Dun Laoghaire-Rathdown County Council and the National Roads Authority have insisted a 1983 archaeological report on Carrickmines was "taken into account and adhered to" in designing the final phase of the M50.
They said yesterday the report, prepared for An Foras Forbartha, had forecast little interference with archaeological remains in two areas near Carrickmines Castle. The Glenamuck Link Road occupies one of these areas and the South Eastern Motorway occupies the other.
Mr Eamonn O'Hare, the council's director of transportation, said the motorway planning was carried out in full accordance with statutory procedures. "All relevant reports were studied and it is mischievous to suggest otherwise," he said.
Excavations over a two-year period at the Carrickmines site, costing €6 million, revealed some of the defensive elements of the castle and associated industrial and habitation areas. The physical remains of the castle itself were not found.
In response to public protest, significant elements of the castle defences are to be preserved by Dún Laoghaire-Rathdown County Council and the NRA.
