How it happened …
● In 1988, Natal Parks Board scientist Angelo Lambiris finds deformed tadpoles with high mercury levels close to the Thor factory.
● In the early 1990s in Cato Ridge, several Thor workers, including Peter Cele, Engelbert Ngcobo, Frank Shange and Felix Mhlanga, are admitted to hospital, where they die. A series of civil actions begins as families seek compensation from Thor in the UK. Some workers receive out-of-court settlements. In SA, culpable homicide charges against Thor managers are dropped. The company pleads guilty to factory safety violations and pays a R13,500 fine.
● In 1995, then president Nelson Mandela appoints a commission of inquiry into Thor, chaired by judge Dennis Davis, to investigate the origin of the mercury-waste stockpile and to recommend how to deal with it.
● In 1997, Davis’s report shows Thor received waste from AECI, Borden Chemicals, Calgon and American Cyanamid (US), Thor (UK) and other companies in Europe, South America, the Middle East and Indonesia.
Evidence presented to the inquiry shows supervisors were not adequately skilled. Davis concludes that “it must have been clear to any reasonable person” that imported waste could not be treated safely at Thor.
Government regulators had also “grossly mishandled” the emerging crisis and in 1994, when government inspectors visited the factory, they found mercury leaking out of storage drums to beneath the concrete floor, permeating the soil to at least a metre.
The final upshot of the inquiry is that Thor should pay to dispose of the waste safely. The government will cover incidental expenses. ● But Thor — facing compensation claims from workers in UK courts — begins to alter its corporate shape. A new company, Tato Holdings, emerges in the UK. Thor Chemicals ceases to exist in name in SA after new entities emerge, such as Metallica, Guernica and Acti-Chem.
● More than 20 years after Davis called for a speedy resolution of the waste scandal, very little has happened — amid indications that mercury pollution continues to seep slowly towards Inanda Dam, either from previous or continuing leaks from the Thor stockpile and outdoor sludge dams.
● During 2015, media reports say some of Thor’s mercury waste has been moved to Gauteng, but was destroyed in a fire that gutted the A-Thermal incineration plant in Olifantsfontein.
● In 2019, another fire breaks out in the heart of the Cato Ridge stockpile.