ML18012A391

LER 96-018-00:on 960903,manual Reactor Trip Initiated.Caused by Mechanical Failure of B NSW Pump & a NSW Pump. Restored a Pump to Service & Performed Secondary Plant Walkdown to Support Plant re-start.W/961003 Ltr

ML18012A391
Person / Time
Site:	Harris
Issue date:	10/03/1996
From:	Donahue J, Verrilli M CAROLINA POWER & LIGHT CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
HNP-96-164, LER-96-018, LER-96-18, NUDOCS 9610100116
Download: ML18012A391 (8)

Text

CATEGORY REGUL . ORY INFORMATION DISTRIBUT N SYSTEM (RIDS) f ACCESSION NBR:9610100116 DOC.DATE: 96/10/03 NOTARIZED: NO DOCKET FACIL:50-400 Shearon Harris Nuclear Power Plant, Unit 1, Carolina 05000400 AUTH. NAME AUTHOR AFFILIATION VERRILLI,M. Carolina Power a Light Co.

DONAHUE,J.W. Carolina Power & Light Co.

RECIP.NAME RECIPIENT AFFILIATION

SUBJECT:

LER 96-018-00:on 960903,manual reactor trip initiated. Caused by mechanical "A"

failure of "B" NSW pump 6 "A" NSW pump.

Restored pump to service & performed secondary plant walkdown to support plant re-start.W/961003 ltr.

DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR / ENCL t SIZE: ( T TITLE: 50.73/50.9 Licensee Event Report (LER), incident Rpt, etc.

E NOTES:Application for permit renewal filed. 05000400 RECIPIENT COPIES RECIPIENT COPIES 0 ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD2-1 PD 1 1 LEiN 1 1 INTERNAL: C 1 1 AEOD/SPD/RRAB 2 2 Y

E CEN 1 1 NRR/DE/ECGB 1 1 NRR/DE/EELB 1 1 NRR/DE/EMEB 1 1 NRR/DRCH/HHFB 1 1 NRR/DRCH/HICB 1 . 1 NRR/DRCH/HOLB 1 1 NRR/DRCH/HQMB 1 1 NRR/DRPM/PECB 1 1 NRR/DSSA/SPLB 1 1 NRR/DSSA/SRXB 1 1 RES/DSIR/EIB 1 1 RGN2 FILE 01 1 1 D, EXTERNAL: L ST LOBBY WARD 1 1 LITCO BRYCEiJ H 1 1 0 NOAC MURPHY,G.A 1 1 NOAC POOREgW. 1 1 NRC PDR 1 1 NUDOCS FULL TXT 1 1 U

E NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTE. TO HAVE YOUR NAME OR ORGANIZATION REMOVED FROM DISTRIBUTION LISTS OR REDUCE THE NUMBER OF COPIES RECEZVED BY YOU OR YOUR ORGANIZATION, CONTACT THE DOCUMENT CONTROL DESK (DCD) ON EXTENSION 415-2083 FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 24 ENCL 24

Carolina Power R light Company Harris Nuclear Plant PO Box 165 New Hill NC 27562 OCT 8 r996 U.S. Nuclear Regulatory Commission Serial: HNP-96-164 ATTN: NRC Document Control Desk 10CFR50.73 Washington, DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 DOCKET NO. 50-400 LICENSE NO. NPF-63 LICENSEE EVENT REPORT 96-018-00 Sir or Madam:

In accordance with Title 10 to the Code of Federal Regulations, the enclosed Licensee Event Report is submitted. This report describes a manual reactor trip due to the loss of Normal Service Water.

