ML20041F568

Slide Presentation Entitled, Pressurized Thermal Shock (PTS) USI A-49 Status Report to Us Nuclear Regulatory Commission,Mar 9,1982

ML20041F568
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Issue date:	03/09/1982
From:	NRC
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ML20041F565	List: ML20041F564 ML20041F566 ML20041F568
References
REF-10CFR9.7, TASK-A-49, TASK-OR NUDOCS 8203170167
Download: ML20041F568 (21)

Text

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PRESSURIZED THEPML SH0CK (PTS).

USI A-49 4

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. STATUS REPORT TO THE U. S. NUCLEAR REGULATORY CO.911SS10H MARCH 9, 1982 f

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SUMARY OF PTS SCHEDULE i

SUMMER OF 1982 INITIAL POSITRON NRC EVALUATION - SAFETY OF CONTINUED CPERATION INITIAL CORRECTIVE ACTIONS REQUIRED 7 0F 8 PLANTS SUBMIT INFORMATION GENERIC RESOLUTION -

SUMMER OF 1983 l

REGULATORY REQUIREMENTS FOR CONTINUED OPERATION ADDITIONAL INFORMATION FROM INDUSTRY INDEPENDENT NRC SPONSORED ANALYSES CONFIRMATORY RESEARcH 3

MATERIAL PROPERTIES INTEGRAL TESTS ON MODEL VESSELS i

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1. 3 INITIAL POSITION SUMMER 1982 USE THE INFORMATIOri AVAILABLE NOW SAFETY OF CONTINUED OPERATION SPECIFY ANY PLANT SPECIFIC CORRECTIVE ACT10flS THAT MUST BE INITIATED BEFORE THE NP,C GENERIC RESULT 10N AND ACCEPTANCE CRITERIA ARE ADOPTED Ei4 Metes:

INCREASE ASSURANCE THAT INDUSTRY ASSUMPTIONS ON OPERATIONS ARE JUSTIFIED LOW LEAKAGE FLUX LOADINGS WARM WATER FOR SAFETY INJECTION I

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1. 4 INITIAL POSITION-SUMMER 1982

- INFORMATION FROM INDUST'RY 7 (OF 8) PLANT RISPONSES (TMI LATE)

GENERIC REPORTS FROM OWNERS GROUPS ADDITIONAL INFORMATION FROM MEETINGS, REQUESTS EPRI PROGRAM (ANNEALING, MIXING)

TECHNICAL ASSISTANCE PNL MULTIDISCIPLINARY TEAM PEER REVIEW PANEL SPECIFIC CODE REVIEWS FOR APPLICABILITY TO PTS NOTRUMP (R) - TO BE REVIEWED AT LANL 4

LOFTRAN (H) - UNDER REVIEW AT ORNL CEFLASH 4 AS (CE) - UNDER REVIEW AT LANL RETRAN02 (CE) - UNDER REVIEW AT ARGONNE CRAFT 2 (B&W) - UNDER REVIEW AT LANL MIXING MODELS - 6 UNDER REVIEW AT LANL i

- FLUENCE BENCHMARKING FOR DOT 3.5 - AT ENL NEAR TERM RESEARCH RESULTS BENDING FRACTURE MECHANICS TESTS

- FRACTURE MECHANICS CALCULATIONS i

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1. 5 INITIAL POSITI0ft T

SUMMARY

OF SUBMITTALS Fit 0M 7 PLANTS SHOW ADEQUATE MARGIN TO PTS VESSEL FAILURE:~

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- END OF LIFE, ALL PLANTS - ALL EVENTS, EXCEPT

- - CALVERT CLIFFS, 21 MORE EFPY FOR MSLB AND SEVERAL E PLANTS IN GENERIC E REPORT 3ASES OF SUBMITTALS:

ANALYSIS OF CERTAIN DESIGN BASIS ACCIDENTS (DBAS)

- ANALYSIS OF CERTAIN ABNORMAL OPERATIONAL OCCURRENCES (A00S)

~ FRACTURE ANALYSES USING PLANT SPECIFIC MATERIAL PROP ERTIES

- ACCEPTANCE CRITERIA VARIED FROM NO INITIATION TO 4 3/4 THICKNESS CRACK

(.!TTLEORNOCORRECTIVEACTIONPROPOSED

- LOW' LEAKAGE FLUX CORE (A FEW PLANTS)

