ML20216C899

Summary of 980326 Meeting W/Util in Rockville,Md to Discuss Licensee Plans for Inspecting SG Tubing in Upcoming Refueling Outage

ML20216C899
Person / Time
Site:	Calvert Cliffs
Issue date:	04/10/1998
From:	Dromerick A NRC (Affiliation Not Assigned)
To:	NRC (Affiliation Not Assigned)
References
NUDOCS 9804150096
Download: ML20216C899 (77)

Text

April 10, 1998

., ' LICENSEE: Baltimore G:s cnd Electric Company FACILITY: Cciv:st Cliffs Nucleir Power Plant, Unit N:s.1 cnd 2

SUMMARY

OF THE MARCH 26,1998 MEETING REGARDING .

THE CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NO.1 - 1998 STEAM GENERATOR TUBE INSPECTION ~

On March 26,1998, the Nuclear Re' gulatory Commission (NRC) staff h'eld a meeting at the NRC offices in Rockville, Maryland, with representatives from Baltimore Gas and Electricn Company, the licensee for Calvert Cliffs, Unit No.1, to discuss the licensee's plans for inspecting steam generator tubing in an upcoming refueling outage.1 Representatives from Aptech Engineering and Framatome/Rockridge Technologies were also in attendance at the meeting to support the licensee's presentation. The primary focus of the meeting was to discuss the licensee's performance-based approach for inspecting tubes for " upper bundle freespan degradation." This list of meeting attendees is included in Enclosure 1. Enclosure 2 is a copy of the slides presented by the licensee and its representatives at the meeting.

In the 1996 Calvert Cliffs, Unit No.1, refueling outage, the licensee plugged a number of tubes containing freespan indications. The majority of the freespan indications were confined to tubes in an area of the steam generator termed the upper bundle region. The licensee and its vendors have developed a performance-based inspection plan for the region in the upcoming outage that relies on bobbin coil and plus point oddy current examination techniques. Based on the performance of the inspection techniques and the findings from the tube examinations, the licensee will evaluate the need to expand the inspection scope in the upper bundle region to ensure adequate margins for tube integrity through the end of the next cycle of operation.

At the conclusion of the presentation, the NRC staff stated that the licensee's plans for addressing the upper bundle freespan degradation appeared adequate. However, the staff also noted that inspection results and performance of the inspection techniques with regard to their abilities to identify indications in this region may necessitate reconsideration of the examination scope during the inspection.

Original Signed by:

Alexander W. Dromerick, Senior Project Manager Project Directorate 1-1 Division of Reactor Projects - 1/11 Office of Nuclear Reactor Regulation Docket No. 50-317

Enclosures:

1. List of Attendees

2. Meeting Handouts cc w/encis: See next page DOCUMENT NAME: G:\CC1-2\032698.MTS O To receive a copy of this document, indicate in the box: "C" = Copy without attachment / enclosure "E" = Copy with citrchment/ enclosure "N" = No copy n

- l 0F FICE PM:PDI 1 _ l LA:PCI-1 M I D: POI 1 fM l l l7

.lNAME ADromerick/lecAlf 5LittleV SBajwa 8'A lDATE 04/f$/98 F 04/ Q /98 04/9 /98 04/ /98 04/ /98 Official Record Copy fi$ IIu.A

" "i N W W dr" ogr3 9804150096 900410 PDR ADOCK 050003 7 P

g, lk' Meetina Summary Distribution: Dated: Apri1 10,1998 LICENSEE: Baltimore Gas and Electric Company FACILITY: Calvert Cliffs Nuclear Power Plant, Unit No.1

SUMMARY

OF THE MARCH 26,1998, MEETING REGARDING CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NO.1,1998 STEAM GENERATOR TUBE INSPECTION E-Mail (w/ encl.1) Hard Coov (w/all encis.) i S. Collins /F. Miraglia (SJC1/FJM) Docket File B. Boger (A) (BAB2) PUBLIC J. Zwolinski (A) (JAZ) PDI-1 R/F S. Bajwa (SSB1) A. Dromerick S. Little (SLL) OGC T. Martin (SLM3) ACRS H. Gray J. Muscara S. Coffin ec: Licensee & Service List P. Rush E. Debel B. McCabe (BCM) l t

y- LICENSEE: B:ltimore G:s cnd Electric Comp:ny FACILITY: Calvtrt Cliffs Nuclerr Power PI:nt, Unit Nos.1 cnd 2

SUMMARY

OF THE MARCH 26,1998, MEETING REGARDING THE CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NO.1 - 1998 STEAM GENERATOR TUBE INSPECTION On March 26,1998, the Nuclear Regulatory Commission (NRC) staff held a meeting at the NRC offices in Rockville, Maryland, with representatives from Baltimore Gas and Electrien Company, the licensee for Calvert Cliffs, Unit No.1, to discuss the licensee's plans for inspecting steam generator tubing in an upcoming refueling outage. Representatives from Aptoch Engineering and Framatome/Rockridge Technologies were also in attendance at the meeting to support the licensee's presentation. The primary focus of the meeting was to discuss the licensee's performance-based approach for inspecting tubes for " upper bundle freespan degradation." This list of meeiing attendees is included in Enclosure 1. Enclosure 2 is a copy of the slides presented by the licensee and its representatives at the meeting. . .

In the 1996 Calvert Cliffs, Unit No.1, refueling outage, the licensee plugged a number of tubes containing freespan indications. The majority of the freespan indications were confined to tubes in an area of the steam generator termed the upper bundle region. The licensee and its vendors have developed a performance-based inspection plan for the region in the upcoming outage that relies on bobbin coil and plus point eddy current examination techniques. Based on the l

performance of the inspection techniques and the findings from the tube examinations, the j

licensee will evaluate the need to expand the inspection scope in the upper bundle region to  !

ensure adequate margins for tube integrity through the end of the next cycle of operation.

l At the conclusion of the presentation, the NRC staff stated that the licensee's plans for addressing the upper bundle freespan degradation appeared adequate. However, the staff also noted that inspection results and performance of the inspection techniques with regard to their abilities to identify indications in this region may necessitate reconsideration of the examination scope during the inspection.

