In High Court proceedings, a number of local residents want the Bord's decision quashed.
A legal challenge taken against An Bord Pleanala's decision to approve a proposed road development near Kilkenny City has been referred to the Courts of Justice of the European Union.
Mr Justice Richard Humphreys said he was referring the case to the Luxembourg based CJEU for clarification of certain aspects of European Directives concerning the conservation of natural habitats and of flora and fauna.
The case concerns a development, known as the Kilkenny Northern Ring Road Extension, which the Board gave Kilkenny County Council permission to construct a 1.5km section of road in July 2014. It is part of an overall project designed to improve transport links and keep HGV vehicles out of the centre of the Medieval city.
The proposed road, which is a small part of an overall ring road around Kilkenny, cuts through a number of protected natural areas, including a special protection area for wild birds to protect the kingfisher. It also impacts on proposed national heritage area and a candidate special area of conservation which is the only site in the world where the Nore freshwater pearl mussel exists.
In High Court proceedings, a number of local residents want the decision quashed.
The action, which has been opposed by the board, has been brought on grounds including that the council failed to consider the environmental effects of alternative options to the proposed road and that an appropriate assessment of the project conducted by the local authority was deficient.
The council and the Minister for Arts, Heritage, Gaeltacht, Regional and Rural Affairs were notice parties to the proceedings.
In a written judgment Mr Justice Humphreys said in this case it was appropriate and necessary that eleven questions of law relating to EU directives concerning the conservation of wild fauna and flora be referred for clarification to the CJEU.
The questions include if statements, concerning the impact a proposed developments may have, identify the entire extent of the habitat and species on that particular site. In addition under the CJEU have been asked to determine a question concerning assessments of the impact a proposed development will have on protected species and habitats both inside and outside special areas of conservation.
A further question is if, under an EU Directive, an environmental impact assessment on a proposed development should contain sufficient information about the environmental effect of each alternative to the proposal. The information about the alternative option would enable a comparison to be made between the environmental desirability of the different options.