Under the EPBC Act, the Minister must decide based on whether a project will have a significant impact on a matter of national environmental significance. This includes threatened species and ecological communities, World Heritage areas, National Heritage (including First Nations heritage) and a number of issues covered by international agreements, such as migratory birds and wetlands.
In the case of the North West Shelf, the facility and activity have been continuing for many years and the application was for a time extension (not an expansion). The only issue the Minister could legitimately consider here was the impact of the project on First Nations heritage (the Murujuga petroglyphs).
The Minister has given provisional approval with a number of proposed conditions that are not yet public, but we assume relate to local air pollution that might affect the petroglyphs. The process demands that the Minister give the proponent 10 business days to respond to the proposed conditions before the decision is finalised and published.
Separate to the EPBC process, all facilities that emit more than 100,000 tonnes of CO2 equivalent greenhouse gases per year are subject to the Safeguard Mechanism. The North West Shelf is one of the 215 facilities that are covered.
Under the Safeguard Mechanism, all facilities have an emissions cap set by the Government, which reduces over time. There is also an overall carbon budget of 1.233 million tonnes of CO2 equivalent for the entire mechanism (all 215 facilities combined) between 2020 and 2030. So the North West Shelf extension will have to fit within that, and also subsequently within any future carbon budget set after 2030, which, under the Climate Change Act 2022, will have to be consistent with achieving net zero by 2050 (and any interim targets, eg for 2035). What this means is that, any emissions from the facility that exceed these limits will have to be reduced or paid for by the proponent.