Original Signed by:

Alexander W. Dromerick, Senior Project Manager Project Directorate I-1 i Division of Reactor Projects -1/ll i Office of Nuclear Reactor Regulation Docket No. 50-317

Enclosures:

1. List of Attendees

2. Meeting Handouts cc w/encls: See next page DOCUMENT NAME: G:\CC1-2\032698.MTS To receive a copy of this document, indicate in the box: "C" = Copy without attachment / enclosure "E" = Copy with rttachment/ enclosure "N" = No copy n l 0FFICE PM:PDI 1 l LA:PDI 1 @ l D PDI 1 pp[A l l l l l NAME ADromerick/tecAlf Stittle V Stajwa #% l lDATE 04/f$/98 F 04/ 4 /98 04/'*l /98 .

04/ /98 04/ /98 l Official Record Copy

l y %g

1. 1 p UNITED STATES g j NUCLEAR REGULATORY COMMISSION D.C. 30se6-0001

%, / WASHINGTON April *1Q 1998 LICENSEE: Baltimore Gas and Electric Company FACILITY: Calvert Cliffs Nuclear Power Plant, Unit Nos.1 and 2

SUMMARY

OF THE MARCH 26,1998, MEETING REGARDING THE CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NO.1 - 1998 STEAM GENERATOR TUBE INSPECTION On March 26,1998, the Nuclear Regulatory Commission (NRC) staff held a meeting at the NRC ,

~

' offices 1n Rockville, Maryland, with representatives from Baltimore Gas and Electric Company, the licensee for Calvert Cliffs, Unit No.1, to discuss the licensee's plans for inspecting steam generator tubing in an upcoming refueling outage. Representatives from Aptoch Engineering  ;

and Framatome/Rockridge Technologies were also in attendance at the meeting to support the l licensee's presentation. The primary focus of the meeting w'T to discuss the licensee's performance-based approach for inspecting tubes for

• upper cJndle freespan degradation." This list of meeting attendees is included in Enclosure 1. Enclosurt 2 is a copy of the slides presented by the licensee and its representatives at the meeting.

In the 1996 Calvert Cliffs, Unit No.1, refueling outage, the licensee plugged a number of tubes containing freespan indications. The majority of the freespan indications were confined to tubes in an area of the steam generator termed the upper bundle region. The licensee and its vendors have developed a performance-based inspection plan for the region in the upcoming outage that relies on bobbin coil and plus point oddy current examination techniques. Based on the performance of the inspection techniques and the findings from the tube examinations, the licensee will evaluate the need to expand the inspection scope in the upper bundle region to .

ensure adequate margins for tube integrity through the end of the next cycle of operation.

At the conclusion of the presentation, the NRC staff stated that the licensee's plans for b addressing the upper bundle freespan degradation appeared adequate. However, the staff also )

noted that inspection results and performance of the inspection techniques with regard to their abilities to identify indications in this region may necessitate reconsideration of the examination scope during the inspection. .

Ale ander W. Dromerick, Senior Project Manager Project Directorate 1-1 Division of Reactor Projects - t/II Office of Nuclear Reactor Regulation Docket No. 50-317

Enclosures:

1. List of Attendees

2. Meeting Handouts cc w/encis: See next page

}

y Calvert Cliffs Nuclear Power Plant Baltimore Gas & Electric Company Unit Nos.1 and 2 cc:

President Mr. Joseph H. Walter, Chief Engineer Calver1 County Board of Public Service Commission of Commissioners Maryland 175 Main Street Engineering Division Prince Frederick, Md 20678 6 St. Paul Centre Baltimore, MD 21202-6806 James P. Bennett, Esquire

' Counsel Kristen A. Burger, Esquire Baltimore Gas and Electric Company - -

Maryland People's Counsel P.O. Box 1475 6 St. Paul Centre Baltimore, MD 21203 Suite 2101 Baltimore, MD 21202-1631 Jay E. Silberg, Esquire Shaw, Pittman, Potts and Trowbridge Patricia T. Birnie, Esquire 2300 N Street, NW Co-Director Washington, DC 20037 Maryland Safe Energy Coalition P.O. Box 33111 Mr. Thomas N. Pritchett, Director Baltimore, MD 21218 NRM Calvert Cliffs Nuclear Power Plant Mr. Loren F. Donatell l

1050 Calvert Cliffs Parkway NRC Technical Training Center Lusby, MD 20657-4702 5700 Brainerd Road i

Chattanooga, TN 37411-4017 Resident inspector clo U.S. Nuclear Regulatory Mr. Charles H. Cruse Commission Vice President- Nuclear Energy P.O. Box 287 Baltimore Gas and Electric Company St. Leonard, MD 20685 Calvert Cliffs Nuclear Power Plant 1650 Calvert Cliffs Parkway Mr. Richard I. McLean, Manager Lusby, MD 20657-4702 Nuclear Programs Power Plant Research Program Maryland Dept. of Natural Resources Tawes State Office Building, B3 Annapolis, MD 21401 Regional Administrator, Region i U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406

't Q

LIST OF ATTENDEES BALTIMORE GAS AND ELECTRIC COMPANY CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NO.1 March 26,1998 Name Oroanization Alexander Dromerick NRR-PDl/Il Elliott Flick BG&E i Getachew Tesfaye BG&E {

Harold Gray NRC-Reunion I-DRS Joseph M. Mate BG&E

. Christine D. Palmer - -

FTl < -

John Helmey FTl Richard Marlow Rockridge Technologies Rick Coe SC Edison i Rick Maurer ABB - Combustion Engineering j Brian Woodman APTECH Steve Brown APTECH J. A. Begley APTECH {

Alan Thomton BG&E Anthony Saccavino BG&E Joe Muscara NRC/RES/DET Stephanie Coffin NRR/DE/EMCB Eric Debec NRR/DE/EMCB i

S. Singh Bajwa NRR/DRPE Enclosure 1 I j

BE gg CALVERT CLIFFS

/T 1998 Unit 1 SG Tube Inspection XRC Presentation White Flint, Maryland March 26,1998 i

5aE" ,

Diclosure 2

e

~

)

g XRC Meeting Agenda Calvert Cliffs Unit 1 Steam I Generator Inspection S

1. Introduction A. Thornton

2. Primary Side Activities A. Saccavino A. Eddy current scope B. Inspection protocol J C. Expansion strategy D. Tube repairs E. Insitu pressure tests F. Bobbin POD S. Brown G. Upper bundle inspection A. Saccavino

- Probabilistic model J. Begley

- Basis for inspection B. Woodman

- Condition monitoring J. Begley H. Summary of Examination A. Saccavino

3. NRC Interactions A. Thornton l

NRC0398 3/26/98 2

N Steam Generator Inspection Team BGE: l Al Thornton SG Project Manager Elliott Flick SG System Manager Joe Mate SG System Engineer Anthony Saccavino SG NDE Engineer  !

