ML19257B492
| ML19257B492 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 01/02/1980 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML19257B493 | List: |
| References | |
| REF-10CFR9.7 NUDOCS 8001160420 | |
| Download: ML19257B492 (27) | |
Text
s NUCLEAR REGULATO tY COMMISSION
?-
a IN THE MATTER OF:
PUBLIC MEETING BRIEFING BY NRR ON ORDER IN POINT BEACH STEAM GENERATOR TUBE DEGRADATION l'
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g.
7 Place -Washington, D. C.
Date. Wednesday,. 2 January 1980 Pages 1-23
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1753 110 r--
(cede 202) 547-6222 ACE - FEDERAL REPORTERS, INC.
s-Official Reporters os wa w. N.e.
L7 i..
%shington, D. C. 20002 8001160 j NATICNWIDE COVEUG2
- R9052 1
DISCLAIMER This is an unofficial transcript of a meeting of the United States Nuclear Regulatory Commission held onWednesday, 2 January 1980 in the Commissions's offices at 1717 H Street, N. W., Washington, D. C.
The This transcript meeting was open to public at'tendance and observation.
has not been reviewed, corrected, or edited, and it may contain
' inaccuracies.
The transcript is intended solely for general informational purposes.
As provided by 10 CFR 9.103, it is not part of the formal or informal record of decision of the matters discussed.
Expressions of opinion in this transcript do not necessarily reflect final determinations or beliefs.
No pleading or other paper may be filed with the Comrission in any proceeding as the result of or addressed to any statement or argument contained herein, except as the Commission may authorize.
I753 111
CR9052 2
SAV:fr UNITED STATES OF AMERICA j
2 NUCLEAR REGULATORY COMMISSION 3i PUBLIC MEETING 4
BRIEFING BY NRR ON ORDER IN POINT BEACH 5
STEAM GENERATOR TUBE DEGRADATION Room 1130 7
1717 H Street, N. W.
8 Washington, D.
C.
9 Wednesday, 2 January 1980 10 The Commission met, pursuant to notice, at 11:30 a.m.
11 BEFORE:
12 JOHN F. AHEARNE, Chairman 13 RICHARD T.
KENNEDY, Commissioner ja JOSEPH M.
HENDRIE, Commissioner 15 PRESENT:
16 Messrs. Eisenhut, Noonan, Shapar, Gossick, Trammell, Bickwit, j7 Denton, and Hanrahan.
18 l
l 19 20,
21 22 j
23 24 l
. Federal Remxws. im.
}
25 1753 112 I
I
CR 9052 3
HOFFMAN t-1 mte 1 I
CHAIRMAN AHEARNE:
Before we get started, the 2
Commission first must vote to hold a briefing on an order on 3
Point Beach, vote to hold on less than one week's notice.
(A chorus of ayes.)
5!
CHAIRMAN AHEARNE:
Lee, before I turn to you to get 6
started, I have asked the general counsel to briefly review, 7
for my benefit and perhaps the other Comissioners' benefits, 8
if there are any ground rules on this morning's discussion.
9 MR. BICKWIT:
The ground rules stem from the fact 10 that an order is out at this point and a hearing has been 11 requested on that order.
Under the language of 2.780, the 12 ex parte bar is thereby triggered.
The line of cases, however, I
to the effect that the Commission must be able to continue l#
to perform its investigatory functions or the functions asso-15 ciated with it, and because of that line of cases it is possi-16 ble for staff to communicate with the Commission in order for i
I7 l the Commission to perform those functions.
18 In the case of this briefing, what the Commission 19 is being briefed on is what action to take with respect to 20 the issuance of an order involving pressure levels, as I 21 l understand it.
So long as the discussion remains on that 1
matter and any matter relevant thereto, even if in order to 23 be relevant thereto you must seep over into discussion of 24 matters which are before the Commission in ad-judication, that Federra Reporters. Inc.
25 discussion may take place.
}
f
mte 2 4
1 As a matter of discretion, I would suggest that the 2
Commission make available to other parties to the proceeding 3
that is now in progress a copy of the transcript of this 4
meeting and allow them to respond to any representations made 5
by the staff in this briefing prior to any Commission action 6
in the adjudication.
