INVESTIGATING THE EFFECTS OF LEACHATE ON WATER QUALITY: A REVIEW

Landfill leachate is a complex and highly polluted wastewater that poses a significant threat to water quality, particularly in regions adjacent to landfills and industrial waste disposal sites. This by-product of waste decomposition typically contains a variety of pollutants including heavy metals, organic compounds, nitrogen, nutrients, inorganic salts, and other toxic substances that pose severe risks to both surface and groundwater resources. These pollutants not only compromise water but also endanger aquatic ecosystems and public health making the effective management of leachate a critical environmental challenge. This study reviews the impact of landfill leachate on water quality focusing on its composition, pollution mechanisms, and effects on aquatic systems. A desk review method was employed to analyze secondary data on leachate’s effects, focusing on recent studies published between 2019 - 2024. The findings highlight the extensive degradation of water quality caused by leachate, evidenced by alterations in pH, elevated chemical oxygen demand (COD) and biological oxygen demand (BOD), and the presence of persistent pollutants such as lead, cadmium, and other heavy metals. These contaminants bioaccumulate in organisms, disrupt aquatic ecosystems, and pose significant health risks to humans. Additionally, elevated nutrient levels in leachate contribute to eutrophication, leading to algal blooms, oxygen depletion, and further harm to aquatic life. The study also identifies the limitations of existing mitigation strategies, including physical, chemical, and biological treatments. While these approaches demonstrate varying degrees of effectiveness, challenges such as scalability, high costs, and regional implementation gaps hinder their practical application. This review underscores the pressing need for advanced and integrated treatment technologies that are both cost-effective and sustainable. By addressing these challenges, such technologies can mitigate the environmental and public health risks posed by leachate and ensure the protection of water resources. Furthermore, the study emphasizes the importance of robust management strategies and policy interventions to regulate leachate generation and improve treatment processes. Overall, this research provides valuable insights into the impacts of leachate on water quality and offers a foundation for future studies aimed at developing innovative solutions for this persistent environmental problem.