h) m d [ zi r. s. iawis

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r2ru:Lu..

OF ;,*,

INI'ERGRANUIAR SI'RESS CDRROSION CRACKING

ON 'IEE

OPERATION OF

GEND GUIE NUCLEAR SIATION UNIT 1

Prepared By: h) M D [ zi *

.

R. S. IAwis A. D. Watkins'

Material Science Engineer Supervisor, Material Science

kE]0+stC. W. Ang]gPrinci 1 Engineer, Operational Analysis

i

jW. F. AdcockPrincipal Mechanical En r

Approved By: / /. Pintoger of Nuclear Plant Engineering

Initial Issue - August 13, 1983

August 16, 1983Revision 1 -

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B308190073 030817PDR ADOCK 05000416P pgg

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CXNITNTS

1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2. IDENTIFICATION OF MATERIALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

3. NONOONPDfEING MATERIAL MITIGNTION ORq USED 'IO MINDiIZE IGSOC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 [

4. PRI%TRVICE AND INSERVICE INsm;nON . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

5. PIANNED FUIURE ACTION FDR MITIGATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

6. WATER CHEMISTRY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

7. IEAK DE'rECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

8. JUSTIFICATION EUR OPERATION .................................... 13

SIM ERY ........................................................ 15..

APPDOIX "A" - INDIVIDUAL WEID IDENTIFICATION

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l. INTPODUC'rIOth

On July 27, 1983, Mississippi Power and Light Capany (MP&L) received aletter frczn the Nuclear Regulatory Cmmission (NBC) with respect toIntergranular Stress Corrosion Cracking (IGSOC) in the Recirculation andResidual Heat Bernoval Piping Systans (reference letter to J.P. McGaughy Jr.- MP&L .frun D. G. Eisenhut - NDC, Docket No. 50-416) . 'Ihe NRC hasconcluded that BWR facilities with non-conforming (Service Sensitive per ,

NUREG-0313, Rev. 1) materials may be susceptible to IGSCC, which may be T

unacceptable ~ for continued safe operation without stress mitigation,augmented inservice inspection, repair of affected pipe, and additionalsurveillance reqairements.

In considering actions relating to the need for the mitigation of stresses,replacement of susceptible piping and augmented inservice irspection, theNBC requested MP&L to subnit the following information:

Identify the materials used and special fabricaticm methods ertployeda.(both in the shcp and in the field) to minimize or mitigate IGSCC inpiping systems which form the reactor coolant pressure boundary. Ebrnon-conforming materials describe the piping systans, the actionstaken or methods utilized (e.g., solution annealing, induction heatstress improvement program, etc.) to mitigate potential IGSOC in thereactor ccolant pressure boundary. If measures are planned to beresponsive to this concern, provide a detailed schedule for theccrrpletion of these actions. (NRC Question #1)

b. Provide a justification for operation with non-conforming materials inthe reactor coolant pressure boundary. (NBC Question #2)

c. Describe what preservice inspections have been accmplished whichwould serve as the baseline for further identification of IGSOC. (NRC

Question #3)

d. Describe what programs are to be implarented in water chenistrycontrol to minimize or mitigate IGSOC. (NBC Question f4)

The purpose of this report is to provide a status and surrmary of the GrandGulf Nuclear Station - Unit 1 (GGNS) reactor coolant pressure boundary withrespect to intergranular stress corrosion cracking and to provide aresponse to each of the above questions. 'Ihe reactor coolant pressureboundary is defined in accordance with the guidelines set forth in the Codeof Federal Regulations,10CFR 50.2(v) . In addition, the scope of thissturmary will be limited to circunfrential butt welds whose diameter exceedsor equal 2 inches.

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2. MATERIAL IDD7TIFICATION - (NIC CUESTION f1)

'Ihe GGNS - Unit I reactor coolant pressure boundary consists of thefollowing material, as stated in the Final Safety Analysis Report (PSAR) .Material variations and/or additions between this data and the Final Safety

Analysis Report (FSAR) are indicated by a revisicri bar...