7 CHAIRMAN AHEARNE:
Joe, do you see any problems?
8 COMMISSIONER HENDRIE:
No.
9 CHAIRMAN AHEARNE:
Fine.
Let's then make sure we 10 do that.
And I assume that you will leap in verbally if there 11 is a point where you believe things are going beyond the line 12 which you believe ought to be drawn.
13 MR. BICKWIT:
Yes.
14 CHAIRMAN AHEARNE:
Shielded, then, by the general 15 counsel, Lee?
16 MR. GOSSICK:
Mr. Denton will introduce the 17 discussion.
18 MR. DENTON:
We last met with you on November 28th, I
19 and I won't go into that any more than to say that what we'd I
20 like to cover today is some new information that's been 21 available since the last order was issued, and also discuss 22 with you an additional order that we've proposed about 23 primary system pressure and an attempt to operate within the 1
24 guidelines.
Federal Reporters, Inc.
25 Mr. Trammell is the project manager who will address it i753 114 I
i
Ete 3' 5
1 MR. TRAMMELL:
When we had that prior discussion on 2
Point Beach on November 28th, there was one item for which 3
in the licensee's corrective in his program, that he wanted 4
to do, which required an amendment to his license.
That was 5
his proposal to reduce pressure to 2,000 psia from his cur-6 rently licensed pressure of 2250 psia.
At the time that we 7
had our discussion on November 28th, we had not completed our 8
review of this aspect of it.
9 It was an item that required a little digging, 10 because it went back some years in time to when the licensee 11 had done it before, and the information that was furnished 12 was basically -- appears before you in the references, and we 13 wanted to do it again.
It took a little time to dig through 14 the references.
15 We have finished our review now of his proposal to 16 reduce primary system pressure.
We find it an acceptable 17 proposal.
Basically, the history of it is that pressure was 18 reduced in 1975 or thereabouts as a result of the fuel l
19 densification problem; and it was raised again some years after 20 that because of a different fuel problem.
i 21 COMMISSIONER KENNEDY:
Could you tell us what year?
{
22 MR. TRAMMELL:
That year was -- just a second.
23 (Pause.)
24 It was issued as an amendment to the license on l
dFederal Reporters, Inc.
25 May 23rd, 1974.
I753 115 I
nte 4 6
1 CDMMISSIONER KENNEDY:
As an amendment?
2 MR. TRAMMELL:
As an amendment.
3 COMMISSIONER KENNEDY:
1974?
4 MR. TRAMMELL:
May 23rd, 1974.
That was for Unit 1.
5 The same amendment or the same action was taken on Unit 2 on 6
September 30, 1974.
7 CHAIRMAN AHEARNE:
What was the total coverage of 8
the amenmdent?
9 MR. TRAMMELL:
Reducing primary system pressure.
10 CHAIRMAN AHEARNE:
That was the only thing?
11 MR. TRAMMELL:
Yes, sir.
12 Now, the main aspect of doing something like that, 13 when the licensee then requested to raise his primary system 14 pressure back to 2250 about two years later -- I don't have 15 that date -- in effect, he did not take credit in his protec-16 tive equations for the increased margin that he would derive 17 from raising the pressure margin with respect to boiling 18 transfer.
19 So, now that he's requesting permission to reduce 20,
pressure back to 2,000, essentially his margins with respect i
21 !
to departure from nuclear boiling are what they were in l
22 previous years.
So it's not a significant change.
23 CHAIRMAN AHEARNE:
You're saying that the calculations 24 that were used to support the licensing after that amendment Federe' Reporters, Inc.
25 were then done on the basis of 2,000?
1753 116
ute 5 7
1 MR. TRAMMELL:
Yes, that's right.
2 COMMISSIONER AHEARNE:
And were never changed.
3 MR. TRAMMELL:
He could have taken extra credit for 4
this and have the recent operating margin.
But this was never 5
requested.
So essentially back today where we were previously, 6
2,000 pounds per square inch.
7 COMMISSIONER KENNEDY:
You say there is not a sig-8 nificant change in the margin of safety?
9 MR. TRAMMELL:
There's not a significant change in 10 the margin of safety, that's correct, from the licensing 11 standpoint.
