Integrated Emission Inventory and Mitigation Strategies for Air Pollutants and Greenhouse Gases in the Waste Sector: A Case Study of Semarang City

Abstract

This study aims to develop a comprehensive inventory of air pollutants and GHG emissions from the waste sector for the 2024–2033 period and to formulate mitigation strategies aligned with Indonesia’s Nationally Determined Contribution (NDC) target of a 29% emission reduction by 2030. A mixed-method approach was applied, combining primary data from transect walk surveys across 12 representative wards with secondary datasets. Air pollutant emissions were estimated using the UNEP Atmospheric Brown Cloud (ABC) inventory method, while GHG emissions were quantified based on the IPCC (2006) Tier 2 methodology. Dispersion modeling using AERMOD was conducted to assess the contribution of waste-sector emissions to ambient air quality. Results indicate that the waste sector contributes 1.9%, 5.6%, and 1.6% to ambient concentrations of total particulate matter (TPM), NO₂, and SO₂, respectively. Under the business-as-usual scenario, GHG emissions are projected to reach 507.26 Gg CO₂eq by 2030. The implementation of integrated strategies including methane capture from Jatibarang Landfill, expansion of waste bank units and 3R-based treatment facilities, and installation of biodigester septic systems achieves a 29.67% reduction, lowering emissions to 356.78 Gg CO₂eq. These findings highlight the dominant role of landfill methane recovery and improved waste management infrastructure in emission mitigation. The proposed framework demonstrates a scalable, data-driven approach for cities to simultaneously address air pollution and climate change through integrated waste sector management.