Event Notification Report for November 21, 2003
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
11/20/2003 - 11/21/2003
Power Reactor
Event Number: 40348
Facility: SUMMER
Region: 2 State: SC
Unit: [1] [] []
RX Type: [1] W-3-LP
NRC Notified By: PHIL ROSE
HQ OPS Officer: JOHN MacKINNON
Region: 2 State: SC
Unit: [1] [] []
RX Type: [1] W-3-LP
NRC Notified By: PHIL ROSE
HQ OPS Officer: JOHN MacKINNON
Notification Date: 11/21/2003
Notification Time: 15:46 [ET]
Event Date: 11/21/2003
Event Time: 09:10 [EST]
Last Update Date: 11/21/2003
Notification Time: 15:46 [ET]
Event Date: 11/21/2003
Event Time: 09:10 [EST]
Last Update Date: 11/21/2003
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
10 CFR Section:
50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Person (Organization):
DAVID AYRES (R2)
DAVID AYRES (R2)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | M/R | N | 0 | Hot Standby | 0 | Hot Standby |
CONTROL BANK "C" RODS TRIPPED DUE TO INCORRECT DIGITAL ROD POSITION INDICATION (DRPI)
"On Friday November 21, 2003, the V.C. Summer Nuclear Station was performing rod position testing in preparation for plant start-up, following refueling outage-14. The testing is in accordance with STP-106.002 Rod Position Indication Operational Test. Control Bank 'C' was being withdrawn. Per STP-106.002, RCS boron concentration was verified adequate to ensure Keff less than or equal to 0.95. When Control Bank 'C' reached 36 steps Digital Rod Position Indication system (DRPI) indication for rod M-4 went to 18 steps. At 0835, Control Rod motion was stopped and Abnormal Operating Procedure (AOP)-403.5, Stuck or Misaligned Control Rod, was entered after reviewing the AOP applicability versus current plant condition. At 0910 while taking action per the AOP, it was determined that both channels of DRPI were not functioning properly and per Tech Spec 3.10.5 the Rx Trip Breakers were immediately opened (manual actuation of the Reactor Protection System - reactor scram). Emergency Operating Procedure (EOP)-1.0, Reactor Trip, was entered. At 0915 EOP-1.0, was exited with the plant stable in Mode 3 (Hot Standby).
"At this time it appears there was failure in the DRPI system.
"This event is being reported in accordance with 10 CFR 50.72(b)(3)(IV)(A), a valid actuation of the Reactor Protection System (RPS)."
The NRC Resident Inspector was notified of this event by the licensee.
"On Friday November 21, 2003, the V.C. Summer Nuclear Station was performing rod position testing in preparation for plant start-up, following refueling outage-14. The testing is in accordance with STP-106.002 Rod Position Indication Operational Test. Control Bank 'C' was being withdrawn. Per STP-106.002, RCS boron concentration was verified adequate to ensure Keff less than or equal to 0.95. When Control Bank 'C' reached 36 steps Digital Rod Position Indication system (DRPI) indication for rod M-4 went to 18 steps. At 0835, Control Rod motion was stopped and Abnormal Operating Procedure (AOP)-403.5, Stuck or Misaligned Control Rod, was entered after reviewing the AOP applicability versus current plant condition. At 0910 while taking action per the AOP, it was determined that both channels of DRPI were not functioning properly and per Tech Spec 3.10.5 the Rx Trip Breakers were immediately opened (manual actuation of the Reactor Protection System - reactor scram). Emergency Operating Procedure (EOP)-1.0, Reactor Trip, was entered. At 0915 EOP-1.0, was exited with the plant stable in Mode 3 (Hot Standby).
"At this time it appears there was failure in the DRPI system.
"This event is being reported in accordance with 10 CFR 50.72(b)(3)(IV)(A), a valid actuation of the Reactor Protection System (RPS)."
The NRC Resident Inspector was notified of this event by the licensee.
