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Home NRC Library Document Collections Events, Reports Associated with Event Notification Reports 2001

Event Notification Report for December 12, 2001

                         
                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           12/11/2001 - 12/12/2001

                              ** EVENT NUMBERS **

38557  
.
+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   38557       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: CATAWBA                  REGION:  2  |NOTIFICATION DATE: 12/11/2001|
|    UNIT:  [] [2] []                 STATE:  SC |NOTIFICATION TIME: 17:16[EST]|
|   RXTYPE: [1] W-4-LP,[2] W-4-LP                |EVENT DATE:        10/17/2001|
+------------------------------------------------+EVENT TIME:        10:39[EST]|
| NRC NOTIFIED BY:  ED BREWER                    |LAST UPDATE DATE:  12/11/2001|
|  HQ OPS OFFICER:  LEIGH TROCINE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |LEONARD WERT         R2      |
|10 CFR SECTION:                                 |                             |
|AINV 50.73(a)(1)         INVALID SPECIF SYSTEM A|                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE  
|
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|2     A          N       0        Cold Shutdown    |0        Cold Shutdown    |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| INVALID ACTUATION OF THE REACTOR PROTECTION SYSTEM WHILE THE UNIT WAS
IN     |
| COLD SHUTDOWN (60-Day Report)                                                |
|                                                                              |
| The following text is a portion of a facsimile received from the licensee:   |
|                                                                              |
| "This 60-day optional report, as allowed by 10CFR50.73(a)(1), is being made  |
| under the reporting requirement in 10CFR50.73(a)(2)(iv)(A) to describe an    |
| invalid actuation of a specified system, specifically the reactor protection |
| system (RPS).  On October 17, 2001, at 1039 with Unit 2 in MODE 5 with a     |
| boron concentration of 2531 ppm, an invalid reactor trip signal was          |
| generated from 2 out of 4 logic for overtemperature delta-T.  The reactor    |
| trip breakers opened as designed upon receipt of the invalid reactor trip    |
| signal.  All control rods and shutdown rods were already fully inserted      |
| before the invalid reactor trip signal trip signal was generated.  At the    |
| time of the invalid reactor trip signal, reactor protection channel III had  |
| been properly removed from service for maintenance testing.  Other           |
| maintenance technicians were in the process of setting up test equipment in  |
| reactor protection channel I for upcoming resistance temperature detector    |
| cross calibrations.  The technicians thought that the place where they were  |
| connecting the test equipment was isolated from the circuit and would have   |
| no effect on the plant.  During the connections, a momentary spike occurred  |
| on reactor protection channel I.  This completed the 2 out of 4 logic for an |
| overtemperature delta-T reactor trip, and a reactor trip occurred.  The      |
| control room operators entered appropriate procedures and verified proper    |
| equipment operation for the existing plant conditions. Both trains A [and] B |
| of the reactor protection system actuated.  This was a complete actuation,   |
| and the system performed as designed for the existing plant conditions.      |
| This event has been entered into the site-specific corrective action program |
| for resolution."                                                             |
|                                                                              |
| The licensee notified the NRC resident inspector and plans to notify         |
| applicable state, county, and local agencies.                                |
+------------------------------------------------------------------------------+
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