The Government has been fined €5 million by a European court for failing to comply with a 2008 ruling that an environmental assessment must be carried out on a wind farm.
The Court of Justice of the European Union handed down the judgment as a result of the construction of a wind farm at Derrybrien, Co Galway, without an environmental impact assessment being carried out.
The state has been ordered to pay an additional penalty payment of €15,000 per day from the date of delivery of the judgment in the present case until the date of compliance with the 2008 ruling.
In July 2008, the court ruled the Republic of Ireland had breached the environmental impact assessment directive as no study was carried out ahead of construction of the 70-turbine project.
A massive landslide occurred at Derrybrien in October 2003 when tonnes of peat was dislodged and polluted the Owendalulleegh river, resulting in the death of 50,000 fish.
After the the 2008 judgment, Ireland introduced a regularisation procedure to enable the operator of the wind farm to comply with the directive.
"Notwithstanding the legislative reform introducing a regularisation procedure, Ireland had failed to carry out a new environmental impact assessment of the wind farm, thereby failing to have regard to the authority attached to the 2008 judgment," a court statement said.
Lobby group Environmental Pillar welcomed the court's decision.
Spokeswoman Karen Ciesielski said it highlights "the catastrophic failure by our Government to adhere to environmental law".
"It has been almost 15 years since the ecologically devastating landslide of October 2003, which could have been avoided if a proper assessment had been undertaken.
"We hope that the fines will act as a big wake-up call for our Government.
"However, any fines are just the tip of the iceberg when it comes to expenses incurred by the Irish people for environmental damage in our country.
"Damage is being done to our natural resources on a daily basis and there will be huge long-term economic costs in trying to fix the problems."
