ML20199A507

Summary of 971211 Meeting W/Comed in Rockville,Maryland Re Additional Justification for Proposed Methodology for Estimating voltage-dependent Growth Rates of Outer Diameter Stress Corrosion Crack Indications Left in Service

ML20199A507
Person / Time
Site:	Braidwood
Issue date:	01/16/1998
From:	Lynch D NRC (Affiliation Not Assigned)
To:	NRC (Affiliation Not Assigned)
References
NUDOCS 9801270234
Download: ML20199A507 (37)

Text

-- -. --- - - ~ _ - . - - . - - . - - - .- - _ _. _ _ _-

a ne M- M j j- \ UNIYED 8TATES 1- NUCLEAR REGULATORY COMMISSION

• I WAsHINeTott, D.C. asses.4eet  :

January 16, 1998 4

d

. LICENSEE: Commonwealth Edison Company (Comed)

FACILITY: BRAIDWL ~ATION, UNIT 1

SUMMARY

OF DECEMBER 11,1997, MEETING ON COMED'S ADDITIONAL JUSTIFICATION FOR ITS PROPOSED VOLTAGE DEPENDENT METHODOLOGY REGARDING THE GROWTH OF ODSCC FLAW INotCATIONS LEFT IN SERVIOE

- On December 11,1997, the NRC staff met with representatives of Comed in Rockville, Maryland to discuss ComE(s additional justification for its proposed methodology for estimating the voltage-dep, lent growth rates of outer diameter stress corrosion crack (ODSCC) indications

_ left in service. A list of the attendees is proAded in Enclosure 1. A copy of tne licensee's presentation is provided in Enclosure 2.

The licensee had boon authorized to implement a 3.0 volt interim plugging criteria (IPC) for Beeldwood, Unit 1, in the license amendment issued on November 9,1995. Subsequently, lo the eddy current inspection (ECl) conducted in the spring 1997 refueling outage, the as found  ;

i OD8CC indications in the h6gher voltage range (i e., the tail of the distribution) at the end of cycle l_

(EOC) 6 were higher than those predicted in November 1995, at the start of Cycle 6. At a meeting with the staff on July 23,1997, Comed proposed a methodology using voltsge

, dependent growth rates to reconcile the observed EOC 6 voltage distributions in the upper l voltage range with predicted EOC4 distributions. (Refer to the Meeting Summary issued on August 25,1997.) While ComEss proposed methodology addressed the unconservative nature of the EOC4 voltage distribution predicted in November 1995, the staff noted that there was a significant problem arising from the proposed use of voltage dependent growth rates. Namely, the proposed methodology introduced additional compier.ity into the prediction of EOC voltage l

distributions which was based on a limited data set from only one cycle of operation at one unit.

While the staff believed the methodology proposed in the meeting of July 23,1997, appeared to be a reasonable approach, N further stated that further benchmarking weuld t>e necessary to validate the use of voltage-dependent growth rates, f

Subsequently, the staff issued a request for additional information (RAI) on October 7,1997, in which Comed was asked to determine the sensit!vity of the predicted EOC steam generator (SG) ,

tube leakage to the binning strategy used in the analysis of voltage-dependent growth rates, Comed responded to this RAI in hs letter dated October 15,1997. The staff subsequently stated h/

its conclusion in its letter dated November 13,1997, that Comed had not provided sufHelent justification in its response of October 15,1997, for acceptance of its revision to its proposed ,

methodology nor for any of the attemative approaches contained in this letter, 4 Comed requested the subject meeting on December 11,1997, so as to provide the staff with a(ditionaljustification for its latest revision to Ns proposed voltage dependent growth rates. At

' this meeting, Comed stated that its analysis of about 24,000 data points, almost all from steam generators in foreign nuclear power plants similar to Braidwood, Unit 1, led it to conclude that the EOC vohage growth, and therefore, voltage distribution is both predictable and bounded. Using this large body of data, it believes that h can provide appropriate justification for a conservative .

bowling EOC leak rate of about 122 gallons per minute (gpm). On this basis, it has performed 9901270234 990116 PDR ADOCK 05000456

> P .PDR _

r. i t.

