IR 05000348/2011012: Difference between revisions

From kanterella
Jump to navigation Jump to search
(Created page by program invented by StriderTol)
(Created page by program invented by StriderTol)
 
(7 intermediate revisions by the same user not shown)
Line 2: Line 2:
| number = ML111960460
| number = ML111960460
| issue date = 07/15/2011
| issue date = 07/15/2011
| title = 07/12/2011-Summary of Public Meeting with Joseph M. Farley Nuclear Plant, to Discuss Safety Significance of Preliminary White Finding Associated with One Apparent Violation Documented in NRC Inspection Report 05000348-11-012 and 05000364-11
| title = Summary of Public Meeting with Joseph M. Farley Nuclear Plant, to Discuss Safety Significance of Preliminary White Finding Associated with One Apparent Violation Documented in NRC Inspection Report 05000348-11-012 and 05000364-11-012
| author name = Shaeffer S M
| author name = Shaeffer S
| author affiliation = NRC/RGN-II/DRP/RPB2
| author affiliation = NRC/RGN-II/DRP/RPB2
| addressee name = Stinson L M
| addressee name = Stinson L
| addressee affiliation = Southern Nuclear Operating Co, Inc
| addressee affiliation = Southern Nuclear Operating Co, Inc
| docket = 05000348, 05000364
| docket = 05000348, 05000364
Line 18: Line 18:


=Text=
=Text=
{{#Wiki_filter:
{{#Wiki_filter:UNITED STATES NUCLEAR REGULATORY COMMISSION uly 15, 2011
[[Issue date::July 15, 2011]]


Mr. L. Mike Stinson Vice President - Farley Southern Nuclear Operating Company, Inc.
==SUBJECT:==
 
PUBLIC MEETING SUMMARY - JOSEPH M. FARLEY NUCLEAR PLANT -
7388 North State Highway 95 Columbia, AL 36319
DOCKET NOS. 50-348 AND 50-364
 
SUBJECT: PUBLIC MEETING SUMMARY - JOSEPH M. FARLEY NUCLEAR PLANT - DOCKET NOS. 50-348 AND 50-364


==Dear Mr. Stinson:==
==Dear Mr. Stinson:==
Line 33: Line 30:
1A RCP board handswitch. This conference also addressed whether enforcement action is warranted for the associated Apparent Violation.
1A RCP board handswitch. This conference also addressed whether enforcement action is warranted for the associated Apparent Violation.


In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter will be available electronically for public inspection in the NRC Public Document Room (PDR) or from the Publicly Available Records (PARS) component of NRC's document system (ADAMS).
In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter will be available electronically for public inspection in the NRC Public Document Room (PDR) or from the Publicly Available Records (PARS) component of NRCs 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).
ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Line 39: Line 36:
Should you have any questions concerning this meeting, please contact me at (404) 997-4521.
Should you have any questions concerning this meeting, please contact me at (404) 997-4521.


Sincerely,/RA/
Sincerely,
Scott M. Shaeffer, Chief Reactor Projects Branch 2 Division of Reactor Projects Docket Nos.: 50-348, 50-364 License Nos.: NPF-2, NPF-8  
/RA/
Scott M. Shaeffer, Chief Reactor Projects Branch 2 Division of Reactor Projects Docket Nos.: 50-348, 50-364 License Nos.: NPF-2, NPF-8


===Enclosures:===
===Enclosures:===
1. List of Attendees 2. NRC Agenda 3. SNC Powerpoint Presentation  
1. List of Attendees 2. NRC Agenda 3. SNC Powerpoint Presentation
 
REGION II==
245 PEACHTREE CENTER AVENUE NE, SUITE 1200 ATLANTA, GEORGIA 30303-1257 FARLEY REGULATORY CONFERENCE Atlanta, GA July 12, 2011 Name (Print)  Title and Organization
_____________J. Munday_____________ Division Director NRC RII/DRS
_____________R. Nease ______________ _Branch Chief NRC RII/DRS/EB2_______
_____________G. McCoy______________ _Branch Chief NRC RII/DRP/RPB5______
_____________L. Suggs ______________ _Inspector NRC RII/DRS/EB2__________
_____________R. Fanner______________ _Inspector NRC RII/DRS/EB2__________
_____________G. Wiseman____________ _Senior Inspector NRC RII/DRS/EB2____
_____________D. Chung______________ NRC NRR/DRA/PRA Operational Support
_____________E. Crowe______________ _Senior Resident Farley NRC RII/DRP___
_____________W. Rogers_____________ _SRA NRC RII/DRP/RPB7_____________
_____________W. Jones______________ _Deputy Division Director NRC RII/DRP_
_____________R. Croteau_____________ _Division Director NRC RII/DRP _______
_____________L. Wert________________ Deputy Regional Administrator NRC RII_
_____________S. Sparks______________ Senior Enforcement Specialist NRC RII__
_____________S. Shaeffer____________ _Branch Chief NRC RII/DRP/RPB2______
_____________S. Rose_______________ Sr. Project Engineer NRC RII/DRP/RPB2
_____________T. Lighty______________ _Project Engineer NRC RII/DRP/RPB2__
Enclosure 1
 
UNITED STATES NUCLEAR REGULATORY COMMISSION
 
==REGION II==
245 PEACHTREE CENTER AVENUE NE, SUITE 1200 ATLANTA, GEORGIA 30303-1257 FARLEY REGULATORY CONFERENCE Atlanta, GA July 12, 2011 (Via Teleconference)
Name (Print)  Title and Organization
_____________M. Ashley___________________ NRC HQ/NRR
_____________S. Meng Wong_______________ _NRC HQ/DRA____________________________
_____________A. Klein_____________________ _NRC HQ/DRA/AFPB______________________
_____________S. Lee______________________ _NRC HQ/DRA____________________________
_____________J. Hyslop___________________ _NRC HQ/DRA/FRB_______________________
_____________N. Coleman_________________ _NRC HQ/OE_____________________________
_____________J. Circle____________________ _NRC HQ/NRR/DRA/APOB_________________
_____________R. Gallucci__________________ _NRC HQ/NRR/DRA/APLA__________________
_____________B. Martin___________________ _NRC HQ/NRR/DORL______________________
_____________D. Harrison_________________ _NRC HQ/DRA____________________________
________________________________________ _________________________________________
________________________________________ _________________________________________
________________________________________ _________________________________________
________________________________________ _________________________________________
________________________________________ _________________________________________
________________________________________ _________________________________________
Enclosure 1
 
