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{{Adams
#REDIRECT [[05000370/LER-2015-001]]
| number = ML15343A011
| issue date = 12/07/2015
| title = LER 15-001-00 for McGuire, Unit 2, Regarding Auxiliary Feedwater System Actuation While in Mode 4
| author name = Capps S D
| author affiliation = Duke Energy Carolinas, LLC
| addressee name =
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000370
| license number =
| contact person =
| case reference number = MNS-15-092
| document report number = LER 15-001-00
| document type = Letter, Licensee Event Report (LER)
| page count = 7
}}
 
=Text=
{{#Wiki_filter:~ENERGY%Steven D. CappsVice PresidentMoGuire Nuclear StationDuke EnergyMG01VP I112700 Hagers Ferry RoadHuntersville, NC 27078o: 980.875.4805f: 980.875.4809Steven .Capps@duke-energy.comSerial No: MNS-15-092December 07, 2015U.S. Nuclear Regulatory Commission 10 CFR 50.73ATTENTION: Document Control DeskWashington, D.C. 20555
 
==Subject:==
Duke Energy Carolinas, LLCMcGuire Nuclear Station (MNS), Unit 2Docket No. 50-370Licensee Event Report 370/2015-01, Revision 0Nuclear Condition Report: 1961955Pursuant to 10 CFR 50.73 Section (a) (1) and (d), attached is Licensee Event Report(LER) 370/2015-01, Revision 0, regarding an actuation of the Unit 2 Auxiliary FeedwaterSystem while in Mode 4.This report is being submitted in accordance with 10 CFR 50.73(a) (2) (iv) (A), SystemActuation.This event is considered to be of no significance with respect to the health and safety ofthe public.There are no regulatory commitments contained in this LER.If questions arise regarding this LER, please contact George Murphy of RegulatoryAffairs at 980-875-5715.Sincerely,Steven D. CappsAttachment U.S. Nuclear Regulatory CommissionDecember 07, 2015Page 2cc: C. HaneyAdministrator, Region IIU.S. Nuclear Regulatory CommissionMarquis One Tower245 Peachtree Center Ave.NE Suite 1200, 30303-1257Atlanta, Ga 30303-1 257G. E. MillerProject Manager (McGuire)U.S. Nuclear Regulatory Commission11555 Rockville PikeRockville, MD 20852-2738Mail Stop 0-8 G9AJ. ZeilerNRC Senior Resident InspectorMcGuire Nuclear StationW. L. Cox, Ill, Section ChiefNorth Carolina Department of Health and Human ServicesRadiation Protection Section1645 Mail Service CenterRaleigh, NC 27699-1645 NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB:-NO.3150-0104 'EXPIRES: 01/31/2017 -(02-2014) Estimated burden per response to comply with this mandatory collection request: 80 hours.lessons lesrned are incorporated into the licensing process end fed bsck to industry.comments regarding burden estimate to the FOIA, Privacy end Information CollectionsBranch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by(LER)internet e-mail to infocollects Resource@nrc.gov, and to the Desk Officer, Office of informationK9LICENSEE EVENT REPORT(ERand Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget,(See page 2 for required number of Washington, DC 20503. If a means used to impose an information collection does not display adigits/characters for each blc)currently valid 0MB control number, the NRC may not conduct or sponsor, and a person is notblock)required to respond to, the information collection.1. FACILITY NAME 2. DOCKET NUMBER 3. PAGEMcGuire Nuclear Station, Unit 2 05000370 1 OF 54. TITLEAuxiliary Feedwater System Actuation While in Mode 4 _ _________________5. EVENT DATE 6. LER NUMBER 7. REPORT DATE J8. OTHER FACILITIES INVOLVEDSEUNIL RVFACILITY NAME DOCKET NUMBERMO DAY YEAR YEAR NUMBER NO MO DAY YEAR jNoneIFACILITY NAME DOCKET NUMBER10 07 2015 2015-01 0 12 07 2015 jNone11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)9. OPERATING MODEEl 20.2201(b) El 20.2203(a)(3)(i) El 50.73(a)(2)(i)(C) El 50.73(a)(2)(vii)Mode 4 El 20.2201(d) El 20.2203(a)(3)(ii) El 50.73(a)(2)(ii)(A) El 50.73(a)(2)(viii)(A)El 20.2203(a)(1) El 20.2203(a)(4) El 50.73(a)(2)(ii)(g) El 50.73(a)(2)(viii)(g)____________E 20.2203(a)(2)(i) El 50.36(c)(1)(i)(A) El 50.73(a)(2)(iii) El 50.73(a)(2)(ix)(A)El 20.2203(a)(2)(ii) El 50.36(c)(1)(ii)(A) [] 50.73(a)(2)(iv)(A) El 50.73(a)(2)(x)10. POWER LEVEL El 20.2203(a)(2)(iii) El 50.36(c)(2) El 50.73(a)(2)(v)(A) El 73.71(a)(4)El 20.2203(a)(2)(iv) El 50.46(a)(3)(ii) El 50.73(a)(2)(v)(B) El 73.71(a)(5)El 20.2203(a)(2)(v) El 50.73(a)(2)(i)(A) El 50.73(a)(2)(v)(C) El OTHER000 El 20.2203(a)(2)(vi) El 50.73(a)(2)(i)(B) El 50.73(a)(2)(v)(D) El Specify in Abstract belowor in NRC Form 366A12. LICENSEE CONTACT FOR THIS LERFACILITY NAME TELEPHONE NUMBER (Include Area Code)George Murphy, Regulatory Affairs 980-875-571513. COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORTMANU- REPORTABLE ''MANU- "REPORTABLECAUSE SYSTEM COMPONENT FACTURER TO EPIX CAUSE SYSTEM COMPONENT r-,T IRFR TO EPIX14. SUPPLEMENTAL REPORT EXPECTED ] XP.E MONTH DAY YEARYES (If yes, complete EXPECTED SUBMISSION DATE) X INO SUBMISSION_______16. ABSTRACT (Limit to 1400 Spaces, i.e., approximately 15 single-spaced typewritten lines)On October 7, 2015, an actuation of the Auxiliary Feedwater (CA) system occurred while Unit 2 was in Mode 4and operators were restoring from testing of the 2A Solid State Protection System (SSPS) Safety Injection (SI)trip functions for the Main Turbine and the Main Feedwater (CE) pump turbines. The CA actuation caused the2A CA Train flow control valves to fully open and the associated steam generator (SG) sampling and blowdownvalves to close. The actuation occurred as designed, and there was no adverse impact to plant operation.At the time the CA actuation, the cF pumps were shut down and SG levels were being maintained by the 2Aand 2B Motor Driven CA Pumps (MDCAP)s. During restoration from SSPS testing, a conditional step in theprocedure did not clearly require the reset of at least one CF pump. Leaving both CF pumps in the trippedstate provided the logic for the CA actuation signal. The actuation occurred when the 2A Train CA auto startdefeat switch was placed in "reset" as directed by the test procedure. To prevent the CA actuation, the testprocedure should have ensured that at least one CF pump was in "reset" before the 2A CA Train auto startdefeat switch was placed in "reset".Procedures PT/1lA/4200/026A and PTI2/1A42001026A will be revised to clearly define the CF pump as foundand restoration configuration based on actual plant conditions.
NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB: NO. 3150-0104 EXPIRES: 01/31/2017(02-:2014) .. ....... Estimated burden per: response to cbmply this- mandatory collection request: B0tibirs.Reported lessons learned are incorporated into the licensing process and fed back to industry.comments regarding burden estimate to the FOIA, Privacy and Information Collections,rl ~ u,,Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or byS" LICENSEE EVENT REPORT (LER) internet e-mail to infocollects Resource@nrc.gov, and to the Desk Officer, Office of InformationSCONTINUATION SHEET and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget,Washington, DC 20503. If a means used to impose an information collection does not display avalid 0MB control number, the NRC may not conduct or sponsor, and a person is notrequired to respond to, the information collection.1. FACILITY NAME j2. DOCKET 6. LER NUMBER 3. PAGEISEQUENTIAL IREVISIONI .YEAR NUMBER -NUMBERMcGuire Nuclear Station, Unit 2 j05000370 2015 _ 01 -00 2 OF 517. NARRATIVEBACKGROUND:This event is being reported under the following criterion:10 CFR 50.73(a)(2)(iv)(A), for any event or condition that resulted in automatic actuation of the PWRauxiliary feedwater system.The Auxiliary Feedwater (CA) System [EIIS: BA] automatically supplies feedwater to the SGs to removedecay heat from the Reactor Coolant (NC) System [EllS: AB] upon the loss of Main Feedwater (CF)System supply [EllS:S J]. The CA pumps [EIIS: P] take suction from the CA System Storage Tank (CAST)[EllS: KA] and pump to the Steam Generator (SG) secondary side.The CA System consists of two motor driven CA pumps (MDCAP)s and one steam turbine driven pump(TDCAP), configured into three trains. Each of the MDCAPs supplies 100% of the flow requirements to twoof the four SGs, and each MDCAP has the capability to be realigned to feed the other SGs. The TDCAPprovides 200% of the flow requirements and supplies water to all four SGs. Each MDCAP is powered froman independent Class I E power supply. The TDCAP receives steam from two Main Steam (SM) System[EllS: SB] lines upstream of the Main Steam isolation valves [EIIS:SA]. Each of the steam feed lines willsupply 100% of the requirements of the TDCAP. The SGs function as a heat sink for core decay heat, andthe CA System is designed to supply sufficient water to the SGs to remove decay heat. The CA System iscapable of supplying feedwater to the SGs during normal unit startup, shutdown, and hot standbyconditions. The MDCAPs actuate automatically on SG water level Lo-Lo in one out of four SGs by theEngineered Safety Features Actuation System (ESFAS) [EIIS:JE]. The MDCAPs also actuate on loss ofoffsite power, safety injection, ATWS (Anticipated Transients Without Scram) Mitigation System ActuationCircuitry (AMSAC) and trip of all CF pumps. The TDCAP actuates automatically on SG water level Lo-Lo intwo out of four SGs and on loss of offsite power.Technical Specification 3.7.5 governs the CA System. Limiting Condition of Operation 3.7.5 requires threeCA trains to be operable in Modes 1, 2, and 3. In Mode 4 when the SGs are relied upon for heat removal,one motor driven CA train is required to be operable.
