Event Notification Report for January 30, 2024

EN Revision Imported Date: 1/31/2024

EN Revision Text: MANUAL TRIP DUE TO LOWERING MAIN CONDENSER VACUUM
At 0525 EST, November 14, 2021, "Unit 2 was manually scammed by operations due to lowering main condenser vacuum. This resulted in PCIS (primary containment Isolation system) Group II/III isolation signals. All control rods inserted, and all systems operated as designed."

Unit 3 is unaffected and remains at 100 percent power in Mode 1.

The Resident Inspector was notified.

EN Revision Imported Date: 2/1/2024

EN Revision Text: AGREEMENT STATE REPORT - Y-90 MICROSPHERE MISADMINISTRATION

The following is a summary of information received via email from the Washington Office of Radiation Protection:

On the afternoon of Friday, January 19th, a Pluvicto (radiopharmaceutical) dose was not administered properly. A typical administered dose may have up to 2 to 4 mCi of residual activity after a 200 mCi administration. However, for this administration there was 43 mCi of residual activity and only 149 mCi of calculated administered activity for a 200 mCi prescribed dose. Pluvicto is a six fraction, six administration regimen with about six weeks between each administration, and this was the patient's fourth fractional dose. Treated as a single administration treatment, this constitutes a medical event as the dose administered activity of 149 mCi is more than 20% less than the 200 mCi prescribed dose. The final report will be sent in 15 days.

Washington Event Number: WA-24-003

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.

* * * UPDATE ON 1/29/2024 AT 1401 EST FROM BORIS TSENOV TO NATALIE STARFISH * * *
The following information is a synopsis of information provided by the Washington State Radioactive Materials Section:

A lutetium 177 (drug name: Pluvicto) dose was prescribed to be 200 mCi. The calculated dose administered to the patient was about 149 mCi, based upon the measured residual. The underdosing occurred due to a method of folding and crimping the intravenous tube with a hemostat and gauze instead of utilizing the kit provided clamp. The hospital supply chain of the intravenous kit was recently changed and the needed clamp was thought to be missing. To prevent future crimping of the intravenous tube, the use of hemostat and gauze will no longer be used.

This dose was the fourth dose of six prescribed to the patient, with six weeks between each administration. There is no expected change in the patient's treatment or prognosis based on the underdosing of the fourth fraction of six and no additional actions are required.

Final report will be sent in 15 days.

Washington Event Number: WA-24-003

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.

Notified R4DO (Agrawal) and NMSS (email).

TWO SUSPECTED ORPHAN GAUGES FOUND

The following information was provided by the Louisiana Department of Environmental Quality (LDEQ) via email:

"On January 22, 2024, at approximately 1400, Central Standard Time (CST), an unidentified nuclear gauge of roughly cylindrical dimensions and less than 30 cm in length and 12 cm in width was detected by the entrance gate radiation monitor at the Louisiana Scrap Metal facility (LA Scrap) located in Gibson, LA in Terrebonne Parish. Facility scrap surveyors were immediately dispatched to more close survey the suspected gauge using Ludlum Model 3 survey instruments with external probes. During this time an additional suspected nuclear gauge, similar in design and overall dimensions to the first, was discovered by the facility's scrap surveyors. Surface radiation readings of approximately 0.9 to 1.2 mR/hr were observed at the surface of both devices. No identifying markings, labels or tags were noted on the gauges' surfaces, and both devices appeared to have sustained significant corrosion to their housings, which nonetheless appeared intact. The devices were believed by the reporting party to have originated with scrap from the disassembly of a 220-foot marine vessel purchased by LA Scrap from a Florida scrap broker. The above incident was reported via the LDEQ Radiation Hotline at approximately 1335 CST on January 23, 2024. The facility is awaiting identification of the devices' isotope(s) (to be provided by the LDEQ) prior to contracting with BBP Sales, Louisiana Radioactive Material License, LA-10799-L01, for inspection, leak testing, packaging, and disposal of the devices.

