On 27 July 2021, the SociedadeMineira de Catoca (Catoca) reported a leakcomprised of natural rocks and clay from a tailings basin at its mining operations.
Catoca acted immediately to stem the flow of the leak, sealing the breach by the end of July. This involved shoring up the existing basin and building three new dykes.
The tailings basin itself has never contained external chemical components, such as hard metals. Instead, it has only ever held a mixture of water, sand and clay; a composition similar to the mudflows of Angola’s rainy season, which altered the oxygen levels within the river water.
Samples taken from wide-ranging sourcesby independent laboratoriesconfirm that at no point there have been any heavy metals present in river water flowing from the tailings basin. By September, the oxygen levels were returning to normal.
Supporting local communities
Catoca has had conversations with community representatives across more than a dozen sites in order to understand what support people may need.
Catoca’s priority now is minimising the impact of this breach on local communities through providing food stamps and wider support, and on preventing such an accident from ever happening again.
Catoca will commission independent environmental and structural audits, to be carried out by reputable experts, to reconfirm that there has been no environmental damage, to minimise the risk of future problems, and to work towards international standards.