
11 more sequences for the Mark III reactor, and look at the 12 situation.
13 The judgment for applying the 75 percent equally 14 to BWRs and PERs is the judgment I said earlier -- beyond 75 15 percent, it becomes very difficult in either machine to 16 argue that you can stopped short of ceremelt.
This is to be 17 a rule designed for degraded cores, and not cocemelt.
18 COMMISSIONER GILINSKY:
Let me ask somebody else.
19 CHAIRMAN HENDRIE:
I have a better argument for 75 20 percent.
21 COEYISSIONER GILINSKY:
I want to hear it.
22 COMEISSIONER AHEARNE:
I would love to.
23 CHAIRMAN HENDRIE:
We have already had an accident 24 with upwards of 50 percent.
The argument is that for 25 regulatory purposes, you ought to at least cover that, that ALOERSCN AEPCRTING COMP ANY, INC,
i 51 1 is the lower bound.
The upper bound is 100 percent, and it 2 is damned hard to get 100 percent of everything.
3 If you set out to contrive an accident which would 4 give you 100 percent for zirc water reaction, I can 5 guarantee you couldn 't do it.
6 HR. MATTSON:
Corenelt, or anything.
T CHAIRMAN HENDRIE:
No matter how you set it up, 8 you couldn 't get it all to go..
So good, guess what, 75 9 percent is half-way in between.
It just has that great glow 10 to it.
11 COMMISSIONER GILINSKY :
That is terrific, but tha t 12 applies to PWRs.
In a BWR you just have a lot more 13 zircaloy, and you have got to make some sort of an argument 14 to ' segregate out the --
15~
CHAIRMAN HENDRIE:
My argument is that zircaloy is 16 at some distance from the hot oxide, which is the heat 17 source.
I i
18 HR. ROSS:
There are two sauces of information, 19 Chairman Hendrie.
When we look at the typical EWR ECCS 20 analysis, with only the top sprays working, and there is no l
21 bottom flooding, the heat transfer, until you turn around 1
22 the peak clad temperature is rod to rod radiation to the 23 channel box which is being cooled on the outside by spray, 24 Iypically, when the hot rod is at 2200, the i
1 25 channel box runs around 1350 Fahrenheit.
As soon as the ALCERSON REPORTING COMPANY,INC.
52 1 channel box quenches, and the quench front progresses from 2 top to botton as it cools off, the channel box drops to 3 about 700 or so.
Then very shortly thereaf ter, your clad 4 temperature vill turn around because it sees a much colder 5 source.
6 That is a terminated LOCA without significant 7 metal water reaction, except on the peak rod which had a 8 reasonable amount, maybe like 10 or 15 percent.
In tha t -
9 instance, there is about 750 degrees difference.
10 There are data, which I don't remember because 11 they are about 12 years old, on boiling water reactor fleck 12 test that are more extreme than this.
I don't recall that l
13 the channel box was deformed, but we would have to go back l
14 and look and see.
15 In order to do the calculations on the channel 16 box, we would probably have to pursue it with a program that 17 ve call our Sciere Accident Sequence Analysis, which we just 18 started, and I don't think we have any calculations along 19 that line.
20 I agree that where as you might react some of the 21 zircaloy channel box, for the accuracy that we are talking 22 about, 75 percent of the cladding is good enough for the 23 purpose that we are trying to protect.
24 COMMISSIONER GILINSKY:
Let me ask something 25 else.
Could you remind me what the significance is of l
ALCERSoN REPORTING COMPANY. INC.
~
53 1 leaving out in the calculation on containment response the 2 evaluation of instability?
What is it there that we are 3 leaving out?
This is page 21, right at the bottom.
Can 4 someone let me know?
5 MR. CASE:
My understanding is that it is the same 6 as the CP rule.
7 MR. FLEISHMAN:
It is the same as the CP rule, 8 that is where we got th words f rom.
The question is whether 9 it is right.
to CHAIRMAN HENDRIEs What is you are interested in 11 here is just that if you get these events going on -- Is 12 this one on the service level A?
13 MR. ROSS:
Service level C.
14 COMMISSIONER GILINSKY You are basically looking f
15 at the static pressure, but I can't remember what it was l
18 that was being left out here.
I hope that someone will give 17 me a call and let me know.
18 Let me go on and ask something else.
19 Is this program at Sandia leading to a standard, 20 is it designed to lead to a standard for environmental 21 qualifications of equipment that could be subjected to such l
22 burns?
Is that the object of the program?
l 23 MR. ROSS:
The best answer I can give you is that 24 it should be.
I just got acquainted with it yesterday, and 25 I don't know if Mr. Heats knows or not, but it seems like a At.CERSON AEPoRTING CCMPANY,INC.
54 1 reasonable purpose for an NRC sponsored program.
mod 730AI.*
2 MR. 221:S The main purpose of it is to develop 3 the predicted capability to predict what the temperature 4 transfer on those components is.
The criteria is something 5 that we have not really thought about.
It will have to come 6 along later.
7 COMMISSIONER GILINSKY:
Well, I think we had a better think about the standards that we are going to have l
}{0gjfh 10 MR. 503:3:
I think that it is a fair comment.
11 COMMISSIONER AHEARNE:
We are going to put a 12 deadline that is going to be before that.
13 COHNISSIONER GILINSKY:
let me ask you also, 14 without getting into the merits here, how does this process 15 of developing this rule factor in whatever may have been 16 developed in the Haguire hearing in which hydrogen control 17 is a contention?
18 5R. ROSS:
What we had in mind was -- In fact, 19 this is what the dates on items two, three and four are 20 slanted for.
The dates are all slanted towards the license 11 condition for both Sequoyah and, I guess sooner or later, 22 Maguire, if it is not already -- in particular the item two 23 and item four would be affected by additional analysis and 24 lookinc at other systems this year.
25 The discussion we had with the Commission on l
l ALDERSON REPORTING COMPANY,INC.
55 1 Sequoyah, we discussed to a small degree equipment 2 sury1vability.
The indication that the intent was that all 3 of the questions for Sequoyah and Maguire on two, three and 4 four get answered this year.
Now, in fact, whether they can 5 or not, I think, is questionable.
I am not sure we will 6 know all that it is needed to know on survivability on the 7 31st of January, anymore than we would know for D.C. Cooke.
8 CONNISSIONER GILINSKY:
I was not just thi.nking of 9 survivability.
I was just thinking about the functioning of to the hydrogen control system, the glow plugs, or whatever.
11 MR. ROSS:
I think the biqqest thing we learned in 12 a previous ice condenser experience is c.a item f our, that we 13 should broaden our analysis horiron, and look at a wide 14 range of scenarios.
That is what I would expect to happen 15 this year on ice condenser, and by implication on Mark 16 IIIs.
17 I am not sure how much more detail I can go into 18 without crossing the ex parte fence, but I guess you can 19 holler stop when you want.
20 COMMISSIONER GILINSKY Whatever is going on in 21 tha t hearing is not being ignored, and it is part of the 22 information base that you are working with.
23 MR. NATTSON:
Absolutely.
24 MR. ROSS:
A lot of the words that you see in the 25 statement of considera tion were re-written by the witnesses ALDERSCN REPCRTING COMPANY,INC,
56 1 at the Maguire hearing after they came back, to put in the 2 lessons they think they learned at the hearing into the 3 rule.
It is mostly on the analysis side.
4 MR. MATTSON:
One of the places that you will see 5 a test of this is in the next week or so, vrien we bring in 6 Sequoyah II.
