ML20056H205

Summary of 930722-23 Meeting W/Epri & Industry Re EPRI Proposed Steam Generator Degradation Specific Mgt (Sgdsm) Program.List of Meeting Attendees & Handouts Encl

ML20056H205
Person / Time
Issue date:	07/29/1993
From:	Tim Reed Office of Nuclear Reactor Regulation
To:	Bajwa S Office of Nuclear Reactor Regulation
References
NUDOCS 9309080377
Download: ML20056H205 (94)

Text

-

• 4 O

UL y-j., )&

G UNITED STATES

• C NUCLEAR REGULATORY COMMISSION

(

,/

WASHINGTON. D.C. 20%M001 July 29, 1993 MEMORANDUM FOR:

S. Singh Bajwa, Acting Director Project Directorate 11-1 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation FROM:

Timothy A. Reed, Senior Project Manager Project Directorate II-I Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation

SUMMARY

OF MEETING WITH ELECTRIC POWER RESEARCH INSTITUTE ON STEAM GENERATOR DEGRADATION SPECIFIC MANAGEMENT On July 22 and 23,1993, the NRC senior management met with senior management representatives of Electric Power Research Institute (EPRI) and industry to discuss EPRI's proposed steam generator degradation specific management (SGDSM) program. Meeting attendees are listed in Enclosure 1.

The meeting handouts are provided as Enclosure 2.

The meeting was successful in enabling both sides to gain a mutual under-standing of the SGDSM initiative and to understand what each side wants to achieve with degradation specific management.

EPRI is currently scheduled to submit the SGDSM topicals in mid-August for staff review.

The staff is planning to meet with EPRI in mid-September following receipt of the SGDSM topicals.

During the meeting, the staff presented its plans for proceeding with rulemaking to address steam generator inspection in the long-term.

As presently er..'isioned, the SG inspection rule would be supported with a Regulatory Guide that would provide guidance on the inspectin-c each type of SG degradation.

i The staff also received comments from EPRI on NUREG-1477.

Eh ' is i

coordinating utility comments on the NUREG.

EPRI presented what it views to be gravity issues regarding the draft NUREG. The staff was able to provide so additional insight into the thought process b n s sp t f

te Q [J ON: )

y p3 y. y3 ( ei -

4~

9 93090B0377 930729

\\

I C

DR TOPRP EXIEPRI

'4 $iO l']

PDR

(,!lj..jaa c ), u,3 ! )

g

I

?

O ENCLOSURE 1 EPRI STEAM GENERATOR ON DEGRADATION SPECIFIC MANAGEMENT MEETING July 22-23,1993 LIST OF ATTENDEES i

NAME ORG/PjSITION PHONE Chuck Welty EPRI./Mge. S/G 415-855-28?!

John Craig NRC/RES/DE 391-492-3850 Jack Strosnider NRC/NRR 301-50'.-2795 W.T. Russell NRC/NRR 301-504-1274 Jim Partlow NRC/NRR/ADP 301-504-1284 Tim Reed NRC/NRR 301-504-1463 Bill Rasin NUMARC 202-872-1280 Bob Smith RGE 716-724-8074 Jack Woodard SNC 205-868-5086 i

Gene Fitzpatrick AEPSC 614-223-2010 John Jensen AEPSC 614-223-1975 Rick Mullins SNC 205-868-5502 Brad Moore SNC 205-868-5093 Warren Fujimoto PG&E 415-975-0600 Gary Henry EPRI NDE Center 704-547-6188 John F. Smith RGE 716-724-8363 3

Mohamad Behranesh EPRI 415-855-2388 Alex G. Panagus CEC 0 708-663-7380 Sherry Bernhoft WPSC 414-433-1416 Emmett Murphy NRC/NRR/EMCB 301-504-2710 Steve Lacey Duquesne Light /A.V.P 412-393-5202 Greg Kammerdeiner Duquesne Light / Director, Materials 412-393-5677 Richard Pearson NSP/ Consulting Product Engineer 612-388-1121 Dan Mayes Duke / Consulting Engineer 704-382-4211 Kenneth R. Craig Florida Power & Light 407-694-4206 J

Ken Evers WPSC/Mng. Nuc. Plant Support 414-388-2560 Chuck Smoker WPSC/ Supt. Plant Quality Programs 414-388-2560 i

Dave Steininger EPRI/ Technical Advisor 415-855-2019 Tom Pitterle Westinghouse 412-374-5971 4

j

ENCLOSURE 2 Meeting Objectives l

L Mutual Understanding of SGDSM Industry Initiative

- Generic Management Process

- Realistic Repair Criteria / Limits 3

- Enhanced ISI Methods and Procedures

- Industry Role and Relationships

• NRC Position on SGDSM Initiative (Generic Approach)

- Management Review Process

- Mutual Goals and Objectives (Resources, Cost Schedules)

Discuss NUREG 1477 IPC Concerns

- Facilitate Industry Comment

- Management Review Process

=

Update on Industry ISI Guidelines (App G & H) (QDA)

Exchange of Information on Emerging issues

- - - -. ~.

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

Steam Generator i

Degradation Specific Management (SGDSM)

An Industry Initiative David A. Steininger Technical Advisor Steam Generator Reliability Project Office Electric Power Research Institute

^

(EPRI)

July 22,1993

,D NRC+7/22/93*DAS-1 1

HOW IS SGMP-1 STRUCTURED ALLOWING EFFECTIVE INITIATIVES LIKE SGDSM?

SGMP is an EPRI (Utility) funded program directed at solving Generic problems related to steam generator operation.

Managed by EPRI personnel with oversight provided by utility management and technical personnel operating through three standing committees.

Active participation by many foreign utilities operating PWR nuclear plants.

Ad-hoc committees within the SGRP focuses efforts on high priority steam generator issues such as steam generator tube alternate repair criteria (A.RC) and the Inservice Inspections (ISI) Guidelines.

Steam Generator and NDE Vendors have representatives on these committees.

4 NRC.7/22/93.DAS4 2

SINCE FOREIGN UTILITIES HAVE IMPLEMENTED ALTERNATE REPAIR CRITERIA (ARC), ARE THEY REPRESENTED ON INDUSTRY'S AD-HOC ARC COMMITTEE?

G. Airey, Nuclear Electric (England)

G. Bollini, Spanish Utilities 1

J. Engstrom, Swedish State Power Board J-P. Hutin, Electricite de France P. Hernalsteen, Belgium Utilities

,b NRC+7/22/93.DAS-I 3

ARE DOMESTIC UTILITIES WHO ARE NOT MEMBERS OF EPRI REPRESENTED ON THE COMMITTEE?

J. Blomgren, Commonwealth Edison J. Jensen, American Electric Power J. Eastwood, Virginia Power Company To date other non-members have not requested participation.

,A NRC*7/22/93+DAS-1 4

=

WHAT INITIATED THE DEVELOPMENT AND IMPLEMENTATION OF STEAM GENERATOR DEGRADATION SPECIFIC MANAGEMENT (SGDSM)?

Past SGMP/NRC meetings directed at specific ARC and ISI details.

Individual utilities submitting site specific ARC to the NRC with additional utilities considering similar proposals.

SGMP/NRC Annual Review-Meeting in March 1992 discussed i

possible generic licensing implementation and applicable technical aspects of PWSCC and ODSCC ARC.

SGMP offered to initiate a generic effort on SGDSM.

NRC requested a full day meeting to discuss the implementation of the possible generic application of ARC in the licensing arena and certain technical details associated with specific ARC such as PWSCC and ODSCC.

