ENS 48339
ENS Event | |
|---|---|
12:55 Sep 25, 2012 | |
| Title | Technical Support Center Removed from Service for Maintenance |
| Event Description | On September 25, 2012, power was removed from various Technical Support Center (TSC) systems to perform planned system preventative maintenance (PM) and corrective maintenance (CM) activities. During these maintenance activities, the normal TSC and Operational Support Center (OSC) are unavailable for use during an emergency. The Plant Data Network (PDN) will not be available to the TSC. This will render the Safety Parameter Display System (SPDS), Emergency Response Facility Display System (ERFDS), Emergency Assessment and Response System (EARS) and the Post LOCA Sampling System in the TSC unavailable. System alarms and data displays will still be available to the plant operators in the Control Room. The expected duration of the power outage is approximately 39 hours4.513889e-4 days <br />0.0108 hours <br />6.448413e-5 weeks <br />1.48395e-5 months <br />.
As compensatory measures, the backup emergency response facilities will be manned during an emergency. This compensatory measure has been communicated to the emergency response organization. It is expected that appropriate assessment of plant conditions, notifications, and communications could still be made, if required, during the time that the normal TSC and OSC are unavailable. This report is being made in accordance with 10 CFR 50.72(b)(3)(xiii), which is any event that results in a major loss of emergency assessment capability, offsite response capability, or offsite communications capability. An update message will be provided when the emergency response facilities are restored. The licensee will notify the NRC Resident Inspector.
This is an update to EN #48339 report on September 25, 2012, where Pacific Gas & Electric company (PG&E) reported that a planned maintenance power outage caused the normal Technical Support Center (TSC) and Operational Support Center (OSC) to be unavailable for use during an emergency. PG&E has completed all preventative maintenance (PM) and corrective maintenance (CM) activities that required the power outage to the TSC and OSC and has completed the restoration of these emergency response facilities. Plant personnel have been notified that the normal emergency response facilities have been restored. PG&E personnel have informed the NRC Resident Inspector. Notified the R4DO (Werner). |
| Where | |
|---|---|
Diablo Canyon  California (NRC Region 4) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | |
| Time - Person (Reporting Time:+-3.15 h-0.131 days <br />-0.0187 weeks <br />-0.00431 months <br />) | |
| Opened: | Glenn Goelzer 09:46 Sep 25, 2012 |
| NRC Officer: | Bill Huffman |
| Last Updated: | Sep 27, 2012 |
| 48339 - NRC Website | |
Unit 1 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
WEEKMONTHYEARENS 533612018-04-24T10:57:00024 April 2018 10:57:00
[Table view]10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Containment Radiation Monitors Inoperable ENS 493342013-09-09T20:00:0009 September 2013 20:00:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Planned Partial Loss of Communications Capability in Technical Support Center ENS 491732013-07-03T07:00:0003 July 2013 07:00:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Emergency Response Communications Due to a Loss of Ancillary Power ENS 487862013-02-27T00:30:00027 February 2013 00:30:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Assessment Capability Due to Vital Inverter Maintenance ENS 486002012-12-18T02:04:00018 December 2012 02:04:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Plant Vent Continuous Radiation Monitors Inoperable ENS 483392012-09-25T12:55:00025 September 2012 12:55:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Technical Support Center Removed from Service for Maintenance ENS 481712012-08-09T17:00:0009 August 2012 17:00:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Emergency Operations Facility Data Network Maintenance ENS 443052008-06-19T03:15:00019 June 2008 03:15:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Meteorlogical Mixing Calculations Unavailable ENS 426402006-06-14T16:41:00014 June 2006 16:41:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Erds Inoperable ENS 413022004-12-31T11:15:00031 December 2004 11:15:00 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Loss of Emergency Notification Sirens 2018-04-24T10:57:00 | |