Enclosure 1 Enclosure 2
 
REGULATORY CONFERENCE AGENDA SOUTHERN NUCLEAR OPERATING COMPANY JULY 12, 2011 NRC REGION II, ATLANTA, GEORGIA I. OPENING REMARKS AND INTRODUCTION II. NRC REGULATORY AND ENFORCEMENT POLICY III. STATEMENT OF ISSUE AND APPARENT VIOLATION IV. SOUTHERN NUCLEAR OPERATING COMPANY V. TRANSITION TO CLOSED SESSION (If Required)
a. PUBLIC QUESTIONS b. NRC REMARKS/BREAK c. SOUTHERN NUCLEAR OPERATING COMPANY VI. BREAK/NRC CAUCUS VII. NRC FOLLOW UP QUESTIONS VIII. CLOSING REMARKS IX. PUBLIC QUESTIONS (If Not Previously Performed)
Enclosure 2
 
Farley Nuclear Plant NRC Regulatory Conference July 12, 2011 Mark J Ajluni, PE Nuclear Licensing Director John D Lattner, PE Principal Engineer - Fire Protection Ken McElroy RIE Program Manager Enclosure 3
 
Agenda
* Introductions
* Objectives
* Presentation
* Wrap-Up and Conclusion Enclosure 3
 
Objectives 1. To provide new information about the event 2. To prove the handswitch fire that occurred on Nov. 10, 2010, in the Unit 1 control room was a non-challenging fire per the guidance of NUREG/CR 6850 3. To demonstrate that the event is not risk significant and should be characterized as green Enclosure 3
 
The Event
* Calibration of 1A RCP oil lift system
* Broken conduit found
* Repairs made under PM processes versus CM
* Operators later attempted start of the 1A RCP and detected burning inside the handswitch
* Operator responded by opening panel and blowing on the switch box enclosure
* At the same time the circuit opened and the burning stopped Enclosure 3
 
Enclosure 3
 
Handswitch Internals Spade Terminals Spade Terminal Region Contacts Normally Open Enclosure 3
 
Handswitch in Closed Position Contacts Closed Enclosure 3
 
Handswitch Spring Returns to Open Arcing Enclosure 3
 
Handswitch Damage Enclosure 3
 
Testing Results Because we are dealing with a specific wiring arrangement and switch all seven SNC tests of handswitch fault indicate the same location for damage and the repeatable nature of failure for this particular fault.
 
Enclosure 3
 
Handswitch Construction
* Fire resistive construction of switch block
* Does not melt or drip plastic
* Fire resistive construction of switch housing
* Objective of testing was to confirm how the switch responds to shorted conditions Enclosure 3
 
Main Control Board Handswitch Enclosure 3
 
Main Control Board Handswitch Enclosure 3
 
Main Control Board Handswitch Enclosure 3
 
Operator Intervention
* The operator action had no impact on putting out the fire
* Switch is well placed in fire retardant enclosure making direct air flow to the point of combustion impossible
* The Condition Report assumes what the operator initially believed at the time, that he blew out the fire
* Switch will self-extinguish when current path becomes interrupted
* Operator action was inconsequential, testing shows the fire will self-extinguish anyway Enclosure 3
 
Main Control Board Enclosure 3
 
No Potential for Fire Spread
* Handswitch fire self-extinguishes
* Confirmed by testing
* Handswitch fire not of sufficient duration or intensity to ignite secondary combustibles
* Test thermocouples
* CHRISTIFIRE test results
* Fire resistive properties of cables and handswitch materials
* No hot gas layer formed within panel
* Conclusion: No potential for fire spread Enclosure 3
 
NUREG/CR-6850 Appendix C Objective Classification Criteria If any one of the following exist, the event is challenging NUREG/CR-6850 Objective Criteria FNP Event A hose stream, multiple portable fire No automatic or manual suppression used extinguishers, and/or a fixed fire suppression system (either manually or automatically actuated) were used to suppress the fire One or more components outside the No evidence of any collateral damage boundaries of the fire ignition source outside of the fire ignition source were affected Combustible materials outside the No ignition of secondary combustibles boundaries of the fire ignition source were ignited Enclosure 3
 
NUREG/CR-6850 Appendix C Objective Classification Criteria If any two of the following exist, the event is challenging NUREG/CR-6850 Objective Criteria FNP Event Actuation of an automatic detection Event did not produce sufficient smoke to system  actuate the main control room detection system. An ionization smoke detector is located on the ceiling directly behind Section C of the MCB A plant trip was experienced  Event did not cause a plant trip. The unit was in cold shutdown.
 
A reported loss of greater than $5,000 Physical damage limited to the handswitch (< $1,000)
A burning duration or suppression time of Burning duration was less than two 10 minutes or longer  minutes Enclosure 3
 
NUREG/CR-6850 Appendix C Subjective Classification Criteria If any of the following exist, the event is Challenging NUREG/CR-6850 Subjective Criteria FNP Event It is apparent that active intervention was Operator blowing on the switch enclosure needed to prevent potential spread was insignificant intervention. Test data demonstrates the handswitch fire self-extinguishes There are indications that heat was No evidence of heat damage to any generated of sufficient intensity and components outside of the fire ignition duration to affect components outside source the fire ignition source There are indications that flames or heat No ignition of secondary combustibles was generated of sufficient intensity and duration to cause the ignition of secondary combustibles outside the fire ignition source Substantial smoke was generated  Insignificant amount of smoke Enclosure 3
 
NUREG/CR-6850 Appendix C Subjective Classification Criteria If any of the following exist, the event is Challenging NUREG/CR-6850 Subjective Criteria FNP Event It is apparent that active intervention was Operator blowing on the switch enclosure needed to prevent potential spread was insignificant intervention. Test data demonstrates the handswitch fire self-extinguishes There are indications that heat was No evidence of heat damage to any generated of sufficient intensity and components outside of the fire ignition duration to affect components outside source the fire ignition source There are indications that flames or heat No ignition of secondary combustibles was generated of sufficient intensity and duration to cause the ignition of secondary combustibles outside the fire ignition source Substantial smoke was generated  Insignificant amount of smoke Enclosure 3
 
NUREG/CR-6850 Appendix C Objective Classification Criteria If any two of the following exist, the event is challenging NUREG/CR-6850 Objective Criteria FNP Event Actuation of an automatic detection Event did not produce sufficient smoke to system  actuate the main control room detection system. An ionization smoke detector is located on the ceiling directly behind Section C of the MCB A plant trip was experienced  Event did not cause a plant trip. The unit was in cold shutdown.
 