Sincerely, J. W. Donahue Director of Site Operations Harris Plant MV Enclosure c: Mr. J. B. Brady (HNP Senior Resident - NRC)

Mr. S. D. Ebneter (NRC Regional Administrator - Region II)

Mr. N. B. Le (NRC Project Manager - NRR) 96iOiOOith 9bi003 PDR ADOCK 05000400 S PDR State Road 1134 New Hill NC

U. S. Nuclear Regulatory Commission Document Control Desk / HNP-96-164 Page 2 of 2 cc: Mr. R. T. Biggerstaff Ms. P. B. Brannan Mr. B. H. Clark Mr. J. M. Collins Mr. J. P. Cowan Mr. G. W. Davis Ms. S. F. Flynn Mr. H. W. Habermeyer Mr. G. D. Hicks (BNP)

Mr. M. D. Hill Mr. W. J. Hindman Ms. C. W. Hobbs (HEEC)

Mr. R. M. Erich (RNP)

Ms. W. C. Langston Mr. C. W. Martin (BNP)

Mr. R. D. Martin Mr. J. W. McKay Mr. P. M. Odom (RNP)

Mr. W. R. Robinson Mr. G. A. Rolfson Mr. R. F. Saunders Mr. R. S. Stancil Mr. C. N. Sweely Mr. J. P. Thompson (BNP)

Mr. T. D. Walt Mr. R. L. Warden (RNP)

HNP Real Time Training INPO Harris Licensing File Nuclear Records

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 l495) EXPIRES 04/30/9B EST)MA'TED BURDEN PER RESPONSE TO COMPLY WITH THS MANDATORY INfORMATION COLLECT)OH REDDEST. 500 HRS. REPORTED LESSONS LEARNED ARE LICENSEE EVENT REPORT (LER) INCORPORATED (NTO THE UCEHSIHG PROCESS ANO FED BACK TO INDUSTRY.

FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE IHfORMATIN AND RECORDS MANAGEMENT BRANCH Ire f33L US. NUCLEAR REGULATORY COMMISSION, (See reverse for required number of WASHUIGTON, DC 205550001, ANO TO THE PAPERWORK REDUCTNH PROJECT CI)50 digits/characters for each block) 010(L Off)CE OF MANAGEMENT AHD BUDGET, WASHINGTON, OC 205(LL FACILITY NAME (I) DOCKET NUMBER (2) PAGE (3)

Harris Nuclear Plant Unit-1 50-400 1 OF3 TITLE (4)

Manual reactor trip due to loss of Normal Service Water EVENT DATE (5) LER NUMBER (6) REPORT DATE (7) OTHER FACILITIES INVOLVED (8)

FACILITY NAME DOCKETNUMBER SEQUENTIAL REVISION MONTH OAY YEAR MONTH BAY YEAR NUMBER NUMBER 05000 FACILITY NAME DOCKET NUMBER 03 96 96 018 0 10 03 96 05000 OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR 5: (Check one o r more) (11)

MODE (9) 20.2201(b) 20.2203(a)(2)(v) 50.73(a) (2) (i) 50.73(a)(2)(viii)

POWER 20.2203(a) (1) 20.2203(a) (3) (i) 50.73(a)(2)(ii) 50.73(a)(2) (x)

LEVEL (10) 100% 20.2203(a)(2)(i) 20.2203(a)(3)(ii) 50.73(a)(2)(iii) 73.71 20.2203(a) (2) (ii) 20.2203(a) (4) 50.73(a)(2)(iv) OTHER 20.2203(a)(2)(iii) 50.36(c)(1) 50.73(a)(2)(v) Specify in Abstract below or in NRC Form 366A 20.2203(a) (2) (iv) 50.36(c) (2) 50.73(a)(2)(vii)

LICENSEE CONTACT FOR THIS LER (12)

NAME TELEPHONE NUMBER (Iociude Ares Code)

Michael Verrilli Sr. Analyst - Licensin9 (919) 362-2303 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