SGMP immediately initiated work on the generic application of ARC i

NRC+7/22/93*DAS-1 5

HAVE FORMAL MEETINGS TAKEN PLACE BETWEEN SGMP AND THE NRC ON SGDSM7 i

Yes December 22, 1992 at USNRC Offices April 15,1993 at USNRC. Offices f

^

4 NRC+7/22/93*DAS-1 6

WHAT IS SGDSM?

SGDSM is a process for-evaluating, monitoring and/or repairing tubes exhibiting distinct, individual tube degradation mechanisms, and includes the following key aspects adequate margin against tube rupture improued inspection procedures and data analysis maintain accident leakage so doses are less than 19CFR199 limits reduced 9110mable leakage during normal operation This-process defines inspection and repair criteria for distinct, individual degradation mechanisms The inspection and repair criteria are determined using generic t

guidelines in the industry developed report, " Steam Generator l

Degradation Specific Management" Utility implementation of the individual inspection and repair criteria follows guidelines contained in the SGDSM report and in reports prepared for each distinct degradation mechanism NRC=7/22/93* DAS-1 7

~

~

WHAT ARE THE SGDSM ELEMENTS ?

INSERVICE INSPECTION Implement industry tube inspection guidelines.

A NDE measured parameter (e.g., crack depth, crack length, eddy current voltage) to reliably assess structural and leakage integrity.

Determination of the NDE measurement uncertainty.

TUBE RUPTURE MARGIN Correlate rupture strength with the NDE measured parameter.

Repair criteria to ensure adequate margins against tube rupture consistent with regulatory requirements.

LEAKAGE LIMITS Correlate the leak rate with-the NDE measured parameter.

Repair criteria to ensure off-site doses less than 10CFR100 limits during postulated faulted loads.

SGDSM Data Base.

SGDSM rupture, leakage and degradation growth data base.

i NRC+7/22/93. DAM 8

. =.

h SGDSM KEY ELEMENTS t

SGDSM KEY ELEMENTS INSERVICE TUBE RUPTURE ACCIDENT SGDSM LEAKAGE INSPECTION MARGIN DATA BASE and DOSE LIMITS ISI Qualifications Rupture Data Leakage Data ISI, Pulled Tubes, etc.

Monitoring of SG Structural Limit Predicted Leakage Rupture, Leakage, condition R.G.1.121 Growth Growth, etc.

Degradation Coordination,

. - Repair Limit NDE Error Measurement -

Growth Predicted Dose

. Reporting NDE Error (Allowable Leakage)

Activity Level

- Spiking Meteorology 1

~

- NRC= 4/15/93+DAS-1 9

l

.u -

-m___~..,m._

v-,~..,em,

--.-<,,-,e_.,

-,,,,-%,..*w e.,-,

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

.,..,,s.m com

,y..,.,,,.,,%.+,,,se_w.,,,_..,,.,-

..m,,,-n,,...,,,,,,,..,,,y,,.

Of' TION 1 - CURRENT DEPTH BASED INSPECTION AND REPAIR Inspection Requirements Current Technical Specifications I

Repair Requirements Current Technical Specifications OPTTON 2 - CURRENT DEPTH BASED INSPECTION AND REPAIR WITH AUGMENieD INSPECIION REOUIREMENTS Inspection Requirements Industry Tube Inspection Guidelines Repair Requirements Current Technical Specifications OI'ITON 3 - DEGRADATION SPECIFIC MANAGEMENT Inspection Requirements Industry Tube Inspection Guidelines Degradation Specific Inspection and Repair Criteria Reports Repair Requirements Current Technical Specifications (for non-degradation specific damage)

Degradation Specific Inspection and Repair Criteria Reports Plant Specfic Calculations I

I s

5

UTILITY SGDSM PROGRAM IMPLEMENTATION AND TECHNICAL SPECIFICATIONS CHANGE EPRI TECH SPEC SGDSM CHANGES REPORT INDUSTRY Y

DEGRADATION TUBE PLANT SPECIFIC SPECIFIC INSPECTION PROGRAM INSPECTION

^

GUIDELINES PLAN AND REPAIR CRITERIA REPORTS Y

PLANT IMPLEMENTATION ACTIVITIES Calculate repair limit' Develop inspection procedures Report results 4

~

NRC+4/15/93+DAS 1 -

.11 -

. ~

. u.

. a...-

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

WHAT EPRI DOCUMENTS REQUIRE NRC REVIEW FOR SGDSM IMPLEMENTATION?

Steam Generator Degradation Specific Management. (to be published)

PWR steam generator tube repair limits:

technical support document for expansion zone PWSCC in roll transitions (Revision 11, EPRI Report.

PWR steam generator tube repair limits:

Technical support document for outside diameter stress corrosion cracking at tube support plates, EPRI Report.

PWR Steam Generator Examination Guidelines:

Revision 3, EPRI

(

l Report, EPRI NP-6201, November 1992.

L 4

This document includes requirements for ISI Performance l

L Demonstration l

l

- NRC+4/15/93+DAS 1 12 l

l_____._______________________..,__

u.

WHAT IS THE CURRENT STATUS OF SGDSM AS A REGULATORY INITIATIVE?

i Lead Plant group identified.

Anticipate Lead Plant submittal to NRC in August.

Possible problem

-- Utility licensing departments have different formai procedures and written formats for interfacing with NRC.

l

(

i i

s f

NRC+ 4/15/93.DAS-1 13

_ - -... _ _ _ _ _ _...- __._ -._ __ _,--..-..._.-....._ ~...,-- --._... _._. _...._ _ _ _-._..-.

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

4

+

L'"l.!.".".i Defect Specific Management SG NDE Activities John Smith 5

Chairman, SGMP-1 TAG NDE Subcommittee Rochester Gas and Electric SGMP-1/ NRC Meeting t

July 22-23,1993 a

.EPRI NDE Center, Charlotte, NC

)

SGMP-1 SGDSM / NRC MTG. 7-93 g

EPRig Presentation Summary ISI Guidelines Sampling Plan f

Performance Demonstration ODGCC Detection Capability Other NDE Activities

\\

)

SGMP-1 SGDSM / NRC MTG. 7-93l l

6 ISI GUIDELINES (PWR Steam Generator Examination Guidelines:

Revision 3, EPRI NP6201, November 1992)

-- Originally developed at the EPRI NDE Center in early 1980s leading to Revision 1 in 1984

-- Revision 2, published in 1988, was developed with considerable input from the utilities, NSSS and ISI vendors and was endorsed by the Senior Representatives of the SGRP Steering Committee

)

~

SGMP-1 SGDSM / NRC MTG. 7-93l

-. ~. -

EPRI / NPD j ISI GUIDELINES CONSISTS OF:

Five Sections (General Topics)

Eight Appendices (Details)

One Supplement (New Information)

J SGMP-1 SGDSM / NRC MTG. 7-93 i

~.

+-r-ew.

<.,,,--s

-w e

--- -~~ =--

--s=-vr ww w.~-m--<-w--eur v=

-= -

-r-'e*-*

-- ~+ - - ~

-v

---~ --- --* --" * --- -

m*

EPRI / NPD j ISI GUIDELINES SECTIONS:

l' 1-- Introduction 2 -- Responsibility 3 -- Guidelines Summary 4 -- SG Examination -- Recommended Practice 5 -- References J

~

SGMP___-1 SGDSM / NRC MTG. 7-93

. ~ - -.

