Metabolisms of injustice: municipal solid-waste management and environmental equity in Barcelona's Metropolitan Region

Abstract

Environmental justice studies that focus on the management of municipal solid waste (MSW) typically examine the unequal distribution of associated health and environmental risks in minority social groups and the political processes that generate these inequalities. With the aim to complement current views on the field, in this work, we explore whether there is an issue of environmental justice in municipal systems' grade of self-sufficiency in treating the MSW that they generate and in their effort to close their material cycles. The methodology used is based on the concept of urban metabolism and is applied to 12 coastal municipalities of Barcelona's Metropolitan Region in Spain. The metabolism of the MSW flows of each system is analysed to examine (i) the system's efficiency to close its MSW cycles, corresponding to an indicator of environmental sustainability, and (ii) the MSW export and import flows, as an indicator of social sustainability. The results demonstrate a positive correlation between socioeconomic status and the externalisation of MSW treatment-related hazards. The proposed indicator proves to be an excellent tool for the evaluation of both the environmental and social performance of a system considering MSW management.

Keywords:

• municipal solid-waste management
• environmental justice
• social metabolism
• urban sustainability
• Barcelona Metropolitan Region

Acknowledgements

Financial support was provided by the Interreg IIIC SUDOE project (ECOTEC_SUDOE SOE/P2/E377). The authors thank the two anonymous reviewers for their valuable comments and suggestions.

Notes

1. Although landfill sites are traditionally generators of environmental conflicts and have low popularity in public opinion, we choose to omit these facilities from our study. In addition to the methodological restrictions mentioned above, the diversion of MSW from being landfilled is a main goal of recent MSW legislation at all administrative levels (see Section 4 for more details). Consequently, the number of landfill sites is gradually reduced and accordingly so is the relevance of landfill sites in environmental justice studies.

2. As stated in the Directive 2008/98/EC of the European Parliament and of the Council on Waste (European Commission 2008).

3. The generic term “treatment plants” that will be used from now on also includes sorting plants. Because the difference between their inputs and outputs corresponds to recovered material, we consider sorting plants as treatment plants in this methodology.

4. Following the indicator's mathematical expression (Equation (1)), this value can be equal to unity when both of the following conditions are met: (i) all of the MSW generated (G) is either directly reused (R) or treated inside the system (I_x,p) with zero outputs (O_x,p), and (ii) no fraction of the MSW generated (G) is sent to landfill (I_landf = 0) or exported (I_exp = 0).

5. For a more detailed analysis on the importance of the transport stage in a MSW-management scheme, see Fragkou et al. (2010).

6. When preparing the indicator, variables such as the percentage of people older than 65 years (retired) and the percentage of people born in a foreign country were taken into account, among others, but these variables were rejected because of their low discrimination power.

7. See Equation (1).