Approval was given for a new nursing home on the shores of Carlingford Lough without properly considering potential harm to surrounding conservation areas, the High Court has heard.
Counsel for activists claimed the development could impact on ancient oaks at Rostrevor Wood in Co Down.
Folk singer Colum Sands, who lives in the area, is fronting the challenge to Newry Mourne and Down District Council’s decision to grant planning permission for the 70-bed facility.
His barrister, Richard Honey, told the court: “Putting so much development so close to such important habitats and designation is at the heart of this case.
“That gives rise to legal and policy consequences which were not recognised by the developer and, indeed, were largely not recognised by the respondent council either.
“As a result, they have not done what was necessary to comply with their legal and policy duties.”
Mr Sands is taking the case on behalf of the group Rostrevor Action Respecting the Environment (RARE).
Proceedings centre on plans to build a nursing home at the location where a hotel once stood.
According to RARE it will be situated adjacent to Carlingford Lough and Rostrevor Wood – both of which have protected status and been designated as areas of special scientific interest.
The group fears construction work and an increase in traffic will put the forest’s ancient oak trees at risk.
Despite a planning official recommending the scheme be refused, the council decided to give the go-ahead last year.
It followed an independent assessment which found no risk to the forest.
But Mr Honey claimed the process was legally flawed.
Opening an application for judicial review listed for three days, he claimed a screening from 2009 should have been carried out again before a decision was reached.
The barrister also alleged the potential damage to ASSI (Area of Special Scientific Interest) aspects raised by environmentalists was not properly assessed.
“The decision made didn’t consider harm and didn’t consider mitigation in relation to those features,” he contended.
The case continues.