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Event Notification Report for May 30, 2023

U.S. Nuclear Regulatory Commission
Operations Center

EVENT REPORTS FOR
05/29/2023 - 05/30/2023

EVENT NUMBERS
56544
Power Reactor
Event Number: 56544
Facility: Millstone
Region: 1     State: CT
Unit: [3] [] []
RX Type: [1] GE-3,[2] CE,[3] W-4-LP
NRC Notified By: Jon Daskam
HQ OPS Officer: Bill Gott
Notification Date: 05/30/2023
Notification Time: 08:34 [ET]
Event Date: 05/30/2023
Event Time: 04:46 [EDT]
Last Update Date: 05/31/2023
Emergency Class: Non Emergency
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS Actuation - Critical 50.72(b)(3)(iv)(A) - Valid Specif Sys Actuation
Person (Organization):
Cahill, Christopher (R1DO)
Power Reactor Unit Info
Unit SCRAM Code RX Crit Initial PWR Initial RX Mode Current PWR Current RX Mode
3 A/R Y 100 Power Operation 0 Hot Standby
Event Text
EN Revision Imported Date: 6/1/2023

EN Revision Text: REACTOR TRIP

The following information was provided by the licensee via email:

"At 0446 EDT on 5/30/2023, with Millstone Power Station Unit 3 operating at approximately 100 percent reactor power, an automatic reactor trip occurred due to a turbine trip caused by electrical protection. The reactor trip was uncomplicated and decay heat is being removed via steam dumps to the condenser. All systems responded as expected to the trip.

"Auxiliary feedwater actuated automatically as expected following the trip due to low-low levels in the steam generators.

"There was no risk to the public. There was no impact to Millstone Unit 2.

"This event is being reported as a four hour report under 10CFR50.72(b)(2)(iv)(B) as a condition that resulted in actuation of the reactor protection system while the reactor was critical, and as an eight hour report under 10CFR50.72(b)(3)(iv)(A) and 10CFR50.72(b)(3)(iv)(B) for actuation of the auxiliary feedwater system.

"The NRC Resident Inspector has been notified."