A geospatial approach for addressing long-term solid waste management issues: Extracting value from waste

Mauritius faces significant solid waste management challenges owing to its growing population, limited waste management infrastructures, and increasingly limited land space. Selection of new solid waste management sites is currently limited by a siloed approach, where previous geospatial studies have focused on identifying new suitable landfill sites rather than taking a holistic approach to identify different solid waste management options. Recognising the limitations of space and resources on Mauritius as a closed-loop system, a multi-criteria model incorporating socio-technical, economic, environmental, legal, and climatological factors is implemented to identify propitious sites for the construction of a combined landfill and composting facility equipped with an LFG recovery system at Melrose, and an incineration plant near Seizieme Mille. About 128.0 GWh, representing 4% of the electricity requirement of the country may be met from the incineration facility while the landfill gas recovery system has a technical potential of 67 GWh, representing 2% of the national electricity requirement, using equivalent solid waste streams. The profitability of generating electricity from waste-to-energy facilities, attributed to the lower marginal costs of incineration ($70/MWh) and landfill gas ($119/MWh) as compared to fossil fuels has the potential to spawn long-term environmental benefits, which stems from the avoided emissions due to the reduction in fossil fuel combustion for electricity generation. Emphasis laid on material recovery through the composting of organic wastes to dampen synthetic fertilizer use, and the recycling of certain solid waste categories would ensure a more sustainable and liveable society based on the principle of extracting value from wastes. •A multi-criteria GIS-based model is set up to explore waste management scenarios.•Optimum sites for an incineration and a combined landfill and composting plant are revealed.•The marginal cost of waste-to-energy is compared to fossil fuel electricity generation.•The technical potentials achieved through incineration and LFG recovery are revealed.•Avenues for recycling and industrial symbiosis relevant to an island state are discussed.