A five-week court case objecting to a $16.5 billion coal mine in the Galilee Basin is set to begin in Queensland's Land Court.

Lobby group Coast and Country says litigation is its last resort to stop Indian giant Adani’s plans to extract up to 100 million tonnes of coal a year from the Carmichael mine.  The company last year won state government approval to construct a 300km rail line linking the mine with the Abbot Point coal terminal, north of Bowen.

Those opposed to the project argue it will threaten the local ground and surface water supplies, the Great Barrier Reef, the Queensland economy and the world’s climate.  It was also given special treatment by the former Newman government with royalty breaks, according to Coast and Country spokesman Derec Davies.

“They (the former government) took at face value the misleading claims about the extent to which Queensland will benefit,” he said.

“Part of our case is that Queensland will not benefit from this mine.”

The group has also raised questions about the company’s inability to finance the project.

The mine, which would be the third biggest coal mine in the world, has also stirred tensions with traditional owners the Wangan and Jagalingou people (W&J).

Last week a W&J spokesman, Adrian Burragubba, announced they had rejected an indigenous land use agreement associated with the project.

In return, Adani rejected Mr Burragubba’s statements saying he was not an authorised spokesman for the group.

The company had been working closely with the W&J since late 2011 under a cultural heritage management plan, a spokesman said.

Over the next month, the legal challenge to the project will expected to hear from environmental, indigenous, groundwater, climate, finance and economic experts.