'IA. RBCIICUIATION SYSTm

[ [ [ [ SPECIFICATION ]

[ omrotafr [ MIN [ MATERIAL [ (ASME/AS E) 1

[ [ [ [ ][ Pipe [ Welded [ Stainless [ SA 358, Gr. 304, 1

[ [ [ [ C1. I l[ [ [ [ ][ Pipe [ Seamless [ Stainless [ SA-376, TP 304 1

[ [ [ [ ][ Elbow [ Fitting [ Stainless [ SA-403, Gr. WP304W cr ][ [ Plate [ Stainless [ SA-240 Gr. WP304IN 1

[ [ [ [ ][ Nozzle [ Fitting [ Stainless [ SA-403, Gr. WP 304 ][ [ Plate [ Stainless [ SA-240 l[ [ [ [ ][ Flange [ Forging [ Stainless [ SA-182, Gr. F316 )[ [ [ [ ][ Lug [ Plate [ Stainless [ SA-240, Gr. 304 1

[ [ [ [ ][ Bolt [ Bolting [ Im Alloy [ SA-193, Gr. B7 1

[ [ [ [ ][ Nut [ Bolting [ Im Alloy [ SA-194, Gr. 7, 2H ][ [ [ [ ][ Safe End [ Forging [ Stainless [ SA-182, Gr. 316L ] |[ [ [ [ ][ [ [ [ ]

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B. MIN SITAM PIPING

[ [ I I SPECIFICATION }

[ a n par e rr [ mfN [ MTERIAL [ (ASME/ASIM) }[ [ I 1[ _

[ Fitting [ Carbon Steel [ SA-420, Gr. WPBW, )[ Elbow[ . [ [ [ Code Case 1571 )[ [ [ [ ]~

[ Pipe , [ Welded [ Carbon Steel [ SA-155, Gr. KCF70, 1;

[ -[ [ [ Cl. 1 1''

[ [ [ [ A516, Gr. 70 1

[ [ [ [ }[ Pipe [ Seamless [ Carbon Steel [ SA-106, Gr. B ][ [ [ [ ]

[ Elbow [ Fitting [ Carbcn Steel [ SA-234 Gr. WPBW ][ [ Plate [ Carbcn Steel [ A516 Gr. 70 )

3

[ [ [ [ Code Case 1571 ][ [ [ [ ][ Flange [ Forging [ Carbon Steel [ SA-105 )[ [ [ [ ][ Nozzles [ Forging [ Carbcn Steel [ SA-105, Code Case ][ [ [ [ 1519 )[ [ Forging [ Carbon Steel [ SA-181, Gr. II ][ [ [ [ ][ Ings [ Plate [ Carton Steel [ SA-516, Gr. 70 }[ [ [ [ ][ Nozzles [ Forging [ Carbon Steel [ SA-350, Gr. LF2 )[ [ [ [ ][ Safe End [ Forging [ Carbon Steel [ SA-508, Cl. 1 ][ [ [ [ ][ [ [ [ ]

3

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C. FEEDATER (EW), IDW PRESSURE ODE SPRAY (LPCS), HIW PESSURE COESPRAY (HPCS), RDCIOR CDRE ISOIATIN CDOLING (RCIC)

[ [ [ [ SPIIIFICATIN ][ cmPONENP [ FDfH [ MATERIAL [ (ASME/ASM) 1

[ [ [ [ ][ Pipe. [ Seamless [ Carbon Steel [ SA-106 Gr. C ][ [ [ [ } ,

[ Pipei ,[ Seamless [ Carbon Steel [ SA-106 Gr. B 1'

[ [ [ [ ][ Fitting [ Welded [ Carbon Steel [ SA-234 Gr. WPCW l[ [ [ [ }

[ Fitting [ Seamless [ Carbon Steel [ SA-234 Gr. WPC 1

[ [ [ [ ][ Fitting [ Welded [ Carbon Steel [ SA-234 Gr. WPB ][ [ [ [ ][ Fitting [ Ibrging [ Carbon Steel [ SA-105 1

[ [ [ [ ][ Safe Ends [ Forging [ Carbon Steel [ SA-508 Cl. 1 )

][ [ [ [ t

[ [ [ [ ].t

NOTE: Safe Ends Apply to FW, LPCS, and HPCS ONLY.