It's obvious, though, that when you go from 2250 i
12 !
down to 2,000, in fact, there is a change in margin.
But with 13 respect to this license margin, there has been very minor 14 change.
15 COMMISSIONER KENNEDY:
What is the actual difference?
16 MR. TPAMMELL:
I'd have to ask somebody else.
We 17 did run some numbers on that to see.
18 COMMISSIONER KENNEDY:
Could you tell us what the 19' numbers are?
20 MR. TRAMMELL:
Do you have any idea in what units 21 it would be meaningful?
I i
22 MR. LOBEL:
For the LOCA analysis, the peak clad 23 temperature went up 9 degrees.
The metal-water reaction 24 number was really an insignificant change.
I think it went
,s.o.r.i neponen, inc.
25 from like 5.1, 5.3 down to 5.1 percent metal-water reaction.
1753 117 i
Ete 6 8
1 In terms of subcooling, to get an idea of the margin to 2
subcooling, I suppose you could just use the fact that the 3
pressure corresponding to the saturation pressure, correspond-ing to the hot leg temperature, would be around between a
5 1500 and 1600.
I'm just guessing.
And they're operating at 6
2,000 if this order goes through.
So that gives you the 7
margin.
8 COMMISSIONER KENNEDY:
Thank you.
9 CHAIRMAN AHEARNE:
Could you explain why, since 10 they proposed this before, why you didn't incorporate it in 11 the previous order?
12 MR. TRAMMELL:
I guess the simple answer is we hadn't 13 finished our review.
Licensing gave us a letter saying 14 basically:
we would like to reduce pressure to 2,000 psia.
15 We did it before.
Here are the references.
And that required 16 digging out references back to 1974, some Westinghouse 17 technical publications.
It goes back to June
'73.
It takes 18 a little while to sort it out.
The plant has changed in that 19 period of time.
We wanted to be sure that the picture that 20 was accurate in 1974 -- there hasn't been some new problem 21 introduced in that intervening period of time that would 22 cause this to be a different problem.
23 CHAIRMAN AHEARNE:
For the purpose of the transcript, 24 will you identify yourself.
e Federal Reporters, Inc.
25 MR. LOBEL:
My name is Richard Lobel.
I'm in the 1753 118
ute 7 9
1 Division of Operating Reactors.
I'd Like to enlarge just a 2
little bit on what Charlie was saying.
Wizat they did was redo 3
their analysis in a way to maintain the same margin.
But they 4
did go back -- this is the licensee -- they did go back and 5
review all his postulated accidents and transients, and 6
recalculate those that weren' t bounded by the previous results.
7 So he went through each one in his FSAR and looked to see if 8
they were still bounded by the previous analysis.
Where they 9
weren't, he redid the analysis, and LOCA is one of the calcula-10 tions that he redid.
11 So there were new calculations to be reviewed in 12 addition to reviewing what was done in the past.
I 13 HR. DENTON:
A change in pressure is such a funda-14 mental change, it affects all your transient calculations.
15 And this requires an across-the-board look.
There are some 16 other parameters we can review.
So we looked at it to be sure 17 that it didn't introduce any strongly negative statement.
It 18 does have some positive advantages.
Maybe that's what you 19 can turn to next, Charlie.
20 MR. TRAMMELL:
The positive advantages do relate 21 to their current difficulties with the steam generators.
As i
22 you will recall, one of the proposals that they had or one of 23 the items that they wanted to do to try to alleviate the l
l 24 problem was to reduce primary temperatures that they had seen l
e Federal Reporters, Inc.
25 or they believed that a correlation existed between the 1753 119 l
ute 8 10 1
temperature of the steam generator and the rate of corrosion.
2 And so they decided they would operate the plant.
They 3
reduced the hot leg temperature down from 597 down to 557 or 4
thereabouts, because they'd seen no tube problems in the cold 5
leg, which operates a little colder than that, but it's in 6
that ballpark.
7 But in doing the reductions in primary system 8
temperature, they actually aggravated the problems associated 9
with differential pressure across the tubes, because in lower-10 ing the average temperature of the reactor, he lowered the 11 steam pressure.
At the same primary pressure, he lowers the 12 steam pressure about 200 psi.
