Event Notification Report for May 14, 2024

AGREEMENT STATE REPORT - STUCK SHUTTERS

The following information was provided by the Arkansas Department of Health, Radiation Control Section (ADH) via email:

"On 4/25/2024, [the licensee] notified ADH by phone that, during semi-annual routine inspection, five Berthold process nuclear gauges were either stuck/seized or difficult to operate. All affected gauges were stuck in the open/operate position. A representative from Berthold reported to the site on 4/30/2024 and successfully cleaned/lubricated all shutter/operating mechanisms restoring normal operation to the affected gauges.

"The following gauges were affected:
"Berthold Model LB 7440-D-CR: SN 37624-12090: Cs-137 50 mci: (Unknown License)
"Berthold Model LB 330: SN 2868-11-89: Cs-137 24 mci: (Unknown License)
"Berthold Model LB 300L: SN 6001: Co-60 4.1, 0.7, 0.2 mci: (General License)
"Berthold Model LB 300: SN 7687: Co-60 1.8, 0.5, 0.2 mci: (Specific License)
"Berthold Model LB 300L: SN 17729-1396-10023: Cs-137 24 mci: (General License)

"Licensee corrective actions included flagging the gauges locally, involving management, notifying their safety department, and suspending any activity that would require access to the gauges until they were repaired.

"The licensee is evaluating disposal of the gauges and possible replacement.

"The licensee confirmed at 1020 CDT on 5/06/2024, that one LB 300 gauge shown above is a specific license gauge.

"The investigation is ongoing, and reporting will proceed in accordance with SA-300."

Arkansas Event Number: AR-2024-003

LOST TRITIUM EXIT SIGNS

The following information was provided by the licensee via telephone:

During an inspection in early March 2024, the licensee could not locate ten tritium exit signs. On May 7, 2024, after searching for the signs, the licensee declared the signs lost. The licensee does not know when the signs were lost. The total activity was 118.7 curies.

The licensee notified the NRC Region 4 inspectors.

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

MEDICAL EVENT - Y-90 OVERDOSE

The following information was provided by the licensee via telephone:

A patient had a written directive to receive 90 Gy of Y-90 TheraSpheres to the liver. When the order was entered into the system, the wrong activity was entered. The higher activity of 360 Gy Y-90 TheraSpheres was then administered to the patient. The calculated dose to the liver may exceed 50 rem.

The patient and referring physician were informed. No health effect or permanent functional damage is expected.

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.

AGREEMENT STATE REPORT - STUCK SOURCE

The following was received from the Texas Department of State Health Services (the Department) via email:

"On May 7, 2024, the Department was notified by the licensee that on May 1, 2024, one of its radiography crews was unable to fully retract a 82.92 curie iridium-192 source into a QSA 880D exposure device. The radiographers had cranked the source out to test a weld, but when they tried to retract the source back to the fully shielded position they could not. The radiographers immediately notified the licensee's site radiation safety officer (SRSO), set up new barriers, and warned other individuals in the area. After a licensee manager arrived at the location, it was determined that a bend in the guide tube was too sharp to allow the source to be retracted. Using a set of 6.5 foot tongs, the SRSO repositioned the guide tube, and a radiographer was able to return the source to the fully shielded position. No individual received an exposure that exceeded 100 millirem. Additional information will be provided as it is received in accordance with SA-300."

Texas Incident Number: 10104
Texas NMED Number: TX240014

OFFSITE NOTIFICATION

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

"At 2030 CDT on May 11, 2024, Arkansas Nuclear One, Unit 1 (ANO-1) determined that the State of Arkansas should be notified after greater than 100 gallons of refueling canal water overflowed from the borated water storage tank (BWST) onto the ground inside the protected area outside the ANO-1 Auxiliary Building. The activity for transferring water from the ANO-1 refueling canal to the BWST was stopped and the tank level was lowered to stop the overflow. None of the spilled liquid was introduced into a storm drain or other pathway to Lake Dardanelle. This condition did not exceed any NRC regulations or reporting criteria.

"Arkansas Nuclear One, Unit 2 (ANO-2) was unaffected by this event.

"This notification is being made as a four-hour, non-emergency notification for a notification of other government agency 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."

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers report guidance:
The area where the liquid spill occurred is being controlled and a spill remediation plan is in progress.

AUTOMATIC REACTOR TRIP

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

"At 1641 CDT on May 12, 2024, with Unit 2 in Mode 1 at 15 percent power, the reactor automatically tripped due to a unit auxiliary transformer lockout. During the trip, all control rods fully inserted. The cause of the transformer lockout is currently unknown. Emergency diesel generator (EDG) 21 and 23 actuated and all three engineered safety feature (ESF) busses were energized.

"All equipment responded as expected except for steam generator power operator relief valve (PORV) 2C which failed to open when required in automatic, and the load center (LC) E2A output breaker which failed to close automatically but was closed manually. Steam generator PORV 2C did open when placed in manual, although it subsequently failed to full open and was then closed. Primary system temperature and pressure are currently being maintained at 567 degrees/2235 psig following start of reactor coolant pumps 2A and 2D.

"Due to the reactor protection system actuation (RPS) while critical, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B). This event is also being reported per 10 CFR 50.72(b)(3)(iv)(A) as an event that resulted in a valid actuation of the emergency diesel generators. There was no impact to the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."

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

South Texas Project Unit 2 was in Mode 1 at 15 percent power due to performance of testing and analysis on the main turbine prior to the RPS actuation.

TECHNICAL SPECIFICATION VIOLATION

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

"During a routine source check on 5/10/2024, it was noted that three of the six iodine-131 processing hot cell radiation monitors were located incorrectly. Upon investigation, it was discovered that on 4/19/2024 the filter banks were switched between bank 'A' and bank 'B'. During this filter bank switch, the detectors monitoring the filter banks were also not changed. This led to processing iodine three times between 4/19/2024 and 5/10/2024 without meeting the conditions of Technical Specification 3.10.c regarding monitoring requirements. The event was corrected on 5/10/2024.

"Several detectors were monitoring the suite during the period from 4/19/2024 and 5/10/2024, including the off-gas (stack) radiation monitor per Technical Specification 3.10.c. Additional monitors were in service, including a duct monitor, in-room DAC monitors, and the remaining three iodine-131 processing hot cell radiation monitors. No in-service monitors indicated abnormal rises in iodine levels.

"After the detectors were returned to service in the correct location, it was noted that the readings on the filter banks were very low. These readings provide supporting evidence that they were not being loaded while the detectors were incorrectly located."

INOPERABILITY OF BOTH TRAINS OF UNIT 2 LOW HEAD SAFETY INJECTION

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

"At 0917 EDT on May 13, 2024, a control room operator erroneously rendered the `B' train of the Unit 2 residual heat removal (RHR) system inoperable. This occurred while the `A' train of the Unit 2 RHR system was out of service for preplanned maintenance. RHR serves as the low head safety injection (LHSI) subsystem for the emergency core cooling system (ECCS) and because of this, Unit 2 was without a required train of ECCS from 0917 EDT to 0921 EDT.

"No other equipment issues were identified.

"The LHSI subsystem is credited by the analysis for a large break loss of coolant accident at full power.

"This event is being reported pursuant to 10 CFR 50.72(b)(3)(v)(D).

"The NRC resident inspector has been notified.

"There is no release of radioactive material associated with this event."