ML20154Q987

Summary of 981007 Meeting with NEI & Industry Re Technical & Regulatory Implementation Issues Re NEI 97-06, SG Program Guidelines. List of Attendees & Slides Presented During Meeting,Encl

ML20154Q987
Person / Time
Issue date:	10/20/1998
From:	Tim Reed NRC (Affiliation Not Assigned)
To:	Sullivan E NRC (Affiliation Not Assigned)
References
NUDOCS 9810260128
Download: ML20154Q987 (46)

Text

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t UNITED STATES q

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,y NUCLEAR RE2ULATORY COMMISSION

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o WASHINGTON, D.C. 20066-0001

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October 20, 1998 MEMORANDUM TO:

Edmund Sullivan, Acting Chief Materials and Chemical Engineering Branch Division of Engineering Office of Nuclear Reactor Regulation THRU:

Emmett Murphy, Acting Chief u

Section B Materials and Chemical Engineering Branch i

Division of Engineering Office of Nuclear Reactor Regulation Timothy A. Reed, Senior Project Manager /

FROM:

Materials and Chemical Engineering Branch Jg Division of Engineering Office of Nuclear Reactor Regulation

SUMMARY

OF THE OCTOBER 7,1998 TECHNICAL MEETING WITH i

NUCLEAR INSTITUTE AND INDUSTRY TO DISCUSS ISSUES REGARDING NEl 97-06 On October 7,1998, the NRC staff met with representatives of Nuclear Energy institute (NEI) and industry to discuss technical and regulatory implementation issues regarding NEl 97-06

" Steam Generator Program Guidelines." Meeting attendees are identified in Attachment 1. The slides presented during the meeting are provided as Attachment 2.

Dave Modeen (Nuclear Energy Institute) began the meeting with opening remarks regarding the overall objectives for the NEl 97 06 initiative. He Indicated that industry has made substantial progress in implementing the NEl 97-06 initiative and although there are still technical differences with the staff when comparing NEl 97-06 to draft regulatory guide DG 1074 " Steam Generator Tube Integrity," there is far more agreement than disagreement.

Jack Strosnider (NRC) agreed that substantial progress had been made by industry in the tube integrity area, and he indicated that the staff has put the proposed generic letter on hold while it works with industry to resolve the remaining issues concerning NEl 97-06 with the objective of avoiding issuance of a generic letter on SG tube integrity. It was also stated that currently the staff is stillintending to issue DG 1074 for public comment.

Emmett Murphy (NRC) presented slides (attached) that outlined where the staff believes the NEl 97 06 guidance should be revised to address staff concerns. Steve Long (NRC) presented two slides addressing the consideration of risk within the revised regulatory framework. There was

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2 substantial technical discussions to clarify the differences between the irdustry position in NEl 97-06 (including supporting documents) and the staff's position as contained in DG-1074.

Additionally, the industry provided feedback regarding the difficulties it has experienced in attempting to implement the guidance provided in DG-1074.

Kevin Sweeney (Arizona Public Service) summarized his presentation by indicating that the NEl 97-06 guidance is considered an acceptable baseline for addressing SG tube integrity.

Additionally, NEl 97-06 incorporates the "best experience" to date and the staff should assess the NEl 97-06 approach from an overall programmatic, defense-in-depth viewpoint. The industry believes that from this perspective NEl 97-06 represents a significant improvement in safety and this perspective should be kept in mind when the staff considers the differences that exist on individual technical issues.

The final issue discussed during the meeting was the implementation of NEl 97-06. NEl indicated that NEl 97-06 states that Appendix B criteria apply to the steam generator tube integrity program and that the program is to be documented through plant procedures. NEl also indicated that, to date, the industry has concluded that TS revisions were not worth pursuing.

However, the industry is willing to give additional consideration to the option of TS changes based on the NRC feedback from the meeting.

