ML093210487

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Summary of Regulatory Conference with Ameren Ue Regarding Callaway Plant
ML093210487
Person / Time
Site: Callaway Ameren icon.png
Issue date: 11/17/2009
From: Miller G B
NRC/RGN-IV/DRP/RPB-B
To: Heflin A C
AmerenUE
References
Download: ML093210487 (24)
v • d • e


Text

UNITED STATESNUCLEAR REGULATORY COMMISSIONREGION IV612 EAST LAMAR BLVD, SUITE 400ARLINGTON, TEXAS 76011-4125 November 17, 2009 Mr. Adam C. Heflin, Senior Vice President and Chief Nuclear Officer

AmerenUE P.O. Box 620 Fulton, MO 65251

SUBJECT:

SUMMARY

OF REGULATORY CONFERENCE WITH AMEREN UE REGARDING CALLAWAY PLANT

Dear Mr. Heflin:

This refers to the public meeting conducted at the U.S. Nuclear Regulatory Commission Region IV office on November 9, 2009 during which a regulatory conference was held.

Topics discussed during the meeting included the significance, cause, and corrective action associated with an apparent violation involving the inoperability of the turbine driven auxiliary

feedwater pump. The apparent violation is discussed in NRC Inspection Report 05000483/2009009 (ADAMS ML092730656). Members of the public present at the meeting were allowed to ask questions and comment on the proceedings.

In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter and its enclosures will be made available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRC's document system (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).

Should you have any questions concerning this matter, I will be pleased to discuss them with you.

Sincerely,

/RA/ Geoffrey Miller, Chief Project Branch B Division of Reactor Projects

Docket: 50-483 License: NPF-30

Enclosures:

1. Attendance List
2. Presentation Slides AmerenUE cc w/

Enclosures:

Mr. Luke H. Graessle Director, Operations Support

AmerenUE P.O. Box 620 Fulton, MO 65251

E. Hope Bradley Manager, Protective Services AmerenUE P.O. Box 620 Fulton, MO 65251 Mr. Scott Sandbothe, Manager

Plant Support

AmerenUE P.O. Box 620 Fulton, MO 65251

R. E. Farnam Assistant Manager, Technical

Training

AmerenUE P.O. Box 620 Fulton, MO 65251

J. S. Geyer

Radiation Protection Manager AmerenUE P.O. Box 620 Fulton, MO 65251

John O'Neill, Esq. Pillsbury Winthrop Shaw Pittman LLP 2300 N. Street, N.W. Washington, DC 20037

Missouri Public Service Commission P.O. Box 360 Jefferson City, MO 65102-0360

Deputy Director for Policy Department of Natural Resources P.O. Box 176 Jefferson City, MO 65102-0176 Institute of Nuclear Power Operations (INPO)

Records Center

700 Galleria Parkway SE, Suite 100

Atlanta, GA 30339 AmerenUe

Mr. Rick A. Muench, President and Chief Executive officer

Wolf Creek Nuclear Operating Corporation P.O. Box 411 Burlington, KS 66839 Kathleen Logan Smith, Executive Director and Kay Drey, Representative, Board of Directors Missouri Coalition for the Environment 6267 Delmar Boulevard, Suite 2E St. Louis, MO 63130

Mr. Lee Fritz, Presiding Commissioner Callaway County Courthouse 10 East Fifth Street Fulton, MO 65251

Director, Missouri State Emergency Management Agency P.O. Box 116 Jefferson City, MO 65102-0116 Mr. Scott Clardy, Administrator Section for Disease Control

Missouri Department of Health and

Senior Services P.O. Box 570 Jefferson City, MO 65102-0570

Certrec Corporation 4200 South Hulen, Suite 422 Fort Worth, TX 76109 Mr. Keith G. Henke, Planner II Division of Community and Public Health

Office of Emergency Coordination

Missouri Department of Health and Senior Services 930 Wildwood Drive P.O. Box 570 Jefferson City, MO 65102

Chief, Technological Hazards Branch FEMA Region VII 9221 Ward Parkway, Suite 300

Kansas City, MO 64114-3372 AmerenUe

Electronic distribution by RIV:

Regional Administrator (Elmo.Collins@nrc.gov) Deputy Regional Administrator (Chuck.Casto@nrc.gov)

DRP Director (Dwight.Chamberlain@nrc.gov)

DRP Deputy Director (Anton.Vegel@nrc.gov)

DRS Director (Roy.Caniano@nrc.gov)

DRS Deputy Director (Troy.Pruett@nrc.gov) Senior Resident Inspector (David.Dumbacher@nrc.gov) Resident Inspector (Jeremy.Groom@nrc.gov)

