Event Notification Report for August 31, 2025
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
08/30/2025 - 08/31/2025
EVENT NUMBERS
57894
57894
Agreement State
Event Number: 57894
Rep Org: WA Office of Radiation Protection
Licensee: Terracon Consultants, Inc
Region: 4
City: Seattle State: WA
County: King
License #: WN-I0507-1
Agreement: Y
Docket:
NRC Notified By: Dane Blakinger
HQ OPS Officer: Ian Howard
Licensee: Terracon Consultants, Inc
Region: 4
City: Seattle State: WA
County: King
License #: WN-I0507-1
Agreement: Y
Docket:
NRC Notified By: Dane Blakinger
HQ OPS Officer: Ian Howard
Notification Date: 08/31/2025
Notification Time: 17:58 [ET]
Event Date: 08/31/2025
Event Time: 00:00 [PDT]
Last Update Date: 09/29/2025
Notification Time: 17:58 [ET]
Event Date: 08/31/2025
Event Time: 00:00 [PDT]
Last Update Date: 09/29/2025
Emergency Class: Non Emergency
10 CFR Section:
Agreement State
10 CFR Section:
Agreement State
Person (Organization):
Dixon, John (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
ILTAB, (EMAIL) (EMAIL)
Dixon, John (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
ILTAB, (EMAIL) (EMAIL)
EN Revision Imported Date: 9/30/2025
EN Revision Text: AGREEMENT STATE REPORT - STOLEN DENSITY GAUGE
The following information was provided by the licensee via email:
"On the morning of 8/31/2025, an employee of Terracon Consultants discovered that a portable nuclear gauge (Troxler model 3440) was stolen from their vehicle overnight. The gauge was stored in the bed of a pickup truck that had a canopy cover. The gauge was also chained to the bed of the truck. The vehicle was parked inside of a parking garage with camera surveillance. Unfortunately, the cameras were [decoys] and were not operating.
"An individual gained access to the gauge by breaking through a canopy window and using a bolt cutter to cut the chain securing the Troxler gauge. The density gauge was the only nuclear material stolen. A toolbox was also taken which contained various non-nuclear equipment.
"The employee contacted Seattle Police, who at 1401 [PDT], had not arrived on scene to generate a report. The licensee will ensure that a report is generated and work with local law enforcement to recover the gauge. A full report will follow within 30 days."
Device Information:
Manufacturer: Troxler
Model: CDCW556
Serial Number: 14086
Source Information:
Manufacturer: AEA Technology/QSA
Model: CDCW556 (Cs-137) and AMNV.997 (Am-241:Be)
Isotopes and Activity: 9 mCi of Cs-137, 44 mCi of Am-241:Be, 0.066 mCi of Cf-252
* * * UPDATE ON 09/29/2025 AT 1747 EDT FROM DANE BLAKINGER TO JOSUE RAMIREZ * * *
The Washington State Department of Health, Office of Radiation Protection provided a 30-day written report regarding the incident (WA-25-010).
The gauge has not been located at this time. The licensee has an open case with the Seattle Police Department. In addition, the gauge is being actively looked for by the licensee.
Notified R4DO (Vossmar), NMSS Event Notification (email), ILTAB (email), and CNSC (email).
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 Text: AGREEMENT STATE REPORT - STOLEN DENSITY GAUGE
The following information was provided by the licensee via email:
"On the morning of 8/31/2025, an employee of Terracon Consultants discovered that a portable nuclear gauge (Troxler model 3440) was stolen from their vehicle overnight. The gauge was stored in the bed of a pickup truck that had a canopy cover. The gauge was also chained to the bed of the truck. The vehicle was parked inside of a parking garage with camera surveillance. Unfortunately, the cameras were [decoys] and were not operating.
"An individual gained access to the gauge by breaking through a canopy window and using a bolt cutter to cut the chain securing the Troxler gauge. The density gauge was the only nuclear material stolen. A toolbox was also taken which contained various non-nuclear equipment.
"The employee contacted Seattle Police, who at 1401 [PDT], had not arrived on scene to generate a report. The licensee will ensure that a report is generated and work with local law enforcement to recover the gauge. A full report will follow within 30 days."
Device Information:
Manufacturer: Troxler
Model: CDCW556
Serial Number: 14086
Source Information:
Manufacturer: AEA Technology/QSA
Model: CDCW556 (Cs-137) and AMNV.997 (Am-241:Be)
Isotopes and Activity: 9 mCi of Cs-137, 44 mCi of Am-241:Be, 0.066 mCi of Cf-252
* * * UPDATE ON 09/29/2025 AT 1747 EDT FROM DANE BLAKINGER TO JOSUE RAMIREZ * * *
The Washington State Department of Health, Office of Radiation Protection provided a 30-day written report regarding the incident (WA-25-010).
The gauge has not been located at this time. The licensee has an open case with the Seattle Police Department. In addition, the gauge is being actively looked for by the licensee.
Notified R4DO (Vossmar), NMSS Event Notification (email), ILTAB (email), and CNSC (email).
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