Event Notification Report for June 27, 2024

CONCURRENT REPORT FOR FIRE IMPAIRMENT

The following information was provided by the licensee via email:

"At approximately 2310 EDT on June 27th, the New Hanover County deputy fire marshal was notified that the site fire alarm system was impacted by multiple power surges from lightning. Specifically, the electric fire pump, while operational, could not communicate with the fire system. A fire watch was initiated and repairs to the system began. The electric fire pump communication was restored at approximately 0745 EDT on June 28th. The deputy fire marshal was notified of communication restoration. Because the New Hanover County deputy fire marshal was notified, a concurrent notification to the NRC Operations Center is being made per 10 CFR 70, Appendix A(c)."

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

The licensee plans to notify the NRC Region 2 office and the state of North Carolina concerning this event report.

SHUTDOWN REQUIRED BY TECHNICAL SPECIFICATIONS

The following information was provided by the licensee via email:
"At 0159 EDT on 6-27-24, DC Cook Unit 2 commenced a controlled shutdown to address identified leakage through 2-QRV-251, CVCS [chemical and volume control system] charging pumps discharge flow control valve, valve packing. The leakage started at 2303 EDT on 6-26-24 and was determined to be greater than the 10 gallons per minute limit per technical specification 3.4.13 allowable leakage. The leakage was determined to not be repairable at power.

"Per 10CFR 50.72(b)(2) this is a 4 hour non-emergency report for Technical Specification required shutdown."

The NRC Resident Inspector was notified.

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:
A normal shutdown is expected to be completed by 0900 EDT. There are no radiological releases. Unit 1 was not affected. There is no estimate for the time of the repairs.

AUTOMATIC START OF TURBINE DRIVEN AUXILIARY FEEDWATER PUMP

The following information was provided by the licensee email:

"On June 27, 2024, at 0804 [EDT], D.C. Cook Unit 2 had an automatic start of the turbine driven auxiliary feedwater pump (TDAFP) following a controlled down power and manual reactor trip at approximately 17 percent power. The automatic start of the TDAFP was due to a steam generator water level 'low low' signal following the reactor trip. The down power and trip were performed in accordance with normal shutdown procedures to comply with the required action C.1 of technical specification 3.4.13, 'reactor coolant system operational leakage.' Reference event notification number EN57194.

"An automatic start of the TDAFP is an eight hour report per 10CFR 50.72(b)(3)(iv)(A).

"Unit 2 is being supplied by offsite power. All control rods fully inserted. Steam generators are being fed by both motor driven auxiliary feedwater pumps. Decay heat is being removed via the steam dump system to the main condenser. Preliminary evaluation indicates plant systems functioned normally following the reactor trip. D.C. Cook Unit 2 remains in Mode 3 to repair the previously reported reactor coolant system leakage through valve 2-QRV-251, 'CVCS [chemical and volume control system] charging pumps discharge flow control' valve packing."

The NRC Resident Inspector has been notified.

TECHNICAL SPECIFICATION (TS) REPORTABLE OCCURRENCE

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

"On June 27, 2024, at 1037 EDT, the North Carolina State University (NCSU) PULSTAR reactor was shutdown due to channel failure of the N-16 detector. This channel is required during operations over 500 kW by TS 3.4a. The reactor was operating at 950 kW at the time of channel failure. The reactor operator promptly shutdown and secured the reactor. Due to the nature of an unscheduled shutdown, investigation as to the source of channel failure and remedy will be commenced. At this time, failure has been isolated to just the N-16 channel. As such, operations may continue with approval for restart by the director of the NCSU PULSTAR reactor at powers below 500 kW. To resume full operations, channel maintenance, required surveillances, and additional approval by the director of the NCSU PULSTAR reactor are required."

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

The N-16 channel provides a reference power level indication while adjustments are being made to other power level channels.

AGREEMENT STATE REPORT - LOST ELECTRON CAPTURE DETECTOR SOURCE

The following summary of information was provided by Colorado Department of Public Health and Environment, Radioactive Materials Unit (the Department) via phone and email:

On June 27, 2024, the Department was notified by the licensee (IEH-WAL Laboratories) of a missing source from an electron capture detector for gas chromatography (ECD-GC) (Agilent Technologies, ECD, Model: 1923369576, 15 mCi Ni-63). The discovery of the lost source was through an inventory check earlier in the day. The last record of the device was on February 21, 2024, at a location in Littleton, CO, where similar units were repaired or dispositioned. Searches at both the Greeley and Littleton locations were performed. This notification is being made to the NRC in accordance with Colorado Regulations Section 4.51.1.1.

Colorado Event Report ID: CO240015

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

AGREEMENT STATE REPORT - Y-90 UNDERDOSE

The following information was received from the Massachusetts Radiation Control Program (the Agency) via email:

"On 06/28/24 at 1430 EDT, the licensee reported a medical event under license 60-0096 for BWXT Medical Ltd. TheraSpheres Model TheraSphere Y-90 Glass Microsphere System (Sealed Source and Device Registry: NR-0220-D-131-S) for total administered activity that differed from prescribed treatment activity as documented in the written directive by 20 percent or more.

"The medical event was reported to the radiation safety officer (RSO) at 1430 EDT on 6/27/2024. The prescribed dose to the patient was 106.4 mCi over two fractions. The dose received by the patient was 68.5 mCi (60.4 mCi on the first fraction, and 8.1 mCi on the second fraction). This resulted in an under dose of 35.6 percent. The authorized user and prescribing physician have been notified. The licensee has not reported whether the patient has been notified.

"The Agency will follow up with licensee RSO to determine the event cause and corrective actions.

"The Agency considers this event open. The Agency will follow up with a special inspection of the licensee."


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.