Definition: Secondary waste (or treatment residues)
Waste from secondary sources, i.e. waste generated in a process that is known as a waste treatment operation. Includes residual materials originating from recovery and disposal operations, such as incineration and composting residues.
N.B.: In accordance with the definition of waste, waste from sewage treatment (i.e. sewage sludge) is considered as primary waste.
Joint OECD/Eurostat Questionnaire 2002 on the State of the Environment, section on Waste