Event Notification Report for February 22, 2019

AGREEMENT STATE REPORT - LOSS OF LICENSED MATERIAL

The following was received via email from the state of North Carolina:

"North Carolina Radiation Protection Branch (RMB) was notified on February 22, 2019, that a General Licensee could not account for two Microderm hand-held probes containing two sources each [25 micro Ci of Sr-90 and 100 micro Ci of Tl-204]. RMB has been in communications with the General Licensee to ascertain whether or not the devices containing the sources have been returned to the vendor or are indeed lost. At this time, this cannot be verified and the RMB anticipates more information to follow on March 4, 2019. Additional details to follow to complete this event report."

NC Event Tracking ID: 190007

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

INVALID ACTUATION OF A UNIT 1 CONTAINMENT ISOLATION LOGIC DUE TO A BLOWN FUSE

"This 60-Day telephone notification is being made per the reporting requirements specified in 10 CFR 50.73(a)(2)(iv)(A) to describe an invalid actuation of Limerick Generating Station Unit 1 containment isolation logic.

"On February 22, 2019, while performing work on the 1C Main Seam Line Rad Monitor a partial containment isolation occurred due to a blown fuse. The blown fuse caused a single channel 'C' isolation signal for the Refueling Area Ventilation Exhaust High Radiation and the Reactor Enclosure Ventilation Exhaust-High Radiation logic.

"The following systems had components that actuated due to the partial isolation:
- Plant Process Radiation Monitoring System
- Nuclear Boiler System
- Control Rod Drive Hydraulic System
- Containment Atmospheric Control System
- Primary Containment Instrument Gas System

"This event resulted in partial Group VIC and partial Group VIIIB isolations. All the components that would actuate on a single 'C' isolation signal responded as designed."

The licensee notified the NRC Resident Inspector.

AGREEMENT STATE REPORT - REPORTABLE EQUIPMENT FAILURE

The following information was received via E-mail:

"A reportable equipment failure occurred on February 22, 2019 at a panoramic irradiator licensee in Libertyville, IL. The equipment failure was not reported to Illinois Emergency Management Agency (IEMA), but identified during a February 6, 2020 routine inspection. The affected equipment has since been repaired and no impacts to health or security were identified.

"IEMA inspectors conducted a routine inspection at Isomedix Operations d/b/a Steris, Libertyville location, on February 6, 2020. During a review of licensee files, it was determined that on the evening of February 22, 2019, required safety equipment became disabled as a result of the cell flooding. This is reportable, at a minimum, under 32 Ill. Adm. Code 340.1220c2. Inspection findings indicate that on or about 1817 CST February 22, 2019, a coupler on a 2 inch sprinkler line in the maze of the cell broke during processing. The cell consequently flooded and began to flood the warehouse. An emergency console stop was executed at approximately 1821 CST and both racks submerged. At 1824 CST, the pool high water alarm was tripped. Inspector review of the console event log indicates within the next 80 minutes the smoke detector, exhaust fans, collision bar, inside roof plug, low air pressure, high temperature, main panel communications and loss of 110 VAC and 24VDC faults were logged.

"It was also noted that at 2024 CST on February 22, 2019, the source racks were moved back up. At 2024 CST, the deionizer radiation monitor alarmed. A number of alarms and faults continued until approximately 1121 CST on 2/23/19. Reportedly, up to four inches of water covered the pool and the entirety of the warehouse. The fire department was needed to shut off the main feeding the sprinklers. Inspection findings indicate, at a minimum, high and low water monitors as well as the deionizer radiation monitor were disabled due to the wiring being flooded and shorted in the trough. The wiring for multiple components were replaced and plumbers contracted to repair the sprinkler system the following day. The licensee has moved to a manually initiated dry fire suppression system. Dosimetry was evaluated and no unusual exposures noted. Interviews of staff involved indicate security systems were not impacted. Leak tests were performed on February 22, 2019. This incident remains under investigation.

"There is no evidence of intentional disruption of safety or security systems."

Event Report ID No.: IL200005