\

Meeting Summary 2-another operability assessment and administratively reduced its dose equivalent lodine 131 (DEI) primary coolant concentraiion limit to 0.05 microcuries per gram from its previous administratively controlled limit of 0.10 microcuries per gram; the present technical specification (TS) limit is 0.35 microcuries per gram. Comed stated that it would submit a technical report on this issue by January 15,1998, together with a revised license amendment request to lower the value of the present TS limit from 0.35 to 0.05 microcuries per gram.

At the condusion of this meeting, the staff complimented Comed on its effort to obtain and analyze the data from foreign operating nuclear plants, thereby significantly providing enhanced justification for its proposed revision to its treatment of voltage-dependent Ol> SCC growth rates.

The staff also indicated that it did not at that time find any impediment to conductir.g an expeditious review of the forthcoming technical report.

V fM a M. David Lynch, Senior Project Manager Project Directorate 111-2 Division of Reactor Projects - lil/IV office of Nuclear Reactor Regulation Docket No. STN 50 456

Enclosure:

1. List of Meeting Attendees

2. Licensee's Presentation cc tv/encis: See next page

-.__.__.____-.________..m._ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

-r-

p: a ', e Meetmg Summary 2 January 16. 1998 another operatsty assessment and administratively reduced its dose equivalent lorfine -131 ~ -1 i

- (DEI) primary coolant concentration limit to 0.05 microcunes per gram from its previous administratively controlled limit of 0.10 microcuries por gram; the present technical tpecircation

' (TS) limit is 0.35 microcuries per gram. Comed stated that it would submit a technical report on this issue by January 15,1998, together with a revised license amendment request to lower the -

value of the present TS limit from 0.35 to 0.05 microcuries per gram.

At the conclusion of this meeting, the staff complimented Comed on its effort to obtain and -

analyze the data from foreign operating nuclear plants, thereby significantly providing enhanced justification for its proposed revision to its treatment of voltage-dependent ODSCC growth rates.

The staff also ind6cated that it did not at that time find any impediment to conducti ig an .

L expeditious review of the forthcoming technical report, j

^

Orig signed by ,

M.- David Lynch, Senior Project Manager Project Directorate ill 2 Division of Reactor Projects - Ill/lV Office of Nuclear Reactor Regulation Docket No. STN 50-456

~

Enclosure:

1. List of Meeting Attendees

2. Licensee's Presentation i oc w/encis: See next page <

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Post Dfiloo Bos 365, Bay 234 W. en, Lewis and Bochius Pemburgh,Pennsylvanie 15230 18 M Street. N.W. i

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Gallo & Ross lilinois Department of Nuclear Safety  ;

Office of Nuclear Facilty Safety 1250 Eye St. N.W., Suite 302 4 Washington, DC 20006 1035 Outer Park Detve Sprin0Aeld, Illinois 62704 ReplonelMminletrator U.S. NRC, Region 111 Commonwealth Edison Company l- 801 Warrenvllie Road - Breldwood Station Mona0er Linie, Illinois 80632-4351 RR 1 Box 84 traceville, Illinois 90407  ?

i Ms. Bridget uttle Rotem i Appleseed Coordinator Document Control Dook-Uooneing 1 117 N. Unden Street Commonwealth Edison Company ,

Essex, Illinois 60936 1400 Opus Place, Suite 400 i Downers Orove, Illinois 60615 Howard A. Learner n EnvironmentalLow and Policy Commonwealth Edison Company .

, Center of the Mldweet Site Vice Proeident. Breldwood

!- 203 N. Letelle Street RR 1, Box 64 Sulle 1390 Braceville,IL 80407 Chice00, Illinois 00601 t Mr. Michael J. Wallace l U.S. Nuclear Regulatory Comminaion Nuclear Services Senior Vlos F.seident Braidwood Roddena inspectors Office Commonwealth Edison Company Rural Route #1, Box 79 Exeeveve Towers West til ,

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Brecoville, Illinois 60407 1400 Opus Place, Suite 900 Downers Orovo,IL 00615 l

Mr. Ron Stephens

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Chelrmen - -- Downers Grove,IL 80615 Wls County soord of Supervisors WillCounty Board Courthouse Mr. Steve Perry .

