Leaked documents and video suggest Adani is planning a bigger mine and wants to combine with other miners to export up to 100 million tonnes (MT) of coal a year from Queensland's Galilee Basin.

Key points: Adani Australia chief executive Lucas Dow appears concerned an audience member was recording his remarks

Adani Australia chief executive Lucas Dow appears concerned an audience member was recording his remarks Sodexo told its employees "not to actually mention the name Adani" when referring to its construction contract

Sodexo told its employees "not to actually mention the name Adani" when referring to its construction contract AEC returns show Adani subsidiaries donated $247,300 to the Liberal and National parties in 2018/19

In November 2018 the Indian mining giant announced a "scaled down" 10MT-a-year mine, eventually increasing to 27MT — far less than its original 60MT plan.

A 2019 contract, obtained by the ABC, showed Adani was preparing to build a mine rail link that would start hauling 40MT-a-year but with an "ultimate capacity" of 100MT, assuming other mines went ahead in the basin.

In July last year, Adani Australia chief executive Lucas Dow was recorded speaking at an LNP fundraiser on the Gold Coast where he emphasised Adani was permitted to export up to 60MT.

In the video, obtained by the ABC, an attendee asked Mr Dow how many jobs a 10MT-a-year mine would deliver, Mr Dow replied: "Well, that's the initial phase."

"The one thing we've been very clear on is we're permitted up to 60MT," he said.

In the video, Mr Dow then appeared concerned an audience member was recording his remarks.

"Sorry, are you recording that? Or you're … no? Okay. We're permitted up to 60 million tonnes, so the reality is we've got an opportunity to be able to expand beyond that," Mr Dow said.

In the video, Mr Dow appeared concerned an audience member was recording his remarks. ( ABC News: Jessica Rendall )

'Keeping it very hush, hush'

The plan to haul up to 100MT a year of Galilee coal by rail is contained in Adani's September 2019 contract for construction camp operations with French mining services giant Sodexo.

Burning 100MT of coal for electricity would emit between 188MT and 243MT a year — more than the entire state of Queensland (158MT) — according to the Climate Council.

Chris, a Sodexo employee who asked not to be identified, told the ABC he leaked the contract to activists because "from a personal point of view, I don't particularly agree with our servicing that contract".

"They have been keeping it very 'hush, hush' that we will be providing the services to Adani on their sites in Queensland. Information has been released on a need-to-know basis," he said.

He said Sodexo had told employees "not to actually mention the name Adani" when referring to the contract.

The workers camp at Adani's Carmichael coal mine. ( ABC Rural: Amy McCosker )

He said at a meeting last month, employees were told that "we'd be getting extra security installed on all of our offices around the country and that we are not to speak to the media and that we're not to speak to protesters".

"They've managed to keep it so quiet so far and I think that's obviously a deliberate effort … to try and avoid some of the inevitable attention that they'll get and they rightly deserve," he said.

Chris said Sodexo was "very big on corporate responsibility and sustainability", having won awards including a top ranking in its sector in the Dow Jones sustainability index.

"I find that quite hypocritical that we always spruik the good work that we do on corporate responsibility but then on the other hand, we support projects like this one," he said.

A mining camp for Adani Australia as it builds the Carmichael mine. ( Twitter: Adani Australia )

An Adani spokeswoman said, "The Carmichael Project was redesigned in 2018 to be a 10MT-per-annum mine".

"We are building a 10-million-tonne-per-annum mine and, as per our original approvals, have permits in place for a 60-million-tonne-per-annum operation," she said.

"The Carmichael Rail Network will be a multi-user rail line ensuring other mines in the Galilee Basin have access to transport infrastructure.

"The Carmichael Rail Network comprises a 200km narrow gauge rail line, connecting to existing rail infrastructure.

"Initial capacity is 40MT per annum, with the opportunity for increased capacity through the development of passing loops on the network if required."

A Sodexo spokeswoman said, "For commercial and competitive reasons our standard business practice is to not discuss the individual companies we may or may not work with".

"The safety and security of our employees is paramount at all sites and locations where we operate."

The Sodexo contract stated there would be three construction camps for Adani's 200km-rail link, housing up to 1,029 workers.

Adani donated $247k to LNP

Australian Conservation Foundation (ACF) spokesman Christian Slattery said Adani had been "caught saying one thing to the public and in this case, another thing to their political mates in the Queensland Liberal National Party".

"They've been saying for the last two years that this would just be a 10MT mine or a 27MT mine in stage two," Mr Slattery said.

"But what this document clearly shows is that Adani intend to build up to their permitted volume and open the way to many more mega mines in the Galilee Basin."

Lucas Dow at the mine site in March 2019. ( ABC Rural: Amy McCosker )

Last year, when Adani's groundwater plans were reviewed by CSIRO and Geoscience Australia, the miner refused to commit to "a scaled-down mine plan".

Adani is the most advanced of the prospective Galilee Basin miners and faces an uncertain wait for others to follow.

Prospective mines linked to billionaires Gina Rinehart and Clive Palmer face more regulatory and financial hurdles, while the China Stone project's China-based owners last year abandoned their bid for a mining lease.

Adani's Carmichael coal mine site in December 2018. ( Twitter: Matthew Canavan )

Adani channelled almost a quarter of a million dollars in political donations to the Liberal and National parties last financial year.

This year activists targeting Adani contractors forced the bus company Greyhound to move to cut ties with the miner, but the German company Siemens stood by a rail signalling contract for the Carmichael project.