NRC FORM _366A u.S. NUCLEAR. REGULATORY COMMISSION APPROVED BY 0MB: NO. 3 150:0104 EXPIRES: 01/31/20.17(02-2014) -Estimated burden per response lb compljywith this mandatory~eollection requrit: 80 hours.Reported lessons learned are incorporated int the licensing process end fed bsck to industry.comments regsrding burden estimate to the FOIA, Privacy end Information Collectionsd~ 't~.Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington. DC020555-0001, or by/ ,LICENSEE EVENT REPORT (LER) internet s-mail to infocollects Resource@nrc.gov, and to the Desk Officer. Office of Information, CO TN A IN S E Tand Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget,"; C NTIUATI N S EETWashington, DC 20503. If a means used to impose an information collection doss not display a=°*".currently valid 0MB control number, the NRC may not conduct or sponsor, and a person is notrequired to respond to, the information collection.1. FACILITY NAME 2. DOCKET 6. LER NUMBER 3. PAGESEQUENTIAL REVISIONYEAR NUMBER NUMBERMcGuire Nuclear Station, Unit 2 05000370 2015 -01 _ 00 3 OF 517. NARRATIVEEVENT DESCRIPTION:On October 7, 2015, an actuation of the CA system occurred while Unit 2 was in Mode 4 and operatorswere restoring from testing the 2A Train Solid State Protection System (SSPS) Safety Injection (SI) tripfunctions for the Main Turbine and the CF pump turbines. The testing was performed under the guidanceof procedure PTI21AI42001026A, "Turbine and Main Feedwater Pump Turbine (MFWPT) Trips from SSPS".The CA actuation caused the 2A CA train flow control valves to fully open. The signal also caused theassociated SG sampling and blowdown valves to close. The actuation occurred as designed and there wasno adverse impact to plant operation.The operating crew responded to the 2A CA Auto Start signal and managed SG levels by taking manualcontrol of the 2A CA flow control valves. Affected components were aligned for the plant conditions usingnormal operating procedures. Nuclear Safety was not impacted by this event.During and after SSPS testing, the CF pumps were shut down and SG levels were being maintained by the2A and 2B MDCAPs. During restoration from SSPS testing, a conditional step in the procedure did notclearly require the reset of at least one CF pump. Leaving both CF pumps in the tripped state provided thelogic for the CA actuation signal (trip of all CF pumps). However, the actuation signal was blocked until the2A CA auto start defeat switch was placed in "reset" during restoration bY the test procedure. The testprocedure should have ensured that at least one CF pump was reset from the tripped state before the 2ACA Train auto start defeat switch was placed in "reset".The CA actuation occurred during the performance of PT/2/A/4200/026A, "Turbine and MFWPT Trips fromSSPS", system restoration section. When the CA Auto Start Defeat switch was placed in "reset", with bothCF Pumps in the tripped condition, the trip of all CF pumps signal was enabled. The trip of all CF pumpsprovides protection for a loss of main feedwater. SG levels were being maintained by the MDCAPs, andtherefore, plant conditions did not require the CA actuation.Use of PTI21AI42001026A and the testing that resulted in the CA actuation have been successfullyperformed in the past; however, performance of the test usually occurs before completion ofOP/21AI6250/O02, "Auxiliary Feedwater System"- enclosure 4.1, "Alignment for Standby Readiness'- with CFin operation. The re-sequencing of these activities exposed the deficiency in PT/2/A/4200/026A, whichresulted in the CA actuation.Sequence of EventsDate/Time Activity10/6/15 / 1350 Unit 2 entered Mode 410/7/15 / 0027 -CA Aligned for Standby Readiness (OP/2/AI6250/O02)10/7/15 / 0600 -Turbine and MFWPT Trips from SSPS started (PT/2/N42001026A)10/7/15 / 0630 Turnover occurred to Dayshift (realignment from test not complete)10/7/15 / 0655 -Unblocked 2A CA Auto Start Defeat per PT/21A/4200/026 A (2A CA Actuation)
