Chinhoyi — At least 20 head of cattle have died of suspected cyanide poisoning in Mashonaland West Province in a development attributed to improper handling of the dangerous substance's residue.The deaths occurred since the beginning of the rainy season, which has resulted in the existing residue management infrastructure giving in and discharging into the environment.
Cyanide is a hazardous substance used in recovering gold during mining operations and has catastrophic consequences on the environment, particularly on humans and animals if improperly handled. In the first incident, which occurred on December 6, seven cattle died in Zvimba from cyanide poisoning.
Investigations so far show that a pump failed due to excess rains, resulting in residue overflowing out of a mill confinement.
It flowed into the environment and cattle came into contact with the contaminated vegetation, resulting in death.
Breaches of environmental laws were confirmed and protection orders were issued by the Environmental Management Agency.
"The pump that conveys slurry from the CIP to the slimes dam had failed due to rain. Traces of slurry overflowed out of the fenc,e resulting in animal poisoning," reads part of the findings from EMA.
"The active tailings dam also released some slurry due to heavy rains, which were held in the return ponds."
Another 12 cattle belonging to three different farmers also succumbed to cyanide poisoning at Eiffel Gold Mine in Kadoma.
This was after drinking waste water suspected to be contaminated with residual cyanide. The incident, which occurred on December 18, shows that excessive rains destroyed overflow control walls at the mine, resulting in storm water overflowing outside the mine fence into the environment.
Results of water samples collected at the scene and taken to the laboratory showed high levels of residual cyanide.
"Water samples were collected and sent to the laboratory for analysis to establish the presence of residual cyanide in the storm water. The laboratory results revealed that the samples collected had very high levels of residual cyanide that is way above the prescribed levels," reads the EMA report.
Another cow died in Sanyati District at Magisa Mine after also drinking suspected cyanide-contaminated water.
EMA Mashonaland West provincial spokesperson Mr Munyaradzi Nhariswa said environmental protection orders have been issued to all offending mines.
"The orders issued require mines to adopt necessary environmental protection measures to contain overflows during this rainy season.
Cyanide is classified as a hazardous substance and its use, storage and waste disposal is done in terms of Statutory Instruments 12 and 6 of 2007. The offending mines have accepted liability and have offered to restitute the people whose cattle were killed in the incidents.
Mr Nhariswa appealed to all gold ore millers to put environment protection measures and to put secondary spillage control measures. "All cyanide users should have cyanide antidote and ferrous sulphate on site to detoxify the cyanide in cases of any suspected breaches," he said.
He said all spillages should immediately be reported to EMA and the Zimbabwe Republic Police, while efforts should also be made to notify downstream users whenever a breach is suspected.