As a result of the extensive technical discussions, the staff and industry tentatively agreed to have three additional meetings to discuss the following:

1. Feedback from NEl/ industry regarding the staff's suggested revisions to NEl 97-06

2. Difficulties industry has experienced in attempting to implement the operational assessment and condition monitoring methodology described in DG 1074 and satisfy the performance criteria

3. The industry's pilot risk assessment effort and the relation to the risk assessment attributes presented by the staff during the meeting, and a discussion of the threshold when risk needs to be considered.

Attachments: As stated DISTRIBUTION:

PUBLIC/PDR v SJCollins/FJMiraglia EMCB RF OGC SMagruder JStrosnider' 'GClainas Document Name: G:\\ REED \\OCT98MTG. MIN To receive a copy of this document, indicate in the box C= Copy w/o attachment / enclosure E= Copy with attachment / enclosure N = No copy OFFICE DE:EMCB_. ()

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2 substantial technical discussions to clarify the differences between the industry position in NEl 97-06 (including supporting documents) and the staff's position as contained in DG-1074.

Additionally, the industry provided feedback regarding the difficulties it has experienced in attempting to implement the guidance provided in DG-1074.

Kevin Sweeney (Arizona Public Service) summarized his presentation by indicating that the NEl 97-06 guidance is considered an acceptable baseline for addressing SG tube integrity.

Additionally, NEl 97-06 incorporates the "best experience" to date and the staff should assess the NEl 97-06 approach from an overall programmatic, defense-in-depth viewpoint. The industry believes that from this perspective NEl 97 06 represents a significant improvement in safety and this perspective should be kept in mind when the staff considers the differences that exist on individual technical issues.

The finalissue discussed during the meeting was the implementation of NEl 97-06. NEl indicated that NEl 97-06 states that Appendix B criteria apply to the steam generator tube integrity program and that the program is to be documented through plant procedures. NEl also indicated that, to date, the industry has concluded that TS revisions were not worth pursuing.

However, the industry is willing to give additional consideration to the option of TS changes based on the NRC feedback from the meeting.

As a result of the extensive technical discussions, the staff and industry tentatively agreed to have three additional meetings to discuss the following:

i

1. Feedback from NEl/ industry regarding the staff's suggested revisions to NEl 97-06

2. Difficulties industry has experienced in attempting to implement the operational assessment and condition monitoring methodology described in DG-1074 and satisfy the performance criteria

3. The industry's pilot risk assessment effort and the relation to the risk assessment attributes presented by the staff during the meeting, and a discussion of the threshold when risk needs to be considered.

Attachments: As stated

- NEl/EPRl/ INDUSTRY TECHNICAL MEETING ISSUES REGARDING NEl 97-06 OCTOBER 7,1998 LIST OF ATTENDEES NAME ORG/ POSITION

1. Tim Reed NRC/NRR/DE/EMCB

2. Clive Callaway NEl

3. Daniel Pratt ABB

4. Helen Cothron TVA

5. Dave Modeen NEl

6. Forrest Hundley Southem Co.

7. Tom Pitterle Westinghouse

8. - Dan Mayes Duke Power

9. Bill Shack Argonne National Lab 10.Emmett Murphy NRC/NRR/DE/EMCB

11. Steve Long NHC/NRR/DSSA/SPSB

12. Mike Schoppman Florida Power & Light i

13. Rick Mullins Southem Nuclear 14.Ted Sullivan NRC/NRR/DE/EMCB

15. Bob Exner PG&E

16. Richard Pearson Northern States Power 1/. David Geotcheus TVA

18. Greg Kammerdelner Dusquesne Light

19. Donald Streinz ABB

20. Kevin Sweeney Arizona Public Service

21. Mike Neal NUS

22. Anthony Saccavino BGE

23. John Blomgren Comed

24. Cheryl Beardslee NRC/NRR/DE/EMCB 25.Theresa Sutter Bechtel

26. Fred Anderson Tetra Engineering

27. Philip Rush NRC/NRR/DE/EMCB

28. Mati Merilo EPRI

29. Richard Barrett NRC/NRR/DSSA/SPSB

30. Jack Strosnider NRC/NRR/DE J

ATTACHMENT 1

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!1 NRC/NEI TechnicalIssues Meeting