NRC FORM 366A u.s. NUCLEAR REGULATORY COMMISSION` APPROVED BY 0MB: NO. 3 150-0104 EXPIRES: 01/31/2017(02-2014) --Estimated burden per" r~esponse to cornply with this mandatory ct11ection request: 80Pioiurs.Reported lessons learned are incorporated into the licensing process and fed back to industry.comments regarding burden estimate to the FOtA, Privacy and Information Collections' (T-5 F53), U.S. Nuclear Regulatory Commission, Washington. DC 20555-0001, or by__ LICENSEE EVENT REPORT (LER) internet e-mail to infocollects Resource@nrc.gov, and to the Desk Officer, Office of InformationjCONTINUATION SHEET and Regulatory Affairs, NEOB-10202,.(3150-0104), Office of Management and Budget,Washington, DC 20503. Ifsa means used to impose an information collection does not display avalid 0MB control number, the NRC may not conduct or sponsor, and a person is notrequired to respond to, the information collection.1. FACILITY NAME 2. DOCKET 6. LER NUMBER 3. PAGESEQUENTIAL REVISIONYEAR NUMBER NUMBERMcGuire Nuclear Station, Unit 2 05000370 2015 _ 00 4 OF 517. NARRATIVECAUSAL FACTORS:The cause of this event was a procedure weakness that did not clearly define the CF pump restorationconditions after testing was complete.Basis:PT/2/A/4200/026A has been performed successfully in the past. In this instance, the CA system was aligned forStandby Readiness before the PT was performed. This set up conditions that had not been present duringprevious performances of the PT, which led to the CA actuation. As a result of the SSPS test, both CF pumpswere still tripped. The test procedure did not realign at least one CF pump to the as-found ("reset") conditionduring restoration after testing was complete. In this event, because the CA system was aligned for StandbyReadiness when the test was performed, the test procedure should have ensured the as-found condition was"reset" on at least one of the CF pumps. The procedure did not account for the CA system to be aligned forStandby Readiness even though the procedure tripped the CF pumps in a previous step. Without placing at leastone CF pump in "reset" before resetting the CA auto start defeat switch to "reset" allowed the CA actuation tooccur. Adequate guidance was missing for proper performance of step 12.4.20 in the test procedure.CORRECTIVE ACTIONS:Immediate:1. Operators took manual control of CA control valves and restored plant conditions.2. The affected test procedures were placed on Administrative Hold to prevent use until revised.Planned:1. PTI1A1A4200/O26A and PTI21AI42001026A, "~Turbine and MFWPT Trips from SSPS" will be revised-toensure this event does not reoccur.
NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION -APPROVED BlY 0MB: NO. 3 150-0104 EXPIRES: 01/31/2017(02-201 4) .. ..". .."-. .Estimated burden per response to Comply withthilsmandatory collection req~uest: 80 h'ouirs. -Reported lessons learned are incorporated into the licensing process and fed back to industry.comments regarding burden estimate to the FOIA, Privacy end Information Collections'., COTIUTINEVNT REPORTSHE(LER) Branch Reuaoyad(T-5 e-mal)t U.S. Nuclear Regulatory (35-14,Commission, OftoadWashington, MngmtfOicrDekheDC 20555-0001, BdeadOfieor by-,- Washington, DC 20503. If a means used to impose an information collection does not display acurrently valid 0MB control number, the NRC may not conduct or sponsor, and a person is notrequired to respond to. the information collection.1. FACILITY NAME 2. DOCKET 6. LER NUMBER 3. PAGEISEQUENTIAL I REVISIONYEAR j NUMBER INUMBERMcGuire Nuclear Station, Unit 2 05000370 2015 00 5 OF 517. NARRATIVESAFETY ANALYSIS:At the time of the CA system actuation, the CF system was shut down and the CA system was supplyingfeedwater to the SGs. No actual loss of feedwater occurred. The plant was returning from a refuelingoutage with low decay heat level due to the extended shutdown and new fuel in the reactor. Decay heatremoval using the SGs was not challenged. The signal (trip of all CF pumps) that caused the CA actuationwas not required to be operable in Mode 4. The signal is required by TS 3.3.2 to be operable in Modes 1-3only.In conclusion, this event is Considered to be of low safety significance. The CA system responded asdesigned. This event was of no significance to the health and safety of the public.ADDITIONAL IN FORMATION:A three year search of the McGuire corrective action database revealed no other CA actuation eventsresulting from a latent procedural deficiency. Therefore, this event is not recurring.This event is not considered to constitute a Safety System Functional Failure. This event only involved theactuation of the CA System. It was determined through the extent of condition review that the conditiondescribed in this LER affects both CA Trains on both units. The planned action will address the extent ofcondition. There was no release of radioactive material, radiation overexposure, or personnel injuryassociated with the event described in this LER.
