ENS Event | |
|---|---|
20:45 May 8, 2014 | |
| Title | Postulated Hot Short Fire Event That Could Adversely Impact Safe Shutdown Equipment |
| Event Description | A review of industry operating experience regarding the potential for secondary fires being caused by DC Motor control circuit wiring has determined the described condition to be applicable to Nine Mile Point Unit 1 resulting in a potentially unanalyzed condition with respect to 10 CFR 50 Appendix R analysis requirements. The original plant wiring design and configuration for the containment isolation valve IV-33-04 does not include separate over current protection for the power and control wiring. The only protection for the control circuit wiring is provided by the power circuit fuses.
In the postulated event, a fire in the reactor building at the DC MOV could cause one of the control circuit wires to short and potentially over heat creating a secondary fire in the raceway system in a different fire zone. The secondary fire could adversely affect safe shutdown equipment and potentially cause the loss of the ability to conduct a safe shutdown as required by 10 CFR 50 Appendix R. This event entered into the Nine Mile Point corrective action program as Condition Report (CR) 2014-004630. This condition is being reported in accordance with 10 CFR 50.72(b)(3)(ii)(B). Interim compensatory measures (i.e., fire zone inspections) have been implemented for affected areas of the plant. The licensee has notified the State and the NRC Resident Inspector. |
| Where | |
|---|---|
Nine Mile Point  New York (NRC Region 1) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | |
| LER: | 05000220/LER-2014-002 Regarding Unanalyzed Condition Due to Unfused Motor Operated Valve Control Circuit |
| Time - Person (Reporting Time:+0.2 h0.00833 days <br />0.00119 weeks <br />2.7396e-4 months <br />) | |
| Opened: | Gretchen Carter 20:57 May 8, 2014 |
| NRC Officer: | Dong Park |
| Last Updated: | May 8, 2014 |
| 50098 - NRC Website
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Unit 1 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
WEEKMONTHYEARENS 500982014-05-08T20:45:0008 May 2014 20:45:00
[Table view]10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Postulated Hot Short Fire Event That Could Adversely Impact Safe Shutdown Equipment ENS 494642013-10-22T18:00:00022 October 2013 18:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Postulated Hot Short Fire Event That Could Adversely Impact Safe Shutdown Equipment ENS 468272011-05-06T17:00:0006 May 2011 17:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Changes in Fuel Vendor Calculation Methodology to Comply with the Eccs Performance Requirements of 10 Cfr 50.46(B) ENS 439902008-02-16T00:02:00016 February 2008 00:02:00 10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat, 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Potential Inoperability of Emergency Core Cooling Systems Due to an Unalalyzed Condition ENS 407492004-05-14T13:17:00014 May 2004 13:17:00 Other Unspec Reqmnt, 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Change in the Methodology Used by Ge/Gnf to Demonstrate Compliance with Eccs Performance Requirements 2014-05-08T20:45:00 | |