| Abstract | This study assessed atmospheric emissions, including air pollutants, greenhouse gases (GHGs), and short-lived climate forcers (SLCFs), from municipal solid waste (MSW) management in Takeo Province, Cambodia. An emission inventory was developed for the baseline period (2013–2025) and projected to 2035 under three alternative scenarios: Scenario 1, focused on engineered landfilling without landfill gas (LFG) capture; Scenario 2, focused on composting; and Scenario 3, focused on incineration with a reduced landfill share. All scenarios were evaluated with and without air pollution control (APC) for the incineration component, producing six modelled trajectories. A Multi-Criteria Decision Analysis (MCDA) using 14 criteria was also conducted, drawing on input from 15 Cambodian waste management and environmental engineering experts at both provincial and national levels. The baseline analysis showed that approximately 46% of waste remained uncollected in 2025, with 57% of that fraction openly burned. Total emissions increased from 448,481 to 752,726 tCO₂-eq/year between 2013 and 2025, a rise of 68%. Black carbon (BC), driven almost entirely by open burning, accounted for 64% of total CO₂-eq in 2025, while CH₄ from unmanaged landfilling rose approximately 16-fold over the same period. In 2026, the baseline reached 767,885 tCO₂-eq/year. All three scenarios with emission controls achieved notable reductions: Scenario 1 by 42.3% (442,765 tCO₂-eq/year), Scenario 2 by 36.8% (485,648 tCO₂-eq/year), and Scenario 3 with APC by 37.1% (482,664 tCO₂-eq/year). Scenario 3 without APC was the only variant that worsened emissions, increasing total CO₂- eq by 42.4% due to uncontrolled incineration. By 2035, Scenario 2 achieved the greatest reduction of 40.0%, reaching 528,390 tCO₂-eq/year against a growing baseline of 880,374 tCO₂-eq/year. The MCDA ranked engineered landfilling first (69.25), followed by composting (60.36) and incineration (39.22). Landfilling scored highest on the three most important criteria: safety of public health (5.21), capital cost (5.52), and operation and maintenance cost (4.98). Incineration ranked last due to low scores on all three criteria and limited local technical capacity. The study concluded that expanding waste collection to reduce open burning is the most important near-term step for lowering emissions, regardless of treatment technology. A combined landfill–composting approach was identified as the most suitable strategy for Takeo Province, in line with Cambodia\'s NDC 3.0 targets. Long term improvement will depend on building institutional capacity and securing sustainable financing for waste infrastructure. |