~ENERGY%Steven D. CappsVice PresidentMoGuire Nuclear StationDuke EnergyMG01VP I112700 Hagers Ferry RoadHuntersville, NC 27078o: 980.875.4805f: 980.875.4809Steven .Capps@duke-energy.comSerial No: MNS-15-092December 07, 2015U.S. Nuclear Regulatory Commission 10 CFR 50.73ATTENTION: Document Control DeskWashington, D.C. 20555
 
==Subject:==
Duke Energy Carolinas, LLCMcGuire Nuclear Station (MNS), Unit 2Docket No. 50-370Licensee Event Report 370/2015-01, Revision 0Nuclear Condition Report: 1961955Pursuant to 10 CFR 50.73 Section (a) (1) and (d), attached is Licensee Event Report(LER) 370/2015-01, Revision 0, regarding an actuation of the Unit 2 Auxiliary FeedwaterSystem while in Mode 4.This report is being submitted in accordance with 10 CFR 50.73(a) (2) (iv) (A), SystemActuation.This event is considered to be of no significance with respect to the health and safety ofthe public.There are no regulatory commitments contained in this LER.If questions arise regarding this LER, please contact George Murphy of RegulatoryAffairs at 980-875-5715.Sincerely,Steven D. CappsAttachment U.S. Nuclear Regulatory CommissionDecember 07, 2015Page 2cc: C. HaneyAdministrator, Region IIU.S. Nuclear Regulatory CommissionMarquis One Tower245 Peachtree Center Ave.NE Suite 1200, 30303-1257Atlanta, Ga 30303-1 257G. E. MillerProject Manager (McGuire)U.S. Nuclear Regulatory Commission11555 Rockville PikeRockville, MD 20852-2738Mail Stop 0-8 G9AJ. ZeilerNRC Senior Resident InspectorMcGuire Nuclear StationW. L. Cox, Ill, Section ChiefNorth Carolina Department of Health and Human ServicesRadiation Protection Section1645 Mail Service CenterRaleigh, NC 27699-1645 NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB:-NO.3150-0104 'EXPIRES: 01/31/2017 -(02-2014) Estimated burden per response to comply with this mandatory collection request: 80 hours.lessons lesrned are incorporated into the licensing process end fed bsck to industry.comments regarding burden estimate to the FOIA, Privacy end Information CollectionsBranch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by(LER)internet e-mail to infocollects Resource@nrc.gov, and to the Desk Officer, Office of informationK9LICENSEE EVENT REPORT(ERand Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget,(See page 2 for required number of Washington, DC 20503. If a means used to impose an information collection does not display adigits/characters for each blc)currently valid 0MB control number, the NRC may not conduct or sponsor, and a person is notblock)required to respond to, the information collection.1. FACILITY NAME 2. DOCKET NUMBER 3. PAGEMcGuire Nuclear Station, Unit 2 05000370 1 OF 54. TITLEAuxiliary Feedwater System Actuation While in Mode 4 _ _________________5. EVENT DATE 6. LER NUMBER 7. REPORT DATE J8. OTHER FACILITIES INVOLVEDSEUNIL RVFACILITY NAME DOCKET NUMBERMO DAY YEAR YEAR NUMBER NO MO DAY YEAR jNoneIFACILITY NAME DOCKET NUMBER10 07 2015 2015-01 0 12 07 2015 jNone11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)9. OPERATING MODEEl 20.2201(b) El 20.2203(a)(3)(i) El 50.73(a)(2)(i)(C) El 50.73(a)(2)(vii)Mode 4 El 20.2201(d) El 20.2203(a)(3)(ii) El 50.73(a)(2)(ii)(A) El 50.73(a)(2)(viii)(A)El 20.2203(a)(1) El 20.2203(a)(4) El 50.73(a)(2)(ii)(g) El 50.73(a)(2)(viii)(g)____________E 20.2203(a)(2)(i) El 50.36(c)(1)(i)(A) El 50.73(a)(2)(iii) El 50.73(a)(2)(ix)(A)El 20.2203(a)(2)(ii) El 50.36(c)(1)(ii)(A) [] 50.73(a)(2)(iv)(A) El 50.73(a)(2)(x)10. POWER LEVEL El 20.2203(a)(2)(iii) El 50.36(c)(2) El 50.73(a)(2)(v)(A) El 73.71(a)(4)El 20.2203(a)(2)(iv) El 50.46(a)(3)(ii) El 50.73(a)(2)(v)(B) El 73.71(a)(5)El 20.2203(a)(2)(v) El 50.73(a)(2)(i)(A) El 50.73(a)(2)(v)(C) El OTHER000 El 20.2203(a)(2)(vi) El 50.73(a)(2)(i)(B) El 50.73(a)(2)(v)(D) El Specify in Abstract belowor in NRC Form 366A12. LICENSEE CONTACT FOR THIS LERFACILITY NAME TELEPHONE NUMBER (Include Area Code)George Murphy, Regulatory Affairs 980-875-571513. COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORTMANU- REPORTABLE ''MANU- "REPORTABLECAUSE SYSTEM COMPONENT FACTURER TO EPIX CAUSE SYSTEM COMPONENT r-,T IRFR TO EPIX14. SUPPLEMENTAL REPORT EXPECTED ] XP.E MONTH DAY YEARYES (If yes, complete EXPECTED SUBMISSION DATE) X INO SUBMISSION_______16. ABSTRACT (Limit to 1400 Spaces, i.e., approximately 15 single-spaced typewritten lines)On October 7, 2015, an actuation of the Auxiliary Feedwater (CA) system occurred while Unit 2 was in Mode 4and operators were