Remotely-operated equipment designed to recover radioactive particles from the seabed has been demonstrated successfully offshore at Dounreay.
Two companies – Fathoms Ltd and Land and Marine Project Engineering Ltd – tested their systems during separate trials.
Both showed they were capable of detecting and retrieving particles from the offshore sediment.
Each system involved particle detection and recovery equipment mounted on a tracked crawler.
An umbilical cord to a workboat on the surface enabled each company to control the devices.
The results of each trial will now be evaluated in detail as part of the process to award one or more contracts to allow clean-up of the seabed to commence this summer.
Earlier this year, following extensive public consultation, the site announced its intention to begin seabed clean-up.
The programme is aimed at recovery of particles from the area of seabed polluted with the most hazardous fragments of irradiated nuclear fuel released historically from Dounreay.
It is currently expected to take four summers to complete initial clean-up of the target area, followed by further work to demonstrate the effectiveness of the clean-up.
In the meantime, monitoring of local beaches continues, subject to access.