Event Notification Report for January 11, 2008
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
01/10/2008 - 01/11/2008
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
Power Reactor
Event Number: 43894
Facility: WATTS BAR
Region: 2 State: TN
Unit: [1] [] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: GREG EVANS
HQ OPS Officer: PETE SNYDER
Region: 2 State: TN
Unit: [1] [] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: GREG EVANS
HQ OPS Officer: PETE SNYDER
Notification Date: 01/11/2008
Notification Time: 15:46 [ET]
Event Date: 01/11/2008
Event Time: 15:10 [EST]
Last Update Date: 02/08/2008
Notification Time: 15:46 [ET]
Event Date: 01/11/2008
Event Time: 15:10 [EST]
Last Update Date: 02/08/2008
Emergency Class: UNUSUAL EVENT
10 CFR Section:
76.120(a)(4) - EMERGENCY DECLARED
10 CFR Section:
76.120(a)(4) - EMERGENCY DECLARED
Person (Organization):
MALCOLM WIDMANN (R2)
MARY JANE ROSS-LEE (NRR)
JEFFREY CRUZ (IRD)
MALCOLM WIDMANN (R2)
MARY JANE ROSS-LEE (NRR)
JEFFREY CRUZ (IRD)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | Y | 100 | Power Operation | 100 | Power Operation |
DISCOVERY OF AN AFTER THE FACT UNUSUAL EVENT
At 1510, "[Watts Bar Nuclear (WBN)] had identified RCS leakage in excess of 25 gallons per minute (gpm). The leakage was estimated at 105 gpm. This is a report notification only and not a declaration. The EAL that was exceeded was 2.6, RCS identified leakage. While placing a mixed bed demineralizer in service VCT level was observed to have dropped 10%. The demineralizer was immediately removed from service. This terminated the drop in VCT level. In accordance with WBN EPIP-1 Emergency Classification Flowchart, section 3.0 step 3.3.7, if an EAL was exceeded but the emergency has been totally resolved (prior to declaration), the emergency condition that was appropriate shall not be declared but reported only. The duration of the leakage was approximately 15 minutes. The unit remains at mode 1 and 100% power. The cause for the unexpected level decrease is under investigation at this time. There were no radiological releases associated."
The licensee will notify the NRC Resident Inspector.
* * * UPDATE FROM MICHAEL BRANDON TO JOE O'HARA AT 1327 ON 1/15/08 * * *
The original report contains a typographical error. The leak duration was reported as 15 minutes. The correct time period is 1.5 minutes.
Notified R2DO(Moorman)
* * * RETRACTION ON 2/8/2008 AT 1710 FROM MICHAEL BRANDON TO MARK ABRAMOVITZ * * *
"On January 11, 2008, TVA notified the NRC of the discovery of an after the fact unusual event. The reported event described potential RCS leakage in excess of 25 GPM that was approximately 1 and 1/2 minutes in duration. The estimated magnitude of this leak was based on a step change in Volume Control Tank (VCT) level that occurred when placing the 1A Mixed Bed Demineralizer in service. TVA's post-event investigation concluded the cause of the VCT level change was the filling of a void in the 1A Mixed Bed Demineralizer. The cause of the void was a procedural deficiency in the flush methodology used when returning the demineralizer to service. Based on the evaluation of this event, TVA has concluded that no actual RCS leakage occurred. The RCS pressure boundary remained intact throughout this evolution.
"Based on the result of this evaluation and the subsequent successful alignment of the demineralizer without incident, TVA is retracting this event.
"The licensee has notified the NRC Resident of this retraction."
Notified the R2DO (Munday) and NRR EO (Brown).
At 1510, "[Watts Bar Nuclear (WBN)] had identified RCS leakage in excess of 25 gallons per minute (gpm). The leakage was estimated at 105 gpm. This is a report notification only and not a declaration. The EAL that was exceeded was 2.6, RCS identified leakage. While placing a mixed bed demineralizer in service VCT level was observed to have dropped 10%. The demineralizer was immediately removed from service. This terminated the drop in VCT level. In accordance with WBN EPIP-1 Emergency Classification Flowchart, section 3.0 step 3.3.7, if an EAL was exceeded but the emergency has been totally resolved (prior to declaration), the emergency condition that was appropriate shall not be declared but reported only. The duration of the leakage was approximately 15 minutes. The unit remains at mode 1 and 100% power. The cause for the unexpected level decrease is under investigation at this time. There were no radiological releases associated."
The licensee will notify the NRC Resident Inspector.
* * * UPDATE FROM MICHAEL BRANDON TO JOE O'HARA AT 1327 ON 1/15/08 * * *
The original report contains a typographical error. The leak duration was reported as 15 minutes. The correct time period is 1.5 minutes.
