A proposed expansion of the port near Bowen, a day's drive south of Port Douglas, to enable coal exports to increase from 15 to 50 million tonnes a year will put thousands of jobs and the environment at risk, along with billions of dollars in revenue according to Australian Greens leader, Bob Brown.

Mr Brown was in north Queensland on Sunday to inspect the site which is likely to be sold off as part of the Queensland Government's privatisation push.

'In Gladstone, Mackay, Townsville or Bowen, there is big concern about lifestyle and the 60,000 jobs the Barrier Reef supports and the $6 billion per annum economy which is threatened by the coal industry.' he said and added that there are double the number of jobs in the reef than in the mining industry.

'If climate change keeps going as it is, the Barrier Reef is in great danger by mid-century and those jobs with it.'

"Such an expansion would see more coal ships travelling through, and putting at risk, Australia's tourism hub worth $60 billion annually and employing 60,000 people," he said, citing the impact on important wetlands and the world heritage listed Great Barrier Reef.

This isn't the first time the reef has been under threat from the coal industry. In April, the Chinese coal carrier the 'Shen Neng' ran aground on Douglas Shoal, spilling around four tonnes of oil and leaving a three-kilometre scar on the reef.

'They (Governments) have an obligation to ensure that the environment is not affected by that sort of infrastructure that will see a big increase in coal shipping through the Barrier Reef,' Senator Brown said.