So instead of business as 13 usual at 1400 psi differential or thereabouts, he actually 14 increased this to 1600 psi.
So the reduction in pressure is 15 really a necessary part of the package, because just taking 16 reduced temperatures by themselves, you increase the stress 17 across the tubes by about 15 percent.
I 18 CHAIRMAN AHEARNE:
So this is really an attempt to l
19 restore and go back to the previous differential pressure?
20 MR. TRAMMELL:
Yes, it just takes them back to 21 normal differential pressure.
22 MR. EISENHUT:
The licensee had requested the 23 flexibility to operate in either one of these modes.
We i
24 believe that it's important, as our memo of Monday stated, Federal R eorters, Inc.
25 that it's no longer desirable, and we think it's necessary 1753 120 1
ate 9 11 1
and prudent that that margin be restored back to the conditions 2
where in fact we have some operating experience on this plant 3
to know how it has been behaving, that is, with respect to 4
And everything I'm saying is directed 5
towards the steam generators.
This is back in the framework of 6
where at least we have now a couple of data points on steam 7
generator tube inspections that shows what has been happening.
8 CHAIRMAN AHEARNE:
Let me try, though, to make sure 9
I understand that previous point that Mr. Trammell was just 10 making.
The 2250 to 2,000 isn't so much to get a substantial 11 reduction of differential in pressure from previous operating 12 modes; it's to get back towards more the differential pressure 13 that was existing before the more recent change?
14 MR. TRAMMELL:
That's right.
It appears to be a 15 reduction -- this would help, in fact, because of the reduced 16 T-average.
What he's really doing is going back to about 17 business as usual with respect to differential pressure across 18 the tubes.
l 19 MR. EISENHUT:
In other words, we had a f amily of 20 1 parameters, the package that we discussed in late November.
I 21 We approved by confirmatory order all but one.
We couldn't l
22 approve that one at the time because the staff hadn't completed' 23 its accident analysis.
24 That basically summarizes what we were proposing e Federa? Reporters, tric, 25 saying about the primary system pressure reduction.
If 1753 121
mte 10 12 1
there's nc other questions on that, we'd like to discuss from 2
a safety significance standpoint --
3 CHAIRMAN AHEARNE:
Let me first find out whether 4
there are any questions.
5 COMMISSIONER HENDRIE:
As a matter of curiosity, 6
what's that 40-degree drop on the hot leg worth in power?
7 MR. TRAMMELL:
The licensee is operating at about 8
80 percent.
It costs him about 20 percent power, the reason 9
being that he is steam flow-limited.
I gather turbine valves 10 are just about wide-open at that point, and that's the 11 limitation.
12 MR. EISENHUT:
As of this morning I believe it was, 13 what, 76 percent?
I think we called this morning.
It was 14 76, 76-1/2 percent.
15 CHAIRMAN AHEARNE:
Any other questions?
16 (No response.)
17 COMMISSIONER HENDRIE:
It's a straightforward matter.
18 CHAIRMAN AHEARNE:
Go ahead.
19 MR. EISENHUT:
We'd like to discuss also the safety 20 significance of five additional defects that were recently 21 reported and what they mean to our evaluation and how they 22 fit into this overall package, just briefly this morning.
23 And Vince Noonan, who is the branch chief of the Engineering 24 Branch in Operating Reactors, will be discussing that.
e-Federal Reporters, Inc.
chief of the 25 MR. NOONAN:
My name is Vince Noonan,7 5312 2 1
nte 11 13 1
Engineering Branch, Division of Operating Reactors.
What we 2
did is, when we discovered the five tubes that had defects at 3
the tube sheet or slightly above the tube sheet, the engineering 4
staff took a look at this data and basically did another 5
safety-type evaluation, what we would have done in our original, 6
on November 30.
7 The basic conclusion was that the evaluation would 8
have changed the margin that we had addressed these tubes and 9
what the impact of these tubes had and what actions we might 10 take as far as further investigating the cause of this. problem.
11 The conclusions of our November 30th SCR would not have changed.
12 We do not feel that this is a new safety problem.
We think 13 the problem has basically been one of the problem that's iden-14 tified in the '72 '75 era, when you had thinning and cracking.
