Exploring the Potential of Bioaugmentation in Sanitary Leachate Treatment for Improved Resource Recovery

ABSTRACT Sanitary landfill leachate contains a complex mixture of organic and industrial contaminants that pose significant risks to surface water quality and associated ecosystems. In this study, an in situ aerobic bio‐augmentation approach using indigenous bacterial strains was evaluated for the treatment of stabilized, mature‐like sanitary leachate characterized by a low BOD/COD ratio (< 0.2). Three native bacterial isolates were screened for their metabolic competence and applied under optimized conditions to assess reductions in key pollution indicators, including organic load, phenolics, nitrogenous compounds, and dissolved solids. The treatment resulted in substantial and consistent improvement in leachate quality, with overall removal efficiencies exceeding 80% for the major pollutant groups and compliance with surface discharge standards within the treatment period. Microbial growth showed a strong association with contaminant attenuation, and the overall leachate pollution index decreased markedly, confirming process effectiveness. Toxicological assessment using the AMES assay further indicated the absence of mutagenic potential in the treated effluent. Collectively, the results demonstrate that indigenous microbial bio‐augmentation offers an effective and scalable strategy for sanitary landfill leachate remediation and supports its potential application in sustainable leachate management and wastewater recycling frameworks.