NuElCommitted to Nuclear &xcelenf" Point Beach Nuclear Plant

Operated by Nuclear Management Company, LLC

NRC 2003-0056

June 10, 2003

U.S. Nuclear Regulatory CommissionATTN: Document Control DeskWashington, DC 20555

DOCKET 50-301; LICENSE NO. DPR-27POINT BEACH NUCLEAR PLANT, UNIT 2SUBMITTAL OF THE AUXILIARY FEEDWATER ORIFICE ISSUE REGULATORYCONFERENCE SLIDE PRESENTATION

Ladies/Gentlemen:

On June 6, 2003, a regulatory conference was conducted between representatives of the NuclearManagement Company, LLC (NMC) and members of your Staff to discuss the AuxiliaryFeedwater Orifice Issue at Point Beach Nuclear Plant (PBNP). During the presentation, aquestion was raised regarding the installation date, shown on slide eight, of the "A" motor drivenauxiliary feedwater pump recirculation line orifice. A review perfonned following theconference determined that the date presented was incorrect and should have reflected aNovember 2000 installation date. This error did not impact the risk analysis discussed at theconference.

The attached slide presentation is provided for your use. Based on the error identified above,three slides; eight, twenty, and twenty-one have been corrected. Additionally, slide eight hasbeen clarified to reflect the "A" and "B" designation of the motor driven auxiliary feedwaterpumps.

If you have any questions, please contact Gordon P. Arent at 920/755-6518.

-F ort 6590 Nuclear Road * Two Rivers, Wisconsin 54241

Telephone: 920.755.2321

NRC 2003-0056June 10, 2003

cc: (w/o enclosure)Project Manager, Point Beach Nuclear Plant, NRR, USNRCRegional Administrator, Region 111, USNRCNRC Resident Inspector - Point Beach Nuclear PlantPSCW

Point Beach Nuclear PlantRegulatory Conference Concerning Auxiliary

Feedwater Orifice Issue

June 6, 20031

Agenda

Purpose/Obj ective

Overview

Root Cause Analyses

SignificanceDetermination

Closing Remarks

Mano Nazar

Fred Cayia

Fred Cayia

Mark Reddemann

Mano Nazar

2

i ;; : I i . .

I : - - i:0 AiME i

Purpose

) Provide Overview of Auxiliary FeedwaterSystem Orifice Issue

> Discuss Root Cause Evaluation of the AFWOrifice Issue

> Present Methodology and Conclusion of theNMC/Point Beach SignificanceDetermination Process for AFW OrificeIssue

3

Objective

> Present New Information and ConsiderationsConcerning Issue Significance

> Provide NMC's Position on theCharacterization of the Apparent Violation of10 CFR 50, Appendix B, Criterion III "DesignControl"

4

JDD

::llm::

Overview

5

Overview

Auxiliary Feedwater System

Fire Water Conn(4 total)

OverviewTimeline of AFW System Improvements

Feb. 1981GL 81-14 issued(AFW seismicqualifications)

March 1979

Accident

Sept 1986Added SR EQ level

transmitters for CST(TMI response)

May 1982NRCSER,

NUREG-0737Item ELL1.2,NRC accepts

"safety grade"status of AFWauto initiation

Aug 1984Added AFW

dischargeMOV coutrols

(FMIresponse)

1980

April 1993Installed air line

to allow ISTtesting of AFW

recirculationvalves

1991Added recirc flowinstruments and

larger recirc lines andorifices to increaserecirc flow to 70 &

100 GPM

July 1997Missile

protectedportions of

AFW suctionpiping

July 1997Added AFW

discbarge valvebackup nitrogensupply; installedcable separation

modifications

1990

Note: At time of licensing,AFW was not safety related

July 1981Added AFW supplyline flow indication(TMI response)

1985Added low suction

pressure trip(TMI respone-

W v a3II W. auU June 1988 pressure tripPoint Beach response tIp

Nov 1983 to IEB 88-04 r March 1999Added AFW (review of AFW Nov 1995 Modification to

inoperable alarm minimum flow) Added SW flush assure control(TMI response) identifies need for connection at AFW wire separation

greater recirculation pump suctions for AFW systemflow capability s

March 2003Proper(larger)orifices

installed onall AFW

recirc liues

I

Oct 1970Ul Licensed

Sept2002AFW

recirculationdesignated

safetyI function

Jan 2002

NRCinspection ofModifications/50.59

1970

I ;000: : S : 0: :

- : :: : '

I

Overview

Recirculation Line Orif ce

Discussion:> Orifice Modification Developed in 2000 to Reduce Recirculation

Line Cavitation

> Recirculation Line Orifices- Modification History

_______ _______ _______ ______ Pum p A Pum p B

Motor Driven AFW Pumps (MDAFP) June 2000 June 2000Modification issued

MDAFP Modification Installed November November2000 2000

Unit 1 Unit 2

Turbine Driven Auxiliary Feedwater Pump March 2002 December(TDAFP) Modification Issued 2001

TDAFP Modification Installed October May 20022002

OverviewRecirculation Line Orif ice

Description:

Potential for Fouling of Recirculation Line Coincident withProcedurally-Directed Operator Action to Secure AFW ForwardFlow.