Jollet,INinoin 40434 SWR's Vice Proeident Commonwealth Edison company ,

Ms.Lorraine Creek - Execupve Towers West til

RR 1 Box 182 - - 1400 Opus Place, Suite 900 Mentono, Illinois 00950 Downers Orove,IL 60515 I

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Ms. trene Johnson,i.loonsing Director i Nuclear Regulatory Servloes i Commonweellh Edloon Company Esecuevo Towers West M .

1400 Opus Pleos Sune 500 Downers Orcwo,ll. 00515 Commonweellh Edison Company Reg, Amourence Supervisor . Staldwood ,

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l LIST OF ATTENDEES i i

FOR MEETING HELD ON DECEMBER 11,1997  !

)

N6ME AFFILIATION {

M. D. Lynch NRR/PDill 2 i Edmur o SuWyan NRR/DE/EMC Robert A. Capre NRR/DRPW/PDill 2 '  ;

Brian Sheron NRR/ADT  :

Tim Tulon Comed Braidwood 8tn Jim Meister Comed Braidwood 8tn John Hosmer Comed VP Env John Blomgren Comed 84 & RPV Mgr Roman Gesior Comed SgRPV l Denise Saccomando Comed NLD Mike Sears Comed Braidwood Eng i Hany Smith Comed 86RPV Jack Strosnider NRC/NRR/DE Stephanie Comn NRC/NRR/DE/EMCB Andrea Keim NRC/NRR/DE/EMCB Jenny Weil . NRR/DE/EMCB Phillip Rush NRR/DE/EMCB

! John Tsao NRR/DE/EMCB Cheryl Boardslee N tR/DE/EMCB J

9 4

5 ENCLOSURE 1 t

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_ - . . . . . . . . , . . _ .._--......-.,..-.m... m . , - ,. . _ . . _ . , , - . _ . . . . , _ . . . , . _ . . _ . , _ .

i Comed /SRC Meeting on Braidwood 3.0 Volt IPC Assessment 1

i t

i l Rockville, MD December 11,1997 i

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t 1

N 1 l

Agenda

- Introduction J. Blomgren

- Meeting Objectives J. Blomgren

- Comed Conclusions J. Blomgren

- Braidwood 1 Full Cycle Justification R. Gesior i - Direct Approximation of Leak Rate R. Gesior

- NRC Letter Response J. Blomgren

- Conclusions J. Blomgren 1

I

? -

l

~

i

! Meeting Obj. ectives .

. i

Responc to NRC Letter Dated November 13,1997

Obtain NRC Concurrence with Braidwood 1 Full l Cycle 03eration  !:

i i

l

,- - ,y - ... _ .- ,,

.l July 23,1997 Meeting Braidwood 1 Root Cause Evaluation Results -

Benchmarked Method On Cycle 6 Data l Predicted Braidwood 1 EOC-7 Leakage at MSLB is 57.1 gpm (Room Temperature)

Conclusion i

! Steam Generator Tube Integrity Requirements Met at EOC-6 and EOC-7 Submitted DEI Tech Spec Change to Reduce

! Limit to 0.1 ci/g

~

~

.l -

I Issues Identified by the XRC Insufficient Data to Support Voltage Dependent

Growth Methods

- Can We Predict Cycle 7 Growth?

Justify MSLB Predicted Leak Rate Current DEI Level is not Conservative t

~

i

( .

L Comed Conclusions ~~i

! - For US ARC, Growth Does Not Exceed 10 Volts / EFPY -

Distribution of Growth is Predictable l .