The question we have asked ourselves is, given 7 what we have learned since Sequoyah I, would be change 8 anything.
The answer is, no.
But we vill be prepared to 9 give you the technical details of that -argument.
l 10 CHAIEMAN HENDRIEt Is "no" consistent with the 11 somewhat gloomy tone I find in the paper and in the 12 discussion this morning about these things?
13 MR. MATTSON:
Yes.
"No" is a view of those gloomy 14 words.
The gloomy words was to make sure that the 15 Consission understood that there are things that we need to i
l 16 continue to look at.
But the judgment still is that the 17 system is designed as well as we know how to design it at 18 the acaent, and that the eventual answer to these questions 19 vill be a positive answer, and that the system as designed 20 today doesn't detract from safety.
21 COMMISSIONER GIIINSKY:
I hope that it does more i
22 than that.
COMMISSIONER AHEARNE:
Let me ask a couple of 23 i
24 minor questions.
25 You have a statement on page 22 towards the Ai.cEasoN REPORTING COMPANY,!NC, l-
57 1 bottoa, which says, "Furthermore, inadvertent f ull inerting 2 aust be safely accommodated during normal plant operation."
3 I assume you mean safety in this sense must be accommodated 4 without brief of containment; or, do. you also mean that it 5 aust be able to be accommodated without harm to any workers 6 who might be inside of it?
7 MR. CASE:
The former, but more than just 8 containment.
It is just that it is necessary to keep the 9 reactor safe.
10 COMMISSIONER AHEARNE:
But by safely, you don't 11 mean to say personnel safety.
12 Then secondly, the last sentence of that 13 paragraph, I don't understand, and I would like someone to l
14 e xplain it to ne', what it means and why it is there.
15 MR. FLEISHMAN:
That was added mainly to take care l
I 16 of operating reactors, to point out that when they de 17 ins'all a hydrogen systen they have to supply analyses to 18 justify.
We were pointing out that it would be an 19 unreviewed safety qu es tio n.
20 COMMISSIONE3 AHEARNE:
But there is another 21 section of the rule that says, they must provide analyses.
l 22 MR. FT2ISHMAN:
I think so.
The section of the 23 rule that was addad on the analysis was modified after this 24 other thing was done, and I think this could probably be 25 taken out with no loss.
ALCERSoN REPORT 1NG COMPANY,INC,
58 1
We were just pointing out that it is a change to 2 50-59, and they have to do everything involved 3
H3. EATTSON:
Which means that they can 't 4 accomplish it unless the staff agrees with the design as 5 supported by the analysis.
It mora than just analysis.
6 They ha've to submit a piece of paper saying, "We want to do 7 this.
Can we amend our license to do it, or is our license 8 sufficient to cover this."
The staff has to give them an S affirmative go ahead before they can dc it.
10
- 53. EISENHUT.
It is unnecessary.
11 HR. NATTSON:
It is not nececsary?
l 12 COMMISSIONER AHEARNE:
The next question.
13 CHAIRMAN HENDRIE:
Wait, let's clarify where all 14 of that case out.
15 COMMISSIONER.AHEARNE:
Having been told that it is 16 unnecessary, I would drop ny question that I did not 17 anderstand it.
If it is not going to be there, then I don't 18 have to understand it.
l 19 HR. NATTSON:
We should strike that sentence 1
20 out.
11 CHAIRMAN HENDRIE:
Strike it.
22 COEMISSIONER AHEARNE:
Let me ask the last 23 question.
24 COMMISSIONER READFORD:
What have you struck, I am 25 sorry?
I ALOEASCN REPCRTING COMP ANY, iNC,
59 1
CHAIRMAN HENDRIE:
We are limiting this rule to 2 fast breeder Jeactors, light water reactors -- It is a 3 f airly minor change.
4 (laughter.)
5 COHNISSIONEB AHEARNE:
The number of additional 6 tasks that an operator would be required to do on these 7 a.dditional features that you are proposing plants put in. We 8 are continuing, it appears to me, a path which says that we 9 vill ask operators to be responsible for more and more to things early in an emergency, my general question is, that 11 at some stage is beitig folded into some understanding of, do 12 we-need mote operators, do we instead need to go to an 13 automatic system that the operator keeps his hands off j
14 during the first stage of emerge'acy; or do you feel that l
15 these additional things just aren't significant in 16 comparison to the number that he already has to do?
17 MR. ROSS:
Are you talking about the collection of 18 the items as a total?
19 COMMISSIONEB AREARNE. I as talking in particular 20 about any of these hydrogen control features?
21
- 53. MATTSON:
Yes, we have, because item 14 is 22 that point exactly.
we a' e no t talking 23 COMMISSIONER AHEARNE:
Item 14, r
24 about.
25 MR. MAITSON:
We were.
ALCERSCN REPCRTING CCMPANY. INC.
I i
60 1
COMMISSIONER AHEARNE:
No.
2 MR. MATTSON:
When we came in, we were.
3 Iten 14 is the thing by which the concern you 4 speak of is handled.
5 COMMISSIONER AHEARNE:
But, Roger, we are nov 6 addressing a proposed rule *. hat doesn't have anything in 7 that.
It has a proposal that we vill require the plants to 8 put in place these sitigation systems.
9 3R. ROSS:
On the ice condensers, we looked at the 10 procedure that required them to be implemen ted.
It, by 11 itself, was not a very complicated procedure.
s 12 COMMISSIONiR AHEARNE:
So you do not feel that 13 this additiohal level of --
14 MR. ROSS:
Taken tv itself, no.
I am not sure 15 that it is a fair way to take it, without looking at the 16 assembled average.
By itself, no, I think there is no 17 problem.
18 COMMISSIONER AHEARNE:
Using either the 19 post-inerting system, or the igniter system as you would 20 foresee it being installed.
21 MR. ROSS:
The post-accident inerting system, I 22 have not looked at.
I am not sure anyone else has looked at 23 it, other than conceptually.
24.
The operating factor there I think wiil be how 25 quickly can staff inside containment get out, given that the ALDERSON REPCRTING COMPANY,INC,
61 1
thing starts to actuate.
2 COMMISSIONER AHEARNE:
In your reexamination of 3 ice condenser ignition system, do you see the NRC position 4 in any way shif ting towards some of those proposals that 5 would require control of individual igniters, and evaluation 6 of the local conditions before using igniters?
7
~'
MR. ROSS:
I don't know.
In the audience, Les 8 Rubinstein or Walter Butler are closer to it than I am, for 9 sure.
I to NR. RUBINSTEIN:
At the current time, we don 't see 11 that kind of a logic being introduced.
It is one of the i
l 12 questions we have asked TVA and other owners to address, but i
i 13 we don't sae it.
I think it is early on, and on throughout, f
14 it is going to be the answer.
15 COMMISSIONER AHEARNE:
Those are all my 16 questions.
17 CHAIRMAN HENDRIE Peter?
18 Vic?
l l
19 COH5ISSIONER GILINSKY:
I have exhausted myself on 20 the hydrogen issues.
21 CHAIRMAN HENDRIE:
All right, let me pick up some 22 matters.
l 23 First of all, let me go back to this question of 24 cutting on the rule.
You managed to slip out of the room 25 before I inquired for a division of the house, Peter.
ALDERSoN REPORTING CCMP ANY. INC.
