Event Notification Report for May 07, 2024

AGREEMENT STATE REPORT - LOST AND RECOVERED MOISTURE DENSITY GAUGE

The following was received from the California Department of Public Health (CDPH) via email:

"On Monday night, April 29, 2024, Converse Consultant's radiation safety officer (RSO) reported the loss of a Troxler moisture density gauge (model 3440, serial 31135) containing sealed sources of Cs-137 (8 mCi) and Am-241:Be (40 mCi). The loss was noticed by the authorized user (AU), after he returned to the Redlands office from a jobsite in Jarupa Valley. The AU admitted that he must have left the Troxler gauge on his tailgate when taking a phone call in the cab of his truck, then left the jobsite for the day and forgot to put the gauge back into its type A case before transport. The AU told the RSO he retraced his travel route but did not locate the gauge that night. The RSO notified the Riverside County Sheriff of the missing gauge and notified CDPH of the loss at 1843 [PDT]. Upon returning to the jobsite the next day, the construction workers found the gauge. Apparently, the gauge fell off the tailgate within the jobsite, and the construction workers found the gauge and held it in storage until the AU returned to the jobsite. The gauge handle was locked into the safe/shielded position when it fell off the tailgate, and the source rod remained in the shielded position after the fall. The gauge case and electronics sustained minor damage. The AU took the recovered gauge to a service provider (Maurer Technical Services) on April 30, 2024, for leak testing and damage assessment for the minor case/electronic damage. The licensee will report the leak test results to CDPH when they become available. The licensee will gather additional information for the follow up investigation and provide additional information to the CDPH as it becomes available."

California control number: 24-2488

LOST IODINE-125 IMPLANT SEED

The following is a synopsis of information provided by the licensee via phone call:

On 4/15/24, a 145 microcurie iodine -125 implant seed was lost. The seed was one of four seeds to be implanted for mammography. During the exam, it was discovered that only three seeds were implanted. Licensee staff verified that the seed was not implanted in the patient. A thorough survey of the room, linens, and trash was performed and did not yield the seed. Licensee staff can not verify that the seed was present in the needle prior to the procedure.

The patient and the prescribing physician were made aware of the missing seed. No negative effect on the patient is expected.

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

AUTOMATIC REACTOR TRIP DUE TO LOWERING STEAM GENERATOR WATER LEVEL

The following information was provided by the licensee via email and phone:

"At 0338 CDT, with the unit 1 in mode 1 at 6 percent power, the reactor automatically tripped due to lowering steam generator water level. The trip was uncomplicated with all systems responding normally post-trip. 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 an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(iv)(A) for an actuation of the auxiliary feedwater system.

"Operations responded using procedure 1BwEP-0 and stabilized the plant in mode 3. Decay heat is removed by steam dumps via the main condenser. 1A and 1B auxiliary feedwater pumps were actuated manually prior to the reactor trip in an attempt to restore steam generator water level. Unit 2 is not affected.

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