Branch Chief, DRP/ (Geoffrey.Miller@nrc.gov) Senior Project Engineer, DRP/ (Peter.Jayroe@nrc.gov)

Project Engineer, DRP / (Greg.Tutak@nrc.gov)

Site Secretary, DRP/ (Dawn.Yancy@nrc.gov) Public Affairs Officer (Victor.Drocls@nrc.gov)

Team Leader, DRP/TSS (Chuck.Paulk@nrc.gov RITS Coordinator (Marisa.Herera@nrc.gov)

Regional Counsel (Karla.Fuller@nrc.gov) Congressional Affairs Officer (Jenny.Weil@nrc.gov)

OEMail Resource OEDO RIV Coordinator, (Leigh.Trocine@nrc.gov)

ROPreports

R:\_REACTORS\_CW\2009\CW REG CONF MS 110909.doc SUNSI Rev Compl. Yes No ADAMS Yes No Reviewer Initials GM Publicly Avail Yes No Sensitive Yes No Sens. Type Initials GM SPE:DRP/PBB BC:DRP/PBB PAJayroe GBMiller /RA/ /RA/ JClark for 11/12/2009 11/12/2009 OFFICIAL RECORD COPY T=Telephone E=E-mail F=Fax

1 1 NRC Regulatory Conference NRC Regulatory Conference

____Callaway PlantCallaway Plant TDAFP Failure to Start 5/25/09 TDAFP Failure to Start 5/25/09November 9, 2009 2 2Regulatory Conference Presentation OutlineIntroductionFadi DiyaRisk Assessment Dave ShaferQualitative EvaluationsFred BiancoRisk Assessment QuantificationDave ShaferSummaryGreg BradleyCorrective ActionsLes KanuckelClosingFadi Diya 3 3 IntroductionCircumstances leading up to the event are unacceptableMay 25, 2009 failure of the Turbine Driven Auxiliary Feedwater Pump (TDAFP) to startoThe valve actuator was manually operated in the as found conditionoFollowing lubrication the valve tested satisfactorilyThe performance deficiencies constitute violations of Federal Regulations (September 30, 2009 Special Inspection Report)Ameren is not contesting the violationsWe will provide information relative to the risk assessmentWe will describe our extensive corrective actions 4

4 Risk AssessmentAreas of Agreement

Quantification of unrecovered internal events risk Quantification of external events risk (fires & flooding)Trip throttle valve can be locally operated manually 5 5 Risk AssessmentWe will provide additional information in the following areas:Ergonomics Available TimeoDiagnosis phaseoAction phase 6 6 NarrativeMay 25, 2009 at 1141, Operations commenced Surveillance TestingAuxiliary Feedwater Actuation Signal (AFAS) relays actuated as expectedMain Steam supply valves opened as expectedThe TDAFP failed to startInitial investigation determined the actuator had stopped just prior to latching the valveoMain Control Board (MCB) indicationsoLocal observations oReview of drawings 7 7 Narrative (Cont)Investigation and RepairTorque switch stopped valve movementoManually operated actuator (as found condition)oIt would have taken 2-3 turns to latch valve and make-up limit switch. The actuator would then have opened the valve (in an actual station blackout event)Lubricated the trip throttle valve spindle and sliding nut and stroked the valve actuator several timesSuccessfully performed post maintenance testing and the TDAFP was declared operable 5/25/09 at 2056 8 8ErgonomicsFactors Important to Ergonomics
Equipment displays & controlsInstrumentation information (quality, quantity and diversity)Interaction of the operator with the equipmentEquipment layoutEnvironmental conditions 9 9Ergonomics -Qualitative EvaluationActions for recovery of the TDAFP with a station blackout (SBO) place additional challenges on the Operations crewTrainingThe use of diverse indicationsProcedures We will restore auxiliary feedwaterflow from the TDAFP prior to Steam Generator (S/G) dryout 10 10Ergonomics -TrainingLicensed Operator Auxiliary FeedwaterInitial Licensed Training Continuing Training oECA 0.0, Loss of All Alternating Current (AC) Power -24 month frequencyoCritical Safety Function (CSF) -12 month frequencyNon Licensed Operator -Operations Technician (OT)

Auxiliary FeedwaterInitial Training -Secondary ClassroomContinuing Training -36 month frequencyOn the Job Training 11 11Ergonomics -Control Room Indication -Normal OperationPump Speed and Setpoint Steam Supply Steam SupplyTrip Throttle Valve PositionOverspeed Reset Lamp Pump Discharge PressureTrip Throttle Valve Hand Switch 12 12Ergonomics -Control Room Indication

