Subject to the other provisions of this chapter and chapters 2, 3 and 5, another Act relating to the granting of overlapping authorities for GHG authorities or an authority under that Act does not limit or otherwise affect--
(a) the power under this Act to grant a GHG authority over land in the area of an overlapping authority for the proposed GHG authority; or
(b) the carrying out of authorised activities for a GHG authority.