IPTU verde e gestão de resíduos: estimativa do potencial de desvio de massa e redução de emissões de GEE no contexto de Pedras de Fogo (PB) /

Abstract

The increasing generation of municipal solid waste and the structural limitations faced by small municipalities represent a significant challenge for the implementation of environmentally adequate waste management systems aligned with the guidelines of Brazil’s National Solid Waste Policy. In this context, economic policy instruments have been discussed as mechanisms capable of inducing behavioral changes and improving the efficiency of municipal waste management. This study aimed to evaluate the potential of the Green Property Tax (IPTU Verde) as an incentive instrument to promote the segregation of recyclable waste and household composting in the municipality of Pedras de Fogo, Paraíba, Brazil, as well as to estimate its effects on waste diversion from final disposal and on greenhouse gas emission mitigation. The methodology involved a systematic literature review on public policy instruments applied to municipal solid waste management and was based on prospective scenario modeling, considering demographic data, per capita waste generation, and local gravimetric composition. Methane emissions were estimated using the First-Order Decay (FOD) model, following the methodological guidelines of the Intergovernmental Panel on Climate Change (IPCC) for the waste sector. Three program adoption scenarios were simulated (10%, 25%, and 50%), allowing the assessment of the progressive impact of the policy instrument on the municipal waste management system. The results indicated a significant increase in the mass of waste diverted from landfill disposal, reaching 773.31 t·year⁻¹ in the highest adoption scenario, corresponding to a reduction of approximately 6.65% in the total waste flow sent to final disposal. In climatic terms, net emission reductions of 53.30, 133.24, and 266.48 tCO₂e·year⁻¹ were estimated for the analyzed scenarios. Sensitivity analysis indicated that biogas capture efficiency and the increase in organic waste capture are the parameters with the greatest influence on the results. The findings demonstrate that the Green Property Tax has significant potential as a local environmental governance instrument, contributing simultaneously to waste valorization, reduction of pressure on disposal systems, and mitigation of emissions associated with the waste sector.