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D. REACIOR WATER CLEAN UP (IHCU), RESIDtAL HEAT REMNAL (RHR)

[ [ [ [ SPECIFICATION ][ CCMPONDTP [ FORM [ MATERIAL [ (ASME/AS'IM) )[ [ [ [ ][ Pipe . [ Seamless [ Stainless [ SA-132 TP304L 1

[ [ [ [ ]'

[ Pipe,, [ Seamless [ Carbon [ SA-106 Gr. C 1'[ -[ [ [ ]'

[ Pipe [ Seamless [ Carbon [ SA-106 Gr. B lI [ [ [ ][ Fitting [ Seamless [ Stainless [ SA-403 WP304L 1

I [ [ [ ][ Fitting [ Forging [ Stainless [ SA-182 F304L 1

I [ [ [ l[ Fitting [ Welded [ Carbon [ SA-234 Gr. WPCW l[ [ [ [ ][ Fittings [ Seamless [ Carbon [ SA-234-Gr. WPC 1

I [ [ [ ][ Fittings [ Seamless [ Carbon [ SA-234 Gr. WPB ][ [ [ [ ][ Fittings [ Forging [ Carbon [ SA-105 )

[ [ [ [ ][ Safe Ends [ Forging [ Carbon Steel [ SA-508 C1. I 1

[ I [ [ ][ [ [ [ ]

NorE: Stainless Steel portions are those small porticos that prwiGconnection with the Recirculating Water System.

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3. NUN 00NPORtING 1%TERIAL MITIGATION OR M!' DEES UTILIZED BY GGNS 'IO MINIMIZEIGSOC - (NIC QUESTION 91)

A. Recirculating Water System,

1. Mitigation practices employed by the manufacturer for the weldingof spool assemblies consisted of:*

.

/ (a) Solution annealing / quenching after welding.

(b) Application of weld inlay (corrosion resistant weld buildup) on weld and preparations using Type 308L filler'

materials.'

,

i (c) See Itan 2(c) (Regulatory Guide,1.44) for requirementsinposed on the manufacturer by General Electric.'

NOTE: See Appendix "A" of this Report for individual weldmitigation techniques.

2. During field fabrication the practices employed to mitigate or'

minimize IGSOC were:

(a) 'Ihe original Reactor Pressure Vessel (RPV) Safe Ends wereI m oved and replaced with SA-182 F 316L with inconel andER308L butter applied to the weld end preparations.

(b) Weld inlays were applied to the sweepolets on the ringheader and RWCU nozzles located on the pe p suction spools.'Ihe filler material used was Type 308L with ferritemeasurements averaging 8.05 per cent miniman. Measurementswere taken on deposited weld metal. (See Appendix A forspecific weld location).'

(c) Adherence to the " Final Safety Analysis Report" Appendix 3A,Regulatory Guides 1.31 Rev. I " Control of Stainless SteelWelding" and 1.44 " Control of the use of SensitizedStainless Steel". In empliance with the positions taken tothese Reg. Guides the following controls were inplanented:

For field fabrications, weld filler materials were required

i to have a weld deposit ferrite content of eight (8) per centminiman. ASME Section III allowable mininun is five (5)percent. All stainless steel welding was performed usinglow heat input welding processes. Preheat and interpasstemperatures were controlled to a 350*F maximan. As analternate to the testing specified in Reg. Guide 1.44, GE

|employed process controls to minimize severe sensitizaticm(i.e., rwhwl weld heat input, control of cold work,control of interpass temperatures, and control of solution,

I heat treatment) .

(d) Repair of field installed non1nitigated welds was notrequired. 'Iherefore, additional sensitization and stresseswere not induced by redundant welding. Non-mitigated fieldwelds were welded with 3/32 inch and 1/8 inch diameterfiller materials.

