Life cycle assessment in municipal solid waste management system: a case study of Naga City, Camarines Sur [Philippines]

Cities are dynamics spatial forms of urban ecosystem and continuously emergent with highly integrative material and energy flows. Their inputs and outputs are actively influenced and developed by human society for an overall functionality. As urbanization accelerates, intensified material production and energy consumption amplifies and solid waste generation rate level. This study conducted life cycle assessment (LCA) on the municipal solid waste system of Naga City, Camarines Sur to evaluate the environmental burdens associated in each system scenario of waste collection, transport, segregation, sorting and end disposal. The reference system focuses on 20,941,027 kilograms per day, collected municipal solid wastes from households in all 27 barangays [villages] of Naga City, Camarines Sur by all 9 collection routes in year 2022. Key findings reveal landfill provisions are associated with environmental impacts exhibited by indicative input and output flows (i.e. pressure on raw materials, energy utility, and emissions). Significant contribution by immediate landfilling to environmental impacts are found in (1)Climate Change; (2)Fossil and Nuclear Energy Use; (3)Photochemical Oxidation Formation; (4)Ozone Layer Depletion; (5)Freshwater Acidification; (6)Terrestrial Acidification; (7)Freshwater Eutrophication; (8)Marine Eutrophication; (9)Ionizing Radiation; (10)Land Transformation and Occupation; and (11)Water Scarcity whereas residual landfilling with wastewater treatment facility is observed to be a substantial contributor to the Impacts on (1)Mineral Resource Use; (2)Freshwater Ecotoxicity; (3)Human Toxicity, and (4)Particulate matter Formation. Their impact pathways are accentuated by the limited and provisory system conditions that are contingent upon LGU's technical capacity and availability of infrastructure facilities. As a result, toxicants are haphazardly exposed in the direct environment and hints stern impairment of human health and ecosystem quality. Concerned city departments display proactive approach but its overall local environmental governance omits an integrated strategy centered on evidence-based monitoring and evaluation. Henceforward, the local municipal solid waste management system performance can be improved if and when a process-specific material flow accounting outline is reinforced in the standard operating procedures. Clarity and coherence in environmental management mechanisms for each progress stage should be resolved across institutional arrangements for improved operational efficiency.