Under the $5.3 billion proposal, Waratah Coal Ltd wants to develop a mine, pipeline, railway and port facility in Alpha and the Shoalwater Bay areas in Queensland.
The state government has been in discussions with Waratah about its proposal, but the federal government could use the Environmental Protection and Biodiversity (EPBC) Act to stop the development going ahead.
During Senate question time, Australian Greens Senator Christine Milne asked whether the commonwealth would block the project, saying it would produce 50-100 million tonnes of coal a year.
Senator Milne said the project was "clearly unacceptable" as the port would be located in RAMSAR-protected wetlands and would threaten endangered species like dugongs and loggerhead turtles.
Climate Change Minister Penny Wong said Environment Minister Peter Garrett received a referral from the company on July 31.
"And the minister has yet to make a determination on this proposal," she said.
"So obviously some of the issues you raised, may be amongst those the minister will have to consider in the context of that EPBC ... consideration."
The proposal would be closely examined for potential impacts in areas including the Great Barrier Reef world heritage area and the Shoalwater and Corio Bay RAMSAR sites, Senator Wong said.
"It is the case that the government and this minister are committed to proper and transparent administration of the EPBC Act," she said.
"The minister's decision is within the context of the statutory framework and he has to have regard to issues under the Act accordingly.
"In the context of a statutory discretion, there is no such thing as an automatic rejection and I'm sure the senator would be aware of that."
