ENS 50075

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v t e ENS Event
15:40 Apr 30, 2014
Title	Postulated Hot Short Fire Event Could Adversely Impact Safe Shutdown Equipment
Event Description	Based on a review of industry operating experience, it was identified that each unit has two un-fused DC control circuits for non safety-related DC motors which are routed from the turbine building through other separate fire areas including the Control Room. The DC breakers used to protect the motor power conductors are insufficient to protect the control conductors for these circuits. It is postulated that a fire induced short in one fire area could adversely impact safe shutdown equipment by overheating the cable and causing a secondary fire in other fire areas where the cable is routed. At Unit 1, cables for the affected circuits are routed in the Turbine Building, Cable Spreading Area and Control Room. At Unit 2, cables for the affected circuits are routed in the Turbine Building, Normal Switchgear, Service Building Cable Tray Area, Cable Vault, Instrument Relay Room, Control Building West Communication Room, Control Building Cable Spreading Area and Control Room. The postulated secondary fires or cable failures are outside the assumptions of each unit's fire protection analysis. A preliminary investigation of the issue indicates that existing fire protection safe shutdown procedures could be used to safely shut down the plant if needed. This condition is reportable as an 8-hour report in accordance with 10 CFR 50.72(b)(3)(ii)(B). Interim compensatory measures will be implemented for affected areas of the plant. The NRC Resident Inspector has been notified.

ENS 50075 +/-
Where
Beaver Valley Pennsylvania (NRC Region 1)
Reporting

10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition
Time - Person (Reporting Time:+1.32 h0.055 days <br />0.00786 weeks <br />0.00181 months <br />)
Opened:	Robert Kristophel 16:59 Apr 30, 2014
NRC Officer:	Jeff Rotton
Last Updated:	Apr 30, 2014
50075 - NRC Website
v • d • e

v t e Emergency Notification System
Beaver Valley with 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition
WEEKMONTHYEAR2023-06-11T05:30:00 [Table view]
[ENS list for Beaver Valley]

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