"The facility environmental health and safety (EHS) manager, stated that the gauges have been enclosed in a bucket of moist dirt and secured within an area on site with restricted access. Facility workers were advised by the EHS manager to stay clear of the area in the meantime."

LA Event Report ID: LA240002

AGREEMENT STATE REPORT - STOLEN MOISTURE DENSITY GAUGE
The following information was provided by the California Department of Public Health Radiologic Health Branch (RHB) via email:

"On 1/23/24, California Governor's Office of Emergency Services (CAL OES), contacted RHB to report a stolen moisture density gauge. Per the CAL OES report, at around 2200 PST on 01/22/24, a portable gauge was stolen from the bed of a parked truck belonging to the reporting party.

"On 1/23/24, RHB contacted the reporting party (gauge user) and learned the following:

"The stolen gauge is a CPN Model 131, serial number, MD 00705803, containing 10 mCi of Cs-137 and 50 mCi of Am-241. On 1/22/24, around 2030 PST, the gauge user was feeling ill and was not able to return the gauge to the storage unit and decided to leave it in his work truck parked at his residence. On the next day morning (1/23/24) at around 0700, the user drove his truck to a job site in Palo Alto, CA, opened the cover of the bed of the truck and discovered that the gauge was stolen from the vehicle. There were no signs of a break-in, so the truck bed may have been left unlocked. The gauge storage box was chained through two handles and was attached to the bed of the truck. On 1/23/24, at around 1400 PST, the gauge user notified the Daily City Police Department of the stolen gauge (Report No. T24000071).

"RHB will be following up on this investigation."

CAL OES Report CENTRL No.: 24-0397





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: 2/1/2024

EN Revision Text: AUTOMATIC REACTOR SCRAM

The following information was provided by the licensee via email:

"At approximately 1202 EST on 01/29/24, unit 2 experienced a reactor scram caused by a main turbine trip. Investigation is still ongoing."

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

All control rods were fully inserted. The licensee indicated that the turbine trip may have been caused by a power load imbalance, however the cause of the incident is under investigation. The scram was not complex.

Decay heat is currently being removed thru bypass valves dumping to the main condenser. Initially unit 2 lost the use of the bypass valves due to lack of condenser vacuum. Unit 2 used the high pressure coolant injection (HPCI) system in the condenser storage tank (CST) to CST mode to remove decay heat. Residual heat removal was used to keep the torus cool. Condenser vacuum was regained and unit 2 is back to removing decay heat with the turbine bypass valves.

There was no impact to unit 3.

The licensee confirmed there was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.

* * *UPDATE ON 01/29/24 AT 1935 EST FROM PAUL BOKUS TO NATALIE STARFISH* * *

The following information was provided by the licensee via email:

Licensee adds 8-hour non-emergency 10 CFR 50.72(b)(3)(iv)(A) specified system actuation report to original 4-hour non-emergency 10 CFR 50.72(b)(2)(iv)(B) RPS Actuation report.
"At approximately 1202 EST on 01/29/24, unit 2 experienced a reactor scram by a main turbine trip. All control rods inserted. Reactor core isolation cooling system (RCIC) was manually initiated for level control. HPCI was manually initiated for pressure control. Primary containment isolation system (PCIS) Group II and III isolations occurred [specified system actuation]. Investigation is ongoing."

The NRC Resident Inspector has been notified.

HIGH PRESSURE CORE SPRAY FAILURE
The following information was provided by the licensee via email:
"At 1005 CST on January 29, 2024, Grand Gulf Nuclear Station was conducting surveillance testing on the high pressure core spray system. During testing, the 1E22F012 minimum flow valve failed to return to the full closed position. The valve went from full open indication to dual indication.

"The event is being reported in accordance with 10 CFR 50.72(b)(3)(v)(D) as an event or condition which could have prevented the fulfillment of a safety function.

"Troubleshooting is in progress.

"The NRC Senior Resident has been notified."

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

All off-site power is available. No other systems are out of service and there are no compensatory measures taken. There is no increase to plant risk.