A group representing about 190 landowners affected by the planned North-South electricity interconnector has been given permission by the High Court to challenge An Bord Pleanála's permission for the project.
The case is against the board; the Minister for Communications, Energy and Natural Resources and the State, with Eirgrid plc as a notice party.
Eirgrid has described the planned interconnector as a critical piece of national infrastructure.
The challenge is being mounted by the North East Pylon Pressure Campaign Ltd, from Navan in Co Meath, and Maura Sheehy, a farmer from Teltown Road, Donaghpatrick, Co Meath.
Ms Sheehy said in a sworn document that Donaghpatrick has been home to her sister and herself for some 75 years and they have a small landholding.
She has "grave concerns" about pylons near her home and feared this "obtrusive" development would destroy "not only my life but the life of my community and the simple rural landscape".
The case is the third initiated in the High Court over the interconnector, due to run from Batterstown in Meath, to Turleenan in Co Tyrone.
Earlier this month, David Malone, of Eurolaw Environmental Consultants, St Joseph Terrace, Portarlington, got leave to bring separate proceedings.
A decision on whether to grant leave to another man to bring a third, also separate, case, was adjourned on Monday for two weeks.
All three cases concern the decision by the Board on 19 December 2016, following a 12-day oral hearing, to grant EirGrid permission, subject to various conditions, to construct almost 300 pylons in counties Meath, Cavan and Monaghan.
Separate applications concerning those parts of the development located in Northern Ireland have yet to be decided and an oral hearing concerning those is due to resume in Armagh city on Wednesday.
Seeking leave on Monday for judicial review on behalf of the NEPPC and Ms Sheehy, Conleth Bradley SC said the case raises issues of administrative, constitutional and EU law.
He said the Board failed in its approval decision to properly address the impact on the rights of the affected landowners of erecting 300 pylons, including on the health of particular landowners.
The Board also failed to properly consider putting the development, or part of it, underground and the approval fails to meet requirements of the Planning Acts and EU directives concerning habitats and environmental impact, Mr Bradley added.
There are also issues over the status of Eirgrid to make the application and the relationship between it and ESB Networks, the court heard.
Mr Bradley argued the Board's decision fails to properly address the European regulation concerning Projects of Common Interest (PCI) and the Brexit impact concerning this project for a single electricity market.
While the Board referred to the project likely to have a significant impact on Northern Ireland, described in the Board decision as part of an EU member state, the decision failed to properly consider the consequences of UK withdrawal from the EU, he argued.
While his side anticipated the Board might respond to the claims relating to Brexit by arguing the project could be split, his side contended it cannot, counsel said.
Mr Justice Seamus Noonan granted leave for judicial review on the grounds advanced and returned the matter to 25 April.
He granted a stay on implementation of the conditions of the permission but gave liberty to the respondents and notice parties to apply if they wished to vary the terms of the stay.