ML13100A359

Wolf Creek, Response to RAI Regarding License Amendment Request for Deviation from Fire Protection Program Requirements for Volume Control Tank Outlet Valves

ML13100A359
Person / Time
Site:	Wolf Creek
Issue date:	03/20/2013
From:	Broschak J P Wolf Creek
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
ET 13-0011, TAC ME9823
Download: ML13100A359 (7)

Text

W LF CREEK'NUCLEAR OPERATING CORPORATIONJohn P. BroschakVice President EngineeringMarch 20, 2013ET 13-0011U. S. Nuclear Regulatory CommissionATTN: Document Control DeskWashington, DC 20555

Reference:

1) Letter ET 12-0022, dated October 18, 2012, from J. P. Broschak,WCNOC, to USNRC2) Letter dated February 19, 2013, from C. F. Lyon, USNRC, to M. W.Sunseri, WCNOC, "Wolf Creek Generating Station -Request forAdditional Information Re: Request for Deviation from FireProtection Program Requirements for Volume Control Tank OutletValves (TAC NO. ME9823)"

Subject:

Docket No. 50-482: Response to Request for Additional InformationRegarding License Amendment Request for Deviation from FireProtection Program Requirements for Volume Control Tank Outlet ValvesGentlemen:Reference 1 provided Wolf Creek Nuclear Operating Corporation's (WCNOC) request for alicense amendment to revise Paragraph 2.C.(5)(a) of the renewed facility operating license andthe fire protection program as described in the Updated Safety Analysis Report (USAR) to allowa deviation from the separation requirements of 10 CFR Part 50, Appendix R, Section III.G.2,as documented in Appendix 9.5E of the Wolf Creek Generating Station USAR, for the volumecontrol tank outlet valves (BGLCV01 12B and BGLCV01 12C). Reference 2 provided a NuclearRegulatory Commission (NRC) request for additional information related to the application.Attachment I provides WCNOC's response to the request for additional information.The additional information does not expand the scope of the application, and does not impactthe no significant hazards consideration determination presented in Reference 1.In accordance with 10 CFR 50.91, "Notice for public comment; State consultation," a copy ofthis submittal is being provided to the designated Kansas State official.P.O. Box 411 / Burlington, KS 66839 / Phone: (620) 364-8831 AAn Equal Opportunity Employer M/F/HCNET LI([--,

ET 13-0011Page 2 of 3This letter contains no commitments. If you have any questions concerning this matter, pleasecontact me at (620) 364-4085, or Mr. Michael J. Westman at (620) 364-8831 ext. 4009.Sincerely,ý, &&-MýJohn P. BroschakJPB/rltAttachment I -Response to Request for Additional Informationcc: E. E. Collins (NRC), w/aT. A. Conley (NRC), w/aC. F. Lyon (NRC), w/aN. F. O'Keefe (NRC), w/aSenior Resident Inspector (NRC), w/a ET 13-0011Page 3 of 3STATE OF KANSASCOUNTY OF COFFEY)SJohn P. Broschak, of lawful age, being first duly sworn upon oath says that he is Vice PresidentEngineering of Wolf Creek Nuclear Operating Corporation; that he has read the foregoingdocument and knows the contents thereof; that he has executed the same for and on behalf ofsaid Corporation with full power and authority to do so; and that the facts therein stated are trueand correct to the best of his knowledge, information and belief.Jod. Broschak)_c President EngineeringSUBSCRIBED and sworn to before me this olG iday of(7areb,2013.I ~ ~ RHONA L. 1EEEOFFICIAL' YCMISO E.,,ý.SEAL:.Notary PublicExpiration Datei(9 LrL~2,V_C,/