15 In our presentation we showed on one of the viewgraphs -- in 16 November 28th, we showed in that area, before you made the 17 conversion to ABT, they had substantial numbers of thinning 18 and cracking tubes.
19 It's the licensee's contention that these five 20 tubes have always been there, they did recognize them back 21 in that era; they never were reportable because they were never 22 identified as more than 20 percent loss of wall.
They weren't 23 reportable.
24 COMMISSIONER KENNEDY:
Excuse me, Vince.
You're e Federal Reporters, tric.
25 saying that the licensee is saying that those five tubes in 1753 123 i
mte 12 14 1
fact are not new problems.
2 MR. NOONAN:
That's right, sir.
3 COMMISSIONER KENNEDY:
They have been problems ever 4
since the '72 '75 time frame.
5 MR. NOONAN:
That's right.
Their indication is that 6
they were never serious enough to cause the tube to fail.
7 The October outage had all known defects.
These 8
five tubes were then bought.
9 CHAIRMAN AHEARNE:
When was the previous time that 10 those tubes would have been measured?
11 MR. NOONAN:
The earliest date that I know of that 12 they show any indication is in 1975, 13 CHAIRMAN AHEARNE:
No.
What was the latest before 14 October?
15 MR. NOONAN:
They were noted, evidently, in all 16 inspections after that time.
17 CHAIRMAN AHEARNE:
I'm not so much concerned about 18 the noting.
What's concerning me is that in this, when it's 19 described as a percentage defect, what does that mean?
Does 20 that mean how much the wall has been thinned?
21 l MR. NOONAN:
How much the wall has been thinned, 22 right.
23 CHAIRMAN AHEARNE:
One of these is an 80 percent 24 defect.
e Federal Reoorters, Inc.
753 124 25 MR. NOONAN:
Yes, sir.
ate 13 15 1
CHAIRMAN AHEARNE:
Which is greater than the 2
20 percent.
So I'm really wondering when it goes back to.
3 MR. NOONAN:
In the October inspection, these tubes 4
.ere inspected using new techniques that I think we discussed 5
before.
Number one, they had a multi-frequency type of 6
program.
In addition, they did one other thing.
On the 7
trip that we took up to Point Beach on December 16th, myself 8
and Mr. Swencer and FT. Herman from my staff, they explained 9
to us that they did actuall two things.
One was this new 10 probe.
Secondly, they had moved all the instrumentation 11 outside and they had put a preamplifier on the system.
This 12 amplifier helped them enlarge the signal and get better 13 discrimination on the signal.
It's a definite improvement 14 over the old system.
15 These tubes now could be better defined.
And using 16 these techniques instead of, as reported, using the old 17 technique, when he said he had less than 20 percent wall e-1 18 thinning, the numbers now appear to be much greater.
19 20 21 l
22 23 24 1753 123 Federal Reporters, Inc.
25 I
)52 02 01 16 mgcDAV I
CHAIRMAN AHEARNE:
Are you saying that the 2
equipment change led them to shift from a number of le ss 3
than 20 percent to 30 percent?
4 Md. N00NAda Yes, sir.
5 CHAIRMAN AHEARNE:
Did they redo all the tubes 6
with the new equipment?
7 MR. NOONAN:
100 percent inspection was done in 8
the October inspection.
9 CHAIRMAN AHEARNE:
30 that as far as the 10 measurements of the new equipment are concenrned, other than 11 the previously reported tubes, these are the only five in 12 addition that showed greater than 20 percent?
13 MR. NOONAds Yes, sir.
Since they had the other 14 leakage in December, you came down and did another 1900 tube 15 inspections, both 950 in each generator, which was not 16 required by the staf f but which was done strictly at their 17 own initiative, and they did look at the tube sheet area.
13 In fact they looked above the tube sheet.
I don't know the 19 exact numoer, but significantly above the tube sheet.
They 20 reported no defects whatsoever.
21 The new criteria now on plugging is zero def ects.
22 CHAIRMAN AHEARNE:
Now, what is your basis.
Does 23 the staff agree with the licensee's claim that this is a 24 72-75 problem?
25 MR. NOONAd:
To the best of our knowledge at this 1753 126
>5'2 02'02 17 mgcDAV I
point in time, we have no reason to doubt that --
2 CHAIRMAN AHEARNE:
Could you explain why?
