ENS 57912: Difference between revisions

v t e ENS Event
02:50 Sep 10, 2025
Title	Enclosure Building Boundary Inoperable
Event Description	The following information was provided by the licensee via phone and fax: Entry into shutdown technical specification action statement due to an identified breach in ventilation ductwork. At 2250 EDT on September 9, 2025, it was discovered that there was degraded manway sealant on the manway to fire damper HV-298A. This degraded sealant results in a direct path from the enclosure building to the atmosphere, challenging the enclosure building boundary. This condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v)(C). There is no impact on the health and safety of the public or plant personnel. The plant is currently in a 24-hour technical specification action statement (3.6.5.2) for Unit 2. Unit 3 is not impacted and continues to operate at 100 percent power. The Resident Inspector has been notified.

ENS 57912 +/-
Where
Millstone Connecticut (NRC Region 1)
Reporting

10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material
Time - Person (Reporting Time:+2.55 h0.106 days <br />0.0152 weeks <br />0.00349 months <br />)
Opened:	Josh Lindsey 05:23 Sep 10, 2025
NRC Officer:	Eric Simpson
Last Updated:	Sep 10, 2025
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v • d • e

v t e Emergency Notification System
Millstone with 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material
WEEKMONTHYEAR		Secondary Containment Inoperable 2025-09-10T02:50:00 [Table view]
[ENS list for Millstone]

@@ Line 23: / Line 23: @@
 The plant is currently in a 24-hour technical specification action statement (3.6.5.2) for Unit 2.  Unit 3 is not impacted and continues to operate at 100 percent power.
 The Resident Inspector has been notified.
-| URL = https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2025/20250911en.html#en57912
+| URL = https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2025/20250912en.html#en57912
 }}{{unit info
 | Unit = 2

Revision as of 06:20, 12 September 2025