Material Flow Analysis (MFA) and waste characterizations for formal and informal performance indicators in Tandil, Argentina: Decision-making implications.

In cities, the achievement of waste-related legal requirements and the main drivers of Integrated Sustainable Waste Management (ISWM) need adequate indicators and adaptable-to-case tools and strategies. In this work, we combine Material Flow Analysis (MFA) and waste characterizations to develop a mass balance table to design, calculate and analyse indicators related to the formal and informal waste sub-circuits of Tandil, a medium-sized city of the Buenos Aires province (Argentina). Results show that global recovery is very low (2.3% ± 0.16) and mainly driven by the Informal Recovery Sector (IRS). Also, the IRS strategy is more effective, recovering 40% ± 8.0 of its targeted materials from non-household sources. Regarding each material recovery performance, results show significant differences. For paper and board, recovery exceeds 20%. For HDPE, Tetra brik and Ferrous Metals are lower than 1%. In the case of PET and Glass, 9.6 and 9.0% of what is generated in households is recovered, respectively. However, the global recovery rate of each material is different: 2.9% ± 0.4 for PET and 5.5% ± 1.4 for Glass. Our research show that strategies in place are insufficient regarding legislation in force. Even a hypothetically 100% effectiveness in them will account only for 20.9% ± 2.1 of global recovery. Addressing organic waste, therefore, is imperative. Considering the current province law provision of final disposal diversion, accounting for the work of the IRS is key because they recover more waste than the official strategy. Regarding open dumps eradication, we estimate that up to 17% of generated waste is incorrectly final disposed through private skips illegally dumped. A tracking system for skips could avoid this situation.