Event Notification Report for May 26, 2021

EN Revision Imported Date: 5/26/2021

EN Revision Text: AGREEMENT STATE REPORT - GAUGE DAMAGED
The following was received from the State of Arkansas via email:

"The Agreement State General Licensed Device licensee reported to the State of Arkansas, Arkansas Department of Health [Department], that a 0.59 mCi (0.022 GBq) Co-60 sealed source (Manufacturer: Berthold Technologies, Model Number: P2608-100, Sealed Source Serial Number: 54-01-05) used in a Berthold Technologies General Licensed Device (Manufacturer: Berthold Technologies, Model Number: LB300L, Serial Number: 15951-1189-10000) was damaged by the conveyor belt rubbing and wearing down the steel housing of the device and into the lead shielding. The damage was discovered by the licensee during a routine inventory and inspection on April 14, 2021. The licensee submitted the required report and photographs to the Agreement State on May 17, 2021 at approximately 1400 [CDT].

"Licensee took immediate corrective actions including stopping the conveyor belt, locked-out gauge, secured area and blocked off area to gauge, performed exposure surveys, and performed wipe tests to confirm no contamination. The damaged gauge will be disposed and will not be replaced according to the licensee. Licensee confirmed no public exposures, no employee exposures, and negative leak tests results.

"Corrective actions by licensee include, but not limited to: (1) storage in place of damaged gauge until the manufacturer removes and disposes the device from its location, (2) installation of a t-roller in front of other similar gauges along with welding it in place to prevent the conveyor belt from contacting a radiation gauge if a troughing idler failure occurs, (3) perform a monthly preventative maintenance inspection of conveyor belts and gauging systems and repair of any damaged or severely worn jointers, (4) perform a monthly inspection of the t-roller in front of the radiation gauges, and (5) perform inspections of the t-roller by the Site Radiation Safety Duty Officer to ensure conveyor belt clearance."

"The Department considers this incident to be closed."

Arkansas Event No.: AR-2021-004

EN Revision Imported Date: 5/26/2021

EN Revision Text: "On 5/24/21 at 0916 EDT, an Automatic Reactor Trip on Unit 1 occurred. All safety systems responded normally and the plant is currently stable in Mode 3 (Hot Standby) at normal operating temperature and pressure. Preliminary indications are that the unit trip was caused by a High Neutron Flux Rate detected by the Power Range Nuclear Instruments. Troubleshooting and investigation are ongoing to determine the initiating cause.

"Unit 2 is not impacted and remains stable in Mode 1 at 100 percent power.

"Due to the Reactor Protection System actuation while critical, this event is being reported as a four-hour non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B) and in accordance with 10 CFR 50.72 (b)(3)(iv)(A) as an event that results in a valid actuation of the AFW system.

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

No relief valves opened. All Rods fully inserted. Decay heat is being removed by Auxiliary Feedwater via the steam dumps. The plant is in a normal post-trip electrical line-up.

UNIT 2 CONTAINMENT LOCAL LEAK RATE AND AS-FOUND INTEGRATED OVERALL LEAKAGE RATE EXCEEDED ACCEPTANCE CRITERIA

"At 1751 EDT on May 25, 2021, it was determined the local leak rate test (LLRT) for the 2EMF-IN containment penetration did not meet 10 CFR 50 Appendix J requirements for both the inboard and outboard containment isolation valves (2MISV5230 and 2MISV5231). The LLRT was performed during the previous refueling outage at which time primary containment was not required to be operable. The leakage assigned to the penetration also resulted in total leakage exceeding the allowed overall leakage. The valves were repaired and retested satisfactory prior to entering the mode of applicability, This event is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(ii)(A),

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