A West Coast mine is looking to shore up its output well into a second century with a proposal to build a new tailings dam with a 140 hectare footprint.
In a proposal to the federal department of environment, Chinese-owned Rosebery miner MMG stated its intentions to construct a new tailings dam with a 42-year lifespan.
"The [new tailings storage facility] has been designed as an off-stream facility with storage volume of approximately 25 Mm3 and an anticipated lifespan of around 42 years (based on current tailings production rates)," the proposal published on the Environmental Protection and Biodiversity Conservation Act website said.
In a section titled matters of national environmental significance, the EPBC Act asked proponents to list possible ecological threats it anticipated in its proposal.
MMG ticked the box for yes when asked "is the proposed action likely to have any direct or indirect impact on the members of any listed species or any threatened ecological community, or their habitat?"
"There is potential for impact on threatened fauna species," the proposal reads.
The threatened species include wedge-tailed eagle, masked owl, Tasmanian devil and the spotted tail quoll.
It further listed a possible impact on one listed threatened ecological community, 10 listed threatened species, eight listed migratory species and 12 listed marine species.
However, the proposal said contractor North Barker Ecosystem Services considered "none of the impacts on threatened fauna species are considered to be significant".
The Bob Brown Foundation, however, said the company "should abandon this insane plan".
"MMG's own reports show this proposal will destroy 285 hectares of rainforest and melaleuca forest, to accommodate their 140 hectares of tailings dams and pits," BBF Tarkine campaigner Scott Jordan said.
"That is dams and pits 70 time larger than the Melbourne Cricket Ground, and a total disturbance twice that amount.
We are blockading the access road to these rainforests to defend and protect them.Scott Jordan
"Our foundation has operated a blockade against logging and mining in this area since December and have regularly sighted Devils, Quolls and Wedge tailed eagles, and have heard calls from Masked owl hunting in the area".
"MMG should abandon this insane plan, and [Federal environment minister Sussan] Ley should use her powers under the act to declare this proposal clearly unacceptable and end this folly.
"Until they do we are blockading the access road to these rainforests to defend and protect them."
MMG has been contacted for comment.