-SBO No TDAFP 13 13Ergonomics -TrainingTrip throttle valve is a unique valve, the only one like it in the plantActuator must go in the closed direction to latch the valve, then will reverse direction and open the valveoOperators are trained specifically on this valveoManually operate the trip throttle valve to start the TDAFP 14 14Ergonomics

-Indication

-Trip Throttle ValveLatch Up Lever Trip Hook 15 15Ergonomics -Governing Procedures -

SBOECA 0.0, Loss of All Alternating Current (AC) PowerDirects the operator to check AFW flowGives the guidance for restoring the TDAFPCSF-1, Critical Safety FunctionsRed Path on Heat Sink -maintains the priority of the control room staff to restore flow from the TDAFP to restore a heat sink 16 16Ergonomics -Governing ProceduresMultiple priorities during a SBO:Loss of AFW flow -Failure of TDAFP to startLoss of Offsite PowerTwo Emergency Diesel Generators (EDG) failure to startLOSS of ALL AC Power (ECA 0.0) MANAGES these prioritiesStep 4 Response Not Obtained (RNO) ECA 0.0 dispatch secondary Operations Technician (OT) to the TDAFPStep 5 ECA 0.0 Reactor Operator will start process of Restoration of Offsite Power, then Step 7 will dispatch OTs to EDGsStep 13 RNO requires MAINTAIN AFW flowStep 16 requires CHECK of SG level above 7% and MAINTAIN AFW flowStep 23 requires CHECK AC emergency buses and RNO loops back to Step 11Procedure use drives priorities 17 17Ergonomics -Governing Procedures (cont)Loss of all AC Power procedure 18 18Ergonomics -Governing Procedures (cont)CSF-1, Critical Safety FunctionsContinuously monitored when in Emergency ProcedureRed Path on Heat Sink -maintains the priority of the control room staff to restore flow from the TDAFP to restore a heat sink 19 19Ergonomics -Staffing Available for Recovery Assumptions for response time:Operations normal shift complement for back shifts and weekendsoNormal Control Room Staffing6oNormal Field Staffing7One OT would be dispatched to the TDAFPTwo OTs would be dispatched to the EDGs Staffing allows for additional OTs and a Field Supervisor that would be dispatched to assist at the TDAFP and EDGs 20 20Ergonomics -Multiple PrioritiesThere would be multiple priorities during a Station Blackout (SBO) with failure of TDAFP to start:TDAFP failure to startLoss of Offsite PowerTwo Emergency Diesel Generators (EDG) failure to startECA 0.0 is designed and written to manage these priorities 21 21Ergonomics -Pump Room Conditions:Room temperature averages 90 -110 deg FNo Emergency Lighting in the room -only Emergency Lighting was in the hallwayTrip throttle valve accessibility OTs: Tour the room at least once per shiftAll carry and routinely use flashlights on roundsAre very familiar with the room layout Know how to access all areas of the roomInspect mechanical overspeed trip linkage each shift 22 22Ergonomics -Plant West Add pictures of room 23 23Ergonomics -Plant EastAdd pictures of room 24 24Ergonomics -SBO -Lighting 25 25Ergonomics -SummaryEquipment displays & controlsoControl Room indications and displays allow for quick and accurate diagnosisoProcedures and displays maintain focus on prioritiesEquipment layoutoOTs are familiar with roomoTrip Throttle Valve can be accessed from either side of the pumpInstrumentation information (quality, quantity and diversity)oControl Room information provides direct indication of trip throttle valve position (high quality)oAllows for timely diagnosisInteraction of the operator with the equipmentoOTs are familiar with the roomoOTs are trained on valve operation oValve actuator was manually operated with near normal effortEnvironmental conditionsoOTs carry a flashlightoFlashlight provides adequate lighting to access and operate oRoom is hot, but this is the normal condition and not unlike other plant areas oOTs have trained in more severe conditions 26 26Ergonomics -Risk AssessmentPSFsPSF Levels NRCCALLAWAYMultiplier Ergonomics/HMIMissing/Misleading X 50PoorX 10Nominal1 Good0.5 Poor-the design of the plant negatively impacts task performance (e.g. poor labeling, instrumentation, computer interfaces)Control room indications are clear GOODSpindle not properly lubricated, but operated with near normaleffort POORThermal overloads -Not relevant, SBO scenario

Unique valve design, however training addresses POORAccess (design) not ideal POORControl room priorities & focus is on heat sink restoration GOOD 27 27Available Time -Risk AssessmentFactors Important to Available Time