3 MR. N00tl Ad
- Because, as reported by the licensee, 4
they saw no significant change in these single frequency 5
indications.
There was no change at all from the 1975 6
period, we think, at least on one tube, very definitely they 7
would have noticed the change with the single frequency 8
probe, because once you get down to that interf ace there, 9
the single frequency is a pretty good measurement of wall 10 thinning.
.II COMMISSIONER KENNEDY:
You're sa ying the eddy 12 current probe would not necessarily have revealed an 13 increase in blockage between 20 percent and 80 percent?
14 MR. NOONAN:
I'm saying with the single frequency, 15 they did not notice any change in the signal whatsoever 16 since 1975.
While there's some question, not only amongst 17 the staf f but among other people as to the e ffectiveness of 13 single frequency eddy current testing right at the surface, 19 the one tube that they reported that's a half inch above the 20 surf ace of the tube sheet would definitely have been within 21 the capabilities of the single frequency probe.
That did 22 not show any changes.
23 CHAIRMAN AHEARNE:
You're saying that over the 24 last four years or so, they have identified that tube has 25 having sone thinning, but they have never gotten it above the 1753 127
18
>52 02 03 mgcDAV 1
the 20 percent?
2 MR. N00NAJ That's right, sir.
3 MR. DENT 0d Let me try to say it another, Vince.
4 All indications are that these five were relating to that 5
previous wastage problem and are not a part of other 6
granular corrosion that's rapidly a ff ecting tubes.
7 CHAIRMAN AHEARNE:
Now on a physical examination 8
of that tube, you ought to be able to tell the difference, 9
shouldn't you?
10 MR. fl00tlAd Yes, sir.
11 CHAIRMAff AHEARNE:
Do you intend some time in the 12 f uture to have physical examination of the tubes?
13 M R. fl 0 0 tl A N :
Sir, we're going to be discussing 14 that with the licensee.
In fact, we have met already on the 15 night of the 21st.
We had a preliminary talk with 16 Mr. Bernstein and talked about making these types of 17 insp ec t io ns.
18 CHAIRMAN AHEARNE:
I'm not sure I understand.
Are 19 you saying you're going to be discussing whether or 20 discussing when?
21 MR. fl00 NAN:
I think we'll be discussing how many.
22 (LaJghter.)
23 CHAIRMAN AHEARNE:
As long as it's not zero.
24 MR. EISENHUT I think it's our position that we'd 25 like to see some of the tubes removed for examination.
When 1753 128
19
)S20204 mgcDAV i
and how many is the real issue that we're discussing right 2
now.
3 I think that the answer to when, unless there's a 4
strong justification not to, is 7oing to be at the end of 5
the 60 day eff ective f ull power outage.
6 CHAIRMAN AHE ARNE:
But ca-you assure us that at 7
least some of these particular tubes will be examined.
3 MR. DENTON:
I think -- I had not planned to try 9
to cover tha t in the scope of the order we're discuss ing 10 today, but if it turns out that we're unable to resolve to 11 the staff's satisfaction, va'll be back with further 12 inf o rma t io n.
13 MR. dISENHUT I think that summarizes the two 14 are as we wanted to address today -- both the five tuces and 15 the conf irma tory order.
16 MR. DENTON:
One other point.
I understand that 17 the language of the order has been resolved to the 16 satisf action of both OGC --
IV CHAIR:4AN AHEARNE:
dell, cefore you get to that, 20 can I ask a question.
Can you say a few words about the 21 last session we had?
One of the significant issues which 22 was raised, and then the staf f indicated the resolution of 23 it, or answer the question of where those cracks might be, 24 and in fact, if the cracks occurred in the crevices, that 25 that would constrain the loss rate.
1753 129
~
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.mgcDAV I
Now here you have five cracks which are not in the 2
crevices.
Can you make any comments about whether that 3
adjusts your conclusion as far as the safety sign'.icance of 4
the situation?
5 MR. DENfoll:
It would change the probability, in 6
that cracks above the tube sheet obviously are not 7
physically restrained as ones that are in the tube sheet, 8
and the purpose of the wastage criteria are to assure that 9
tubes didn't grow between inspections to the failure point.
