By MUKOSELA KASALWE
FIRST Quantum Minerals’ Kansanshi Mine has established a pioneering water recycling system using cutting-edge technology to prevent effluent from getting into external water bodies, says company environmental manager Arnold Malambo.
Mr Malambo said there were three main sources of contaminated water on a mine site – process water, mine drainage and surface run-off.
“Water is a very important resource in mining. Without adequate amounts of water, your processing can be affected,” he said.
Mr Malambo noted that meeting minimum compliance standards regarding environmental pollution was a common problem for mines the world over.
“What we have done better than other mines is that we have been able to maintain a zero rate of discharge into the receiving environment,” he said.
In 2015 Kansanshi developed a rigorous water recycling system to ensure contact water does not reach the natural environment even after it had been treated in the sedimentation ponds along the mine’s water treatment system.
Any incidental overflows from the process plant go through a series of sedimentation points where solids are settled before going to a final pond at the compliance point. Here, the treated water is pumped back to the process system for reuse through a 1.7 kilometer long pipe.
The mine, which is also Zambia’s largest taxpayer, has installed an automated monitoring system to ensure the effluent remains within Zambia Environmental Management Agency (ZEMA’s) minimum requirements. The system also has an early warning system that generates ‘SMS’ notifications to environmental and process staff if water levels approach a critical point, to avoid pond overflows.