The Pamoja Critical Minerals Alliance (PCMA) Zimbabwe Chapter has raised alarm over a toxic waste spill from a copper mining operation in Zambia, warning of severe environmental and social consequences for communities in the region and calling for stronger accountability from the mining sector.
The spill happened on Feb. 18 when a tailings dam that holds acidic waste from a copper mine in the north of the country collapsed, according to investigators from the Engineering Institution of Zambia.
The collapse allowed some 50 million liters of waste containing concentrated acid, dissolved solids and heavy metals to flow into a stream that links to the Kafue River, Zambia’s most important waterway.
“The Sino-Metals Leach induced disaster on 18 February 2025, which released 50 million litres of acidic effluent, contaminated the Kafue River, a major tributary of the Zambezi River that flows through Zimbabwe and Mozambique into the Indian Ocean, and is harmful to people, animals and plants,” reads the solidarity statement.
The Kafue, a major tributary of the Zambezi River, provides drinking water for much of Zambia’s population and is a vital freshwater source for over 60% of the country.
PCMA said around 44% of Lusaka’s residents rely directly on the river. The spill has also affected communities along the Zambezi basin in Zimbabwe and Mozambique, which depend on the river for water and livelihoods.
The group reported that the disaster contaminated farmland, destroyed crops, killed livestock, and disrupted the livelihoods of more than 300,000 smallholder farmers in Zambia.
“The incident is not isolated and is part of a broader pattern of extractivism reflected in environmental damage caused by foreign mining companies in Zambia and the SADC region” the alliance said, linking the incident to broader patterns of environmental risk associated with foreign mining operations in Zambia and across the Southern African Development Community (SADC) region.
PCMA cited other companies it said had faced similar accusations of discharging untreated waste into the watershed. Rongxing Investments has been accused of toxic spills into Blue Stream, a Kafue tributary, while Mimbula Mine, owned by Nkoya Resources, was linked to a January 2025 spill. Ozone Mine, a Chinese-owned operation, has also been accused of discharging chemical waste that caused crop failures and waterborne diseases.
The alliance called on Zambia and SADC governments to strengthen enforcement of mining regulations, adopt independent investigations into environmental damage, and align with international standards such as the Global Industry Standard on Tailings Management, introduced in 2020. That framework was developed following the Brumadinho dam collapse in Brazil that killed 270 people.
It also urged mining companies to provide adequate compensation to affected communities and commit to long-term recovery efforts.
Copper is central to Zambia’s economy, accounting for most of its export earnings. The metal is also critical to renewable energy technologies such as wind turbines, solar panels, and electric vehicles. But PCMA said that unlocking Zambia’s full potential in critical minerals required addressing governance challenges and preventing further environmental damage.
“Zambia’s National Critical Minerals Strategy emphasises maximising benefits for the people, but these objectives cannot be met without accountability in mining operations,” the group said.
A smaller acid waste leak from another Chinese-owned mine in Zambia’s copper belt was discovered days after the Sino-Metals accident, and authorities have accused the smaller mine of attempting to hide it.
