Hunter health workers and community groups have condemned the federal government's approval of two coal mining extension projects in the Hunter.
Whitehaven Coal's Narrabri Underground Mine Stage 3 Extension Project was also approved.
It is estimated the projects will lock in about 1.5 billion tonnes of lifecycle greenhouse gas emissions - more than three times Australia's total annual emissions.
Newcastle-based rheumatologist and Doctors for the Environment member John Van Der Kallen said the mining, transportation and burning of coal had many adverse health effects for those living or working near coal operations.
"Locally we see dust pollution increasing the incidence of airway disease, heart disease, stroke and cancers," Dr Van Der Kallen said.
He agreed with other critics who said the latest mining extensions would effectively "supercharge climate change".
"In Australia and globally we are seeing worsening climate events with droughts in South America, cyclones in southeast Asia and extreme bushfires in Portugal," he said.
"These are due to rising global emissions and it must stop if we are going to have a stable climate and a safe and healthy population."
Denman Aberdeen Muswellbrook Scone Healthy Environment Group president Wendy Wales said the approvals flew in face of attempts to transition Hunter communities to a clean energy future..
"We struggle in the Upper Hunter, or in Australia really, to fathom Australia's role in putting fuel on the fire of climate change," she said.
Australian Conservation Foundation campaigner Gavan McFadzean said the approvals were the latest in a long list of broken promises on the environment.
"This decision is the opposite of climate action. Together, these coal mines will generate more than 1.3 billion tonnes of lifetime emissions," he said.
But Minerals Council of Australia chief executive Tania Constable said the approvals would safeguard jobs and economic stability in a region that relied on the industry.
"These projects have faced lengthy delays due to appeals exploiting legal loopholes in our environmental laws, driven by third parties disconnected from the needs of local communities," she said.
"While the courts ultimately dismissed these claims, it hasn't come without a cost to the taxpayer and local communities."
The Mt Pleasant and Narrabri projects were among 19 coal and gas projects Environment Justice Australia, acting on behalf of Environment Council of Central Queensland, applied under federal laws to have thrown out before they had completed their full environmental assessments.
The group argued the potential emissions from the projects should rule them out of any further consideration.
The federal approval for MACH Energy's Mt Pleasant project followed last month's Land and Environment Court ruling that upheld the Independent Planning Commission's 2022 approval of the 444 million tonne project.
It followed a Federal Court ruling in May that ruled Ms Plibersek was not legally required to assess risk to the environment from the climate harm of the mine's expansion.