Attachment I to ET 13-0011Page 1 of 4Response to Request for Additional InformationReference 1 provided Wolf Creek Nuclear Operating Corporation's (WCNOC) request for alicense amendment to revise Paragraph 2.C.(5)(a) of the renewed facility operating license andthe fire protection program as described in the Updated Safety Analysis Report (USAR) to allowa deviation from the separation requirements of 10 CFR Part 50, Appendix R, Section III.G.2,as documented in Appendix 9.5E of the Wolf Creek Generating Station USAR, for the volumecontrol tank outlet valves (BGLCV01 12B and BGLCV01 12C). Reference 2 provided a NuclearRegulatory Commission (NRC) request for additional information related to the application. Thespecific NRC questions are provided in italics.1. The LAR does not provide a description of the impact on the plant for a fire in room 1318.a. Please describe the impact on the plant and postulated scenario that requires anLAR for a fire in room 1318.Response: The postulated scenario that requires a license amendment request for a fire inroom 1318 is a design basis fire in fire area A-8 that damages both redundant volume controltank (VCT) isolation valves and prevents them from closing automatically or manually (from thecontrol room). The same fire is also postulated to affect makeup to the VCT. With anEmergency Core Cooling System (ECCS) centrifugal charging pump running and injecting intothe Reactor Coolant System (RCS), this scenario causes the VCT to drain and allow hydrogento enter the pump suction, causing damage to the pump.As discussed on page 12 of 15 of Reference 1, a fire contained within room 1318 will not causea loss of normal letdown. Consequently, makeup to the VCT will remain available, preventinghydrogen binding of the centrifugal charging pumps. A spurious low-low VCT level signal dueto damage to BGLT01 12 will initiate swapover to the Refueling Water Storage Tank (RWST)and open valve BNLCV01 12D (RWST to charging header valve). If this occurs with both VCToutlet valves open a net positive suction head will be maintained on the centrifugal chargingpumps because makeup to the VCT remains available and check valves in the RWST tocharging header prevent the VCT from draining to the RWST.In the event of a postulated fire in room 1318 that prevents closing one of the VCT outletvalves, post fire safe shutdown (PFSSD) is assured because makeup to the VCT remainsavailable. Therefore, the VCT is not expected to drain and hydrogen is not expected to enterthe ECCS centrifugal charging pump suction.Based on the above discussion, a postulated fire in room 1318 will have no adverse impact onthe PFSSD capability.

Attachment I to ET 13-0011Page 2 of 41. The LAR does not provide a description of the impact on the plant for a fire in room 1318.b. Please describe whether a loss of offsite power is credible for a fire in room 1318and, if credible, summarize the impact on the plant.Response: Loss of offsite power is not credible for a fire in room 1318. Calculation XX-E-013,"Post-Fire Safe Shutdown (PFSSD) Analysis," Appendix 2, provides a loss of offsite powerevaluation for fires outside the control room. The evaluation shows that a fire in fire area A-8could cause a loss of Train 'A' offsite and onsite power but will not cause a loss of Train 'B'onsite or offsite power. Further review of cable routing data shows that none of the Train 'A'onsite and offsite power cables run in room 1318. Therefore, a fire in room 1318 will not causea loss of either Train 'A' or Train 'B' offsite or onsite power.1. The LAR does not provide a description of the impact on the plant for a fire in room 1318.c. In the event a fire affects both volume control tank (VCT) outlet valves (bypreventing both valves from closing), please describe the operating proceduresavailable to the control room operators to close the VCT outlet valves.Response: Upon indication of a fire, control room operators enter procedure OFN KC-016,"Fire Response." Attachment B2 of OFN KC-016 provides a list of possible fire-induced failuresand mitigating operator actions in the event of a fire in fire area A-8. In the event the VCToutlet valves fail to close and makeup to the VCT is lost, operators are directed to stop theoperating ECCS centrifugal charging pump, line up centrifugal charging pump suction from theRWST, stop the reactor makeup water pumps and isolate the hydrogen supply to the VCT.These actions prevent hydrogen gas binding of the operating centrifugal charging pump incases where the VCT cannot be isolated. These actions are considered compensatorymeasures until approval of this license amendment request. Upon approval, the mitigatingaction will be revised to direct operators to line up RWST suction to the charging header andclose BGLCV0112B or BGLCV0112C from the control room.1. The LAR does not provide a description of the impact on the plant for a fire in room 1318.d. Please describe if there is a manual action to close the VCT outlet valves in theevent of a fire and, if so, provide a summary of the feasibility and reliability of themanual action.Response: There are no operator manual actions (local actions, in response to a fire) to closethe VCT outlet valves in the event of a fire in fire area A-8, as the outlet valves are located inthe fire area of concern. Operators would have to traverse the fire-affected area to close thevalve, which would not prove to be feasible or reliable. The license amendment request seeksapproval of the current configuration to credit the ability to close one of the two VCT outletvalves from the control room.As stated in the response to Question 1.c. above, upon approval of this license amendmentrequest, a control room operator action will have the operators close both VCT outlet valvesusing the hand switches in the control room. This action will be identified in procedure OFNKC-016, "Fire Response."

