Victorian environmental campaigners are launching landmark legal action against the state's Environment Protection Authority and three coal power stations over claims they failed to limit climate pollution.
Led by conservation group Environment Victoria, the Supreme Court case will be the first to test Victoria's Climate Change Act, which was introduced in 2017.
It will also be the first challenge to the regulation of air pollution from the state's coal-burning power stations.
The owners of Loy Yang A, AGL Energy; Loy Yang B, Alinta Energy; and Yallourn, EnergyAustralia are cited in the legal action.
Environment Victoria will allege the EPA "failed to protect the health of the community and the environment" by not taking any action against these three coal power stations while reviewing their licences in March this year.
"The Andrews government passed nation-leading climate change legislation in 2017, but Victoria's environment watchdog chose to ignore it when making a crucial decision about coal power station licences this year," EV chief executive Jono La Nauze said.
"The EPA took more than 1200 days to review the licences of three coal power stations and then failed to take any action on the greenhouse gases they emit.
"Our case will argue that they failed to properly consider key sections of the Climate Change Act and the Environment Protection Act."
AAP contacted the EPA for a response, however it declined to comment due to the upcoming court case.
Coal power station owners Alinta Energy, EnergyAustralia and AGL also declined to comment on specifics of the case, while the matter is in court.
An AGL spokeswoman said it acknowledged its role in energy transition and is committed to ensuring this is done responsibly "balancing Australia's current and future energy needs with the commitment to decarbonise".
An EnergyAustralia spokesman said it had a strong record of environmental compliance and a commitment to improvement.
"EnergyAustralia is committed to being a leader in environmental stewardship and the responsible operation of our assets is paramount," the spokesman said.