Notified R2DO(Moorman)
* * * RETRACTION ON 2/8/2008 AT 1710 FROM MICHAEL BRANDON TO MARK ABRAMOVITZ * * *
"On January 11, 2008, TVA notified the NRC of the discovery of an after the fact unusual event. The reported event described potential RCS leakage in excess of 25 GPM that was approximately 1 and 1/2 minutes in duration. The estimated magnitude of this leak was based on a step change in Volume Control Tank (VCT) level that occurred when placing the 1A Mixed Bed Demineralizer in service. TVA's post-event investigation concluded the cause of the VCT level change was the filling of a void in the 1A Mixed Bed Demineralizer. The cause of the void was a procedural deficiency in the flush methodology used when returning the demineralizer to service. Based on the evaluation of this event, TVA has concluded that no actual RCS leakage occurred. The RCS pressure boundary remained intact throughout this evolution.
"Based on the result of this evaluation and the subsequent successful alignment of the demineralizer without incident, TVA is retracting this event.
"The licensee has notified the NRC Resident of this retraction."
Notified the R2DO (Munday) and NRR EO (Brown).
Power Reactor
Event Number: 43895
Facility: WOLF CREEK
Region: 4 State: KS
Unit: [1] [] []
RX Type: [1] W-4-LP
NRC Notified By: JEFF ISCH
HQ OPS Officer: JOE O'HARA
Region: 4 State: KS
Unit: [1] [] []
RX Type: [1] W-4-LP
NRC Notified By: JEFF ISCH
HQ OPS Officer: JOE O'HARA
Notification Date: 01/11/2008
Notification Time: 17:53 [ET]
Event Date: 01/11/2008
Event Time: 16:22 [CST]
Last Update Date: 01/14/2008
Notification Time: 17:53 [ET]
Event Date: 01/11/2008
Event Time: 16:22 [CST]
Last Update Date: 01/14/2008
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(i) - PLANT S/D REQD BY TS
10 CFR Section:
50.72(b)(2)(i) - PLANT S/D REQD BY TS
Person (Organization):
RUSSELL BYWATER (R4)
RUSSELL BYWATER (R4)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | Y | 100 | Power Operation | 97 | Power Operation |
TECH. SPEC. REQUIRED SHUTDOWN DUE TO GAS VOIDING IN DISCHARGE PIPING
"Gas intrusion into ECCS piping required entry into Technical Specification (TS) 3.0.3.
"Wolf Creek was operating at 100% power when gas voiding was discovered in RHR discharge piping common to both trains of ECCS. Due to void reoccurring in excess of predetermined limits both trains of ECCS were declared inoperable at 1525 CST. A TS required shutdown was commenced at 1622.
"Engineering is researching the composition of the gas and possible sources."
The licensee must determine that the line is solid with fluid without any gas voiding before exiting the TS required shutdown. All normal and emergency power supplies are available. All EDG's are operable. Reactor power is being reduced one-half a percent per minute.
The licensee notified the NRC Resident Inspector.
* * * UPDATE PROVIDED BY DIANE HOOPER TO JEFF ROTTON AT 1932 ON 01/14/08 * * *
"At 1550 [CST] on 1/14/2008, Engineering notified control room that the A RHR pump suction from the recirc sump has a void in excess of the allowable limit. Due to the isolation of the 'piggyback' line from the A RHR to the suction of the CCPs, [Wolf Creek] no longer has 'at least the ECCS flow equivalent to a single OPERABLE ECCS train available.' [Wolf Creek] has already entered condition B of 3.5.2 and the cooldown requirement from action B of 3.5.2 is more restrictive than the cooldown requirement of 3.0.3. No additional actions need to be taken to comply with Tech Specs.
"At 1700 [CST] on 1/14, Engineering reports that the voids in the 'piggyback' line has been filled to within acceptable limits."
The licensee will notify the NRC Resident Inspector. Notified the R4DO (Spitzberg)
"Gas intrusion into ECCS piping required entry into Technical Specification (TS) 3.0.3.
"Wolf Creek was operating at 100% power when gas voiding was discovered in RHR discharge piping common to both trains of ECCS. Due to void reoccurring in excess of predetermined limits both trains of ECCS were declared inoperable at 1525 CST. A TS required shutdown was commenced at 1622.
"Engineering is researching the composition of the gas and possible sources."
The licensee must determine that the line is solid with fluid without any gas voiding before exiting the TS required shutdown. All normal and emergency power supplies are available. All EDG's are operable. Reactor power is being reduced one-half a percent per minute.
The licensee notified the NRC Resident Inspector.
* * * UPDATE PROVIDED BY DIANE HOOPER TO JEFF ROTTON AT 1932 ON 01/14/08 * * *
"At 1550 [CST] on 1/14/2008, Engineering notified control room that the A RHR pump suction from the recirc sump has a void in excess of the allowable limit. Due to the isolation of the 'piggyback' line from the A RHR to the suction of the CCPs, [Wolf Creek] no longer has 'at least the ECCS flow equivalent to a single OPERABLE ECCS train available.' [Wolf Creek] has already entered condition B of 3.5.2 and the cooldown requirement from action B of 3.5.2 is more restrictive than the cooldown requirement of 3.0.3. No additional actions need to be taken to comply with Tech Specs.
"At 1700 [CST] on 1/14, Engineering reports that the voids in the 'piggyback' line has been filled to within acceptable limits."
The licensee will notify the NRC Resident Inspector. Notified the R4DO (Spitzberg)