ENS Event | |
|---|---|
18:56 Dec 11, 2019 | |
| Title | Potential Tornado Missile Vulnerabilities |
| Event Description | On December 11, 2019, at 1356 EST, it was concluded that certain safety-related equipment is vulnerable to design basis tornado missiles which could render the equipment inoperable and not able to perform its design function. This applies to the following Technical Specification equipment:
1. Component cooling water piping for the 'A' spent fuel cooling water system heat exchanger. This heat exchanger is vulnerable to a horizontal missile traveling through the roll-up door, which would challenge operability of the Technical Specification required component cooling system equipment. 2. All three (3) emergency service water pumps and their diesel fuel oil supply tank. The emergency service water pumps and diesel fuel oil tank are vulnerable to a horizontal missile penetrating the missile screens. 3. Certain component cooling water system pump discharge piping is vulnerable from a vertical missile penetrating the auxiliary building roof. 4. The Unit 1 auxiliary feedwater (AFW) system pumps and the pump suction and discharge piping are vulnerable to a missile traveling through the screens on the sides and roof of the main steam valve house. This vulnerability also exists for the Unit 2 AFW. This condition puts Unit 1 and 2 into Technical Specification 3.01 which requires the units to be in hot shutdown within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in cold shutdown within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. The NRC Resident Inspector has been notified. |
| Where | |
|---|---|
Surry  Virginia (NRC Region 2) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | |
| Time - Person (Reporting Time:+-3.83 h-0.16 days <br />-0.0228 weeks <br />-0.00525 months <br />) | |
| Opened: | Alan Bialowas 15:06 Dec 11, 2019 |
| NRC Officer: | Andrew Waugh |
| Last Updated: | Dec 11, 2019 |
| 54437 - NRC Website
Loading map... | |
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 554592021-09-13T22:22:00013 September 2021 22:22:00
[Table view]10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition of Fire Safe Shutdown Equipment ENS 544372019-12-11T18:56:00011 December 2019 18:56:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Potential Tornado Missile Vulnerabilities ENS 407702004-05-22T01:46:00022 May 2004 01:46:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Due to Auxiliary Feedwater Not Being in Compliance with Justification for Continued Operation (Jco). ENS 403892003-12-12T16:19:00012 December 2003 16:19:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Both Trains of Auxiliary Feewater Were Declared Inoperable for One Hour and 22 Minutes. ENS 402922003-11-03T22:20:0003 November 2003 22:20:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Non-Conservatism in Design Methodology for Loss of Rcp (Reactor Coolant Pump) Seal Cooling 2021-09-13T22:22:00 | |