62 i
1 If you look at this list, which is fortunately i
2 still up on the slip, the first six items have a lot to do l
3 hydrogen control and the others are a miscellaneous group of 4 things that are also now before us in the draft of the 0737 5 rule.
6 Ny strong ir.clination, if we are to have an interia 'ydrogen control rule, is to make it an interis h
7 8 hydrogen control rule, and cut off seven through 14, and let 9 those be considered in the context of the other paper that 10 we have.
11 They are a miscellaneous array of various 12 Short-Tern Lessons Learned items, many of which are in 13 current implementation, processes of implementation, I 14 believe, on operating reactors on an order basis.
True?
15 HR. CASES Parts, some of them are out in time.
16 We have not gotten to the order type approach yet.
17 CHAIRNAN HENDRIE:
That is one proposition that I 18 would make to you.
19 The second is that I would propose that just i
20 points one through six, as amended by this morning's 21 discussion, ought to go out for another round of comment.
22 Hydrogen control is a subject that is not precisely strange 23 to the people who are likely in a position to be able to 24 consen usefully on the provisions here.
I would think that 25 it could be a fairly short comment period.
ALDER $0N REPORTING CCMPANY. INC,
1 63 1
That is sort of the approach I would take to it.
2 John, I think, would pref er to go with all 14, although he 3 would not be adverse to considering Rule A with one through 4 six, and Rule B with seven through 14 5
COMMISSIONER AHEARNE:
Just as a reminder or a 1
6 f oo tno te.
I said I wanted to include seven to 14 I did 7 not say that I would to include one through in.
8 CH AIRMAN HENDRIE4 Vic was willing to split it.
9 When-I looked at your seat, you had gone.
Jo I used your to absence to use a two-one victory for my point of view, at 11 least with regard to the discussion which has then gone on l
l 12 for the last hour.
But now, as ve come back to say, what 13 should we do with this draft, which is before us, you will t
14 get a chance to get your vote in.
15 COMMISSIONER BRADFORD:
I am all for rulemakings 16 that are confined as much as possible to a single more or l
17 less coherent subject, so you will have no difficulty with 18 se there.
19 I don't oppose going out for another short comment 20 period on the hydrogen items themselves.
I would rather not 21 close completely on what goes out this morning.
If you can 22 stand that, I would like to spend a little more time 23 puttering through it.
I had not realized, and in fact I am 24 not sure now that you are actually willing to vote it cut at 25 the table here.
But I have no objection to the split in ALCERSON REPORTING COMPANY,INC,
~
64 1
principle.
2 COH5ISSIONER GIIINSKYs John doesn't disagree with 3 going out, or do you?
4 COMNISSIONER AHEARNE:
I would be violently 5 opposed to approving one through six as a final ~ rule.
I 6 have no difficulty with going out for comment on one through
-7 six.
8 C05HISSIONER BRADFORD:
What is it about one 9 through six that you would not approve. if that '. ; what we 10 were doing?
11 COMMISSIONER AHEARNE:
I have a lot of problems 12 with the logic that has led us to one through three.
13 COMMISSIONER GILINSKY:
let me ask another 14, question.
l 15 Why would you not put seven in this category?
It I
i 16 seems to me that while it is true that it also applies to 17 other non-condensables, the real plan of it was dealing with l
18 hydrogen, and that is the write-up in the Action Plan.
It l
l 19 is almost entirely devoted to the hydrogen problea.
It 1
20 seems to me that they go together as a set of means of 21 dealing with possible generation of hydrogen.
22 You said that it was a hardware item, which may 23 mean you want to have a different implementation schedule.
24 But it seems to se tha t it logically goes together.
25 MR. MATTSON:
You can make argument that it goes i
ALDER $oN REPORTING COMPANY,INC,
65 I with others, too.
There are some designs that propose some 2 coupling between number seven and number 13, for example.
j 3 But that is no stronger argument than the argument I gave 4 you earlier about seven includes nitrogen and not just i
5 hyd rogen.
l 6
CHAIRMAN HENDRIE:
I don 't know that I have any l
7 argument of sweeping brilliance to dc==le you with.
8 COMMISSIONER GILINSKY:
I thought your point was 9 that it being a hardware item, we would not be pressing as 10 hard on it.
11 CHAIRMAN HENDRIE:
It has been one of those 12 continued to be argued -- One of those hardware items that 13 continues to be argued.
It sort of strikes me as one of 14 those pot and pipe primary system sort of things, and I 15 quess in looking at one through six, I am looking to trying l
16 to stay up on the containment systems.
l 17 COMEISSIONER C-ZLINSKY :
Are we telling people now 18 to put those things in, or are reactors in the course of l
19 putting them in?
20 MR. CASE:
They a re in the course of designing 21 them and trying to figure out schedules.
22 requires them on OLs and ors.
23 HR. EISENHUT:
Yes.
In fact, all but seven l
l 24 licensees have given us a commitment that they are going to 25 be putting them in on some consistent with NUREG-0737.
They I
ALCERSoN REPCRTING COMPANY,INC,
66 1 are really coupled, as Roger said, the reactor water level 2 instrumentation, sed a number of othat instrumentation in 3 some of the other pieces.
Since they require shutdown, ther 4 are trying to couple them with the other hardware fixes that 5 go in, or that have to be put in.
6 Tha point being, and I think Denny made it several 7 times, a piece of using the reactor coolant best, is you 8 vant to have the reactor water level indication, etc., etc.
S Tou can't really use the vents without having some other 10 pieces that go with it.
11 MR. MATTSON:
The consistency of the package you 12 are trying to put together is hydrogen control and 13 containment, where the number sevan really deals with 14 hydrogen la the reactor.
15 COMMISSIONER GILINSKY All right.
16 CHAIENAN HENDRIE:
That is better than I could I
17 have done.
~
18 CCMUISSIONER GILINSKY:
They picked up pretty l
19 fast.
20 CHAIRMAN HENDRIE4 2 age 7 of Enclosure C, you are 21 carrying on here about the new paragraph that has been added 22 about Mark IIIs, and ice condensers.
23 COMMISSIONER GILINSKY:
Could I ask a general 24 question about the rest of th a t list?
25 CHAIRMAN HENDRIE:
Yes.
ALDERSoN REPCRTING COMPANY,!NC,
. -,.~,.-.- -..._..
f 8
67 1
COMMISSIONER GILINSKY:
In selecting out this list 2 for rulemaking, were you saying that these are things that 3 are more important than what is left in 07377 4
COMMISSIONER AHEARNE:
0737 has not been written.
5 MR. MATTSON:
No, that was not the logic.
The s
6 logic was that these were the things that went beyond the 7 design basis.
These were the degraded core and coramelt 8 considerations in the Action Plan.
The attempt was to try 9 to decrease the amount of controversy over how far is f ar 10 enough to go into that reals, pending.the long-term 11 rulemaking.
12 So the thought was to car te out all of the things 13 that went beyond the 5 percent metal water, appendix K, all 14 of the traditional design basis.
15 CHAIRMAN RENDRIE:
That is not the way I would 16 define seven through 14 17 MB. MATTSON:
The traditional design basis is l
l 18 Appendix K, it is the most limiting event.
19 CHAIRMAN HENDRIE:
But you have got some things in 20 0737 that are not in that list that fall precisely under the 21 description you just gave.
Similarly, I think some of these 22 things are not of that character.
[
23 MR. MATTSON:
Once upon a time, that was the 24 judgment.
25 COMMISSIONER GILINSKY:
That was the idea, in t
l ALDER $CN REPORTING CCMPANY,INC,
~
68 1 other words.