A reported loss of greater than $5,000 Physical damage limited to the handswitch (< $1,000)
A burning duration or suppression time of Burning duration was less than two 10 minutes or longer  minutes Enclosure 3
 
Non-Challenging Control Room Fires From Fire Events Database Involving Intervention Fire Description  Type of Intervention Incident No 374 SDV high level RPS relay burned Control room personnel extinguished the burning relay 425 A relay burned due to its old age Portable CO2 extinguisher used 815 A relay burned up in the primary Portable CO2 extinguisher containment isolation panel used 2224 Defective insulation on windings led to Portable fire extinguisher fault within current protection relay used 2266 Small fire found in control panel Operator blew out flame transformer Enclosure 3
 
Conclusion: Non-Challenging
* None of the objective or subjective criteria was met
* Event is non-challenging Enclosure 3
 
SNC Risk Significance Determination Enclosure 3


cc w/encls: (See page 2)
SDP Factors HRA Control Room Abandonment Dominated Unit 1 MCR Panel (Unit 2)
July 15, 2011 Mr. L. Mike Stinson Vice President - Farley Southern Nuclear Operating Company, Inc.
Suppression  Non-Fire Ignition Will Fire before Fire Severity  Shutdown propagation to Suppression Probability Propagate?  Factor  outside MCR cable bundle  Probability No Risk Not Significant    Unit 2 Enclosure 3


7388 North State Highway 95 Columbia, AL 36319
Phase III Summary Fire Propagation Suppress before MCR Shutdown CCDP Ignition Probability propagation to Abandonment outside Probability  cable bundle Probability MCR NRC 1.0 0.5 1.0** 1.1E-3 (upper) 9.9E-3 5.5E-6 (white)
5.6E-4 (lower) 2.8E-6 (white)
SNC 1.0 0.5* 1.0** (upper) 6.3E-5 3.1E-3 1.0E-7 (green)
0.01 (realistic) 6.4E-4  1.0E-8 (green)
** SNC Position - fire not challenging
***Considered in MCR abandonment probability Enclosure 3


SUBJECT: PUBLIC MEETING SUMMARY - JOSEPH M. FARLEY NUCLEAR PLANT - DOCKET NOS. 50-348 AND 50-364
MCR Abandonment - HVAC
* HVAC Operation
- HVAC allows Main Control Room (MCR) to remain manned for larger fires
- Larger fires are less likely to occur
- Risk of Abandonment reduced by a factor of 20
* Both NRC and SNC used NUREG/CR-6850 methods Enclosure 3


==Dear Mr. Stinson:==
MCR Abandonment (cont.)
This refers to the Regulatory Conference conducted on July 12, 2011, in Atlanta, GA. The purpose of the Regulatory Conference was to provide opportunities to discuss the safety significance of the preliminary White finding associated with one Apparent Violation that was documented in NRC Inspection Report 05000348/2011012 and 364/2011012 (ML111590912).


The findings dealt with the failure to maintain the configuration of the 1A reactor coolant pump (RCP) oil lift pump system in accordance with plant design and drawings. This resulted in an electrical short on November 10, 2010, that caused a fire on the Unit 1 main control room (MCR) 1A RCP board handswitch. This conference also addressed whether enforcement action is warranted for the associated Apparent Violation.
* NRC assumed HVAC inoperable
* SNC determined HVAC was operating normally and would continue to operate
* HVAC controls/circuitry physically separated from fire location
* Operators and Fire Brigade would not trip HVAC Enclosure 3


In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter will be available electronically for public inspection in the NRC Public Document Room (PDR) or from the Publicly Available Records (PARS) component of NRC's document system (ADAMS).
Farley Common MCR Fire Location HVAC Controls Enclosure 3


ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Shutdown from Outside MCR NRC Value SNC Value Comments 9.9E-3 3.1E-3 *Dominated by loss of aux feedwater due to human error
  *Equipment failure of AFW negligible
  *Difference is due to modeling of human error Enclosure 3


Should you have any questions concerning this meeting, please contact me at (404) 997-4521.
SDP Summary
* Even assuming a challenging fire and an event probability of 1.0, the CCDP is green
- HVAC was a operating normally making the likelihood of control room evacuation less
- SNC performed a more realistic HRA reducing the calculated risk Enclosure 3


Sincerely,/RA/ Scott M. Shaeffer, Chief Reactor Projects Branch 2 Division of Reactor Projects Docket Nos.: 50-348, 50-364 License Nos.: NPF-2, NPF-8
Corrective Actions Enclosure 3


===Enclosures:===
Root Cause of the Event
1. List of Attendees 2. NRC Agenda 3. SNC Powerpoint Presentation
* No written work package generated for the replacement of the flex conduit. We stepped out of process mixing CM with PM
* No lift sheet
* No pre-job brief
* Management has not been successful in getting Maintenance to internalize Human Performance tool usage 100% of the time.


cc w/encls: (See page 2) X PUBLICLY AVAILABLE G NON-PUBLICLY AVAILABLE G SENSITIVE X NON-SENSITIVE ADAMS: XG Yes ACCESSION NUMBER:_____ML111960460________ X G SUNSI REVIEW COMPLETE OFFICE RII:DRP RII:DRP SIGNATURE SMS /RA for/ SMS /RA/ NAME SRose SShaeffer DATE 07/15/2011 07/15/2011 E-MAIL COPY? YES NO YES NO YES NO YES NO YES NO YES NO YES NO OFFICIAL RECORD COPY DOCUMENT NAME: G:\DRPII\RPB2\FARLEY\MEETINGS\MEETING SUMMARY 071211.DOCX SNC 2 cc w/encl: B. D. McKinney, Jr. Regulatory Response Manager Southern Nuclear Operating Company, Inc.
* No discussion of human performance tools when problem identified
* Skill-of-the-craft is accepted behavior Enclosure 3


Electronic Mail Distribution M. J. Ajluni Nuclear Licensing Director Southern Nuclear Operating Company, Inc.
Corrective Actions
* Revised fleet procedures to define allowable work scope for minor maintenance, tool pouch work, and CR initiation.


