Part 21 Report - 1998-590

LICENSEE: ROCHESTER GAS & ELECTRIC CORP. SITE: GINNA 1 EN NUMBER:34632 DOCKET: 05000244 EVENT DATE: 07-27-98 RX TYPE: PWR EVENT TIME: 12:00 VENDORS: W-2-LP NOTIFY DATE: 08-12-98 EMERGENCY CLASS: N/A REGION: 1 STATE: NY TIME: 14:10 OPS OFFICER: DICK JOLLIFFE 10 CFR SECTION: CDEG 21.21(c)(3)(i) DEFECTS/NONCOMPLIANCE UNIT SCRAM RX INIT INITIAL MODE CURR CURRENT MODE CODE CRIT PWR PWR 1 N Y 100 POWER OPERATION 100 POWER OPERATION 10CFR21 - WESTINGHOUSE DB-75 CIRCUIT BREAKERS WITH MISSING TRIPPER BAR TABS THERE ARE SIX WESTINGHOUSE DB-75 CIRCUIT BREAKERS INSTALLED AT GINNA IN SAFEGUARDS BUSES #14 AND #16 AND ONE UNINSTALLED SAFETY RELATED SPARE. ON 03/25/98, DURING TROUBLESHOOTING ACTIVITIES, THE LICENSEE DISCOVERED THAT THE CENTER TRIPPER BAR TABS WERE MISSING FROM A WESTINGHOUSE DB-75 CIRCUIT BREAKER INSTALLED IN THE 'B' EMERGENCY DIESEL GENERATOR (EDG) SUPPLY CIRCUIT BREAKER TO THE CLASS 1E SAFETY RELATED BUS #16 AT GINNA. PRIOR TO 03/25/98, GINNA MAINTENANCE TECHNICIANS HAD RETROFIT THE 'B' EDG DB-75 SUPPLY CIRCUIT BREAKER WITH AN AMPTECTOR SOLID STATE TRIP UNIT PER WESTINGHOUSE INSTRUCTION I.B. 33-850-6 THAT INSTRUCTED THE TECHNICIANS TO REMOVE ALL TRIPPER BAR TABS FROM THE TRIPPER BAR. SUBSEQUENTLY, THE WESTINGHOUSE INSTRUCTION BULLETIN WAS REVISED TO SPECIFICALLY LEAVE THE CENTER TRIPPER BAR TAB INSTALLED. THERE WERE NO WESTINGHOUSE NOTIFICATIONS TO GINNA TO REINSTALL THE CENTER TRIPPER BAR TABS ON PREVIOUSLY MODIFIED DB-75 CIRCUIT BREAKERS. THE ABSENCE OF THE CENTER TRIPPER BAR TAB ALLOWED TWO TRIPPER BAR BUSHINGS TO FALL FROM THEIR HOUSING AND IS BELIEVED, OVER TIME, TO HAVE BENT THE TRIPPER BAR SO THAT IT WOULD NOT FULLY RESET. THE FAILURE OF THE TRIPPER BAR TO FULLY RESET CAUSED THE INTERMITTENT FAILURE TO CLOSE ON THE DB-75 'B' EDG SUPPLY CIRCUIT BREAKER TO BUS #16. WITH THE IDENTIFIED DEFICIENCY IN THE 'B' EDG SUPPLY CIRCUIT BREAKER, IT IS POSSIBLE THAT A SINGLE FAILURE COULD RENDER BOTH SAFETY TRAINS INCAPABLE OF PERFORMING THEIR SAFETY FUNCTIONS (BUSES #14 AND #16). THIS DEFICIENCY CONSTITUTES A SUBSTANTIAL SAFETY HAZARD. BETWEEN MAR 85 AND FEB 88, THE DB-75 'B' EDG SUPPLY CIRCUIT BREAKER WAS INSTALLED WITH THE INCORRECT MODIFICATION. IN FEB 88, THE DB-75 CIRCUIT BREAKER INSTALLED IN THE 'A' EDG SUPPLY BREAKER ON BUS #14 WAS INCORRECTLY MODIFIED IN THE SAME MANNER AS THE 'B' EDG SUPPLY CIRCUIT BREAKER. BETWEEN FEB 88 AND MAY 96, BOTH EDG OUTPUT CIRCUIT BREAKERS TO BUSES #14 AND #16 WERE INSTALLED WITH THE INCORRECT MODIFICATIONS. IN MAY 96, THE ORIGINAL SPARE DB-75 CIRCUIT BREAKER, #96-04, WAS INSTALLED IN THE 'A' EDG SUPPLY BREAKER POSITION. CIRCUIT BREAKER #96-04 HAD BEEN MODIFIED CORRECTLY PER THE CURRENT REVISION OF THE WESTINGHOUSE INSTALLATION INSTRUCTIONS PRIOR TO BEING INSTALLED INTO THE 'A' EDG SUPPLY CIRCUIT BREAKER POSITION. ON 03/25/98, THE LICENSEE INSPECTED ALL WESTINGHOUSE DB-75 CIRCUIT BREAKERS AT GINNA. PLANT MAINTENANCE TECHNICIANS INSTALLED CENTER TRIPPER BAR TABS ON THE 'B' EDG SUPPLY CIRCUIT BREAKER AND THE SPARE CIRCUIT BREAKER, PREVIOUSLY INSTALLED IN THE 'A' EDG SUPPLY CIRCUIT BREAKER POSITION. THE DB-75 CIRCUIT BREAKERS ON BUSES #14 AND #16 AND THE TWO BUS TIE CIRCUIT BREAKERS BETWEEN BUSES #14 AND #16 HAD BEEN CORRECTLY MODIFIED PER THE REVISED WESTINGHOUSE INSTRUCTIONS. ALTHOUGH THE POTENTIAL FOR FAILURE EXISTED AT GINNA, THE WESTINGHOUSE DB-75 CIRCUIT BREAKERS WERE TESTED WITH REGULAR SURVEILLANCE TESTS TO PROVE OPERABILITY AND THE FAILURE MECHANISM IS OF THE NATURE THAT DEGRADES OVER TIME. THE MISSING TRIPPER BAR TAB WOULD NOT IMMEDIATELY FAIL THE CIRCUIT BREAKER UPON REMOVAL. LICENSEE NUCLEAR ENGINEERING PERSONNEL ARE PERFORMING A VENDOR DOCUMENT REVIEW TO VERIFY THAT ALL WESTINGHOUSE DB-75 CIRCUIT BREAKERS ARE PROPERLY CONFIGURED IN ACCORDANCE WITH APPLICABLE VENDOR DOCUMENTATION. ALL LICENSEE CORRECTIVE ACTIONS ARE SCHEDULED TO BE COMPLETED BY 12/31/98. ON 03/25/98, THE LICENSEE DISTRIBUTED A NOTIFICATION OF THIS CONDITION TO INDUSTRY REPRESENTATIVES. THE CENTER TRIPPER BAR TAB INSTALLATION CAN BE VERIFIED BY VISUAL INSPECTION, POSSIBLY WHILE THE CIRCUIT BREAKER IS IN SERVICE. SPECIFIC INFORMATION FOR THIS REPORT WAS OBTAINED DURING DISCUSSIONS WITH WESTINGHOUSE REPRESENTATIVES ON 07/27/98. THE LICENSEE PLANS TO SUBMIT A WRITTEN 10CFR21 REPORT OF THIS CONDITION TO THE NRC BY 09/11/98.

Page Last Reviewed/Updated Friday, January 31, 2020