REPORTABLE :ig:?;E;rt REPORTABLE CAUSE SYSTEM COMPONENT MANUFACTURER CAUSE SYSTEM COMPONENT MANUFACTURER TO NPROS TO NPROS KG P115 SUPPLEMENTAL REPORT EXPECTED (14) EXPECTED MONTH OAY YEAR YES SUBMISSION X (If yes, complete EXPECTED SUBMISSION DATE). No DATE (15) 1 15 97 ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) (16)

On September 3, 1996 at approximately 2338 hours0.0271 days <br />0.649 hours <br />0.00387 weeks <br />8.89609e-4 months <br />, with the plant operating in mode 1 at 100% power and the "B" Normal Service Water (NSW) pump in service, operators in the main control room received numerous NSW system alarms and observed indication of zero flow and pressure in the NSW header. The Reactor Operator manually started the standby "A" NSW pump to restore flow, but the pump tripped after running for less than two minutes. %hen re-start attempts on the "A" NpSW pump failed, a manual reactor trip was initiated at approximately 2342 hours0.0271 days <br />0.651 hours <br />0.00387 weeks <br />8.91131e-4 months <br />. Plant systems responded as expected, mcluding an automatic start of the Auxiliary Feedwater System and the unit was stabilized in mode 3 (Hot Standby).

The cause of this event was a mechanical failure of the "B" NSW pump and the failure of the "A" NSW to remain running once manually started. The "B" NSW pump shaft sheared. The cause of the "A" NSW pump trip will require additional investigation.

Corrective actions included restoring the "A" NSW pump to service, performing a secondary plant walkdown to support plant re-start, and evaluating the acceptability of having only one NSW pump available during plant operation whfle repairs continue on the "B" NSW pump. Additional planned actions include repair of the "B" NSW pump, continuing evaluation and/or testing of the NSW system, failure analysis for the "B" NSW pump sheared shaft and incorporation of lessons learned from this event into operator training.

This event is reportable per 10CFR50.72 and 10CFR50.73. A 4-hour non-emergency report was made to the NRC at approximately 0207 via the emergency notification system.

IIIRC fORM 366A US. NUCLEAR REGULATORY COMMISSION I69GI LICENSEE EVENT REPORT (LEB)

TEXT CONTINUATION FACIUTY NAME II) OOCNET LER NUMBER IGI PAGE I3I SEOUENTIAL REYISION YEAR NUMBER NUMBER Shearon Harris Nuclear Plant - Unit //1 50400 2 OF 3 98 - 018 - 00 TEXT rsr svvsv srASvvrs svVvdvd. vsv vdiftdsvvr svrvvs vl HRC form 36QI iln EVENT DESCRIPTION:

On September 3, 1996 at approximately 2338 hours0.0271 days <br />0.649 hours <br />0.00387 weeks <br />8.89609e-4 months <br />, with the plant operating in mode 1 at 100% power and the "B" Normal Service Water pump (NSW, EIIS Code: KG-P) in service, operators in the main control room received numerous NSW system alarms and observed indication of zero flow and pressure in the NSW header. The Reactor Operator manually started the standby "A" NSW pump to restore service water fiow. After observing closed indication for the "A" NSW pump breaker and indication that the "A" NSW pump discharge valve was opening, the "B" NSW pump was secured to allow the "B" discharge valve to shut. At this time, the Reactor Operator noticed that the "A" NSW pump had tripped. Following two unsuccessful re-start attempts on the "A" NSW pump, the Unit-Senior Control Operator directed a manual reactor and turbine trip at approximately 2342 hours0.0271 days <br />0.651 hours <br />0.00387 weeks <br />8.91131e-4 months <br />. Prior to the reactor trip, the "A" Emergency Service Water (ESW) pump automatically started due to low header pressure. Plant systems responded to the reactor trip signal as expected, including an automatic start of the Auxiliary Feedwater System (EIIS Code: BA) on steam generator low-low level due to Reactor Coolant System (RCS, EIIS Code: AB) shrink following the reactor trip. The unit was stabilized in mode 3 with RCS temperature at 557 degrees and pressure at 2235 psig.