Electronic Mail Distribution T. D. Honeycutt Regulatory Response Supervisor Southern Nuclear Operating Company, Inc. Electronic Mail Distribution Todd L. Youngblood Plant Manager Joseph M. Farley Nuclear Plant Electronic Mail Distribution L. P. Hill Licensing Supervisor Southern Nuclear Operating Company, Inc. Electronic Mail Distribution Jeffrey T. Gasser Chief Nuclear Officer Southern Nuclear Operating Company, Inc. Electronic Mail Distribution R. L. Gladney Licensing Engineer Southern Nuclear Operating Company, Inc. Electronic Mail Distribution N. J. Stringfellow Licensing Manager Southern Nuclear Operating Company, Inc. Electronic Mail Distribution Paula Marino Vice President Engineering Southern Nuclear Operating Company, Inc. Electronic Mail Distribution J. L. Pemberton SVP & General Counsel-Ops & SNC Southern Nuclear Operating Company, Inc. Electronic Mail Distribution Chris Clark Commissioner Georgia Department of Natural Resources Electronic Mail Distribution John G. Horn Site Support Manager Joseph M. Farley Nuclear Plant Southern Nuclear Operating Company, Inc. Electronic Mail Distribution Ted V. Jackson Emergency Response and Radiation Program Manager Environmental Protection Division Georgia Department of Natural Resources Electronic Mail Distribution Tom W. Pelham Performance Improvement Supervisor Joseph M. Farley Nuclear Plant Southern Nuclear Operating Company, Inc. Electronic Mail Distribution Cynthia A. Sanders Radioactive Materials Program Manager Environmental Protection Division Georgia Department of Natural Resources Electronic Mail Distribution James C. Hardeman Environmental Radiation Program Manager Environmental Protection Division Georgia Department of Natural Resources Electronic Mail Distribution William D. Oldfield Principal Licensing Engineer Joseph M. Farley Nuclear Plant Electronic Mail Distribution (cc w/encl continued next page)
* Maintenance personnel were trained using dynamic training methods.


SNC 3 (cc w/encl continued) Mr. Mark Culver Chairman Houston County Commission P. O. Box 6406 Dothan, AL 36302 James A. Sommerville Program Coordination Branch Chief Environmental Protection Division Georgia Department of Natural Resources Electronic Mail Distribution James L. McNees, CHP Director Office of Radiation Control Alabama Dept. of Public Health P. O. Box 303017 Montgomery, AL 36130-3017 State Health Officer Alabama Dept. of Public Health RSA Tower - Administration Suite 1552 P.O. Box 30317 Montgomery, AL 36130-3017 L. L. Crumpton Administrative Assistant, Sr. Southern Nuclear Operating Company, Inc.
* Implemented leadership action plan for Maintenance Superintendents. Accomplished with the assistance of leadership expert.


Electronic Mail Distribution F. Allen Barnes Director Environmental Protection Division Georgia Department of Natural Resources Electronic Mail Distribution SNC 4 Letter to L. Mike Stinson from Scott M. Shaeffer dated July 15, 2011
Enclosure 3


SUBJECT: PUBLIC MEETING SUMMARY - JOSEPH M. FARLEY NUCLEAR PLANT - DOCKET NOS. 50-348 AND 50-364 Distribution w/encls: RidsNrrPMFarley Resource C. Evans, RII EICS L. Douglas, RII EICS OE Mail RIDSNRRDIRS PUBLIC Enclosure 1 FARLEY REGULATORY CONFERENCE Atlanta, GA July 12, 2011 Name (Print)
Conclusion and Wrap-Up
_____________J. Munday_____________ _____________R. Nease ______________
* The event is non-challenging as it does not meet the NUREG / CR 6850 criteria for challenging
_____________G. McCoy______________ _____________L. Suggs ______________ _____________R. Fanner______________ _____________G. Wiseman____________ _____________D. Chung______________
* Tests revealed that the handswitch consistently fails at the same location, resulting in a self-extinguishing condition
_____________E. Crowe______________ _____________W. Rogers_____________ _____________W. Jones______________ _____________R. Croteau_____________ _____________L. Wert________________
* Target cables will not catch fire because heat rates are low.
_____________S. Sparks______________ _____________S. Shaeffer____________ _____________S. Rose_______________ _____________T. Lighty______________ Title and Organization Division Director NRC RII/DRS _Branch Chief NRC RII/DRS/EB2_______ _Branch Chief NRC RII/DRP/RPB5______ _Inspector NRC RII/DRS/EB2__________ _Inspector NRC RII/DRS/EB2__________ _Senior Inspector NRC RII/DRS/EB2____
NRC NRR/DRA/PRA Operational Support _Senior Resident Farley NRC RII/DRP___ _SRA NRC RII/DRP/RPB7_____________ _Deputy Division Director NRC RII/DRP_ _Division Director NRC RII/DRP _______
Deputy Regional Administrator NRC RII_ Senior Enforcement Specialist NRC RII__ _Branch Chief NRC RII/DRP/RPB2______ Sr. Project Engineer NRC RII/DRP/RPB2 _Project Engineer NRC RII/DRP/RPB2__
Enclosure 1 FARLEY REGULATORY CONFERENCE Atlanta, GA July 12, 2011 (Via Teleconference) Name (Print) _____________M. Ashley___________________
_____________S. Meng Wong_______________ _____________A. Klein_____________________ _____________S. Lee______________________ _____________J. Hyslop___________________ _____________N. Coleman_________________
_____________J. Circle____________________ _____________R. Gallucci__________________ _____________B. Martin___________________ _____________D. Harrison_________________ ________________________________________
________________________________________ ________________________________________ ________________________________________ ________________________________________ ________________________________________ Title and Organization NRC HQ/NRR _NRC HQ/DRA____________________________ _NRC HQ/DRA/AFPB______________________ _NRC HQ/DRA____________________________ _NRC HQ/DRA/FRB_______________________
_NRC HQ/OE_____________________________ _NRC HQ/NRR/DRA/APOB_________________ _NRC HQ/NRR/DRA/APLA__________________ _NRC HQ/NRR/DORL______________________ _NRC HQ/DRA____________________________
_________________________________________ _________________________________________ _________________________________________ _________________________________________ _________________________________________ _________________________________________
Enclosure 1 Enclosure 2 2 Enclosure 2 REGULATORY CONFERENCE AGENDASOUTHERN NUCLEAR OPERATING COMPANYJULY 12, 2011NRC REGION II, ATLANTA, GEORGIAI.OPENING REMARKS AND INTRODUCTION II. NRC REGULATORY AND ENFORCEMENT POLICY III. STATEMENT OF ISSUE AND APPARENT VIOLATION IV. SOUTHERN NUCLEAR OPERATING COMPANY V. TRANSITION TO CLOSED SESSION (If Required)a. PUBLIC QUESTIONSb. NRC REMARKS/BREAKc. SOUTHERN NUCLEAR OPERATING COMPANYVI. BREAK/NRC CAUCUS VII. NRC FOLLOW UP QUESTIONS VIII. CLOSING REMARKS IX. PUBLIC QUESTIONS (If Not Previously Performed)
Enclosure 3 Farley Nuclear Plant NRC Regulatory Conference July 12, 2011Mark J Ajluni, PE Nuclear Licensing DirectorJohn D Lattner, PEPrincipal Engineer -Fire ProtectionKen McElroy RIE Program Manager 2 Enclosure 3 Agenda*Introductions*Objectives*Presentation*Wrap-Up and Conclusion 3 Enclosure 3 Objectives 1.To provide new information about the event2.To prove the handswitch fire that occurred on Nov. 10, 2010, in the Unit 1 control room was a non-challengingfire per the guidance of NUREG/CR 68503.To demonstrate that the event is not risk significantand should be characterized as green 4 Enclosure 3 The Event*Calibration of 1A RCP oil lift system*Broken conduit found*Repairs made under PM processes versus CM*Operators later attempted start of the 1A RCP and detected burning inside the handswitch*Operator responded by opening panel and blowing on the switch box enclosure *At the same time the circuit opened and the burning stopped 5 Enclosure 3 6 Enclosure 3 Handswitch InternalsSpade TerminalsSpade Terminal RegionContacts NormallyOpen 7 Enclosure 3 Handswitch in Closed PositionContacts Closed 8 Enclosure 3 Handswitch Spring Returns to OpenArcing 9 Enclosure 3 Handswitch Damage 10 Enclosure 3 Testing ResultsBecause we are dealing with a specific wiring arrangement and switch all seven SNC tests of handswitch fault indicate the same location for damage and the repeatable nature of failure for this particular fault.


