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Event Notification Report for September 28, 2000

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           09/27/2000 - 09/28/2000

                              ** EVENT NUMBERS **

37384  37385  37386  

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   37384       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: NINE MILE POINT          REGION:  1  |NOTIFICATION DATE: 09/27/2000|
|    UNIT:  [1] [] []                 STATE:  NY |NOTIFICATION TIME: 03:15[EDT]|
|   RXTYPE: [1] GE-2,[2] GE-5                    |EVENT DATE:        09/27/2000|
+------------------------------------------------+EVENT TIME:        01:23[EDT]|
| NRC NOTIFIED BY:  ERIC KELSEY                  |LAST UPDATE DATE:  09/27/2000|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |JOHN KINNEMAN        R1      |
|10 CFR SECTION:                                 |                             |
|ARPS 50.72(b)(2)(ii)     RPS ACTUATION          |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     A          N       0        Cold Shutdown    |0        Cold Shutdown    |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| AUTOMATIC REACTOR SCRAM SIGNAL WITH ALL CONTROL RODS ALREADY INSERTED        |
|                                                                              |
| "While in Cold Shutdown conditions, Nine Mile Point Unit 1 experienced a     |
| Reactor Scram initiated by Low water level. All rods were fully inserted at  |
| the time of the initiation and all required safety functions operated as     |
| required. The cause of the low water level condition was due to a level      |
| transient experienced while placing the Reactor Water Cleanup System in      |
| service. The lowest indicated water level was 133 inches above top of active |
| fuel. Emergency Operating Procedures and Special Operating Procedures were   |
| implemented and reactor water level was returned to the normal cold shutdown |
| level of 149 inches above top of active fuel. There were no adverse effects  |
| on Reactor Plant Systems."                                                   |
|                                                                              |
| The NRC resident inspector will be informed of this event by the licensee.   |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   37385       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: DRESDEN                  REGION:  3  |NOTIFICATION DATE: 09/27/2000|
|    UNIT:  [] [] [3]                 STATE:  IL |NOTIFICATION TIME: 21:04[EDT]|
|   RXTYPE: [1] GE-1,[2] GE-3,[3] GE-3           |EVENT DATE:        09/27/2000|
+------------------------------------------------+EVENT TIME:        18:45[CDT]|
| NRC NOTIFIED BY:  GRANT                        |LAST UPDATE DATE:  09/27/2000|
|  HQ OPS OFFICER:  JOHN MacKINNON               +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |BRENT CLAYTON        R3      |
|10 CFR SECTION:                                 |                             |
|ADAS 50.72(b)(2)(i)      DEG/UNANALYZED COND    |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|                                                   |                          |
|3     N          N       0        Refueling        |0        Refueling        |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| INCORRECT TAP SETTING DISCOVERED                                             |
|                                                                              |
| During the Division II UV Test, it was discovered the tap setting on the     |
| overvoltage coil on the undervoltage relay (127-2-B-34) on Bus 34 was        |
| incorrectly set at 0.2 amps versus 2 amps.  The failure of this relay causes |
| a failure to re-energize Bus 34 from Bus 34-1 after a Loss of Off-Site Power |
| (LOOP) occurs requiring the Unit 3 Emergency Diesel Generator (EDG) to       |
| supply power to the bus.  The failure to re-energize Bus 34 prevents         |
| starting the 3C & 3D Containment Cooling Water Pumps.                        |
|                                                                              |
| Based on the events discovered during D3R16 Division II UV Test, it is       |
| suspected the ability of this relay to perform its design function has been  |
| lost since 02/12/99 during D3R15. Surveillance testing during the fuel cycle |
| would not have identified this deficiency due to paralleling the Unit 3 EDG  |
| with off-site power.  In this configuration the relay in question is not     |
| challenged.                                                                  |
|                                                                              |
| With the failure of this relay and a Design Basis Accident ,Loss Of Off-Site |
| Power with a Loss of Coolant Accident (LOOP/LOCA) and a single active        |
| failure of the 2/3 EDG (or Div I CCSW Loop Inoperable) a loss of containment |
| cooling function would occur.                                                |
|                                                                              |
| Work Package Instruction used on 02/12/99 to set the tap setting specified   |
| 0.2 amps instead of the correct value of 2 amps.  All other Unit 3 Buses     |
| have the correct tap setting for the overvoltage coil on the undervoltage    |
| relay.  Investigation into root cause is in progress.                        |
|                                                                              |
| The NRC  Resident Inspector was notified of this event by the licensee.      |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   37386       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: COOK                     REGION:  3  |NOTIFICATION DATE: 09/28/2000|
|    UNIT:  [1] [2] []                STATE:  MI |NOTIFICATION TIME: 01:23[EDT]|
|   RXTYPE: [1] W-4-LP,[2] W-4-LP                |EVENT DATE:        09/28/2000|
+------------------------------------------------+EVENT TIME:        01:21[EDT]|
| NRC NOTIFIED BY:  STEVE CHERBA                 |LAST UPDATE DATE:  09/28/2000|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |BRENT CLAYTON        R3      |
|10 CFR SECTION:                                 |                             |
|AARC 50.72(b)(1)(v)      OTHER ASMT/COMM INOP   |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          N       0        Refueling        |0        Refueling        |
|2     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| ELECTRICAL BUS OUTAGE WILL AFFECT TSC VENTILATION SYSTEM                     |
|                                                                              |
| "This event notification is for planned maintenance on Cook Unit 1's         |
| electrical buses that remove power from a portion of the TSC ventilation     |
| system. Contingencies are established to restore power to the TSC            |
| ventilation fan (if needed) to support Emergency Plan execution. The fan     |
| that will be unavailable boosts airflow through the TSC ventilation charcoal |
| clean-up filter subsystem. Ventilation flow will still pass through this     |
| filter without the booster fan, but TSC pressure will not be boosted to      |
| limit infiltration. Use of this fan is dependent on radiological conditions, |
| if radiological conditions warrant its use, and it is not available, the TSC |
| will relocate to the Unit 2 Control Room in accordance with plant            |
| procedures. Reporting this event is consistent with NUREG-1022, Rev 1        |
| criteria for reporting loss of ERFs.                                         |
|                                                                              |
| "No adverse consequences are expected from this outage. The TSC ventilation  |
| booster fan is expected to be unavailable for 48 hours, starting at 0121     |
| hours on 9-28-2000. Contingencies have been planned to restore power to the  |
| booster fan in 8 to 10 hours if needed. Follow-up notification will be made  |
| when the TSC is again fully available. The NRC Senior Site Resident          |
| Inspector has been informed of this planned evolution."                      |
+------------------------------------------------------------------------------+


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