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

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

. ~

4 EPRI / NPD j ISI GUIDELINES APPENDICES:

A-Steam Generator Operating Experience B-Basis for Recommended SG Examination Program C-Steam generator NDE Experience D-Typical Data Analysis Guidelines E-Typical Steam Generator NDE Bid Specification i

F-Definitions G-Qualification of NDE Personnel H-Performance Demonstration for EC Examination

)

~

SGMP 1 SGDSM / NRC MTG. 7-93 i

EfRif/ NPDj ISI GUIDELINES SUPPLEMENT:

I -- Guidelines for Disposition of Bobbin Coil Indications Attributed to ODSCC at Non-Dented and Drilled Tube Support Plates

)

~

SGMP

__-_-1 SGDSM / NRC MTG. 7-931

________,______a

~

ISI Guidelines Sampling Plan Random Sampling

-- To monitor general SG condition 20% minimum sample size per cycle 1

Augmented Sampling SG experience driven Ranges 20% - 100% depending on location J

~

SGMP-1 SGDSM / NRC MTG. 7-93l

-. ~

I E.".LTlI ISI Guidelines Sampling Plan l

3% random sampling per Tech. Spec. minimum requirement is not adequate for all SG's (this sampling rate provides for detection of 1 degraded tube at 90% confidence level should there be 75 degraded tubes in the sieam generator) 20% random sampling is recommended by ISI G/L (this sampling rate provides for detection of 1 degraded tube at 90% confidence level should there be 12 degraded tubes in the steam generator)

)

_ _ _ ___________-9 3 l SGMP 1 SGDSM / NRC MTG. 7

~

L f.tRI[{NPgl w

\\

ISI Guidelines Sampling Plan I

AUGMENTED SAMPLING:

In addition to random sampling l

-- Tubes with previous indications l

SG regions with known or expected degradation I

Sample size is based on risk and probable number of degraded tubes present

-- Technology recommendations are provided for augmented samples, i.e., MRPC, Array coils, etc.

)

~

SGMP-1 SGDSM / NRC MTG. 7-93 l

.-m..

O N

SG ECT Performance Demonstration b

Background

1 The program was developed by an industry group representing utilities, NSSS, and ISI vendors and it is described in two Appendices to the SG ISI Guidelines (EPRI NP-6201 Rev. 3, Nov.1992);

-- Appendix G, Personnel Qualification i

i

-- Appendix H, Performance Demonstration l

l J

j~

SGMP-1 SGDSM / NRC MTG. 7-93 g l

EPRI / NPDl Program Objectives Establish an industry-wide data analyst training and qualification program l

- ensure knowledge #f all current godes of SG degradatiorr,

J f

1 w

- demonstrate [the ability of.the datp analysts to correctly analyze SG eddy currerft data p

A Establish eddy current system performance using a performance demonstration methodology for all damage mechanisms

]

SGMP-1 SGDSM / NRC MTG. 7-93 l a

w

<..<-..--.+. -., *

,.. ~.,

.e.-.

.e.

.e-w-

w.

.,..-m+

-.,,,--s

.r,%e--. - -.. -.

.m -w

.,e, c.-

-+-w.

-,,,e-e..w,

---.,.e-, - -

,+_m.-

,Q Implementation of SG ECT Performance Demonstration

{ Appendices G & H}

-- The industry has developed source materials and implementation protocol through EPRI at the EPRI NDE Center.

-- This capability (training and testing materials ) is i

transportable and intended for program t

implementation by utilities, vendors or other third l

party providers of qualification services.

l

)

SGMP-1 SGDSM / NRC MTG. 7-93l

EPRI / NPDl SG Eddy Current inspection Performance Demonstration 96 t

TRAINING l

$pi DATA MATERIALS da SETS y

7 k$?

INTEGRATION n SAMPLES ) ~ SGMP-1 SGDSM / NRC MTG. 7-93 l --n--.a+.n.an. ~_ _-.----=--,e-. + + -... ,e---,__1-a m, __-__.__,-w ...m w- .----2..-

M Implementation Task Groups Membership J.Benson, NEU G. Boyer, FP&L B. Curtis, ANA H. Houserman, Zetec R. Ingraham, W D. Malinowski, W R. Marlow, CONAM R. Maurer, ABB CE D. Mayes, Du <e S. Redner, NSP - T. Richards, B&W M. Davison, RG&E R. Volmer Zetec i John Smith, RG&E, Chmn. SGRP NDE Subcommittee l Gary Henry, EPRI NDE Center l Steve Brown, EPRI Consultant i Doug Harris, EPRI Consultant l Mohamad Behravesh, EPRI Project Manager ) SGMP-1 SGDSM / NRC MTG. 7-93l -<em,. --e..--.

e-e-m-+w-e-w-ee--w==--w -i.

-s-won -m:ww<-m'e-w.

>e-*>w,--+ee%>.e.w--em.e+-r-. > - rzm-c - 3*e s-m =--4+-cwv-w-

==g,-vme-. e-e- r v es, -r- -ru- .w a n-,,eee w -4,, i. --,---<=-w-c--

APPENDIX G - ANALYST QUALIFICATION User Log-on 'd """* c ' [ \\ Unsecured Text Unsecured Frameviewer ECT Analysis Training Window Window Retest 4 Unsecured Data Secured Text ECT Practice Score > 80%.on 50 y Data Sets Randomly Selected "'S' Questions Yes Y Secured Data ECT Te Data S k Fail Some? =' l Pass all? Training Complete Update Records

• I SGMP-1 SGDSM / NRC MTG. 7-93I E

.. m 1 .m -m

Appendix H Technique dualification WEAR 400/100 DIFF AMP MIX - BOBBIN FRACTION DETECTED & POD @ 90% C/L 13/13 19/19 19/19 13/13 1=' g { 0.9-e 0.8 0.7- ~~ o 0.6 " 0 0.4-i l 0.2- ~ g 0.1 - 0-i 0-19 20-39 40-59 > = 60 % THRU WALL w FRACTION DETECTED POD @ 90% C/L SGMP-1 SGDSM / NRC MTG. 7-93

[ Appendix H Technique Qualification f WEAR 400/100 DIFF AMP MIX-BOBBIN AVB, TSP,V-STRAPS,D-STRAPS 100 90- - DATA -+ -j 80- ++ LEAST SQR'S FIT g 7g. 60 -- ~ + 50-CORR COEF.98 + 40-2 30 -- + ' ' + - RMSE 5.0 20- - - - + - 10- ++; 0' 0 10 20 30 40 50 60 70 80 90 100 TRUTH % THRU WALL ~ SGMP-1 SGDSM / NRC MTG. 7-93

Appendix H T5chnique Qualification ODSCC PRIME /QTR DIFF MIX-BOBBIN FRACTION DETECTED & POD @ 90% C/L l 16/16 21/21 1' ' o 'i i 0 0.9' 4/5 e 0.8- ~~ l ~ 0.7 -- o 0.6-3/6 l 9 ~ ~ 0.5-Q 0.4 - k b 0.3-D ~ p-P, 1 l .2-g E $h 1 1, 0-19 20-39 40-59 > =60 % THRU WALL 7 FRACTION DETECTED M POD @ 90% C/L ~ ~ SGMP-1 S]DSM / NRC MTG. 7-93l

Appendix H Technique Qualification ODSCC PRIME /QTR DIFF MIX-BOBBIN TSP, CREVICE, I I S 100 + + ++ + + 90~ DATA ++ + 8 80- +- N + + LEAST SQR'S FIT + ( +d q 70-D + 50- +/' CORR COEF.23 g 40-g + y 30- + + 20_ RMSE 29.0 + 10 -- -r 1O 20 30 4O 50 6O 7b 8O 90100 0 TRUTH % THRU WALL