Getachew Tesfaye SG Regulatory Engineer APTECH Engineering:

Jim Begley Director Brian Woodman SR. Technical Consultant ,

Steve Brown SR. NDE Specialist l Framatome/Rockric ge Technologies:

Bob Cole SG Project Manager Christine Palmer SG Engineer Brian Jones SG Inspection Task Lead '

Mike Dobson NDE LevelIII Lead Richard Marlow SR. NDE Specialist NRC0398 3f262 3

BM gg BackgroundInformation 75

+ CE Model 67 SGs l 8519 tubes per SG tube OD/ wall - 0.75"/0.048" tube material- Alloy 600 HT/MA tube plugs - Alloy 690

+ 15.8 EFPY

+ Thot 594 F (since start up)

+ Plugging history SG 11- 490 SG 12 - 607

=" .

aiE gj SG Work Scope 73 Objectives

• Maintain SG tube integrity between inspections

• Proactively inspect and repair SG tubes

+ Operate full cycle between inspections

• Meet regulatory requirements and commitments

• Apply site and industry experience

g.

M g Exam Preparations

• Site specific degradation assessment site specific degradation experience ,

industry degradation experience eddy current techniques l

+ Site specific eddy current technique validation

+ Site specific analysis guidelines

+ Site specific analysts' exam NRCO398 3/26/98 6

, L, SSE gg Degradation Assessment 75

+ Degradation Mechanisms:

H/L TTS - circumferential &

axial ODSCC Upper bundle free span a~ xial ODSCC l Steam blanket region - axial ODSCC (R 6-13) 9th H/L drilled TSP - axial &

circumferential ODSCC

+ Focus exam on areas with highest  ;

potential for structurally limiting degradation

""2" ,

n.

BGE

/ Eddy Current Exam i

• Bobbin exam - 100%, full length Plus Point Exam:

• 100% H/L top of tubesheet

+

100% Steam Blanket (R 6-13)

• 100% 9th H/L drilled TSP 20% low row E-bends (R 1-2)

• 20% C/L top of tubesheet

• 20% dented intersections

.

• 20% rol:.ed plugs

• E pper Bundle free span -

performance based "O" ,

7, BGE g Expansion Strategy 5

Evaluate the need to expand the exam based on:

eddy current parameters location ofindications indication density metallurgical considerations eddy current probe and  ;

technique capabilities NRCO398 3!26/98 9

C' M

/ Examination Protocol i 4

+ Independent primary and secondary analysis teams i

• Independent utility analysts

+ All analysts are QDA qualified ,

+ Analyst feedback system l

• Primary and secondary data management

""!"" so

1.

BT g Tube Repairs T

+ Repair based on detection or confirmation with a Plus Point probe

+ Plus point data will be used to ,

disposition bobbin indications

+ Tube plugging is the primary repair method

+ Wire rope stabilizers will be ,

installed in tubes containing circumferential defect <

indications

M

/ Insitu Pressure Tests

+ Pressure testing of SG tubes provides valuable data to :

evaluate tube structural integrity benchmark the operational i assessment model

+ Insitu pressure tests will be concucted on 5 - 10 tubes i

+ Tubes will be selected based on eddy current parameters

"":" ,2

BGE

/ Inspection Technology i

-Bobbin Inspection Techniques:- -

• Maximize bobbin inspection effectiveness

• Utilize low frequency screening 1 to enhance detection

• Develop probability of detection :

(POD) curves for enhanced bobbin techniques

• Bobbin technique PODS used to develop upper bundle inspection strategy  !

l

%" e

e c

n 1 a t m i

n oo r n Uf rt i I

c n

s ea g8 t

M9 9 i s

e c

v f

f Pr t E 1 nS r

e i

l l s & 6 G2

, w g o

r n B. ri Can t o B h

/ c D. een Si g n Cr n t

em R a E r NM h c

vme e

e t A

p l

al e D Cp p

u S

e r h 1 u t e d e

i w f s

c c s f

i n er o e l

C a c p b u t r

m n s t e ai v r n ms m l f

oo i rl oan y

f o

r C a

rt f r

ea ea d m p ,

yv e o r

t n mo rt sf d i

t l s i l

el Pr-an i et i bdu s e t n v t

n o s y etsbtseo a

em s myoi n r m E r l

uanpuier6 r c me e D Dt sa ngpsh 9 Nnia o irn ae9 l

h t i b 1 p e s ~ ,a c dgug t a ot p i viedb l erl n t gl oi r u t b od c ar nDTt e a wu S jset Pa CeTd bE + +Em+

Oo .

a

s __ E e.

b_

T.

u.

o cf  !

d e_ 0 l

l e u - - ~. -

P 2

4 e

• 2 e a , j' 1

s f C f

i & C W l

6 S c T C 7 D i

h W  %

t L O 1 ast p hT 9 r 6 p e.4 7 pf n5r a god n e% 9 4

o v R 6 ol oi t n 1 et l

sL s a .

g%

a e1 eati ac a6 l

l n

C b1 et o edM+R e2 a0 u1 r +

TRF Tmio n .

a e e

) ll l .

1 g

i n z r

e l H ght ek i

nti i l

f n n)

B n w o n0 e zsts a0 s ee Ha i

ach1 e

r u rckpm1 x qS d r u na0ai 0ni f x00 i d h ta2b nM( 4 e ceD + Co +

c _T

• e o

r a P g s n l e

s i r zn ght e i

s Hn y ntiif l k a i

n h a Anw l

e zsts i0 o0c n ee a u r Haa2t A qS ckpm&a d r d i

n ta0a 0ni0w f n0a h

c a2b+ o1r C +

eD T e e a

lll

i l l d

e g

g e n u s o l p

l a

? i t e f s c t a t el s6 r e e r a

l 9 e r a9 t

u e el l c1 w o

q dt al e a s g" l

i nr acl n el ecl n h eA v

h el s ef ai t t ae c w al a s au r h u e t cf l a

l al u t q T b eer s e f ia" t

r nvs t oi n

l h e e ealyh o f f agwt i

of h o or t e e c e

w ed -

l p y Pk T T

i d n - -

- rb+

l n

y aaD r D fo d g Ba t yO eht h t P O e en hi P ni u Wib l b

si l

ah r

e re nmui cis e r s n a qet r

ab i gwdoieeh cl l sr oHL t vt eb E poo E dt u Tc ea a e e 1

I!

