Yancoal, the owner of the Ashton coal mine in the Hunter Valley, is calling on the state government to approve the installation of more gas wells to vent methane from the underground mine.
The New South Wales mine is located near the Blakefield South coal mine, where a fire caused by a methane explosion saw 55 men evacuated from the underground mine.
Last year Yancoal installed three gas draining wells at the Ashton mine, and has requested an additional 15 wells be build on the surface.
Pre-development geological investigations reports show coal sea, gas would not hinder the underground operations at shallower levels, but higher gas levels than expected have been reported.
The wells will exhaust up to 328 000 tonnes of carbon dioxide annually, which will initially be vented directly into the atmosphere until better drainage networks can be designed and build for future operations.
The community consultation committee for the mine has been told drilling could take up to two years to complete.
Ashton coal is still waiting on development consent from the Department of Planning and Infrastructure for an extension to increase its production by and extra 100 000 tonnes of coal per year, following a delay in government approval for the 2009 application.
Now owned by Yancoal, the application requested permission for the company to develop the South-East Open Cut, near its Camberwall operations.