2 CHAIRMAN HENDRIE But these things are there 3 because these were identified fairly early out of the 4 Short-Tern, primarily out of the Short-Ters Lessons Lectned, 5 and they were the sort of things that you were pushing at s l
6 time when the Action Plan had all that firmly settled.
7 MR. MATISON:
When this was going to be an 8 immediately effective rule, and was going to go out in a
- t 9 month, and things like that.
10 CHAIRMAN HENDRIEt Yes.
11 MR. MATTSON:
Yes, but a lot of water went under 12 the bridge.
13 COMMISSIONER GILINSKY:
This was sort of the 14 interim degraded core rule.
15 CHAIRMAN HENDRIEs Yes.
l 16 COMMISSIONER GILINSKY:
What sort of a schedule 17 are we on for turning 0737 or parts of it into a rule?
I 18 MR. MATISON:
You have the Commission paper in l
19 front of you on 0737 to make it a rule.
20 COMMISSIONER AHEARNE:
Does it pick up moving all l
21 of this out of this rule and into it?
l 22 MR. MATTSON:
They are in both.
l 23 COMMISSIONER AHEARNEs I thought thic was written 24 towards all applications.
25 MR. EISENHUT:
Two things.
The one that we l
l l
ALDERSON REPCRTING COMP ANY, INC,
i o.
t 69 1 proposed and sent downtevn addressed only OLs.
It included, 2 on these nine items, the identical words.
They were both 3 working in parallel to the same day, but we tried to keep 4 tne exact same words, which was the intent.
5 I believe Tuesday there is a meeting set up with 6 the Conaission, and at that time, coupled with what we are j
1 7 saying here today, we would be proposing turning that 8 document that you have into an OR plus OL rule.
S COMMISSIONER AHEARNE:
In other words, what you i
10 are saying is that you would change this?
11 HR. EISENHUT:
Yes, because the majority of 0737 l
12 items are technically the same items.
1 13 COHHISSIONER GIIINSKY:
So we would be turning to l
14 the rest of this f airly soon.
15 ER. EISENHUT:
Yes.
16 CONNISSIONER GILINSKY:
Almost immediately.
17 CHAIRMAN HENDRIE:
Yes.
18 ER. BICKWIT:
We suggested that the Commission 19 might be ready to consider that at next Tuesday's meeting.
CHAI'RHAN HENDRIEs It is a matter -- You and I 20 21 have been interested in this interim hydrogen.
They came 22 down about the same time, maybe the hydrogen was a day or 23 two ahead, but if you and I had been more interested in this 24 one than the one, this meeting could as well have been on l
25 0737.
l I
l i
l ALDERSON AEPORTING COMPANY,INC,
~.
)
70 1
COMMISSIONER GILINSKY Good enough.
2 CHAIRHAN HENDRIE:
Then I could have argued that 3 those itees did not need to be considered because they come 4 up in the hydrogen control rule.
5 Back to page 7, when I get down to the bottom, the 6 distributed igniter system has been found to be acceptable 7-for the Sequoyah plant, but only as an interim solution.
8 The post-inerting system has been discussed.
Whatever 9 systems are finally proposed and are approved for the 10 long-tera --
11 -
If the Sequoyah solution and the post-inerting 12 that we have written into the proposed' CP rule are as 13 tentative as that sounds, then I am not sure I want to be up 14 here with an interim rule.
It seemed to me that in 15 Sequoyah, and the discussions on the CP rule about the 16 post-accident inerting, we had what looked as a reasonable 17 interim solution for these intermediate volume 18 containments.
19 It seemed to me, and I think that your feeling was 20 t he samt, that tells us something reasonable to do about i
21 hydrogen pr,otection f or this class of containnent.
Let's go 1
22 ahead and lay on the ones we have got out there.
23 Now, if it is all very uncertain, and at the end l
l 24 of this year, why a lot of different things are going to get l
l 25 done and backfit to Sequoyah, and so on, I don't want to go l
ALDERSON REPORTING COMPANY,INC, l
i
\\
l l
71 l
1 ahead now with putting things on a lot of other plants.
So l
l 2 I think you have to tell me just what the circumstance is 3 for you to do that.
I 4
let me tell you what I am looking for.
5 (Laughter.)
6 CHAIBRAN HENDRIE I am beginning to read into t
7 this rule some things that worry me.
I regard this as an 8 interim solution for a problem which we have, both a safety j
t l
9 problem and a regulatory.
10 The safety problem is that the plants ought to be
~
\\
11 a little better prepared to handle a chunk of hydrogen, if l
\\
12 they should get it.
The regulatory problem is, we need 13 something we can point to that says they do that, and
'hc atomic 14 therefore we are meeting the requirements of c
l 15 Energy Act.
1 16 Now, I don't expect the solution now in hand or 17 going ahead to cover every scenario and every circumst ance 18 that somebody could think of.
I think what is reasonable to 19 look for at this time, and in fact the general proposition 20 in regulation, but particularly in this problem at this 21 time, is a way to deal with hydrogen which gives reasonable 22 assurance that in a large fraction of the accident scenario, 23 you have'got protection, and the things will come out all 24 right.
25 I don't think I need, and I don 't think the system ALCERSON REPORTING CCMPANY,INC.
72 i
1 is capable of producing a hydrogen control system that is 2 proof positive against every damn possibility in the world.
3 That is not required.
Adequate protection doesn't mean zero 4 risk with regard to hydrogen or anything else.
5 So, indeed, there are going to be scenarios that 6 rou can put together where you get longer burns, or faster 7 evolution, or something like that, and maybe the Sequoyah 8 igniters, or the proposed CO2 post-accident inerting won 't 9 catch it.
That is the real world, I am sorry.
10 Our aim is to make those of low enouch probability 11 to make sure that those are only scenarios that are of 12 really low probability and just are below the safety level l
13 thTt we have come by practice to establish an adequate 14 protection.
l l
15 It has seemed to me that the Sequoyah, that the 16 igniters, on the one hand for sure, had that 17 cha racte ristic.
It seemed to me from the discussion on the i
1 18 CP rule that the post-accident CO2 inerting probably had 19 that characteristic.
l 20 Now, you have a paper before me, which you at l
21 least a while ago were willing to make final because that is l
22 the language that it came up with, which says, "Well, we are l
23 still working on it.
We are not sure what the final l
24 solution will be.
We prefer not to burn," and so.
I can't 25 buy it in that form.
ALDERSCN REPORTING CCMPANY. INC.
73 1
You have to tell me whether it meets my reasonable 2 protection for the majority of hydrogen evolutions 3 scenarios, or it doesn't.
If it does, let's come away from 4 this shilly-shally wording in here.
If it doesn't, let's go, 5 back to the drawing board, and we will think about a 6 hydrogen rule in a year.
7 COMMISSIONER AHEARNE:
Could I make a comment?
8 CHAIRMAN HENDRIE:
Yes, sir.
9 COMMISSIONER AHEARNE:
I found no problem with the 10 sta ff 's wording, because it appeared to me that they had 11 incorporatad into the rule some features for requirements 12 that, as has been pointed out already this morning, were not 13 there originally.
I felt that it accurately represented the 14 level of knowledge we have on a lot of this phenomena, and I 15 think the discussion this morning has shown tha t there are a i
16 lot of questions that still have to be explored and 17 understood.
18 I think this certainly represented what I felt to 19 be as far as we could go on saying how positive we are.
l 20 HR. ROSS:
Chairman Hendrie, did you want a 21 response from us?