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The welds were installed in the 2G and SG positions (Ref.ASME Section IX) thus the welding parameters used would beon the lower end or allowable ranges to control weld puddlefluidity. By using the lower of the allowable range (i.e.,volts and anps) the severity of the sensitization isreduced.

:B. Feedwater System ,

'IThe original Feedwater RPV safe ends were renoved and replaced with SA508 C1. I with Ni-Cr-Fe weld metal butter applied to the endpreparations. Balance of feedwater by original design conforms tomaterial selection requirernents of NUREG-0313 Revision 1. See Part2(c) of this Report for material identification.

C. Control Rod Drive

The Control Rod Drive Return has been removed aM capped at the vesselwith Ni-Cr-Fe alloy (Inconel 600) . 'Ihe RPV safe end is SL 508 C1.1.

D. Other Systens

The raterials used in the other systans satisfy the mlectionrequirestents of NUREn-0313 Revision 1. See Part two (2) of thisReport for material identification by systen.

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4. PRESERVICE AND INSERVICE INSPECTIONS - (NBC QUESTION 43)

A. The baseline data for GGNS consist of Ultrascnic Examinations (ITT)using procedures meeting the requirerents of ASME Section XI. Inaddition to the Ur, the ASME Section III Radiographs for both fieldwelds and shop welds are available for baseline data.

.

B. Etir our first refueling outage the following areas will be enhancedary1/or developed: [ ;

1. Training of personnel for implementation of Inservice Inspection(ISI) contractor activities.

2. 'Ihe developnent of improved Ur s uce&res for use in thedetection and characterization of IGSCE.

3. A program for the demonstration of 17r pwcedures and personnel toassure ability and proficiency in the detection andcharacterization of IGSOC. The basis for denonstration will be asa:Tple containing IGSOC obtained frcm Nine Mile Point. Thesanple will be characterized using an improved procedure with aproven capability in addition to other NondestructiveExaminations.

4. 'Ihe program for inservice inspection is being developed toinclude the requirements for augnente3 inspections as specifiedin NUREG-0313 Rev. 1.

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5. FIRMD FU1URE ACTION FDR MITIGATION - (hPC QUESTION #1)

For those welds not yet mitigated plans are being established that will ;

initiate mitigation techniques at our first re-fueling outage. Techniques |

under consideration are induction heating stress inprovement (IHSI) andlast past heat sink welding (LMISW) with eriphasis on IHSI. MP&L has givenGeneral Electric approval to proceed with the manufacturer of IHSI coilsfor use on non-mitigated welds. Future enhancenent (i.e. , hydrogen ,

injection) to water chemistry is dependent on results of research now beingperforned.

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6. )RTER QEMISTRY - (NBC CUESTION #4)

Conductivity, chloride and pH are monitored periodically in the primary coolant.Limits are found in Section 3.4.4 of the GGNS Operating License Manual. 'Iheselimits are within ommonly accepted industry practices and Nuclear RegulatoryOtmmission app m ed values.

'Ihe followin'g systes are periodically nonitored for contaminants to maintainthe above required water quality of the primary coolant systems. [

Reactor Water Cleanup Systen

Control Rod Drive

Water Condensate Systm

Condensate D mineralizer Effluent

Feedwater

Suppression Pool

Condensate Storage Tank

Refueling Water Storage Tank

Oxygen concentration limits are not specified in BWR 'Ibchnical Specificationsbut are included at GCNS as procedural operational requirments for smesystems. In addition to the sanpling and monitoring programs, operationalprocedures provide Instructions that the feedwater heater drains should not bepmped to the feedwater system until the 0 concentration is 20-200 ppb.2

'Ihe oxygen concentrations in the primary system during operation is expected tobe approximately 0.2 ppn. This concentration was used in the GGNS crack growthevaluation (as presented in Section 8A) . Based on the predicted primary systemwater chemistry, the propensity for IGSOC to occur should be within the boundsof analyzed flaw growth characteristics. In addition, a large safety margin isavailable to cmpensate for any water chenistry variances that may be expectedto occur during plant startup and operation.

