ENS 52649

v t e ENS Event
07:10 Mar 30, 2017
Title	Loss of All Control Room Annunciators
Event Description	The Unit 1 DC Cook Nuclear Plant (CNP) Annunciator System failed on Thursday, March 30, 2017 at 0255 [EDT]. The failure resulted in a complete loss of all alarm function of the Annunciator System in the Unit 1 Control Room. Unit 2 was unaffected by this failure. At 0310 [EDT], an Unusual Event (UE) was declared due to System Malfunction S-6, Loss of Alarms or Indication, due to an unplanned loss of safety system annunciators and/or indications in the Control Room for greater than 15 minutes. The Unit 1 PPC [Plant Process Computer] and ERDS [Emergency Response Data System] remain functional and available. This notification is being made in accordance with 10 CFR 50.72(a)(1)(i) due to the declaration of an Emergency Classification specified in the licensee's approved Emergency Plan. The licensee has notified the NRC Resident Inspector, the State and local agencies. Notified DHS SWO, FEMA Ops Center, DHS NICC. Notified FEMA National Watch and Nuclear SSA via E-mail. * * UPDATE FROM MAX MILLER TO DONG PARK AT 0821 EDT ON 3/30/2017 * * * Unit 1 DC Cook Nuclear Plant Annunciator System has been returned to functional. Unusual Event Classification was terminated at 0817 EDT on 3/30/17. The NRC Resident Inspector will be notified. Notified R3DO (Cameron), NRR EO (Miller), and IRD (Grant). Notified DHS SWO, FEMA Ops Center, DHS NICC. Notified FEMA National Watch and Nuclear SSA via E-mail.

ENS 52649 +/-
Where
Cook Michigan (NRC Region 3)
Reporting
Emergency class:	Unusual Event
10 CFR 50.72(a) (1) (i), Emergency Class Declaration
Time - Person (Reporting Time:+-3.85 h-0.16 days <br />-0.0229 weeks <br />-0.00527 months <br />)
Opened:	Tim Siefer 03:19 Mar 30, 2017
NRC Officer:	Dong Park
Last Updated:	Mar 30, 2017
52649 - NRC Website
v • d • e

v t e Emergency Notification System
Cook with 10 CFR 50.72(a)(1)(i), Emergency Class Declaration
WEEKMONTHYEAR2022-01-06T15:44:00 [Table view]
[ENS list for Cook]

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