ENS 50899

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v t e ENS Event
23:20 Mar 16, 2015
Title	High Pressure Coolant Inject Declared Inoperable Following Scheduled Maintenance
Event Description	At 1820 on March 16th, 2015, the High Pressure Coolant Injection (HPCI) system steam lines were re-pressurized following scheduled maintenance. Upon restoration, an alarm was received that indicated condensate may exist in the steam line. The system responded as designed but the alarm did not clear as expected. Without assurance that the condensate has been removed from the HPCI steam line, HPCI remains inoperable for reasons other than the planned maintenance. As a result, this condition is being reported under 10CFR50.72(b)(3)(v)(D) as a condition that could have prevented fulfillment of the safety function at the time of discovery. The health and safety of the public was maintained as the plant was in a normal condition with no initiating event in progress. The NRC Resident Inspector has been notified. The licensee will also notify the State of Minnesota. * * RETRACTION FROM RANDY SAND TO DANIEL MILLS AT 1445 EDT ON 5/11/15 * * * On March 16, 2015, Northern States Power Minnesota reported a condition that could have prevented the fulfillment of a safety function under 10 CFR 50.72(b)(3)(v)(D). The High Pressure Coolant Injection (HPCI) System was declared inoperable for a reason other than planned maintenance due to the failure of the HPCI Steam Supply Drain Hi Level Bypass Level Switch to clear the high level alarm subsequent to actuation. An engineering evaluation was performed and concluded that the function of the primary pathway to remove condensate remained unchallenged by the condition present on the level switch. This conclusion was also validated via thermography with the HPCI steam supply pressurized and bypass valve open. The verification that the primary pathway was functional provides reasonable assurance that the HPCI steam supply was always clear of condensate supporting the ability of HPCI to perform its required safety function. Therefore, the condition present on the level switch did not render HPCI inoperable. The conclusions of the engineering evaluation provide the basis for retraction of the ENS report made on March 17. The NRC Resident Inspector has been notified. The licensee will also notify the State of Minnesota. Notified R3DO (Peterson).

ENS 50899 +/- *RETRACTED*
Where
Monticello Minnesota (NRC Region 3)
Reporting

10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident
Time - Person (Reporting Time:+3.62 h0.151 days <br />0.0215 weeks <br />0.00496 months <br />)
Opened:	Dana Anton 02:57 Mar 17, 2015
NRC Officer:	Steve Sandin
Last Updated:	May 11, 2015
50899 - NRC Website
v • d • e

v t e Emergency Notification System
Monticello with 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident
WEEKMONTHYEAR2022-05-13T16:11:00 [Table view]
[ENS list for Monticello]

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