Leakage is Conservatively Bound at 122 gpm i

Braidwood 1 is Safe for Full Cycle 7 Operation l - Dose Equivalent Iodine Limit has been

Administratively Reduced to 0.05 ci/g l - Braidwood Tech Spec Change Will Be Supplemented -

i to Reduce Dose Equivalent Iodine Limit to 0.05 ci/g L .by January 15,1998  !

c L .

l .

j

Braidwood 1 Full Cycle Justification  :

Braidwood I has been Operating in Comphance with Steam

~

Generator Tube Integrity Requirements of 10CFR100 & GDC 19 Basis Analysis of World-wide Data on ODSCC at TSP Concludes .

that Growth is Bounded and That Bounding Growth Varies '

! With BOC Voltage '

I

i

~

i i

I

~

i 4

I

.  :. r How Does ODSCC TSP Growth Behave Exponential t

[ ,e Bounded -

y e / >

! o -

! Voltage Dependent  :

i 4 i

! BOC Voltage i

~

Conclusion:

Based on Comed and Industry Data ODSCC

! TSP Voltage Growth Has an Upper Bound

.~. ,

Brakfwood Unit 1 Cycle 6 Growth (EFPY) - SG C + Largest Growth in SG A Vs. BOC-6 VoMage 9

r .m p %3 m largest Growth in SG A (3rd largest in AN SG*s) m 7

a '

6 e 1 A '

I w

}$

$ A a a i

4 a a a 4

I a a t 2 aa aa A o .

• a

,3 -

{ AAA k  !

O a g A a a l A a a A Aaa '

A a gAd 4 aj a a

1. 4Aa A 3 a 9 _ _ _a A d W M _k_k A AA a aa i l a a ,a haa A

a "

gA aa a* ,  !

i

-1 0 i 0.5 1 1.5 2 2.5 3 soc s voltage

Conclusion:

Braidwood 1 Growth < 8.0 Volts /EFPY During Cycle 6

.l I

12.997 I:.28 nt Cre6.x9: De0C n anysMh ,

.~.

Comed Bounding Gmwth Rates, Growth Vs 90C e Brwd Cyde 4 (1 VoM IPC)

= Brad cyde 5A(1 vonIPC) 12.00 A Bmd Cyde 6 Q Vot IPC) -

x synm Cyde 6(1 vatIPC) xsymn Cyde 7s Q von ec) 11.00 10.00

[ 9.00 3

~ .

t E 2 1 y 8.00

- x x a

3 7..

X A x 6.00 -  ;  ;

x a a X 5.00  ;

ag x a a a

• . a a a n a as 4 on . ,a 0 0.5 1 1.5 2 2.5 3 von.

Conclusion:

Comed Growth Bounded 9 Volts / EFPY K SNWS:ComEdGrowth.XI.S. Comed Dets Chart 12MW979.35 AM

+ sme cyde4 (1 vonIPC)

Comed and U.S. Bounding Growth Rates, Gmsth Vs BOC e e,wd Cyde 5A(1 von WC)

Aemdcydee o vonsc) x syvon Cyde 6(1 vonIPC) 12.00 --

x syvon cyde 7e p voaIPC) e 7F Plant (2voaIPC)

is co + 3M* PM (1 von FC) 10.00

~

t e.co g .

~ e -

8 e i

g 8.00 x i . x .

l 9 s + ^

A g 7.00 x

A x s.oo a 2  :

.

• A ,

' x A A x 5.00-

+

A X A A A

,o A A "

4,g e A A A A A 0 0.5 1 1.5 2 2.5 3 socvenees,vous

Conclusion:

U.S. Plant Growth Bounded by 10 Volts / EFPY -

K sgryr.MFStomEdGrontuds.US Data Chart 12MW977:11 AM

Combined European Data, Growth Vs BOC (BOC< = 3 Volts) 12 .

11 a 10

+

> a >

k9 m

5 e "

>o 8 x

i I

• o7 o

E x .

6 m-x ,

" s a " x  !

5 - a e I  !

