Hundreds of people in Baltinglass, Co Wicklow, are still without running water today after high levels of uranium were found in the local supply.
The water supply was cut off yesterday on the recommendation of a nationwide testing programme which found high levels of uranium in a well that supplies parts of the town.
Opposition politicians are expected to raise the matter in the Dail today.
Fine Gael has called on the ministers for the environment and health to clarify the significance of the contamination, while the Labour Party said the discovery raises serious questions about the management of water supplies in west Wicklow.