ENS 57949: Difference between revisions

v t e ENS Event
18:47 Sep 24, 2025
Title	Automatic Reactor Trip
Event Description	The following information was provided by the licensee via phone and email: "On September 24, 2025, at 1347 CDT, Arkansas Nuclear One, Unit 1, (ANO-1) experienced an issue with the X-01B main phase transformer which led to an automatic trip on reactor protection system (RPS). "ANO-1 is currently stable in mode 3, maintaining pressure and temperature with the P-1A and P-1B main feedwater pumps and steaming to the main condenser. All rods inserted and systems functioned as expected. "There is no radiological release on either unit as a result of this event. "This report satisfies the reporting criteria of 10 CFR 50.72(b)(2)(iv)(B) and 10 CFR 50.72(b)(3)(iv)(A) for the reactor protection system actuation. "The NRC Senior Resident Inspector has been notified. "Unit 2 was not affected." The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: ANO-1 retains access to all normal sources of offsite power.

ENS 57949 +/-
Where
Arkansas Nuclear Arkansas (NRC Region 4)
Reporting

10 CFR 50.72(b)(2)(iv)(B), RPS Actuation
Time - Person (Reporting Time:+-1.07 h-0.0446 days <br />-0.00637 weeks <br />-0.00147 months <br />)
Opened:	Brandon Weaver 17:43 Sep 24, 2025
NRC Officer:	Ernest West
Last Updated:	Sep 24, 2025
57949 - NRC Website Loading map... {"minzoom":false,"maxzoom":false,"mappingservice":"leaflet","width":"350px","height":"250px","centre":false,"title":"","label":"","icon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"zoom":6,"defzoom":14,"layers":["OpenStreetMap"],"image layers":[],"overlays":[],"resizable":false,"fullscreen":false,"scrollwheelzoom":true,"cluster":false,"clustermaxzoom":20,"clusterzoomonclick":true,"clustermaxradius":80,"clusterspiderfy":true,"geojson":"","clicktarget":"","imageLayers":[],"locations":[{"text":"\u003Cb\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003E\u003Ca class=\"mw-selflink selflink\"\u003EENS 57949\u003C/a\u003E - \u003Ca href=\"/Arkansas_Nuclear\" title=\"Arkansas Nuclear\"\u003EArkansas Nuclear\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003EAutomatic Reactor Trip\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 57949 - Arkansas Nuclear\n","link":"","lat":35.31055555555555,"lon":-93.23084444444444,"icon":"/w/images/7/79/Entergy_icon.png"}],"imageoverlays":null}
v • d • e

v t e Emergency Notification System
Arkansas Nuclear with 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation
WEEKMONTHYEAR2025-09-24T18:47:00 [Table view]
[ENS list for Arkansas Nuclear]

@@ Line 16: / Line 16: @@
 | event date = 09/24/2025 13:47 CDT
 | last update date = 09/24/2025
-| title =
+| title = Automatic Reactor Trip
-| event text =
+| event text = The following information was provided by the licensee via phone and email:  "On September 24, 2025, at 1347 CDT, Arkansas Nuclear One, Unit 1, (ANO-1) experienced an issue with the X-01B main phase transformer which led to an automatic trip on reactor protection system (RPS).  "ANO-1 is currently stable in mode 3, maintaining pressure and temperature with the P-1A and P-1B main feedwater pumps and steaming to the main condenser.  All rods inserted and systems functioned as expected.  "There is no radiological release on either unit as a result of this event.  "This report satisfies the reporting criteria of 10 CFR 50.72(b)(2)(iv)(B) and 10 CFR 50.72(b)(3)(iv)(A) for the reactor protection system actuation.  "The NRC Senior Resident Inspector has been notified.  "Unit 2 was not affected."  The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: ANO-1 retains access to all normal sources of offsite power.
 | URL = https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2025/20250925en.html#en57949
 }}{{unit info

Revision as of 06:45, 25 September 2025