Event Notification Report for September 27, 2000
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
09/26/2000 - 09/27/2000
Power Reactor
Event Number: 37385
Facility: DRESDEN
Region: 3 State: IL
Unit: [] [] [3]
RX Type: [1] GE-1,[2] GE-3,[3] GE-3
NRC Notified By: GRANT
HQ OPS Officer: JOHN MacKINNON
Region: 3 State: IL
Unit: [] [] [3]
RX Type: [1] GE-1,[2] GE-3,[3] GE-3
NRC Notified By: GRANT
HQ OPS Officer: JOHN MacKINNON
Notification Date: 09/27/2000
Notification Time: 21:04 [ET]
Event Date: 09/27/2000
Event Time: 18:45 [CDT]
Last Update Date: 09/27/2000
Notification Time: 21:04 [ET]
Event Date: 09/27/2000
Event Time: 18:45 [CDT]
Last Update Date: 09/27/2000
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(i) - DEG/UNANALYZED COND
10 CFR Section:
50.72(b)(2)(i) - DEG/UNANALYZED COND
Person (Organization):
BRENT CLAYTON (R3)
BRENT CLAYTON (R3)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 3 | N | N | 0 | Refueling | 0 | Refueling |
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.
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: 37384
Facility: NINE MILE POINT
Region: 1 State: NY
Unit: [1] [] []
RX Type: [1] GE-2,[2] GE-5
NRC Notified By: ERIC KELSEY
HQ OPS Officer: BOB STRANSKY
Region: 1 State: NY
Unit: [1] [] []
RX Type: [1] GE-2,[2] GE-5
NRC Notified By: ERIC KELSEY
HQ OPS Officer: BOB STRANSKY
Notification Date: 09/27/2000
Notification Time: 03:15 [ET]
Event Date: 09/27/2000
Event Time: 01:23 [EDT]
Last Update Date: 09/27/2000
Notification Time: 03:15 [ET]
Event Date: 09/27/2000
Event Time: 01:23 [EDT]
Last Update Date: 09/27/2000
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(ii) - RPS ACTUATION
10 CFR Section:
50.72(b)(2)(ii) - RPS ACTUATION
Person (Organization):
JOHN KINNEMAN (R1)
JOHN KINNEMAN (R1)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | A | N | 0 | Cold Shutdown | 0 | Cold Shutdown |
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.
"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.