Indian conglomerate the Adani Group's plan for the largest coal mine in the Australian state of Queensland is moving forward with an environmental review process.

If approved, the Carmichael Coal Project in the Galilee Basin, the last undeveloped coal resource in Queensland, would extract 60 million tons of coal each year from an open-cut and underground mine for export to India.

No timeline was given for the environmental impact study, released by the Queensland government.

Critics of the Carmichael project include the Capricorn Conservation Council, which said it is particularly concerned about the impact of mining discharge on the environment, and agricultural lobby group AgForce which says food security could be jeopardized if agricultural land is overtaken by mining.

Adani recently finalized purchase of the site from a cattle station for $110 million, the International Business Times reports. In all, Adani is expected to spend at least $6 billion on the project.

Considered the largest investment by an Indian company in Australia, Adani's investment for infrastructure and mine development includes a $3.1 billion railway network to haul the coal to two ports, one purchased last year and another yet to be built.

From there, company-owned bulk carriers would then ship the coal to India.

Queensland Mining Minister Stirling Hinchliffe said the project initially would employ 5,000 workers for the construction phase, later resulting in 4,000 permanent jobs.

"I think it's important that … the largest number of jobs are taken up by Queenslanders," Hinchliffe told the Australian Broadcasting Corp. "But there will be some particular areas, and some very particular skills, that will be required to be brought in from overseas."

The Queensland Resources Council in its November 2011 Growth Outlook Study said the state's growing resource sector would need more than 40,000 more workers in the next eight years, which couldn't be met by the local labor market.

But Adani says it plans to hire Australians for the Carmichael project before hiring overseas workers.

The company plans to build a town in Queensland to house workers as well as an on-site airstrip for a fly-in, fly-out workforce, ABC reports.

Exports from the Carmichael project, intended to supply seven Indian power stations operated by Adani Power, are expected to start in 2015.

Although India has the fifth-largest coal reserves in the world, much of it lies under forests in areas populated by tribal groups and proposed projects are typically met with protests.

Coal accounts for approximately 67 percent of total energy in India.