ML20209G697

Summary of 990624 Meeting with Util in Rockville,Md to Discuss Plant License Renewal Program.List of Meeting Attendees & Presentation Matls Discussed at Meeting Encl

ML20209G697
Person / Time
Site:	Hatch
Issue date:	07/16/1999
From:	Hatch E NRC (Affiliation Not Assigned)
To:	NRC (Affiliation Not Assigned)
References
NUDOCS 9907190227
Download: ML20209G697 (22)

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yn UNITED STATES 8 ,

,i NUCLEAR REGULATORY COMMISSION

$ WASHINGTON, D.C. SoseHoot July 16,1999 0.,,,,

i LICENSE: Southern Nuclear Operating Company, Inc (SNC)

FACILITY: Edwin 1. Hatch Nuclear Station (Plant Hatch), Units 1 and 2

SUMMARY

OF MEETING BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION (NRC) STAFF AND SNC REPRESENTATIVES TO DISCUSS THE PLANT HATCH LICENSE RENEWAL PROGRAM On June 24,1999, representatives of SNC met with the NRC staff in Rockville, Maryland, to discuss the Plant Hatch license renewal program. The meeting notice provided a list of issues to be discussed at the meeting. A list of meeting attendees is provided as Enclosure 1. A copy of the SNC's presentation material discussed at the meeting is provided as Enclosure 2.

SNC presented and discussed options for Plant Hatch license renewal application to resolve the high energy pipe break postulation as a Time limited Aging Analyses (TLAA), discussed in the draft Standard Review Plan for License Renewal (SRP-LR), Section 4.8-High Energy Pipe Break Postulation. SNC stated that Plant Hatch current licensing basis (CLB) references the 0.1 fatigue cumulative usage factor (CUF) criterion cited in the Branch Technical Position (BTP) l MEB 3-1. Since the fatigue CUF evaluation is a TLAA, a license renewal applicant would have j to identify the approach for disposition of aging effects that meet the criteria for TLAA provided in i the license renewal rule (10 CFR Part 54). Therefore, SNC will be required to address the 0.1 l- CUF screening criterion for ASME Section ill Class I piping as a TLAA by one of the three methods specified in the license renewal rule.

SNC stated that in order to comply with the CLB commitments for the period of extended I operation, it will be required to address any additional high energy pipe break locations where I the CUF exceeds 0.1 during the period of extended operation. SNC suggested that one option would be to monitor locations that are likely to reach the 0.1 CUF criterion during the period of I extended operation and take action in accordance with the CLB when CUF exceeds 0.1. SNC indicated that the preferred option would be to modify the criterion for the postulation of pipe breaks. SNC suggested that the draft SRP-LR, Section 4.8 and BTP MEB 3-1 be revised for postulated location criterion in Class I piping to show CUF less or equal to 0.4 as screening 1 threshold for postulating new break locations. This would likely eliminate the need for SNC to evaluate new pipe break location as a license renewal consideration. SNC also indicated that the ANSI /ANS Standard 58.2 - 1998 has raised the allowable CUF to 0.4. In response to the last option, the staff indicated that increasing the CUF to 0.4 may be difficult to justify in light of the recent information concerning the influence of environmental effects on fatigue life of metal components.

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9907190227 990716 goa Apocn O m g 1 ]\[k /

r July 16,1999 On another subject, Chris Grimes noted that, in a letter dated May 14,1999. ' C. submitted a report illustrating how their renewal process methodology had been applieo r4CS pressure boundary components. Mr. Grimes noted that, while the letter had been sent to the Office of the Secretary requesting a response and completion by specific dates, we understood that SNC only wanted general feedback from the staff since a renewal application for Plant Hatch has not yet been submitted. SNC apologized for the administrative errcr and agreed that formal approval was'not being sought.

original signed by:

Raj K. Anand, Project Manager License Renewal and Standardization Branch Division of Regulatory.lmprovement Programs Office of Nuclear Reactor Regulation Docket Nos. 50-321 and 50-366