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7. IEE DETECTICN - (NBC QUESTION #2) l

Several methods of leak detection are used to monitor known and unknownleakage sources at (XNS. 'Ihe follow 2ng reactor coolant leakage systems arerequired to be operable during plant operation (Reference: TechnicalSpecifications, Section 3.4.3.1) .

1) 'Ihe drywell atmosphere particulate radioactivity monitoring system. _

f

2) 'Ihe drywell floor and equipnent drain simp level and floor monitoringsysten.

3) Either the drywell air coolers condensate flowrate nonitoring systenor the dryuell atrosphere gaseous radioactivity nonitoring system.

The purpose of the drywell leak detection subsystem is to nonitor variousparameters in the drywell and to activate annunciators should theidentified or unidentified leakage rates exceed the allowed limits.(Reference: OGNS Safety Analysis Report 7.6.1.4.3.9, "Drywell LeakDetection Status").

The drywell leak detection subsysten consists of the following circuits tomonitor unidentified leakage:

Floor drain nonitoring subsysten. The monitoring subsystem.

activates annunciators when drain flow, simp level, or simptatperature exceed predetermined values.

Airborne radioactivity monitoring. 'Ihe drywell monitoring system.

activates annunciators when the airborne particulate, iodine, orgaseous activity exceeds predetermined values.

Drywell air cooler condensate flow monitoring.

Drywell cooler inlet and outlet cooling water tatperature.

differen

Drywell air tstperature nonitoring.,

Drywell pressure monitoring.

'Ihe drywell leak detection system consists of the following circuits tomonitor identified sources of leakage.

Equipnent drain monitoring subsysten. The monitoring system.

activates annunciators when the drain flow, stmp level, or sumptatperatures exceed predetermined values.

Valve sten packing leakoff monitoring.

Recirculation punp seal monitoring.

Reactor vessel head seal monitoring.

Safety / relief valve nonitoring.

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'Ihe Technical Specification Isakage Limits (Section 3.4.3.2) are givenbelow:

(1) tb pressure boundary leakage

(2) 5 GN unidentified leakage

:(3) 30, GH total leakage ;

'/(4) 2 GH increase in unidentified leakage with any of hour period.

Several diverse means are provided to monitor leakage within the drywell.Isakage in excess of the limits require controlled shutdown andidentification of the source of leakage. Primary systm leakage locationscan be identified by radiological means (pipe mears), aishne isotopicanalysis, hydrostatic tests, ultrasonic inspection and visual inspection.Any or all of these mans may be used to identify degradation of theprimary systan boundary when leakage exceeds the technical specificationlimits.

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8. JUSTIFICATION FOR OPERATION - (NRC CUESTION #2)

A. Fracture Mechanics Evaluation of Flaws

A preliminary fracture mechanics evaluation was performed by GeneralElectric Ccmpany to conservatively estimate the maxinum expected crackgriowth rate of the unmitigated GGNS welds assuming an initial ICBOCflaw existed at plant startup. (Reference: "A Fracture Mechanics ;

'Evaluation of Urrnitigated Recirculation Irop Welds in Grand GulfNuclear Power Station, Unit 1", RSFA #83-45, DRF #137-0010, HSM07,DA,August, 1983). It was further assumed that the postulated crack iscircumferential and extends 360" around the ciremference of the pipewith an initial depth of 5% of the pipe wall thickness.

'Ibe purpose of the evaluaticn was to determine if an undetectedpre-existing crack could grow to a critical flaw size within the timeperiod between plant startup and the first scheduled refueling outage.

The evaluation was performed in accordance with the recently approvedAppendix X to Section XI of the ASME Code, Paragraph IWB-4530," Acceptance Criteria for Flaws in Austenitic Stainless Steel Piping".'Ihe expected crack growth until the next refueling outage ( 2 years)was conservatively based on an assmed 5% initial flaw size. 'Ihefinal calculated size was then ecmpared to the allowable value.