- CONTINUED OPERATOR TRAINING -(SOME f JNTS) g I

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1. 6 RT DT OF LONGITUDINAL WELDS, O F (MARCH, 1982)

N DEC-PEES F PLANT, (NS$$)/ VESSEL FABRICATOR EI.:7 I,1CENSEEs' NRC's NRC's LONSERVA-C0!!SERVA-E,ESTESTIMATE TIVE VALUE TIVE VALUE VALUE FORT CALHOUN, (CE)/CE 209 260 230 MAINE YANKEE, (CE)/CE 170 240~

200 CALVERT CLIFFS, (CE)/CE 205 230 130 H.B. ROBINS 0N, @/CE 183 240 140 HER CIRcUMFERENTIAL WELD 290 290 220 SAN ONOFRE, @ /CE 203 270 160 TURKEY POINT, @ /B&W 211 280 200 OcoNEE, (B&W)/B&W 160 200 160 TMI, (B&W)/B&W l

1. 7

.PRELIMif(ARY FItalf1GS MARCH 1982 RANCHO SECO TRANSIENT W0t4'T CAUSE VESSEL FAILURE IN~

AfiY PLANT TODAY OR NEXT FEW YEARS SOME ACTIONS SEEM PRUDENT THIS SUMMER RESULTS HIGHLY DEPENDENT ON ASSUMPTIONS SEQUENCE AND TIMING OF EVENTS

- EQUIPMEllT FAILURES

- OPERATOR ACTIONS

- DESIGN BASIS ACCIDENTS NOT THE WHOLE STORY MATERI AL PROPERTIES SEEM 3ETTER IN HAND

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Y WIDE VARIATION IN PROPOSED ACCEPTANCE CRITERIA k

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1. 8 GENERIC RESOLUTION SUEER 1983 REGULATORY REQUIREMEtiTS FOR PTS

- CRITERIA FOR CCNTINUED OPERATION

- REQUIRED ANALYSES ACCEPTANCE STANDARDS REQUIRED ACTIONS

- PLAf4( CHANGES

- OPERATIONS t

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MAJOR ISSUES TO BE P.ESOLVED A.

IDENTI ICATION OF PTS EVENT SEQUENCES IMPORTANT TO RISK l.

INITI ATING EVENT (PRECURSOR) i 1.1 ANTICIPATED OPERATING OCCURRENCES (FEEDWATER, STEAM SYSTEM, SAFETY INJECTION...)

1.2 ACCIDENTS (LOCA, S G...)

- SHOULD STRONGLY WEIGH OPERATING EXPERIENCE

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(PLANT RECORDS)

- SHOULD EMPHASIZE LIKELY EVENTS

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- PUMP SEAL LEAKS,, RELIEF VALVE R

AS WELL AS LARGE LOCA

- ATMOSPHERIC DUMP VALVE STICKS OPEN AS,WELL AS fd G t

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1. 10 MAJOR ISSUES 2.

SUBSEGUENT EVENT (S) (EXACERBATING) 2.1 SINGLE FAILURE 2.2 MULTIPLE FAILURES 2.3 OPERATOR ACTIONS CONTINUE TO STRONGLY WEIGH CPERATING EXPERIENCE MANY MULTIPLE EVENT AND MULTIPLE FAILURE SEOUENCES HAVE OCCURRED PROBABILITY OF VESSEL DAMAGE DEPENDS ON EXACT SEQUENCE OF EVENTS TIMING PRESSURE VS TIME LOCAL TEMPERATURE VS TIME NEED TO CONSIDER A VARIETY OF EVENT SEQUENCES NEED TO' CONSIDER OPERATOR (NEXT SLIDE) k

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A.2.3 OPERATOR ACTIONS - PROBABLY THE LARGEST SINGLE FACTOR IN PTS RISK - OPERATOR CAN CREATE, PREVENT, OR MITIGATE PTS EVENTS PROCEDURES ANALYSIS OF CORRECT PATH 6UIDELINES CONTINGENCIES i

EDUCATION AND TRAINING i

$ENSITIVITY OF COURSE OF EVENTS TO DELAYED OR INCORRECT ACTION

- NRC " AUDITS" 0F EXISTING PROCEDURES AND TRAINING AT THE 8 PLANTS i

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1. 12 MAJdR ISSUES B.

