Event Notification Report for September 07, 2009
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
09/06/2009 - 09/07/2009
EVENT NUMBERS
45331
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
Power Reactor
Event Number: 45331
Facility: WATTS BAR
Region: 2 State: TN
Unit: [1] [] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: NEWTON LACY
HQ OPS Officer: STEVE SANDIN
Region: 2 State: TN
Unit: [1] [] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: NEWTON LACY
HQ OPS Officer: STEVE SANDIN
Notification Date: 09/07/2009
Notification Time: 22:02 [ET]
Event Date: 09/07/2009
Event Time: 21:20 [EDT]
Last Update Date: 09/15/2009
Notification Time: 22:02 [ET]
Event Date: 09/07/2009
Event Time: 21:20 [EDT]
Last Update Date: 09/15/2009
Emergency Class: NON EMERGENCY
10 CFR Section:
10 CFR Section:
Person (Organization):
DANIEL RICH (R2DO)
JOSEPH GIITTER (NRR)
WILLIAM GOTT (IRD)
DANIEL RICH (R2DO)
JOSEPH GIITTER (NRR)
WILLIAM GOTT (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 AFTER-THE-FACT EMERGENCY CONDITION UNUSUAL EVENT
"This report documents a condition in which WBN [Watts Bar Nuclear] Unit 1 met the criteria to declare a NOUE [Notification of Unusual Event] based on RCS [Reactor Coolant System] unidentified leakage. Prior to declaration, the event was terminated thus no declaration was made. This event is reportable within one hour as an acceptable alternative to reporting in accordance with 10CFR50.72(a)(1)(i) - declaration of any of the emergency classes specified in the licensees approved emergency plan.
"During tagout installation in support of planned maintenance on the cation bed flush valve (1-FLV-62-921) in the CVCS/Letdown system, isolation boundary valve leakage of approximately 80 gpm was present for approximately three minutes. The leakage was terminated by reclosing opened vent (1-VTV-62-917) and drain valves (1-DRV-62-920). Cation Bed Inlet (l-ISV-62-915) and Outlet (1-ISV-62-916) and all other boundary valve isolations were verified to be in the correct, closed position per the tagout instructions. This RCS leakage was directed to the Tritiated Drain Collector Tank, thus all leakage was contained within plant systems and no radiological releases resulted. A work order will be initiated to troubleshoot and repair the faulty isolation valve.
"This amount of leakage is in excess of the amount specified in WBN Emergency Plans for declaration of an NOUE based on >10 gpm unidentified leakage per EAL 2.5. Prior to declaration, the event was terminated, thus no declaration was made."
The State of Tennessee and the NRC Resident Inspector has been notified.
* * * RETRACTION ON 9/15/2009 AT 1113 FROM WES DANIEL TO MARK ABRAMOVITZ * * *
"Event Notice 45331 reported a condition in which WBN Unit 1 conservatively determined it met the criteria to declare a NOUE based on RCS unidentified leakage. Prior to declaration, the event was terminated thus no declaration was made.
"Based upon further review and discussion with others in the industry, the NOUE criterion cited, EAL 2.5, applies to specific sources of excessive RCS leakage. The source of the leakage discussed in the event has been confirmed as CVCS leakage, not RCS leakage. An action to clarify the basis and scope of this EAL is being pursued within TVA's Corrective Action Program. Therefore, Event Notice 45331 is being retracted.
"The NRC resident has been notified."
Notified the R2DO (Blamey).
"This report documents a condition in which WBN [Watts Bar Nuclear] Unit 1 met the criteria to declare a NOUE [Notification of Unusual Event] based on RCS [Reactor Coolant System] unidentified leakage. Prior to declaration, the event was terminated thus no declaration was made. This event is reportable within one hour as an acceptable alternative to reporting in accordance with 10CFR50.72(a)(1)(i) - declaration of any of the emergency classes specified in the licensees approved emergency plan.
"During tagout installation in support of planned maintenance on the cation bed flush valve (1-FLV-62-921) in the CVCS/Letdown system, isolation boundary valve leakage of approximately 80 gpm was present for approximately three minutes. The leakage was terminated by reclosing opened vent (1-VTV-62-917) and drain valves (1-DRV-62-920). Cation Bed Inlet (l-ISV-62-915) and Outlet (1-ISV-62-916) and all other boundary valve isolations were verified to be in the correct, closed position per the tagout instructions. This RCS leakage was directed to the Tritiated Drain Collector Tank, thus all leakage was contained within plant systems and no radiological releases resulted. A work order will be initiated to troubleshoot and repair the faulty isolation valve.
"This amount of leakage is in excess of the amount specified in WBN Emergency Plans for declaration of an NOUE based on >10 gpm unidentified leakage per EAL 2.5. Prior to declaration, the event was terminated, thus no declaration was made."
The State of Tennessee and the NRC Resident Inspector has been notified.
* * * RETRACTION ON 9/15/2009 AT 1113 FROM WES DANIEL TO MARK ABRAMOVITZ * * *
"Event Notice 45331 reported a condition in which WBN Unit 1 conservatively determined it met the criteria to declare a NOUE based on RCS unidentified leakage. Prior to declaration, the event was terminated thus no declaration was made.
"Based upon further review and discussion with others in the industry, the NOUE criterion cited, EAL 2.5, applies to specific sources of excessive RCS leakage. The source of the leakage discussed in the event has been confirmed as CVCS leakage, not RCS leakage. An action to clarify the basis and scope of this EAL is being pursued within TVA's Corrective Action Program. Therefore, Event Notice 45331 is being retracted.
"The NRC resident has been notified."
Notified the R2DO (Blamey).