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Event Notification Report for December 28, 2001

                         
                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           12/27/2001 - 12/28/2001

                              ** EVENT NUMBERS **

38592  38597  38598  
.
+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   38592       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: HATCH                    REGION:  2  |NOTIFICATION DATE: 12/25/2001|
|    UNIT:  [] [2] []                 STATE:  GA |NOTIFICATION TIME: 20:40[EST]|
|   RXTYPE: [1] GE-4,[2] GE-4                    |EVENT DATE:        12/25/2001|
+------------------------------------------------+EVENT TIME:        18:19[EST]|
| NRC NOTIFIED BY:  STEVE HOWARD                 |LAST UPDATE DATE:  12/27/2001|
|  HQ OPS OFFICER:  JOHN MacKINNON               +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |LEONARD WERT         R2      |
|10 CFR SECTION:                                 |JOSEPH HOLONICH      IRO     |
|ARPS 50.72(b)(2)(iv)(B)  RPS ACTUATION - CRITICA|                             |
|AESF 50.72(b)(3)(iv)(A)  VALID SPECIF SYS ACTUAT|                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE  
|
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|2     A/R        Y       100      Power Operation  |0        Hot Shutdown     |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| AUTOMATIC REACTOR SCRAM DUE TO 'A' RECIRCULATION PUMP SPEED
UNEXPECTEDLY     |
| INCREASING                                                                   |
|                                                                              |
| "At 18:19 Eastern on 12/25/01, Hatch Nuclear Plant Unit 2 reactor tripped.   |
| The cause is presently under investigation.  Preliminary indications are     |
| that the 'A' Recirculation Pump speed increased.  Reactor power increased    |
| causing the all four channels in the Neutron Monitoring System to trip.      |
| Group 2 Primary Containment isolation occurred.  All group 2 isolated as     |
| expected.  No other group isolations were required.  RFPTs were used to      |
| maintain reactor water level, and Main Turbine Bypass valves maintained      |
| reactor pressure.  No initiation signals required ECCS or RCIC to            |
| initiate."                                                                   |
|                                                                              |
| On the automatic reactor scram, one control rod inserted to the 01 position  |
| and drifted to the 00 position.  The swing Emergency Diesel Generator, 1B,   |
| is degraded but fully operable.  The only other problem was that the Main    |
| Generator Output breakers did not automatically open but were manually       |
| opened from the control room.  This problem has occurred before, and the     |
| control room operators are watching the output breakers.                     |
|                                                                              |
| The NRC resident inspector was notified of this event by the licensee.       |
|                                                                              |
| ***** UPDATE FROM GUY S. GRIFFIS TO LEIGH TROCINE AT 1217 ON 12/27/01 *****  |
|                                                                              |
| This update was made to correct/clarify the cause of the automatic reactor   |
| scram from 100% power and to provide additional information.                 |
|                                                                              |
| It was initially reported that 'A' recirculation pump speed increased and    |
| caused all four channels in the neutron monitoring system to trip.  However, |
| further review determined that decreased main steam line 'B' flow caused the |
| neutron monitoring system trip due to increased flux.  Initial diagnostics   |
| indicate the 2B21-F028B main steam isolation valve as the failure.           |
|                                                                              |
| The licensee's investigation is still ongoing.  The licensee plans to        |
| provide additional detailed information in a Licensee Event Report.          |
|                                                                              |
| NOTE:  Cold Shutdown was achieved at 0255 on 12/27/01 in compliance with     |
| Technical Specification 3.6.1.3.e.                                           |
|                                                                              |
| The licensee notified the NRC resident inspector.  The NRC operations        |
| officer notified the R2DO (Boland) and IRO (Holonich).                       |
+------------------------------------------------------------------------------+
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+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   38597       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: FITZPATRICK              REGION:  1  |NOTIFICATION DATE: 12/27/2001|
|    UNIT:  [1] [] []                 STATE:  NY |NOTIFICATION TIME: 14:10[EST]|
|   RXTYPE: [1] GE-4                             |EVENT DATE:        12/16/2001|
+------------------------------------------------+EVENT TIME:        00:18[EST]|
| NRC NOTIFIED BY:  ANDY HALLIDAY                |LAST UPDATE DATE:  12/27/2001|
|  HQ OPS OFFICER:  LEIGH TROCINE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |MICHELE EVANS        R1      |
|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  
|
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| INVALID PRIMARY AND SECONDARY CONTAINMENT ISOLATION DUE TO A SPURIOUS   
    |
| UPSCALE SPIKE OF REACTOR BUILDING VENTILATION RADIATION MONITOR B 
(60-Day   |
| Report)                                                                      |
|                                                                              |
| The following text is a portion of a facsimile received from the licensee:   |
|                                                                              |
| "Event Description"                                                          |
|                                                                              |
| "At 0018 hours on December 16, 2001, with the plant operating at 100 percent |
| of rated thermal power, Reactor Building (Secondary Containment) Ventilation |
| Exhaust Radiation Monitor B spiked upscale and immediately returned to       |
| normal."                                                                     |
|                                                                              |
