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Event Notification Report for April 21, 1999

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           04/20/1999 - 04/21/1999

                              ** EVENT NUMBERS **

35609  35610  35611  

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|Power Reactor                                    |Event Number:   35609       |
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| FACILITY: POINT BEACH              REGION:  3  |NOTIFICATION DATE: 04/20/1999|
|    UNIT:  [1] [2] []                STATE:  WI |NOTIFICATION TIME: 15:39[EDT]|
|   RXTYPE: [1] W-2-LP,[2] W-2-LP                |EVENT DATE:        04/20/1999|
+------------------------------------------------+EVENT TIME:        13:53[CDT]|
| NRC NOTIFIED BY:  R. HASTING                   |LAST UPDATE DATE:  04/20/1999|
|  HQ OPS OFFICER:  JOHN MacKINNON               +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |MELVYN LEACH         R3      |
|10 CFR SECTION:                                 |                             |
|AOUT 50.72(b)(1)(ii)(B)  OUTSIDE DESIGN BASIS   |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          Y       100      Power Operation  |100      Power Operation  |
|2     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| Postulated fire in the Auxiliary Feedwater room could affect diesel power to |
| Safe Shutdown Equipment.                                                     |
|                                                                              |
| For a postulated fire in the north half of the Auxiliary Feed Water (AFW)    |
| Pump Room, the G-0l Diesel Generator is relied upon to provide emergency     |
| diesel power to Safe Shutdown Equipment.  Without the fuel oil pump, there   |
| will only be enough fuel in the day tanks to run the diesel for 4 hours.     |
| This will not support maintaining Hot Shutdown of the units. The G-02 Diesel |
| Generator will not be available due to loss of ventilation to the G-02       |
| Diesel Room for room exhaust fan cables being located in the north half of   |
| the AFW Pump Room. The G-03 or G-04 Diesel Generators will not be available  |
| due to the potential loss of control circuitry and power feeds to            |
| transformers 1X-14 and 2X-14 being located in the north half of the AFW Pump |
| Room as well.                                                                |
|                                                                              |
| The primary significance of this scenario is that in order to insure the     |
| proper Appendix R equipment is available for a fire in the north half of the |
| AFW Pump Room the 1A-05 bus must have power.  Provisions must be made to     |
| maintain G-01 as that supply source or qualify another source such as G-05   |
| Gas Turbine. Without G-01 availability, this places the plant outside of     |
| design basis for Appendix R.                                                 |
|                                                                              |
| Compensatory actions at this time are twice per shift (8 hour shift)         |
| Appendix R fire inspections.                                                 |
|                                                                              |
| The licensee is looking into using the Gas Turbine, G-05,  or locally        |
| starting the G-03 Diesel Generator.                                          |
|                                                                              |
| The NRC Resident Inspector will be informed of this notification by the      |
| licensee.                                                                    |
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|Power Reactor                                    |Event Number:   35610       |
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| FACILITY: COOK                     REGION:  3  |NOTIFICATION DATE: 04/20/1999|
|    UNIT:  [1] [2] []                STATE:  MI |NOTIFICATION TIME: 18:17[EDT]|
|   RXTYPE: [1] W-4-LP,[2] W-4-LP                |EVENT DATE:        04/20/1999|
+------------------------------------------------+EVENT TIME:        16:14[EDT]|
| NRC NOTIFIED BY:  BRIAN MUTZ                   |LAST UPDATE DATE:  04/20/1999|
|  HQ OPS OFFICER:  DICK JOLLIFFE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |MELVYN LEACH         R3      |
|10 CFR SECTION:                                 |                             |
|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          N       0        Cold Shutdown    |0        Cold Shutdown    |