Enclosures:

As stated cc w/encis: See next page DISTRIBUTION:

See next page DOCUMENT NAME: G:\ANAND\SUMHATCH1.WPD 74/

[N OFFICE LA j, RLSB:PM BC:EMEB RLSB:BC, NAME E%n" RKAnand R' M Elmbro 2 CIGrimed DATE 07/].$ /99 07/13 /99 07/if/99 07/ @ /99 OFFICIAL RECORD COPY i

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I Southem Nuclear Operating Company Docket Nos.: 50-321,50-366 Edwin 1. Hatch Nuclear Plant Units 1 and 2 cc:

Chairmaa Mr. D.' M. Crowe Appling County Commissioners Manager, Licensing County Courthouse Southem Nuclear Operating Company Inc. Baxley, Georgia 31531 P.O. Box 1295 Birmingham, Alabama 35201-1295 Mr. J. D. Woodard Executive vice President Resident inspector Southem Nuclear Operating Company, Inc.

Plant Hatch .

P. O. Box 1295 11030 Hatch Parkway N. Birmingham, Alabama 35201-1295 Baxley, Georgia 31531 Mr. P. W. Wells Regional Administrator, Region 11 General Manager, Edwin 1. Hatch Nuclear U.S. Nuclear Regulatory Commission Plant Atlanta Federal Center Southem Nuclear Operating Company, Inc.

61 Forsyth Street, SW, Suite 23T85 U.S. Highway 1 North Atlanta, Georgia 30303 P.O. Box 2010 Baxley, Georgia 31515 Mr. Charles H. Badger Office of Planning and Budget Mr. R. D. Barker Room 610 ' Program Manager 270 Washington Street, SW FossS & Nuclear Operations Atlanta, Georgia 30334 Oglethorpe Power Corporation 2100 East Exchange Place Harold Reheis, Director P.O. Box 1349 Department of Natural Resources Tucker, Georgia 30085-1349 205 Butler Street, S.E., Suite 1252 Atlanta, Georgia 30334 Charles A. Patrizia, Esq.

Paul, Hastings, Janofsky & Walker Steven M. Jackson 10th Floor Senior Engineer-Power Supply 1299 Pennsylvania Ave Municipal Electric Authority of Georgia Washington, DC 20004-9500 1470 Riveredge Parkway, N.E.

.' Atlanta, Georgia 30328-4684 Mr. Ray Baker Manager, License Renewal Services Mr. Douglas J. Walter Southem Nuclear Operating Company, Inc.

Nuclear Energy Institute P.O. Box 1295

- 1776 l Street NW . Birmingham, Alabama 35201-1295 Washington, D.C. 20006 DJW@NEl.ORG n -

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DISTRIBUTION: Hard coov Docket File PUBLIC RLSB RF

- N. Dudley, ACRS -T2E26 E. Hylton E-mail- {

R. Zimmerman W. Kane D. Matthews -

~ S. Newberry .

C. Grimes C. Carpenter B. Zaleman J. Strosnider R. Wessman E. Imbro W. Bateman

-J. Calvo l H. Brammer T. Hiltz '

G. Holahan T. Collins

. C. Gratton B. Boger R. Correia R. Latta J. Moore J. Rutberg R. Weisman M. Zobler M. Mayfield S. Bahadur A. Murphy -

D, Martin

- W. McDowell S. Droggitis RLSB Staff R. Emch .

L. Olshan

- C. Ogle, Ril

- J. Munday -

P. Skinner R. Trojanowski C. Julian PMNS OPA J. Fair D. Terao 190005:

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NRC MEETING WITH SOUTHERN NUCLEAR COMPANY (SNC)

LICENSE RENEWAL FOR HATCH UNITS 1 AND 2 10 CFR PART 54 ATTENDANCE LIST JUNE 24,1999 5

NAME ORGANIZATION RAJ ANAND NRC/NRR/ DRIP /RLSB JOHN FAIR NRC/NRR/DE/EMEB ATHEIA WYCHE SERCH LICENSING /BECHTEL i RAY BAKER SOUTHERN NUCLEAR CHARLES PIERCE SOUTHERN NUCLEAR .