• a l

e p

i t

l u

m n s o t g i t

n s)e n c i

u s a t s v de p ydgie

)c i g o ri c

i i

cl ar nk acZo(

t e m s

t pt ear c

t a r

1R ( its e s i

sp a t t l s ai s s _

P st ymy m

isniy l n l Us y and ese arl D

no a s

l an n _

P aA n nt a Ay r e f

S f i

pm2 a0d e n l

Cya ei f t o _

r d d t o ai t .

c u t an s _

r emoi nel apo i

l l _

l vic r e eDtou s e _

aPS vOTDr i

. e C eeFP _

a e

O o

b e

e c r , l a

p t

u h c .

t i

u r

w t d e

S i x

g m m n s r e

a i t

s e t r e n n g t i

l e

i a

o D g d a gt a r Pi n i u t nd P S n Gnd ai s be t

nf i a o D oo r s ie e u i i s s c P t c s eT eysiTt r

t S uotp s u a ect l s s d e a d yt n b a r yl or r u a cA l

a Pl a ua l t t P nL e+L + nPd i

n eA. . A

• e e e

0 0 _

1 _

t s y 0

8 l

g ,

u j W s b e - 0 6

T e o .

r ht .

P y p e .

n D R

i b

b

< xc i

hp o a B ' ,

r g

o D g 0 0 8

5

,t 4 l

l t

a 4 e

, $)

^

M O [ /

P l # ,l 6, ,

o

' 0

' 2

'{

D r,D P + ,

y',

I 0

S 1 8 0

6 0

4 0

2 0

f

> 0 n

x x

• 4 x 5 X 3 F o o o

• s s s E

R _ + R- R ,' Re

• e e n I 8-5Q

l BE ft Upper Bundle Exam l 7%

Overview -

• Maintain acceptable probability of burst safety margin

• CCNPP SG multi-cycle model i

+ Predicts 1998 condition based on previous inspection results l

• Applies site specific PODS Predicts probability of tube burst and leak rate

• Provides for validation based on 1998 exam results

=" ,4

BG g Upper Bundle Exam I

\

+ Consists of the arc & stay dome from the sixth H/L egg crate to the vertical middle strap i

+ Base Scope:

100% Bobbin exam 50% upper bundle - Plus Pt.

100% H/L 9th TSP - Plus Pt.

+ Fallback Scope:

100% Bobbin exam 100% upper bundle - Plus Pt.

100% H/L 9th TSP - Plus Pt.

l 15

SSE j Upper Bundle Exam y Implementation  ;

MN 16

\

s OPERATIONAL ASSESSMENT OF CORROSION DEGRADATION AT CALVERT CLIFFS UNIT 1

~ ~

J. A. BEGLEY

= OVERVIEW OF DEGRADATION AND PROBABILISTIC MODELS

• FREESPAN DEGRADATION INSPECTION SAMPLING OPTIONS

• CONDITION MONITORING AND SAMPLING OPTION DECISION POINTS l

l

~

R APTECH eee,~eem,~esee J

i l

UNIT 1 1996 INSPECTION RESULTS Location Indication Tvoe S/G 11 S/G 12 TTS sal, MAI 116 166 TTS SCl, MCI 56 33 9H sal, mal 15 5 9H SCl, MCI 2 5 Freespan sal, mal, MSI 164 391 J

l APTECH eseiseesiseseev,cee . . _ _ _ _

O 4

MULTI-CYCLE SIMULATION MODEL

• INITIATION

~

GROWTH DETECTION SIZING REPAIR e REPEAT FOR MULTIPLE CYCLES OF OPERATION

. BENCHMARK MODEl.

COMPARE PREDICTED VERSUS OBSERVED NUMBER OF INDICATIONS DISTRIBUTIONOF EOC DEPTHS, LENGTH, ETC. j l

• PROGRAM KEEPS TRACK OF DETECTED AND '

UNDETECTED CRACKS l

• PROGRAM SIMULATES "REAL" CRACK SIZES I e "REAL" AND " MEASURED" CRACK SIZES ARE FOLLOWED e EOC CRACK SIZE " MEASUREMENTS" ARE PREDICTED e BURST AND LEAK CALCULATIONS BASED ON "REAL" SIZES OF BOTH DETECTED AND UNDETECTED CRACKS l flPTECH e~e,~ees,sese-,a . _ .

EERPTEG N NG SERvlCES 4M I

i Normalized Burst Pressure vs Plus Point Volts 12000 l 10000 0 -

Yo so o - i

,+ i o

g 8000 -

< i

.E E

n.

E 6000 - --

a i m

! l i

ea E

$ 4000 ,

2000 i

0 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 0.00 Plus Point Volts, Vpp

EEdRPTECHI 6 NEERING SERvlCES,INC.

. .E--

1.0 0.9 B E F

i I  !

0.8 --

/. .

0.7 - - - .

I O

! l  :

@ 0.6

. 7

.$ f i f I i b 0.5 b

• I '

b E .'

D l O.4 -

D- h I

0.3  !

l I

> } ,

i A Pluspoint j 0.2

i B CC/SPD/B j

! C CC/SPD/C l i l D SG/SPD/AG E SG/SPD/E 0.1 '

F BP/ TSP ,

i i j G BP/STL j i

I '

0.0 )

0 20 40 60 80 100 Maximum Depth, %TW

s t

EOC Plus Point Voltage Distributions, Freespan indications I l

1.0  :~- , ._

~

! l' '

0.9 Y f '

I ~

f ~,

l ,

t t ,

~,

- /?

~:

^

J

'l' f "e 1.q ' . a 0.8 -

,b .-

~ c. -

- n.- ;g.: . ..