22 CHAIRMAN HENDRIE:
I don't know.
What I am saying 23 is that I am not going to vote to put this rule out for 24 comment, or anything else, until I understand where the l
l 25 staff stands.
ALCERSoN REPORTING CCMPANY,INC,
74 1
MR. MATTSON:
Can I tell you what the words meant 2 to us?
3 The words were primarily intended to not foreclose 4 the consideration of post-accident inerting by the long-term i
5 Mark III containment owners.
We think that there is a need 6 to continue to consider alternative hydrogen mitigation 7 schemes in the Mark III.
That is primarily the reason for 8 that language, that tentative language.
9 Insofar as the ice condensers are concerned, our 10 expectation is to give long-term approval to th ice 11 condensers next January, once the research and the on-going 1
l 12 analysis turn out the way we expect them to turn out.
They i
13 sight not, but we expect them to turn out to provide a basis 14 for long-tars approval for the igniter for the ice 15 condensers.
to The tentativeness is there for the Mark IIIs.
17 COMMISSIONER GIIINSKY :
Why is that?
18 MR. MATTSON:
Because we have not seen any design l
19 yet for the Mark IIIs.
The igniter system was just 20 submitted.
We have heard from some Mark III owners the l
21' consideration of post-accident inerting, which looked like a i
22 pretty good system when we heard it, and now we see that the 23 first two Mark IIIs have opted instead for ignitions 24 systems.
25 It may be th a t they have a good technical reason
(
l ALCERSCN REPORTING COMPANY,INC.
75 1 for that, but back in regulatory space, as Dr. Hendrie 2 described it, we would not want to see a precipitous move to 3 igniters on the part of the Mark III simply for regulatory 4 reasons.
We want to continue to make them do analyses of 5 the analyses for the Mark III design.
6 We are not near as tentative on the ice condensers 7 design.
8 COMMISSIONER GILINSKY:
Why do you distinguish 9 between the ice condensers and the Mark IIIs?
10-MB. NATISONs We would have to get into the 11 technical details of why the Mark IIIs think they can handle 12 post-accident inerting, while the ice condensers thought 13 they couldn't.
That is the reason.
14 We thought people made a pretty goci story fo r 15 post-accident inerting of the Mark IIIs.
l 16 COMMISSIONER AHFARNE4 When they came in for cps?
l 17
- 53. MATTSON:
As an owners group, they came in and l
l 18 talked about what they thought they could do for their l
19 containment for this problem.
This was before I came back.
20 COMMISSIONE3 GILINSKY:
Ir seems to you that that 21 may be a be tter solution for the Mark III?
l 22 MR. MATISON:
Yes, at least for the steel 23 containment Mark IIIs.
We are told, and we have not 24 reviewed it yet, that that is not the right approach for the 25 concrete Mark IIIs.
ALCERSCN AEPCRTING COMPANY. INC.
76 1
COMMISSIONER GILINSKY let me ask you another 2 way.
Does the distributed ignition system work less well in 3 the Mark IIIs; is there a problem with it in the Mark IIIs 4 that there is not in the ice condensers?
5 MR. MATTSON:
We are not saying that.
We are not 6 saying that we see problems with the distributed ignition 7 system in the Mark IIIs.
8 COMMISSIONER AHEARNE.
You have not analyzed it.
9 MR. MATISON:
That is right.
10 COMMISSIONER GILINSKY:
But you think that th e 11 other one may be a better solution for the Mark IIIs?
12 MR. MATTSON:
Yes, or some Mark IIIs.
13 COMMISSIONER AHEARNE:
The inertinc really had a 14 lot of simplicity in it that the igniter system doesn't.
I 15 recall the inerting did not seem to be an acceptable 16 approach for the ice condensers because of the strength of 17 the containment.
i 18 MR. ROSS:
Let me explain some of the uncertainty l
l 19 that was in the mind of the staff on the analysis side, 1
l 20 which is coupled.
l i
21 The single scenario that was studied on the ice 22 condenser was the small break loss of coolant accident with 23 failure of the pumped injection system.
When you make that 24 assumption, then you get a certain steam release to the 25 containment and a certain hydrogen release when it ;ets het ALOERSON REPORTING CCMPANY,lNC,
77 1 enough.
2 Those analyses will tell you, as you follow the 3 steam and the hydrogen around from place to place in the 4' con tainment, whether there is enough hydrogen air mixture to 5 support burning, and if there happens to be enough steam to 6 preclude burning, the so-called, steam inerting.
But most 1
7 of the attention on the efficacy of the igniters was on that j
8 single scenario.
l 9
At our request, and I think we explained this to l
10 the Commission last January, Brookhaven extended the i
f 11 calculations to less likely scenarios that at points in the 12 evolution of the accident gave out more water, which 13 vaporired, being hot, and could from place to place in the 14 containment create steam inerting.
We thought that 15 transient was extremely unlikely, and said so.
16 But there have not been, but just a few, perhaps 17 one or two scenarios studied in detail.
What we had in mind 18 was to postulate a few other degraded core sequences, more 19 than just one or two, and certainly less than 100, probably 20 fewer than 10, and calculate whether steam inerting, which 21 is I think the great villain of the distributed ignition l
22 system, might be a predicted to occur for long periods of 23 time, such that you would not burn when you thought you 24 would.
25 That is the main analytical study to be done this ALDERSON REPORTING COMPANY,INC,
78 1 year for ice condensers.
None of it, to my knowledge, has 2 been done at all for the Mark IIIs.
When one postulates the 3 various degraded core events, and follows the steam and 4 hydrogen release, one might well calculate steam inerting 5 there also, in which case the distribution ignition might 6 not work so good.
The work is just not done yet.
l 7
I don 't think tha t this is a f atal flav to issuing 8 the rule, or recirculating it f or comment, because we 9 believe, and it is our judgment, that the small break 10CA 10 with no ECCC, the so-called S-2D sequence, is the most 11 likely sequence of those that are going to generate 12 hydrogen.
For that, the ignition system is believed to be 13 fine.
14 When you look at the next most likely sequence, it 15 is var down on the list, and I would expect to exclude 16 sequences on probability altne.
17 CONNISSIONER GILINSKY Can you tell me why you l
18 can 't use the post-accident inerting in the ice condensers 19 case?
20 HR. ROSS I think Charlie Tinkler is probably the 21 best one to answer that.
22 MR. TINKLER:
The major reason that I personally 23 see why ice condensers would not prefer post-accident 24 inerting, it might be a combination of design pressures, and 25 the fact that inadvertent opera tion of a po st-a ccid e n t ALCERSON REPORTING COMPANY,INC,
... ~
79 1 inerting system could have fairly serious consequences on 2 the maintenance of the icebed itself, which face sublimation 3 problems now.
4 Post-accident inerting, the inadvertent operation 5 of that kind of system would probably cause some serious 8 problem as f ar as the maintenance of the ice mass in the 7 icebed.
I am sure they have design preferences from the 8 point of ignitors also.
9 COMMISSIONER GILINSKIs I thought, from our to discussion of the Mark III, when we were talking about the 11 CP rule, we just generally felt a little better about the 12 Mark III than the ice condensers; is that a correct 13 impression I walked away with?
l 14 MR. ROSS:
I am not sure vtat the suestion is.
I 15 COHEISSIONER AH2ABNE:
They also came in that is 18 the owners group, strongly pushing the inerting.
