STOP Adani protesters gathered outside the mining company's Brisbane headquarters this morning calling for the Great Barrier Reef to be protected.
Grandmother Mary Turnbull was among about 200 people who turned up for the "snap rally".
She said she believed Adani's negative impacts would outweigh any value to the state from job creation.
"I can't believe the stupidity if it wrecks the coral reef which is worth $40 billion to the Australian economy," she said.
She said did not believe Adani chair Gautam Adani had Australia's long-term interests at heart.
"He can take his couple of billion dollars and he's off."
She said she was at the protest because she had seven grandchildren and wanted them to grow up in a world with a decent environment.
Protesters showed placards calling for the reef to be protected and objecting to taxpayer subsidies for the mining company.
The Stop Adani Brisbane campaign rally was outside Adani HQ in Brisbane to raise awareness for their cause before an impending election and before work is set to begin on the Adani mine.
Seed Indigenous Youth Climate Network national co-director Larissa Baldwin said Adani had said it would begin construction on its railway line within days "even before they have finance for their project".
"We know that nearly eight out of 10 Australians (77%) who have heard of Adani are opposed to the coal mine going ahead. These are truly terrible numbers for Adani, and any political leader, candidate or financial institution looking to back Adani should take heed," Ms Baldwin said.
Millie Anthony, from the Australian Youth Climate Coalition, said Queenslanders deserved better from their leaders.
"It's scandalous to hear that the state government has just moved to compulsorily acquire land from Central Queensland graziers for Adani's railway line, in what may be one of their final acts before placing the government into caretaker mode," she said.
In August, Whitsunday Residents Against Dumping lost a court battle over Adani's Abbot Point Terminal expansion. WRAD was told to pay Adani's court costs.
The coal terminal's expansion project was part of the $21 billion Carmichael mine, port and rail development.
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