Browse wiki
Jump to navigation
Jump to search
100 +
The following is a summary of information … The following is a summary of information that was provided by the licensee via phone and fax:</br>Millstone Power Station Unit 3 is submitting a 60-day telephonic notification in lieu of a licensee event report (LER) submittal as allowed by 10 CFR 50.73 (a)(1) for an invalid system actuation reportable under 10 CFR 50.73(a)(2)(iv)(A).</br>On May 6, 2025, at approximately 2108 EDT, while Millstone Power Station Unit 3 was in mode 5 during a refueling outage, an invalid safety injection (SI) signal was initiated. The actuation was not the result of intentional manual actuation and not in response to actual plant conditions requiring safety system operation. This resulted in the automatic start of both emergency diesel generators (EDGs), and the complete initiation on both trains of the following: main steam line isolation, containment isolation phase 'A', and safety injection signal. No injection into the reactor coolant system occurred, and the EDGs remained unloaded. All equipment not administratively locked out responded as designed, and the plant remained stable throughout the event. Control room operators responded in accordance with appropriate operating procedures and restored the affected systems. This notification is made pursuant to the reporting requirements specified in 10 CFR 50.73(a)(2)(iv)(A) for an invalid actuation of one of the systems listed in 10 CFR 50.73(a)(2)(iv)(B)- including safety injection signal, containment isolation signal, and start of both emergency diesel generators.</br>There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector was notified of the event.ident Inspector was notified of the event. +
01:08:00, 7 May 2025 +
57,793 +
11:38:00, 2 July 2025 +
01:08:00, 7 May 2025 +
The following is a summary of information … The following is a summary of information that was provided by the licensee via phone and fax:</br>Millstone Power Station Unit 3 is submitting a 60-day telephonic notification in lieu of a licensee event report (LER) submittal as allowed by 10 CFR 50.73 (a)(1) for an invalid system actuation reportable under 10 CFR 50.73(a)(2)(iv)(A).</br>On May 6, 2025, at approximately 2108 EDT, while Millstone Power Station Unit 3 was in mode 5 during a refueling outage, an invalid safety injection (SI) signal was initiated. The actuation was not the result of intentional manual actuation and not in response to actual plant conditions requiring safety system operation. This resulted in the automatic start of both emergency diesel generators (EDGs), and the complete initiation on both trains of the following: main steam line isolation, containment isolation phase 'A', and safety injection signal. No injection into the reactor coolant system occurred, and the EDGs remained unloaded. All equipment not administratively locked out responded as designed, and the plant remained stable throughout the event. Control room operators responded in accordance with appropriate operating procedures and restored the affected systems. This notification is made pursuant to the reporting requirements specified in 10 CFR 50.73(a)(2)(iv)(A) for an invalid actuation of one of the systems listed in 10 CFR 50.73(a)(2)(iv)(B)- including safety injection signal, containment isolation signal, and start of both emergency diesel generators.</br>There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector was notified of the event.ident Inspector was notified of the event. +
Has query"Has query" is a predefined property that represents meta information (in form of a <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Subobject">subobject</a>) about individual queries and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
00:00:00, 2 July 2025 +
Modification date"Modification date" is a predefined property that corresponds to the date of the last modification of a subject and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
11:20:04, 7 July 2025 +
11:38:00, 2 July 2025 +
true +
false +
56.438 d (1,354.5 hours, 8.062 weeks, 1.855 months) +
01:08:00, 7 May 2025 +
URL"URL" is a <a href="/Special:Types/URL" title="Special:Types/URL">type</a> and predefined property provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a> to represent URI/URL values.