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Event Notification Report for January 25, 2002

                         
                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           01/24/2002 - 01/25/2002

                              ** EVENT NUMBERS **

38648  

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|Power Reactor                                    |Event Number:   38648       |
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| FACILITY: SUSQUEHANNA              REGION:  1  |NOTIFICATION DATE: 01/24/2002|
|    UNIT:  [1] [2] []                STATE:  PA |NOTIFICATION TIME: 18:20[EST]|
|   RXTYPE: [1] GE-4,[2] GE-4                    |EVENT DATE:        01/24/2002|
+------------------------------------------------+EVENT TIME:        11:00[EST]|
| NRC NOTIFIED BY:  GORDON ROBINSON              |LAST UPDATE DATE:  01/24/2002|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |PETE ESELGROTH       R1      |
|10 CFR SECTION:                                 |                             |
|AINA 50.72(b)(3)(v)(A)   POT UNABLE TO SAFE SD  |                             |
|AINB 50.72(b)(3)(v)(B)   POT RHR INOP           |                             |
|AIND 50.72(b)(3)(v)(D)   ACCIDENT MITIGATION    |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE  
|
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          Y       93       Power Operation  |93       Power Operation  |
|2     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| FAILURE OF REACTOR VESSEL WATER LEVEL SWITCH                                 |
|                                                                              |
| "At 11:00 EST, during performance of the 24 Month Calibration of Reactor     |
| Vessel Water Level Channels on Unit 2, Level Indicating Switch               |
| LIS-B21-2N031C would not properly relock following calibration. As a result  |
| of this, the switch was declared inoperable. A review of the design drawings |
| revealed that this switch provides inputs (through relays) that affect the   |
| reset logic for the 'A' and 'C' ESW pumps and the trips for the 'A' Reactor  |
| and Turbine Building Chillers on a Low Reactor Water Level signal. Without   |
| this switch functioning properly, the listed ESW pump start timers would not |
| reset as required and the listed chillers would not trip as required on the  |
| Low Reactor Water signal. The Tech Spec Basis for this instrumentation       |
| indicates that without these features, both offsite circuits and the         |
| associated Diesel Generators would be inoperable. Given this, both offsite   |
| sources and two (2) Diesel Generators were declared inoperable. SSES safety  |
| analysis requires three Operable Diesel Generators to safely shutdown the    |
| plant. Given this, this condition requires an 8 hour ENS notification in     |
| accordance with 10CFR50.72(b)(3)(v).                                         |
|                                                                              |
| "As a result of this condition, LCO 3.0.3 was entered on both Unit 1 and     |
| Unit 2 (in addition to other applicable LCO's). As of 13:00 on 01/24/02, the |
| switch was repaired and declared operable (and the associated LCO's were     |
| cleared).                                                                    |
|                                                                              |
| "There were no Diesel Generators, ECCS, or Tech Spec Electrical Distribution |
| systems out of service at the time of the event."                            |
|                                                                              |
| The NRC resident inspector has been informed of this notification by the     |
| licensee.                                                                    |
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