Event Notification Report for June 02, 2021

EN Revision Imported Date: 6/3/2021

EN Revision Text: AGREEMENT STATE REPORT - OVERDOSE AND WRONG TREATMENT SITE

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

"On May 12, 2021, licensee notified the [Radiologic Health Branch] RHB of a possible medical event which occurred on May 10, 2021 involving a Gamma Knife patient who likely received a dose greater than 0.5 Sv (50 rem) to a tissue other than the treatment site and over 50% of the expected dose to that site from the procedure if the administration had been given in accordance with the written directive. No further details have been provided at this time. The licensee is currently investigating and will provide a full report within 15 days. RHB is investigating this event."

California Item Number: 051221

* * * RETRACTION ON 1 JUNE 2021 AT 1454 EDT FROM L. ROBERT GREGER TO JOANNA BRIDGE * * *

The following was received via e-mail from the state of California via e-mail:

"The licensee's initial dose calculation performed on the impacted non-target tissue was made to a non-dimensional point adjacent to the target tissue. Upon further licensee consideration, the non-target dose calculation was performed on the 1.55 cc non-target tissue (muscle) most impacted by a planning error for the gamma knife treatment. The revised calculation resulted in a dose to the non-target muscle tissue of 140 rad (1.4 Gy) compared to the 120 rad (1.2 Gy) that the 1.55 cc non-target muscle tissue would have received had the planning error not occurred. Therefore, the Medical Event criterion was not exceeded."

Notified R4DO (Groom) and NMSS Events (by email).

A Medical Event may indicate potential problems in a medical facility's use of radioactive materials. It does not necessarily result in harm to the patient.

EN Revision Imported Date: 6/3/2021

EN Revision Text: AGREEMENT STATE REPORT - LOST DEVICE

The following was received from the South Carolina Department of Health and Environmental Control (the Department) via email:

"The South Carolina Department of Health and Environmental Control was notified on 05/25/21, that a strontium-90 medical eye applicator was lost or missing. The eye applicator is an Atlantic Research Corporation Model B-1 eye applicator, serial number 300, with a maximum activity of 50 millicuries. The licensee is reporting that the last inventory listed the source activity at 15.25 millicuries. During a recent inspection conducted by the Department, the licensee was unable to provide disposal records of the medical eye applicator. The licensee is now reporting the loss of the strontium-90 medical eye applicator. This event is still under investigation by the South Carolina Department of Health and Environmental Control."

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

EN Revision Imported Date: 6/3/2021

EN Revision Text: FITNESS FOR DUTY REPORT

A licensed operator 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.

EN Revision Imported Date: 6/3/2021

EN Revision Text: 60-DAY TELEPHONIC NOTIFICATION OF INVALID ACTUATION OF A GENERAL CONTAINMENT ISOLATION SIGNAL AFFECTING MORE THAN ONE SYSTEM

"This 60-day telephone notification is being made per the reporting requirements specified by 10 CFR 50.73(a)(2)(iv)(A) and 10 CFR 50.73(a)(1) to describe an invalid actuation of the 2A Reactor Protection System (RPS). On April 1, 2021, at 1302 (CDT), Browns Ferry Unit 2, 2A RPS [Motor Generator] MG set tripped causing a half scram. Unit 2 experienced an unexpected trip of the 2A RPS MG Set that resulted in automatic Primary Containment Isolation System (PCIS) Group 2, 3, 6, and 8 isolations and Trains A, B, and C Standby Gas Treatment (SGT) and Train A Control Room Emergency Ventilation (CREV) starts. At the time of the event, Unit 2 was in a refueling outage and the rods were already fully inserted. All systems responded as expected.

"Plant conditions which initiate PCIS Group 2 actuations are Reactor Vessel Low Water Level (Level 3) or High Drywell Pressure. The PCIS Group 3 actuations are initiated by Reactor Vessel Low Water Level (Level 3) or Reactor Water Cleanup Area High Temperature. The PCIS Group 6 actuations are initiated by Reactor Vessel Low Water Level (Level 3), High Drywell Pressure, or Reactor Building Ventilation Exhaust High Radiation (Reactor Zone or Refuel Zone). The PCIS Group 8 actuations are initiated by Low Reactor Vessel Water Level (Level 3) or High Drywell Pressure. At the time of the event, these conditions did not exist; therefore, the actuation of the PCIS was invalid.

"Based on the troubleshooting conducted, the cause was determined to be a loose wiring connection in the motor circuit. The lugs were replaced with ring lugs. Operations reset the 2A RPS Half Scram and PCIS in accordance with 2-AOI-99-1 on April 1, 2021, at 1324 CDT thus correcting the condition and returning RPS to service.

"There were no safety consequences or impact to the health and safety of the public as a result of this event.

"This event was entered into the Corrective Action Program as Condition Report 1683358.

"The NRC Resident Inspector has been notified of this event."