( ' ^"

<?c' p ,> j , []; ' , , . . , .

r +

j '

~'

~

.- v H 0.7 4 .s 4

w

) '.

, i O.6

/#

d, -

I - .

l. - .

u. ,j -l , ,

~

'I 0.5 .

r .,

y' .. ~

g  ;,  : .

I

' < Plant A, MC

$ 0.4 J

I-a Plant A, MC d> if,. m L:

,E,

~,

m. ;- .%, 7:; , - .

y Plant B, FC

~ a w

' -i "' " W' -

--- Plant B, FC ,

0.3 ..

I 4

,: p e, .. t r. Plant B, FC 7~ .

.I *

~

',- j " :p ' : < ~9'k ' . Plant B, FC -

.,~

%. "A Plant C, FC 4 0.2 -- i/ -b.' ' -

+

• - Plant C, FC k

er1 y;i,w , , }y ,

Plant C, MC

-j .

i Plant C, MC 0.1 --

>f* CC U1 SG11996

,o:f- W e

, c;w

~,

n '

CC U1 SG21996 f

J (-

q m'

.- ;g;

, , - ~

~

~ ,c: ,

0.0 0.00 0.50 1.00 1.50 2.00 Volts

s BOBBIN PROBE PROBABILITY ,

OF DETECTION SUPPLEMENTAL PERFORMANCE DEMONSTRATION PROGRAMS - FREESPAN INDICATIONS l_N 0.048 INCH WALL THICKNESS TUBING e INSPECTIONS WITH BOBBIN. PROBE CAN HAVE AN . .. . ,

EFFECTIVENESS ABOUT EQUAL TO USE OF THE PLUSPOINT PROBE e SOME PRIMARY / SECONDARY / RESOLUTION ANALYST TEAMS ARE NOT AS EFFECTIVE AS OTHERS ,

REVIEW OF AXIAL FREESPAN INDICATION PLUSPOINT VOLTAGE DISTRIBUTIONS

• IN SOME CASES BOBBIN PROBE ONLY INSPECTIONS SUPPORT FULL CYCLE OPERATION ENGINEERING SERVICES '..

ISAPPLIEDTECHNOLOGY BASIS FOR FREESPAN ODSCC INSPECTION PLAN:

CALVERT CLIFFS UNIT-1 i

BRIAN W. WOODMAS~

APTECH ENGISEERISU SERVICES WHITE FLIST MARCH 261998

- ,< m . m o o . E = fs a i!"u = ' a i = r s t ',"J a ,,o ,,m . , -

eousa"1"7A"*a's"""dene'#"

c me cu e "2 2 &'? & *& **:3 ; o " 2 E s e 87 G YE L

t OUTLINE OF DISCUSSION l

IXTRODECTION

- SINULATION OF INSPECTION

- ODSCC AT FREESPAN LOCATIONS

- GENERAL STATUS OF CC-1 DEVELOPMENT OF INSPECTION SIMULATION COMPARISON STEDIES FOR BASIC INSPECTION STRATEGIES COMPOU.SD PLUSPOTST/ BOBBIN INSPECTION

t INTRODUCTION:

SIMULATION OF INSPECTIONS MELTI-CYCLE RCS TIME MODEL E SED INSPECTION MODELE EPGRADED TO SIMELATE MORE COMPLEX INSPECTION STRATEGIES QUANTITATIVE RISK COMPARISON POSSIBLE l

t INTRODUCTION :

ODSCC AT FREESPAN LOCATIONS PALO VERDE 2

- TUBE RUPTURE 1993

- DISTINCT RISK ZONE - ARC

- T&H EXPLANATION

- EXTENSIVE HISTORY OTHER CE PLANTS

- CC-1, ANO2, ST LUCIE 1, SONGS

- LESS SEVERE ATTACK

- RISK ZONE LESS WELL DEFINED RISK FACTORS

- DRYOUT REGIONS l

- TUBE SPACING -BRIDGING

. DEPOSITS l

ISTRODE~CTION: STATE ~S OF CALVERT CLIFFS-1 FREESPAN ODSCC CONFIRMED IN 1996 INSPECTION LARGE NUMBER OF DEFECTS NO SIGNIFICANT DEGRADATION IN STRUCTURAL, INTEGRITY :lN-SITU:

PULLED TUBES SHOWED FREESPAN DEFECTS RELATIVELY SHALLOW EXTENSIVE PLUSPOINT EXAM PROVIDED THOROUGH -

l CHARACTERIZATION OF ODSCC ATTACK MODELLING OF FREESPAN ODSCC INSPECTION WARRANTED REASONABLE SPECTRUM OF EXPECTED OUTCOMES

- ATTACK CONFIRMED

- INSPECTION TRANSIENT UNLIKELY

DEVELOPMENT OF l INSPECTION SIMULATION EXTENSION OF CURRENT CC-1 .

RUSTIME :MODEL l 1

MELTI-CYCLE :MODEL

MODIFIED TO INCLEDE ADDITIONAL ' ATTRIBUTE' TO i CONTROL TYPE OF INSPECTION FOR GIVEN i DEFECT: l

- SPATIALLY BASED

- FREQUENCY BASED PERMITS CO:MPARISON OF INSPECTION PLANS BASED ON PROBABILITY OF BURST l I

l BASIC SIELATION:

CALVERT CLIFFS 1 5 CYCLES 1994 12.4 EFPY BOBBIN

- 1996 13.9 PLUSPOINT 1998 15.8

- 2000 17.5

- 2002 19.1 INITIATION MODEL

- WEIBULL : SLOPE = 6

[ CONSERVATIVE: .