17 NR. ROSS:
They had two concepts on inerting,
~
18 either halon or CO2.
I think that that is the only thing 19 tha t they were really interested in from their viewpoint.
20 COMMISSIONER AHEARNF:
And that avoid a whole host 21 of these other problems.
22 MB. NATISON:
You don't have the pressure problems.
23 COMMISSIONER AHEARNE:
Yes.
24 MR. MAITSON:
If you have got the pressure 1
25 problems like the ice condensers or the concrete Mark III ALDERSCN REPORTING COMPANY. INC.
80 1 apparently do, then you are forced back to the burning 2 system.
3 COMMISSIONER GIIINSKY The pressures in the two 4 containments are about the same.
I am surprised that that 5 would be a factor.
6 ER. MATTSON:
The design pressure?
7 CHAIRMAN HENDRIE:
Why do steel Mark IIIs come off 8 easier than steel ice condensers with regard to 9 post-accident inerting pressure considerations?
l-10 HR. MATTSONa I thought the answer was the degree 11 to which you can go beyond the ' design pressure and prove l
12 functionability.
i i
13 MR. RUBINSTEIN:
The far-out Mark IIIs would take 14 some steps to strengthen their containment, and allow then 15 to get up to around maybe 37.5 to 39 psi.
The proposed 16 change is between the base-plate and the point where the 17 right circular cylinder joins it, and a few other changes.
18 I*.
is the near tern Mark IIIs, like Grand Gulf, l
19 which find the igniters rather attractive.
20 CHAIREAN HENDHII:
So it is not a question of 21 steel or =oncrete.
It is'a question of whether the damn 22 built to the design pressure of 15, or whether it it not 23 built, and they still think they could beef it up and up the 24 design pressure.
25 MR. RUBINSTEIN:
That is true.
I think you need ALDERSCN REPORTING CCMPANY,!NC,
81 1 that, because you get up in the regime of about 17 to 19 psi 2 from the CO2 injection.
3 CHAIRMAN HENDRIE:
That is vnat I thought.
It 4 seemed to se that I recalled something like 22 pounds of 5 gauge after full discharge for at least one of the Allen 's 6 Creek case.
7 3R. ROSS It is 10 for halon, and 22 for CO2.
8 MR. RUBINSTEIN:
We have nothing negative to add 9 or positive in terms of igniters on Mark IIIs.
We have just to got the submittal, and we are looking at it, so I would not 11 vant to prejudice igniters in the Mark IIIs either.
We just l
12 don't have a statement to make on it now.
13 CHAIRMAN HENDRIE What would you propose to do?
14 Suppose we wanted to go out for comment on the hydrogen part 15 of this thing, what would you to do with these January 31, 16 198 2, dates.
I take it you want to put dates in 17 MR. CASES Darrel has got the answers.
18 MR. EISENHUT When you give me specific 1
19 questions.
20 We basically propose modifying somet':.ing along th e 21 lines of what I went through when we were discussing item by 22 ites.
Basically, some are a year.
For exanple, Mark I and 23 Mark II, we would go to six nonths after the OL for OLs.
24 For ors, we would stick with the 1-1-82.
25 CHAIRMAN HENDRIE:
Could they do it by 1-1-827 ALCEASCN REPCRTING COMPANY,INC,
82 1
NR. EISENHUTs That is a very good question.
2 There are only two out there that are operating.
We have 3 asked them repeatedly, and at worst it is 10 months away, or 4 something, on one plant; and 10 days away on the other 5 plant.
It is close enough, and what we would propose is to 6 stick with the dates, and ask everyone to go ahead and try 7 to give it a good shot.
8 There are only the two plants.
One utility has 9 told us that it is 10 months away.
The other one says that 10 the minute we require it, they can do it in a very short 11 timeftase.
They have everything they need.
12 MB. CASE:
Except the nitrogen.
13 CHAIRMAN HENDRIE:
That is because they came along 14 at a time when they thought they were going to inert, and 15 they planned to inert.
They put a lot of gear into inert.
j l
16 Then the '/ersont Yankee case came up just in time, so they f
17 didn't have to buy a load of nitrogen and inert.
18 MR. EISENHUT.
That is right.
19 CHAIRMAN HENDRIE:
Whereas the other guy has to 20 start f rom scratch, and his date probably is right.
21
- 33. SUTLIR:
I would like to make one point with 22 respect to the other guy.
That would be Ha tch II.
I had 23 word that Hatch II was going forward and implementing the 24 inerting provision ahead of time on a voluntary basis.
25 MR. IISENHUT Yes, they are just basically ALDERSoN REPORTING COMPANY. INC.
83 1 vaiting effectively to go ahead and put it in ;isce, for us 2 to say that we have got a rule and we want it in place.
3 They are perfectly volunteering to go ahead and do it.
4 COMMISSIONER AHEARNE:
If they are perfectly 5 volunteering to go ahead and do it, why don't they go ahead l
l 6 and do it?
l l
7 MR. EISENHUT:
I think they are, it is just a
~
8 matter of time.
l 9
COMMISSIONER AHEAENE:
We would not prevent thes i
l 10 from doing it.
l l
11 MR. EISENHUT:
No, we certainly wouldn 't.
In I
l 12 fact, we would say,~as soon as practical, put it in, but no 13 later than this date.
That would be the intent.
14 CHAIRMAN HENDRIE:
Since you have only got two 15 reactors, and the one guy is going to go ahead and do it, 16 and the other one says that it will take 10 months or so.
17 When does Vermont refuel?
18 MR. EISENHUT:
I don't have the date here.
They l
19 argue that there are equipment problems.
They are apt to be 1
20 getting equipment in.
l 21 CHAIRMAN HENDRIE:
They have to do a lot of stuff, l
22 vell, some stuff, start pipe and other stuff.
Why don't you 23 aake it start up after refueling shutdown, if one comes at a 24 reasonable time.
l 25 MR. EISENHUT:
What we propose here is if we vent 1
ALDERSoN REPcRTING COMPANY,INC,
84 1 in with a date during the comment period, we would ask the 2 two utilities to give us their commitment as to when ther 3 can get in, and show us that they really have to do from 4 between here and there, to come up with such a day.
5 CHAIRHAN HENDRIE:
The analyses?
6 ER. EISENHUT4 The analyses we would be proposing,
- 7 that is the one I think we would come up (inaudible)--
8 CHAIB5AN HENDRIE Instead of six months?
9-HR. EISENHUT:
Instead of six months for the PWRs, 10 we would be saying two years from the effective date of the 11 rule.
The equipment survivability was the other one.
We 12 would delay the 1-1-82 to 1-1-8 3. -
13 ER. MATTSON:
How do you do equipment 14 survivability without the analysis, Darrel; that was a 15 glitsch I' thought I saw before.
Maybe that would have to be to after the analysis.
17 MR. EISENHUTa The discussion before was confusing 18 on analyses.
There are several parts to analyses in the 19 rule.
The actual words, I' believe, are tha t you have to be 20 able to show that you can safety shut down the plant and 21 maintain containment integrity.
There has to be a subpart 22 of that done before the EQ rule, but the overall package 23 would be --
24 COMMISSIONER AHEARNE:
The systems have to be 25 shown to be capable of performing their functions.
ALDERSoN REPCRT1NG COMPANY, INC.
85 1
HR. EISENHUT That is right.
2 NR. HATTSON:
I think it has come out in the 3 discussion this morning that there aren't any criteria for 4 survivability.
