U.S. Nuclear Regulatory Commission Operations Center Event Reports For 11/01/94 - 11/02/94 ** EVENT NUMBERS ** 27951 27971 27972 !!!!!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED !!!!!!! +----------------------------------+ +-----------------------+ |POWER REACTOR | |EVENT NUMBER: 27951 | +----------------------------------+ +-----------------------+ +------------------------------------------------+-----------------------------+ |FACILITY: POINT BEACH REGION: 3 |NOTIFICATION DATE: 10/26/94 | |UNIT: [1] [ ] [ ] STATE: WI |NOTIFICATION TIME: 15:17 [ET]| |RX TYPE: [1] W-2-LP,[2] W-2-LP |EVENT DATE: 10/26/94 | +------------------------------------------------+EVENT TIME: 11:00[CDT]| |NRC NOTIFIED BY: RINZEL |LAST UPDATE DATE: 11/01/94 | |HQ OPS OFFICER: TIM McGINTY +-----------------------------+ +------------------------------------------------+ NOTIFICATIONS | |EMERGENCY CLASS: NOT APPLICABLE +-----------------------------+ |10 CFR SECTION: |L. ROBERT GREGER RDO | |AIND 50.72(b)(2)(iii)(D) ACCIDENT MITIGATION | | | | | | | | | | | | | | +-----+----------+-------+--------+--------------+--+--------+-----------------+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-----------------+ | 1 | N Y 100 POWER OPERATION | 100 POWER OPERATION | | | | | | | | | +-----+---------------------------------------------+--------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | PROBLEM WITH THE CALIBRATED RANGES OF THE T-hot AND T-cold RTD's FOUND. | | | | DURING ACCIDENT ANALYSIS EVALUATIONS THAT WESTINGHOUSE IS PERFORMING IN | | SUPPORT OF THE POTENTIAL UNIT 2 REACTOR COOLANT SYSTEM FLOW RATE CHANGES | | (DUE TO STEAM GENERATOR TUBE PLUGGING), A SEPARATE PROBLEM WAS DISCOVERED. | | THE PROBLEM RELATES TO THE OVER-POWER DELTA T (OPdT) SETPOINTS. THE | | CURRENT CALIBRATED RANGES OF THE T-hot AND T-cold RTD's ARE NOT WHAT IS | | ASSUMED IN THE ACCIDENT ANALYSIS. THE RESULT IS THE OPdT FUNCTION DOES NOT | | PROVIDE ADEQUATE PROTECTION UNDER A SLOW REACTIVITY ADDITION (ROD | | WITHDRAWAL) TRANSIENT INITIATED FROM ABOUT 10% POWER TO A POWER LEVEL OF | | ABOUT 90%. THE CONDITION IS MOST LIMITING AT BEGINNING OF LIFE. | | | | THE CONDITION APPLIES TO BOTH UNITS, HOWEVER, UNIT 2 IS IN A REFUELING | | OUTAGE AT THIS TIME. UNIT 1 IS CURRENTLY AT 100% POWER, AND THEREFORE | | COMPLETE PROTECTION IS IN PLACE AT THAT POWER LEVEL. THE LICENSEE STAFF IS | | PURSUING A JUSTIFICATION FOR CONTINUED OPERATION AND FURTHER DETAILED | | EVALUATIONS WITH WESTINGHOUSE. | | | | THE LICENSEE HAS INFORMED THE RESIDENT INSPECTOR. | | | | ***RETRACTION @ 1234ET 11/01/94 BY BRIAN McLean TAKEN BY MACKINNON*** | | | | LICENSEE IS RETRACTING THIS EVENT BECAUSE IT HAS BEEN DETERMINED THAT | | T-cold and T-hot RTDs ARE IN CALIBRATION OVER THEIR REQUIRED RANGES AND ARE | | CAPABLE OF PERFORMING THEIR ACCIDENT MITIGATION FUNCTION. R3DO (ROGER | | LANKSBURY) NOTIFIED. THE RESIDENT INSPECTOR WAS INFORMED BY THE LICENSEE. | +------------------------------------------------------------------------------+ +----------------------------------+ +-----------------------+ |POWER REACTOR | |EVENT NUMBER: 27971 | +----------------------------------+ +-----------------------+ +------------------------------------------------+-----------------------------+ |FACILITY: COOPER REGION: 4 |NOTIFICATION DATE: 11/01/94 | |UNIT: [1] [ ] [ ] STATE: NE |NOTIFICATION TIME: 18:06 [ET]| |RX TYPE: [1] GE-4 |EVENT DATE: 11/01/94 | +------------------------------------------------+EVENT TIME: 15:15[CST]| |NRC NOTIFIED BY: STEVE SMALLFOOT |LAST UPDATE DATE: 11/01/94 | |HQ OPS OFFICER: JOHN MacKINNON +-----------------------------+ +------------------------------------------------+ NOTIFICATIONS | |EMERGENCY CLASS: NOT APPLICABLE +-----------------------------+ |10 CFR SECTION: |DALE POWERS RDO | |ADAS 50.72(b)(2)(i) DEG/UNANALYZED COND | | | | | | | | | | | | | | +-----+----------+-------+--------+--------------+--+--------+-----------------+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-----------------+ | 1 | N N 0 COLD SHUTDOWN | 0 COLD SHUTDOWN | | | | | | | | | +-----+---------------------------------------------+--------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | MINIMUM