AngloGold Ashanti Brazil tailings update
Tailings-related regulations introduced in Brazil in 2022, required AngloGold Ashanti Brazil to conduct a new detailed risk assessment of its portfolio of tailings storage facilities (“TSFs”). The regulations required this new risk assessment be conducted with oversight from an independent expert.
One of the findings of this review was to increase buttressing of the Calcinados TSF to align its post liquefaction factor of safety with the standard applied in Canada, which is currently considered best practice.
AngloGold Ashanti will proceed with this buttressing programme and has therefore suspended filtered tailings deposition on the facility, which services the Cuiabá Mine Complex.
It is important to note that the operational and structural integrity of the Calcinados TSF remains safe and stable, per the conclusions of recent assurance assessments by independent tailings experts and the company’s own TSF team. The facility’s factors of safety – in both a drained and undrained state – are fully compliant with relevant Brazilian operating regulations.
Information on the timeline for the completion of this buttressing programme is expected to be provided after engineering and geotechnical work has been completed by independent tailings experts.
Processing of gold concentrate at the Queiroz plant, which also services the Cuiabá Mine Complex, will also be suspended until this buttressing programme has been completed. In the meantime, mining of ore is continuing at the Cuiabá Mine Complex.
During this period, the Company expects that both sites will continue to extract gold from the gravity circuit at a rate of 5,000oz on average per month and will produce gold in concentrate at an average of approximately 10,000oz per month, with options being assessed to sell gold concentrate until the Queiroz plant resumes operation.
For the twelve-month period ended 30 September 2022, the Cuiabá Mine Complex produced 257,00oz at an all-in sustaining cost of $1,439/oz.