• f a

X * "-

4 a _

t 0 0.5 1 1.5 2 2.5 3

Conclusion:

Gmwth Bound at < 12 Volts /EFPY

l '

l' \

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t

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• g D + x M a dN t

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7, s O 3 x y

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( #x y

t w

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xx .. t s

V h

t w

h~

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o r M = ., ol t r o G - "x. ,F. 6 EuV 3 a

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i n-x h5 t

a x IU. t I

Wn 1

D .

_ g/=. hi t g n . = wn a ois r

e = x - e Ga .er p

o =*, -

4 S.

c r co + Ui n u no / aet E I I l I '

t l'i l l dnos v ~ "

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=

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b U= f . 2 i

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=

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n C .

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u

+ c n

0 c C

5 0 5 0 5 2 2 1 1 -

>.g=;5>je

!1l\llllfll!llliilllI LlI

Braidwood 1 Full Cycle Justification Braidwood I has been Operating in Compliance with Steam

. Generator Tube Integrity Requirements of 10CFR100 & GDC 19 Basis .

World-wide Data on ODSCC at TSP Concludes that Growth is ;

Bounded at Approximately 11 Volts /EFPY for BOC Voltages <

5.0 Volts .

Distribution of Growth is Predictable

\

t 9

?

gp -

3 I

U S

> o * = g 1  : >

f d

• 4ld e

4.s g d-e f

3 d #

4 4 e d a

e

• 4s e g 4 l

q

<<l.

g*4

<1 4 0 '

=

g*

1 *

.J i ,

e e k

a r o 8

'S S 3 0 * * *

• N o 4 g Add 3MioA '4WoJD -

3 D

o oo o o o I o

o g+ o

% o oo o o o o')d 'o ,o g

o o o& o >

s o

%: Ie o* *<> d e

> o o l

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5 o Ci r-- f) -

o

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4 o k -

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,,8 o

o

]6!

'g a ko E 3

b 2 o U S S 3 D 4 g

AddEls)loA 'yWoJO -

4 l

Cycle 12 ipOC Vs. Growth Vohs 1 EFPY  :

18 l

16 l* 12 M h / E%

• 1 o -

i 14 i t

• l 1 12  ;

1 r 8-

• e

u. 10 ,

W

, 'a  ;

z  :

o 8 4 * + l 4

g .

2 6

• _

! O ** *

! . + +

4 ^ ^

• w , #  !

• e e  ;

0 *

-2 e

. 0 2 4 6 8 10 12 14 -

BOc voltage, volts

Conclusion:

Distribution Continues to Grow to Higher Voltages 32wrsorm- ce,mieri2 .

i <

t

.e Brakfwood Unit 1 All SG's BOC-4 Voltage vs. Cycle 4 Growth 18.00 16.00  !

14.00 12.00 g10.00 m

, 3. .

2 o *

$ 8.00 o

f i j 6.00 ,

a o

4.00 o ,

O O m O 8 0 2m - *" a8 -

0 00 -  % ,% 0 l

-2.00 . .  !

O.00 0.50 1.00 1.50 2.00 2.50 3.00 BOC-4 Voltage, Volts 12997 5:33 PM cycemcwegr* Ch DOC vs. pose se SCe

j Braidwood Unit 1 cycle a Growth (EFPY) - SG C + Largest Growth in SG A Vs. BOC-6 Voltage t

18 r

l A SG-C (AN IndicsWiorts) i alargest Growth in SG A (3rd t.argest in AN SG's) 14- t i

12 i

!!' 10 E  !

^

8 a 1 E a O

! e a 3 6 a a a K

u A A 4 .

A_A A A A g AA A AAA A

^ A- A 4 2 - A 0 " A A A a

-2 ,

0 0.5 1 1.5 2 2.5 3 soc.s vonese

Conclusion:

Braidwood 1 Growth < 8.0 Volts /EFPY During Cycle 6 829/97 $23 Phl Ccv4 tb ChBOC es perth

O

. o Industry CPDF Growth Function for BOC Voltage Ranges l

-+-CPDF 0-1.0V i 0.9 -

-e-CPDF 1.0-1.5V _

-*-CPDF 1.5-2.UV

-w-CPDF 2.0-2.5

-o-CPDF 2.5-3.0

-*-CPDF 3.0-3.5 0.7 r -e-CPDF 3.5-4.0 -

ii

%s q

0.6 ,

u. '

l

@ 0.5 u .