'Ihe evaluation methodology used the worst-case stress and materialproperties information that was readily available frm the ASME Stressreport for the twenty-two (22) unmitigated welds of the 034Srecirculation piping systan. A review of the primary and sustainedstresses at the subject weld locations indicated that the largestccmbination of pressure, weight, and thermal expansicn occurred at theheader-to-cross weld in the 16 inch diameter pipe. Residual axial'

welding stresses were characterized. Data for residual stresses weretaken frm cmbined results of weld stress measurments on largediameter piping reported by G. E., Argonne National Laboratory andSouthwest Research Institute.

In addition, crack growth data corresponding to furnace sensitizedstainless-steel was used in the G. E. analysis for weld sensitizedmaterial in 0.2 ppm oxygenated water. This is a conservativeasstoption since furnace sensitized material is worse than weldsensitized material under IGSOC. 'Ihis additional conservatismprovides margin to account for fluctuations in water chemistry and

| higher oxygen during startup.l With the assmed initial flaw depth of 5% of wall thickness, the

calculated crack dept at the end of 16,000 hours ( 22 months;

| operations tine) is predicted to be 34% of the pipe wall thickness.'Ihis calculated value of final flaw size is well below the ASMESection XI code allowable value of 63% of wall thickness.

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B. Icak-before-Break

Purther, the crack growth characteristics in BWR pipe, is "binodal" innature either the cracks are short and deep or long and relatively ,

'

shallow (Ref.: EPRI Report R.P.1570-2, " Ultrasonic Sizing Capabilityof IGSOC and its Relation to Flaw Evaluation Procedures", dated August4/1983). Welded joint flaws can be categorized into two types short,deep cracks that typically occur in snaller 4-12" diameter pipe, and

'-long shallow cracks that typically occur in larger size piping.

'Ihe stress distribution in large joints have a large cmpressiveresidual stress beginning about 20% through the wall frcra the insidesurface and IGSCC growth rate will be significantly reduced in thisccrpressive region. Consequently, IGSCC progresses very slowly andmay leak only after having been in service for several years, but thepipe will not break. Major weld repairs or other effects that perturbthe stress field may alter the behavior pattern of the joints.However the leak-before-break postulate for stainless steel pipe issupported by extensive field experience and analytical instabilityanalysis. The evidence shows that crack growth is a stable phenmenonand guillotine rupture will not occur.

The umitigated recirculation piping welds at G@S are either 16 inchor 24 inch nminal dianeter. 'Ihe piping is expected to behave as atypical large joint assming major weld repair or other asymetricalperturbances were not introduced during the welding process. A reviewof the welding records of the recirculation piping welds shows that noweld repairs wem made to any of the unmitigated GGNS welds.

Therefore, based on this conservative evaluation, it can be concludedthat the calculated crack growth for the 24 nonth period or until thenext refueling outage is acceptable. 'Ihe flaw growth model assumed inthe GGNS fracture mechanics evaluation is believed to be conservativeand neither leaks nor breaks are expected to occur during theoperating period to the next scheduled refueling outage.

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SLM ERY

For all the systes that make up the Reactor Coolant Pressure Boundary (RCPB)only the Recirculating Water syst s contains materials which do not meet theselection requirments of NURDG 0313 Rev.1. Approximately 740 butt welds wereused in the ,assably of the BCPB. 'Ihere are 128 welds in the IGSOC susceptibleportions of the systern, of these only 22 are not mitigated. In omparison to ,

the overall ofCPB this represents 3 percent of the total welds. "

All 304 grade materials were solution annealed and quenched to eliminate furnacesensitization; all cast products meet the selection requirernents of NURD3 0313Rev. 1; all weld filler materials used were either nickel base (for buttering)or Type 308L with ferrite in excess of 5 percent. '1he only areas within therecirculating water systs sureptible to IGSOC are the heat affected zones ofthe non-mitigated welds.

