There is a low risk of further breaches of the tailings storage facility (TSF) or a breach of the New Alamasi water dam at the Williamson Mine in Tanzania, a Petra Diamonds assessment team has concluded.
The wall breach took place on 7 November.
Petra said a 6-meter high wall was constructed to close the breached wall area and, as a precautionary measure, it also constructed containment walls upstream and downstream of the New Alamasi water dam.
The buttressing of the New Alamasi dam wall is also underway.
Petra said several diversion trenches are also being constructed to prevent any water build-up and to enable rainwater to flow into the surrounding rivers and streams.
Meanwhile, 12.8 million cubic meters of water and tailings material were released from the TSF as a result of the breach.
“A total area of 3.57 km2 is covered with this material on Williamson’s mine lease area with 1.52 km2 outside the mine lease area,” said Petra.
“Environmental work to date confirms the tailings material which flowed out of the TSF is inert.”
Petra reconfirmed that no fatalities or serious injuries occurred as a result of the incident.
A socio-economic study, supported by an external social impact specialist, is also at an advanced stage to determine socio-economic impacts.
Mathew Nyaungwa, Editor in Chief of the African Bureau, Rough&Polished
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