E"!.L"El Scope of Training / Qualification For Qualified Data Analyst (QDA) Program provides equivalent of one week of training on text materials and practical signal analysis, plus Practical tests on all currently known SG damage mechanisms that will take an additional week to complete J SGMP-1 SGDSM / NRC MTG. 7-93 l

.M Features of QDA Practical Exam Only App'endix H qualified techniques are used Candidates must analyze tubes end to end Random selection and intermixing of flawed and non-flawed tubes Mix mode degradation in many tubes (i.e. IGA /ODSCC, Thinning, Wear, etc.) -- Typical practical examination involves disposition of >5000 intersections ) l SGMP-1 SGDSM / NRC MTG. 7-93 l

H.".!L"El Grading of QDA Practical Exam DETECTION: 80% POD @ 90% C/L for each damage mechanism

> 40% TW for bobbin coil and MRPC Examples of 80% POD @ 90% C/L

11 out of 11 17 out of 18 23 out of 25 For indications < 40% TW,80% must be detected Overcall rate must remain s 10% ~ SGMP-1 SGDSM / NRC MTG. 7-93l . -.. ~. _ -.. _ _ _, - -. -.-_--.n.-.-,

H."1.Ej Grading of QDA Practical Exam SIZING: Sizing error < 10 RMSE for sizable damage mechanisms, inclusive of both <40 % and > 40 TW l for Thinning, Wear, Pitting, and Impingement ) SGMP-1 SGDSM / NRC MTG. 7-93 l ___ ___ _ _ __a s ~..-.w.. i...%...,.i..%,...m.e, w.., e e .. - -,,..,.n, m -,..u_.

Appendix G Qualification of Nondestructive Examination Personnel for Analysis of Eddy Current Steam Generator Data PLAN FOR A PRELIMINARY IMPLEMENTATION / ASSESSMENT OF THE PERFORMANCE DEMONSTRATION l SGMP-1 SGDSM / NRC MTG.7-93 s

PURPOSE Provide added assurance that the program is reliable and acceptable for the qualification of data analysts (" field test the system"), and to obtain the information needed for further enhancements SPECIFIC OBJECTIVES a Identify and remedy any deficiencies in th.e design or administration of training, data sets, and tests Calculate the difficulty and discriminability of each degraded grading unit, for use in constructing reliable and equivalent tests; check NDD grading. units Establish appropriate time lines for training, practice, and testing ) SGMP-1 SGDSM /.NRC MTG. 7-93 s - m u --w A -..-- = m-m-=%-- a---. - - + - -

---

e---

--,-.e w %+--,ew+- .=--e. e ,iww a ---- - w--++---+ esv.--- .-----w--,-.-4-_.

PRINCIPAL CONSIDERATIONS Conduct performance demonstrations in the assessment in essentially the same manner hs they will be conducted for impleme6tation Increase test scope (by 25%) to allow reiboval of " bad" questions, if any Collect sufficient information to evaluate and refine materials and procedures: Estimates of test reliabilities Estimates of measurement error Grading unit indices Administration problems Time requirements Participant subjective assessments Allow participants to receive credit if the assessment renders the tests acceptable. ~ somes sa h ~

SELECTION OF GRADING UNITS Every grading unit in the data set will be included in the practical tests, and every item in the written test item pool will be included in the written tests Grading units will be assembled into tests of the length that are about 25% longer (minimum 2-3 extra questions per section) than anticipated for actual testing to allow removal of unreliable questions and still be left with tests of adequate lengths. Every grading unit will be examined 10 times (this target value will provide the data needed for statistical analysis) Every grading unit will not be examined by every participating analyst SGMP-1 SGDSM / NRC MTG. 7-93l ~

SELECTION OF ANALYST PARTICIPANTS It s encouraged that data analysts rep, resent the full range oftcapabilities anticipated,in the candidate popul,ation, to attain: yj y i Equivalence to actual administrat.on Accurate

• estimates of test statistics Complete assessment of training, testing 1

g It is encouraged that analysts be relatively evenly distributed throughout this range on the basis of years of experience and qualification level (llA or lil) i SGMP-1 SGDSM / NRC MTG. 7-93 ~

EPRI / NPDl Results of SG ECT Performance Demonstration t i mplementation/ Assessment 11/92-4/93 Vendor Utility Total participants (32) 23 9 Total passed (20) 14 6 Total Failed (11)* 8 3 Passed W&P tests on 1st. attempt (2) 1 1 Passed P test on 1st. attempt (3) 2 1 Passed W test on~1st attempt (21) 15 6 One participant yet to retest W-- Written exam P-- Practical exam SGMP-1 SGDSM / NRC MTG. 7-93 ] r,... ..a+..-. --r .i.-.-,...&+..-m, w--. .6 .u-.. ,..%~.---..,.-~~,----,___.-...-m-----..e _.. -., - _ _. _ _ _ _ _. _ _ _ _, - + -.

n AII

Participants:

Means and 90% Confidence Limits for Detection Performance l l I f.iean 85 IGA /OD9CC 90% Confidence Lir,1it 09 IMPINGEMENT 09 IGMJOI 95 PITTING 95 MRPC 97 WEAR PWSCC THINNING I I I I I I I I I I I O 10 20 30 40 50 60 70 80 90 100 PERCENTAGE OF INDICA TIONS CORRECTLY REPORTED SGMP-1 SGDSM / NRC MTG. 7-93 l

4 Qualifying

Participants:

Means and 90% Confidence Limits for Detection Performance 1 I l Mean 85 IMPINGEMENT E 90% Confidence Limit IGA /ODSCC lGMJOI 93 MRPC PITTING PWSCC WEAR THINNING l I I I I I I I I I I O to 20 30 40 50 60 70 80 90 100 PEllCEN TA GE OF INDICA Tion s ConflECIL Y llEPOf1TED l SGMP-1 SGDSM / NRC MTG. 7-93l ~ mi---a m. m-- n ..._-...~.---.----,.--,,-.-__--.-_-,--,.--~~-,..--m---e -,--_._--...--,-m

a j Utilities & Vendors with Designated QDA Administraton (As of 7-20-93) BG&E RG&E B&W DUKE SCE&G CE-ABB EDF SOUTHERN NUCLEAR CONAM 3 GPU NUCLEAR TOLEDO EDISON WESTINGHOUSE HOUSTON L&P UNION ELECTRIC ZETEC NUSCO VATTENFALL ANA NSP WISCONSIN ELECTRIC ONTARIO HYDRO WOLF CREEK PG&E TECNATOM PSE&G SGMP-1 SGDSM / NRC MTG. 7-93 l m.__ m m__._,mm_. ~ me, --..--....nn..-,----.,---. ,,--,.~,--...-,--,,-------~~,,-.-n.:. .+,,.---.~,-..,-n -..,. ~ .~~-.-,,-,- -,-,,--.-.- r-.-

ODSCC DETECTION FOR PARTICIPANTS WHO PASSED P/D 713 429 110 15 18 0 0.9 + ~ ~~ IS 520 0.8 0.7 ~ ~ Q 0.6 ~ Z O 0.5-b 0.4 ---~ ~~ ~~ ~~ ~ 0.3 '~~ ~ b0.2- ~ - ~ ~~ ~~ ~ ~' ~ k O.1 ~~ ^ ~ 0-F F T <.5 .5 < 1 1 <2 2 <3 3 <4 4 <5 VOLTAGE M FU CTION DETECTED E POD @ 90% C/L } SGMP-1 SGDSM / NRC MTG. 7-93l

