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 +------------------------------------------------------------------------------+ |Power Reactor |Event Number: 38648 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | 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 | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | 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. | +------------------------------------------------------------------------------+
Page Last Reviewed/Updated Thursday, March 25, 2021
Page Last Reviewed/Updated Thursday, March 25, 2021