Two cubes of diesel sludge were discovered on the Dungooley road on Thursday morning according to local Fine Gael councillor John Reilly.
Taking to Facebook the Councillor said:
"These cubes of diesel sludge were dump on the Dungooley road over night in a act of pure vandalism.
"The damage to the environment and water course to such a beautiful area can’t be counted."
It is understood the council have since taken away the containers.
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