Attachment I to ET 13-0011Page 3 of 42. In Amendment No. 193, dated March 9, 2011 (ADAMS Accession No. MLl 10530183), adeviation was granted to the WCGS FPP for fire area A-8.a. Please identify all other deviations granted for area A-8.Response: There are two equipment hatches in fire area A-8 for which deviations weregranted. NUREG-0881, Supplement No. 5 (Reference 3), Section 9.5.1.4, "Fire Protection forSpecific Areas," states, in part:"The auxiliary building is provided with two sets of equipment hatchways in the northernand southern ends of the auxiliary building corridors. A monorail hoist serves each set ofhatchways to allow equipment to be moved from one location to another. Steel hatchcovers and automatic sprinkler water curtains are provided for each hatchway atelevations 2000 ft, 2026 ft, and 2047 ft to separate the corridor fire areas.Because of the low fuel loading and configuration of equipment in these areas, the stafffinds that the water curtains and steel covers provide a level of safety equivalent to thetechnical requirements of Section C.5.b of BTP CMEB 9.5-1."2. In Amendment No. 193, dated March 9, 2011 (ADAMS Accession No. MLl10530183), adeviation was granted to the WCGS FPP for fire area A-8.b. Please provide a technical justification that demonstrates that the current applicationwill not affect the conclusion of any prior deviation for area A-8.Response: License Amendment No. 193 (Reference 4) addresses the interface designation ofthe pressurizer power-operated relief valves (PORVs) from high/low pressure interface to non-high/low pressure interface. Cables associated with the Train 'A' pressurizer PORV andassociated block valve are run in fire area A-8. Therefore, fire area A-8 is included in the areasaffected by Amendment No. 193. The NRC staff conclusions in Section 3.3 of Reference 4state, in part:"The removal of the PORVs and block valves as high/low pressure interface componentsis a reduction in the PFSSD analysis methodology contained in WCNOC's PFSSDanalysis. However, the defense-in-depth measures provide reasonable assurance that afire that does occur will be limited in severity and that there is reasonable assurance thatsafe shutdown can be achieved."The defense-in-depth measures provided in fire area A-8 are not affected by the current licenseamendment request (Reference 1). Therefore, Amendment No. 193 is not affected byReference 1.The license amendment request (Reference 1) does not affect the conclusion in Section 9.5.1.4of Reference 3 regarding equipment hatch covers. The low combustible loading configurationof the equipment hatch covers and automatic suppression and detection provides anacceptable defense-in-depth approach commensurate with the area hazards. The nearestequipment hatch is located approximately 30 feet horizontally from the room 1318 door.

Attachment I to ET 13-0011Page 4 of 4

References:

1. Letter ET 12-0022, "License Amendment Request (LAR) for Deviation from FireProtection Program Requirements -Volume Control Tank Outlet Valves," October 18,2012. ADAMS Accession No. ML12299A312.2. Letter from C. F. Lyon, USNRC, to M. W. Sunseri, WCNOC, "Wolf Creek GeneratingStation -Request for Additional Information Re: Request for Deviation from FireProtection Program Requirements for Volume Control Tank Outlet Valves (TAC NO.ME9823)," February 19, 2013. ADAMS Accession No. ML13046A100.3. NURE-0881, "Safety Evaluation Report related to the operation of Wolf Creek GeneratingStation, Unit No. 1," Supplement No. 5, March 1985.4. Letter from B. K. Singal, USNRC, to M. W. Sunseri, WCNOC, "Wolf Creek GeneratingStation -Issuance of Amendment re: Removing High/Low Pressure Designation from thePressurizer Power-Operated Relief Valves (TAC NO. ME3766)," March 9, 2011. ADAMSAccession No. ML110530183.