Home Owners in the Rossnowlagh area are again being urged to check their oil tanks for leaks.
Donegal County Council has previously confirmed that traces of what appears to be home heating oil have been detected seeping out from under the rock armour at the rear of Rossnowlagh beach.
The Council says the detection of home heating oil on Rossnowlagh beach is of concern to both the community and themselves.
A number of investigations have been conducted in the area and a leaflet drop has also been undertaken in order to try and determine the source of the pollution.
However, as yet the source has not been identified.
Home and business owners in the area are urged to check their oil tanks for leaks.
People are being asked that if you suspect you are losing oil or have filled your tank more often this year, to engage with a registered OFTEC technician to pressure test your supply lines and check your tank.
If leaks are detected, property owners are being urged to repair them as soon as possible.