> Identified by NMC Following System Testing of the Motor DrivenAFW Pump

> Orifice Plugging Could Occur When AFW Pumps Were Aligned toService Water Resulting in Potential Common Mode Failure

> Prompt Corrective Actions

* All Four AFW Pumps Declared Out-of-Service Due toPotential Recirculation Orifice Common Mode Failure

* Compensatory Actions Established to Direct Operators toSecure AFW Pumps in the Event Minimum Recirculation FlowCannot be Maintained

9

Root Cause Analyses

10

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Root Cause AnalysesUbJ hAFWRecirculation Orifice

> Root Cause-Orifice Issue (RCEOOO 191)

eFailure to Properly Evaluate the Potential forOrifice Plugging Within the Design Process

> Contributing Causes

*Use of Unverified Information and the Omissionof Key Design Information in the SafetyEvaluation for the Orifice Modification

11

Root Cause AnalysesAFWRecirculation Orifice

> Corrective Actions- Complete

* Increased Engineering Management Involvement inApproval and Oversight of Modifications

* Implemented Periodic Review of EngineeringProducts by a Quality Review Team

* Presented Lessons Learned to EngineeringPersonnel Stressing the Use of the Design Process

* Revised Training Materials to Accurately ReflectAFW Recirculation Line Design Functions

* Orifice Redesigned, Tested and Installed on allFour Pumps in March 2003

12

Root Cause Analyses

_~ AFWAir Operated Valve Finding

Missed Opportunitk (RCE 01-069)> The Root Cause Problem Statement Focused on Emergency

Operating Procedure (EOP) Limitations Related to a Loss ofInstrument air event.

> The Root Cause Problem Statement should have Focused on thePotential Loss of Recirculation Flow.

> The Extent of Condition Evaluation would then have InvestigatedConditions in Addition to a Failed Closed AFW AOVrecirculation valve.

> Examples of Possible Loss of Recirculation Failures would haveIncluded:

* Orifice Plugging* Electrical! Control System Failures

Indication Failures

13

I

ijr

Root Cause AnalysesComprehensive AFW Evaluation

> Root Cause-Comprehensive AFW Evaluation (RCE000202)

* Failure to Consider the Integration of AFW SystemDesign and Accident Progression (RC-1)

* Less than Adequate Knowledge of the SafetySignificance of the AFW Recirculation Line inProtecting the Pumps (RC-2)

> Contributing Causes

* Lack of Problem and Issue Ownership (CC- 1)

* Corrective Action Program Weaknesses

* Less than Adequate Engineering / Operations Interface(CC-2)

* Less than Adequate Management of the Inter-Relationship of Documents (CC-3)

14

Root Cause AnalysesComprehensive AFWEvaluation

> Prompt Corrective Actions- Complete* Placed Modifications Developed using "Old Process" on

Installation Hold Pending Accident Progression Review

* Implemented Multi-Discipline Review of ProposedModifications by Management Team

> Interim Corrective Actions- Complete

* Implemented New Fleet Modification Process

* Implemented Design Review Board* Assigned Issue Managers for Significant Station Issues* Conducted Detailed Review of AFW Design and Licensing

Bases (RC-2)* Implemented the Corrective Action Program Improvements

15

Root Cause AnalysesComprehensive AFW Evaluation

Additional Corrective Actions:

> Enhance Understanding of System Design and AccidentProgression (RC-1)

* Upgrade Modification Process and EOP/AOP change process

* Develop and conduct training for Engineering and Operations

> Resolve Remaining Issues from AFW Design and Licensing Bases(RC-2)

> Develop and Conduct Training on AFW Design Bases (RC-2)

> Strengthen the Role of Engineering in the Development/Revisionof Operations Procedures (CC-2)

> Upgrade Electronic Document Management System (CC-3)

> Continue Implementation of Corrective Action ProgramImprovements

16

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Signif cance Determination

17

Signif icance DeterminationHistorical Timeline

Sept 2002AFW reclrcAOV open-

functiondesignated

safety related

Key:Recirculation Line OrificeRecirculation Line AOV

A

Nov 2000A&BMDAFW

pump anti-cavitation orifice

Installed

tL

Dec 2001U2 TD AFW pump

anti-cavitation orificemodification issued

May 2002U2 TD AFW pump

anti-cavitationorifice installed

I _- I I I : . 4 - . I : : I M 0 a : fl

2001June 2000

A & B MD AFW pumps'anti-cavitation orificemodMications Issued

Nov 2001*Identification

of recirc Hue AOVissue.

