ENS 52592
ENS Event | |
|---|---|
14:00 Mar 5, 2017 | |
| Title | Planned Ultrasonic Test on Previously Repaired Reactor Vessel Penetration Did Not Meet Acceptance Criteria |
| Event Description | On 3/5/2017 at 0800 [CST], during the Byron Station Unit 1 refueling outage, it was determined that the results of a planned Ultrasonic (UT) examination performed on a previous repaired penetration of the reactor vessel head did not meet applicable acceptance criteria. These indications are not in the reactor coolant pressure boundary; however they are very near the previously repaired J-groove weld. The indication will be addressed prior to returning the vessel head to service. The examination was being performed to meet the requirements of 10 CFR 50.55a(g)(6)(ii)(D) and ASME Code Case N-729-1 to ensure the structural integrity of the reactor vessel head pressure boundary.
This event is being reported under 10 CFR 50.72(b)(3)(ii)(A) for 'Any event or condition that results in the condition of the nuclear power plant, including its principal safety barriers, being seriously degraded.' The licensee has notified the NRC Resident Inspector. Exelon Generation Company, LLC is also notifying the NRC Division of Component Integrity or its successor, by use of this ENS Report, of changes in indication(s) or findings of new indications(s) in the penetration nozzle or J-groove weld beneath a seal weld repair, or new linear indications in the seal weld repair, prior to commencing repair activities. See also EN #52591
Byron Event Notification 52952, made on March 05, 2017, reported two indications on one reactor head penetration. On March 06, 2017, ultrasonic examination identified two additional indications on the same penetration nozzle, (P-76). Additionally, two indications were identified on a second penetration nozzle (P-74), and one indication was identified on a third penetration nozzle (P-77). The indications on these three penetrations are all of the same type and none are within the reactor vessel head pressure boundary. This event is being reported under 10 CFR 50.72(b)(3)(ii)(A) for 'Any event or condition that results in the condition of the nuclear power plant, including its principal safety barriers, being seriously degraded.' The NRC Resident Inspector has been notified. Exelon Generation Company, LLC is also notifying the NRC Division of Component Integrity or its successor, by use of this ENS Report, of changes in indication(s) or findings of new indications(s) in the penetration nozzle or J-groove weld beneath a seal weld repair, or new linear indications in the seal weld repair, prior to commencing repair activities. Notified R3DO (Jeffers) |
| Where | |
|---|---|
Byron  Illinois (NRC Region 3) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded | |
| LER: | 05000454/LER-2017-001 |
| Time - Person (Reporting Time:+2.08 h0.0867 days <br />0.0124 weeks <br />0.00285 months <br />) | |
| Opened: | Jamie Getchius 16:05 Mar 5, 2017 |
| NRC Officer: | Howie Crouch |
| Last Updated: | Mar 6, 2017 |
| 52592 - NRC Website | |
WEEKMONTHYEARENS 558572022-04-23T13:54:00023 April 2022 13:54:00
[Table view]10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Ultrasonic Examination Results - Reactor Vessel Head Penetration ENS 525922017-03-05T14:00:0005 March 2017 14:00:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Planned Ultrasonic Test on Previously Repaired Reactor Vessel Penetration Did Not Meet Acceptance Criteria ENS 525912017-03-03T23:05:0003 March 2017 23:05:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Previous Overlay Repair Did Not Meet Acceptance Criteria ENS 514102015-09-19T01:00:00019 September 2015 01:00:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Reactor Vessel Head Penetration Repair Did Not Meet Acceptance Criteria ENS 505172014-10-08T00:00:0008 October 2014 00:00:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Ultrasonic Testing Reveal Degraded Condition on One Control Rod Drive Mechanism Penetration ENS 483112012-09-15T00:00:00015 September 2012 00:00:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Degraded Condition Due to Indications on Reactor Vessel Head During Dye Penetrant Test ENS 466862011-03-19T13:00:00019 March 2011 13:00:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Ultrasonic Examination Results in Indications on Two Reactor Head Penetrations 2022-04-23T13:54:00 | |