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SEQUOYAH 1 2 28206 01-03-95 POW LICENSEE: TENNESSEE VALLEY AUTHORITY SITE: SEQUOYAH 1 2 EN NUMBER:28206 DOCKET: 05000327 05000328 EVENT DATE: 01-03-95 RX TYPE: PWR PWR EVENT TIME: 04:21 VENDORS: W-4-LP W-4-LP NOTIFY DATE: 01-03-95 EMERGENCY CLASS: UNU REGION: 2 STATE: TN TIME: 05:15 OPS OFFICER: JOHN MacKINNON 10 CFR SECTION: AUNA 50.72(b)(1)(ii)(A) UNANALYZED COND OP AAEC 50.72(a)(1)(i) EMERGENCY DECLARED NLCO TECH SPEC LCO A/S UNIT SCRAM RX INIT INITIAL MODE CURR CURRENT MODE CODE CRIT PWR PWR 1 N Y 100 POWER OPERATION 100 POWER OPERATION 2 N Y 100 POWER OPERATION 100 POWER OPERATION LATCHES (TWO LATCHES ONE IN UPPER RIGHT HAND SIDE OF THE CUBICLE AND THE OTHER LATCH IN THE UPPER LEFT HAND SIDE OF THE CUBICLE) WHICH HOLDS BREAKER IN ITS COMPARTMENT FOUND TO BE UNLATCHED. WHILE PERFORMING CONTROL BOARD WALKDOWN FOR UNIT 2 THE ONCOMING SENIOR REACTOR OPERATOR (SRO) DISCOVERED THAT 2-FCV-63-8, A SAFETY RELATED VALVE (USED TO SUPPLY SUCTION FROM CONTAINMENT SUMP TO HIGH & INTERMEDIATE HEAD SAFETY INJECTION PUMPS AFTER REFUELING WATER STORAGE TANK LEVEL GETS LOW), HAD NO INDICATION OF VALVE POSITION. THE UNIT OPERATOR REPLACED THE LIGHT BULB AND THE 480V BREAKER WAS VERIFIED CLOSED, BUT THERE WAS STILL NO INDICATION OF THE VALVE POSITION. A SRO WAS DISPATCHED TO THE BREAKER. THE SRO VERIFIED THE FUSES WERE GOOD. WHILE CHECKING THE FUSES THE BREAKER IN ITS COMPARTMENT BEGAN TO MOVE AND THE SRO NOTICED THE LOCAL INDICATING LIGHT FOR THE BREAKER FLICKERED. THE SRO PUSHED THE BREAKER SNUGLY INTO ITS COMPARTMENT UNTIL IT WAS FULLY LATCHED AND VERIFIED BREAKER HAD PROPER INDICATION. THE VALVE, INDICATED CLOSED AT THE BREAKER COMPARTMENT AND REMOTELY IN THE MAIN CONTROL ROOM. IT WAS SUBSEQUENTLY DETERMINED THAT THIS VALVE WOULD NOT HAVE OPERATED AND THE ACTIONS OF LCO 3.5.2 WAS ENTERED AND EXITED DUE TO "A" TRAIN OF ECCS BEING INOPERABLE. A COMPLETE CONTROL BOARD WALKDOWN WAS PERFORMED AND NO OTHER SAFETY RELATED VALVES WERE FOUND WITHOUT POSITION INDICATION. FURTHER INVESTIGATION OF WHY THE BREAKER WAS NOT FULLY ENGAGED REVEALED THE "COMPARTMENT RETENTION LATCH - TWO FOR EACH BREAKER" WAS NOT FULLY ENGAGED. THE SHIFT OPERATING SUPERVISOR DIRECTED ALL 480V MOLDED CASE BREAKERS TO BE CHECKED FOR SIMILAR CONDITION. NUMEROUS BREAKERS WERE FOUND TO BE IN AN UNLATCHED OR PARTIALLY UNLATCHED (ONE OF THE TWO LATCHES UNLATCHED) CONDITION, AND THESE BREAKERS WERE CORRECTED ON THE SPOT DUE TO THE POTENTIAL FOR THESE BREAKERS TO BE IN AN UNLATCHED CONDITION AND BECOME DISENGAGED, AND THE POSSIBILITY OF BOTH TRAINS OF THE ESF EQUIPMENT TO BE INOPERABLE AT THE SAME TIME. LICENSEE DETERMINED THAT THEY WERE IN AN UNANALYZED CONDITION. LICENSING AND NUCLEAR ENGINEERING WERE CONSULTED OF THIS CONDITION. LICENSEE SAID THAT THEY STILL CHECKING BREAKERS AT THIS TIME FOR UNIT 1 AND UNIT 2. ****UPDATE 0538EST 01/03/95 BY BILL HARRIS TAKEN BY MACKINNON**** LICENSEE UPGRADED THIS EVENT TO AN UNUSUAL EVENT CLASSIFICATION PER THEIR RADIOLOGICAL EMERGENCY PLANS "HU15" (CONDITIONS THAT WARRANT INCREASED AWARENESS OF PLANT OPERATING STAFF). LICENSEE CONSIDERS THIS A SEISMIC CONCERN TO THE PLANT IN THAT IF THEY HAD A SEISMIC EVENT AND THE BREAKERS WERE UNLATCHED THE BREAKERS COULD POSSIBLY DISENGAGE FROM THEIR POWER SOURCE AND BECOME INOPERABLE. LICENSEE WILL NOTIFY STATE AND LOCAL OFFICIALS OF THIS EVENT CLASSIFICATION. RESIDENT INSPECTOR WAS INFORMED BY THE LICENSEE OF THIS EVENT. * * * UPDATE @ 1002 ON 1/3/95 BY DENNIS DIMOPHULOS TAKEN BY WEAVER * * * THE UNUSUAL EVENT WAS TERMINATED AT 0959 EST. A COMPLETE WALKDOWN OF THE SAFETY RELATED BOARDS AND NON SAFETY RELATED BOARDS IN SEISMIC AREAS WAS COMPLETED. ALL DISCREPANCIES WERE CORRECTED ON THE SPOT, WITH THE EXCEPTION OF ONE CASE WHERE ONE OF THE TWO LATCHES WAS BROKEN. THE CAUSE OF THIS CONDITION IS UNDER INVESTIGATION. THE LICENSEE INFORMED THE NRC RESIDENT INSPECTOR. THE HOO INFORMED THE RDO (VIAS); EO (DENNIG); FEMA (SHULL) ***UPDATE AT17:17 ON 1/20/95 BY DIMOPHULOS TAKEN BY GOULD*** THE LICENSEE IS RETRACTING THIS EVENT BECAUSE FURTHER EVALUATIONS HAVE DETERMINED THAT THE BREAKERS WERE OPERABLE BECAUSE THE CABINET DOORS WERE ADEQUATE TO RESTRICT BREAKER MOVEMENT DURING A SEISMIC EVENT. THEREFORE, THE LICENSEE HAS DETERMINED THAT THIS EVENT IS NOT REPORTABLE. THE RI HAS BEEN INFORMED.