Event Notification Report for December 30, 2020

EN Revision Imported Date: 12/30/2020

EN Revision Text: HIGH PRESSURE COOLANT INJECTION INOPERABLE

"At 2150 CST on 11/04/2020, it was discovered that Unit 1 High Pressure Coolant Injection System (HPCI) was INOPERABLE; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v), as an event or condition that at the time of discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to mitigate the consequences of an accident.

"During performance of 1-SR-3.5.1.7, HPCI Main and Booster Pump Set Developed Head and Flow Rate Test at Rated Reactor Pressure, Unit 1 HPCI was manually tripped by the control room operator due to local report of excessive shaking of the cooling water supply from the booster pump line.

"There was no impact to the safety of the public or plant personnel. The NRC Resident Inspector has been notified.

"CR 1650042 documents this condition in the Corrective Action Program."

The Unit is in a 14-day LCO 3.5.1(c). The RCIC System is operable.

* * * RETRACTION FROM MARK ACKER TO HOWIE CROUCH AT 1607 EST ON 12/29/2020 * * *

"ENS Event number 54983, made on 11/05/2020 is being retracted. NRC notification 54983 was made to ensure that the Eight-Hour Non-Emergency reporting requirements of 10 CFR 50.72 were met when Unit 1 HPCI was manually tripped by the control room operator due to a local report for excessive shaking of the cooling water supply from the booster pump line.

"A subsequent engineering evaluation concluded on 11/06/2020 there was reasonable assurance of operability with no additional intrusive maintenance performed and that the condition was bounded by a previous evaluation documented in [Condition Report] CR 1347736. As such, the circumstances discussed in the report did not result in any condition that at the time of discovery could have prevented the fulfillment of the safety function of structures of the system that are needed to mitigate the consequences of an accident. Therefore, this event is not reportable under 10 CFR 50.72(b)(3)(v).

"TVA's evaluation of this event is documented in the corrective action program.

"The licensee has notified the NRC Resident Inspector."

Notified R2DO (Miller).

DAMAGED NUCLEAR GAUGE

The following is a summary of information that was received via email:

At 1141 EST, on 12/19/20, an authorized user (AU) for the licensee determined that one of their portable nuclear gauges was damaged. The AU felt the index rod loosen and then break off when he went to retrieve the gauge from its transport case. The gauge had been used the day before at a jobsite and did not experience any accidents. The gauge had not been dropped and was in the possession of the AU at all times during this event. The source remained in the shielded position within the gauge throughout this event.

The AU contacted the radiation safety officer (RSO) and the gauge was transported to an authorized storage location. The RSO took measurements of the outer transport box surface (1 mR/hr) and the gauge surface (5 mR/hr). The gauge was placed into an authorized storage shed and readings at the surface of the shed were non-distinguishable from background.

The gauge was a Troxler 3440 (s/n: 16938) with an 8 mCi Cs-137 source and a 40 mCi Am-241/Be source.


NC event number: NC200023