GROWTH RATE - LOG NORMAL [ PV-3 CYCLE 5]

POD - RANGE OF POD FUNCTIONS APPLIED SINGLELY AND IN l COMBINATION [ CYCLES 3-5]

l

t POD FCKCTIONS POD FUNCTIONS

- PLUSPOINT 1996- PULLED TUBE DATA - -

- LIMITING

- RESO1 - 1998 SPD BEST:

- RESO3 - 1998 SPD : WORST] i RANGE OF POD FUNCTIONS FOR INSPERTION PLAN 1.0 , - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

l RESOL l 0.8 -

. --LUSfD --

• o

• o Ao y 0.6 e -

y 4

4 RESO3 u o

0.4 4 1 LBUTING 0.2  % + +

o% o PODPP o D PODOB 0 o PODTC 0 20 40 60 80 100 A PODTA DEPTH

COMPARISON STUD 11CS FOR BASIC INSPECTION STRATEGIES SINGLE PROCESS INSPECTION MIXED STRATEGY STRATIFIED APPROACH I

SISULE PROCESS INSPECTION STRATEGY COMPARISON PLE~SPOINT VS. LIMITING BOBBIS~

EACH TECHNIQEE APPLIED IN l 1998,2000 A'SD 2002 INSPECTIONS l E~SE OF BsOBBIX ONLY INSPECTION WOELD REQEIRE FULL PLUSPOIST IN 2000 FOR !

CONTISEED ACCEPTABLE l RISK STEDY SHOWS RANUE OF POD EFFECTS

l I

t COMPARISON OF NUMBER OF DEFECTS : plt SPOINT AND BOBBIN 750 i ,

i '

650 -

~

i -- '

l I .

/

j> , 4 550 .

.,- i /- r ---

i.

I i' ,

! j

! 450 l l

l .! 1 i i i

350 ;- ---- i I

}

i l 1

/[ l t

250 - - - -

x-,

N

./ '

1 a

i b

33o _.

_- h

_j_ .._ _ . _ _

i

! l  % PLUSPOINT

! 1995 1996 4 1997 1998 1999 l

2000 2001 2002 2003 % BOBBIN i

YEAR OFINSPECTION 1

l l

l l

I l .

l l t

l I

i

~

't

. .. I 0.030 BASEUNE PLUSPOINT AND BOBBIN-ONLY INSPECTIONS 1

1, l

a i

0.025 I j-

! a f--

! E '!

d i p 0.020 i

/-L v) .

t t

g 0.015 I -

~~ ~

1 i

s 1 L 0.010 , l-'

I.

l 0.005 ----- I l '

0.000 @ i 1995 1996 1997

% BOBBIN 1998 1999 2000 i

2001 2002 2003  % PLUSPOlt YEAR OFINSPECTION

I l .

l l

l

{

MIXED STRATEGY:

50% SPLIT JLUSPOIST/ BOBBIN: .

PLL'SPOIST INSPECTION FOR 5C% OF TEBES 1998 LIMITING BOBBIN FOR REMAISDER INSPECTION TECHSIQEES REVERSED IN ENSEING CYCLES :FOREVALUATION PERPOSES:

SICiSIFICA'ST IMPROVEME:ST OVER STRAIGHT BOBBIS~

KEEPS RISK IN CO:5 TROL l

% I g

MIXED STRATEGY:

0.030 , .

I f

l l l 0.025 -

e i

,.f s 0.020 - l ,

l m l 3-l g 0.015 l -

E 0.010 '

O.005  :-

j ^asem- * -- -

I e I A l 0.000 " ' '

l 1995 1996 1997 1998 1999 2000 2001 2002 2003 YEAR OF INSPECTION A _ __

I STRATIFIED APPROACH INSPECTION CAN BE DIVIDED INTO REGIONS .OR STRATA TAKES ADVANTAGE OF " KNOWING' WHERE DEFECTS ARE LOCATED

- PLUSPOINT IN REGIONS OF HIGH DENSITY

- LIMITING BOBBIN IN REGIONS OF LOW DENSITY CAN EFFECTIVELYINCTGASE THE SAMPLING EFFECTIVENESS OF THE MORE SENSITIVE DEVICE LOGISTICALLY DIFFICULT TO IMPLEMENT FOR CC-1

3

% )

t i

-r .- * *

• ' . . . . *.. -*... .....e -

2,_.,

STE AM G EN E 1.1 A l'OllS CCNI'P 142

. . .eu r- --

see t/~ 0t 9150 Swerests ,

va l.

~ vu l- ~ve l-

• • \evia..sgevet g *

• * ** CLNite teNE Of SIC AM g,

• gluttATOR Del . ,,

- ' sc ,

., l 4 '

• . .g.

4 ,

, CSS N50

&~ v s x: t 1

50L00 EUPPollf6 .

~

) [ (9410)ere l'tittCK VERTICAL 4 OtAGON AL SUPPORT & (DH.vH.vM.vt.DC)

ARE ALL 4- lHICE *

• ms J .. . v. v. s . ~kS~ ~ ~ '

i

. suost.amestss l

, . .. , . . . ., 1

- 25

- me e, .

I .

s s. .-~ ts e i

pos tro CM8 ttC i surroats a Svercats ., -

as nrs .: f at 49 '+.i . _ - n . t ess: CS surronts e simoucu e 3* >aat src caans easion

=

ne granner.ll.=ar.rr.wsv ,-rs* . s " *s s-s sr. Ce 39' . ,

I Cs I sis ;ra . s. t . r.~-

. . s? *et s * *-E .a..a

- ALL utA5untutWTS =

ARE C/L 10 C/L on fuet surPORis . . . . ce 7

. e semove d.

as = r-

- . . -. cs , 2

- v.sm= !:- ' -

• k' - - / h. . . . . .. . w

- eversutti

. O,y

/ \

ces ._-

aus 4 N

.. .2 ., ,...---.s.<__,,

. <J R ,

• I

- ,f l Rows Contacting Supports Above 6th TS ,

1 piows eso.O( Suet'Ottis surfortt Dt58oNATIONS s.g vu I e se 35 3 fu L vM. OC - -

l 3686 5 lif.tu t vM.DC. CF

• .I e6.F3 7 888. 881. De L vM. OCL CF. CS rom e wL ea ni. cat vu.oc.cr.cs.vc mus u sawt ane.oitvnoc;ct. cave.cs usse  :: umna vitesur.cntvu oc.cr.ctve cs cw STEAM GENERATORS, CCNPP, UNIT 1 AND UNIT 2

1 i

PROBABluTY OF BURST-SLB IMPORTANCE SAMPUNG PLUSPOINT/ BOBBIN 0.020 ,

l 0.015 -~

r -

N --

~l to l 0.010 - "- --

,--- -4 -

e i

f I

0.005 --

-- t

~

% .1 b ,,  ;

'O.000 l 7A l l

% .9

% 1,0 1993 1995 1997 1999 2001 2003 YEAR OF INSPECTION 1

COMPOCSD PLUSPOIST/ BOBBIN INSPECTION PLAXS~ED FOR CC-1 1998 INSPECTION ALTERNATE LINES INSPECTED WITH PLUSPOINT IX UPPER BCSDLE :50/50 MIX:

IMPROVED BOBBIN POD FCKCTIONS FROM 1998 SPD's USED IN ANALYSIS BASIC SIMULATION I PROCESS AS IN CASE STEDIES 1 l

v COMPOUSD PLUSPOIST/ BOBBIN INSPECTION SPD RECENTLY COMPLETED SHOWS  !