Mitigation techniques will be inplernented at the first refueling outage. Alsoat that time, the ISI program will include inproved Ur Procedures and theAucynented Inspection Program.

It's evident frm the fracture mechanics evaluation that any IGSOC's inducedduring the operational period prior to first refueling outage will not create asafety concern. Sufficient leak detection has been provided to arrest anyadditional safety concerns towards undetected leakage due to IGSOC. HistoricalData is still supporting leak before break. Grand Gulf will maintain waterchmistry in accordance with GGNS Operating License Manual.

Based on the information presented in this report, MP&L concludes the following:

1) G@S is justified for operation until the firstrefueling outage.

2) After mitigation of the twenty-two (22) vulnerablewelds, further problerns with IGSOC is not anticipated.

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APPENDIX A

IGSOC MITICATION

bFtL1rIC JOINT INE0R%TICN

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SPECIFIC JOINT INFOINATION i

IOOP A

W #1: This weld has had a mitigation technique applied.

Safe-ehd - 316L SS,.

.I,

Pipe / 304 SS, shop clad and solution annealed prior to welding. F.

W 42: This weld has had a mitigation technique applied.

Pipe - 304 SS, shop clad and solutioned anrealed prior to welding..

W #4: This weld has had a mitigation techniuge applied.

Elbow - 304 SS, shop clad and solution annealed prior to welding..

Valve - SA351, CF8M, 0.06% C, Ferrite = 13.5%.

W 45: Not Mitigated (SRI = 1.08)

Valve - SA351, CF8M, 0.06% C, Ferrite = 13.5 %.

Pipe - 304 SS, 0.05% C, solution annealed prior to welding..

W #6: Not Mitigated (SRI = 1.15)

Elbow - 304 SS, 0.05% C, solution annealed prior to welding..

Punp - SA351, CF8M, 0.69% C, Ferrite = 16%.


Punp - SA351, CF8M, 0.069% C, Ferrite = 16%.

Pipe - 304 SS, 0.05% C, solution annealed prior to welding.


Pipe 304 SS, 0.05% C, solution annealed prior to welding..

Valve - SA351, CF8M, 0.05% C, Ferrite - 11.8%.

W 49: 'Ihis weld has had a mitigation technique applied.


Pipe - 304 SS, shop clad and solution annealed prior to welding..

W #10: This weld has a mitigaticn technique applied.|

| Pipe - 304 SS, shop clad and solution annealed prior to welding..

|


Sheet 2 of 7

* .

*.

SPECIFIC JOINT INEGMATION

I OCTP A (Cont'd) j

W #11: Not Mitigated (SRI = 1.03) 1

I,

Valve.'- SA351, CF8M, 0.04% C, Ferrite = 12%.

:.

Pipe f 304 SS, 0.052% C, solution annealed prior to welding. '.



Reducing Cross - SA 403, 304 SS, 0.070% C, solution annealed prior to.

welding.

m #13: 'Ihese welds have had a mitigation technique applied.

Sweepolet - 304 SS, field clad prior to welding..

Riser Pipe - 304 SS, shop clad and solution annealed prior to welding..

N #14: These welds have had a mitigation technique applied.

Riser Pipe - 304 SS, shop clad and solutico annealed prior to welding..

Safe-end - 316L SS.

W #15: ' Itis weld has had a mitigation technique applied.

Pipe - 304 SS, field clad prior to welding..

Pipe - 304L SS.

SW #1: Not Mitigated (SRI = 1.13)


Cap - 304 SS, 0.048% C, solution annealed prior to welding,.

t

' SW #2: Not Mitigated (SRI = 1.13){l Pipe - 304 SS 0.055% C, solution annealed prior to welding..

!' Cap - 304 SS 0.048% C, solution annealed prior to welding..

SW #3 & SW #4: Not Mitigated (SRI = 1.20)

Reducing Cross - SA403, 304 SS, 0.070% C, solution annealed prior to.

welding.

| Pipe - 304 SS, 0.055% C, solution annealed prior to welding.-.