|2     N          N       0        Cold Shutdown    |0        Cold Shutdown    |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| - Aux Bldg Vent Systems may not meet their safety and accident mitigation    |
| function during accident conditions -                                        |
|                                                                              |
| The licensee reviewed the Auxiliary Building Ventilation Systems as part of  |
| the Expanded System Readiness Reviews (ESRRs).  The scope of the ventilation |
| review included the Engineered Safety Features (ESF) Ventilation, known as   |
| Auxiliary Equipment Subsystem (AES), which is the focus for this report.     |
|                                                                              |
| The AES safety and accident mitigation function is to provide sufficient     |
| cooling to the general areas and safety related equipment rooms required to  |
| operate during accident conditions for multiple safety related systems,      |
| including Component Cooling Water System, Containment Spray System, Residual |
| Heat Removal System, Charging System, and Safety Injection System.           |
|                                                                              |
| As a result of the ESRR, it has been concluded that currently there is       |
| insufficient assurance that the AES is capable of meeting its safety and     |
| accident mitigation function for temperature control of the Auxiliary        |
| Building in its present configuration.  This conclusion is based on          |
| significant errors that were identified in ventilation related temperature   |
| calculations for the Auxiliary Building, combined with the small margin that |
| previously existed between calculated results and design requirements, such  |
| that there is little assurance of adequate auxiliary building room cooling   |
| for ESF equipment.  In addition, the AES dampers are not single failure      |
| proof (as previously reported) and the system lacks missile protection       |
| between trains.                                                              |
|                                                                              |
| Both units are currently in Operational Mode 5 (Cold Shutdown).  Priority    |
| evaluation of these issues, including determination of the need for physical |
| modifications, is ongoing and will be resolved prior to startup of the       |
| units.                                                                       |
|                                                                              |
| The licensee notified the NRC Resident Inspector.                            |
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|Power Reactor                                    |Event Number:   35611       |
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| FACILITY: LIMERICK                 REGION:  1  |NOTIFICATION DATE: 04/20/1999|
|    UNIT:  [1] [] []                 STATE:  PA |NOTIFICATION TIME: 19:21[EDT]|
|   RXTYPE: [1] GE-4,[2] GE-4                    |EVENT DATE:        04/20/1999|
+------------------------------------------------+EVENT TIME:        18:32[EDT]|
| NRC NOTIFIED BY:  RAY McKINLEY                 |LAST UPDATE DATE:  04/21/1999|
|  HQ OPS OFFICER:  DICK JOLLIFFE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |MOHAMED SHANBAKY     R1      |
|10 CFR SECTION:                                 |CURT COWGILL         R1      |
|ACCS 50.72(b)(1)(iv)     ECCS INJECTION         |RANDY BLOUGH         R1      |
|ARPS 50.72(b)(2)(ii)     RPS ACTUATION          |DON FLOREK           R1      |
|AESF 50.72(b)(2)(ii)     ESF ACTUATION          |ART BURRITT          SRI     |
|                                                |WILLIAM BATEMAN      NRR     |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|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     |
|                                                   |                          |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| - AUTO REACTOR SCRAM FROM 100% POWER DUE TO LOSS OF MAIN FEEDWATER; ECCS     |
| INJECTION -                                                                  |
|                                                                              |
| AT 1832 ON 04/20/99, WITH UNIT 1 AT 100% POWER, ALL EIGHT CONDENSATE SYSTEM  |
| DEEP BED DEMINERALIZER OUTLET MOTOR OPERATED VALVES FAILED CLOSED POSSIBLY   |
| DUE TO A COMPUTER MALFUNCTION.  THE DEMINERALIZER BYPASS VALVES TRIPPED DUE  |
| TO THERMAL OVERLOADS AND FAILED TO OPEN, CAUSING ALL THREE STEAM DRIVEN MAIN |
