In European legislation, waste is classified either as hazardous or non-hazardous. Hazardous waste is a waste that due to its (intrinsic) chemical or other properties poses a risk to the environment and/or human health. The legislation was revised in 2014 in order to align it with the chemicals regulation, the CLP Regulation. The classification is primarily based on the European List of Waste (2014/955/EU). In some cases a particular type of waste on the list can be either hazardous or non-hazardous depending on the specific properties of the waste and in these cases the waste status has to be assessed based on its hazardous properties, typically by evaluation of composition data based on worst case scenario.
One of the hazardous properties “ecotoxicity (HP14)” is critical especial for wastes containing harmful metals. Some large waste streams, especially MSWI bottom ashes are likely to be subjected to further testing, because the metal concentrations (e.g. copper and zinc in MSWI bottom ash) exceed the concentration limits when applying the calculation formula given in the legislation. However, in practice it is not clear how to evaluate the properties based on testing. The test methods given in chemical legislation are often not suitable or practical, because these have been developed for pure chemicals.
Common rules for waste classification on a practical level are needed, especially for waste streams that are shipped or traded from one country to another. Some countries have developed own schemes for assessment, but there is a need for a harmonised assessment scheme. Testing procedures that are not specified may lead to different results and interpretation of results.
This paper will assess potential methods or tools for waste classification and also lessons learned in testing. The focus is especially on testing of large recyclable waste streams.
