ENS 50128
ENS Event | |
|---|---|
15:00 May 21, 2014 | |
| Title | Unanalyzed Condition Involving Fire Safe Shutdown Capability |
| Event Description | This notification is to report a condition involving degraded control power wiring that resulted in an adverse impact on the ability to perform Fire Safe Shutdown for a postulated fire in the Main Control Room / Cable Spreading Room (MCR/CSR) complex. Therefore, this notification is being made pursuant to 10CFR 50.72(b)(3)(ii)(B).
At approximately 1100 hours0.0127 days <br />0.306 hours <br />0.00182 weeks <br />4.1855e-4 months <br /> [EDT], based on inspections being performed as part of an extent-of-condition review, Engineering personnel concluded that a degradation existed involving transfer / isolation switches that potentially impacted the ability to mitigate an Appendix R fire postulated to occur in the MCR/CSR complex. During scheduled maintenance outage windows on March 6, 2014 and May 5, 2014, broken wires were identified and repaired while the associated systems were out of service. Based on completion of the extent of condition walkdowns today, an additional location was identified, raising the potential that this condition existed for a longer period of time. The wiring degradation is limited to the capability of using Shutdown Method 'D' as described in the Peach Bottom Atomic Power Station Fire Protection Program. Shutdown Methods 'A', 'B' and 'C' used for other postulated fire areas were not affected by this condition. The postulated fire would have had to cause the normal control power fuses to fail for the issue to impact the safe shutdown function. Compensatory measures have been established until the condition is corrected. The NRC Resident Inspector has been informed of this notification. In the event of fire resulting in a loss of control power, compensatory measures will allow restoration of control power by replacing blown fuses. The compensatory measures are detailed in a temporary change to the MCR/CSR complex fire response procedure. The condition will be repaired during future equipment outages at the earliest opportunity. |
| Where | |
|---|---|
Peach Bottom  Pennsylvania (NRC Region 1) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | |
| LER: | 05000277/LER-2014-001 |
| Time - Person (Reporting Time:+2.65 h0.11 days <br />0.0158 weeks <br />0.00363 months <br />) | |
| Opened: | Adam Frain 17:39 May 21, 2014 |
| NRC Officer: | Daniel Mills |
| Last Updated: | May 21, 2014 |
| 50128 - NRC Website
Loading map... {"minzoom":false,"maxzoom":false,"mappingservice":"leaflet","width":"350px","height":"250px","centre":false,"title":"","label":"","icon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"zoom":6,"defzoom":14,"layers":["OpenStreetMap"],"image layers":[],"overlays":[],"resizable":false,"fullscreen":false,"scrollwheelzoom":true,"cluster":false,"clustermaxzoom":20,"clusterzoomonclick":true,"clustermaxradius":80,"clusterspiderfy":true,"geojson":"","clicktarget":"","imageLayers":[],"locations":[{"text":"\u003Cb\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003E\u003Ca class=\"mw-selflink selflink\"\u003EENS 50128\u003C/a\u003E - \u003Ca href=\"/Peach_Bottom\" title=\"Peach Bottom\"\u003EPeach Bottom\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003EUnanalyzed Condition Involving Fire Safe Shutdown Capability\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 50128 - Peach Bottom\n","link":"","lat":39.75920833333333,"lon":-76.26879444444444,"icon":"/w/images/b/be/Constellation_icon.png"}],"imageoverlays":null} | |
Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
Unit 3 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
WEEKMONTHYEARENS 569572024-02-09T18:22:0009 February 2024 18:22:00
[Table view]10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition - Inadequate Fuses for Fuel Pool Cooling ENS 532652018-03-15T19:24:00015 March 2018 19:24:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Failure to Meet Appendix R Requirements ENS 524782017-01-09T20:30:0009 January 2017 20:30:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident, 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Emergency Diesel Generators Non-Conforming with Licensing Basis for Tornado Generated Missiles ENS 501282014-05-21T15:00:00021 May 2014 15:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Involving Fire Safe Shutdown Capability ENS 474422011-11-16T00:52:00016 November 2011 00:52:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition High Pressure Coolant Injection Steam Supply Valve Cable Unprotected During Postulated Fire 2024-02-09T18:22:00 | |