The High Court has ruled against the constitutional challenge to the south Dublin portion of the South Eastern Motorway at Carrickmines Castle taken by Dublin conservationist Mr Dominic Dunne.
Ms Justice Laffoy delivered a 60-page ruling against the three arguments presented by the plaintiff at the High Court in Dublin and said she could not accede to either application, clearing the way for the work to continue.
Legal submissions ended last Tuesday. Mr Dunne claimed part of the National Monuments Amendment Act, 2004, was unconstitutional and contrary to EU directives.
Section 8 of the Act, which was introduced earlier this summer, allowed for the partial demolition and removal of the ruins of Carrickmines Castle to allow for the construction of the South Eastern Motorway - the final link in Dublin's M50 bypass.
Dún Laoghaire-Rathdown County Council was ordered to stop work on the controversial M50 route on August 19th to facilitate a full High Court hearing into the legality of the new heritage legislation.
The Council said this evening that work will now resume on the site tomorrow morning.
Justice Laffoy said she could not agree with any of the arguments presented by Mr Dunne during the four-day hearing last month.
She ruled that Section 8 of the National Monuments Amendment Act was not unconstitutional and that the works did not need a new environmental impact study under EU law to go ahead.
Lawyers for Dunne said they wanted to study the judgment before deciding whether to appeal to the Supreme Court. Mr Dunne's Counsel, Mr Colm Mac Eochaidh, was granted an adjournment on costs until October 19.
Outside the court, Dun Laoghaire-Rathdown Co Council hailed the victory and said work would resume at the Carrickmines site tomorrow morning.
Senior engineer John McDaid said: "We are delighted. Everything was in our favour."
He claimed that delays in the South Eastern Motorway project, which was halted by court order on August 19, had cost the taxpayer up to €357,000 per week.
Conservationists have accused the National Roads Authority and the council of exaggerating the costs of the delays brought about by the various court cases.
Mr Dunne admitted he was disappointed with the decision but insisted the action was never taken to block the M50 motorway but as a protest against the Government's "anti-heritage legislation".
His spokesman added: "Many of us are close to financial ruin because of these court actions. But we feel good about what we have done and we feel the Irish people will understand."
The project was previously dogged for two years by sit-in protests and legal battles. The motorway was to open to the public by October 2004 but that date has now been extended to August 2005.