HIGH DETECTION CAPABILITY FOR BOBBIN l SECOND SPD TO BE PERFORMED PRIOR TO OUTAGE SHOULD ALSO SHOW SIGNIFICANTIMPROVEMENT IN BOBBIN DETECTION CAPABILITY VIS-A-VIS THE PLUSPOINT PROBE 50/50 PLUSPOINT/ BOBBIN HAS BEEN I SHOWN TO MANAGE RISK EVEN WITH RELATIVELY POOR BOBBIN PERFORMANCE GOOD INSPECTION LOGISTICS LARGE PLUSPOINT SAMPLE TO SUPPORT COMPARITIVE BOBBIN EVALUATION

s a

SPD BOBBIN POD FUNCTIONS FOR VARIOUS TEAMS --

1.0 ,,, ...-

0.8 sol

..' 9'

,i ,'

/ '

RESO3

.i .

0.6 3 .' . -

,i t

O e 0.4 y

/

4

.S 0.2 c ,

//

/!

(i 0.0 0 20 40 80 80 100 DEPTH - %THRUWALL i

l l

l

COMPARISON OF PREDICTED BURST PROBABILITIES PLUSPOINT/ BOBBIN INSPECTION RESO1 AND RESO3 FROM SPD 1 0.006

'g 0.005 -- + +

e {- - -

e E e

@ 0.004 -c --

O 8

M 0.003

'V

--- + ,

^--

i 0.002

-- {

+ i 0.001  % RESO1 1993 1995 1997 1999 2001 2003 % RESO3 INSPECTION l

i r

l

~~V s

1 0.030 4

i 0.025 - " 4 - --- -

b  !

E

_.Wi%_ l

$ o'ogg 8 B0881R

~

g ~ 0.015 t--

$ i d

l 0.010 5

e 0005 - -

,--+ -n- -

.. / ,

, e, 0.000 .

1995 1996 1997 1998 1999 2000 2001- 2002 2003 YEAR OF INSPECTION

\Pl.USf0lMT i

4

1 i

BASIS FOR EXPAXSION TO FALLBACK EXAM COXDITION MONITORIS~G ISSUES

- ADVERSE VOLTAGE DISTRIBUTION

- CS~ ACCEPTABLE EXTREMES

- HIGH APPARENT GROWTH RATES

- LARGER THAX EXPECTED DEFECT POPELATION BOBBININSPECTION ISSUES UXACCEPTABLE FALSE CALL RATE

l l

CONDITION MONITORING l

• NUMBER OF INDICTIONS e CRACK LENGTH DISTRIBUTION

• EOC DEGRADATION SEVERITY (PLUS POINT VOLTAGES, IN SITU TESTING)

• CRACK GROWTH RATE DISTRIBUTION (PLUS POINT VOLTAGE CHANGES, VOLTAGE DISTRIBUTION) l l

I l

! APTECH e~e,~eee,~eseev,cee .___

i 3

~ EEAPTECH w~

PREDICTIONS FOR 1998 CC-1 l'NSPECTION COMPOUNT BOBBIN /Pl.USPOINT

[ UPPER BUNDLE FREESPAN : MOST AFFECTED SG : CONSERVATIVE INITIATION]

2200 2000 --

v) 1800 E -

h1600 h1400

@ 1200 ---

w- 800 -

600 -

m 400 -

200 +-

0 390 410 430 450 470 490 510 530 550 570 590 400 420 440 460 480 500 520 540 560 580 600 - @dd NUMBER OF DEFECTS BENCHMARK FOR 1996 CC-1 INSPECTION PLUSPOINTINSPECTION

[ UPPER BUNDLE FREESPAN : MOST AFFECTED STEAM GENERATOR) 2400  !

2200 -

u) 2000 -

b 1800 - - - - - - - - - - - - - - - - - - - - - - - - - - - -

i:

g 1600 ------ - -

E 1400 --____________

1200 =

i 0

1000 -- -

O 800 -- -------- -

E m e

2

-4 l 400 - -

A 300 310 320 330 340 350 360 370 380 390 400 410 420 430 440 450 460 470 480 490 - @dd NUMBER OF DEFECTS 1

i E$$APTECH

=m.ms.

7 Results

> Projections and Benchmarks ,

i NSPECTION . U2M5-2 3 E

n .

110 - -

1 220 225 230 235 240 245 250 2M 2 h -

5 - - 290 295 300 305 310 315 320 325 330 NSPECTION.02RS ,

M -

l:: -

T l" -g '

i: g l* " d s ,

0 r--------- -il NUMSER OF CRACKS OSSERVED E =5. .

s..

39

, EEAPTECH[

L 6

~ NEERING SERVlCEE (NC.'

Results

> Projections and Benchmarks I INSPECTION.U2R7 [PROJECTEDI 112 104 ..-

$ E,4 ..

"~

8 \

I .$

Il::l --

_ _MI .. _

NUMBER OF CRACKS 08 SERVED INSPECTION.LW -

135 .

i l

126 l 117 -

o 108 -

N" N so i 8 at g

8 l12 a 'x B ,, /E \

m d \ '

i all ll'sh_ -

230 235 240 245 250 255 290 205 270 275 280 285 200 295 300 306 310 316 320 325 330 335 340 345 350 N'JMSER OF OSSERVATIONS 38

I

!!stIur Freespan 80

!=

I 10 -

4

.s T-ONE (RECENT) PREDICTION OF NUMBER OF FREESPAN INDICATIONS WAS UNCONSERVAIJyE e NUMBER PROJECTED = 63

-

• NUMBER OBSERVED = 150 .