'

Sheet 3 of 7

- _ - - - . - --

. . . . -

. . .

.

SPEXHFIC EINT INEGMATION

IDOP A (Cont'd)~

SW 45: Not Mitigated (SRI - 1.13)

Reducihg Cross - SA403, 304 SS, 0.070%, solution annealed prior to.

welding. ;,

I tCap - SA403', 304 SS, 0.070% C, solution annealed prior to welding..

,

!

Il

I,

ISheet 4 of 7

_ . - . . _ _ .- __

__-_______ ________-______ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ - _ _

.

*.

'

SPECIFIC JOINT INFORMATION (

IDOP B>

W #1: h is weld has had a mitigation technique applied.

Safe-gxi - 316L SS.

Pipe /304 SS, shop clad and solution annealed prior to welding. d.

W #2: his weld has had a mitigatica technique applied.

Pipe - 304 SS, shop clad and solutioned annealed prior to welding..

W #3: his weld has had a mitigatico technique applied.

Pipe - 304L SS.

Tee - 304 SS, shop clad and solution annealed prior to welding..

m 44: h is weld has had a mitigation techniuge applied.

Elbow - 304 SS, shop clad and solution annealed prior to welding..



Valve - SA351, CF8M, 0.06% C, Ferrite = 14.5 %.



Elbow - 304 SS, 0.050% C, solution annealed prior to welding..

Purtp - SA351, CF8M, 0.60% C, Ferrite = 16%.

N #_7 : Not Mitigated (SRI = 1.00)

Purip - SA351, CF8M, 0.060% C, Ferrite = 16%.

Pipe - 304 SS, 0.052% C, solution annealed prior to welding.


Pipe 304 SS, 0.052% C, solution annealed prior to welding..

Valve - SA351, CF8M, 0.050% C, Ferrite - 17%.

N #9: W is weld has had a mitigation technique applied.

Valve - SA351, CF8M, 0.050% C, Ferrite = 17%.

Pipe - 304 SS, shop clad and solution annealed prior to welding..

Sheet 5 of 7

_______

- .

.

SPECIFIC JOINT INFOIDRTION

IDOP B (Cont'd)-

N #10: ' Itis weld has a mitigation teqhnique applied..

Pipe ,304 SS, shop clad and solution annealed prior to welding..

Valve g SA351, CF8M, 0.050% C, Ferrite = 11.5'a i.

N ell: Not Mitigated (SRI = 1.03)




Pipe - 304 SS, 0.051% C, soluticn annealed prior to welding.| .

|

Reducing Cross - SA 403, 304 SS, 0.070% C, solution annealed prior to| .

welding.,

|N #13: h se welds have had a mitigation technique applied.

Sweepolet - 304 SS, field clad prior to welding..


| N 014: hse welds have had a mitigation technique applied.


Safe-end - 316L SS.

m 415: ' Itis weld has had a mitigation technique applied.

Pipe - 304 SS, field clad prior to welding..

Pipe - 304L SS.

SW #1 & SW #2: Not Mitigated (SRI = 1.13)

Pipe - 304 SS, 0.055% C, soluticn annealed prior to welding..

Cap - 304 SS, 0.048% C, solution annealed prior to welding..

SW 43 & SW 64: Not Mitigated (SRI = 1.20)~

Reducing Cross - SA403, 304 SS, 0.070% C, solution annealed prior to.

welding.


Sheet 6 of 7

.. . . . .. .. .

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _

.. - ._ .. -- - .- _ - - . _ _ _ _ - . -. .-

* .*

,

SPECIFIC JOINF INFOft9CICE

IOOP B (Cont'd)

SW #5: Not Mitigated (SRI - 1.13),

Reducipg Cross - SM03, 304 SS, 0.070%, soluticm annealed prior to.

welding.*

/ [Cap 'SM03', 304 SS, 0.070% C, soluticn annealed prior to welding. -

.

j

-i

!

,

.

I

Sheet 7 of 7

_ _ . - -. . . . . . - . . . . .

h) m d [ zi r. s. iawis

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