ENS 55506: Difference between revisions

v t e ENS Event
19:33 Oct 4, 2021
Title	Degraded Condition Discovered on Reactor Vessel Head Penetration
Event Description	At 1433 CDT, on October 4, 2021, Arkansas Nuclear One, Unit 2 (ANO-2) completed the analysis related to an indication revealed on head penetration 46 during Reactor Vessel Closure Head inspections. It was determined the indication is not acceptable under ASME code requirements. The indication displays characteristics consistent with primary water stress corrosion cracking. No leak path signal was identified during ultrasonic testing. The plant was in cold shutdown at 0 percent power and in Mode 6 for a refueling outage at the time of discovery. Repair actions will be completed prior to plant startup from the outage. This condition has no impact to the health and safety of the public. This report is being made in accordance with 10 CFR 50.72(b)(3)(ii)(A) for degradation of a principal safety barrier. This is the only indication that is currently present, however, if additional indications are found, they will also be repaired prior to the plant startup. The NRC Senior Resident Inspector has been notified.

ENS 55506 +/-
Where
Arkansas Nuclear Arkansas (NRC Region 4)
Reporting

10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded
Time - Person (Reporting Time:+0.43 h0.0179 days <br />0.00256 weeks <br />5.89014e-4 months <br />)
Opened:	Derek Mosher 19:59 Oct 4, 2021
NRC Officer:	Howie Crouch
Last Updated:	Oct 4, 2021
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v • d • e

v t e Emergency Notification System
Arkansas Nuclear with 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded
WEEKMONTHYEAR2024-05-20T20:53:00 [Table view]
[ENS list for Arkansas Nuclear]

@@ Line 21: / Line 21: @@
 This report is being made in accordance with 10 CFR 50.72(b)(3)(ii)(A) for degradation of a principal safety barrier. This is the only indication that is currently present, however, if additional indications are found, they will also be repaired prior to the plant startup.
 The NRC Senior Resident Inspector has been notified.
-| URL = https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2021/20211005en.html#en55506
+| URL = https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2021/20211006en.html#en55506
 }}{{unit info
 | Unit = 2

Latest revision as of 07:30, 6 October 2021