ENS 56846

v t e ENS Event
08:14 Nov 10, 2023
Title	Manual Reactor Scram
Event Description	The following information was provided by the licensee via email: At 0118 EST, with Unit 1 in Mode 1 at 100 percent power, the reactor was manually scrammed due to degrading main condenser vacuum. The scram was not complex, with all systems responding normally post-scram. The main turbine bypass valves opened automatically to maintain reactor pressure. Operations responded and stabilized the plant. Reactor water level is being maintained via feedwater pumps. Decay heat is being removed by discharging steam to the main condenser using the turbine bypass valves. Unit 2 is not impacted. Due to Reactor Protection System actuation while critical, this event is being reported as a four-hour and eight-hour non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B) and 10 CFR 50.72(b)(3)(iv)(A). Unit 1 reactor is currently stable in mode 3. An investigation is in progress into the cause of the degrading condenser vacuum. There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.

ENS 56846 +/-
Where
Susquehanna Pennsylvania (NRC Region 1)
Reporting

10 CFR 50.72(b)(2)(iv)(B), RPS Actuation 10 CFR 50.72(b)(3)(iv)(A), System Actuation
Time - Person (Reporting Time:+-5 h-0.208 days <br />-0.0298 weeks <br />-0.00685 months <br />)
Opened:	Tony Lee 03:14 Nov 10, 2023
NRC Officer:	Dan Livermore
Last Updated:	Nov 10, 2023
56846 - NRC Website
v • d • e

v t e Emergency Notification System
Susquehanna with 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation
WEEKMONTHYEAR2023-03-23T21:36:00 [Table view]
[ENS list for Susquehanna]

Navigation menu