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.
Italian oil and gas company ENI owns the Blacktip gas project and has interests in Bayu Undan, Darwin LNG, the Evans Shoal gas field and the shuttered Woolybutt oil field.
Santos and ENI are looking for solutions for CO2 and removing old facilities in the waters north of Darwin. Time will tell if the problems are solved or just delayed.
ENI's plan to sell out of Australia and leave offshore decommissioning liabilities to others has struck trouble from regulator NOPSEMA and new Government policy proposals.
An eight year wait for ENI's Woollybutt oil field to be decommissioned and poor maintenance have caused subsea kit to surface and pose a danger to vessels.
