Mining giant Rio Tinto has admitted it had three other options to expand its iron ore mine that could have avoided the destruction of cultural heritage at Juukan Gorge in Western Australia's Pilbara region in May.
In a submission to a Senate inquiry on the destruction of the 46,000 year old rock shelters at Juukan Gorge, the mining giant said it had chosen the fourth option, which impacted the rock-shelters to "access higher volumes of high-grade ore".
Rio Tinto also acknowledged that the mine manager had been informed by PKKP heritage manager Dr Heather Builth that the site was one of the "top five" most significant in the Pilbara, months before it was drilled and detonated.
"The Manager of Mine Operations' recollection is that Dr Builth said something along the lines of: 'Is that gorge/cave going to be taken out by the puts? It would be in the top 5 of location in the Pilbara with respect to cultural importance'," the submission read.
"He was not sure to where Dr Builth was pointing. He thought he might have been pointing at the 'Juukan shelter gorge', but he was not sure.
"As he was not sure to which site Dr Builth was referring, he did not give a definitive answer."
Archaeologist Dr Michael Slack also informed Rio Tinto that one of the rock shelters, Juukan 2, was of "the highest archaeological significance in Australia".
In his 2018 report, Dr Slack wrote that "the Juukan-2 rockshelter has the amazing potential to radically change our understanding of the earliest human behaviour in Australia".
"To date there is no other site of this age with faunal remains in unequivocal association with stone tools. The significance of this cannot be overstated."
The rock shelters were destroyed on May 23. The Puutu Kunti Kurrama and Pinikura Traditional Owners were made aware of the planned blast on May 15.
Rio Tinto had drilled 382 blast holes and loaded them with explosives before the PKKP had learned of the plans - they issued an urgent request to stop the blasts five days before the detonation.
But "Rio Tinto did not consider it feasible to remove the shot from the holes to protect Juukan 1 and Juukan 2."
"There was insufficient time to do so safely given the limitations on the stability of the explosives and the unacceptable environmental and safety risks."
Rio Tinto obtained ministerial consent to destroy or damage the sites from the Western Australian Government.
In the WA Government's submission to the Senate inquiry said the destruction of the caves was 'devastating for all parties involved and was clearly avoidable'.
The submission also admitted that the Aboriginal Heritage Act has "been a source of conflict involving Aboriginal people and land use proponents" and that "penalties for infringement are very low in comparison to other Australian states and territories".
It said the laws are "ourtdated" and in need of an overhaul.
Rio Tinto chief executive Jean-Sebastien Jacques, as well as the WA and federal governments are due to appear at the Senate inquiry's first public hearings on Friday.
A spokesperson for the PKKP told NITV News they would not make comment while the inquiry proceedings are underway.