10 So with the inspection schedule, you can find 11 cracks that were above the tube sheet and have adequate time 12 to plug them so they wouldn't f a il.
I the cracks, these 13 five, are due to these other phenomena, that would change 14 the probability of steam generator tube rupture.
15 So obviously the intent of the specification is to 16 prohibit operation that would get you into f ailures on those 17 tubes above the tube sheets.
18 CHAIRMAN AHEARffE:
But my question, I think, is 19 that last time one of the issues was whether the plant 20 should be allowed to continue to operate based on this, and 21 the argument presented was that because of the cracks in the 22 crevices, that there was not a significant danger of 23 allowing the plant to continue operating.
24 We now have five cracks that are not in the 25 crevices.
Does that adjust your conclusion as f ar as the 1753 130
152 02'06 21 mgcDAV I
recommendation as to whether or not the plant should be 2
allowed to continue to operate.
3 MR. DENTON:
No, i t do esn't, because it's our view 4
that these five cracks were old cracks related to problems 5
that had occurred in the past.
And it's not an ongoing 6
problem above the tube sheet.
.Ne have very tight 7
specifications on this plant.
3 If between now and the 60 days we find out that 9
cracking is really occurring above the tube sh'eet, it would 10 change our views, but as the moment we see these five as not 11 changing our previous views on the cracking problem in the 12 tube sheet itself.
13 MR. NOONAN:
If I could, sir, please, I'd just 14 like to slightly co rrect the record.
Right now the five 15 tubes have been reported as defects.
To the best of our 16 knowledge, we do not know that these are cracks.
17 CHAIRMAN AHEARNE:
Right.
Thin wa lls.
18 MR. N00 Nail:
Wall thinning.
They're reported in 19 the chart as thinning or cracking.
We are not sure at this 20 point in time.
We do note that they're recorded as defects, 21 not as cracks.
22 I'd also like to point out that since that time 23 now, we have done two tests -- a static hydrotest on the 24 primary side of 200J psi and 800 psi on the secondary side, 25 both in October, and in the latest outage, and there are --
1753 131
152 0 07 22 mgcDAV i
MR. EISENHUT The other piece to go with that is 2
we think the rate of degradation, based on history in the 3
past -- the rate of degradation is suf ficiently slow so as 4
not to be a concern during this period of the rest of the 5
60 effective full power days.
6 CHAIRMAN AHEARHE:
Bef ore the Ge neral Counsel 7
talks, Joe, do you have any further comments?
3 COMMISSIONER HENDRIE No.
I don't have any 9
problem with it.
The tube sheet steam generator tube 10 cracks, and once in awhile ruptures have occurred.
They 11 certainly are a burden on the plant operator to take care of 12 them, but in the context of reactor safety in the broad 13 sense, I don't f ind it a ma jor problem.
The sta ff aopears 14 to me to have it well in hand.
~
15 MR. BICKWIT:
I just was about to say that we 16 can't say we're in agreement with the language because we 17 haven't yet seen the language, but judging from cur 13 discussions on the phone, I suspect that once we see it we 19 will be in agreement.
20 MR. DENTON:
I guess I said that orally.
My 21 understanding is that we're writing the order to conform to 22 the telephone conversation.
23 MR. BICKWIT:
I think 4e'11 be okay.
24 MR. SHAPAR I'm not sure, but I hope so.
25 MR. BICKdIT:
I'm ne ve r sure.
1753 132
152 02 08 23 mgcDAV i
(Laughter.)
2 COMMISSIONER KENNEDY:
Even af ter they're issued.
3 CHAIRM AN AHEARNE:
So I guess, would it be correct 4
to say that assuming the General Counsel does not find any 5
dif ficulties, we are in agreement?
6 COMMISSIONER HENDRIE:
True.
7 CHAIRMAN AHEARNE:
All right.
Anything else?
8 MR. DENTON:
No.
That's it.
9 CHAIRMAN AHEARNE:
Thank you.
10 (Whereupon, at 12:05 p.m.,
the hearing was 11 adjourned.)
12 13 14
~
15 16 (Q
17 la 19 20 21 22 23 24 25 1753 133