| FEEDWATER PUMPS TO TRIP.  THE REACTOR VESSEL WATER LEVEL DROPPED FROM A      |
| NORMAL LEVEL OF +35 INCHES TO +12.5 INCHES, CAUSING THE REACTOR TO           |
| AUTOMATICALLY SCRAM FROM 100% POWER DUE TO LOW REACTOR VESSEL WATER LEVEL.   |
| ALL CONTROL RODS INSERTED COMPLETELY; HOWEVER, ROD #30-39 INSERTED SLOWLY.   |
| NO SAFETY/RELIEF VALVES LIFTED.  STEAM IS BEING DUMPED TO THE MAIN           |
| CONDENSER.                                                                   |
|                                                                              |
| REACTOR VESSEL WATER LEVEL FURTHER DROPPED TO -38 INCHES, CAUSING THE HIGH   |
| PRESSURE COOLANT INJECTION (HPCI)  AND THE REACTOR CORE ISOLATION COOLING    |
| (RCIC) SYSTEMS TO ACTUATE AND INJECT INTO THE REACTOR VESSEL.  THE REDUNDANT |
| REACTIVITY CONTROL SYSTEM INITIATED TO TRIP THE CIRCUIT BREAKERS FOR THE     |
| REACTOR RECIRCULATION PUMPS.  PRIMARY CONTAINMENT ISOLATION SYSTEM GROUPS    |
| 1B, 2A, 2B, 2C, 3, 6A, 6B, 6C, 7B, AND 8B ISOLATED.  THE DIVISION 'A'        |
| ATWS/RPT CIRCUIT BREAKER FOR THE 'A' RECIRC MOTOR GENERATOR SET FAILED TO    |
| TRIP, AS REQUIRED.  SMOKE WAS OBSERVED TO BE COMING FROM THE BREAKER.  THE   |
| BREAKER WAS MANUALLY TRIPPED FROM THE CONTROL ROOM AND THE SMOKING STOPPED.  |
| THE 'A' AND 'B' RECIRC MOTOR GENERATOR SET DRIVE MOTOR CIRCUIT BREAKERS ALSO |
| FAILED TO TRIP ON THE 13 kV BUS FAST TRANSFER.  THE BREAKERS WERE MANUALLY   |
| TRIPPED.                                                                     |
|                                                                              |
| REACTOR VESSEL WATER LEVEL DROPPED TO A LOW LEVEL OF -75 INCHES ABOUT 40     |
| SECONDS INTO THE EVENT (TOP OF ACTIVE FUEL IS  -161 INCHES).  THE HPCI AND   |
| RCIC SYSTEMS RECOVERED REACTOR VESSEL WATER LEVEL TO +25 INCHES, AT WHICH    |
| TIME CONTROL ROOM OPERATORS MANUALLY SECURED THE HPCI SYSTEM.  THE RCIC      |
| SYSTEM IS MAINTAINING REACTOR VESSEL WATER LEVEL AT +25 INCHES WITH REACTOR  |
| PRESSURE AT 875 PSIG AT AN INJECTION RATE OF 300 GPM.                        |
|                                                                              |
| PLANT OPERATORS ENCOUNTERED A PROBLEM WITH THE AUXILIARY STEAM SYSTEM AND    |
| THE MECHANICAL VACUUM PUMP.  THEY MANUALLY CLOSED THE MAIN STEAM ISOLATION   |
| VALVES.  THEY ARE CONTROLLING REACTOR VESSEL WATER LEVEL WITH THE RCIC       |
| SYSTEM AND REACTOR COOLANT SYSTEM PRESSURE WITH THE HPCI SYSTEM.             |
|                                                                              |
| UNIT 1 IS STABLE IN OPERATIONAL CONDITION 3 (HOT SHUTDOWN) AND COOLING DOWN  |
| TO COLD SHUTDOWN.  PRIMARY CONTAINMENT PARAMETERS ARE NORMAL.  THERE WAS NO  |
| RELEASE OF RADIOACTIVE MATERIAL.  RELEASE RATES ARE NORMAL.  THIS EVENT HAD  |
| NO IMPACT ON UNIT 2 WHICH IS IN OPERATIONAL CONDITION 5 IN A REFUELING       |
| OUTAGE.                                                                      |
|                                                                              |
| THE LICENSEE NOTIFIED THE NRC RESIDENT INSPECTOR AND IS INVESTIGATING THIS   |
| EVENT.  THEY PLAN TO ISSUE A PRESS RELEASE.                                  |
|                                                                              |
| *** UPDATE ON 4/21/99 @ 0418 BY HUNTER TO GOULD ***                          |
|                                                                              |
| THE REACTOR IS IN OPCON 3 AT 350 PSIG CONTINUING TO COLD SHUTDOWN.           |
| CONDENSER VACUUM IS BEING REESTABLISHED IN ORDER TO RE-OPEN THE MSIVs AND    |
| SECURE HPCI FROM PRESSURE CONTROL MODE.  FEEDWATER SYSTEM IS BEING           |
| REPRESSURIZED TO REESTABLISH NORMAL FEED AND SECURE RCIC FROM LEVEL CONTROL  |
| MODE.                                                                        |
|                                                                              |
| ALSO THE "1A" AND "1B" MG SET DRIVE MOTOR BREAKERS DID NOT TRIP DURING THE   |
| TRANSIENT SINCE PLANT LOADS WERE PREVIOUSLY TRANSFERRED BY A REACTOR         |
| OPERATOR PRIOR TO THE TURBINE TRIP.  THE BREAKERS, THEREFORE, OPERATED AS    |
| DESIGNED.                                                                    |
|                                                                              |
| THE RESIDENT INSPECTOR WAS NOTIFIED.                                         |
|                                                                              |
| THE REG 1 RDO(SHANBAKY) WAS NOTIFIED.                                        |
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