| "The radiation monitor upscale spike (trip) resulted in automatic closure of |
| outboard isolation valves and therefore isolation of the following systems   |
| or functions:                                                                |
| *  Primary Containment Drywell and Suppression Chamber pressure sensing for  |
| alarm and indication functions only,                                         |
| *  Primary Containment Continuous Atmosphere Monitoring (CAM) for            |
| particulate and gaseous radioactivity monitoring, and                        |
| *  Primary Containment Hydrogen and Oxygen Analyzer B."                      |
|                                                                              |
| "The trip signal also resulted in automatic isolation of the Reactor         |
| Building (Secondary Containment) Ventilation system and starting of Standby  |
| Gas Treatment subsystem B to maintain the reactor building atmosphere at a   |
| slightly negative pressure."                                                 |
|                                                                              |
| "System performance was in accordance with the design.  Examination of       |
| operating records indicated that the redundant radiation monitor, other      |
| monitoring systems, and the plant computer system did not detect any         |
| abnormal radioactivity.  Shift operating and radiation protection personnel  |
| investigated and did not detect any abnormal radiological conditions.        |
| Examination of the radiation monitor did not reveal any indication of        |
| abnormal operation, and it was concluded that the trip signal had been a     |
| spurious invalid signal."                                                    |
|                                                                              |
| "Shift operating personnel completed restoration of the affected systems to  |
| normal at 0104 hours, 46 minutes after the event start."                     |
|                                                                              |
| "Actions Taken"                                                              |
|                                                                              |
| "1.  Verified system response was in accordance with the design.             |
| 2.  Investigated radiological conditions and determined they were normal.    |
| 3.  Restored the affected systems to normal."                                |
|                                                                              |
| The licensee notified the NRC resident inspector.                            |
+------------------------------------------------------------------------------+
.
+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   38598       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: PILGRIM                  REGION:  1  |NOTIFICATION DATE: 12/27/2001|
|    UNIT:  [1] [] []                 STATE:  MA |NOTIFICATION TIME: 16:03[EST]|
|   RXTYPE: [1] GE-3                             |EVENT DATE:        12/27/2001|
+------------------------------------------------+EVENT TIME:        13:21[EST]|
| NRC NOTIFIED BY:  DOUG PERRY                   |LAST UPDATE DATE:  12/27/2001|
|  HQ OPS OFFICER:  LEIGH TROCINE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |MICHELE EVANS        R1      |
|10 CFR SECTION:                                 |                             |
|ARPS 50.72(b)(2)(iv)(B)  RPS ACTUATION - CRITICA|                             |
|AESF 50.72(b)(3)(iv)(A)  VALID SPECIF SYS ACTUAT|                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE  
|
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     M/R        Y       100      Power Operation  |0        Hot Shutdown     |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| MANUAL REACTOR SCRAM AFTER TWO RECIRCULATION MOTOR-GENERATOR (MG)
SETS       |
| TRIPPED DURING THE PERFORMANCE OF ANTICIPATED TRANSIENT WITHOUT
SCRAM (ATWS) |
| LOGIC TESTING                                                                |
|                                                                              |
| The following text is a portion of a facsimile received from the licensee:   |
|                                                                              |
| "While performing ATWS logic testing, both [the] 'A' [and] 'B'               |
| [recirculation] MG sets tripped, and the reactor was scrammed.  The cause of |
| the scram is being determined at this time.  All control rods fully inserted |
| on the scram.  All safety systems functioned properly during the transient.  |
| The plant is in the process of being maneuvered to Cold Shutdown."           |
|                                                                              |
| The licensee stated that the main steam isolation valves remained open and   |
| that none of the safety relief valves lifted.  In addition, there were no    |
| emergency core cooling system actuations, and none were required.  The       |
| reported engineered safety feature actuation was the manual actuation of the |
| reactor protection system.                                                   |
|                                                                              |
| The unit is currently stable in Hot Shutdown.  Normal condensate and         |
| feedwater is being utilized to supply water to the reactor vessel, and the   |
| condenser is being utilized as a heat sink.  Containment parameters are      |
| normal, offsite power is available, and the electrical grid is stable.  The  |
| emergency diesel generators and engineered safety feature systems are        |
| available if needed.                                                         |
|                                                                              |
| The licensee stated that the ATWS logic test procedure was not new and that  |
| it had been performed on several occasions in the past.  The ATWS logic test |
| was successfully completed for the 'A' side earlier today, and the plant     |
| transient occurred during the performance of the ATWS logic test for the 'B' |
| side.  The cause of the recirculation MG set trips is currently under        |
| investigation.                                                               |
|                                                                              |
| The licensee notified the NRC resident inspector.                            |
+------------------------------------------------------------------------------+
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