4 j

04 p if h i

0.3  !

1  !

t 0.2 t

I 0.1  ;

i 0

• i

$9 5 $ 5 5 O $ $ 5 $ $ O O 5 $ $ O $ 5 h O O $ 5 h o? $ 0 $ s ,

Growth Rate,VoltstEFPY I r i

Conclusion:

Modest increase in High Growth Frequency with increasing BOC Voltage up to 4.0 BOC Volts - '

12997 736 PM sedelm We Ch at dein CPDF <1 DV

Braidwood 1 Full Cycle Justification

[

Braidwood 1 has been Operating in Compliance with Steam

Generator Tube Integrity Requirements of 10CFR100 & GDC 19

Basis .

i i

World-wide Data on ODSCC at TSP Concludes that Growth is .l -

s

!' Bounded at Approximately 11 Volts /EFPY for BOC Voltages <

li 5.0 Volts -

i i

Distribution of Growth is Predictable  ;

i 4 -

Method to Predict EOC 7 Distribution Benchmarked on 6 Comed and 1 Foreign Steam Generator

- All Predict Conservative Distributions j b

i =

o ,

Mont A SG-1 EOC-12 Voltage Distribulkm Using Cycle 12 Voltage Independent Growth Rates e

1400 OfTubes Prodcted WActuoi 1200 i

l <

l-i 1000  ! i l

C f t o

3 i I

5 c

, i o 4 s.

i f, e00 __ _

E Z

j 6 - -

l l

200 - - - -

I l

I l

. 0 . . . . .

P. r. n. . . .

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Iw 21 22 23 24 25 26 27 28 29 l i

EOC-12 Voltage, Volts I

! 12ewss3m es ch ert2 er t2snsMh>p y

Plant A SG-1 EDC-12 Voltage Distribution Using Cycle 12 Voltage hiependent Cwowth Rates 1

SO  !

DPredided WEOC-12 Adual 50 - -

4 E

e 1

E 2o 30 -

20 -

10 -- - - - - -

[

0 .

" " " " ~ " " "

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 EOC-12 Voltage, Volts j l

12m7 ese AM  ::h ce2 w cyt2 weendymei

i .'.

l Phmt A SG-1 EOC-12 Voltage Distribution Using Cycle 12 Voltage Dependent Growth Rates, BOC Cutoff 8 Volts 45 DEOC-12 Predk:ted aEOC-12 Actual 40 _

35 --

, 30 .

I 8 l ii l

g 25 - - -

i S

o g 20 - - - ] i

! .o  !

E -

5 15 - - -

1-'

i 10 - - - - - I 5- - - - - -

0

• 10 11 12 13 14 15 16 17 18 19 20 21 22 3 24 25 26 27 i . .

EOC-12 Voltage, ~40tts Conclesiort Voltage Dependent Gro#h WU cAciogy is Be awnarked Using Cycle 12 Voltage Dependent Growth I Rates on BOC-12 with 81 Indications in the Highest Bin i

.! 12957 905 Amt th er12escyt",4..J ^. , Ti k

l

[

Braidwood 1 Full Cycle Justification e l Braidwood I has been Operating in Compliance with Steam  :

L Generator Tube Integrity Requirements of 10CFR100 & GDC 19 -

[ Basis j . World-wide Data on ODSCC at TSP Concludes that Growth is l Bounded at Approximately 11 Volts /EFPY for BOC Voltages <

5.0 Volts  ;

Distribution of Growth is Predictable

i

- Method to Predict EOC 7 Distribution Benchmarked on 6 Comed and 1 Foreign Steam Generator

- All Predict Conservative Distributions l l -

MSLB Leakrate at EOC 7 Bound at 122 gym .