11 Enclosure 3 Handswitch Construction*Fire resistive construction of switch block*Does not melt or drip plastic*Fire resistive construction of switch housing*Objective of testing was to confirm how the switch responds to shorted conditions 12 Enclosure 3 Main Control Board Handswitch 13 Enclosure 3 Main Control Board Handswitch 14 Enclosure 3 Main Control Board Handswitch 15 Enclosure 3 Operator Intervention *The operator action had no impact on putting out the fire *Switch is well placed in fire retardant enclosure making direct air flow to the point of combustion impossible*The Condition Report assumes what the operator initially believed at the time, that he blew out the fire*Switch will self-extinguish when current path becomes interrupted *Operator action was inconsequential, testing shows the fire will self-extinguish anyway 16 Enclosure 3 Main Control Board 17 Enclosure 3 No Potential for Fire Spread*Handswitchfire self-extinguishes*Confirmed by testing*Handswitchfire not of sufficient duration or intensity to ignite secondary combustibles*Test thermocouples*CHRISTIFIRE test results*Fire resistive properties of cables and handswitchmaterials*No hot gas layer formed within panel*Conclusion: No potential for fire spread 18 Enclosure 3 NUREG/CR-6850 Appendix C Objective Classification CriteriaNUREG/CR-6850 Objective CriteriaFNP EventA hose stream, multiple portable fire extinguishers, and/or a fixed fire suppression system (either manually or automatically actuated) were used to suppress the fireNo automatic or manual suppression usedOne or more components outside the boundaries of the fire ignition source were affectedNo evidence of anycollateral damage outside of the fire ignition sourceCombustible materials outside the boundaries of thefire ignition source were ignitedNo ignition of secondary combustiblesIf any one of the following exist, the event is challenging 19 Enclosure 3 NUREG/CR-6850 Appendix C Objective Classification CriteriaNUREG/CR-6850 Objective CriteriaFNP EventActuation of an automatic detection system Event did notproduce sufficient smoke to actuate the main control room detection system. An ionization smoke detector is located on the ceiling directly behind Section C of the MCBA plant trip was experiencedEventdid not cause a plant trip. The unit was in cold shutdown.A reported loss of greater than $5,000Physical damage limited to the handswitch (< $1,000)A burning duration or suppression time of10 minutes or longerBurning duration was less than two minutesIf any two of the following exist, the event is challenging 20 Enclosure 3 NUREG/CR-6850 Appendix C Subjective Classification CriteriaNUREG/CR-6850 Subjective CriteriaFNP EventIt is apparent that active interventionwas needed to prevent potential spreadOperator blowingon the switch enclosure was insignificant intervention. Test data demonstrates the handswitchfire self-
* Modeling control room HVAC results in green risk.
extinguishesThere are indications that heat was generated of sufficient intensity and duration to affect components outside the fire ignition sourceNo evidence of heat damageto any components outside of the fire ignition sourceThere are indications that flames or heat was generated of sufficientintensity and duration to cause the ignition of secondary combustibles outside the fire ignition sourceNo ignition of secondary combustiblesSubstantial smoke was generatedInsignificant amount of smoke If any of the following exist, the event is Challenging 21 Enclosure 3 NUREG/CR-6850 Appendix C Subjective Classification CriteriaNUREG/CR-6850 Subjective CriteriaFNP EventIt is apparent that active interventionwas needed to prevent potential spreadOperator blowingon the switch enclosure was insignificant intervention. Test data demonstrates the handswitchfire self-
extinguishesThere are indications that heat was generated of sufficient intensity and duration to affect components outside the fire ignition sourceNo evidence of heat damageto any components outside of the fire ignition sourceThere are indications that flames or heat was generated of sufficientintensity and duration to cause the ignition of secondary combustibles outside the fire ignition sourceNo ignition of secondary combustiblesSubstantial smoke was generatedInsignificant amount of smoke If any of the following exist, the event is Challenging 22 Enclosure 3 NUREG/CR-6850 Appendix C Objective Classification CriteriaNUREG/CR-6850 Objective CriteriaFNP EventActuation of an automatic detection system Event did notproduce sufficient smoke to actuate the main control room detection system. An ionization smoke detector is located on the ceiling directly behind Section C of the MCBA plant trip was experiencedEventdid not cause a plant trip. The unit was in cold shutdown.A reported loss of greater than $5,000Physical damage limited to the handswitch (< $1,000)A burning duration or suppression time of10 minutes or longerBurning duration was less than two minutesIf any two of the following exist, the event is challenging 23 Enclosure 3 Non-Challenging Control Room Fires From Fire Events Database Involving InterventionFire IncidentNoDescriptionType of Intervention374SDV high level RPS relay burnedControl room personnel extinguishedthe burning relay425A relay burned due to its "old age"Portable CO2extinguisherused815A relay burned up in the primary containment isolation panelPortable CO2extinguisher used2224Defective insulation on windingsled to fault within current protection relayPortablefire extinguisher used2266Small fire found in control panel transformerOperator blew out flame 24 Enclosure 3 Conclusion: Non-Challenging*None of the objective or subjective criteria was met*Event is non-challenging 25 Enclosure 3 SNC Risk Significance Determination 26 Enclosure 3 Fire Ignition ProbabilityWill Fire Propagate?Fire Severity FactorNon-Suppression ProbabilityShutdown outside MCRRisk Not SignificantNoControl Room AbandonmentSDP FactorsHRA Dominated(Unit 2)Suppression before propagation to cable bundle Unit 1 MCR PanelUnit 2 27 Enclosure 3 Phase III SummaryFire IgnitionProbabilityPropagation ProbabilitySuppress before propagationto cable bundleMCR Abandonment ProbabilityShutdown outside MCRCCDPNRC1.00.51.0**1.1E-3 (upper)5.6E-4 (lower)9.9E-35.5E-6 (white)2.8E-6 (white)SNC1.00.5*1.0** (upper)0.01 (realistic)6.3E-56.4E-43.1E-31.0E-7 (green)1.0E-8 (green)** SNC Position -fire not challenging***Considered in MCR abandonment probability 28 Enclosure 3 MCR Abandonment -HVAC*HVAC Operation-HVAC allows Main Control Room (MCR) to remain manned for larger fires-Larger fires are less likely to occur-Risk of Abandonment reduced by a factor of 20*Both NRC and SNC used NUREG/CR-6850 methods 29 Enclosure 3 MCR Abandonment (cont.)*NRC assumed HVAC inoperable *SNC determined HVAC was operating normally and would continue to operate*HVAC controls/circuitry physically separated from fire location*Operators and Fire Brigade would not trip HVAC 30 Enclosure 3 Farley Common MCRFire LocationHVAC Controls 31 Enclosure 3 Shutdown from Outside MCRNRC ValueSNC ValueComments9.9E-33.1E-3*Dominatedby loss of aux feedwater due to human error*Equipment failure of AFW negligible*Difference is due to modeling of human error 32 Enclosure 3 SDP Summary*Even assuming a "challenging" fire and an event probability of 1.0, the CCDP is green-HVAC was a operating normally making the likelihood of control room evacuation less-SNC performed a more realistic HRA reducing the calculated risk 33 Enclosure 3 Corrective Actions 34 Enclosure 3 Root Cause of the Event*No written work package generated for the replacement of the flex conduit. We stepped out of process mixing CM with PM*No lift sheet*No pre-job brief*Management has not been successful in getting Maintenance to internalize Human Performance tool usage 100% of the time.*No discussion of human performance tools when problem identified *Skill-of-the-craft is accepted behavior 35 Enclosure 3 Corrective Actions*Revised fleet procedures to define allowable work scope for minor maintenance, tool pouch work, and CR initiation.*Maintenance personnel were trained using dynamic training methods.*Implemented leadership action plan for Maintenance Superintendents. Accomplished with the assistance of leadership expert.


