The second respondent owned property on which it operated a sawmilling business (previously owned and operated by the first respondent since 1991). The operation involved disposing of large quantities of sawdust and wood chips by burning them in a 'Rheese burner'. In 1968, the whole Republic was declared a 'controlled area' under the Atmospheric Pollution Prevention Act 45 of 1965, requiring registration certificates for 'scheduled processes' including wood-burning processes generating noxious or offensive gases. The respondent applied for a registration certificate in December 1991. After prolonged correspondence, a provisional 8-month certificate was issued in January 1993 with conditions, on the understanding the Rheese burner would be replaced within three years. The Department of Health received numerous complaints from neighbouring property owners about smoke emissions. The provisional certificate expired and was not extended. In February 1994, inspectors visited and the respondent undertook to replace the burner by end of 1995. The Department informed the respondent in March 1994 that no registration certificate would be issued and the incineration must stop immediately. The Minister applied for an interdict in June 1994 to restrain the respondent from continuing to operate the Rheese burner without a valid registration certificate.