Limerick City and County Council says it is satisfied that the oil spill, which occurred near Tournafulla in County Limerick on Thursday afternoon is being contained with no negative impact on public water supplies.
Environmental specialists remain at the scene of the spill to remove oil-contaminated soil.
The clean-up process will continue over the weekend. Once completed, the Council says it will continue to monitor nearby watercourses to ensure there is no residual impact.
The Council confirmed that the spill occurred at 2pm on Thursday when a hydraulic oil tank attached to a mobile crane ruptured during the process of setting up the crane on site.