Event Notification Report for March 25, 2017
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
03/24/2017 - 03/25/2017
EVENT NUMBERS
52640
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
Power Reactor
Event Number: 52640
Facility: CALVERT CLIFFS
Region: 1 State: MD
Unit: [] [2] []
RX Type: [1] CE,[2] CE
NRC Notified By: ANDREW MCNEIL
HQ OPS Officer: KARL DIEDERICH
Region: 1 State: MD
Unit: [] [2] []
RX Type: [1] CE,[2] CE
NRC Notified By: ANDREW MCNEIL
HQ OPS Officer: KARL DIEDERICH
Notification Date: 03/25/2017
Notification Time: 09:28 [ET]
Event Date: 03/25/2017
Event Time: 01:42 [EDT]
Last Update Date: 03/30/2017
Notification Time: 09:28 [ET]
Event Date: 03/25/2017
Event Time: 01:42 [EDT]
Last Update Date: 03/30/2017
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(v)(D) - ACCIDENT MITIGATION
10 CFR Section:
50.72(b)(3)(v)(D) - ACCIDENT MITIGATION
Person (Organization):
BRICE BICKETT (R1DO)
BRICE BICKETT (R1DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | N | Y | 100 | Power Operation | 100 | Power Operation |
REFUELING WATER TANK LEVEL INADVERTENTLY LOWERED BELOW TS
"While performing a purification subsystem alignment on the Unit-2 Refueling Water Tank, an inadvertent transfer of Refueling Water Tank level to the common Spent Fuel Pool occurred. This transfer resulted in lowering Unit-2 Refueling Water Tank level below the Technical Specification [TS] required limit for the current mode of operation at 0142 [EDT] on 3/25/17. Upon recognition of the inadvertent transfer, Operations secured the lineup and restored Unit-2 Refueling Water Tank level to its normal operating band at 0225 on 3/25/17.
"This event is reportable under 10 CFR 50.72(b)(3)(v)(D) '...any event or condition that at the time of discovery could have prevented the fulfillment of the safety function structures or systems that are needed to mitigate the consequences of an accident.' With less than the required Technical Specification volume in the Refueling Water Tank, insufficient volume existed in the Refueling Water Tank to maintain 30 minutes of full flow Safety Injection, and subsequent continued pump operation after transition to recirculation mode of operation."
This level is required by Technical Specification 3.5.4.B and has a one hour action statement to restore level.
The NRC Resident Inspector has been notified.
* * * RETRACTION FROM KENT MILLS TO DONALD NORWOOD AT 1637 EDT ON 3/30/2017 * * *
"The purpose of this notification is to retract ENS notification 52640 made on March 25, 2017 for Calvert Cliffs. After further evaluation, it has been determined that the volume of water in the Unit 2 Refueling Water Tank was never below the TS required volume of 400,000 gallons. The evaluation considered the as-found condition of the level transmitter and the existing environmental conditions of the tank in determining the actual RWT water volume on the day of the event. Therefore, this event does not meet the criteria of 10 CFR 50.72(b)(3)(v)(D) and the ENS report is being retracted."
The licensee will notify the NRC Resident Inspector.
Notified R1DO (Cook).
"While performing a purification subsystem alignment on the Unit-2 Refueling Water Tank, an inadvertent transfer of Refueling Water Tank level to the common Spent Fuel Pool occurred. This transfer resulted in lowering Unit-2 Refueling Water Tank level below the Technical Specification [TS] required limit for the current mode of operation at 0142 [EDT] on 3/25/17. Upon recognition of the inadvertent transfer, Operations secured the lineup and restored Unit-2 Refueling Water Tank level to its normal operating band at 0225 on 3/25/17.
"This event is reportable under 10 CFR 50.72(b)(3)(v)(D) '...any event or condition that at the time of discovery could have prevented the fulfillment of the safety function structures or systems that are needed to mitigate the consequences of an accident.' With less than the required Technical Specification volume in the Refueling Water Tank, insufficient volume existed in the Refueling Water Tank to maintain 30 minutes of full flow Safety Injection, and subsequent continued pump operation after transition to recirculation mode of operation."
This level is required by Technical Specification 3.5.4.B and has a one hour action statement to restore level.
The NRC Resident Inspector has been notified.
* * * RETRACTION FROM KENT MILLS TO DONALD NORWOOD AT 1637 EDT ON 3/30/2017 * * *
"The purpose of this notification is to retract ENS notification 52640 made on March 25, 2017 for Calvert Cliffs. After further evaluation, it has been determined that the volume of water in the Unit 2 Refueling Water Tank was never below the TS required volume of 400,000 gallons. The evaluation considered the as-found condition of the level transmitter and the existing environmental conditions of the tank in determining the actual RWT water volume on the day of the event. Therefore, this event does not meet the criteria of 10 CFR 50.72(b)(3)(v)(D) and the ENS report is being retracted."
The licensee will notify the NRC Resident Inspector.
Notified R1DO (Cook).