Detection Probability independent Two-Party Analysis P(a+b)=P(a)+P(b? - P(a)P(b) 1.0 0.9 0.8 1 r 0.7 0.6 .5 0.6 0.7 0.8 0.9 1.0 e<e> or e<e> saue., saoso, nac 10.7-931

1 EPRI / NPDl TRAINING & QUALIFICATION OF ECT PERSONNEL TRAINING: Vendors' Training Programs for Levels I, ll(llA), & Ill Utilities Training Programs Basic Training Courses at the EPRI NDE Center Review materials as part of the QDA Program QUALIFICATIONS: Vendors in-house programs for Levels I,II(IIA),and lil Industry Performance Demonstration (IDB/ QDAD Utilities' plant-specific Programs J SGMP-1 SGDSM / NRC MTG. 7-93 ~ a .. - - ~ ~ - - _ _ _ - _ _a_~_-- ~-..... .. ~. - - -... .,_,..........._...,.-...._,..._,a._

l l DEPLOYMENT OF UT TECHNOLOGY EPRI development of a UT field-probe for gap measurements in TSP and AVB are under way at NUSON in Europe Efforts are underway to document the performance of Westinghouse, B&W, and NUSON UT systems on known SCC samples this Summer and verify against destructive sectioning in Fall 1993 ? ) ,___-1 SGDSM / NRC MTG. 7-93 SGMP ~

? EPRI / NPD 1 DEPLOYMENT OF FOREIGN TECHNOLOGY Discussions are underway to document the performance of the Belgian (Laborelec) UT system l on EPRI's SCC samples Plans are being drawn to document performance of the British (NNC Ltd ) developed eddy current probe EPC8 on EPRI's SCC samples 1 r J SGMP-1 SGDSM / NRC MTG. 7-93 i ~ . - - -.. - ~,.... - -,, -. - -.. -. - - - -. ,ne. n -,- - --~ ..c ,.. ~

EPRI / NPD l COOPERATIVE R&D EFFORTS WITH THE NRC -- Joint NRC/EPRI effort at PNL on sampling and RR data analysis Discussions are underway to develop, jointly with the NRC Research, a method for thermal enhancement of eddy current signals from SG tubes L Proposal in hand to further develop and test neural network methods for interpretation of eddy current signals -- a continuation of work originally funded by the NRC Research Efforts underway to support an assessment of the l ORNL eddy current probe performance, developed under NRC Research funding j Y SGMP-1 SGDSM / NRC MTG. 7-93 .t l n_ _ + _

SG DEFECT SPECIFIC MANAGEMENT NRC/ INDUSTRY MEETING JULY 22 & 23,1993 1 CHARLOTTE, NC e W.T. RUSSELL, ASSOCIATE DIRECTOR FOR INSPECTION AND TECHNICAL ASSESSEMENT i NRC OFFICE OF NUCLEAR RECTOR REGULATION E i

NRC POSITION ON INDUSTRY DSM INITIATIVE i NRC SUPPORTS THE INDUSTRY DEFECT SPECIFIC MANAGEMENT (DSM) INITIATIVE

• PERCEIVED BENEFITS:

- IMPRO1(ED SCOPE AND METHODS FOR SG INSPECTION - INDUSTRY INCENTIVE TO CONTINUE TO l lMPRO VE INSPECTION METHODS / TECHNOLOGY - DEVELuPMENT OF REPAIR CRITERIA BASED ON THE MOST APPROPRIA TE NDE PARAMETERS (Improves enforceability and eliminates unnecessary conservatism) l I

NRC STRATEGY FOR REVIEW OF DSM/APC PROPOSALS NO PLANT SPECIFIC DSM/APC REVIEWS i t i ALL DSM/APC REVIEWS WILL BE GENERIC REVIEWS e i ) OBJECTIVES: - HIGH QUALITY TECHNICAL REVIEWS' TO ASSURE SAFETY IS MAIN.TAINED/ ENHANCED - MAKE OPTIMAL USE OF NRC AND INDUSTRY i RESOURCES - PROVIDE REGULATORY STABILITY - FOLLOW NRC PROCEDURES AND GUIDELINES FOR IMPLEMENTING NEW OR REWSED CRITERIA

i ] i NRC DEFECT SPECIFIC MANAGEMENT i REVIEW PLAN

• HIGH PRIORITY OBJECTIVES l

- REVIEWINDUSTRY PROPOSALS t - ESTABLISH A REGULATORY FRAMEWORK TO IMWEMENT DSM i - COMPLETE CRGR REVIEW o COMMITTED RESOURCES - DEDICA TED STEERING COMMITTEE AND PROGRAM MANAGER - DEDICATED TECHNICAL STAFF (Materials, Systems, Radiological) - SIGNFICANT TECHNICAL FUNDING ASSISTANCE FOR FY '93 AND FY '94

NRC DEFECT SPECIFIC MANAGEMENT REVIEW PLAN Con't j END PRODUCT: - REGULA TORY FRAMEWORK TO IMPLEMENT DEFECT SPECIFIC MANAGEMENT - APPROVED GENERIC POSITION TO SUPPORT INDUSTRY PROPOSED APCS - NO GUARANTEE THAT APC PROPOSALS WILL BE APPROVED EXACTLY AS SUBMITTED r SCHEDULE: - APPROXIMATELY 24 MONTHS THROUGH CRGR REVIEW - WILL REQUIRE TIMELY INDUSTRY RESPONSE TO RAls ~ - WILL ESTABLISH A SCHEDULE OF NRC/ INDUSTRY MEETINGS TO REVIEW STATUS AND OUTSTANDING ISSUES -l

VOLTAGE BASED PLUGGING CRITERIA BACKGROUND:

• FEBRUARY 1991: FARLEY 1 & 2 SUBMITTAL
• NOVEMBER 1991: FIRST REVISION OF FARLEY WCAP

) l

• DECEMBER 1991: TROJAN IPC REQUEST j
• FEBRUARY-1992: TROJAN IPC GRANTED

-i SECOND REVISION TO I FARLEY WCAP l

• JUNE 1992:

LETTER TO EPRI IDENTIFYING SEVERAL ISSUES TO BE ADDRESSED AS PART OF APC REVIEW l

• NOVEMBER 1992:

TROJAN TUBE LEAK

• JANUARY 1993:

NRC/RES INDEPENDENT EVALUATION

• FEBRUARY 1993:

NRC IPC TASK GROUP FORMED

• JUNE 1993:

DRAFT NUREG 1477 ISSUED FOR COMMENT

i VOLTAGE BASED PLUGGING CRITERIA, Con't 1 NEW INFORMATION:

• THE FRENCH HAVE CONDUCTED MANY HYDROSTATIC TESTS AT PRESSURE DIFFERENTIALS WELL IN EXCESS OF THOSE i

ASSOCIATED WITH POSTULATED DESIGN BASIS I ~ ACCIDENTS i

• THESE TESTS WERE PERFORMED ON STEAM GENERATORS WITH SIGNIFICANT ODSCC AT THE TUBE SUPPORT PLATES AND ROLL TRANSITION l

CRACKS i i

• PRIMARY-TO-SECONDARY LEAKAGE RATES WERE MEASURED DURING THESE TESTS

)

• INFORMATION IS CURRENTLY UNDER REVIEW BY THE NRC STAFF
• INFORMATION SHOULD BE AVAILABLE TO U.S.