Following investigation and repairs, the plant was restarted on September 9, 1996 and returned to the grid at approximately 0342 on September 10, 1996. Delays were encountered in plant re-start due to the passage of Hurricane Fran (reference LER 96-019). Since the forced outage exceeded 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, hot rod drop testing was performed prior to reactor startup in accordance with Harris Plant's response to NRC Bulletin 96-01. Reference for hot rod drop testing results.

This event is reportable per 10CFR50.72 and 10CFR50.73 as a Reactor Protection System actuation. A 4-hour non-emergency report was made to the NRC at approximately 0207 via the emergency notification system.

CAUSE:

The cause of this event was a mechanical failure in the "B" NSW pump and a malfunction resulting in the "A" NSW pump tripping after being manually started. The "B" NSW pump experienced a sheared pump shaft. A metallurgical analysis is currently in progress to determine the failure mode. The cause of the "A" NSW pump trip is still under investigation.

SAFETY SIGNIFICANCE:

There were no safety consequences as a result of this event. The manual reactor/turbine trip was initiated per plant operating procedures to protect secondary plant components following the loss of Normal Service Water. Plant systems responded as expected following the initiation of the manual reactor/turbine trip.

PREVIOUS SIMILAR EVENTS:

Previous similar problems with the NSW pumps and discharge valves were experienced during the reactor/turbine trip that occurred on April 25, 1996, which was reported in LER 96-008. Corrective actions for that event included adjusting the mechanical latch mechanism on the "A" NSW pump discharge valve control relay (CR1/2189) to ensure that it "latched in" properly and replacing two of the "B" NSW pump discharge valve control relays (CR4/2190 &

CR1/2190) that experienced intermittent failures. Based on indications observed during the September 3, 1996 loss of NSW event, these corrective actions were effective since their associated functions performed as required. LER 96-008 also contained a corrective action to perform additional NSW testing during the next refueling outage (RFO-7).

This testing will still be performed and will incorporate the results of the investigation referenced in planned corrective action ¹2 of this LER.

NRC FORM 3BBA US. NUCLEAR REGULATORT COMMISSION l4-SB)

LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY KAME 11) COCKET LER NUMBER IB) PAGE 13)

SEOUEKTIAL RETISION TEAR NUMBER NUMBER Shearon Harris Nuclear Plant ~

Unit //1 60400 3 OF 3 96 - 018 - 00 TEXT pr moro opooo N ror)oiod. rrro oddrriool oopr'oo ol MC Form 3arrv (I 1)

CORRECTIVE ACTIONS COMPLETED:

Trouble shooting was performed which determined that a common-mode failure mechanism did not exist with the NSW pumps.

2. The "A" NSW pump was returned to service on September 7, 1996.

A safety analysis was performed on September 5, 1996, which determined the acceptability of returning the plant to service with only one NSW pump available while repairs continued on the "B" NSW pump. This analysis, combined with the results of an engineering evaluation, concluded that repairs to the "B" NSW pump could be made on-line with the "A" NSW pump in service.

A secondary plant walkdown to assess potential damage related to the loss of NSW transient was completed on September 4, 1996. Discrepancies identified during the walkdown that would prevent plant re-start were repaired on September 4, 1996.

CORRECTIVE ACTIONS PLANNED:

1. Repairs will be completed on the "B" NSW pump by November 25, 1996.

2. Additional testing and/or evaluation will be performed to determine the cause of the "A" NSW pump trip after being manually started on September 3, 1996. This will be completed during the next refueling outage (RFO-7) scheduled to start in March 1997.

3. Additional analysis will be performed to determine the failure mechanism involved in the "B" NSW pump sheared shaft. This will be completed by November 30, 1996.

4. Upon completion of the on-going investigations, training on the lessons learned from the loss of NSW event will be incorporated into the operator training program. This will be completed by November 30, 1996.

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