The Government is being taken to court by the European Commission over a range of health and environmental issues, including failing to deal with noxious odours from some of the country's sewage-treatment plants.
Under EU rules on waste management, member states have to make sure waste plants do not give off unpleasant smells.
The commission said today it was taking legal action in the European Court of Justice following complaints about the smells coming from a number of Irish treatment plants, including the country's largest, in Ringsend in Dublin.
"Legislation promised by the Irish Government to better regulate the management of such plants has not yet materialised," said a commission statement.
The legal case will also attack what the commission says is a lack of satisfactory rules and controls to ensure that the siting, design and maintenance of domestic waste water treatment systems do not damage the environment.
"Many Irish water supplies are contaminated by bacteria, the principal causes of which are land-spreading of animal wastes and leaking domestic waste-water treatment systems," the statement continued.
"Ireland is attempting to deal with the public health risk by devoting EU and Irish taxpayer resources to investment in chlorination and other forms of disinfection of contaminated water sources. However, more needs to be done to protect the sources from becoming polluted in the first place."
A second commission court case against Ireland is over the alleged failure to carry out environmental impact assessments of various projects, as required under EU environment laws.
Today's statement highlighted the case of Ireland's largest wind farm project at Derrybrien, Co Galway. Initial work on the project led to an environmental disaster in October 2003, the commission said, with half a million cubic metres of peat displaced in a landslide that damaged property and killed about 50,000 fish.
An environmental impact assessment had failed to properly assess the risks the project presented because of soil instability, the commission complains - and so far the Irish authorities have failed to give any commitment to carry out a fresh environmental impact assessment before work on the project resumes.
In a third legal action, the commission is sending the Irish Government a written warning for failing to comply with a European Court judgment last October in which the judges condemned Ireland for failing to provide reports on measures it is supposed to be taking under EU law to protect the ozone layer.
Ireland is the only EU member state that has not provided the necessary information, due to have been received by the commission at the end of 2001.
If today's written warning does not produce results, the commission can impose a hefty fine for continuing to ignore last October's ruling.