The 400km2 of bright yellow mine dumps scattered around the province are laden with 600,000 tons of the radioactive heavy metal uranium, inadvertently excavated through gold mining processes over the last century.

“Gold and uranium occur in the same geological environment and with gold mining, uranium is often also brought to the surface,” explains Professor Frank Winde, a North-West University geographer. “Uranium is more common than gold and for every 10g of gold excavated, 100g of uranium was also brought to the surface. Mine tailings in the Witwatersrand are estimated to contain around 600,000 tons of uranium.”

Uranium is passed on to humans either through the inhalation of fine dust particles from these tailings and can be blown as far as 20km on a windy day, or when mine water seepage enters rivers.

Uranium occurs naturally in the environment and low levels of exposure can be tolerated by humans, but there are well-documented health risks associated with higher levels. These including kidney damage and disease, neurological problems and cancer. It is also an endocrine disrupter that mimics the hormone, oestrogen, which is particularly harmful to pregnant women as it can cause birth defects and developmental delays in their babies.

1.6 Million people live in informal settlements close to radioactive mine residue areas.  The majority of mine residue areas are radioactive because the Witwatersrand gold-bearing ores contain almost ten times the amount of uranium than gold.

1.6 Million people live in informal settlements close to radioactive mine residue areas. The majority of mine residue areas are radioactive because the Witwatersrand gold-bearing ores contain almost ten times the amount of uranium than gold.