Event Notification Report for September 12, 2021
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
09/11/2021 - 09/12/2021
EVENT NUMBERS
55457
55457
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
Power Reactor
Event Number: 55457
Facility: North Anna
Region: 2 State: VA
Unit: [1] [] []
RX Type: [1] W-3-LP,[2] W-3-LP,[3] M-4-LP
NRC Notified By: David McGowan
HQ OPS Officer: Thomas Kendzia
Region: 2 State: VA
Unit: [1] [] []
RX Type: [1] W-3-LP,[2] W-3-LP,[3] M-4-LP
NRC Notified By: David McGowan
HQ OPS Officer: Thomas Kendzia
Notification Date: 09/12/2021
Notification Time: 22:41 [ET]
Event Date: 09/12/2021
Event Time: 17:28 [EDT]
Last Update Date: 10/21/2021
Notification Time: 22:41 [ET]
Event Date: 09/12/2021
Event Time: 17:28 [EDT]
Last Update Date: 10/21/2021
Emergency Class: Non Emergency
10 CFR Section:
50.72(b)(3)(ii)(A) - Degraded Condition
10 CFR Section:
50.72(b)(3)(ii)(A) - Degraded Condition
Person (Organization):
MILLER, MARK (R2)
MILLER, MARK (R2)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | N | 0 | Cold Shutdown | 0 | Cold Shutdown |
EN Revision Imported Date: 11/19/2021
EN Revision Text: DEGRADED CONDITION IDENTIFIED WHILE UNIT SHUTDOWN
"On September 12, 2021, at 1728 EDT, with Unit 1 in Mode 5 (Cold Shutdown) while performing inspections of the North Anna Power Station Unit 1 reactor vessel head flange area, a weld leak was identified on the reactor vessel flange leak-off line that connects to the flange between the inner and outer head o-rings. Entered TRM 3.4.6 Condition B for ASME Code Class 1,2, and 3 components. With known leakage past the inner head o-ring, this condition is reported since the fault in the tubing is considered pressure boundary [Reactor Coolant System] leakage.
"This event is reportable in accordance with 10 CFR 50.72(b)(3)(ii)(A) for any event or condition that results in the condition of the nuclear power plant, including its principle safety barriers, being seriously degraded."
The NRC Resident has been notified.
* * * RETRACTION ON 10/21/21 AT 1153 EDT FROM DENNIS BRIED TO BRIAN P. SMITH * * *
"The condition identified in EN 55457, pursuant to 10 CFR 50.72 (b)(3)(ii)(A) has been evaluated, and has been determined not to be Reactor Coolant System (RCS) pressure boundary leakage. As such, the 8-hour report is being retracted, as it is not an event or condition that results in, 'the condition of the nuclear power plant, including its principal safety barriers, being seriously degraded.'
"The leakage was subsequently determined to be in a tubing connection downstream of the reactor vessel inner O-ring. Leakage past a seal or gasket is not considered to be pressure boundary leakage, as defined by Technical Specifications."
The NRC Resident Inspector has been notified.
Notified R2DO (Miller)
EN Revision Text: DEGRADED CONDITION IDENTIFIED WHILE UNIT SHUTDOWN
"On September 12, 2021, at 1728 EDT, with Unit 1 in Mode 5 (Cold Shutdown) while performing inspections of the North Anna Power Station Unit 1 reactor vessel head flange area, a weld leak was identified on the reactor vessel flange leak-off line that connects to the flange between the inner and outer head o-rings. Entered TRM 3.4.6 Condition B for ASME Code Class 1,2, and 3 components. With known leakage past the inner head o-ring, this condition is reported since the fault in the tubing is considered pressure boundary [Reactor Coolant System] leakage.
"This event is reportable in accordance with 10 CFR 50.72(b)(3)(ii)(A) for any event or condition that results in the condition of the nuclear power plant, including its principle safety barriers, being seriously degraded."
The NRC Resident has been notified.
* * * RETRACTION ON 10/21/21 AT 1153 EDT FROM DENNIS BRIED TO BRIAN P. SMITH * * *
"The condition identified in EN 55457, pursuant to 10 CFR 50.72 (b)(3)(ii)(A) has been evaluated, and has been determined not to be Reactor Coolant System (RCS) pressure boundary leakage. As such, the 8-hour report is being retracted, as it is not an event or condition that results in, 'the condition of the nuclear power plant, including its principal safety barriers, being seriously degraded.'
"The leakage was subsequently determined to be in a tubing connection downstream of the reactor vessel inner O-ring. Leakage past a seal or gasket is not considered to be pressure boundary leakage, as defined by Technical Specifications."
The NRC Resident Inspector has been notified.
Notified R2DO (Miller)