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Outline

Background

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GL Status jl Purpose of this discussion b

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Possible Endgames f

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Technical issues l!

e Risk Considerations t

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Background

Draft GL:

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q existing TS do not ensure tube integrity l:

0 requests licensees submit upgraded TS such as to ensure tube integrity DG-1074, sample TS t

or describe altemative approaches requires response pursuant to 50.54f

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Status / Draft GL i

Staff is now informing the Commission that unless otherwise directed:

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.I staff intends to delay issuance of draft GL while staff works with industry j

to resolve issues relating to NEl 97-06 guidelines I

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staff is proceeding with issuance of DG-1074 and draft DPO Resolution for public comment l

Technical differences still exist between the staff and industry e

including appropriate framework for implementing industry guidelines

.j it is the staff's objective to endorse an industry initiative for ensuring SG tube j

e integrity in lieu of issuing GL as currently drafted.

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1 Purpose of This Discussion To identify regulatory and technical issues conceming NEl 97-06.

e What is the endgame or regulatory structure that we are working to?

,i What technical issues need to be resolved to get there?

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11 Possible Endgames f

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Option 1:

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t Maintain existing TS e

I Utilities commit to implementing industry guidelines endorsed by NRC e

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1 Possible Endgames t:!

Option 2:

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s Replace existing TS with new TS to include:

e performance criteria

!i condition monitoring and operational assessment

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level of conservatism must be addressed i

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repair criteria i

1 approved repair methods other than plugging Utilities commit to implementing industry guidelines endorsed by NRC

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Technical issues

,I Two types:

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i issues concerning NEl 97-06 l-l issues conceming lower-tier NEl/EPRI guidelines (e.g., EPRI SG i

Examination Guidelines) l:

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Possible approach:

e resolve all technical issues in NEl 97-06 leading to revised industry guidelines that the staff can endorse in context of options 1 or 2 i

staff would not formally endorse lower tier guidelines such endorsement may be unnecessary given a performance-based approach in the top tier industry guidelines assuming sufficient box on what it means to satisfy these performance criteria i~;

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i!:t Key Technical issues /NEl 97-06 i'

structural performance criteria e

accident leakage performance critena

'.!i tube inspections l

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condition monitoring / operational assessment e

tube repair limits e

i-tube repair methods e

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t Structural Performance Criteria NEl 97-06:

l Criteria: SG tubes will maintain adequate margin against burst under normal l

e and postulated accident for the operating cycle

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EPRI Steam Generator Tube Integrity Assessment Guidelines (non-

. directive) provides guidance conceming evaluation methods, margin, i

and uncertainty considerations used to determine tube integrity.

i Non-probabilistic methods in the Assessment Guidelines include margins of j

e safety against gross rupture or failure of the tubing consistant with ASME Code.

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,I. I Probabilistic methods in the Assessment Guidelines are based upon e

satisfying specified conditional probability of rupture criteria.

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Structural Performance Criteria NRC Staff Comments:

I The structural integrity criteria should be rev. sed consistant with DG-1074.

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Specifically, a

All tubes shall retain safety factors consistant with stress limit criteria of l

-ASME Code, Section ill, for all service level loadings.

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consistant with design and licensing basis Factor of 3 criterion for nop and 1.4 criterion for accident conditions

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should be specifically spelled out.

to ensure consistancy of interpretation 1

Definition of tube rupture and burst should be revised consistant with DG-

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1074.

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l Structural Performance Criteria NRC Staff Comments (Cont):

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i Altemative criteria may be applied for SGDSM-specific applications if e

reviewed and approved by NRC.

i!!I represents a change to safety factors in licensing basis t

may have potential risk implications Licensees encourage to follow the risk-informed guidance in RG 1.174.-

e Staff will consider risk when reviewing licensee proposals.