restoring from testing of the 2A Solid State Protection System (SSPS) Safety Injection (SI)trip functions for the Main Turbine and the Main Feedwater (CE) pump turbines. The CA actuation caused the2A CA Train flow control valves to fully open and the associated steam generator (SG) sampling and blowdownvalves to close. The actuation occurred as designed, and there was no adverse impact to plant operation.At the time the CA actuation, the cF pumps were shut down and SG levels were being maintained by the 2Aand 2B Motor Driven CA Pumps (MDCAP)s. During restoration from SSPS testing, a conditional step in theprocedure did not clearly require the reset of at least one CF pump. Leaving both CF pumps in the trippedstate provided the logic for the CA actuation signal. The actuation occurred when the 2A Train CA auto startdefeat switch was placed in "reset" as directed by the test procedure. To prevent the CA actuation, the testprocedure should have ensured that at least one CF pump was in "reset" before the 2A CA Train auto startdefeat switch was placed in "reset".Procedures PT/1lA/4200/026A and PTI2/1A42001026A will be revised to clearly define the CF pump as foundand restoration configuration based on actual plant conditions.
NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB: NO. 3150-0104 EXPIRES: 01/31/2017(02-:2014) .. ....... Estimated burden per: response to cbmply this- mandatory collection request: B0tibirs.Reported lessons learned are incorporated into the licensing process and fed back to industry.comments regarding burden estimate to the FOIA, Privacy and Information Collections,rl ~ u,,Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or byS" LICENSEE EVENT REPORT (LER) internet e-mail to infocollects Resource@nrc.gov, and to the Desk Officer, Office of InformationSCONTINUATION SHEET and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget,Washington, DC 20503. If a means used to impose an information collection does not display avalid 0MB control number, the NRC may not conduct or sponsor, and a person is notrequired to respond to, the information collection.1. FACILITY NAME j2. DOCKET 6. LER NUMBER 3. PAGEISEQUENTIAL IREVISIONI .YEAR NUMBER -NUMBERMcGuire Nuclear Station, Unit 2 j05000370 2015 _ 01 -00 2 OF 517. NARRATIVEBACKGROUND:This event is being reported under the following criterion:10 CFR 50.73(a)(2)(iv)(A), for any event or condition that resulted in automatic actuation of the PWRauxiliary feedwater system.The Auxiliary Feedwater (CA) System [EIIS: BA] automatically supplies feedwater to the SGs to removedecay heat from the Reactor Coolant (NC) System [EllS: AB] upon the loss of Main Feedwater (CF)System supply [EllS:S J]. The CA pumps [EIIS: P] take suction from the CA System Storage Tank (CAST)[EllS: KA] and pump to the Steam Generator (SG) secondary side.The CA System consists of two motor driven CA pumps (MDCAP)s and one steam turbine driven pump(TDCAP), configured into three trains. Each of the MDCAPs supplies 100% of the flow requirements to twoof the four SGs, and each MDCAP has the capability to be realigned to feed the other SGs. The TDCAPprovides 200% of the flow requirements and supplies water to all four SGs. Each MDCAP is powered froman independent Class I E power supply. The TDCAP receives steam from two Main Steam (SM) System[EllS: SB] lines upstream of the Main Steam isolation valves [EIIS:SA]. Each of the steam feed lines willsupply 100% of the requirements of the TDCAP. The SGs function as a heat sink for core decay heat, andthe CA System is designed to supply sufficient water to the SGs to remove decay heat. The CA System iscapable of supplying feedwater to the SGs during normal unit startup, shutdown, and hot standbyconditions. The MDCAPs actuate automatically on SG water level Lo-Lo in one out of four SGs by theEngineered Safety Features Actuation System (ESFAS) [EIIS:JE]. The MDCAPs also actuate on loss ofoffsite power, safety injection, ATWS (Anticipated Transients Without Scram) Mitigation System ActuationCircuitry (AMSAC) and trip of all CF pumps. The TDCAP actuates automatically on SG water level Lo-Lo intwo out of four SGs and on loss of offsite power.Technical Specification 3.7.5 governs the CA System. Limiting Condition of Operation 3.7.5 requires threeCA trains to be operable in Modes 1, 2, and 3. In Mode 4 when the SGs are relied upon for heat removal,one motor driven CA train is required to be operable.