BOB NICKELL CONSULTANT, SNOC  !

ROSIN DYLE CONSULTANT, SNC MILLAN STRAKA NUS TUFO  ;

DAVE SOLORIO NRC/NRR/ DRIP /RLSB PT KUO NRC/NRR/ DRIP /RLSB DAVID TERAO NRC/NRR/DE/EMEB GENEIMBRO NRC/NRR/DE/EMEB HAl-BOH WANG NRC/NRR/ DRIP /RLSB H. L. BRAMMER NRC/NRR/DE/EMEB KAMAL MANOLY NRC/NRR/DE/EMEB CHRIS GRIMES NRC/NRR/ DRIP /RLSB WAN LIU NRC/NRR/ DRIP /RLSB JAKE ZIMMERMAN NRC/NRR/ DRIP /RLSB JIM LUEHMAN NRC/NRR/ DRIP /RGEB ,

CHRIS GRATTON NRC/NRR/DSSA/SPLB l JET VORA NRC/RES/DET GOUTAM BAGCHI NRC/NRR/DE

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Attachment 1

SNC/NRC License Renewal Meeting on Selected Thermal Fatigue Topics June 24,1999 1

1 SOUTHERN L COMPANY Energy so Serve nurWorld' l

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l SOUTHERN COMPANY terrg,nsorw Mrw w AGENDA ITEM PRESENTER EXPECTED DURATION

1. Introduction Chuck Pierce 15 min

2. Status Ray Baker 40 min

• Current Ucensing Basis

+ Relation to Ucense Renewal

+ Current Results

3. Suggested Options to Address / Ray Baker 15 min Resolve lasues

4. Technical Discussion of Options All 60 min 1

Attachment 2

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soumEnNA COMPANY

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Plant Hatch Information

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+ Unit 1 and 2 license h: . . .. ; p . '; .

expiration dates are .M ^ - gw -

2014 and 2018.  %..y / ' N * , g< g '

• Application planned for -

Completion by end of "*/' "# . i 1999 and filed after Mj d management approvals in first quarter,2000.

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SOUTHERN COMPANY seen on sme vouserv l Hatch Program - Status l Procese and Appe Descripuon Development Work Acuvity Scoping Complete Compiete gegry g g Complete; Electronic drawin9s under Development development Screening C.rnp6ete Complete; Final approval underway 7LAAs& Complete ident:6cata Complete; EPRI report .

Demotions Jufy 1999 Updates underway.

AMRs Compie,a 3rd Quarter 1999,45% complete, MN3 1999, Draft report 6eveloped and A

f*@pt m she surveys nearing completon; SAMA work underway Applicadon End 1999; Template developed; Prepare #on MA Some sections drafted 2

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l SOUTHERN ComPawy

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introduction of issue

+ High Energy Pipe Break Postulation as a TLAA is discussed in the DRAFT SRP-LR. Section 4.8.

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Meeting Objective l

ACTION i

Present and discuss options to K. solve pipe break TLAA issue in Hatcf?'s application.

1 DESIRED RESULT Obtain NRC feedback and genera'l agreement with SNC's preferred option for addressing Class 1 pipe break location design criteria (0.1 CUF) in the context of license renewal.

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soumnanA COMPANY

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Status - Current Licensing Basis REGULATORY DOCUMENTS l

CURRENT LICENSING BASl3 I

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i soumsawd COMPANY Status - Current Licensing Basis

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• General Design Criterion 4 of10 CFR Part 50, Appendix A

• Section 3.6.2 of NUREG-0800, US Nuclear Regulatory CommissP a Standard Review Plan

• Branch Technical Position (BTP) MEB 31

• Regulatory Guide 1.46 .

