The decision – which has been widely anticipated by Whitehaven Coal, Idemitsu and local environmentalists – will ultimately determine how far the coal-rich Gunnedah Basin will be developed.

“The federal Environment Department is currently assessing the Maules Creek and Boggabri coal mining projects for impacts on matters protected under national environmental law including listed endangered and migratory species and critically endangered ecological community,” a spokesperson for Bourke told ILN.

“The assessment and approval process set out under national environmental law is open and thorough, taking into account scientific advice and public comments.

“Once the assessment process is complete, Minister Burke will carefully consider the assessment, the advice of the department and all public comments received before deciding whether the proposal can go ahead.”

Earlier this month a hoax announcement stating the ANZ bank was withdrawing $1.2 billion in credit for the Maules Creek project was organised by environmentalists to derail federal government approval for the mine and hinder further developments in the Gunnedah Basin.

The extreme actions of anti-coal campaigner Jonathan Moylan and the Front Line Action on Coal group typify the lengths some individuals and groups will go to put their case on the national agenda.

The publicity drew national attention to the 10.8 million tonne per annum project and was planned to put pressure on Burke to knock back the application.

Environmental groups and farmers in the Gunnedah Basin formed an alliance with Lock the Gate to prevent Maules Creek being federally approved after the NSW Planning Assessment Commission gave the project the green light in October.

The alliance claims Maules Creek, the Tarrawonga joint venture and the neighbouring Idemitsu-owned Boggabri mine will produce up to 23Mtpa of coal and impinge on the nearby Leard state forest, koala populations and surrounding agricultural land.

Leard State Forest is the largest remnant left on the heavily cleared Liverpool Plains.

It provides habitat for up to 34 threatened species including the koala, environmentalists say.

More than half of the entire state forest, close to 5000 hectares in total, will be cleared by the three mines.