Pre-demolition audit as a tool for appropriate CDW management – a case study of a public building

Abstract

The identification of hazardous construction and demolition waste (CDW) is crucial for the appropriate and safe waste management. The pre-demolition audit is not compulsory in all EU member states, so if the control is not strict the hazardous CDW might pollute the inert fraction and create risks for human health and environment. In Bulgaria, only some industrial sites are considered as a potential source of hazardous CDW. Classification of hazards can be difficult also because the European Waste Catalogue is not specific on the hazardous CDW (with some exceptions). For example, heavy metals are among the most dangerous substances but very often remain undiscovered or underestimated. A case study of an abandoned 100-year-old public building has been performed to illustrate the importance of the pre-demolition audit. A handheld XRF analyser is used to identify contaminated materials. Samples were taken from those materials for doing leaching tests. It was proven that there was a high content of heavy metals in different paints, on internal and external walls, and fenestration. In addition to the discussion of results, some measures to separate the hazardous coatings from the recyclable masonry and wooden waste are discussed to provide higher recovery rates for the CDW.