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t Probabilistic Structural Performance Criteria NEl 97-06:

Probability of rupture should not exceed-e 5x10-2/yr that 1 tube ruptures during accident

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2.5x10-2/yr that 2-10 tubes rupture during accident 1x10-3/yr that more than 10 tubes rupture during accident

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"/yr" is incorrect for conditional probability criteria e

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i Probabilistic Structural Performance Criteria l

l NRC Staff Comments (Cont):

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Proposed criteria do not allow for:

I unknown defect types known defect types for which burst probabilities have not been quantified t

Proposed criteria represent a change to the safety factors in plant licensing o

basis and thus should be reviewed and approved by NRC staff l

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Appropriate criteria may be plant and SGDSM-specific due to potential risk j

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Accident Leakage Performance Criteria i

NEl 97-06:

Potential p-s.uakage rate during limiting postulated events should not e

exceed:

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t normal makeup capacity of the primary coolant system, and l

offsite radiological doses per 10 CFR 100 guidelines and control room

j doses per GDC-19.

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l.l NRC Staff Comments:

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" Limiting postulated events" is not defined in NEl 97-06. Hoever, NEl 97-06 l

e defines " limiting accident" to be that resulting in the largest differential il pressure accross the SG tubes. This definition does not necessarily result in

l most limiting accident in terms of dose consequences or risk.

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!i Accident Leakage Performance Criteria i!

NRC Staff Comments (Continued):

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" Limiting postulated events" should be revised consistant with DG-1074; j

i.e., postulated design basis accidents other than an SGTR.

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-l Allowing leakage in excess of the LCO operational leakage limits represents

!,j a change to the plant licensing basis with potential risk implications.

1 The accident leakage performance criteria should be revised consistant with

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DG-1074.

I!i.i DG-1074:

i Calculated p-s leakage rate during postulated design basis accidents other

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than SGTR should not exceed the TS LCO operational leakage rate limits (in terms of total leakage from all SGs and leakage from each individual SG).

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Accident Leakage Performance Criteria DG-1074 (Cont):

Altemative criteria may be applied for SGDSM-specific applications if e

q reviewed and approved by the NRC.

.i Altemative accident leakage criteria may be applied to the component of i

e calculated accident leakage associated with implementation of SGDSM programs.

i The balance of the calculated accident leakage rate (i.e., leakage rate for

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e defect types not addressed by SGDSM programs) should not exceed the.

.j LCO operational leakage limits.

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As a maximum, the alternative accident leakage criteria should not exceed e

the value in the licensing basis accident analyses, minus the TS LCO l'

operational leakage limits.

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6 Accident Leakage Performance Criteria DG-1074:

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For plants with flex incorporated in TS, the altemative accident leakage l

e criteria may be determined from the value given in the flex plot as a function of dose equivalent 1131 (minus the LCO operational leakage limits).

l Licensees are encouraged to follow the risk-informed guidance in RG 1.174 e

when submitting proposed altemative criteria for specific SGDSM program (s) or when proposing to extend the applicability of existing approved criteria to additional SGDSM program (s).

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Staff will consider risk when reviewing licensee proposals.

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Tube inspections NEl 97-06:

NEl 97-06 specifies that tube inspections shall be performed in accordance e

with the latest revision of the EPRI SG Examination Guidelines.

sampling using either a prescriptive or performance based approach l

NRC Staff Comments:

The NEl guidelines should specify that the frequency and level of sampling I

e shall follow the EPRI guideline approach for performance based sampling B

rather than for the prescriptive approach.

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The NEl guidelines or EPRI Guidelines should specify guidelines for ll deviating from the EPRI guidelines.

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Tube inspections i

NRC Staff Comments (Cont):

t The NEl and EPRI Guidelines should be revised to address the issues and e

objectives addressed in the DG-1074 guidelines for NDE validation, i.e.

ll quantification of of defect detection and sizing performance of the NDE 1

system (technique and personnel) relative to ground truth expected under i

actual field conditions.

l For example, NEl guidelines could address the definition and objectives k

of NDE validation. The EPRI guidelines could provide guidelines for validating NDE systems.

i Approach being developed by TVA/PG&E to quantify NDE detection and sizing performance for PWSCC at TSPs appears promising.