ACCEPTANCE CRITERIA INDUSTRY PROPOSALS 1

4 A00s DBAS i

CALVERT CLIFFS AND NO CRACK CRACK FORT CALHOUN (BOTH CE)

INITIATION ARREST I

CE " FEED AND BLEED" NO, INITIATION OF GENERIC REPORT AND CREDIBLE SIZE FLAWS, OR MAINE YANKEE (CE)

IF INITIATE, ARREST AFTER

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LIMITED EXTENSION f

H. B. R0 sins 0N NO INITIATION OF FLAWS TURKEY POINT,

< 1" DEEP OR SAN ONOFRE, AND CRACK ARREST WITHIN 3/4 T i

WESTINGHOUSE GENERIC PTS REPORT (NO CRAC.s7 1" DEEP ASSUMED I

(ALL h)

TO EXIST) f f

OCONEE (B&W)

CRACK ARREST WITHIN 1/4 I i

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1. 13 GENERIC RESOLUTION NRC PROGRAM EVENT TREES (3 " LEAD" PLANTS) i SELECT 10M OF REPRESENTATIVE EVENT SEGUENCES INCLUDING MULTIPLE FAILURES INCLUDING CONSIDERATION OF GOOD AND BAD OPERATOR ACTIONS DEVELOPMENT OF HRC CODES (Pz MODEL, SECONDARY SYSTEM, MIXING) f4LCULAT10N OF PCT) AND I (T, LOCATION) 1 IMPROVEMENT OF NRC FRACTURE MECHANICS CODES CALCULATION OF VESSEL STRESS AND CRACK PROP 0GATION ACCEPTANCE CRITERIA SENSITIVITY STUDIES (UNCERTAINTIES, STATISTICAL DISTRIBUTION) 4 BENEFITS, PRACTICALITY, AND COSTS OF CORRECTIVE ACTIONS REGULATORY REQUIREMENTS FOR GENERIC RESOLUTION OF PTS RECOMMENDED TO NRC SUMMER OF 1983 i

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1. 14 CONFIRMATORY RESEARCH.

PTS METALLURGY AND FRACTURE MECHANICS (FM) RESEARCH ANALYTICAL DEVELOPMENTS ELASTIC PLASTIC FM

- PROBABILISTIC FM PARAPETRIC STUDY FINITE FLAW INITI ATION AND PROPOGATION EFFECTS OF CLADDING EXPERIMENTAL PROGRAM SMALL SCALE CLADDING EFFECTS J

INTERMEDIATE SCALE UNPRESSURIZED EXPERIMENT INTERMEDIATE SCALE PRESSURIZED EXPERIMENT i

IRRADIATION STUDIES l

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1. 15 SLEMARY OF MARCH 9 COMMIS$10N BRIEFING ON PRESSURIZED THERtAL SHOCK (PTS), (USI A-49)

The 60 and 150 day responses to.our August 21, 1981 letters to eight, licensees, together with the Owner's Group responses, have provided:

(1) Better knowledge of plant-specific fluence and materials properties; (2) More detailed plant-specific analyses of certain standard design basis accidents (DBAs) and standard abnomal operational occurrences

-(A00s), including specification of the. event sequences, pressure and tenperature calculations, and fracture mechanics calculations using plant-specific material properties; and (3) Sone additional infomation about plant-specific operational procedures and ope:ator education / training regarding PTS events.

These submittals present each licensee's conclusions that the events analyzed do not represent a significant risk to vessel integrity from PTS or any plant and therefore no substantive corrective actions are needed.

'Je have not coupleted our reviews, but we will probably ultimately agree with at least a considerable portion of the licensees' and Owner's Group conclusions regarding the effects on vessel integrity of PTS events arising f raa standard DBAs and A00s.

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1. 16 However, we continue to believe that the majority of the PTS risk is due to even"ts that involve multiple failures and operator errors, as opposed to the standard DBA and A00 events so far considered in the referenced submittals. We note that all of the FTS precursor events that have occurred have been multiple problem events and not standard DBAs and A00s. A typical way for these multiple problem events to occur is when an overcooling event becones severe enough to cause contraction which drops water level out of the pressurizer. This creates a steam bubble elsewhere in the systeri which causes systen behavior that is less familiar to the operator. The operator is then more likely to make the multiple errors necessary to cause development of a severe PTS event. Of course, this has not in fact occurred. We believe there are many scenarios, some involving the above example, that can lead to PTS events. The large number of such sequences create the potential foe a risk that is not negligibl'e, even though each individual sequence may be calculated to have a very low probability.