CURRENT LICENSING BASl3 i

D Plant Hatch is not an SRP plant, although the Unit 2 FSAR generally follows the format and content of the SRP D However, the Plant Hatch CLB does reference the 0.1 CUF criterion cited in BTP MEB 3-1 and the A. Giambusso letter of December 15,1972 D Specific commitments are contained in:

• Unit 2 FSAR Section 3.6.2.2

• Unit 2 FSAR Supplement 18A.4.2.4

• Unit 1 FSAR Section 5.2

• Unit 1 Appendix N

• Unit 1 Appendix (.J 4

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SOUTHERN comPaw

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Status - Current Licensing Basis BACMGROUND

• General Design Criterion 4 of 10 CFR Part 60. Appendix A Environmernal and dynamic eMeets dealen besee .

Structures, systems. and components important to safety shall be designed to accommodate the effects of and to be cortpatible with the environmental conditions associated with normal operation, maintenance, testing, and postulated accidents, including loss of-coolant accidents.

These structures, systerns, and components shall be appropnetely protected against dynamic effects, induding the effects of rnissiles, pipe whipping, and discharging fluids, that may result from equipment failures and from events and conditons outside the nuclear power evilt. However, dynamic effects associated with postulated pipe ruptures t uclear power units rney be excluded from the design basis when analyses reviewed and approved by the Comfrussion demonstrate that the probability of fluid system piping rupture is extremely low under conditions consistent wm the design basis for the piping.

SOUTHERN coMPA M a,.s, , s.,e.a i Status - Current Licensing Basis i BACKGROUND (cont'd) i I

• Section 3.6.2 of NUREG-0800, US Nuclear Regulatory Commission Starulard Review Plan, provides review criteria for meeting the requirements of General Design Criterion 4 with regard to the determination of postulated rupture locations and the dynamic effects associated with such ruptures. This section also requires information conceming break and crack location criteria and methods of analysis for evaluating the dynamic effects associated with bcesks and cracks in high- and moderate-energy fluid system piping to be .

I provkled in the safety analysis report of the facility. Acceptance criteria l regarding postulated break locations are provided by Branch Technical Position MEB 3-1.

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Status -Current Licensc 3 Basis BACKGROUND (cont'd)

+ Branch Technical Position (BTP) MEB 3-1 provides crteria for determining potential break locations for Class 1 piping in Sections B.1.b.(1) and B.1.c.(1);

D Section B.1.b.(1).(b) addresses postulated pipe breaks between containment isolation valves and containment and is not an issue for Hatch.

D section B.1.c,(1).(c) Except for those locations excluded under Secten B.1.b breaks in Class 1 piping should be postulated atintermediate locations where the cumulative usage factor exceeds 0.1.

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Statua - Current Licensing Basis PACKGROUND (cont'd)

+ Regulatory Guide 1.46 provides an acceptabb basis fbr selecting the desipi locations and onentations ofpostulated breaks in fluid system piping within the reactor containment and Ibr determining the measures that shoukibe taken for i 10straint againstpipe whipping that may result from such breaks. 1 D Code Class 1 Piping - The cumulative usage factor (U) is limited to a value of 0.1.

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sourusaN COMPANY j

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Status - Current Licensing Basis l 1

BACKGROUND (cont'd)

+ Current Licensing Basis . Plant Hatch is not formalty committed to the j requirements contained in the SRP; however, the 0.1 CUF requirement for j

determining postulated pipe break locations is included in the hcansing basis I for both units. The specific Hatch commitments are provided in:

l D Unit 2 Final Safety Analysis Report (FSAR) Sections 3.6.2.2 and 15A.4.2.4 D Unit 1 FSAR Sections 5.2 and Appendices N and Q.

1 sourHaaN COMPANY j E- o as ~ ree w w Status - Current Licensing Basis BACKGROUND (cont'd)

+ Current Licensing Basis -

l D Section 3.8 of the Unit 2 FSAR gives the report on high energy pipe breaks insde l j

containment This secten states that the requirements of pipe break crttens were reviewed post-lEB 79-14 utJlizing the guidance presented in the SRP, and specmcally cites the crneria contairu t in BTP MEB 31.

