The delicate process required for the safe removal of peat from blanket bog was outlined by local people at the oral hearing in Ballina into the proposed Corrib gas terminal at Bellanaboy Bridge, north Mayo, yesterday.
In a number of submissions, local people repeatedly expressed concerns that the planned removal by the developer, Enterprise Energy Ireland (EEI), of 660,000 cubic metres of peat from 37 acres of blanket bog in the area, which is to be placed on top of existing sloping bog at two nearby peat repositories in the terminal site, could result in disastrous and unpredictable consequences. These could include contamination of the groundwater supply from both the excavated and repository peat, damage to the environment in four surrounding sensitive areas owing to infiltration of bog water constituents and a peat slide within the manipulated peat zone.
An iron pan layer, deemed to be impermeable by EEI, was also said to be localised, rather than uniform throughout.
A peer review on the stability of the peat was also criticised for having been carried out by EEI rather than independently.
One local man, Mr Séamus Healy, who worked for over a decade with Coillte and who had first hand experience of installing drainage pipes in the bog, described how the bog could often behave like jelly. Timing was a crucial factor in the digging of drains, he said, to prevent peat collapse and water run-off. It often took years to install just one pipe as only minimum levels of bog could safely be sheared off each year, he said.
Mr David Ball, for An Bord Pleanála, assessing groundwater flow within the bog, said the developers intended to lay a mat on top of the bog and then apply material for the haulage roads. He asked was that good.
Mr Healy replied there would still be an issue in relation to water drainage.
Mr James Healy, another local man, pinpointed a location in the vicinity of the site where a number of diseased rabbit carcasses from a local animal research station had been buried.
Mr Martin Healy, former Bord na Móna employee of 23 years, suggested that if a disaster did not occur during excavation, it would only be a matter of time before the peat repositories failed.
"The works proposed here are far more complicated than any of Bord na Móna's activities I have been involved in. I think EEI would find it very difficult to operate machinery there without getting stuck and having to be pulled out by other machines. Once the ground is disturbed in that way, it becomes unstable," he said.
Mr Eamon Galligan SC, for EEI, said expert witnesses had already given assurances that water systems would not suffer as a result of excavations.
Mr Turlough Johnson, engineer, concluded that thorough stability analyses demonstrated that the design safety standards were adequate. Mr Cecil Shine, hydrogeologist, said the proposed management of waters by EEI would actually lead to an improvement in water quality in time. "Everything leaks to some extent, even the floor we are on now," he added.
Mr Galligan said he wanted to clarify points raised as to whether the gas in the terminal was wet or dry. "Corrib gas is very dry; however, a certain amount of water will process out and the Department of the Marine is fully aware of this," he said.
The hearing continues.