Event Notification Report for September 12, 2024

AGREEMENT STATE REPORT - FOUND SOURCE

The following information was provided by the Illinois Emergency Management Agency (the Agency) via telephone and email:

"On September 3, 2024, the Division of Radioactive Materials was notified that an Alnor Instruments dew point measurement device was located at a metal recycling facility in Bellwood, IL. The instrument was recovered by Agency staff and there was no indication of removable contamination. The device contains a 7 microcurie radium-226 foil that was manufactured and distributed by an Illinois specific licensee. An authorized service provider was contacted to assist in tracking down the original owner. The device was intact and no public exposures are anticipated as a result of this incident. If unable to locate the owner, this device will be incorporated in the Agency's orphan source recovery program and properly disposed of as low level radioactive waste. Updates to this report will be made as they become available."

Illinois report number: IL240020

AGREEMENT STATE - DAMAGED DENSITY GAUGE

The following information was provided by the North Carolina Department of Health and Human Services, Division of Health Service Regulation, Radioactive Materials Branch (the Department) via email:

"The licensee reported that around 1600 EDT on September 4, 2024, their portable nuclear gauge (PNG) was run over by another vehicle at a construction site. The PNG is a Troxler 3440 (serial number 25787), containing 8 millicuries of Cs-137 (serial number 20-2119) and 40 millicuries of Am-241/Be (serial number 41-9543). The licensee dispatched their recovery team immediately. They were able to retract the source rod back into the PNG with the source block closed. Readings taken around the gauge indicated no readings in excess of transportation index requirements. Additional surveys of the work area indicated the source was intact and in the safe position. The PNG was then transported to the manufacturer for repair.

"The Department's investigation is ongoing and this report will be followed up on to close and complete the record."

NC Event Number: NC240005

60-DAY NOTIFICATION OF INVALID SPECIFIED SYSTEM ACTUATION

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

"This 60-day telephone notification is being submitted in accordance with 10 CFR 50.73(a)(1) and 50.73(a)(2)(iv)(A). The event was an invalid actuation of the Unit 1 containment ventilation isolation (CVI) system.

"On August 3, 2024, at 0840 EDT, with Unit 1 at 100 percent power, train 'A' of the CVI system actuated due to an invalid signal from 1-RM-90-130, containment purge air exhaust monitor. 1-RM-90-130 was out of service for maintenance testing at the time of the invalid signal. The cause of the signal was determined to be the result of an installed multimeter timing out, creating a short in the actuation circuitry. The train 'A' CVI signal was a full actuation of that train and the system functioned as designed.

"Prior to and following the CVI alarm, all other radiation monitors were stable at their normal values; therefore, the CVI [actuation] was invalid. Control room operators performed appropriate checks and confirmed that all required automatic actuations occurred as designed. Subsequent completion of the maintenance instruction was successful. This event was entered into the corrective action program as CR 1948103.

"The NRC Resident Inspector was notified."

OFFSITE NOTIFICATION

The following information was provided by the licensee via email:

"On September 10, 2024, Columbia Generating Station determined that no more than approximately thirty (30) gallons of silicone oil was inadvertently released into a plant service water system due to a failed heat exchanger on a plant installed air compressor. The plant service water system returns water to a water basin that contains at a minimum 300,000 gallons of water. The water basin is connected to the Columbia River via a blowdown line. The compromised heat exchanger and compressor have been isolated and secured from the plant service water system. Although not confirmed, it is suspected that an unknown quantity of silicone oil may have been released to the Columbia River. A visual inspection of the basin did not identify any oil sheen or film, and there are no additional actions needed to mitigate this issue. It does not appear the oil released poses a threat to human health or the environment, however, because there could have been a discharge of an unknown quantity of silicone oil into the Columbia River, this matter is immediately reportable under [Revised Code of Washington] 90.56.280 to the U.S. Coast Guard National Response Center, Washington State Department of Ecology, and to the State of Washington Energy Facility Site Evaluation Council (EFSEC) under the site's National Pollutant Discharge Elimination System (NPDES) permit section S3.F.2.b.

"This condition is being reported pursuant to 10 CFR 50.72(b)(2)(xi) for notification of other government agencies concerning an event related to the health and safety of the public or protection of the environment. Notifications to off-site agencies are in progress."



The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:

The NRC resident inspector will be notified.