A High Court judge has said it would be undesirable to see a race between the diggers and the courts over the Carrickmines Castle site.
Mr Justice Michael Peart has requested affidavits from Dún Laoghaire/Rathdown County Council and conservationists at the site giving details of the work that has taken place there since Monday.
Conservationists have sought an injunction stopping the work as soon as possible.
They are challenging the constitutionality of the legislation passed last month allowing the motorway to go ahead despite the presence of the historic monument.
Conservationists claim that work being carried out by the county council since Monday is illegal and they maintain a large bulk of the monument could be demolished or removed by next week.
Counsel for Dún Laoghaire/Rathdown County Council said the work that had been taking place did not involve any demolition but mainly archaeological excavation which had been undertaken in an orderly fashion.
Both sides will present their affidavits tomorrow morning.
A full hearing of the constitutionality of the legislation allowing the motorway to go ahead is expected to take place next week.
