Donegal County Council says a full multi-agency investigation is underway into the bog slippage at the site of Meenbog Wind Farm near Barnesmore Gap, with a focus on mitigating the impact of the event, preventing further pollution, and determining the cause of the event.
No threat has been identified to water supplies on either side of the border, but there is serious concern for the future of the salmon and trout fishery in the Derg River system in Tyrone.
Local campaigners say they have been warning something like this would happen for some time.
Meanwhile, a Donegal TD is calling for changes in the way Environmental Impact Studies are carried out on proposed infrastructural developments such as windfarms.
On the Nine til Noon Show today, Deputy Thomas Pringle said there is one change that could be made now which he believes would improve confidence in the system......