D Supplement ilA provides the Design Against High-Energy Poe Breaks Outs 4e i the Pnrnary Containtnent This analysis was performed in accordance wtth the criterta provided in the December 16,1972 letter to Georgio Power Corripany frorn A. -

Giambusto, which also contains the 0.1 CUF requirement for pipe break locations.  !

The requirements of the pipe break crtteria were later reviewed in a post-7014 context utilizing the guidance prov6 qed in the SRP. ,

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SOUTHERN COMPANY Status - Current Licensing Basis ""~"~~

BACKGROUND (cont'd)

D The Unit i F8AR in Section 6.2.4.6.1 i D ves the Report on Pipe Breaks inside the Pnmary Containtnent. The tocation critens for postulated pipe breaks used in this analysis originated in ANS-20, later ANSI /ANS 68.2, which apparently, originally speerhed a breakpoint for each location where the CUF was equal to or greater than 0.2. This was later changed to 0.1 in subsequent revisions of the standard and then to 0.4 in the 1968 standard. The 0.1 value corresponds to the values provided in the SRP and in Regulatory Guide 1.46, which was issued in May,1973. The FSAR report, already performed using the 0.2 value, was further evaluated to deterrrune if the more strngent 0.1 value effected the results. It was found that the results of the analysis expressed in the report were not changed by the considerston of the new catena.

D Appendiz N of the Unit 1 FSAR provides the report on hiQh energy pipe breaks outside pnmary containment, in accordance with the crhens provided in the December 15,1972 Gambusso letter.

8 Appendix Q provides the study of recirculation pump missiles, and Regulatory Gum 1.46 la referenced.

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Status - Relation to License Renewal REQUIREMENT DEMONSTRATION 1

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Status - Relation to License Renewal REQUIREMENT

• The license renewal applicant is required to disposition all calculations and evaluations which meet the six criteria for trne-timited aging analyses given in the license renewal rule. The fatigue cumulative usage factor evaluation is a TLAA per the rule defmition, and is specircelly identified in the License Renewal SRP, which states that if a licensee has committed to the CUF criterion for postulating high-energy pipe ruptures in its current licensing basis (CLB), the continued conformance with this commitment for the period of extended operation will be reviewed.

• Thus, SNC will be required to disposition the 0.1 CUF screening criterion for ASME Section 111 Class 1 piping TLAA by one of three methods specified in the License Renewal Rule.

SOUTHERN Status - COMPANY z,wv w Relation to License Renewal (cont'd)

DEMONSTRATION

• Three options are available for this demonstration, corresponding to the three possible disposition methods given in the License Renewal Rule for disposition of TLAAs, with speelfc acceptance criteria provided in SRP-L9 4.8.ll.A:

1) Rule: The analyses remain valid for the period of extended operation; sRP-LR: The existing analyses remain valid because the postulated high-energy pipe break locations where the CUF is projected to exceed 0.1 during the period of extended operation remain the same as those for the current license term in the CLB;

2) Rule: The analyses have been projected to the end of the extended period ofoperation; -

sRP-LR: The existing analyses are revised to include additbnal postulated high-energy pipe break locations where the CUF exceeds 0.1 during the period of extended operation.

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I s.n,ns.r w aw Relation to License Renewal (cont'd) l l

DEMONSTRATION (cont'd)

3) Rule: The effects of aging on the intended function (s) will be adequately l managed for the period of extended operation.

SRP-LR: The effects of aging on the intended function (s) will be adequately managed for the period of extended operation. The effects of pipe break at ,

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locations where the CUF exceeds 0.1 during the period of extended operation and are not the existing postulated break locations could be analyzed and the I l analysis found acceptable in accordance with the plant's CLB.