T2002

March 2002Ul TD AFW pump

anti-cavitation orificenodification issued

* Proceduresmodified tomonitor recircAOV position andlow instrument airheader pressurealarm to ensureminimum AFWflow

May/June 2(Instaled safirelated back

N2/air to aAFW recir

AOVs

L March 2003Replacement

Qarger)orifices

instaled On allAFW recrc

Ihles

+ 1 t 2003Oct 2002*UI TD AFW pumpanti-cavitation orificelnstalled

* Potental for orificepluggiug Identifiedwhile testing A MD

W02 AFW pump a fewety weeks laterupii * Procedures modifiedc to rely on forward

flow to ensure min 18flow

2000 4.

l

I

Signif icance DeterminationEvents Affected by Orif ces

Dual Unit Events> Loss of Offsite Power> Loss of Service Water> Loss of Instrument Air (Minor)

> Loss of DC Bus D02

Single Unit> Transient (Minor)> Transient without Heat Sink> Steam / Feed Line Break (Minor)> Loss of Component Cooling Water (Minor)

19

* AS ;;~~~~~~~~~~~~~~~~~~~~~~~~

i .

Significance DeterminationNMC

Orifice Risk Increase- Unit I *

Risk due to orificeplugging > I year

from identiication

Risk due toorifice plugging

mitigated byprocedurechanges

AZ __-- --

Nov 2000A&BMDAFW

2000

*Fraction of yearCDP affected by all3 AFW pumps forUnit 1= 0.06

Sept 2002Recirc AOV open-

function safetb relatedDec 2001

U2 TD AFW pumporifice mod issued

2001June 2000

A & B MD AFW pumps'orifice mods issued Nov 2001

*Identification

2002 March 2002Ul TD AFW pump

anti-cavitation orificemodification issued

of recirc line AOV May/June 2002Issue Installed AOV*Procedures backup N2/airmodified

March 2003New orifices

iustalled on allAFW recirc

lines

V 2003Oct 2002

- Ul TD AFWpump orificeinstalled

* Plugging Identified

* Procedures 20changed

CalculatedBase - -

Risk

I.--

... ,.,.,a ,

I

._________________t

Significance DeterminationNMC

Orifice Risk Increase-Unit

CalculatedBase - - -

Risk

2**

Risk due to orifice ;plugging > 1 year

from identification I

--- - - - - - - - - - - - - - -v

Risk due toorifice plugging

mitigated byprocedure

changes

Wilion 1/

/IA,_ _ _ _ _ _ _ __--

Nov 2000A& B MD AFW

pump orificeinsfd

June 2000A & B MD AFW pumps'

orifice mods issued

Sept 2002Recirc AOV open-

function safety related

Dec 2001U2 TD AFW pumporifice mod issued

2001

Nov 20*Identificatiaof recirc linIssue*Proceduresmodified

**Fraction of yearCDP affected by all3 AFW pumps forUnit 2= 0.472

May 2002U2 TD AFW pump

orifice installed

A

2002 March 2002

Ul TD AFW pumpantiavitation orifice

01 modification issued

e AOVI

May/June 2002Installed AOVbackup N2/air

March 2003New orifices

installed on allAFW recirc

lines

I~~

2003Oct 2002

* Ul TD AFWpump orificeInstalled

* Plugging identified

* Procedureschanged 21

2000

- -

-% I I I f - A ; - 1_ _,_ I Ai _ I '' 1

amioSL

Significance Determination- Event TimelinesEvents

Dual Unit Events

*Loss of Offsite Power, Lossof Instrument Air, Loss ofDC Bus D02, Loss of ServiceWater

Single Unit Events

-Transients without HeatSink

*Transient without Heat Sinkand No Water Treatment

-Small LOCA

-Steam Generator TubeRupture

-Main Steam Line Break(Inside Containment)

-Main Steam Line Break(Outside Containment)

Time to CST Low-Low Level

With Water TreatmentSystem Clearwell

4. 4.

1.6 Hrs

Not Required

2.1 Hrs

5.1 Hrs(0.5" Break Only)

3 Hrs

3.3 Hrs

1.6 Hrs

System Not Available

Not Required

System Not Available

Not Required

9.7 Hrs

12 Hrs

Not Required

Time to InitiateFeed & Bleed(If Required)

4.8 Hrs

Not Required

5.5 Hrs

Not Applicable

Not Applicable

15 Hrs

Not Required

Notes

Normal CST MakeupAvailable

Three break sizes, with andwithout safety injection. Onlysmallest break reaches CSTLow-Low Level

RHR conditions reached onCST inventory at -2.2 hrs-prior to reaching SG levelrequiring feed & bleed.

