Northern Ireland's Minister of Environment has granted planning consent for expansion of Galantas Gold's underground gold mine at the Omagh site.
The consent includes operating and environmental conditions, which will clear way for the company to expand activities at the mine, which is currently under suspension.
Galantas Gold plans to extend underground mining at the existing site to a depth 350m and length of 600m.
The company will ensure progressive restoration of the above ground site, in order to protect and enhance landscape and habitat.
According to the company, recent economic study found good results at the Omagh gold mine that is expected to create hundreds of local jobs and provide a boost to Northern Ireland's economy.
Galantas Gold said that the decision came after three years of environmental examinations and other factors regarding the application.
As part of the examination, the Northern Ireland Environment Agency (NIEA) and independent specialists conducted environmental studies at the property, which has many un-drilled targets.
Galantas Gold president and CEO Roland Phelps said: "This is a significant milestone and a gamechanger for Galantas. Our open pit gold mine, operated until recently, is the only one in Ireland.
"It had excellent environmental standards, monitored with detailed studies by NIEA and used a safe processing methodology to produce a smelter concentrate."
Once the required finance is in place, the company aims to establish the underground mine and plans to further expand gold resources on the property.
Northern Ireland Environment Minister Mark H Durkan said: "This is a real boost in terms of jobs and investment for the Omagh area.
"The proposed operation by Omagh Minerals 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."