It is going to be very difficult to just jaa 5 survivability down a large number of dry PWR containments.
i 6
HR. EISENHUTs We specifically have asked the 7 industry for comments.
The approach it sounds like you are 8 discussing would be giving them the option to come back 9 firmly on what they can really live with in the industry.
10 COMMISSIONEH BRADFORD:
The rule itself does not 11 even use the word " survivability," or " survival," or
~
12 anything like that.
So what you are really talking about 13 a re the criteria for demonstrating capability of performing 14 their function.
I
~
CHAIRMAN HENDRIE:
When you talk about 75 percent 15 16 reaction for a range of time periods up to eight hours.
t 17 Fros what to eight hours?
18 MR. ROSS:
On page 23, in the middle of the page, 19 it says, "after the start of an accident."
I agree that 20 could --
21 COMMISSIONER GILINSKY:
What is assumed about the 22 release rate of that hydrogen to the containment?
23 HR. ROSS:
From what you read in the rule, you 24 can't get it.
The thing is, once you postulate a degraded 25 core sequence, you can.
For example, the traditional ALCERSCN REPCRTING CCMPANY,INC,
86 1 sequence of transient loss of all feedwater, you do a 2 calculation and the hydrogen comes out at a precise time in 3 the calcula tion.
So you would follow the sequence.
4 MR. MATTSON:
The intent is to be mechanistic 5 about the release.
6 COHEISSIONER GILINSKYs If you created hydrogen in 7 the cooling system, you could then release it at a ra te 8 which is just determined by the size of whatever opening you 9 have.
10 MR. ROSS:
That is true.
In fact, the sequence I 11 just mentioned, the so-called TMLB prize sequence, releases 12 hydrogen at a markedly different r' ate than the 52D sequence 13 does.
So you have to decide, based on analysis, and 14 including probability, which of the sequences you want to 15 postulate and the hydrogen will come out however it comes 16 out.
l 17 MR. MATTSON:
But the true sequence is the yield, 18 the production of 75 percent metal water reaction in less l
19 than eight hours.
You don't choose sequences that do it 1
20 over days.
21 COMMISSIONER GILINSKY:
'd h a t Joe was asking, if
{
l 22 you reAease this hydrogen in a very sho rt time, then you are l
23 putting a lot more stress on the control systems than you 24 would otherwise.
25 MR. ROSS:
Thtt is true, and that is why we were l
ALDERSoN REPCRTING CCMPANY,INC,
87 1 suggesting that this year, or however long it is, we should 2 explore more than just the S2D sequence.
3 H,R. HATTSON:
There aren't any sequences that 4 release 75 percent metal water reaction hydrogen in two 5 minutes, so why would you postulate it in two minutes.
The 6 intent is to be mechanistic about how the hydrogen can get 7 there, rather than arbitrarily or non-mechanistic.
8 COMNISSIONER GILINSKY:
I am not sure we are on 9 the same track here, but however you form the hydrogen, even 10 if the hydrogen is formed over some period of time, hours, 11 rou might possibly release it in minutes.
13 COMMISSIONER GILINSKY:
Was that taken into 14 account in your sequences?
15 MR. HOSS:
It should be.
I say it should be, but 16 we don't have a list of analyses that are excluded and 17 required.
A good example of what you are talk
.g about is 18 THI af ter the relief valve was closed, and then the 19 subsequent hydrogen release occurred whenever the operator 20 opened the valve.
If he didn't open it, or if he didn't 21 lift the safety valve, or something, it did not come out.
22 Things like that will be occurring in the various 23 sequences, and every time an opening a ppears, it could let 24 the hydrogen out.
25 COMMISSIONER GILINSXY:
It seems to me the ALDERSoN REPCRTING COMPANY,INC,
88 1 question to ask is simply how fast can hydrogen get out of 2 one of the valvas.
3 MR. MATTSON:
You do.
In the sequence, if the 4 valve opens, you place some probability on it.
If it is a 5 significant sequence, then you consider it and look at the 6 rate of discharge.
7 COMMISSIONER GILINSKY:
You said, if the thing 8 can 't be released in a certain period.
I thought you meant 9 really generat?d.
But when you say, released, you mean 10 released into the containment through one of the openings?
11 HR. MATTSON:
Sure.
The sequence includes all of 12 the steps in getting the hydrogen from inside the vessel 13 into containment.
14 NR. ROSS:
I see what you mean.
The release is
'5 fror two places.
From the core to the system, and from the 16 primary system into the containment, and both of those would 17 be analyred.
l l
18 HR. MATTSON:
The event sequences that we look at l
19 include both steps.
You are not going to look at a million i
20 such sequences.
You are going to look at what you think are 21 the dominant sequences for producing accidents that can be 22 arrested short of corenelt, and there is a finite number of 23 those.
24 CHAIRMAN HENDRIE:
But it is also an undefined 25 set.
ALCERSCN REPCRTING COMPANY ;NC,
89 1
MR. ROSS:
When you put operator action in, yes.
2 You can make it any way you want to, with some operator 3 misfeasance or nonfeasance.
l l
4 COMMISSIONER GILINSKY:
Suppose you built up an l
5 amount of hydrogen corresponding to 75 percent of the core, 6 and you now have you high point vents in, and you just open 7 up the vents.
How fast will it take for that amount of a hydrogen to get dumped into the containment?
9 MR. ROSS:
Let me answer that question.
We think 10 that it is about a half-hour.
Because we have asked this 11 question before, and people are sizing those vents very 12 small.
I don't know the exact answer, but it is less than 13 an inch in diameter.
to If you opened the PORV, and you had a system 15 half-full of hydrogen, you could get it out very fast.
I 16 think probably in a iery few minutes.
17 COMMISSIONER GILINSKY I guess this is where I 18 thought you were headed, we are going to have to put some 19 lower bound on those releases.
20 CHAIRMAN HENDRIE:
Yes, if you manage to find some 21 sequence in which you either find alive in a region in the 22 primary, and then find a way to dump a lot of it in a short 23 time, or if you find a sequence wnich has a splendidly rapid 24 evolution and release, you are going to go detonable in some 25 regions.
ALDERSCN REPCRTING COMPANY. INC,
90 1
Hy own guess on that situation is that that is a 2 sufficiently unlikely event, that is, it constitutes a 3 sufficiently small fraction of the universe of all possible 4 hydrogen evolving accident that I am willing to write it off 1
5 and say, never mind about that, at least for the purposes of 6 this in~teria hydrogen control coverage that I think we 7 need.
8 I as trying to foresee if had a plant what it is 9 that I would do in response to the words here, in order to 10 conform to the regulations of the Commission.
I must sa'y, 11 it is a highly ill-defined situation.
I am not sure what I 12 would do.
I guess I would try to get the transcript of this 13 mee ting and I see if I can figure out what the hell those 14 people meant when they talked about these analyses.
15 There is no flavor in the words that I read in the i
16 rule, even in the suppleantary considerations, or the rule 17 language itself, that says, look fellows, what we are scing 18 to do is a set of WASH-1400 type acciden~t scenario 19 calculations, and we will look at the ones that involve 20 hydrogen and try to select a group out of the set of i
21 sce na rio s tha t represents the great bulk of hydrogen 22 evolving scenarios.
l 23 Then I am going to design my protection system, l
24 ignitors or post-sccident inerting, to deal with the 25 envelope of hydrogen evolution conditions defined from that 1
ALCERSCN REPCRTING COMPANY, INC,
~... _.. _.
r 91 1 set of analyses.