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Definition of " active degradation mechanism"in EPRI Guidelines, Appendix i

e F, should be revised consistant with definition of " active defect types" given in DG-1074, Definitions.

t This is consistant with the objective of being performance-based.

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.....t EPRI SG Examination Guidelines The NRC staff has not formally reviewed Rev 5 of the guidelines in their I

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entirety.

ij However, DG-1074 incorporates some of these EPRI guidelines, e.g.,

maximum inspection frequencies

'L ii initial inspection sample size l

NDE qualification per EPRI Guidelines Appendices G and H l

constitute a minimumly acceptable approach

!l Formal NRC endorsement of the EPRI SG Examination Guidelines rnay not il e

be necessary given development of a satisfactory performance-based NEl

!l top tier guideline.

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Condition Monitoring and Operational Assessment NEl 97-06:

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Licensees shall perform condition monitoring and operational assessments after each SG inspection.

The EPRI SG Tube Integrity Assessment Guidelines and in-Situ Pressure b

Test Guidelines (non-directive) provide guidance conceming evaluation methods, margins, and uncertainty considerations.

NRC Staff Comments:

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,7 The EPRI sub-tier guidelines should be directive guidelines, not non-i directive.

Note: NRC staff does not have copy of these sub-tier guidelines.

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Condition Monitoring and Operational Assessment i

NRC Staff Comments (Cont):

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i Formal NRC endorsement of these sub-tier guidelines may not be necessary

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given development of a satisfactory top tier NEl guideline. However, the staff would like the opportunity to look at these guidelines prior to reaching a j

position on this point.

The NEl guidelines or the sub-tier guidelines should contain specific o

guidelines for any deviations from these sub-tier guidelines.

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The NEl Guidelines should provide guidance conceming the treatment of e

,l uncertainties and variabilities associated with each of the input parameters i

affecting the outcome of these assessments. The level of conservatism to l:!

be achieved with these assessments should be identified in qualitative or quantitative terms, consistant with staff draft guidance (sample TS, DG-3 1074).

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l Condition Monitoring and Operational Assessment NRC Staff Comments (Cont):

i i-if NEl guidelines specify level of conservatism in qualitative terms, then the e

sub-tier guidelines should quantify level of conservatism to be achieved, i

consistant with DG-1074.

ll NEl guidelines should state that tube integrity assessments may be based 1

e on NDE sizing defect sizing measurements only if if the sizing performance ij of the NDE system has been validated per definition in DG-1074 for the i l t i subject defect type.

NEl guidelines should state that condition monitoring and operational e

assessment is to be performed for each active defect type.

NEl guidelines should address need for corrective actions in event condition e

monitoring indicates performance criteria have been exceeded.

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Tube Repair Limits -

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NEl 97-06:

l Licensees shall establish repair criteria for each active degradation t

e mechanism.

!oU l :iih These repair criteria shall be the existing TS depth-based criteria, a voltage-e based criteria per GL 95-05, or other altemative repair criteria (ARC).

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Development and implementation of ARCS should be performed as part of i

e SGDSM strategies.

! -l I l' Guidelines for developing ARCS are contained in the SG Tube. Integrity Assessment Guidelines.

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For defect mechanisms for which no depth sizing capability exists with NDE,

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l affected tubes should be plugged on. detection and integrity assessed.

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'i Tube Repair Criteria (Cont)

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NRC Staff Comments:

NEl guidelines should state that the tube repair criteria are contained in the e

plant TS.

NEl guidelines should state that " plug on detection" applies when NDE systems are not validated for given defect type.

The TS may be amended to include new ARCS to be implemented as part of

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e SGDSM programs referenced or described in the TS subject to NRC review

j and approval.

l; Implementation of new ARCS may have potential risk implications.

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Licensees are encouraged to to follow the risk-informed guidance in RG 1.174 when submitting proposed ARCS.

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1 The staff will consider risk when reviewing licensee proposals.

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i Tube Repair Methods i i i

NEl 97-06:

.t Licensees shall qualify and implement repair methods in accordance with e

t industry standards.

