Date: Feb 22, 2019
Iron ore giant Rio Tinto has revealed details of its 136 tailings dams as pressure builds on the mining sector to demonstrate the safety of the practice after hundreds died when a dam burst in Brazil earlier this year.
Tailings dams store toxic waste produced as a result of mining operations and can be built with several different methods.
The Brazilian disaster on January 25 occurred after an upstream dam burst at South American iron ore miner Vale’s Brumadinho facility.
Upstream tailings dams are expanded by sequentially adding to the crest of the dam wall. The safety of upstream dams was also highlighted in 2015 when a BHP and Vale dam burst, destroying a South American village and killing 19.
On Monday Brazil’s government totally banned the construction of new upstream-method dams and ordered all existing dams be decommissioned by 2021.
Of Rio Tinto’s 136 tailings dams, 36 are closed and of the 100 active dams, 21 were built using the upstream method.
The company has 12 dams in Australia; one in the Northern Territory, eight in Queensland and three in WA.
The company said all of its dams, whether active or inactive, had an external engineer of record or design engineer.
Rio Tinto chief executive Jean-Sébastien Jacques moved to allay any concerns over the dams.
“In light of this tragic event, Rio Tinto is again reviewing its global standard and, in particular, assessing how we can further strengthen the existing external audit of facilities,” he said.
