Dún Laoghaire-Rathdown County Council need not prepare a revised environmental impact statement (EIS) for modifications to the Carrickmines interchange of the M50/South Eastern Motorway.
An Bord Pleanála has ruled that the modifications to the design of the interchange "do not significantly alter" the road scheme from what was previously approved and that it "remains in essence the same".
Ruling on a reference case brought by Mr Stephen Devaney, a barrister, the board said the modified version of the interchange would not of itself have significant adverse effects on the environment.
In reaching its decision, the planning appeals board had regard to the previous approval by the then minister for the environment, Mr Dempsey, in October 1998 of the county council's plan and the extent of the modifications made to the design.
These were the changes to the scheme made last September on foot of an intervention by the Minister for Transport, Mr Brennan, in response to a high-profile campaign by a group of environmentalists and conservationists for the preservation of Carrickmines Castle.
Last month, the Supreme Court ruled that Dún Laoghaire-Rathdown County Council would have to seek consent under the National Monuments Acts for the removal of archaeological remains on the site.
It is understood the county council has since agreed to seek the necessary consent, which may involve laying the matter before the Houses of the Oireachtas on the basis that it is in the public interest.
It is also believed that the newly-formed Friends of Carrickmines group has put forward compromise proposals which would involve covering over, rather than removing, a medieval fosse (stone ditch) on the site.
