The green light for Black Mountain Energy comes just months after Federal experts said its environmental risk assessment was "limited and disjointed" and reached "largely unsupported" conclusions.
If the US miner is found to have mined too close to a large jarrah tree, it would trigger an automatic cancellation of its right to mine much of its lease.
Chevron's Gorgon LNG project on Barrow Island began operating in 2016 has the world's largest carbon capture and storage system dedicated to emissions reduction.
Chevron chief executive John Watson says his company should have done more engineering and planning before it sanctioned the Gorgon LNG project in 2009.
Too much hot air around the LNG trains on Barrow Island has caused Chevron to flag a production cut at Gorgon as the US giant tackles problems onshore and offshore.
In early 2017 Chevron's rush to ship the first LNG from the $US54 billion Gorgon project to meet its chief executive's deadline had disastrous consequences.
Australia's Petroleum Resources Rent Tax has incredibly generous annual uplifts in allowable deductions that will likely see little or no payments from its offshore LNG projects.
The first two processing facilities at the Gorgon LNG project are operating near capacity and commissioning of the final train is under way, with production expected early in the second quarter of 2017.