INDUSTRY j

VOLTAGE BASED PLUGGING CRITERIA, Con't { N_UREG 1477 l PUBLIC COMMENTS DUE IN MID-AUGUST i - FRENCH WILL PROVIDE DA TA AND COMMENTS i s COMMENTS WILL BE DIVIDED INTO TWO GROUPS - COMMENTS THA T MUST BE ADDRESSED TO ESTABLISH ANINTERIM GENERIC POSITION j - COMMENTS TO BE ADDRESSED AS PART OF \\ l DSM REVIEW i NUREG 1477 WILL BE FINALIZED AND A GENERIC POSITION (GENERIC LETTER) ON INTERIM VOLTAGE BASED APC (1 Volt) TO BE ISSUED BY THE END OF 1993 DRAFT NUREG 1477 PROVIDES GUIDANCE FOR ACCEPTABLE VOLTAGE BASED SUBMITTALS UNTIL THE INTERIM GENERIC POSITION IS ISSUED H

EMERGING STEAM GENERATOR ISSUES FREE SPAN ODSCC - PALO VERDE A - MCGUIRE - FARLEV l CIRCUMFERENTIAL CRACKING - ARKANSAS i ENHANCED INSPECTIONS - PROCEDURES TECHNOLOGY l POTENTIAL / RISK OF MULTIPLE TUBE RUPTURES .l

Emerging Steam Generator Issues EPRI / NRC Meeting 22 July 1993 C. S. Welty, Jr. 1 CSW/NRC 7/22/93-3 1-

~ PERSPECTIVE STEAM GENERATOR MANAGEMENT Mechanism Management Degradation Management Life Extension / Replacement

1. Define Cause

1. Remove on y those tubes

1. Develop Long Range Planning

2. Deveicp Remedies / Damage h M y,

l go rell ty 2. eve m ved Des n 4 Mitigation and/or safety) and no others

a. Materials

a. W/C G/L

a. lSI/NDE

b. Configuration

1) impurity reduction b.kuggin L

it/ Criteria

3. Improve Replacement Activities

2) alternate amines

c. Le) ak Detection -

1 DSM

3) ratio control

b. Sludge Control

d. Leak Location Assess Conquenas @DB)

1) reduce transport 2)Imptove lancfng

3) chemical clerming

c. Stress improvernent 1)in-situ stres1 relief

2) peening

d. T-H Models Performance Measures:

1. Annual Tubes Plugged 1.

Annual Tube Leak Outages 2.' Tube Rupture Events 2. Tube Rupture Events 3. Excess Tube Plugging 4. Regulatory Concern CSW/NRC 7/22/93-1 Pg.4 -....------.,--a-....-..-.-....-~.-~.-...:-...-.--.

1 SUBJECTS: Bundle fouling Steam generator tubing free span cracking SCC / IGA Growth Rate CSW/NRC 7/22/93-3 2

~b r BUNDLE FOULING - RECENT EXAMPLES: Palo Verde - Visual Inspection, bridged deposits between tubes. Certain locations only, defined by T / H conditions R. E. Ginna - Visual Inspection, heavy deposits, upper bundle only. Calloway - Power loss, assumed heavy deposits, no visual inspection. Zion - 1983 tube exam,6 - 8 mil deposits, upper bundle only.- Surry - NRC / Battelle Project, upper bundle only. B&W (OTSG) - Power loss due to level control problems These units are not believed to be unique. i r l CSW/NRC 7/22/93 3 3 -. - - - ~. - -.. - -. - - -. - -... -.. -... -. -. -. -...... -. -. - -..... -.. -.. - -. -..

6 Possible Options to Manage Fouling: When corrosion is not an issue Live with the deposits and eventual power loss Upper bundle shake and lance " pressure pulse" process Full bundle chemical cleaning - process qualified Maintenance / periodic chemical cleaning - no process qualified Top of the bundle - spray nozzles - no process qualified on-line chemical additions before shutdown - no process qualified CSW/NRC 7/22/93-3 4 ~

re f 5 snar t tae h

g d

n e .n t i e o a l u ) i l s e u s C r o s o E r g i r F e r o n m o c i lu e o o o l c a g e u f t a b s g o iv n t n y i ( l d a u e a I mS o k M I f n n r i o o ml y l r o s g r l o y i a t o n f l l r a u i d r g r l s o le a e I e S n c e n r d I e l o n o g s t n i e m a n o t t h h o o p w y n i t d t b s a e O s n n c s n s o n o o o a b l i i e o t s i e i o s t i l i t d r n s b d a n r s e s o o o os h o i n c i t t l c Co c c l t s e e c a o e n n e e h p i i P k f f t e e s a 3 e D D n T 3 I 9 n / i 2 f 2/ e 7 D C RN / W SC lt

Steam generator tubing free span cracking - update Can be defined as any crack not surrounded by a metallic support structure member. Includes sludge pile location, free - span vertical sections above normal sludge pile, u - bend or square bend regions, OD initiated corrosion has been seen in these locations for many years. Sludge vile area: Millstone 2, Calvert Cliffs, Beznau 1 (Switzerland), Doel 4 (Belgium), Nogent 1 (France), many others Vertical free - spans more limited: McGuire 1,2; Palo Verde 2, Farley Upper bundle bend areas more limited: Bruce A (Canada), Palo Verde 2. CSW/NRC 7/22/93-3 6 -~-..,

Postulated Root Causes of Free - Span Cracking May be associated with deposits. Chemical concentration processes under deposits. Increase corrodent levels at the tube surface. Insulating effect, change in thermally induced stresses. Change in local Ecorr, due to incorporation of oxidants at the tube wall. Generally associated with cold worked gouges / areas of deformation. Apparently at least four " defect-specific" free span cracking causes/ mechanisms Sludge pile at TTS Low growth Areas of deformation or gouges Low-to-high growth Heavy deposits such as Palo Verde Low-to-high growth No apparent relation to gouges or significant deposits Low growth CSW/NRC 7/22/93-3 7

Potential Remecies depend on Understanding Causes Thermal hydraulic studies of possible locations for fouling and concentration processes. EPRI developed ATHOS-3 and PORTHOS codes are state -of-the-art, and are being applied to several different steam generator designs. Remedy bundle fouling as listed previously. Modify ISI Guidelines as may be needed for adequate inspection of susceptible locations. Adopt alternate amine secondary water treatment practices to reduce bundle fouling. CSW/NRC 7/22/93-3 8

? i 4 SCC / IGA Growth Rate SCC and IGA growth rates have been defined by field experience and laboratory tests. Laboratory tests have included: pH, Ecorr, caustic concentrations and specific ion effects Steam Generator growth trends have has been consistent with laboratory results. Most Steam Generator growth rates have been on the low side of accelerated laboratory growth rates, i a ) CSW/NRC 7/22/93-3 9

O" Charlotte, NC July 22-23,1993 = Steam generator degradation specific NRC/ industry mana9ement (DSu> -Lead p' of submittals Steam Generator -uanagement oversignt Degradation Specific j [ey,, Management Discussion x J.D. Woodard Southern Nuclear Lead plant submittals Lead Utilities = Lead plant group = American Electric -Generic submittals = Commonwealth Edison -Meet requirements of EPRI report = Duke = Demonstration plant (s) = Duquesne Light = Northern States = Pacific Gas & Electric = Southern Nuclear = Wisconsin Public Service i l i SGDSM Management Resolution of issues l = Lead Plant Group (LPG) provides administrative = Recommend NRC Staff Task Force framework -Lead plant group will meet as necessary to -Executive Steering Committee,3 members address NRC questions