I e ASSUMED WElBULL SLOPE = 6 1 (MAXIMUM REALISTIC CHOICE BASED ON PLANT EXPERIENCE FOR ALL TYPES OF CORROSION DEGRADATION AND WELL CONTROLLED LABORATORY TESTS) )

• OBSERVED WElBULL SLOPE = 17.1

. OBSERVED SLOPE NOT CONSISTENT WITH OVERALL PLANT EXPERIENCE AND IMPLEMENTATION OF CHEMICAL CLEANING I

e INSPECTION TRANSIENT IS SUSPECTED DUE TO HEIGHTENED ANALYST SENSITIVITY TO LOWER FREQUENCY CHANNELS ENCOURAGED BY RERCENT SPD PROGRAM e USE OF. WORST CASE POD CURVE AND WORST CASE  ;

CRACK GROWTH RATE LEADS TO CONSERVATIVE  !

CALCULATED CONDITIONAL PROBABILITY OF TUBE BURST -

BUT PROJECTED BlUMBER OF INDICATIONS WILL BE UNCONSERVATIVE 1

1 ENGINEERING S S __.

t E!APTECH G NEERiNG SERvlCES. INC.

.L=

1.0 1

• I A

0.9 -

B 4

0.8 .

i t

i

~ ~

0.7 [

c 0 '

i Ag 0.6 i  :

o au 2

O 0.5 - -

• I N

b 3 -

,8 0.4 !j 7 '

2  !

E ,

t i

0.3 l

' i 4 6

I 0.2 '

i I

l i i 1

0.1 . A Bobbin Log-Logistic -

l l i  ! B Team E Log-Logistic i '

0.0 O 20 40 60 80 100 Maximum Depth, %TW l

l l

l ,

I l l

1

.s -

i .

EERPTECH ommm. m.

CCCPneer

. l 0 ,

I h I /

l

/

e

/

/

/

• /

/

0.8 A' 'I w .3 li l

ICC UI ;

f I

I I

I ,

I I I I l 0.6 I

I e  !

]

. l

! l j i i l

4 l i E

a ,I '

W 0.4 , ,

I h I I f .

r 1 i \

I l l f

I a t ,

l 1 J , 1 0.2

! l

! I I

s l l l

. / j 0.0 '

0 1 2 3 , 4 5 CmekLength(Inches)

t EERPTECH

~

IIIELEll53tr5tilgtIK111tt ecornese

, ,CC ANALYSIS

• ^

,"" :t.". *** ,,,,, ..... -

/>-

l ,...

,o / ...

u. ,I  ; .-

8

./ , .**

• s o

r i e p

• : I e l -! !e t SA -

o o

f -

r r

o  !

o e o o

,e t

, o o  :

', I 2 1 o I 0

e l

g .

f ,1 pgeset A e.4 / ... piam e

,i j ;f lf -.- n.ac

......panet 0 s sl i i/ .-e== Plant E l ll .

2

• o

u. s le:

o *:

l !!

lV t c

.! .l 4

S S le SS SS SS L

seest erew n meen M YsuePPvt i

1

- EEAPTECH

= -,. m Freespan, Plus Point Volts 0.30 ,

+ Unit 2, SG 1 I

o Unit 2, SG 2

+

0.25 o

+

o  ;

+ )

^

0.20 l D +

$ .oo s j*

i e I 'y l o 0.15

!

• o o H

n. +

E 8

+

o* o e 0.10 o

9+o  ?

oo + o; o ++o , +

$ o

++ o ,* 6 0.05 ,, , ,

o+ , o ,(o ++o +

• $ o o**o

• eV *

+

o 0.00

• <o * * ? 8t t + $ +o 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 initial Plus Point Volts, Vi

1 E

Examination Summary Bobbin exam - 100%, full length Plus Point Exam:

• 100% H/L top of tubesheet

+

100% Steam Blanket (R 6-13)

• 100% 9th H/L drilled TSP 20% low row U-bends (R 1-2)

• 20% C/L top of tubesheet

• 20% dented intersections

• 20% rolled plugs

• Upper bundle free span -performance based NRC0398 3/26/98 17

M

/ Examination Summary i

Exam maintains SG tube integrity:

+ 100% Plus Point inspection of areas with highest potential for  !

structurally limiting degradation !

+ E~pper bundle approach maintains

! POB margin:

Extensive 1996 Plus Pt. exam Pulled tube burst pressures Very low probability of burst E se of condition monitoring

• Conservative tube repair policy "0" ,,

,- )

BSE g XRC Interactions g%

7

• Maintain open communications- -!

with the NRC l

Brief the NRC Resident Inspector prior to the outage

• Communications flow through the ResidentInspector

• ResidentInspector access to daily report weekly SGOC meeting

• Follow-up phone call to NRR

• C3 inspection results notification to the region "C' ,,

/

BGE gg XRC Interactions 75 . .

4

• Current tube plugging limit is 800 tubes per SG

• Anticipate reaching / exceeding the tube plugging limit this inspection

• RCS Flow Reduction LAR is  ;

~

needed to support the Unit 1 l

outage  :

NRC0398 N 20

i .,+

3' M

\

Conclusion m

The 1998 SG work scope:

maintains CCXPP's focus on nuclear safety aggressively identifies and repairs degraded tubes  !

provides for inspection scope expansions as necessary to maintain tube integrity NRC0398 N 21

r

1. '

~

l Meetina Summary Distribution: 'Dated: April 10, 1998 LICENSEE: Baltimore Gas and Electric Company < -

FACILITY: Calvert Cliffs Nuclecr Power Plant, Unit No.1

SUMMARY

OF THE MARCH 26,1998, MEETIN 3 REGARDING CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NO.1,1998 STEAM l GENERATOR TUBE INSPECTION E-Mail (wlencl.1) Hard Coov (w/all encis.)

S. Collins /F. Miraglia (SJC1/FJM)

B. Boger (A) (BAB2)

[MNN PUBLIC J. Zwolinski (A) (JAZ) PDI-1 R/F S. Bajwa (SSB1) A. Dromerick S. Little (SLL) OGC T. Martin (SLM3)- ACRS H. Gray J. Muscara S. Coffin cc: Licensee & Service List P. Rush E.Debel B. McCabe (BCM) i i

I i

i "I L r

i i

-