Former Greens leader Bob Brown wants Australia to morph into the world's biggest exporter of renewable energy and do away with the coal mining that he says will sting farmers and livelihoods if allowed to go on.
In Brisbane to address hundreds of protesters as part of a days-long demonstration against Indian mining firm Adani, Mr Brown said vital water and food resources would perish if it's coal mine went ahead.
"If we don't stop this the Murray Darling basin will be heading to 90 per cent loss of food productivity, and with that loss of farmers, loss of livelihood and loss of a feeling of wellbeing on the planet," he told reporters.
"We're here to ... be sensible, replace it with renewable energy, and you can't do that if we're exporting Adani coal into super heating this planet, which we've seen has resulted in worse floods in Townsville, worse fires in Tasmania, and round the world."
Mr Brown hit back at a report in the Courier Mail on Sunday that one of his supporters had posted remarks comparing workers to Nazis during the Holocaust in a private Facebook group.
The post read "There were jobs for locals in the gas chambers in Nazi Germany too. There is such things as a bad job."
Mr Brown says he told the reporter prior to publication that he absolutely repudiated such comments, and they had been taken down.
Greens leader Richard Di Natale said coal had no long term future and governments should instead focus on creating industries that gave people more job security.
"If we really care about people in coal communities we'd actually have a long term plan for sustainable jobs in renewable energy," he said.
Documents have revealed Adani did not accept expert scientific advice on how to limit the environmental impact of its proposed central Queensland coal mine.
The Queensland government must sign off on its management plans for groundwater and a rare finch before construction can begin.
Last week Deputy Premier Jackie Trad cited potential threats to the state's water resources if the mine was approved, but when pressed could not identify what the specific risks were.
"Our water resources in Queensland, a drought-stricken state, are the priority here and we will make sure that we do the proper environmental assessments as we have to do by law in this state," she said.
Premier Annastacia Palaszczuk wants to see Adani's rail plan before it gets approval.
Australian Associated Press