NRC FORM _366A u.S. NUCLEAR. REGULATORY COMMISSION APPROVED BY 0MB: NO. 3 150:0104 EXPIRES: 01/31/20.17(02-2014) -Estimated burden per response lb compljywith this mandatory~eollection requrit: 80 hours.Reported lessons learned are incorporated int the licensing process end fed bsck to industry.comments regsrding burden estimate to the FOIA, Privacy end Information Collectionsd~ 't~.Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington. DC020555-0001, or by/ ,LICENSEE EVENT REPORT (LER) internet s-mail to infocollects Resource@nrc.gov, and to the Desk Officer. Office of Information, CO TN A IN S E Tand Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget,"; C NTIUATI N S EETWashington, DC 20503. If a means used to impose an information collection doss not display a=°*".currently valid 0MB control number, the NRC may not conduct or sponsor, and a person is notrequired to respond to, the information collection.1. FACILITY NAME 2. DOCKET 6. LER NUMBER 3. PAGESEQUENTIAL REVISIONYEAR NUMBER NUMBERMcGuire Nuclear Station, Unit 2 05000370 2015 -01 _ 00 3 OF 517. NARRATIVEEVENT DESCRIPTION:On October 7, 2015, an actuation of the CA system occurred while Unit 2 was in Mode 4 and operatorswere restoring from testing the 2A Train Solid State Protection System (SSPS) Safety Injection (SI) tripfunctions for the Main Turbine and the CF pump turbines. The testing was performed under the guidanceof procedure PTI21AI42001026A, "Turbine and Main Feedwater Pump Turbine (MFWPT) Trips from SSPS".The CA actuation caused the 2A CA train flow control valves to fully open. The signal also caused theassociated SG sampling and blowdown valves to close. The actuation occurred as designed and there wasno adverse impact to plant operation.The operating crew responded to the 2A CA Auto Start signal and managed SG levels by taking manualcontrol of the 2A CA flow control valves. Affected components were aligned for the plant conditions usingnormal operating procedures. Nuclear Safety was not impacted by this event.During and after SSPS testing, the CF pumps were shut down and SG levels were being maintained by the2A and 2B MDCAPs. During restoration from SSPS testing, a conditional step in the procedure did notclearly require the reset of at least one CF pump. Leaving both CF pumps in the tripped state provided thelogic for the CA actuation signal (trip of all CF pumps). However, the actuation signal was blocked until the2A CA auto start defeat switch was placed in "reset" during restoration bY the test procedure. The testprocedure should have ensured that at least one CF pump was reset from the tripped state before the 2ACA Train auto start defeat switch was placed in "reset".The CA actuation occurred during the performance of PT/2/A/4200/026A, "Turbine and MFWPT Trips fromSSPS", system restoration section. When the CA Auto Start Defeat switch was placed in "reset", with bothCF Pumps in the tripped condition, the trip of all CF pumps signal was enabled. The trip of all CF pumpsprovides protection for a loss of main feedwater. SG levels were being maintained by the MDCAPs, andtherefore, plant conditions did not require the CA actuation.Use of PTI21AI42001026A and the testing that resulted in the CA actuation have been successfullyperformed in the past; however, performance of the test usually occurs before completion ofOP/21AI6250/O02, "Auxiliary Feedwater System"- enclosure 4.1, "Alignment for Standby Readiness'- with CFin operation. The re-sequencing of these activities exposed the deficiency in PT/2/A/4200/026A, whichresulted in the CA actuation.Sequence of EventsDate/Time Activity10/6/15 / 1350 Unit 2 entered Mode 410/7/15 / 0027 -CA Aligned for Standby Readiness (OP/2/AI6250/O02)10/7/15 / 0600 -Turbine and MFWPT Trips from SSPS started (PT/2/N42001026A)10/7/15 / 0630 Turnover occurred to Dayshift (realignment from test not complete)10/7/15 / 0655 -Unblocked 2A CA Auto Start Defeat per PT/21A/4200/026 A (2A CA Actuation)