2
'Jhat it appears to be, gentlemen, is that if you 3 are going to have 70 plants operating, and 30 plants 4 building, all doing 150 sets of such analyses, that is a bit 5 auch, I guess.
It ought to be done vendor by vendor on a 6 sort of bulk basis.
Furthermore, I have to scratch my head 7 a little bi t and ask for the purposes of the kind of t
i 8 coverage that I as looking for, does it rea lly have to be 9 that f an cy.
10 Do we know enough, for instance, to say, go evolve 11 hydrogen into containment at a unif orm rate which puts in 75 12 percent in one hour.
Can you stomach that; that is the 13 system we want -- or within two hours, or 45 minutes, or 14 whatever.
15 XR. NATTSON:
A sli;ht change in that would be to 16 specify specific events sequences like the old design basis 17 accident approach from Chapter 15.
18 MR. BOSS:
I just asked Bob 3ernero if he thought 19 ve were far enougn along to specify a half a doren of the 20 leading villains, and he said --
21 (General laughter.)
22
- 52. BERNE30:
Basically, with the risk assessment, 23 that is the reactor study follow up, we have one each of the 24 principal -lasses of reactors, and in each one it would not 25 be unreasonable to select f ive, six.
I don't know what the ALOEASCN AEPCRTING COMP ANY. :NC,
92 1 number would be, but it would be a measurable number of 2 sequences that are candidates to cover the spectrum of 3 hydrogen producing accidents, substantial hydrogen 4 scenarios, and bound the analysis that way.
To say, these 5-are the things that need to be addressed for a Westinghouse 6 plant.
These are the things for a GE, and so forth.
7 Two of those studies are in hard cover now, and 8 two of them are in the final stage.
9- -
CHAIRMAN HENDRIl.
When you say, it would be 10 practical to select, do you mean practical for us and our 11 contractors to do it, or are, going to each licensee to do 12 it, or let them group themselves up by plan t class as they 13 would like to do it?
14 MR. BERNERO:
I would say that we would be in a i
15 position to select for a BCW plant, a CE plant, a 16 Westinchouse Plant, and a GE plant what we believe is a l
17 reasonable spectrum of accidents for them to handle.
18 Obviously, if they make cogent comments on them, and say, 19 here is a reason why we should leave one out, and they add a
- 20. dif f eren t one.
l 21 MR. MAIISON:
Could you go the next step, and I
22 having done those analyses yourself, specif y a hydrogen l
l 23 release rate over a certain period of time equalling 75 24 percent that would be reasonable assurance, so that the 25 analysis could be foregone, the sort of thing that Denny was l
ALDERSoN REPoATING CCMPANY,INC.
93 1 just suggesting?
2 ER. BERNER0s This "Go Show Me a Rock" analysis.
3 You might very well be able to do that, if we took the 4 contractor, really sat down, sorted those analyses out 5 ourselves, and come up with a criterion tha t the release of 6 a given amount of hydrogen in a given period of time, and 7 specify the location also that would be credible.
8 ER. MATTSON:
It would be possible to get that 9 from the industry during the comment period on the proposed to rule, too.
11 COMMISSIONER GILINSKYs We would have to convince 12 ourselves that slow or moderate releases, or that releases 13 of moderate rate are, in fact, more likely than quick 14 releases.
15 C05MISSIONER AHEARNE:
Of course, going through 16 tha t scenario analysis, you might end up with a different 17 number than 75.
18 MR. ROSS:
You see, the loss of off-site power is 19 a key factor, and it has a factor of 10 and is so spread 20 around the country.
So what is good f or one, may not be 21 good for the other, although that can be quick, I think, put 22 in.
23 3RC canno t calculate with the tools it has, or 24 doesn't have available, the hydrogen distribution within the 25 building.
We cannot do that.
A1.::ERSCN AEPCRTING CCMPANY,INC,
e 94 1
CHAIRMAN HENDRIE:
I will tell you what, fellows, 2 you have worn me out.
3 The prospects are -- When were we looking 4
CORRISSIONER AHEARNE:
Tuesday.
5 CHAIRMAN HENDRIE:
People have a different dream 6 than I do; right?
7 ER. EISENHUT Are you talking about 07377 8
CHAIRMAN HENDRIE:
Yes.
That is right, I agreed 9 to do that.
We vill visit this subject again on Tuesday.
I to think at 12:30, it is high time for me to bang the gavel and 11 say, enough.
I don 't ha.>e a direction that I am anxious to 12 go here.
13 I must say, the spirit in which ! have come at 14 this interin rule, and I have asked you to please send up a 15 rule with this stuff in it, is a feeling that we ought to 16 implement a hydrogen control on these plants.
We have this 17 thing over here on Sequoyah, and we thought that if it was 18 good enough for Sequoyah, why, good, maybe that settles it l
19 for the interim.
20 Hy version of a hydrogen control rule for the 21 other ice condensers is inclined to be, not to go out there i
22 and start doing massive amounts of analysis from which one i
23 would shake down sets of scenarios, and define further sets 24 of conditions that carry on till the end of the work.
t 25 Ey idea was a rule that said, for you other ice l
ALCER$oN REPCRTING COMPANY, NC, thR K6FC 6Vik 693@hQ
95 1 condensers, go buy a set of glow plugs, and put 32 of them 2 in your containment at about the same place they put then in 3 Sequoyah.
We have looked at it enough to declare that that 4 is adequate protection for hydrogen control in ice l
5 condensers, until we can get lurther into the subject down l
6 the line in other proceedings that we contemplate.
7 You can tell me that that is not practical.
Maybe 8 the Commission would not want to go more toward tha t line.
9 We have got here one whale of a industry-wide political 10 effort, and I can see us all in 18 months agreeing that we 11 will have to have another year to digest the analyses t, hat 12 have now been submitted, and are completely filling one of 13 the rooms in the basement of the Phillips Building, a6d 14 there really isn't anybody to start reading them all.
15 Gee, maybe safety would have been better served if 16 those guys had just gone and put in some glow plugs.
17 So let us talk about this some more on Tuesday.
18 Anybody who has got any ideas, or who generates any ideas in l
l 19 the meantime, we will be glad to hear them at that time.
20 (Whereupon, at 12:40 p.m., the Commmission l
21 adj o urne d. )
22 l
23 24 25 ALOERSCN AEPCRT1NG COMPANY, INC,
e tiUCLEAR REGULATORY CO!"MISSICN
-a,
...a.,
. u. g... u..
... u
- u.,.r.,. u.,.
2..,c..a.,
........sa in the latter Of:
Commission ' eeting (10.10)
Date c f.:r0c eecing :
April 23, 1981 Decket Nuc'Oer:
. ac. -.
.m.
c..,4 Washington, D.
C.
a
.--..s.
- e.-.
- u. g s.
,3
- u.. n. '..
a.. ears,.= r. - ~.. ^.. =.
~. '. =.. ' s '...=.'
~ ~ =- = ~~
. u.... o.
.--.u..
4.-. e.r
.w.
.-..4.4..
.w-.
I I
l Patricia A.
Minson c..c 4. 4 :: :...., I. 2., e...., 3, e6
.,.e w 4. J,a..
WWJ
...-,.4,-
..w.--
- ..=.....
s....-...
t I
l l
l i
-.. ~,, -.,. _ _ - -, - - -
c
.-,-e
--r
,1~.~-,w
---~~*~r
~- - ' ' - - ~ - -
m
- --