Power Reactor
Event Number: 40349
Facility: PALO VERDE
Region: 4 State: AZ
Unit: [] [2] []
RX Type: [1] CE,[2] CE,[3] CE
NRC Notified By: JOHN GUNN
HQ OPS Officer: GERRY WAIG
Region: 4 State: AZ
Unit: [] [2] []
RX Type: [1] CE,[2] CE,[3] CE
NRC Notified By: JOHN GUNN
HQ OPS Officer: GERRY WAIG
Notification Date: 11/22/2003
Notification Time: 04:30 [ET]
Event Date: 11/21/2003
Event Time: 22:53 [MST]
Last Update Date: 11/22/2003
Notification Time: 04:30 [ET]
Event Date: 11/21/2003
Event Time: 22:53 [MST]
Last Update Date: 11/22/2003
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
10 CFR Section:
50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Person (Organization):
KRISS KENNEDY (R4)
KRISS KENNEDY (R4)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | N | N | 0 | Refueling | 0 | Refueling |
VALID ACTUATION OF THE "A" EMERGENCY DIESEL GENERATOR DURING TESTING
"The following event description is based on information currently available. If through subsequent reviews of this event, additional information is identified that is pertinent to this event or alters the information being provided at this time, a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73.
"On November 21, 2003, at approximately 22:53 Mountain Standard Time, Palo Verde Nuclear Generating Station Unit 2 experienced a valid actuation (start) of the 'A' Emergency Diesel Generator (EDG). Unit 2 had been performing testing of the capability to parallel the EDG 'A' with the Gas Turbine Generator #1 (alternate AC Power source for station blackout.) The Train 'A' 4.16 Kv bus had been successfully transferred to the EDG and loads carried by the EDG for approximately 5 minutes. When the EDG speed control was taken from 'droop' mode (load sharing) to 'isochronous' mode (fixed frequency,) the EDG output breaker tripped opened, resulting in a valid Loss of Power (LOP) signal based on undervoltage on the Train 'A' bus. The EDG resupplied the bus in the LOP mode.
"Offsite power remained available to both safety buses throughout the event. The other (Train 'B') safety bus is being supplied by offsite power and its EDG is operable. The offsite electrical grid is stable.
"Palo Verde Unit 2 is shutdown and defueled in its 11th refueling outage. No other ESF actuations occurred and none were required. There were no structures, systems, or components that were inoperable at the time of discovery that contributed to this condition. There were no failures that rendered a train of a safety system inoperable and no failures of components with multiple functions were involved. The event did not result in the release of radioactivity to the environment and did not adversely affect the safe operation of the plant or health and safety of the public.
"Troubleshooting will be conducted to determine the cause of the EDG output breaker opening."
The licensee has notified the NRC Resident Inspector.
"The following event description is based on information currently available. If through subsequent reviews of this event, additional information is identified that is pertinent to this event or alters the information being provided at this time, a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73.
"On November 21, 2003, at approximately 22:53 Mountain Standard Time, Palo Verde Nuclear Generating Station Unit 2 experienced a valid actuation (start) of the 'A' Emergency Diesel Generator (EDG). Unit 2 had been performing testing of the capability to parallel the EDG 'A' with the Gas Turbine Generator #1 (alternate AC Power source for station blackout.) The Train 'A' 4.16 Kv bus had been successfully transferred to the EDG and loads carried by the EDG for approximately 5 minutes. When the EDG speed control was taken from 'droop' mode (load sharing) to 'isochronous' mode (fixed frequency,) the EDG output breaker tripped opened, resulting in a valid Loss of Power (LOP) signal based on undervoltage on the Train 'A' bus. The EDG resupplied the bus in the LOP mode.
"Offsite power remained available to both safety buses throughout the event. The other (Train 'B') safety bus is being supplied by offsite power and its EDG is operable. The offsite electrical grid is stable.
"Palo Verde Unit 2 is shutdown and defueled in its 11th refueling outage. No other ESF actuations occurred and none were required. There were no structures, systems, or components that were inoperable at the time of discovery that contributed to this condition. There were no failures that rendered a train of a safety system inoperable and no failures of components with multiple functions were involved. The event did not result in the release of radioactivity to the environment and did not adversely affect the safe operation of the plant or health and safety of the public.
"Troubleshooting will be conducted to determine the cause of the EDG output breaker opening."
The licensee has notified the NRC Resident Inspector.