Time to S/G dryout (before core damage)Time for the crew/operator to diagnose the fail-to-start conditionTime available to act and manually start the TDAFPTime available for repeat actions 28 28Available Time -Operator Response TimingThree different crews response time tested for SBO w/loss of TDAFP All 3 crews took less than 5 minutes to reach step 4 of ECA 0.0 Dispatch an OT to the TDAFPThree different OTs were response time testedFrom the time they were contacted, given a brief of conditions, to the time they entered the room was less than 5

min These response tests validate the times used in the Callaway TimelineFollowing EOPs: 6 min[Total 6 min]Contact OT: 5 minBrief OT and Travel to the Pump Room: 5 minOT Assesses Condition: 5 minContact MCR for Instructions and receive second direction to open valve: 5 min[Total 20 min]Manipulation Time: 5 min[Total 5 min](Total Time: 31 min)[49 Minutes remain for repeated attempts to open the trip throttle valve]Total Time Available: 80 minCallaway Revised SPAR-H Timeline 29Available Time -Risk AssessmentTime to S/G dryout is 80 minutesoBased on thermodynamic heat balance for Callaway*Actual S/G secondary inventory*Decay heat based on Cycle 17 burnup conditionsoConservative assumptions*Decay heat uncertainty added

  • RCS is instantly in thermal equilibrium with S/Gs*Cycling of the Atmospheric Steam Dumps was not creditedoA significant portion of the RCS must boil away after S/G dryout for actual core damage to occur 30 30Available Time -Timeline Comparison 31 31Available Time -SummaryTime to S/G dryout (before core damage) oS/G dryout is conservatively determined to be 80 minutesTime for the crew/operator to diagnose the fail-to-start condition oControl Room diagnosis performed within 6 minutesTime available to act and manually start the TDAFP oCommunication and transit (10)
  • Contact and brief
  • Transit oAssess and manipulate (15)
  • Assess and communicate
  • ManipulationTime available for repeat actions 32 32Available Time -Risk Assessment -DiagnosesPSFsPSF Levels NRCCALLAWAYMultiplierAvailable Time -DiagnosesInadequate TimeP(failure) = 1.0Barely adequate time (~ 2/3 x nominal)10Nominal time1 Extra time (between 1 and 2 x nominal and > 30 min)

X 0.1Expansive time (> 2 x nominal and > 30 min)

X 0.01Based on Callaway's timeline, which includes an elapsed time of 6 minutes for control room diagnosis and 5 minutes to assess valve conditions, leads to a diagnosis of EXPANSIVE TIME 33 33Available Time -Risk Assessment -ActionPSFsPSF Levels NRCCALLAWAYMultiplierAvailable Time -

ActionInadequate TimeP(failure) = 1.0Time available is ~ the time required10Nominal time X 1Time available >= 5x the time required X 0.1Time available >= 50x the time required0.01Based on Callaway's timeline, which includes an elapsed time of 31 minutes for the action and 5 minutes per valve manipulation, leads to a diagnosis of TIME AVAILABLE >= 5x 34 34Risk Assessment Summary We have discussed:Procedures that establish our prioritiesIndications that maintain our focusTraining (CR and field personnel) that shape how we react to eventsStaffing that allow us to handle multiple prioritiesTiming that allows multiple attempts to open the trip throttle valveRoom conditions that with a flashlight are suitable for opening the valveWe have provided basis for:Ergonomics shaping factorAvailable Time shaping factorThese performance shaping factors lead to the risk being <1.0E-6 Very Low Risk Significance (Green)Our operating crews would open the trip throttle valve in these postulated conditions prior to the onset of core damage 35 35Hardware Corrective ActionsApproved use of a more effective high temperature grease for the trip throttle valveCorrect valve stem lubrication type and preventive maintenance frequency for other important motor operated valves are being verifiedInstalled emergency lighting in TDAFP roomInstalled an access platform for the trip throttle valveAdequate emergency lighting, access, and tooling to support other critical operator recovery actions are being verified 36 36 Process Corrective ActionsRevised work instructions for trip throttle valve replacement to verify lubrication as a critical step and made numerous other work instruction improvementsDeveloped a stand alone preventive maintenance document for trip throttle valve lubrication and changed lubrication frequencyDeveloped a more rigorous review process for preventive maintenance basis changes 37 37 Organizational Corrective ActionsContinue to reinforce written instruction use and adherenceCommunicated expectations and providing training to personnel who establish lubrication preventive maintenance bases and frequency intervalsDedicated work coordinators will be assigned for major Auxiliary Feedwater System activities during refueling outagesLowered threshold for use of Event Review Teams to investigate issues Strengthened management support for root cause analyses and associated teams 38 38 ClosingFailure of TDAFP to start is NOT ACCEPTABLEImplemented extensive corrective actions with broad extent of cause/conditionresulted in

oHardware changesoProcess changesoOrganizational behavior changesWe have a high confidence that we would have opened the trip throttle valve when neededWe ask that you consider the information we have provided today
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