/ 5 November 2011

Jo’burg faces threat greater than acid mine drainage

At least 380 mine dumps and slime dams around Gauteng could be a bigger threat than acid mine drainage, the Saturday Star has reported.

A draft report by the provincial agriculture department and rural development on mine residue areas (MRAs) found that the mine dumps were causing radioactive dust fallout, toxic water pollution and soil contamination, the paper said.

It warned that if the province did not act, Johannesburg would eventually be seen as “an old mining town that has reached the end of its working life”.

Wind-blown mine dust being inhaled could cause respiratory diseases, it said.

The report — which has not been released yet — found that most MRAs including mine dumps, waste rock dumps and water storage facilities were radioactive because “the Witwatersrand gold-bearing ores contain almost 10 times the amount of uranium in gold.

“These radioactive tailings co-exist in these MRAs alongside the iron sulphide mineral pyrite, which reacts in the presence of oxygen and water to form a sulphuric acid solution – the main cause of acid mine drainage,” the report said.

The newspaper reported that the department would survey and map all MRAs “with a view to determining the physical location of each source of hazard — chemical, radiological and physical” and quantify risks. — Sapa-M&G staffer