Ann: Cadia Northern Tailings Dam, page-5

I think you may be stirring the possum somewhat Grajem12?

This is what was in today’s announcement
“The tailings material is a slurry of finely ground rock, water and a low level of benign processing reagents. Cadia uses a gravity circuit to recover gold, with the remaining gold and copper reporting to a concentrate which is exported to copper smelters. Cadia does not use a chemical reduction process to recover gold – that is, the gold extraction process does not involve the use of substances such as mercury, cyanide and arsenic.


This was from
https://en.wikipedia.org/wiki/Bento_Rodrigues_dam_disaster

On 9 November, the city of Governador Valadares stopped the water intakes due to the mud on the Rio Doce. The next day, a State of Public Calamity was decreed in response to the water shortage in the city. According to analyses carried out in the city, the mud contains greater than acceptable concentrations of heavy metals, substances harmful to health, such as arsenic, lead and mercury.[14]

There is no comparison between the two!