DESIGN RIVER LEVEL ASSUMED IN USFAR HAS BEEN INVALIDATED BY SILTING | | IN THE RIVER. | | | | LICENSEE DETERMINED THAT THE MINIMUM DESIGN RIVER LEVEL ASSUMED IN THE | | USFAR AND AS REFLECTED IN PLANT PROCEDURES HAD BEEN INVALIDATED BY SILTING | | IN THE RIVER. ALSO A GUIDE\WEIR WALL WAS INSTALLED IN 1974 IN FRONT OF THE | | INTAKE STRUCTURE. THE WEIR WALL BASE IS AT 865 FEET, WHICH REQUIRES THAT | | THE RIVER FLOW AROUND AND INTO THE INTAKE STRUCTURE. THE USFAR STATES THAT | | THE MAXIMUM RIVER LOW ELEVATION IS 865 FEET FOR SAFE PLANT OPERATION. | | RECENT SURVEYS OF THE RIVER BOTTOM INDICATED THAT SILTING OF THE RIPRAP ON | | THE SOUTHERN END HAD EXCEEDED 865 FEET. THE WEIR WALL CONSTRUCTED IN 1974 | | IN FRONT OF THE INTAKE STRUCTURE ALSO EXCEEDS THE 865 ELEVATION, THUS AT | | MINIMUM RIVER LEVELS SUFFICIENT WATER WOULD NOT HAVE BEEN AVAILABLE TO | | PROVIDE THE REQUIRED NPSH FOR THE SERVICE WATER PUMPS. COMPENSATORY ACTIONS | | IN PLANT PROCEDURES ARE BASED ON AN ELEVATION OF 865 FEET. | | THE SOUTHERN END OF THE INTAKE STRUCTURE HAS BEEN DREDGED TO LOWER THE | | BOTTOM TO APPROXIMATELY 862 FEET, ENSURING OPERABILITY OF THE SERVICE WATER | | SYSTEM. ADDITIONAL CHANGES ARE BEING INVESTIGATED TO PROVIDE ADDITIONAL | | MARGIN. THE RIVER ELEVATION IS CURRENTLY 881 FEET 9 INCHES. | | | | RESIDENT INSPECTOR WAS INFORMED BY THE LICENSEE. | +------------------------------------------------------------------------------+ +----------------------------------+ +-----------------------+ |POWER REACTOR | |EVENT NUMBER: 27972 | +----------------------------------+ +-----------------------+ +------------------------------------------------+-----------------------------+ |FACILITY: GRAND GULF REGION: 2 |NOTIFICATION DATE: 11/01/94 | |UNIT: [1] [ ] [ ] STATE: MS |NOTIFICATION TIME: 22:09 [ET]| |RX TYPE: [1] GE-6 |EVENT DATE: 11/01/94 | +------------------------------------------------+EVENT TIME: 20:20[CST]| |NRC NOTIFIED BY: W CADE |LAST UPDATE DATE: 11/01/94 | |HQ OPS OFFICER: JOHN MacKINNON +-----------------------------+ +------------------------------------------------+ NOTIFICATIONS | |EMERGENCY CLASS: NOT APPLICABLE +-----------------------------+ |10 CFR SECTION: |MARK LESSER RDO | |ARPS 50.72(b)(2)(ii) RPS ACTUATION | | | | | | | | | | | | | | +-----+----------+-------+--------+--------------+--+--------+-----------------+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-----------------+ | 1 | A/R Y 100 POWER OPERATION | 0 HOT SHUTDOWN | | | | | | | | | +-----+---------------------------------------------+--------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | REACTOR SCRAMMED FOR UNKNOWN REASON DURING PERFORMANCE OF DIVISION 1 | | REACTOR HIGH PRESSURE RPS SURVEILLANCE TESTING. | | | | I&C WERE PERFORMING DIVISION 1 REACTOR HIGH PRESSURE RPS SURVEILLANCE TEST | | (QUARTERLY TEST) WHEN A FULL REACTOR SCRAM OCCURRED. ALL RODS FULLY | | INSERTED INTO THE CORE. TURBINE BYPASS CONTROL SYSTEM OPERATED PROPERLY (NO | | SRVs OPENED & REACTOR VESSEL DID NOT GO LOW ENOUGH TO AUTO START HPCS & | | RCIC). REACTOR TEMPERATURE , PRESSURE (537 DEGREES F & 952 PSI) AND WATER | | LEVEL IS BEING MAINTAINED BY THE TURBINE BYPASS CONTROL SYSTEM AND | | FEEDWATER IN THE STARTUP LEVEL CONTROL MODE OF OPERATION. | | AFTER THE REACTOR SCRAM LICENSEE HAD PROBLEMS WITH SOME OF THEIR FEEDWATER | | HEATER STRINGS ISOLATING. REACTOR OPERATOR TOOK MANUAL CONTROL OF FEEDWATER | | TO CONTROL REACTOR VESSEL WATER LEVEL (LOWEST REPORTED REACTOR VESSEL WATER | | WAS -15", LEVEL TWO IS -42.6"). DURING MANUAL CONTROL OF THE FEEDWATER | | CONTROL SYSTEM REACTOR VESSEL WATER LEVEL INCREASED TO +53" AT WHICH POINT | | REACTOR FEEDWATER PUMP "A" TRIPPED (SHOULD TRIP AT +54" WHICH IS HIGH | | REACTOR VESSEL WATER LEVEL). ALL OTHER SYSTEMS OPERATED PROPERLY. ALL | | EMERGENCY CORE COOLING SYSTEMS, AND THEIR EMERGENCY DIESEL GENERATORS ARE | | FULLY OPERABLE IF NEEDED. | | LICENSEE IS INVESTIGATING THE CAUSE OF THE REACTOR SCRAM. | | | | RESIDENT INSPECTOR WAS INFORMED BY THE LICENSEE. | +------------------------------------------------------------------------------+