• Duke, Duquesne, Southern Nuclear

-Lead plant group will meet with the Task Force -Interface with SGMP as appropriate -Interface with NRC management - Avoid delays inherent in RAl/ Response = SGMP Ad-Hoc SGDSM Committee provides process j i technical support = NRC Management Oversight Group (3 members) JDW 7/22/93 NRC 07/22/1993 Page 16

l l Demonstration plants Costs = Demonstration plant to develop plant specific = DSM applicable to all PWRs requirements which meet EPRI report = Due to wide app licability, cost recovery from i requirements specific utilities should not be undertaken - ODSCC - Farley -PWSCC Will revisit on completion of ODSCC review How many plants could request Number of plants affected for ARC in the future? degradation types? = Piants with mill annealed alloy 600 steam = ODSCC at TSP (drilled hole tube support plates) generator tubing probably will consider - Approximately 34 plants requesting SGDSM at some point during the life j of the steam generator = ODSCC at TSP (eggerate tube support plates) - Approximately 14 plants = Some plants may be affected by ODSCC, PWSCC, both, or other types of degradation. = PWSCC at roll transitions without shot peening 4 - Approximately 10 plants = PWSCC at ro!! transitions with shot peening - Approximately 13 plants i i h Currently considering SGDSM Schedule = Commanche Peak 1,2 = 12 month review requested = Shearon Harris - Approximately 21/2 years since Farley initial = Sequoyah 1,2 submittal ^ = Watts Barr 1,2 -Basic concepts have not changed since initial = ANO 1, 2 submittalin February 1991 = Waterford i = Calvert C!#fs 1,2 = Palisades 2 = Fort Calhoun JDW 7/22/93 NRC 07/22/1993 Page 7-12

i ^ l l Conclusion i = NRC management approach = Costs "no cost recovery" j = Schedule - 12 month review time a 9 b 4 9 P a 1 i f i i s j t I l l J l 1 JDW 7/22/93 NRC 07/22/1993 Page 13-18

Utility Industry Comments on NUREG 1477 (Draft) EPRl/SGMP-1, NRC Staff Management Meeting SGDSM 22-23 July 1993 EPRI NDE Center Charlotte, NC David A. Steininger Technical Advisor Steam Generator Management Program EPRI DAS/NRC Mfg 7/22-3/93 Pg.1 . - -... _ ~, _. _ _ _,.. -. _

HOW WILL THE UTILITY INDUSTRY FORMALLY COMMENT ON NUREG 1477? Letter to NRC by August 16,1993 under the signature of Robert E. Smith, Chairman of the EPRI/SGMP Executive Committee Letter format - Significant areas of agreement - Imperatives some degree of accommodation required - Suggested improvements Letter written from the perspective of a full alternate repair criteria (ARC) under Steam Generator Degradation Specific Management (SGDSM), a generic approach; not solely motivated by " Interim Criteria" concerns - NUREG references proprietary material not available for review - NUREG's proposed requirements have implications on successful SGDSM and full ARC implementation Presentation of " Imperatives" at this meeting Comments originating from " Interim Criteria" concerns presented by Southern l Nuclear representative at this meeting l DAS/NRC Msg 7/22-3/93 Pg.2

DOES THE UTILITY INDUSTRY INTEND TO FOLLOW UP ON SUBMITTED COMMENTS AND THEIR RESOLUTION?

• Yes

- It is requested that SGMP representatives meet with NRC personnel after letter submittal and before NUREG publication. Reasons - Initiates more effective communication between industry and NRC - Reduces likelihood of establishing unworkable requirements for safe and practical application of SGDSM - Increase likelihood of reaching full alternate repair criteria under SGDSM within a reasonable time frame. DA$NitC Mtg 7722 3 93 l'O ;l ....- - =

WITHIN THE FRAMEWORK OF NUREG 1477, WHAT ARE THE IMPERATIVES REQUIRING ACCOMMODATION FOR SUCCESSFUL SGDSM IMPLEMENTATION? Limited tube pull requirement Recognition of the statistical support for the industry proposed leak rate correlation. Acceptance of industry's POD curve for bobbin coil interrogation of ODSCC at tube support plates. - Credit taken for dual analysis An acceptable probability and confidence value on tube burst is set for MSLB conditions and not for an arbitrary 3 times normal operating pressure, a RG 1.121 requirement. An acceptable probability value is specified for the safety criteria of interest (i.e., radiological dose) only; not on all individual variables that dictate the dose due to steam generator leakage under faulted load conditions. l

• Treatment of radiological consequences of a MSLB with SG leakage include a simple I'3' spike of less than 500.

Voltage based repair criteria is superior to a length / depth based approach. Different eddy current probe sizes can be utilized. DAS/NRC Mtg 7/22-3/93 Pg 4

.~ l WHAT SHOULD BE THE CRITERIA FOR TUBE PULLS UNDER SGDSM AND ITS ASSOCIATED ARC? Plants that haven't pulled tubes establishing degradation morphology may need to do so. - Sufficient NDE data may be available from the plant to establish the degradation mechanism by comparing to NDE signatures available for example, in the industry SGDSM data base. Limited tube pulls across the industry (not on individual plant-by-plant basis) should be performed.to verify degradation's burst and leak correlations maintained in the industry's SGDSM program. - But effort must provide useful, not arbitrary data. DAS/NRC Mtg 7/22493 Pg 5

f WHAT SHOULDN'T BE THE CRITERIA FOR TUBE PULLS? Mandatory morphology verification using pulled tubes. - Morphology of degradation is established by industry wide practice of tube pulls with NDE response fully characterized. True for ODSCC at tube support plates No detectable defect (NDD) verification. a - Unreasonable to request expensive requirement simply to prove a " negative." It requires an infinite amount of data.

• Support for a "no leakage correlation" per NUREG 1477

- Unreasonable to request expensive requirement to support a "no leakage correlation" assumption if established by a published NUREG 1477. DAS/Nf1C Mtg 7/22-3/93 Pg 6 - - -.. - ~

l l IS THERE A LEAKAGE CORRELATION FOR ODSCC AT TUBE SUPPORT PLATES? Yes - Standard statistical tests were used establishing the very low probability of a zero slope linear relationship for ODSCC leakage data. Cogent statistical arguments presented at industry /NRC meeting at USNRC offices,. April 15,1993. Uncertainties associated with the regression line and associated data taken into account under SGDSM. - Similar statistical techniques should be used for other degradation mechanisms under SGDSM and not precluded by NUREG 1477. DAS/NHC Mtg 7/22 3/93 Pg.7 .. _ -.... - ~... ~ _ _,. _ - - - -.. -. _ -..

a WHAT SHOULD BE THE PROBABILITY OF DETECTION (POD) VALUE FOR ODSCC AT TUBE SUPPORT PLATES? It should not be 0.6 per NUREG 1477- - Established by averaging 20-100% through wall crack depth data from an old investigation where specific ISI examination guidelines were not followed. It should be a curve where for example, the POD value vs. voltage is greater than 95% at a 90% confidence for the 1.0 to 3.0 voltage range (the range of most interest). A lower probability value should be allowed for voltages that are not structurally significant. - Credit should be taken for dual analyst requirement for interrogating inspection data. - Bobbin coil data is perfectly adequate; no need for additional verifying techniques. - This information presented at industry /NRC meeting at USNRC offices, April 15,1993. DAS/NHC Mtg 7/22-3'93 Pg 8 ~ -. -

SHOULD A 95%/95% PROBABILITY VALUE BE SPECIFIED FOR TUBE BURST AT THREE (3) TIMES NORMAL OPERATING PRESSURE (NOP) CONDITIONS (RG 1.121 requirement)?

• No

- The factor of three (3) is an engineering safety factor intended to bound uncertainties which have not been quantified. - The 95%/95% probability value or an appropriate value derived with uncertainties accounted should be specified at actual normal operating pressure or main steam-line break conditions. If an engineering safety factor of 3 is mandated, then credit should be allowed for example, for the constraint provided by the tube support plate preventing tube burst under NOP using an appropriate definition of " burst."

