How to map industrial waste metabolism at a geographical level? A proposal for a composite indicator

Waste overproduction is a relevant issue in industrialised countries. Most empirical analyses investigate the problem using household consumption and urban waste generation data to identify behavioural patterns for policy design. However, industrial production and its geographical distribution significantly contribute to territorial waste generation and require specific treatments affecting waste metabolism. This paper focuses on the supply-side of waste production in three regions, namely Lombardy, Emilia-Romagna and Veneto, which are considered to be the industrial core of Italy. To further refine the analysis, we use a sub-regional territorial unit, the local labour market area (LLMA), which depicts the local configuration of waste production and treatment and supports estimating the territorial capacity to absorb and treat industrial waste. Combining data on industrial waste production and treatment to the socio-economic features of LLMA over the period 2015-2017, a composite indicator proxying the main waste metabolism constraints is proposed, considering three main dimensions: waste items' hazardousness and quantities, their main treatment in terms of disposal or recovery, and the physical distance travelled from the manufacturing site to the waste treatment plant. Once spatialized, the obtained index provides a geographical representation of waste-based territorial weaknesses. Results show that the density of manufacturing plants, the type of industrial specialisations, and the technological characteristics of such specialisations are the primary sources of constraints to industrial waste metabolism. Overall, the paper contributes to the field by offering an original tool to assess local production systems' main sources of industrial waste vulnerability. Accordingly, the use of the index can support place-based waste policies to improve manufacturing clusters' ecological transition.