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Event Notification Report for September 29, 2000

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           09/28/2000 - 09/29/2000

                              ** EVENT NUMBERS **

37386  37387  37388  

+------------------------------------------------------------------------------+
|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."                      |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   37387       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: MILLSTONE                REGION:  1  |NOTIFICATION DATE: 09/28/2000|
|    UNIT:  [] [] [3]                 STATE:  CT |NOTIFICATION TIME: 18:43[EDT]|
|   RXTYPE: [1] GE-3,[2] CE,[3] W-4-LP           |EVENT DATE:        09/28/2000|
+------------------------------------------------+EVENT TIME:        18:35[EDT]|
| NRC NOTIFIED BY:  ROBERT SMITH                 |LAST UPDATE DATE:  09/28/2000|
|  HQ OPS OFFICER:  DOUG WEAVER                  +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |FRANK COSTELLO       R1      |
|10 CFR SECTION:                                 |                             |
|AOUT 50.72(b)(1)(ii)(B)  OUTSIDE DESIGN BASIS   |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|                                                   |                          |
|3     N          Y       100      Power Operation  |100      Power Operation  |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| OUTSIDE DESIGN BASIS  -  PUMP POWER SUPPLY DOES NOT MEET SAFE SHUTDOWN       |
| REQUIREMENTS                                                                 |
|                                                                              |
| On September 28, 2000 at approximately 1835, it was determined that the      |
| power cable routing for the 'B' charging pump is not in accordance with the  |
| assumptions in the Millstone Unit 3 Fire Safe Shutdown Analysis. This        |
| condition could have resulted in the inability to maintain RCP seal cooling  |
| in the event of a design basis fire.   This condition is historical in       |
| nature.   In accordance with the Millstone Unit 3 Technical Requirements     |
| Manual, a fire watch has been established in the affected area as a          |
| compensatory measure until a corrective action plan can be developed and     |
| implemented.   All other fire protection features in the affected areas are  |
| operable.                                                                    |
|                                                                              |
| The cable is supposed to be run inside of a fire curtain, but instead was    |
| run outside of this curtain.                                                 |
|                                                                              |
| The licensee notified the NRC resident inspector.                            |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   37388       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: PEACH BOTTOM             REGION:  1  |NOTIFICATION DATE: 09/28/2000|
|    UNIT:  [2] [3] []                STATE:  PA |NOTIFICATION TIME: 19:26[EDT]|
|   RXTYPE: [2] GE-4,[3] GE-4                    |EVENT DATE:        09/28/2000|
+------------------------------------------------+EVENT TIME:        17:30[EDT]|
| NRC NOTIFIED BY:  JAMES KOVALCHICK             |LAST UPDATE DATE:  09/28/2000|
|  HQ OPS OFFICER:  DOUG WEAVER                  +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |FRANK COSTELLO       R1      |
|10 CFR SECTION:                                 |                             |
|AINB 50.72(b)(2)(iii)(B) POT RHR INOP           |                             |
|AIND 50.72(b)(2)(iii)(D) ACCIDENT MITIGATION    |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|2     N          N       0        Refueling        |0        Refueling        |
|3     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| POTENTIAL LOSS OF RHR AND ACCIDENT MITIGATION CAPABILITY                     |
|                                                                              |
| ON 09/28/00 AT 04:30 HRS. SURVEILLANCE TESTING SHOWED THAT A CHECK VALVE     |
| FAILED TO ISOLATE FLOW BETWEEN THE EMERGENCY SERVICE WATER (ESW) SYSTEM AND  |
| THE NON-SAFETY                                                               |
| RELATED UNIT 2 SERVICE WATER (SW) SYSTEM.  FAILURE TO PREVENT FLOW FROM THE  |
| EMERGENCY SERVICE WATER SYSTEM TO THE SERVICE WATER SYSTEM COULD RENDER BOTH |
| ESW SUBSYSTEMS INOPERABLE.                                                   |
|                                                                              |
| AT 05:58 ON 09/28/00, A MANUALLY OPERATED BLOCK VALVE WAS CLOSED BETWEEN THE |
| SYSTEMS TO MAINTAIN INTEGRITY OF THE ESW SUBSYSTEMS.  THIS ACTION ENSURES    |
| THAT BOTH ESW                                                                |
| SUBSYSTEMS ARE MAINTAINED OPERABLE.                                          |
|                                                                              |
| FURTHER EVALUATION AND TESTING WAS PERFORMED AND AT 17:30 HRS. ON 09/28/00,  |
| THE CONCLUSION WAS REACHED THAT THIS CONDITION COULD ALONE HAVE PREVENTED    |
| THE FULFILLMENT OF THE ESW SYSTEM SAFETY FUNCTION.                           |
|                                                                              |
| The licensee notified the NRC resident inspector.                            |
+------------------------------------------------------------------------------+


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