The Environment Protection and Biodiversity Conservation Act 1999 (Cth) (EPBC Act) does not necessarily override State law. The Act establishes assessment and approval requirements that are to be considered in addition to existing approvals required under State law. This means that an action still needs to be approved under all applicable State laws as well as under the EPBC Act. Under the Act, the Commonwealth can enter into a bilateral agreement with the State or Territory, which has the effect of delegating the Commonwealth's assessment and approval powers to the State or Territory Government. There is a current bilateral agreement between South Australia and the Commonwealth.

The Commonwealth has recently revised its assessment bilateral agreement with South Australia and intends to implement an approval bilateral.