4 f

I i  ;

Brakfwood 1 SG C EOC-7 Leak Rate Sensitivity to Variation in Top Bin Cutoff and Number of i Growth Points in Top Growth Bin 140 120 k Approx. 50 Points Required for Statistical Segneficance

^

100 w l-+-IRB LR. (gpm)l 3 Growth Points in Top Bin Cutoff at 2.3 VBOC

$a. 80 l =

l I*J 80 210 Growth Poird in Top Sin Cutoff at 1.1 VBOC GL 95-05 Guidehnes 40 20 l

0 . . . .

0 0.5 1 1.5 2 2.5 BOC Voltage at Top Bin Cutoff

Conclusion:

122 gpm Leak Rate is Justified 12/997 724 PM tdneeneRMiyAs Ch IRS LR SonenMey

Braidwood 1 Full Cycle Justification Braidwood I has been Operating in Compliance with Steam Generator Tube Integrity Requirements of 10CFR100 & GDC 19 Basis i

World-wide Data on ODSCC at TSP Concludes that Growth is Bounded at Approximately 11 Volts /EFPY for BOC Voltages <

5.0 Volts

- Distribution of Growth is Predictable

- Method to Predict EOC 7 Distribution Benchmarked on 6 Comed and 1 Foreign Steam Generator

- All Predict Conservative Distributions

- MSLB Leakrate at EOC 7 Bounded at 122 gpm Tech Spec Change to Reduce Dose Equivalent Iodine to 0.05 ci/g will be Submitted by January 15,1998

~

X..

Comed Conclusions

- For US ARC, Growth Does Not Exceed 10 Volts / EFPY

- Distribution of Growth is Predictable

- Leakage is Conservatively Bound at 122 gpm

- Braidwood 1 is Safe for Full Cycle 7 Operation

- Dose Equivalent Iodine Limit has been Administratively Reduced to 0.05 pei/g l

- Braidwood Tech Spec Change Will Be Supplemented to Reduce Dose Equivalent Iodine Limit to 0.05 ci/g by January 15,1998

-1 .. .

~

Direct Approximation of Leak Rate Cycle 6, 3.0 Volt Cycle 7, 3.0 Volt Repair Criteria Repair Criteria I

Majcrity ofCycle 6 Leakage from Ind.'s Vooc 1.0 to 3.0 V h

Number of BOC-6 Ind.'s 298 Ind.'s . Leak Reeis Vooc 1.0 to 3.0 V 11.5 gpm v

Number of BOC-7 Leak Rateis 661 Ind..s

• I n 's 26 gpm Vooc 1.0 to 3.0 V Cycle 7 60 Days Cycle 7 Longer than Cycle 6

= Leakage 30 som

Conclusion:

Direct Comparison of Braidwood Cycles 6 and 7 Provides Reasonable Assurance Cycle 7 Leak Rate is Justified

+ .O e a,

. t Comed Conclusions

}

l For US ARC, Growth Does Not Exceed 10 Volts / EFPY Distribution of Growth is Predictable I - Leakage is Conservatively Bound at 122 gpm

- Braidwood 1 is Safe for Full Cycle 7 Operation

- Dose Equivalent Iodine Limit has been Administratively Reduced to 0.05 ci/g

- Braidwood Tech Spec Change Will Be Supplemented to Reduce Dose Equivalent Iodine Limit to 0.05 ci/g by January 15,1998

I '

i

.i

+.

U.S. Vs. European ODSCC ECT Data Normalization Comparison .

l United States And European Normalization Was Evaluated By EPRl:

l - EPRI NP-7480-L Volume 1 For 7/8" Tubing 4

- EPRI NP-7480-L Volume 2 For 3/4" Tubing I l

Procedure For Normalization Of Voltages: *

- Voltage Amplitudes Between U.S. - ASME And European Standards Were Evaluated

- Regression Analysis Performed To Calculate The Voltage ,

Conversion Factor To Apply To The European Data Vus = Ve 6.69 - 0.97 i -

Comed Confirmed Conversion With Re-evaluation By EPRI NDE Center

.