22

Signif icance DeterminationDiferences for Plugged Orif ice

> AFW Swap-Over Occurs Hours After Reactor Trip

*Decay Heat Lower

*Charging Successful for Feed and Bleed

*Shutdown Cooling Credited

* Steam Generator Depressurization and ServiceWater /Fire Water Addition Possible

*Emergency Response Facilities Staffed

*More Time for Troubleshooting and Recovery

23

Significance DeterminationNRC

9 Preliminary Evaluation of Risk Increase Basedon Phase 2 Analysis

> Assumed AFW Failure Probability of 1.0

> No Credit for:

* Initial Cooling by AFW

* Charging Feed and Bleed

* Transition to Shutdown Cooling

* Service / Fire Water Addition

24

Signif icance Determination

NMC

> Internal Events Evaluated Probabilistic RiskAssessment

* MAAP (Modular Accident Analysis Program)used to Demonstrate Success and DetermineTimeline of Recovery Actions

* Human Reliability Analysis for CreditedRecovery Actions

> Seismic Events Evaluated using Seismic PRA

> Fire Event Analysis in Progress

25

Significance DeterminationNMC Risk Mitigating Factors

Incorporated

> Water Treatment System

* Makeup to Condensate Storage Tank

* Clearwell Tank Makeup to CST

* Recovery Following Restoration of Off-Site Power

> Service/Fire Water through Disabled AFW Pump

> Charging for Feed and Bleed

26

Signif icance DeterminationNMC Risk Mitigating Factors

Incorporated (cont'd)

> Changes to HEPs for Feed and Bleed

> Recovery of SI/ RHR

Incorrect Position

; Operators Starting/Stopping AFW Pumps

to Avoid Failure of 2nd andlor 3 rd Pump

27

Valves Left in

. , 11

m

Significance DeterminationNMC Risk Mlitigating Factors Not

Incorporated

> Available 14,000 Gallons of Water Left in EachCST at Low Low Level

> Increase Charging to Maximum While in Loss ofHeat Sink Procedure

> Likely AFW Pump Survival Time FollowingSwap-Over to Service Water

* Valve Leakage* Packing Leakage

> Alignment of N 2 to Pressurizer PORVs FollowingLoss of IA

28

Signif icance DeterminationLargest Contributors to Risk

Largest Contributors Recovery Credited

Initiator Water Service I Charging ShutdownTreatment Fire Water Feed & Cooling

Bleed

Loss of Offsite Power- x x x xDual and Single Unit

Transient w/o Heat Sink x x x

Loss of DC Bus 2 x x x

Loss of SW x

29

tI

i

o

Significance DeterminationSensitivity Analysis

30

Factor Contribution to CDPReduction (%)

Water Treatment System Impacts 91

Service Water/Fire Water through AFW Pump 48

Feed and Bleed HEP Change 48

Charging for Feed and Bleed 19

SI / RHR Valve Recovery HEP 10

Start / Stop AFWPs 5

Signif icance DeterminationResults

Internal Events> Increase in Internal Events Core Damage

Probability* Unit 1: High White* Unit 2: Mid Yellow

31

Significance DeterminationResults

External Events- Seismic

) Fragility Analysis Performed

> Charging, CST, and Service Water AdditionCredited Following Safe Shutdown Earthquake

> Increase in Seismic Initiated Core DamageProbability

* Unit 1: Green

* Unit 2: Green

32

Signif icance DeterminationResults

Increase in Internal Event and Seismic Initiated CoreDamage Probability>Unit 1: High White

>Unit 2: Mid Yellow

33

:: . .I = -t: 00 0 > D. f.

Significance DeterminationResults

External Events- Fire>Fire PRA Model Not Developed>Development is in Progress>Method Includes:

* Fire Initiation Frequency* Detection Probability* Automatic and Manual Suppression Probability* Identification of Cables and Determination of

Equipment Affected* Credit for Mitigating Factors* Consequences of Unsuppressed Fires

>Completion Targeted in August

34

Summary

> Installation of Inappropriate Orifice Design was RiskSignificant

> NMC Significance Determination Preliminary Results(Internal and Seismic)

* Unit 1: High White* Unit 2: Mid Yellow* Final Results, Including Fire, Targeted in August 2003

> Further AFW System Modifications* Electrical Modifications in Progress* Margin Recover Study

> Engineering Excellence Plan

35

Closing Remarks

> AFW Orifice Issue Self-Identified and Resolved inTimely Manner.

> AFW System Today is more Reliable.> NMC Understands the Importance of the AFW

Orifice Issue.

> NMC Significance Determination PreliminaryResults (Internal and Seismic)

* Unit 1: High White• Unit 2: Mid Yellow

> SDP for Fire Events Remains a Work in Progress.> NMC Concurs with the Characterization of the

Apparent Violation of 10 CFR 50 Appendix B.36