Sustainability assessment in waste management: An exploratory study of the social perspective in waste-to-energy cases

In the present world, rapid industrialization and extensive use of resources have led to an unprecedented increase in waste volumes. Industries seeking to produce more to satisfy the upsurge demand while exploiting the potential provided by advancements in technology contribute to this. This situation is leading to fast-approaching expiration date for natural resources, which calls for immediate intervention, sustainable practices, and proper waste disposal strategies. As pillars to sustainability, not only the environmental and economic aspects should be considered, the social domain is also very important to take into account. For the particular case of the waste-toenergy (WtE) technologies, the social domain entails several concerns that have never been thoroughly and representatively appraised, a clear understanding of the reasons behind this being missing. Thus, the purpose of this work is to conduct a literature review on social assessments related to the thermal conversion of wastes. Then, distinct methodologies already used for the social aspects in other areas were compared to the achieved results to better frame them and potentially suggest a workflow for this type of assessment in the WtE sector. The aim is to identify and address knowledge gaps, in order to facilitate a comprehensive evaluation of the current context surrounding this controversial topic. The main findings indicate a lack of consistent reporting practices for social life cycle assessment (S-LCA) implementation, the UNEP/SETAC approach appearing as the most commonly used. Social concerns primarily focus on employment, human health, accessibility, safety, and odorrelated issues. Knowledge gaps persist, including the need for a better understanding of the interrelation between dimensions, the absence of concise and binding legislation, low sector engagement, discrimination issues, inconsistency in sensitivity analysis, and a lack of objectivity. Based on the literature review, it can be concluded that while WtE techniques have the potential to contribute to a more sustainable and resilient society, there are social concerns that must be addressed. The review highlights the importance of conducting comprehensive social assessments in the context of thermal waste conversion. By filling knowledge gaps and considering the social implications of these techniques, a more informed evaluation can be conducted, leading to better decisionmaking and the development of more sustainable waste management strategies. This effort should be tightly connected to the sustainability efforts and goals in place, such as the ones preconized by the European Commission and the United Nations.