ENS Event | |
|---|---|
17:45 Sep 22, 2007 | |
| Title | Pressure Boundary Leakage Discovered During Drywell Inspection |
| Event Description | As part of a planned outage for Browns Ferry Unit 3, initial drywell leak inspections were performed after shutdown (mode 3). This inspection identified a weld defect in Residual Heat Removal (RHR) piping. The defect was in a one inch test line near manually operated valve 3-74-638B. This is classified as pressure boundary leakage and the piping is rated as ASME code class 1. The leak rate was estimated by visual observation at less than 0.25 gpm. Investigation is continuing into the cause of the weld defect. Unit 1 and 2 remain at full power and are not affected by this event.
This event is reportable within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> under 10 CFR 50.72(b)(3)(ii)(A) and 10 CFR 50.73(a)(2)(ii)(A) as 'Any event or condition that results in the condition of the nuclear power plant, including its principal safety barriers, being seriously degraded.' The licensee plans to continue to Mode 4 (Cold Shutdown) as required by Tech Specs for pressure boundary leakage. The NRC resident inspector has been notified. |
| Where | |
|---|---|
Browns Ferry  Alabama (NRC Region 2) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded | |
| Time - Person (Reporting Time:+-1.17 h-0.0488 days <br />-0.00696 weeks <br />-0.0016 months <br />) | |
| Opened: | Joe Bennett 16:35 Sep 22, 2007 |
| NRC Officer: | Bill Huffman |
| Last Updated: | Sep 22, 2007 |
| 43659 - NRC Website
Loading map... | |
Unit 3 | |
|---|---|
| Reactor critical | Not Critical |
| Scram | No |
| Before | Hot Shutdown (0 %) |
| After | Hot Shutdown (0 %) |
WEEKMONTHYEARENS 564112023-03-15T03:57:00015 March 2023 03:57:00
[Table view]10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Reactor Coolant System (RCS) Boundary Degraded Condition ENS 563712023-02-18T10:39:00018 February 2023 10:39:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Degraded Condition ENS 562572022-12-03T16:00:0003 December 2022 16:00:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Degraded Condition Discovered on Shutdown Cooling Test Line ENS 557062022-01-16T05:20:00016 January 2022 05:20:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Degraded Condition Discovered on Shutdown Cooling Test Line ENS 539592019-03-26T15:30:00026 March 2019 15:30:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Report of Degraded Condition Due to Leaking Valve ENS 451072009-05-31T18:30:00031 May 2009 18:30:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Degraded Condition Due to Discovery of Pressure Boundary Leakage ENS 446802008-11-23T18:00:00023 November 2008 18:00:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Pressure Boundary Leak ENS 436592007-09-22T17:45:00022 September 2007 17:45:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Pressure Boundary Leakage Discovered During Drywell Inspection 2023-03-15T03:57:00 | |