The above-described difficulty in defining the events creating PTS risk is currently the major uncertainty in the PTS program. For example, deciding when to allow credit for wam pre-stress is strongly dependent on the detailed sequence of the events analyzed. It is the uncertainty in definition of the course of the event (s) that causes us to question whether wam prestress will be effective in actual events.

1. 17 We do not currently have proper identification and analyses of the multiple probleE events. Our longer range procedures development and PTS programs are designed to provide such infomation by mid-1983, but results will not be available for the June 1982 reassessment. Without such infomation, we do not feel that we can achieve a fim basis for reaching long-tem conclusions about PTS risk for the June 1982 reassessment.

We will continue to urge the industry to provide more complete infomation regarding rultiple problem events while we carplete review of the submitted material leading toward our June 1982 reassessment of the PTS issue to the Conmission. We will also obtain coordinated review assistance of a panel of technical experts from outside the NRC staff in the several relevant fields involved in PTS. Additionally, we will undertake a program to verify that existing operating procedures contain the steps necessary to prevent and/or mitigate PTS events, and to verify that operator education / training programs regarding PTS are acceptably thorough; Our June 1982 reassessment is the near tem objective of our review efforts.

In June, we must answer the question:

"Are corrective actions required at any plant that must be initiated before the longer tem PTS program provides generic resolution and acceptance criteria?"

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If our* staff reviewers, together with our panel of *cutside experts,'

I cannot establish a fim basis to answer the above question ei,ther "yes" i

F or "no," then we would plan to take the conservation approach and recommend to j

the Commission (in June) thos'e corrective actions we believe necessary to e

provide an acceptably conservative safety margin during the interim period l

pending completion of the long tem PTS program.

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t-f Atta heent: Summary of *150 day" Responses Concerning PTS including a I

Summary of Generic Reports Concerning PTS

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SUMMARY

OF "150 DAY" RESPONSES CONCERNING PTS WARM

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' ' ' ' ' ~7CSPON5L PRESTRESSING OPERATOR ACTIONS

1. 1 Atir 10 LEfffRS &

(Hus ytruxm) rtN. CRITENTS CONCLUSIONS LIMITING TRANSIENTS CRITERIA 0F ACCEPT.

CONSIDERED CONSIDERED REMEDIAL ACTIONS HE[ teen 2

1. Irradiation 31 cal, yrs. of Rpt, provided a table of Mt.n. flaw depth for crack Yes, for all Refers to WCAP 10019. 1. Will have low leakage Jan. 25,1982 data vessel life remain. transients considered initiation is greater transients -

Credit is taken for core'in 1982.

2. Wold material ing for all which include following:

than 1.0 inches.

considered.

LSLB. AfW terminated 2. Will keep abreast on HPSI terminated in annealing developments.

(11)

Info.

transients con-1.

Large LOCA

. Crack arrest occurs 10 min.

3. Studying benefits of

3. Basis for sidered.'

2 SDLOCA heating RWST.

keterenced continued 3.

LSLB within 75% of vessel wall

4. Verification analysis tJCAP 10019

~ operation 4 SSLB 5 Rancho Seco by EPRI.

4. Operator actions

5. Hcmedial actions e

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1. Irradiation Reactor vessel in-Ppt. provided a table of Min. flaw depth for Yes,all Cannot determine but Since integrity has been I

Jan. 21, 1982 information tegrity will be transients considered crack initiation is transients WCAP 10019 provides '

demonstrated, no need for l

2. Weld maintained through which include following:

greater than 1.0".

except SSLB following:

action plan.

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material info out destgn life

1. Large LOCA Control ATW

3. Transient

2. SBLOCA Crack arrest occurs l

Relo enced fracture t

3. LSLB within 75% of vessel lirBP lto19 analysis

4. SSLB wall thick.

showing basis

5. Sancho Seco for continued opera tion.

San Unofre

1. Irradiation Reactor vessel Rpt, provjded a table of Hin. flaw depth for Tes, for for LSLB Plan for remedial actions Jcn. 25,198?

effects integrity will be transients considered crack initiation is large.and Terminate HPSI not warranted. Low leakage

2. Material maintained beyond which include following greater.than 1.0".

small LOCAs Terminate AfW to core is in place.

(W) property info design life time.

1.

Large LOCA

only, faulted SG.

3. Basis for 2.

SBLOCA Crack arrest occurs Referenced c*on tinued 3,

LSLB within 75% of vessel for SSLB 11 CAP 10n19 operation.

