DUBLIN City Council want the High Court to halt a challenge to €270m works extending the capacity of the Ringsend waste water treatment plant.
Mr Justice Peter Charleton has reserved judgment on the council's pre-trial application.
The Sandymount and Merrion Residents Association (SAMRA) initiated the challenge last month due to concerns about the environmental impact of the project which will include a 9km underground tunnel under the sea to discharge treated effluent into Dublin Bay.
The residents want orders overturning the An Bord Pleanala (ABP) permission last November for the works. That permission was granted just weeks before the Minister for Arts & Heritage proposed on December 3 to designate a 40km coastal stretch from Rockabil, Howth, to Dalkey Island as a special area of conservation (SAC).
In affidavits for SAMRA, local resident Lorna Kelly claimed the underground tunnel will discharge treated effluent into an area directly within, or adjacent to, a SAC.
She also alleged an Environmental Impact Statement (EIS) provided for the development was inadequate.
The case is against ABP and the State with the Council a notice party.
The Council and State applied to the Commercial Court earlier this month to fast-track the action, arguing it was urgent as the Ringsend plant is operating above designated capacity.
The State has told the EU Commission the plant would fully comply with the Urban Water Treatment Works Directive by next May and it will be exposed to fines if compliance was not achieved, it was stated.
The Council said the Ringsend plant was built in 2003 to cater for a population of 1.64m in the greater Dublin region but is now trying to cope with average daily influent of 1.8m. The planned extension will provide capacity for 2.1m.
James Connolly SC, for the Council, supported by counsel for the State, Brian Kennedy, applied for the challenge to be struck out on grounds SAMRA, as an unincorporated entity, is not entitled to bring it. An unincorporated body is a "legal nonentity" not answerable to the court for costs or other matters such as contempt, he said.
He said the residents need not be concerned about discharge of treated effluent into the proposed SAC as both an EPA licence and foreshore licence would be required before that could happen, adding further layers of statutory control on top of planning conditions . Treated effluent is already being discharged into other areas of Dublin Bay but under proper controls, he said.
The Minister's proposed designation of the Rockabil-Dalkey island coastal stretch as a SAC could not invalidate the planning permission, he argued. An extra layer of statutory control under the Habitats Directive would protect the environment, he added.
Niall Handy BL, for SAMRA, said it was actively involved in the planning process concerning the Ringsend plant from the outset and entitled to seek judicial review.
This was not a NIMBY (Not in My Back Yard) argument as there were much wider issues at stake affecting all of Dublin Bay, he said.
SAMRA had the necessary sufficient interest in this matter entitling it to bring the case, there was nothing in Irish law to prevent it doing so and it was not required to form a limited liability company to bring such a case.
Mr Handy argued the Habitats Directive required a more stringent EIS than was provided for this project. Material obtained following a Freedom of Information request had shown the proposed designation of the Rockabil-Dalkey Island was under consideration before planning permission was granted, he added.