Radioactive monitoring of beaches on the Scottish side of the Solway Firth is due to start next month.
The Solway Firth tests come after particles were found in Cumbria
It follows the discovery of radioactive particles from Sellafield on beaches in North Cumbria.
The Scottish Environment Protection Agency (Sepa) has identified sites at Powfoot, Southerness and Kirkcudbright where the tests will be carried out.
The work was due to start in August but was delayed because of a dispute over who should meet the £100,000 costs.
Monitoring will now begin on 12 December, after Sellafield Ltd agreed to pay the costs of the monitoring.
Specialist equipment, similar to that used to monitor beaches near the Dounreay plant at Caithness, will be brought in for the task.
The tests will be in addition to regular checks already carried out around the Chapelcross nuclear plant in Annan.