ENS 43292
From kanterella
Jump to navigation
Jump to search
ENS Event | |
|---|---|
11:30 Apr 9, 2007 | |
| Title | Seismic Monitoring System Out of Service |
| Event Description | On April 9, 2007, at approximately 0730 hours0.00845 days <br />0.203 hours <br />0.00121 weeks <br />2.77765e-4 months <br />, the keyswitch for the Seismic Monitoring System was discovered in the off position, rendering the Seismic Monitoring System unavailable. The system has apparently been in this configuration since March 29, 2007, when deficiencies were found during routine calibration checks. The ability to declare an Unusual Event per Emergency Action Level 8.A.1 would not be significantly hampered by this event, because this declaration would be based on either personnel feeling an earthquake, or detection via the Seismic Monitoring System. However, the unavailability of the Seismic Monitoring System could potentially hamper the operators in determining the magnitude of an earthquake in order to determine if it reached Operating Basis Earthquake levels or Safe Shutdown Earthquake levels. Therefore, this could potentially hamper the declaration of an Alert or Site Area Emergency, respectively, per Emergency Action Levels 8.A.2 or 8.A.3. Therefore, this event is being considered reportable per 10 CFR 50.72(b)(3)(xiii), as it results in a loss of emergency assessment capability. Compensatory measures are being established to obtain an off-site source of this information in a timeframe that can support timely declaration of an emergency.
The licensee will notify the NRC Resident Inspector.
At time 0639 on 4/10/2007 the Seismic Monitoring System Instrumentation was reset. The Seismic Monitoring System is now FUNCTIONAL. With the SMA-3 Key Switch in the OPERATE position and the system RESET, the Seismic signal processing system and output devices are functioning to provide a STA SEISMIC INSTR ON alarm and to indicate if an OBE or SSE threshold has been exceeded. Therefore, the emergency assessment capability to declare an ALERT for EAL 8.A.2 or a Site Area Emergency for EAL 8.A.3 is restored. The Seismic Monitoring System remains INOPERABLE pending completion of DB-MI-04222, Seismic Instrumentation Calibration." R3DO (S. Burgess) notified. NRC Resident Inspector will be notified of this update by the licensee. |
| Where | |
|---|---|
Davis Besse  Ohio (NRC Region 3) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | |
| Time - Person (Reporting Time:+3.78 h0.158 days <br />0.0225 weeks <br />0.00518 months <br />) | |
| Opened: | Thomas Phillips 15:17 Apr 9, 2007 |
| NRC Officer: | John Knoke |
| Last Updated: | Apr 10, 2007 |
| 43292 - NRC Website | |
Unit 1 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
WEEKMONTHYEARENS 501432014-05-26T06:52:00026 May 2014 06:52:00
[Table view]10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Control Room Overhead Annunciator Malfunction ENS 502522014-05-21T07:36:00021 May 2014 07:36:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Control Room Overhead Annunciator Malfunction ENS 495462013-11-17T17:33:00017 November 2013 17:33:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness All Control Room Annunciators in Alarm ENS 476702012-02-16T18:42:00016 February 2012 18:42:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Spds Greater than Eight (8) Hours Due to Hard Drive Failure ENS 432922007-04-09T11:30:0009 April 2007 11:30:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Seismic Monitoring System Out of Service ENS 431642007-02-14T01:12:00014 February 2007 01:12:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Offsite Communications Capability Due to a Power Outage in Toledo, Ohio ENS 412862004-12-23T11:14:00023 December 2004 11:14:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Response Capability ENS 407342004-05-07T16:00:0007 May 2004 16:00:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Emergency Preparedness Capability Due to Inability to Activate Sirens 2014-05-26T06:52:00 | |
Retrieved from "https://kanterella.com/w/index.php?title=ENS_43292&oldid=426977"