Exclusive: WA minister gave consent to BHP plan just three days after Juukan Gorge site was blown up by Rio Tinto in a move that has horrified the public

Mining giant BHP Billiton is poised to destroy at least 40 – and possibly as many as 86 – significant Aboriginal sites in the central Pilbara to expand its $4.5bn South Flank iron ore mining operation, even though its own reports show it is aware that the traditional owners are deeply opposed to the move.

In documents seen by Guardian Australia, a BHP archaeological survey identified rock shelters that were occupied between 10,000 and 15,000 years ago and noted that evidence in the broader area showed “occupation of the surrounding landscape has been ongoing for approximately 40,000 years”.