Enviroserv Waste Management (Pty) Ltd (Enviroserv) conducts a waste management business involving collection of pre-classified solid waste from clients and taking it to landfill sites. At the landfill sites, cells are constructed through excavation and installation of subsoil and drainage systems. Hazardous solid waste is treated within the cells with chemicals to remove hazardous compounds. The waste undergoes decomposition and biodegradation within the cells, producing leachate (contaminated fluid) which is collected at the bottom of the cells through a drainage system and pumped to storage for further treatment. The remaining solid waste is stored indefinitely in the cells with 30-year monitoring. Enviroserv claimed depreciation allowances of R48,947,694.61 for 2015 and R41,306,206.93 for 2016 at rates of 40% and 20% respectively under s 12C(1)(a) of the Income Tax Act 58 of 1962, treating the cells as plant used directly in a process of manufacture or similar process. The Commissioner disallowed the claims, treating the cells as waste disposal assets under s 37B of the ITA, allowing only 5% per year depreciation. The Commissioner also levied an understatement penalty of 25% (later reduced to 15%) for failure to declare interest income of R25,910,000 due from a Ugandan subsidiary.