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l SouTHEaN Status - commy Current Results " ~~

SCOPE OF ISSUE RECIRCULATION SYSTEM AND MAIN STEAM LINE PIPING ALL OTHER CLASS 1 PIPING l

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SOUTHERN Status . comPauY Current Results "'"~'"""

SCOPE OF ISSUE

• By extrapobting CUFs from the current 40 year term to a 60-year term, the only locations which should require action in order to comply with the CLB commtments during the renewal term are those for which the original analysis determined a CUF of greater than 0.067 and less than 0.1. If fatigue cycles increase linearly over time, these locations will be the only ones to reach a CUF of 0.1 during the twenty-year renewal term which have not stready been anayzed.

SOUTHERN COMPANY

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Status - Current Results RECIRCULATION SYSTEM AND MAIN STEAM LINE PIPING

+ Four new locatens on Unit 1 would rneet the 0.1 CUF creerion

+ Three new locations on Unit 2 would meet the 0.1 CUF crRerion ALL OTHER CLASS 1 PIPING

+ 11 new locatens on Una 1 would meet the 0.1 CUF criterion

+ 13 new locations on Unit 2 would meet the 0.1 CUF criterion I1

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Status - Current Results RECIRCULATION SYSTEM AND MAIN STEAM LINE PIPING . UNIT 1 Current Projected Node -Location Value Value 790 - Suction RHR Valve to Anchor 0.070 0.105 130. Main Steam Line B 0.080 0.120 255. Main Steam Line B 0.070 0.105 385 - Main Steam Line B 0.090 0.135 RECIRCULATION SYSTEM AND MAIN STEAM LINE PlPING . UNIT 2 Current Projected Node Location Value Value 612 RHR Retum SS 0.080 0.120 918 RHR Retum SS 0.080 0.120 59 Main Steam Line A 0.090 0.135 SOUTHERN COMPANY

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Status - Current Results REMAINING CLASS 1 PIPING UNIT 1 CUF Between Node Location 0.066 & 0._1 970. Standby Lique Control System 0.0915 10 points . FW piping @ various locatens 0.0677 0.0883 REMAINING CLASS 1 PIPING UNIT 2 CUF Between Node . Location 0.066 & 0.1 140 - RHR Sucten to F008 0.076 15 RPV Head Vent 0.0898 15 RWCU & RPV Drain System 0.093 8 points - FW piping RPV to F077A&B 0.0691 0.0987 5 Primary Steam Cond. Drain Sys. 0.0988 215 Primary Steam Cond. Drain Sys. 0.0801 N

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ser:tHnanA Status - COMPANY su -, w ursw Suggested Options to Resolve !ssues ACTION OPTIONS l

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• Status quo Update the anatyses for 60 years. Design, fabricate, and I

install restraints per MEB 3-1 acesptance criteria.

D This statement assumes that the criteria used in MEB 3-1 to identify the original pipe locat6ns where breaks were to be postulated are intended to be applied to an extension in term of operation separate from any design modifications that would require revision of the existing analyses.

D Evaluation and disposition of the TLAA for License Renewalls assumed to be to the MEB 41 criterion for CUF, B This option would result in physical modificatens to the existing plant.

DResnatysis and appropriate actions in accordance with the CLB where CUF exesads 0.1 would be taken prior to the end of year 40.

souTHEnN Status - "PA*

s.,,,, .'w ur ww Suggested Options to Resolve issues ACTION OPTIOhlS

• Sharpen the pencil Update the analyses using improved methods to remove unnemssary coitervatisms in original analytcal methods in order to reduce the number of new potential break locations, or possibly eliminate all new postulated breair locations.

D This option assunies that use of existing analyticalmethods accepted by NRC would remove unnecessary conservatisms from some or all the new points projected to exceed 0.1 CUF during the renewal term based on extrapolation of the existing CUF values.

D Because it is possbie that not all new points maw be successfully lowered by using improved methods, this option also could lead to physical modifications of the existing plant.

D Reanalysis and appropriate actions in accordance with the CLB where CUF exceeos 0.1 would be taken prior to the end of year 40.