36 Enclosure 3 Conclusion and Wrap-Up*The event is non-challenging as it does not meet the NUREG / CR 6850 criteria for challenging*Tests revealed that the handswitch consistently fails at the same location, resulting in a self-extinguishing condition*Target cables will not catch fire because heat rates are low.*Modeling control room HVAC results in "green " risk.*The event is not risk significant*The event should be characterized as green
* The event is not risk significant
* The event should be characterized as green Enclosure 3
}}
}}

Latest revision as of 03:57, 6 December 2019

Summary of Public Meeting with Joseph M. Farley Nuclear Plant, to Discuss Safety Significance of Preliminary White Finding Associated with One Apparent Violation Documented in NRC Inspection Report 05000348-11-012 and 05000364-11-012
ML111960460
Person / Time
Site: Farley  Southern Nuclear icon.png
Issue date: 07/15/2011
From: Scott Shaeffer
NRC/RGN-II/DRP/RPB2
To: Stinson L
Southern Nuclear Operating Co
References
IR-11-012
Download: ML111960460 (46)
v • d • e


Text

UNITED STATES NUCLEAR REGULATORY COMMISSION uly 15, 2011

SUBJECT:

PUBLIC MEETING SUMMARY - JOSEPH M. FARLEY NUCLEAR PLANT -

DOCKET NOS. 50-348 AND 50-364

Dear Mr. Stinson:

This refers to the Regulatory Conference conducted on July 12, 2011, in Atlanta, GA. The purpose of the Regulatory Conference was to provide opportunities to discuss the safety significance of the preliminary White finding associated with one Apparent Violation that was documented in NRC Inspection Report 05000348/2011012 and 364/2011012 (ML111590912).

The findings dealt with the failure to maintain the configuration of the 1A reactor coolant pump (RCP) oil lift pump system in accordance with plant design and drawings. This resulted in an electrical short on November 10, 2010 that caused a fire on the Unit 1 main control room (MCR)

1A RCP board handswitch. This conference also addressed whether enforcement action is warranted for the associated Apparent Violation.

In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter will be available electronically for public inspection in the NRC Public Document Room (PDR) or from the Publicly Available Records (PARS) component of NRCs 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 meeting, please contact me at (404) 997-4521.