4.

SSLB wall thick.

Isolate break (PORV) 4; Operation 4.

Rancho Seco Terminate HPSI h

actjons

5. Renedial Actions

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SurNARY OF "150 DAY" RESPONSES CONCERNING PTS

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~1trSPONSE PRESTRESSING OPERATOR ACTIONS Pi ANI TO LLTT[RS &

(fr,ss vifmost)

CEra. CONTENTS CONCLUS10flS LIMITING TRANSIENTS CRITERIA 0F ACCEPT.

CONSIDERED CONSIDERED REMEDIAL ACTIONS it. Calhoun I. Thermal-Ilydro. Integrity will be MSLB most limiting, Over-For MSLB (Low probability) Benefit fm Yes I. Will implement Ja n.18, 1982

Eval, maintained for.

cooling A00- stuck open

- crack arrest.

W.P. not for MSLB - 30 min. to reduced radial (a) SLB lifetime of plant.

dump valve.

Fo-A00 t Single failure considered, reduce HPSI flow.

Icaka<,e fuel (CE)

(b) Overcual-(SBLOCA + L0fW analyzed

- crack arrest, however. it for MSLB - trip RC scheme in Cycle ing (a,ti-inCEN189)

For A00 - No crack was not pumps in 30 seconds 8

cipateil initiation needed. It for A00 trip RCP in

2. Will study other occur-I would have 10 min. Reduce HPSI fuel arrange-been credite< in 90 min.

ment schemes

. rences) if needed

3. Do not plan

?. Fracture Mech, and criteria increase in Analy.for SLB e

met.

ECC water temp.

1. Response to L. Evaluating Dec. IB ltr.

annealing

1. fluence data

5. Program plan will evaluate control systems, proced2res &

potential design

mods, fl. sinc Yankee APP A - response vessel will retain MSLB most limiting No crack initiation.

lienefit fd Yes

1. Low leakage 1/21/82 to 4 150 day integrity through. (cooldown below 300 )

Response references CEN W.P. not for MSLB fuel management 0

questions out design life.

189 Report. Prob. of considered.

Trip RCP 9 30 sec.

for Cycle 7 APP D - response MSLB is very low.

however, it Terminate HPSI 9

2. W111 operate RWT (CE) to RFI of B/21/8<

was not 30 min.

to maintain

.highertempb0not C P C - respunse needed. It to exceed 8 to 1?/10/01 Itr.

would have For A00 been credited Trip RCP 910 min.

3. Will keep

< fu h if heeded Terminate HPSI 9 90 informed. on g

and criteria min.

annealing.

met.

4. Will evaluate control strategy af ter plant specific eval-73 uation is in o

place.

• Don' t address '

selection of events causing biqhest PTS re k.

StfiMARY OF "150 DAY" HESPONSES CONCERNING PTS WARM

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~RESPONSL PRESTRESSING OPERATOR ACTIONS

1. 1 f u f 10 LETIINS &

CONCLllSIONS LlHITING TRANSIENTS CRITERIA 0F ACCEPT.

' CONSIDERED CONSIDERED (In n ytHDnH)

GE,H. CONlENIS REMEp]f u CTIONS

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ralvert - 'l ]Ias respon-No crack initja-15LB most limiting, No crack int tlation f or Benefit im Tes I. Scoping studies on fuel Llitis sive tion for assumed A00 + single failure, A00 W.P. not.

For MSLB management.

Jan. 28, 19u. 2. fluence cal.

plant life for SBLOCA + LOFW analysts Crack arrest for MSLB considered.

Trip RCP 930 sec.

2.00 not plan to increase U<e.p. to

3. Systens SBLOCA + LOFW.'

in CE 189 however, it Reduct HPSI flow 930 RWST temperature.

was not min.

3.No discussion on anneal.

12/lb/ul ltr Analysis Same for stuck needed. It For A00

ing, 1/21/82)

4. fracture open dianp valve would have

• Trip RCP 910 min.

4. Control system changes mechanics (A00) t>een credited Terminate ArW 910 may be considered.

(CL )

For HSLB, satis-if needed an't min. Reduce HPSI factory perfor-mance for 21 addt' l criteria met 9 90 min.

ETPY.

