Event Notification Report for November 23, 2022

EN Revision Imported Date: 11/23/2022

EN Revision Text: AGREEMENT STATE REPORT - GAMMA KNIFE MALFUNCTION

The following information was provided by South Carolina Department of Health & Environmental Control via email:
"The South Carolina Department of Health and Environmental Control was notified on 08/10/2022, during a follow-up of a routine inspection, that a Leksell Gamma Knife Perfexion gamma stereotactic radiosurgery unit had failed to function as designed. The licensee [Prisma Health Richland Hospital] is reporting that during routine maintenance that was conducted by the manufacturer on 11/01/2021, it was discovered that a sector was dragging and not transferring smoothly. The licensee is reporting that one of the sealed sources had slipped less than 1/8 inch within one of the source cavities of the Leksell Gamma Knife Perfexion unit. The sealed source is a Co-60 Elekta Model 43685 medical teletherapy source, with an estimated activity between 20-22 curies. The licensee is reporting the unit was repaired and source reseeded on 11/05/2021. The licensee is reporting no overexposures to workers, patients, or members of the public. All sealed sources were leak tested on 11/05/2021 and results indicated that no sources were leaking. This event is under investigation by the South Carolina Department of Health and Environmental Control."

* * * UPDATE ON 9/7/2022 AT 1158 EDT FROM ADAM GAUSE TO MICHAEL BLOODGOOD * * *
The following information was provided by South Carolina Department of Health & Environmental Control via email:

"The licensee has submitted a 30-day written report. The Co-60 Elekta Model 43685 medical teletherapy source serial number is NIW098 with an estimated activity of 20.6 Ci (0.7622 TBq) at the time of the event. On 11/05/2021, the manufacturer and service representative identified the bushing containing the source had slipped slightly from its sleeve. The bushing was visually inspected via remote camera and showed no damage. The bushing and source was reseeded into its sleeve on 11/05/2021. No patients were treated between 11/1/2021-11/10/2021. The licensee is reporting no overexposures or medical events. The licensee performed areas surveys (using a Fluke 451PYR, calibrated 04/08/21) on 11/03/21 and 11/05/21, records indicated dose rate readings that were consistent with the radiation levels in the sealed source and device registry for the Perfexion unit. The licensee also performed area contamination surveys/wipes (using a Capintec Captrac, calibrated 10/18/21) on 11/03/21 and 11/05/21, records indicated contamination levels below the licensee's removable contamination trigger limits. This event is still under investigation by the South Carolina Department of Health and Environmental Control."

Notified R1DO (Defrancisco) and NMSS Event Notification via email.

* * * UPDATE ON 11/22/2022 AT 1501 EST FROM ADAM GAUSE TO IAN HOWARD * * *
The following update was provided by the state of South Carolina via email:

"The manufacturer (Elekta, Inc.) submitted a report dated 10/14/22. The manufacturer's estimate of the effect on the dose rate is a reduction of about 0.3 percent for the 4 mm collimator with one loose bushing in the worst angle. The manufacturer's estimate of the effect on the delivered dose was 1.5 mGy less than planned. The licensee reported the typical patient dose range is 32-85 Gy. The manufacturer performed a root cause analysis in the report dated 10/14/22. The manufacturer determined that when pushing the bushing into the sleeve, the bushing can be slightly misaligned with the sleeve making it stick without the spring being properly activated. Later the bushing can come loose due to vibrations. The manufacturer determined this is what is likely to have happened here.

"The licensee's corrective actions included determining the root cause of the event, reseating the bushing and lubricating all sectors, determining no other bushings were loose/unseated, performing acceptance testing prior to treatment of the first patient after event, and having future source loadings confirm all source bushings are properly seated prior to turning the unit over for acceptance testing. The licensee did not identify any other instances where a source/bushing slippage had occurred. This event/investigation is closed."

Notified R1DO (Carfang) and NMSS Events Notification email group.

EN Revision Imported Date: 11/23/2022

EN Revision Text: AGREEMENT STATE REPORT - STUCK SHUTTERS

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

"The South Carolina Department of Health and Environmental Control was notified via telephone on 10/31/22 that three fixed gauging device shutters were stuck in the closed position. All three fixed gauging devices are Thermo Fisher Scientific Model 5197 gauging devices, serial numbers B7842, B7847, and B7841. The activity of each gauging device is 100 mCi of Cs-137. The licensee is reporting that all three fixed gauging devices are mounted 12-15 feet above accessible areas. No elevated exposure rates are being reported. Department inspectors will be dispatched to the facility. This event is still under investigation by the South Carolina Department of Health and Environmental Control."

South Carolina Event Number: To be assigned.

* * * UPDATE ON 11/22/2022 AT 1451 EST FROM ADAM GAUSE TO IAN HOWARD * * *
The following update was provided by the state of South Carolina via email:

"Department inspectors were dispatched to the facility and found the gauges as the licensee described. The gauges were expected to be repaired on 11/02/22. The licensee submitted a 30-day written report dated 11/11/22. The written report indicated the fixed gauging devices were repaired on 11/02/22. The licensee's corrective actions included repairing the fixed gauging devices and updating procedures to include examples of reporting requirements. This event is still under investigation by the South Carolina Department of Health and Environmental Control."

Notified R1DO (Carfang) and NMSS Events Notification email group.

AGREEMENT STATE REPORT - DAMAGED GAUGE

The following information was provided by the State of Ohio via email:

"The Ohio Department of Health (ODH) received a call on November 14, 2022, concerning a Troxler model 3241-C gauge [100 mCi Am-Be source], that was damaged in a fire at a job site in Wellston (Jackson County). The gauge was stored in a trailer at a temporary asphalt plant. The plant closed last week for the winter and the gauge was going to be removed this week. The fire destroyed the trailer and melted the plastic outer shell of the device. An ODH inspector responded to the site. The source was located under the remains of the trailer but is buried in the ashes from the trailer. The highest dose rate detected was 7mR/hr which indicates that the source is shielded by the lead in the device. A licensed service provider will be on site on November 15, 2022, to retrieve the source and transport it for disposal. The licensee will provide security at the site until the source is removed."

Ohio Item number: OH220011

AGREEMENT STATE REPORT - WRONG INITIAL DOSE TO PATIENT

The following report was received via email from the Tennessee Division of Radiological Health:

"Medical Physicist for Holston Valley Medical Center reported that a patient was mistakenly given all fractions of a cervical treatment on November 14, 2022. The patient was scheduled for five 600 centigray (cGy) fractions of Ir-192 for a total of 3000 cGy. The medical physicist misread the prescription and gave the full 3000 cGy in the initial dose. As of November 15, 2022, the patient had not been notified. However, the patient will be returning on November 16, 2022, for the next treatment.

"Corrective actions or reports will be updated with a report within 30 days."

Tennessee Event Number: TN-22-069

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.

NOTIFICATION OF ENVIRONMENTAL REPORT TO ANOTHER GOVERNMENT AGENCY

The following information was provided by the licensee via email:

"On 11/22/2022, Monticello Nuclear Generating Plant initiated a voluntary communication to the State of Minnesota after receiving analysis results for an on-site monitoring well that indicated tritium activity above the [Offsite Dose Calculation Manual] ODCM and Nuclear Energy Institute (NEI) Groundwater Protection Initiative (GPI) reporting levels. The source of the tritium is under investigation and the station will continue to monitor and sample accordingly. This notification is being made solely as a four-hour, non-emergency report for a Notification of Other Government Agency. This event is reportable in accordance with 10 CFR 50.72(b)(2)(xi). There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."