Provincial Agriculture, Conservation, Environment and Land Affairs MEC Mary Metcalfe said Gauteng, which constitutes a mere 1,4% of South Africa's land area, generates 80% of the country's waste.
She said Gauteng, which is home to nearly 20% of South Africa's population of more than 40-million people and accounts for 40% of national economic activity, generates 4,3-million tons of domestic waste, 14 000 t of medical waste and 1,8-million tons of hazardous waste every year.
Power stations and mining operations account for the bulk of the industrial waste generated in Gauteng.
"All of this waste is disposed of by landfilling or incineration, but landfills in the province have a finite lifespan and incineration affects our air quality," said Metcalfe, adding that the yearly cost of collecting and disposing of waste in Gauteng is estimated at R340-million.
She added that, with landfills filling up, a suggestion has been made to find alternative waste-dumping sites outside the province.
But Mecalfe criticised this suggestion as an unethical one, saying: "It is unfair for us to dump our waste in other provinces." She said the problem of a shortage of dumping sites in Gauteng would be postponed by several years if the recycling of waste was undertaken more vigorously.
She added that the province's air quality was a cause for serious concern.
"Vehicle emissions are the biggest single source of poor air quality, followed by domestic coal burning.
"Industrial coal burning adds to this problem, and so does heavy industry. The pollution generated by industry in the Vaal and Sasolburg areas makes this the key air-pollution hot-spot for the province.
"The knock-on effects on the health budget of the direct health effects resulting from waste and pollution are not measured, but can be assumed to be considerable.
"In the long term, these risks and the financial implications of treatment are likely to escalate if no preventive measures are taken.
National Water Affairs and Forestry Minister Ronnie Kasrils said most of the active gold-mines in the Witwatersrand basins discharge highly-saline underground water into an already salinated Vaal River system, South Africa's most strategic water resource.
He described as unacceptable the fact that rivers in Gauteng are polluted with raw sewage and coliform bacteria.
"This is mainly a result of the inadequate management of urban sanitation systems, aggravated by the appalling state of sanitation in low-income informal settlements.
Gauteng Premier Mbhazima Shilowa said that, "to the extent possible and within our competence, we must draft policies and legislation that will give effect to the internationally-accepted principle that the polluter must pay".
Metcalfe said the environmental issues facing Gauteng are being dealt with in several ways, including waste management.
"Work is being undertaken to promote recycling, waste reduction and re-use, and a strategy for waste minimisation is being prepared.
"In addition, with the Danish government, work is being undertaken to improve the medical waste-management system; in the course of this work, issues related to incineration are being tackled." An air-quality management strategy for the province is also being undertaken in co-operation with the government of Denmark and local authorities.