NRC FORM 366A u.s. NUCLEAR REGULATORY COMMISSION` APPROVED BY 0MB: NO. 3 150-0104 EXPIRES: 01/31/2017(02-2014) --Estimated burden per" r~esponse to cornply with this mandatory ct11ection request: 80Pioiurs.Reported lessons learned are incorporated into the licensing process and fed back to industry.comments regarding burden estimate to the FOtA, Privacy and Information Collections' (T-5 F53), U.S. Nuclear Regulatory Commission, Washington. DC 20555-0001, or by__ LICENSEE EVENT REPORT (LER) internet e-mail to infocollects Resource@nrc.gov, and to the Desk Officer, Office of InformationjCONTINUATION SHEET and Regulatory Affairs, NEOB-10202,.(3150-0104), Office of Management and Budget,Washington, DC 20503. Ifsa means used to impose an information collection does not display avalid 0MB control number, the NRC may not conduct or sponsor, and a person is notrequired to respond to, the information collection.1. FACILITY NAME 2. DOCKET 6. LER NUMBER 3. PAGESEQUENTIAL REVISIONYEAR NUMBER NUMBERMcGuire Nuclear Station, Unit 2 05000370 2015 _ 00 4 OF 517. NARRATIVECAUSAL FACTORS:The cause of this event was a procedure weakness that did not clearly define the CF pump restorationconditions after testing was complete.Basis:PT/2/A/4200/026A has been performed successfully in the past. In this instance, the CA system was aligned forStandby Readiness before the PT was performed. This set up conditions that had not been present duringprevious performances of the PT, which led to the CA actuation. As a result of the SSPS test, both CF pumpswere still tripped. The test procedure did not realign at least one CF pump to the as-found ("reset") conditionduring restoration after testing was complete. In this event, because the CA system was aligned for StandbyReadiness when the test was performed, the test procedure should have ensured the as-found condition was"reset" on at least one of the CF pumps. The procedure did not account for the CA system to be aligned forStandby Readiness even though the procedure tripped the CF pumps in a previous step. Without placing at leastone CF pump in "reset" before resetting the CA auto start defeat switch to "reset" allowed the CA actuation tooccur. Adequate guidance was missing for proper performance of step 12.4.20 in the test procedure.CORRECTIVE ACTIONS:Immediate:1. Operators took manual control of CA control valves and restored plant conditions.2. The affected test procedures were placed on Administrative Hold to prevent use until revised.Planned:1. PTI1A1A4200/O26A and PTI21AI42001026A, "~Turbine and MFWPT Trips from SSPS" will be revised-toensure this event does not reoccur.
NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION -APPROVED BlY 0MB: NO. 3 150-0104 EXPIRES: 01/31/2017(02-201 4) .. ..". .."-. .Estimated burden per response to Comply withthilsmandatory collection req~uest: 80 h'ouirs. -Reported lessons learned are incorporated into the licensing process and fed back to industry.comments regarding burden estimate to the FOIA, Privacy end Information Collections'., COTIUTINEVNT REPORTSHE(LER) Branch Reuaoyad(T-5 e-mal)t U.S. Nuclear Regulatory (35-14,Commission, OftoadWashington, MngmtfOicrDekheDC 20555-0001, BdeadOfieor by-,- Washington, DC 20503. If a means used to impose an information collection does not display acurrently valid 0MB control number, the NRC may not conduct or sponsor, and a person is notrequired to respond to. the information collection.1. FACILITY NAME 2. DOCKET 6. LER NUMBER 3. PAGEISEQUENTIAL I REVISIONYEAR j NUMBER INUMBERMcGuire Nuclear Station, Unit 2 05000370 2015 00 5 OF 517. NARRATIVESAFETY ANALYSIS:At the time of the CA system actuation, the CF system was shut down and the CA system was supplyingfeedwater to the SGs. No actual loss of feedwater occurred. The plant was returning from a refuelingoutage with low decay heat level due to the extended shutdown and new fuel in the reactor. Decay heatremoval using the SGs was not challenged. The signal (trip of all CF pumps) that caused the CA actuationwas not required to be operable in Mode 4. The signal is required by TS 3.3.2 to be operable in Modes 1-3only.In conclusion, this event is Considered to be of low safety significance. The CA system responded asdesigned. This event was of no significance to the health and safety of the public.ADDITIONAL IN FORMATION:A three year search of the McGuire corrective action database revealed no other CA actuation eventsresulting from a latent procedural deficiency. Therefore, this event is not recurring.This event is not considered to constitute a Safety System Functional Failure. This event only involved theactuation of the CA System. It was determined through the extent of condition review that the conditiondescribed in this LER affects both CA Trains on both units. The planned action will address the extent ofcondition. There was no release of radioactive material, radiation overexposure, or personnel injuryassociated with the event described in this LER.}}

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