The High Court has reserved judgment on the issue of whether it has jurisdiction to decide if the THORP nuclear reprocessing plant at Sellafield should have been subject to an Environmental Impact Assessment (EIA) in line with EU directives.
Four Dundalk-based residents, who have been pursuing a challenge to the Sellafield plant in the Irish courts since 1994, claim Britain failed to observe EU directives in relation to the reprocessing plant and want an order from the High Court directing British Nuclear Fuels plc (BNFL) to comply with those directives.
Mr Justice Peart has been asked to decide the extent of the Irish court's jurisdiction in the matter.
The three-day hearing concluded yesterday and judgment was reserved.
BNFL claims the Irish courts cannot pronounce or invalidate the regulatory procedures adopted and fulfilled by the sovereign bodies of another EU member-state.
The four persons taking the action against BNFL are Ms Constance Short, Ms Mary Kavanagh, Mr Mark Deery and Mr Ollan Herr.
They have also taken proceedings against Ireland and the Attorney General alleging the State failed to take action, including legal action, to prevent the nuclear reprocessing plant coming into operation.