Event Notification Report for July 5, 2000
U.S. Nuclear Regulatory Commission
Operations Center
Event Reports For
07/03/2000 - 07/05/2000
** EVENT NUMBERS **
37140 37141
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|Power Reactor |Event Number: 37140 |
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| FACILITY: FITZPATRICK REGION: 1 |NOTIFICATION DATE: 07/03/2000|
| UNIT: [1] [] [] STATE: NY |NOTIFICATION TIME: 11:10[EDT]|
| RXTYPE: [1] GE-4 |EVENT DATE: 07/03/2000|
+------------------------------------------------+EVENT TIME: 10:20[EDT]|
| NRC NOTIFIED BY: BERNARD HORNING |LAST UPDATE DATE: 07/03/2000|
| HQ OPS OFFICER: FANGIE JONES +-----------------------------+
+------------------------------------------------+PERSON ORGANIZATION |
|EMERGENCY CLASS: N/A |STEVEN DENNIS R1 |
|10 CFR SECTION: | |
|AESF 50.72(b)(2)(ii) ESF ACTUATION | |
| | |
| | |
| | |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1 N Y 100 Power Operation |100 Power Operation |
| | |
| | |
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EVENT TEXT
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| LOSS OF THE 'A' REACTOR PROTECTION SYSTEM BUS CAUSING MULTIPLE AUTOMATIC |
| ACTIONS |
| |
| The unit experienced a loss of 'A' reactor protection system (RPS) bus. RPS |
| motor generator output breakers opened and deenergized the bus, this caused |
| the 'A' standby gas treatment to automatically start. Also the 'A' |
| hydrogen/oxygen monitor isolation valves closed, reactor building |
| ventilation isolated, and the reactor water cleanup system tripped due to |
| isolation valve closure. |
| |
| This trip appears to be "identical" to a trip reported on 6/26/00, event |
| #37119. |
| |
| The licensee has energized the 'A' RPS bus and returned all systems to |
| normal operation with the exception of reactor water cleanup, which is being |
| restored. |
| |
| The licensee has notified the NRC Resident Inspector. |
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|Power Reactor |Event Number: 37141 |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: SUSQUEHANNA REGION: 1 |NOTIFICATION DATE: 07/04/2000|
| UNIT: [] [2] [] STATE: PA |NOTIFICATION TIME: 14:13[EDT]|
| RXTYPE: [1] GE-4,[2] GE-4 |EVENT DATE: 07/04/2000|
+------------------------------------------------+EVENT TIME: 11:54[EDT]|
| NRC NOTIFIED BY: FITCH |LAST UPDATE DATE: 07/04/2000|
| HQ OPS OFFICER: CHAUNCEY GOULD +-----------------------------+
+------------------------------------------------+PERSON ORGANIZATION |
|EMERGENCY CLASS: N/A |STEVEN DENNIS R1 |
|10 CFR SECTION: | |
|AESF 50.72(b)(2)(ii) ESF ACTUATION | |
| | |
| | |
| | |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE |
+-----+----------+-------+--------+-----------------+--------+-----------------+
| | |
|2 N Y 100 Power Operation |100 Power Operation |
| | |
+------------------------------------------------------------------------------+
EVENT TEXT
+------------------------------------------------------------------------------+
| THE PLANT HAD ESF ACTUATIONS DUE TO LOSS OF THE "B" RPS BUS. |
| |
| "While operating at 100% power, Susquehanna Unit 2, experienced ESF |
| actuations for containment isolations as a result of an unexpected loss of |
| "B" RPS Bus caused by a trip of the RPS MG Set Output Breaker. All |
| containment isolations associated with a loss of "B" RPS Bus actuated and |
| went to completion. "B" RPS power was swapped to the alternate power supply |
| and affected systems restored to normal configuration." |
| |
| The actuations received were cooling water to recirc pump isolation, RWCU |
| isolation, containment sampling isolation, reactor building secondary |
| containment isolations and coolant sampling isolations. They also had |
| standby gas treatment initiation. The cause of the trip of the MG set is |
| being investigated. |
| |
| The NRC Resident Inspector was notified. |
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