Social life cycle assessment of integrated municipal solid waste management scenarios: a case study of Pakistan
摘要
This study presents a comprehensive Social Life Cycle Assessment (S-LCA) of integrated municipal solid waste management scenarios (IMSWMS) in Pakistan, an unexplored dimension in current literature. The social performance of IMSWMS was evaluated across six stakeholder groups, alongside its feasibility in relation to consumer preferences and practices.
MethodsThe S-LCA guidelines of UNEP (2020), aligned with ISO 14075, 14040, and 14044, were applied to assess five waste management options (WMOs): open dumping and sanitary landfill (publicly managed), composting, material recovery facility (MRF), and pelleting (Public-Private Partnership (PPP)-managed). Individual WMO scores were aggregated into IMSWMS results using the Reference Scale Approach, while the functional unit was defined as 1 metric ton of municipal solid waste (MSW). Inventory data covering 29 subcategories and 55 indicators were collected through facility visits, interviews, literature review, and observation. Social performance was assessed on a 1–5 scale to aid aggregation. Hotspot analysis was based on working hours and non-compliance indicators. Interpretation included conclusions, limitations, and scenario analysis.
Results and discussionPelleting achieved the highest social score (38.9), followed by MRF (38.7), composting (32.8), sanitary landfill (30.5), and dumpsite (24.1), with IMSWMS scores reflecting these contributions. Management mode was critical: PPPs outperformed across most stakeholder categories but exhibited worker-related shortcomings, whereas public entities demonstrated stronger labour compliance. Notable variation existed within WMOs under the same entity. Pelleting outperformed others due to skilled employment, while composting and MRF reflected informal-sector characteristics. Sanitary landfill scored higher than dumpsite mainly due to international donor involvement. WMOs’ inherent nature and consumer practices also shaped social performance. Hotspots included transportation for public WMOs, and collection and end-of-life management for PPPs. Key issues included worker deficiencies and child labour in PPPs, community impacts, and outdated machinery in public WMOs. Scenario analysis confirmed the decisive role of worker rights in social sustainability.
Conclusions and recommendationsIMSWMS social performance depends on both technology and institutional arrangements. Pelleting, MRF, composting, and sanitary landfill emerged as socially sustainable in the local context despite PPP’s worker-related shortcomings. Consumer behavior is critical for PPP-managed WMOs, particularly composting. Policy recommendations include the adoption of socially sustainable WMOs; implementation of PPPs with strict oversight of worker rights by the control authority; mitigation of fire and animal hazards at WMOs; strengthened community engagement; legislation for source segregation and prevention of open burning; and expansion of door-to-door collection to maximize waste capture and reduce informal interventions.