The management of waste plays a pivotal role in achieving the Sustainable Development Goals (SDGs) set by the United Nations through both direct and indirect linkages. Directly, waste management issues are addressed in four SDGs (6, 11, 12, 14), while landfilling issues are only mentioned in SDG 6 reflecting water quality in connection with waste dumping. However, inadequate management and disposal of waste pose environmental, health and safety risks; thereby undermining more SDGs. Indirectly, waste management and landfilling influence various SDGs ranging from 4 to all 17 SDGs depending on the literature reference.Although not directly addressed in SDG 13 (Climate action), the waste sector contributes to climate change, with the biggest share of greenhouse gases emitted from landfills and waste dumps. According to the latest assessment report by the IPCC (Intergovernmental Panel on Climate Change), waste management—and thereby mainly landfills—are responsible for 64 Mt of CH₄ per year worldwide.A waste-related assessment of the IPCC report series from 1990 to 2023 revealed a paradigm shift in the covered waste management strategies, transitioning from conventional technical disposal methods towards holistic approaches that align with the principles of sustainability encapsulated in the SDGs. The focus in the reports moves upwards the “waste management hierarchy”, fostering circular economy. Indirectly, this leads to seemingly less focus on landfills and waste dumps despite their high share of greenhouse gas emissions and particularly their strong representation in low/lower middle-income countries, which is still expected to increase during the next years.

This study examines methane (CH₄) emission factors from biogas and wastewater treatment plants, based on primary and secondary data collected from 109 facilities. Primary emission data were measured at 19 facilities representing prevalent plant configurations across Europe. Statistical analysis highlights two categorical variables, namely primary feedstock and plant size, expressed as CH₄ production (≤250 kgh^-1: small and medium-sized plants, >250 kgh^-1: large plants), each of which has a significant impact on whole-site CH₄ emissions. Additionally, digestate storage (gastight vs. not-gastight) has a meaningful effect when considering CH₄ production as a continuous variable in the statistical analysis. Our results indicate that wastewater treatment plants have the highest average CH₄ losses (7.0 % of CH₄ produced, n = 31 or 0.10 kgpopulation equivalent(PE)^-1yr^-1, n = 28), followed by manure-based plants (3.7 %, n = 49), biowaste treatment facilities (2.8 %, n = 11) and energy crop-processing plants (1.9 %, n = 14). Furthermore, small and medium-sized plants have elevated emissions (5.6 %, n = 67) compared to larger counterparts (2.2 %, n = 42), primarily attributed to the absence of gastight digestate storage. Emissions tend to be lower with gastight digestate storage (2.7 %, n = 61) than not-gastight storage options (6.2 %, n = 48). Emission factors were determined for normal operating conditions, with a further investigation into other-than-normal operating conditions revealing temporal or constant emission peaks in eight out of 19 facilities. These peaks, suggesting potential areas for targeted mitigation strategies, were attributed to pressure relief valves, flare ignition problems and major leakages.