Event Notification Report for October 06, 2022

AGREEMENT STATE - STOLEN AND RECOVERED TROXLER GAUGE

The following information was provided by the California Department of Public Health (CDPH) via email:

"Twining Inc. reported the theft of a Troxler model 3430 # 30952 portable soils gauge to the Sacramento CDPH office via California OES (Office of Emergency Services) on 9/8/22. The gauge contains two sealed sources: Cs-137, 0.30 GBq (8mCi) and Am-241/Be, 1.48 GBq (40mCi). The theft occurred around 2230 PDT on 9/6/2022, from the gauge operator's home. A police report was made to a deputy with the Riverside County Sheriff's office on the morning of 9/7/2022. The gauge had an airtag attached to it for tracking purposes.

"On 9/22/2022, Maurer Technical Services, who calibrates these types of soils gauges was contacted by a person who indicated he had this gauge. The caller's name, phone number and address in Riverside were obtained. Maurer Technical verified the gauge's serial number belonged to Twining, Inc. and their office was notified. Staff from Twining's Riverside office went to pick-up the gauge and it was transferred back to the Ventura office, where it was evaluated and leak tested on 9/25/2022 (found to be not leaking). The Riverside County Sheriff's office was informed that the gauge was recovered. Additionally, the Radiologic Health Branch was also notified that the stolen gauge had been recovered.

"On 9/29/2022, it was discovered that a supervisor at ICE RHB had received the initial notification from the CDPH duty officer, but due to competing demands, failed to forward the report to the RHB South office for follow-up action and reporting to the NRC."

CA Event Number: 092222

THIS MATERIAL EVENT CONTAINS A 'Less than Cat 3' LEVEL OF RADIOACTIVE MATERIAL

Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf

60-DAY OPTIONAL TELEPHONIC NOTIFICATION OF INVALID ACTUATION OF CONTAINMENT ISOLATION VALVES

The following information was provided by the licensee via email:

"This 60-day optional telephone notification is being made in lieu of an LER submittal as allowed by 10 CFR 50.73(a)(1). This notification is made pursuant to the reporting requirements specified in 10 CFR 50.73(a)(2)(iv)(A) for invalid actuations of one of the systems listed in 10 CFR 50.73(a)(2)(iv)(B).

"At approximately 0628 Eastern Daylight Time (EDT) on August 6, 2022, an invalid actuation of group 6 Primary Containment Isolation Valves (PCIVs) (i.e., containment atmospheric control/monitoring and post accident sampling isolation valves) occurred. The group 6 isolation signal resulted from the reactor building ventilation radiation monitor `A' channel exceeding the setpoint value. This condition recurred at approximately 1305 EDT on August 12, 2022. In both instances, the `B' channel, located in the same plenum, remained steady and below the setpoint value through the entire event. This, along with readings made by radiation protection technicians, confirmed that there were no actual high radiation conditions in the reactor building exhaust in either instance. Following each invalid actuation, upon returning unit 2 reactor building ventilation to service, the `A' channel readings returned to be consistent with the `B' channel. It was determined that these invalid actuations likely resulted from degradation of circuit components associated with the radiation monitor. The `A' channel radiation monitor was replaced on September 22, 2022.

"During these two events, the PCIVs functioned successfully and the actuations were complete. The actuations were not initiated in response to actual plant conditions, they were not an intentional manual initiation, and there were no parameters satisfying the requirements for initiation of the system. Therefore, these events have been determined to be invalid actuations.

"These events did not result in any adverse impact to the health and safety of the public."

FITNESS FOR DUTY REPORT

A non-licensed supervisor had a confirmed positive during a random fitness-for-duty test. The employee's access to the plant has been terminated.

The NRC Resident Inspector has been notified.