Special Areas of Conservation (SACs) and Special Protection Areas (SPAs) are areas designated for protection under the EU Habitats and Birds Directive on the basis of scientific evidence which shows their importance in protecting specific habitats, birds and species. Ireland is required to designate an appropriate number of these habitats and has now transmitted its finalised list of SAC sites to the European Commission, with the list of SPAs to be finalised next year. Any changes to that list will be subject to rigorous scrutiny for their scientific merits by the Commission. I have no current proposals to designate the areas mentioned in the question.
Designation of land for natural heritage reasons does not preclude development taking place, as long as the ecological impacts of proposed development are assessed as not significant or, if they would be significant, certain procedures set out under Article 6 of the Habitats Directive are followed.