The controversial Narrabri Gas Project has been approved this morning, subject to more than 100 conditions.
The $3.6 billion plan to sink as many as 850 coal seam gas wells in and around the Pilliga State Forest west of Narrabri was given conditional approval by the Independent Planning Commission (IPC) on Wednesday morning.
The project has attracted both fierce opposition and support for more than 15 years since Eastern Star Gas struck the mineral in 2000.
The IPC heard largely opposition to the project during its record seven-day public hearing, and thousands of submissions.
But the IPC signed off on the scheme after commissioners spent six weeks considering the project. They imposed 134 conditions on gas development.
In its statement of reasons for the decision, the Commission "is satisfied" that a potential threat to groundwater from the project "can be effectively managed under the conditions of consent".
Groundwater modeling performed by proponent Santos "was considered fit for purpose for this approval" the IPC said in its statement. But the company will be required to improve their modeling over time.
The Commission also rejected an argument that the project would unacceptably contribute to climate change through fugitive emissions.
Santos will be required to measure and minimise emissions at the project, and "fully offset" any emissions in excess of their budgeted amount.
Commissioners also rejected concerns about bushfire risk, Aboriginal heritage, social and health effects, biodiversity and waste management.
"The Commission considered the likely economic impacts of the Project and is satisfied that on balance the Project will provide a net economic benefit for the local community, region and state through increased investment and economic activity," the statement of reasons said.
Local MP Roy Butler, who opposes the project, said this week that government pressure has created "question marks around approval".
"I think the key thing here is perception," he said.
"You can have the most independent group in the world who has every check and balance to make sure that they are independent.
"But if the public believe their independence has been compromised that's the what's they're going to believe and that's the lens they will look at the world."
Supportive Narrabri Mayor Ron Campbell, who took over from former mayor Cathy Redding just last week, said approval is "simply a matter of law" and is "not a popularity contest".
Politicians from both Commonwealth and state governments talked up the prospect of a 'gas-fired recovery' in recent weeks.
No other coal seam gas project nearing approval stage could fill a shortage business and political leaders have long warned could threaten local industry.
Santos has committed to start construction of the project "shortly" after it is approved.