Ownee i

1. Overcooling Vessel failure is SBLOCA + L0fW Crack initiation with Yes, for SBLOCA + L0 g '

l.18 month fuel cycle Ja n. 15. 198, transient not calculated to Overcooling transient arrest within 1/4 T SBLOCA. No Trip RCP. Throttle.

provides decrease in for over-IIPIS 993 min.

leakage flux, analysis. **

result from post-tulated transient, cooling transient

2. Current water temperature Overcooling Transieni sufficient.,

2. SB10CA With minimal down.

Trlp RCP. Isolate 3.loplace annealing not analysis conier mixing, no EfWS #20 min.

required.

(lau)

3. tilxing credit for mixing Throttle llPIS.

bnalysis in hot leg, no 4.No control system changes

4. Vessel wall credit for W.P.-

are necessary.

thermal 16 EFPY. With dnalysjs Credit for W.P.,

Only assuraed above

5. Material

+for SBLOCA-32 actions where properties EfrY. For over-necessary to mitigat<

6. Fluence cooling transient consequences and det ermina tion 25 EIPY (Design achieve acceptable

7. Fr.icture life - approx.

.EFPY.

mech nics 27 EfPY) anJlysis

0. Frequency m-det ermina t too "4

• ). 51B analysis

• • Turbine by-pass systuu

failures, overfill trans ients y~,.

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T St#1HARY OF GENERIC REPORTS CONCERNING PTS EWneral Limiting Criteria of Warm Prestressing Operator Action Potential

n. r.cn la ng Cnntents Conclusions Transients

• Acceptance Considered Considered Remedial Action un t i nyhnu:e ilCAV10019^-

1. Limited transient All plants

• • 1. Small

1. No initiation Benefit of W.P.

Yes-Control AFW l.* Heating RWST to 0

Ihxcad.er 19d1 developnent can continue Steam Line of flows less considered for Trip RCPs as 80 -provide increase "Simariary

' 2. Fluence Calc.

operation a Break than 1 inch SBLOCA and some examples-Report of 3 to 30 EFPY of 1:egmrt on

3. Stress & Fracture number of

2. Rancho Secr deep.

larga LOCA and is not very operation.

1:cac tor Ves.el Hechanics for yrs. (3 for

3. Large (Flaws 71 inch large SL Breaks.

definitive.

?. Limit ATW Integrity tur Transients thelea'st).

Steam Line deep not Genefit was not

3. Control Systems to Uestinghouse

4. Vessel Integrity before Break assumed to considered for mitigate transients Operating Evaluations acceptance

4. Small LOCA exist)cr other transients.

a. RC Press. Relief Plants"

5. Potential Remedial criteria is

5. Large LOCA 2. Crack Arrest System Ar.tions violated. A Occurs within b.' Safety injectica G.' Conclusions (for table pro-75% of wall Control each operating plant) vides no. of "In order of thickness.

c. AFW Control

1. Don't address identi-yrs. for each severity.

4. Core flodifications fication of events plant. Eight

- a. Low leakage loading causing highest PTS plants are

• • Most Limiting

5. Annealing Vessel risk.

S yrs, or less,

a. Is feasible Combustion Iugineering italsF

1. Only addresses SDLOCA Each plant's

1. Only con-

1. tio initiation Benefit of WP was Yes:

None considered "tvoluation with loss of all IW vessel can siders of flows of considered

1. PORVs opened of Pressurized Transient safely with-SDLOCA*LOFW credible size, in 10 min.

Ihuwal Shock ?. Thermal flydro-analysis stand SDLOCA+

or if it'does

'2. ATW reinstated I f tects Due

1. Discussions.on mixing LOFW for initiate.

af ter 30 min, tu Small 1:reat Additional studies design life

2. Arrest af ter IOrAs with are expected to permit without crack limited exten-4 Hater for CE conservatisms

'sion.

I loss of' feed-removal of certain initiation.

hSSS"*

4. Scoping studies indi-thtember 19111 cate range of flPSI -

• (th b is flows must be consider-the Post-ed

• • (Note that Hit " feed &

W. Fluence Calculation HSL break is M,

biced" rpt.-

3. Nterial Properties niost limiting it is nnt a

/. Vessel Integrity but was only Generic PTS Evaluation considered in icpurt.)

1. ' Plant Speci fic the 150 day -

Analysis responses)

N lint Report --prnmised plant-specific. nalyses. fio i sneric report g, omised.

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dc= n two

@h>

of each SECY paper.)

avr.ilabic."

~

ji$iF#dM@ %)MlMWWWMMM*"*"*""~ ^

,m -