I The EPRI PWR SG Tube Plug Assessment Document and the EPRI PWR I

e Sleeving Assessment Document provide further guidance.

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l NRC Staff Comments:

L The NEl guidelines should also state that repair methods other than plugging

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shall be in accordance with the plant TS.

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I Additional Comments on NEl 97 06 i

1.

Regulatory Requirements do riot reference the existence of the steam generator inservice inspection requirements currently in the technical specifications, j

2.

According to text in Section 1.4, failures to meet the performance criteria need to be assessed to determine whether they exceed the reporting thresholds of 50.72 and 50.73.

This would not require licensees to notify the NRC of all instances in which performance criteria were violated. However, discussion further on in the document (Section 3.3 and 4) seem to indicate that all such exceedances are reportable. Staff believes such

)

exceedances are reportable.

3.

The only safety function of steam generator tubing as defined in NEl 97-06 is to maintain the integrity of the reactor coolant pressure boundary. DG 1074 identifies additional safety j

functions which should be acknowledged in the NEl guidelines 4.

Section 3.1 states that the inspection component of the degradation assessment shall consider inspection technique probability of detection. Does inspection technique POD address the reduction in POD due to analysts as well?

5.

Plants are required to assess any operational leakage to determine whether it is expected or unexpected. This is not possible during operation because the source of the leakage is unknown.

6.

Definitions in Appendix B should be compared to DG 1074. Consistant terminology is desirable.

7.

12 Month Report Content in Appendix D should include location, measured size, and orientation of each indication found during inservice inspection, and results of any supplemental testing (e.g., in situ pressure tests),

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-l NRC analyses documented in NUREG-1570 have demonstrated o

that, for at least some plants, relaxation of tube integrity requirements to levels proposed.by industry can increase LERF l

beyond accepted levels by increments that are also beyond accepted levels.

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e Attributes ofRisk Assessment to Address CLB' Changes for SG Tube Integrity Assessment should address increments and totals for CDF and LERF Sequences considered should include:

level 1:

e spontaneous rupture ruptures induced by increased AP due to secondary depressurization transients ruptures induced by increased AP due to ATWS events level 2:

ruptures induced by increased AP associated with secondary system depressurizations during core damage sequences ruptures induced by increased' temperatures and AP associated with core damage events The degree of" consideration" should be based on logic, not arbitrary rules. If something is a significant contributor to the total LERF, it should be addressed in the assessment.

l Analyses should be realistic, rather than conservative, but bounding arguments are acceptable.

Physical constraint arguments may be used to limit sequences considered.

Effects of" accident leakage" should be assessed for core damage accidents when tubes are. expected to remain intact but leak more due to relaxed repair criteria.

Sensitivity of results to uncertain parameters should be addressed.

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t NEl Initiative - NEl 97-06 i

r Kevin Sweeney Arizona Public Service l

October 7,1998 l

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NEl Initiative h

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Objectives

. Safe and reliable operation of steam generators

. Cost reductions by minimizing forced shutdowns or midcycle outages Provide elements of comprehensive and strong steam generator degradation management program j

Provide greater consistency in the application of industry guidelines Provide sufficient flexibility to promote new technology Industry response to proposed regulation i

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= Defines requirements of a Steam Generator l

Program

. Should be assessed as " sum of its parts" t

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. Significant actions in excess of Technical l

Specifications Incorporates "Best Experience" to date l

Fostered by a questioning attitude "What is the right thing to do"

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. Commitment through NEl Formal Position j

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+ Recent direction by Commission to assign credit to industry initiatives

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.i Steam Generator Program k

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1 w-i Degradation Assessment i

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2j Inspection

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Tube integrity Assessment t

Maintenance and Repairs

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Primary-to-Secondary Leakage

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Primary and Secondary Side Water Chemistry 1

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Foreign Material Exclusion

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Maintenance of SG Secondary Side l

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j Self Assessment

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Technical Specifications l

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NRC Position i

. Technical Specifications are deficient (Sheron 3/5/97)