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~,r,.s, w ,m,v Suggested Ootions to Resolve lasues i

ACTION OPTIONS

• Use real data . Using existing approved methods, develop equations for fatigue usage monitoring and use actual operating history to define i

current fatigue usage. Monitor locations to the 0.1 CUF cnterion using real data and take appropriate actions in accordance with the CLB when CUF exceeds 0.1.

D This approach is not currently described in SRP-LR Section 4A D Changes to the CLP. would be needed to explicitty describe how fatigue usage is being rnonitored for the subjec' locations.

D The acceptability of this approach for satisfying the requirements of MEB 3-1 would need to be clearty defined.

D This option is not entirely in direct control of licensee and would require NRC action.

l souTHunNb Status - **"

Suggested Options to Resolve issues e n .s~ v. "mav ACTION OPTIONS

• Revise postulated break location criterion for CUF. Change MEB 3-1 and Draft SRP-LR Section 4.8 CUF acceptance criterion for pos*ulating break locations in Class 1 piping to 0.4.

D This option is not in direct control of the licensee and would require NRC action.

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sourHEnNd Status - COMPANY j

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Suggested Options to Resolve issues PRET ERRED OPTION 1

+ Use a revised number (e.g., CUF <= 0.4) as screening threshold for postulating new break locations 1

J Objective would be to 19eresse the CUF threshold sufficient to eliminate arbitrary Intermediate pipe break evaluations as a  ;

license renewal consideration l l

l souTHEnN Status - COMPANY

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Suggested Options to Resolve lasues PREFERRED OPTION BASES D CUF <= 0.1 represents an extremety low threshold based on:

+ Conservatism in the ASME Code Fatigue Design Process

/ Actual cycles fewer than number assumed (x2)

/ Actualtransients ass severe (x10 x200)

+ Good to excellent margin available against flaw instability

/ 5 BWR piping systems ana'yzed with circumferent6al through-wall flaws assumed with legths of 60 - 300 degrees, and 11 load combinations at the ASME Code design envelope of NB-3650 applied

+ Historical data indicates fatigue pipe ruptures remain unlikely, even with CUF >1 ,

D Eliminating the need to add pipe whip restraints can substantially l improve safety, as noted in the Report of the NRC Piping Review

• ammittee and in the SOCs to the Leak-Before Break Rulemaking due to effects on parameters such as heat loss and thermal expansion i

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souTufRub Status . COMPANY

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Suggested Options to Resolve issues PREFERRED OPTION sASES (cont'd)

D NEl Fatigue Task Force results shows no breaks wth hi0h CUF D The issue is likely to apply to a significant portion of the industry, wth i Hatch being the first plant wth CLB commitments to MEB 3-1. Revising the CUF criterion in MEB 3-1 and Draft SRP-LR Section 4.8 can result in improved efficiency of the license renewal process while maintaining adequate protection against postulated pipe breaks.

1 D ANSl/ANS Standard 58.21988 raised the allowable CUF to 0.4 l

l SOUTHERN comPawy Status -

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Suggested Options to Resolve issues ALTERNATE OPTIONS 1

+ Status quo. required actions would include.

D update analyses to include new break locations D design new pipe whip restraints for new postulated breaks D install new restraints in plant

+ Estimated cost to plarit is $5.27M

+ Sharpen the pencil update calculations using current methods and possibly reduce the number of new postulated break locations

• Estimated cost to plant is $145K to $730K, depending on l degree of success in elirninsting new potential break locations (50%-90%)

+ use real data . rather than project calculations to end of license, montor locations and address when locations approach 0.* CUF based on actual fatque usage data

+ Estimated Cost to plant is $70K plus program costs

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PROPOSED ACTION sNC to request NRC to revise the 0.1 CUF criterion for cletermining locations of postulated high energy pipe breaks to 0.4 for Plant Hatch.

The request would be treated as a curreri term request prior to submitting the license renewal application.

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