Toxins from South African mines threaten city

Toxic liquids building up in defunct gold mines beneath Johannesburg could reach environmentally dangerous levels by June 2012, officials and scientists said yesterday.

Work is to begin immediately on a chain of pumping stations and treatment plants.

Water has already started leaking from abandoned mines west of Johannesburg in the so-called Western Basin.

Water accumulating in shafts dug more than a century ago has been reacting with rocks to produce sulphuric acid, heavy metals, toxins and radiation.