• ASME requirement of 1.4 times MSLB pressure conditions as dictated by RG 1.121 should be retained if above is not allowed.

DAS/NRC Mtg 7/22-3/93 Pg.8 ~

SHOULD AN ACCEPTABLE PROBABILITY VALUE BE SPECIFIED FOR THE SAFETY CRITERIA OF INTEREST ONLY (i.e., Radiological Dose due to Steam Generator Leakage Under Faulted Load)? 4 = Yes - An appropriate. probability value should be established for meeting less than 10CFR100 limits. - It is unreasonable to dictate a high probability value (e.g.,95%/95%) on all variables to meet 10% of 10CFR100 limits. Quantification of uncertainties should remove the need for applying engineering safety factors such as one tenth of 10CFR100 limits. - All uncertainties need not be specified at high probability values. DAS/NFIC Mtg 7/22-3/93 Pg.10 .mm m ,m,, ,,,,g ,,, y

SHOULD A REALISTIC TREATMENT OF A MSLB WITH SG 3 LEAKAGE INCLUDE A SIMPLE I SPIKE OF LESS THAN 500?

• Yes

- NRC contractor data indicates that the spike is one to two orders of magnitude less than 500. - NUREG 0844, "NRC Integrated Program for the Resolution of Unresolved Safety Issues A-3, A-4, and A-5 Regarding Steam Generator Tube Integrity," specifies a best. estimate value of 10-20% of the 500 value. DAS/NilC Mtg 7/22393 l'O11 . ~...

IS A VOLTAGE BASED REPAIR CRITERIA FOR ODSCC AT TUBE SUPPORT PLATES SUPERIOR TO A LENGTH / DEPTH BASED C.RITERIA? Yes - The most desirable situation is to define a repair limit that is 1) i reliably enforceable, and 2) provides reasonable assurance that tubes satisfying the limit will continue to maintain structural integrity and limit excessive leakage during faulted load events. A voltage based repair limit for ODSCC at tube supports does this. - NUREG 1477 clearly indicates "the difficulty on reliably modeling complex phenomena like IGA /ODSCC."' i - State-of-the-art NDE technology and that obtainable in the foreseeable future should not and can not provide the necessary, highly accurate inouts to an unreliable mechanistic model of IGA /ODSCC. Such an approach produces more uncertainty than a voltage based criteria. t t' DAS/NFIC Mig 7r22-193 P012 1 _, ~., _......,. -. _ _ ~ _. _ _... _.. _. _ _ _ _ -. -.... _.,, _., _..

e e l 1 SHOULD DIFFERENT EDDY CURRENT PROBE SIZES BE ALLOWED FOR INTERROGATING ODSCC AT TUBE SUPPORT PLATES? L

• Yes

- Smaller size probes needed to interrogate sleeved tubes. - Probe must meet acceptable performance requirements with adequate calibration. - Required performance requirements are dictated by what is allowed under an appropriate propagation of uncertainties to meet limiting criteria. It should not be arbitrarily set at a maximum 5% variation between probes per NUREG 1477. DAS/NRC Mtg 7/22 3/93 Pg 13 . - ~

3 Charlotte, NC July 22-23,1993 = Increased voltage IPC = Approve IPC for longer than one cycle SignifiCant interim = Excessive tube puris required Plugging Criteria (IPC) = use of rotating pancake probe (RPC) - RPC NDD (No Defect Detected) indications ISSUOS = Probe Size = Probe Variability Richard E. Mullins Southern Nuclear increased voltage IPC increase IPC voltage =!ssue = An increased voltage IPC should be approved if -If IPC voltage is kept at 1 volt, tubes which it demonstrates: were " saved" during the last inspection will be -acceptable structuralintegrity plugged because of flaws which are not -acceptable leakage based on an acceptable significant from a structural or leakage rnodel standpoint. l l I Increased dt, ration for IPC Tube pulls =lssue =lssue - Approval of IPC on a cycle basis requires -Pulling nine intersections each outage for an repeated use of resources for an overly IPC is excessive. conservative criteria. = Tube pulls should be based on the specific plant = Approve IPC use till approval of SGDSM. situallon and the need for data. REM 7/22/93 NRC 07/23/1993 Page 1-6 J i

a a 1 Conclusion from Information RPC NDDs Notices =lssue = MRPC probe is acceptable for detecting -Can RPC NDD indications be left in service circumferential or axial cracks, and excluded from leak rate calculation? = To make call solely off RPC is conservative. information Notice 90-49 dated August 6, = 11is reasonable to conclude that if an indication 1990 is NDD by RPC, it will not grow to be structurally - Information Notice 91-67 dated October 21, significant or develop a significant SLB leak rate 1991 within the next cycle. Information Notice 92-80 dated December 7, 1992 Previous Interim Plugging Criteria approvals Previous IPCs Probe Size Currently in use at Farley 1 and 2 =lssue = Precludes removing tubes from service when -Can smaller bobbin probes be used to inspect not a threat to structuralintegrity of tube and not steam generator tubes? a concern for steam line break leakage. = Why use a smaller probe? -Standard 0.720 probe will not pass through sleeved intersections. I t Study Results Probe Variability = 65 intersections at two plants have been =lssue inspected with different s!ze probes. -How tightly can probe to probe voltage i - On 58 intersections, the voltage was variability be con'Jolled? overcalled using the smaller probe = Draft NUREG-1477 recommends con'Jo!!ing -4 of the under calls were on flaws with voltage variability to less than 51 voltages less than i voit - 3 other undercalls were by less than 9% = All flaws were detected with ths smaller probe. REM 7/22/93 NRC 07/23/1993 Page 7-12 1 +

r o e r_ 3 Variability already included in database. Conclusions = Probe voltage function of several factors: = IPC voltage should be increased. - Calibration standard variability = IPC should be approved for use until DSM - Analyst variability approved. -Probe variability = Tube pull requirements should not be an arbitrary = Database includes flaws read with many probes N erse t ns should not be removed from = calibrated on different standards read by various ?ervice or included in the leak rate calculation. a@B' = Smaller probes are acceptable for use. = Probe variability will be investigated; however, a 5% hmit may be too tight. t F i REM 7/22/93 NRC 07/23/1993 Page 13-18

July 29, J993 l i If there are questions regarding the meeting, I can be contacted at 301-504-1463. ~ j ORIGINAL SIGNED BY: l Timothy A. Reed, Senior Project Manager 2 Project Directorate II-l l Division of Reactor Projects - 1/II )

Enclosures:

1. List of Attendees 2. Meeting Handouts j j cc w/ enclosures: See next page 1 i i i DISTRIBUTION: i and 2: i Docket Files j NRC/ Local PDRs l PD 11-1 Rdng. File l T. Reed (2) E. Merschoff, R-II i l

1. Murley/F. Miraglia 12-G-18 l

l J. Partlow 12-G-18 i W. Russell 12-G-18 )

5. Varga i

l G. Lainas S. Bajwa l l P. Anderson i J. Strosnider 7-D-4 J. Craig NLS 007 l E. Jordan MNBB 3701 E. Murphy 7-D-4 i OGC i ACRS (10) L. Plisco, EDO 17-G-21 l l E. Merschoff, R-II l 0FFICE LApf(2GQPE PM}$21:DRPE AD:PD21:DRPE r NAME PDAnb. bb:tmw SSBajwa /k on 07/Qf/93 07/ffT /93 07/ 2 7 /93 DATE m l Document Name: EPRI.MTS .-.}}