The company behind Ireland's first goldmine faces a roadblock over plans to keep its operations going for the next 15 years.
Galantas Gold Corporation has flagged up a possible challenge to its plans for an extension to the mine at Cavanacaw near Omagh.
The proposal was approved by Environment Minister Mark H Durkan in June this year, but with strict environmental conditions.
Last week the company said it had become aware of an individual who intends to apply for a judicial review into the actions of the Department of the Environment when it gave planning permission.
If proposals for the mining of gold, silver and lead go ahead, it would mean a further 15 years of work at the existing mine.
Another minerals firm, Dalradian Gold, says Northern Ireland has the seventh richest undeveloped seam of gold in the world.
Galantas's chief executive Roland Phelps said he is confident that the court will uphold planning approval.
"The individual challenging the decision raised concerns during the planning process and I note that these concerns were carefully examined by Department of Environment Northern Ireland Planning Service," he said.
"The company will be seeking additional information and will advise shareholders of material information if it arises."
The company expects to invest £17m-£20m in the project. The plans would allow underground works in the existing mine site to extend to a length of 600 metres and up to a depth of 350 metres. It would include progressive restoration of the above ground site to ensure the protection and enhancement of habitat over time, Mr Durkan said in June.
"The proposed operation by Omagh Minerals (a subsidiary of Galantas) should help create numerous jobs and secure existing ones at the site. These and the wider benefits the development will bring will help the local economy. Environmental protection will be of paramount importance. The company will be operating within strict compliance parameters. This combination will help achieve my vision of a stronger economy, a better environment."
Galantas has said it anticipates 130 people will be working on the mine with total wages of £4m when it is fully operational.
In 2012, the NI Ombudsman told the Planning Service to pay a total of £30,000 compensation to three residents for failing to enforce planning regulations at the mine.
In 2008 and 2009, Omagh Minerals allowed hundreds of thousands of tonnes of rock to be removed by truck along a narrow road network without the necessary planning consent.
Despite several objections, it took the Planning Service over a year to issue an enforcement notice telling the company to stop.
According to Ombudsman Tom Frawley, the planners' failure to act represented maladministration in what he said was a "major system failure" at the Planning Service.