+ Too conservative in some areas and not conservative in others l

+ Do not address end-of-cycle tube integrity i

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Industry Position l

. Technical Specifications provide minimum j

requirements j

. Fo_r reliable and cost effective management of steam generators more actions are required

. Tube integrity a commitment in licensing basis

+ GDC 14,19 and 10CFR 100 I

+ Characterized in form of Performance Criteria i

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Actions in excess of Tech Specs

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h NDE - EPRI PWR SG Examination Guidelines a

+ Degradation Assessment Assess not only plant specific but other industry issues Assure NDE techniques are adequate

+ Sampling and Expansion Criteria i

= Requirements well in excess of Technical Specifications NRC endorsed

+ Technique and Analyst Qualification Substantially above ASME and other industry standards l

+ Field implementation - System Performance i

Site Specific Performance Demonstration

= Field analysis feedback l

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i Actions (cont) k i

h! =l Tube Integrity

+ Not explicit in Technical Specifications, but is part of licensing basis and regulation

+ Industry challenge to set standard i

= EPRI SG integrity Assessment Guideline Use of "Best Experience" methodologies Applications for TS(40%), plug-on-detection and ARCS

= Condition Monitoring and Operational Assessment j

Dictates requirements for NDE uncertainty and POD Dictates analysis options

= In Situ Pressure Test Guidelines Supplements NDE inspection Protocol for candidate selection

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Data Analysis b

I Actions (cont) i:

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Operational Leakage - EPRI PSL Guidelines i

m NRC endorsed (DG-1074, RAls) f Provides defense in depth to ensure tube leakage does not i

escalate to a tube rupture Ensures timely response to increasing steam generator tube leakage Shutdown limits lower than current Tech Specs i

+ 150 gpd - shutdown in six (6) hours

. Rate of change action level

= 60 gpd/hr-pmmpt shutdown ~ one (1) hour Plant procedure guidance

+ Alarm response, radiochemical analysis f

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l Actions (cont) q..

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Balance of NEl 97-06

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Maintenance and Repairs

+ Licensee involvement in qualification

+ Plug and sleeve inspections Water Chemistry

+ Procedures to comply with EPRI Primary and Secondary Water l

Chemistry Guidelines Foreign Material Exclusion

+ Procedures to control and monitor foreign objects i

Secondary Side Integrity

+ Assess and monitor secondary side components impacting tube integrity Self Assessment NII w

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Tube Rupture Avoidance k

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= Major objective of industry efforts is reducing the likelihood of SGTR events

. Significant progress to date i

+ No SGTR events since 1993

= SGDSM concept 1991-1992 Review of earlier SGTR events indicates that many would have been avoided through the application of l

the NEl 97-06 steam generator program

. Technical and programmatic elements of NEl 97-06 program are sufficient l

~

SGTR Avoidance - Examples f

C EPRI PWR SG Examination Guidelines

=

McGuire Unit 1 ( Tube not inspected since baseline)

Palo Verde Unit 2 (Critical area definition)

EPRI Primary to Secondary Leak Guidelines

=

North Anna Unit 1 (SGTR basis for 60gpd/hr criteria)

Point Beach Unit 1 (Radiation monitoring equipment)

Surry Unit 1 (150 gpd limit) i McGuire Unit 1 (Equipment and procedural guidance)

=

Secondary Water Chemistry i

Fort Calhoun (Denting)

Palo Verde Unit 2 (Corrosion products, caustic)

Surry Unit 2 (denting)

NAI w

1

i s

t SGTR. Avoidance - Examples j!

?

l Foreign Material Exclusion j

=

Prairie Island (FME - sludge lancing equipment) i Ginna (FOSAR)

=

Tube integrity Analysis Palo Verde Unit 2 (Extreme growth, NDE { POD})

Potentia! (incipient) SGTR Events l

ANO Unit 2 (NDE techniques / procedures / assessment) 1 Maine Yankee (NDE/ Degradation assessment) i Beaver Valley Unit 2 (FME) t Indian Point Unit 3 (Degradation assessment / denting) l NIi w

,