A group of teenagers filed a class action injunction in the Federal Court in September seeking to stop the approval of the Vickery extension project despite it receiving state approval.
Whitehaven is seeking consent to increase the approved Vickery coal project to operate an up to 10 million tonnes per annum open cut metallurgical and thermal coal mine, with onsite processing and rail infrastructure.
On August 12, the NSW Independent Planning Commission approved the project.
The project is being reviewed by the federal Department of Agriculture, water and the environment for environment protection and biodiversity conservation approval.
"A decision from DAWE is expected in the near future, subject to the injunction application seeking to restrain the federal minister of agriculture, water and the environment from issuing the project with an EPBC approval," Whitehaven said.
The injunction application was heard by the court in March.
Eight people aged from 13 to 17 - many of whom met during the School Strike 4 Climate -argued that federal agriculture, water, and environment minister Sussan Ley should not allow the mine to proceed because she had a common law duty of care to young people and to prevent climate change.
One of the eight students, Izzy Raj-Seppings, 13, said approval of the mine would make climate change worse and harm her generation in the future.
"We're trying to get the federal environment minister to prevent the Vickery coal mine going ahead because we believe she has a duty of care for young Australians and young people all over the world," Raj-Seppings reportedly told the ABC.