Sincerely,

/RA/

Scott M. Shaeffer, Chief Reactor Projects Branch 2 Division of Reactor Projects Docket Nos.: 50-348, 50-364 License Nos.: NPF-2, NPF-8

Enclosures:

1. List of Attendees 2. NRC Agenda 3. SNC Powerpoint Presentation

REGION II==

245 PEACHTREE CENTER AVENUE NE, SUITE 1200 ATLANTA, GEORGIA 30303-1257 FARLEY REGULATORY CONFERENCE Atlanta, GA July 12, 2011 Name (Print) Title and Organization

_____________J. Munday_____________ Division Director NRC RII/DRS

_____________R. Nease ______________ _Branch Chief NRC RII/DRS/EB2_______

_____________G. McCoy______________ _Branch Chief NRC RII/DRP/RPB5______

_____________L. Suggs ______________ _Inspector NRC RII/DRS/EB2__________

_____________R. Fanner______________ _Inspector NRC RII/DRS/EB2__________

_____________G. Wiseman____________ _Senior Inspector NRC RII/DRS/EB2____

_____________D. Chung______________ NRC NRR/DRA/PRA Operational Support

_____________E. Crowe______________ _Senior Resident Farley NRC RII/DRP___

_____________W. Rogers_____________ _SRA NRC RII/DRP/RPB7_____________

_____________W. Jones______________ _Deputy Division Director NRC RII/DRP_

_____________R. Croteau_____________ _Division Director NRC RII/DRP _______

_____________L. Wert________________ Deputy Regional Administrator NRC RII_

_____________S. Sparks______________ Senior Enforcement Specialist NRC RII__

_____________S. Shaeffer____________ _Branch Chief NRC RII/DRP/RPB2______

_____________S. Rose_______________ Sr. Project Engineer NRC RII/DRP/RPB2

_____________T. Lighty______________ _Project Engineer NRC RII/DRP/RPB2__

Enclosure 1

UNITED STATES NUCLEAR REGULATORY COMMISSION

REGION II

245 PEACHTREE CENTER AVENUE NE, SUITE 1200 ATLANTA, GEORGIA 30303-1257 FARLEY REGULATORY CONFERENCE Atlanta, GA July 12, 2011 (Via Teleconference)

Name (Print) Title and Organization

_____________M. Ashley___________________ NRC HQ/NRR

_____________S. Meng Wong_______________ _NRC HQ/DRA____________________________

_____________A. Klein_____________________ _NRC HQ/DRA/AFPB______________________

_____________S. Lee______________________ _NRC HQ/DRA____________________________

_____________J. Hyslop___________________ _NRC HQ/DRA/FRB_______________________

_____________N. Coleman_________________ _NRC HQ/OE_____________________________

_____________J. Circle____________________ _NRC HQ/NRR/DRA/APOB_________________

_____________R. Gallucci__________________ _NRC HQ/NRR/DRA/APLA__________________

_____________B. Martin___________________ _NRC HQ/NRR/DORL______________________

_____________D. Harrison_________________ _NRC HQ/DRA____________________________

________________________________________ _________________________________________

________________________________________ _________________________________________

________________________________________ _________________________________________

________________________________________ _________________________________________

________________________________________ _________________________________________

________________________________________ _________________________________________

Enclosure 1

Enclosure 1 Enclosure 2

REGULATORY CONFERENCE AGENDA SOUTHERN NUCLEAR OPERATING COMPANY JULY 12, 2011 NRC REGION II, ATLANTA, GEORGIA I. OPENING REMARKS AND INTRODUCTION II. NRC REGULATORY AND ENFORCEMENT POLICY III. STATEMENT OF ISSUE AND APPARENT VIOLATION IV. SOUTHERN NUCLEAR OPERATING COMPANY V. TRANSITION TO CLOSED SESSION (If Required)

a. PUBLIC QUESTIONS b. NRC REMARKS/BREAK c. SOUTHERN NUCLEAR OPERATING COMPANY VI. BREAK/NRC CAUCUS VII. NRC FOLLOW UP QUESTIONS VIII. CLOSING REMARKS IX. PUBLIC QUESTIONS (If Not Previously Performed)

Enclosure 2

Farley Nuclear Plant NRC Regulatory Conference July 12, 2011 Mark J Ajluni, PE Nuclear Licensing Director John D Lattner, PE Principal Engineer - Fire Protection Ken McElroy RIE Program Manager Enclosure 3

Agenda

  • Introductions
  • Objectives
  • Presentation
  • Wrap-Up and Conclusion Enclosure 3

Objectives 1. To provide new information about the event 2. To prove the handswitch fire that occurred on Nov. 10, 2010, in the Unit 1 control room was a non-challenging fire per the guidance of NUREG/CR 6850 3. To demonstrate that the event is not risk significant and should be characterized as green Enclosure 3

The Event

  • Calibration of 1A RCP oil lift system
  • Broken conduit found
  • Repairs made under PM processes versus CM
  • Operators later attempted start of the 1A RCP and detected burning inside the handswitch
  • Operator responded by opening panel and blowing on the switch box enclosure
  • At the same time the circuit opened and the burning stopped Enclosure 3

Enclosure 3

Handswitch Internals Spade Terminals Spade Terminal Region Contacts Normally Open Enclosure 3

Handswitch in Closed Position Contacts Closed Enclosure 3

Handswitch Spring Returns to Open Arcing Enclosure 3

Handswitch Damage Enclosure 3

Testing Results Because we are dealing with a specific wiring arrangement and switch all seven SNC tests of handswitch fault indicate the same location for damage and the repeatable nature of failure for this particular fault.

Enclosure 3

Handswitch Construction

  • Fire resistive construction of switch block
  • Does not melt or drip plastic
  • Fire resistive construction of switch housing
  • Objective of testing was to confirm how the switch responds to shorted conditions Enclosure 3

Main Control Board Handswitch Enclosure 3

Main Control Board Handswitch Enclosure 3

Main Control Board Handswitch Enclosure 3

Operator Intervention

  • The operator action had no impact on putting out the fire
  • Switch is well placed in fire retardant enclosure making direct air flow to the point of combustion impossible
  • The Condition Report assumes what the operator initially believed at the time, that he blew out the fire
  • Switch will self-extinguish when current path becomes interrupted
  • Operator action was inconsequential, testing shows the fire will self-extinguish anyway Enclosure 3

Main Control Board Enclosure 3

No Potential for Fire Spread

  • Handswitch fire self-extinguishes
  • Confirmed by testing
  • Handswitch fire not of sufficient duration or intensity to ignite secondary combustibles
  • Test thermocouples
  • CHRISTIFIRE test results
  • Fire resistive properties of cables and handswitch materials
  • No hot gas layer formed within panel
  • Conclusion: No potential for fire spread Enclosure 3

NUREG/CR-6850 Appendix C Objective Classification Criteria If any one of the following exist, the event is challenging NUREG/CR-6850 Objective Criteria FNP Event A hose stream, multiple portable fire No automatic or manual suppression used extinguishers, and/or a fixed fire suppression system (either manually or automatically actuated) were used to suppress the fire One or more components outside the No evidence of any collateral damage boundaries of the fire ignition source outside of the fire ignition source were affected Combustible materials outside the No ignition of secondary combustibles boundaries of the fire ignition source were ignited Enclosure 3

NUREG/CR-6850 Appendix C Objective Classification Criteria If any two of the following exist, the event is challenging NUREG/CR-6850 Objective Criteria FNP Event Actuation of an automatic detection Event did not produce sufficient smoke to system actuate the main control room detection system. An ionization smoke detector is located on the ceiling directly behind Section C of the MCB A plant trip was experienced Event did not cause a plant trip. The unit was in cold shutdown.

