Investigation into uranium transport from URENCO to Framatome

The French regulatory body ASN and the Authority are both conducting investigations into an anomaly that occurred with a transport container holding a cylinder with uranium hexafluoride (UF6). This anomaly was found after a transport on 21 December 2023.

Enlarge image container waarin verrijkt uranium wordt verpakt voor transport
Image: ©ASN

No immediate consequences for safety

Transport departed from the URENCO enrichment facility in Almelo and was en route to the Framatome nuclear fuel factory in Romans-sur-Isère, France. Although the anomaly did not result in any immediate consequences for the safety of workers or the environment, it still should not have occurred in accordance with legislation, which is why we are investigating what went wrong.

Five loose ball lock pins

Cylinders holding UF6 are shipped in overpacks type UX-30. This overpack is a steel capsule secured with multiple ball lock pins. Upon arrival, it was discovered that five ball lock pins were not secured. There was no danger to personnel and the environment. There were still sufficient safety measures in place for keeping the uranium inside the cylinder. It is also as yet unclear whether or not the ball lock pins had been loose on the road.

This anomaly is not permitted according to legislation. If, for example, an accident or fire occurs during transport, then the transport container will not work as effectively in terms of protecting the cylinder. As a result, it was not in compliance with the high safety requirements that apply to this type of transport. UF6 is used in the production process of fissionable material for nuclear reactors.

Investigation and proposals for improvement

French regulator ASN and the Authority have tasked both Framatome and URENCO with investigating what went wrong during the transport. We will also conduct our own investigation. Due to the fact that the anomaly was discovered in France, French regulator ASN has taken on the investigation of the notification made by Framatome. As URENCO made a notification to us, we will be investigating the part of the journey that took place in the Netherlands. Our investigation will take place based on legislation and regulations and the licence we issued for this transport. 

Based on the results from these investigations, URENCO and/or Framatome will issue proposals for the improvement of their internal control processes in order to prevent recurrence. If it turns out that the transport was not conducted in accordance with the rules, than we may move on to enforcement.

Rated as INES 1 notification

ASN has also assessed this notification in accordance with the INES scale. The INES (International Nuclear and Radiological Event Scale) is an international scale that indicates the severity of an accident or incident involving radiation in the form of a number. In this case, ASN rated the notification as INES 1.

This indicates an anomaly as regards the safety requirements without an immediate threat to safety. As the Authority, we also assessed the notification in accordance with the INES scale and we agree with the ASN rating.

As soon as the results of the investigations are known, we will share the conclusions on our website.