Funding issues which had held up a radiation monitoring scheme in Dumfries and Galloway have been resolved.
A deal to monitor for particles from Sellafield has been agreed
Tests were ordered after the discovery of an increase in radioactive particles on shores in North Cumbria.
Environmentalists had voiced fears that the work was being delayed by debate over who should meet £100,000 costs.
The Nuclear Decommissioning Authority and the Scottish Environment Protection Agency have now agreed a deal brokered by the Scottish Government.
The breakthrough has been welcomed by South of Scotland MSP Alasdair Morgan.
He said the tests would ensure that a "sensible precaution" could go ahead.
"The continuation of radiation monitoring on the Solway coast is important," he said.
"If it uncovers nothing then it gives valuable reassurance to the public.
"If, on the other hand, it reveals that there is a problem, it should be much easier to get action to have that problem addressed."
Sepa has identified sites at Powfoot, Southerness and Kirkcudbright where the tests will be carried out.
The monitoring will be in addition to regular checks already carried out around the Chapelcross nuclear plant in Annan.