Preparations were being finalised last night to refloat the cargo ship which has been stranded on rocks off Duncansby Head.
The salvage team had completed offloading part of the cargo of fertiliser aboard the Priscilla and was due to try to tow it clear between 10 and 11pm.
The 89-metre long vessel, with six crew, ran aground on the Pentland Skerries early on July 18 as it entered the Pentland Firth en route to the Cumbrian port of Silloth.
The salvage vessels yesterday completed removing 1350 tonnes of the 3300-tonne load of bulk fertiliser aboard the Dutch-registered ship. It was moved on to barges and transferred on to the Priscilla’s sister vessel, Alan Evita.
Hugh Shaw, the Secretary of State’s acting Representative for Maritime Salvage and Intervention, said the timing of the refloat operation depends on a combination of favourable weather and tidal conditions.
Once the 2280-tonne ship is hauled clear of the reef, it will be towed to a local harbour.
Mr Shaw said: “A number of locations are still being considered and the final decision will be made once the structural integrity of the vessel has been established.”
A temporary 1000-metre exclusion zone remains in place while the salvage operation is being carried out.