ENS Event | |
|---|---|
18:27 May 5, 2004 | |
| Title | Unusual Event Due to Loss of Offsite Power |
| Event Description | Unit 3 scrammed as a result of a loss of offsite power. An unusual event was declared and the state was notified at 1352 [EST]. A Group I, II, and III [isolation] was received. The Isolation Condenser was manually initiated for reactor pressure control. HPCI [High Pressure Coolant Injection] was manually initiated to control reactor water level. All systems operated as expected. The Unit 3 and 2/3 emergency diesel generators automatically started and closed on to their respective busses. The reason for the loss of offsite power is not know at this time. Switchyard work was in progress at the time of the event.
All control rods fully inserted into the core during the reactor scram. The licensee notified the NRC Resident Inspector.
At 1601 Dresden Station Unit 3 terminated from an Unusual Event for a loss of offsite power. Bus 8 in the 345 KV switchyard was restored from circuit breaker 4-8. Transformer 32 was energized and supplied to Bus 33 and 33-1. Bus 34 remains energized from the Unit 3 SBO diesel generator. Bus 34-1 remains powered from the Unit 3 emergency diesel generator. Actions are being taken to restore those busses to the normal offsite power source. Plant cooldown is in progress and the unit is proceeding to Mode 4. Reactor water level is being maintained by HPCI and reactor pressure is being controlled with HPCI and the Isolation Condenser. LPCI is running in the torus cooling mode of operation. The LCO action requirement for secondary containment inoperability was exited at 1630. The licensee notified the State and the NRC Resident Inspector. Notified DHS (McIntire), FEMA (M. Eaches), DIRO (Nieh), R3DO (Lipa) and NRR EO (Lyons). |
| Where | |
|---|---|
Dresden  Illinois (NRC Region 3) | |
| Reporting | |
| Emergency class: | Unusual Event |
| 10 CFR 50.72(a) (1) (i), Emergency Class Declaration | |
| Time - Person (Reporting Time:+-2.97 h-0.124 days <br />-0.0177 weeks <br />-0.00407 months <br />) | |
| Opened: | David Groneck 15:29 May 5, 2004 |
| NRC Officer: | Arlon Costa |
| Last Updated: | May 5, 2004 |
| 40727 - NRC Website
Loading map... | |
Unit 3 | |
|---|---|
| Reactor critical | Critical |
| Scram | A/R |
| Before | Power Operation (100 %) |
| After | Hot Shutdown (0 %) |
WEEKMONTHYEARENS 555272021-10-16T10:28:00016 October 2021 10:28:00
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