The fourth respondent (SAFAM) operated a composting facility on a farm in Robertson, adjacent to properties owned by the appellants, which form part of a protected nature reserve used for tourism. SAFAM commenced composting activities in 2017 and later applied for environmental authorisation under s 24 of NEMA and a waste management licence under NEM:WA. The appellants, as interested and affected parties, opposed the applications, alleging that SAFAM had unlawfully commenced listed activities without prior authorisation in breach of s 24F of NEMA. After the Department rejected SAFAM’s applications, SAFAM brought a review application. That review was settled between SAFAM and the Department, resulting in a High Court consent order in October 2019 which set aside the Department’s decisions, condoned late submission of reports, and paved the way for authorisations to be granted. Environmental authorisation and a waste management licence were subsequently issued. The appellants did not challenge or seek rescission of the settlement order but later brought review proceedings to set aside the authorisation and licence, which were dismissed by the High Court, leading to this appeal.