KwaZulu-Natal's environment minister Narend Singh voiced renewed concern about the spate of industrial air pollution accidents in the province on Thursday, after witnessing a huge pall of black smoke south of Durban.
He spoke of "crumbling" industrial infrastructure and also appealed to residents to come forward with more information about a separate case of gaseous fumes on the Bluff and elsewhere in the city on Wednesday - an event now believed to be connected to a leaking Engen storage tank at Island View in Durban harbour.
Opening the National Association for Clean Air conference in Durban, Singh said the gathering was opportune, considering his experience on Wednesday afternoon when he saw clouds of smoke several kilometres long hanging over the Sapref refinery.
He said the Sapref incident was caused by a major power failure which forced the refinery to burn off gas vapours as a safety precaution.
Earlier the same day his officials had been unable to trace the source of several complaints from local residents about gas odours in the city.
On Thursday night it emerged that a leak on the roof of an Engen storage tank in Durban harbour had been detected. Engen apologised to residents and said the tank contained crude oil, diesel and paraffin.
Officials confirmed that firefighters sprayed foam around the tank and remained on standby while attempts were made to reposition the tank's "floating" metal roof.
Singh said a legacy of poor planning had placed Durban in a position where trade-offs had to be made almost continually between economic considerations and human welfare.
"I often wonder whether the haphazard planning of the past is now combining with obsolescence of plant and pipeline infrastructure to create new risks as the infrastructure starts crumbling."
Singh said he believed several "captains of industry" seemed to accept the need to invest in cleaner technology to reduce pollution, but he also warned that government would not hesitate to shut down industrial operations until the owners put their houses into order.