The ongoing noxious odour in the Centurion area is as a result of the illegal disposal of an oil-based substance into Sunderland Ridge Wastewater Treatment Works which occurred on January 8.
City of Tshwane’s MMC for Environment and Agriculture Management, Ziyanda Zwane, said the City was aware of the unpleasant smell endured by residents in the area.
He said: “This substance has a high volatile organic compound concentration, meaning that it releases a vapour in the atmosphere, which causes the odour being experienced.”
He said the odour would continue to be detected, especially in the morning, late afternoon and at night until the substance is fully diluted and moves through the natural environment.
“Please also note that, due to the substance being an oil, it does not dissolve in water and it ‘coats’ everything it comes into contact with. Hence, with its associated odour, the oil will linger in the environment much longer than a water-based substance that may quickly be washed away,” he said.
Zwane described the incident as a once-off illegal activity, adding that his department was working continuously. They were monitoring the river and wastewater treatment works outlet, assessing the site and receiving environment reports daily.
They were also stopping all liquid waste transport vehicles observed in the area to verify legality of operation.
He said expected results of water samples taken would assist in determining the chemical composition of the substance disposed of and its pollution impact on the river.
“This will provide more information on possible treatment options and health risk management going forward. Once the results are in, the community will be updated on the state of the receiving environment regarding any new precautions to be taken,” he said.
Two suspects, he said, were identified and can be directly linked to the illegal disposal of the oily substance in question at Sunderland Ridge Wastewater Treatment Works.
Zwane said: “A criminal investigation is currently under way in terms of contraventions under the National Environmental Management: Waste Act, 2008 (Act 59 of 2008) in association with the national Department of Forestry, Fisheries and the Environment. If found guilty, a R10 million fine, imprisonment of 10 years or both may apply.”