A reported loss of greater than $5,000 Physical damage limited to the handswitch (< $1,000)

A burning duration or suppression time of Burning duration was less than two 10 minutes or longer minutes Enclosure 3

NUREG/CR-6850 Appendix C Subjective Classification Criteria If any of the following exist, the event is Challenging NUREG/CR-6850 Subjective Criteria FNP Event It is apparent that active intervention was Operator blowing on the switch enclosure needed to prevent potential spread was insignificant intervention. Test data demonstrates the handswitch fire self-extinguishes There are indications that heat was No evidence of heat damage to any generated of sufficient intensity and components outside of the fire ignition duration to affect components outside source the fire ignition source There are indications that flames or heat No ignition of secondary combustibles was generated of sufficient intensity and duration to cause the ignition of secondary combustibles outside the fire ignition source Substantial smoke was generated Insignificant amount of smoke Enclosure 3

NUREG/CR-6850 Appendix C Subjective Classification Criteria If any of the following exist, the event is Challenging NUREG/CR-6850 Subjective Criteria FNP Event It is apparent that active intervention was Operator blowing on the switch enclosure needed to prevent potential spread was insignificant intervention. Test data demonstrates the handswitch fire self-extinguishes There are indications that heat was No evidence of heat damage to any generated of sufficient intensity and components outside of the fire ignition duration to affect components outside source the fire ignition source There are indications that flames or heat No ignition of secondary combustibles was generated of sufficient intensity and duration to cause the ignition of secondary combustibles outside the fire ignition source Substantial smoke was generated Insignificant amount of smoke Enclosure 3

NUREG/CR-6850 Appendix C Objective Classification Criteria If any two of the following exist, the event is challenging NUREG/CR-6850 Objective Criteria FNP Event Actuation of an automatic detection Event did not produce sufficient smoke to system actuate the main control room detection system. An ionization smoke detector is located on the ceiling directly behind Section C of the MCB A plant trip was experienced Event did not cause a plant trip. The unit was in cold shutdown.

A reported loss of greater than $5,000 Physical damage limited to the handswitch (< $1,000)

A burning duration or suppression time of Burning duration was less than two 10 minutes or longer minutes Enclosure 3

Non-Challenging Control Room Fires From Fire Events Database Involving Intervention Fire Description Type of Intervention Incident No 374 SDV high level RPS relay burned Control room personnel extinguished the burning relay 425 A relay burned due to its old age Portable CO2 extinguisher used 815 A relay burned up in the primary Portable CO2 extinguisher containment isolation panel used 2224 Defective insulation on windings led to Portable fire extinguisher fault within current protection relay used 2266 Small fire found in control panel Operator blew out flame transformer Enclosure 3

Conclusion: Non-Challenging

  • None of the objective or subjective criteria was met
  • Event is non-challenging Enclosure 3

SNC Risk Significance Determination Enclosure 3

SDP Factors HRA Control Room Abandonment Dominated Unit 1 MCR Panel (Unit 2)

Suppression Non-Fire Ignition Will Fire before Fire Severity Shutdown propagation to Suppression Probability Propagate? Factor outside MCR cable bundle Probability No Risk Not Significant Unit 2 Enclosure 3

Phase III Summary Fire Propagation Suppress before MCR Shutdown CCDP Ignition Probability propagation to Abandonment outside Probability cable bundle Probability MCR NRC 1.0 0.5 1.0** 1.1E-3 (upper) 9.9E-3 5.5E-6 (white)

5.6E-4 (lower) 2.8E-6 (white)

SNC 1.0 0.5* 1.0** (upper) 6.3E-5 3.1E-3 1.0E-7 (green)

0.01 (realistic) 6.4E-4 1.0E-8 (green)

    • SNC Position - fire not challenging
      • Considered in MCR abandonment probability Enclosure 3

MCR Abandonment - HVAC

- HVAC allows Main Control Room (MCR) to remain manned for larger fires

- Larger fires are less likely to occur

- Risk of Abandonment reduced by a factor of 20

MCR Abandonment (cont.)

  • SNC determined HVAC was operating normally and would continue to operate
  • HVAC controls/circuitry physically separated from fire location
  • Operators and Fire Brigade would not trip HVAC Enclosure 3

Farley Common MCR Fire Location HVAC Controls Enclosure 3

Shutdown from Outside MCR NRC Value SNC Value Comments 9.9E-3 3.1E-3 *Dominated by loss of aux feedwater due to human error

  • Equipment failure of AFW negligible
  • Difference is due to modeling of human error Enclosure 3

SDP Summary

  • Even assuming a challenging fire and an event probability of 1.0, the CCDP is green

- HVAC was a operating normally making the likelihood of control room evacuation less

- SNC performed a more realistic HRA reducing the calculated risk Enclosure 3

Corrective Actions Enclosure 3

Root Cause of the Event

  • No written work package generated for the replacement of the flex conduit. We stepped out of process mixing CM with PM
  • No lift sheet
  • No pre-job brief
  • Management has not been successful in getting Maintenance to internalize Human Performance tool usage 100% of the time.
  • No discussion of human performance tools when problem identified
  • Skill-of-the-craft is accepted behavior Enclosure 3

Corrective Actions

  • Revised fleet procedures to define allowable work scope for minor maintenance, tool pouch work, and CR initiation.
  • Maintenance personnel were trained using dynamic training methods.
  • Implemented leadership action plan for Maintenance Superintendents. Accomplished with the assistance of leadership expert.

Enclosure 3

Conclusion and Wrap-Up

  • The event is non-challenging as it does not meet the NUREG / CR 6850 criteria for challenging
  • Tests revealed that the handswitch consistently fails at the same location, resulting in a self-extinguishing condition
  • Target cables will not catch fire because heat rates are low.
  • Modeling control room HVAC results in green risk.
  • The event is not risk significant
  • The event should be characterized as green Enclosure 3
Retrieved from "https://kanterella.com/w/index.php?title=IR_05000348/2011012&oldid=2240867"