Indian conglomerate GVK's massive coal mine project in central Queensland, Australia, has been granted environmental approval.

The Kevin's Corner project, along with GVK's two Alpha coal projects, when combined, "will create one of the largest coal mining operations in the world," GVK said in a release following the approval Friday by Australian environment minister Greg Hunt.

The three projects, all in the coal-rich Galilee Basin, hold total resources of 8 billion tons, with a peak capacity of around 80 million tons a year.

The state of Queensland granted Kevin's Corner environmental approval in May. The two Alpha projects received state and federal environmental approvals last year.

GVK says Kevin's Corner has a mine life of at least 30 years and can produce up to 30 million tons per year of export quality thermal coal. Construction is slated for 2015, with the first coal mined in 2018.

Coal from the mines would be transported to the coast for shipping to export markets, mostly China and India.

Queensland now exports about 180 million tons of coking and thermal coal annually, says the Queensland Resources Council, or QRC.

"Our projects represent one of the most significant pieces of regional and economic development this state has seen for decades," said Sanjay Reddy, Vice Chairman, GVK Power and Infrastructure.

The approval comes amid high costs of production and falling coal prices. QRC in August said the state's coal sector was facing the "toughest operating environment in more than a decade."

GVK says the three projects will employ around 7,000 people during construction and around 20,000 people once operational.

Environmentalists argue that the projects' location in the Galilee Basin means it could have an impact on the health of the Great Barrier Reef.

The Kevin's Corner approval is subject to more than 70 conditions, The Guardian reports, some of which are aimed at protecting threatened species.

But Drew Hutton, president of anti-mining group Lock the Gate, says the group is "bitterly disappointed" about the approval. "We will certainly be reviewing our legal options on this," he told the newspaper.

The decision, Hutton said, "has stood the whole approval system on its head," noting that in the past, environmental impacts had to be submitted in advance for the approval process, "but now you get approval and then work out exactly what damage it'll do to the environment."

"We no longer have the precautionary principle in place in the whole approvals process," Hutton said.

But GVK's group managing director, Paul Mulder, told the Australian Broadcasting Corp. the project has gone through an "extremely rigorous process" of environmental assessments, at a cost of $25 million involving 250 independent environmental consultants.