Characterization of Leachate and Assessment of the Leachate Pollution Index – A Study of the Controlled Landfill in Fez

The rapid increase in municipal solid waste in developing areas, as demonstrated by the Fez landfill, has led to the production of leachate with alarmingly high levels of pollutants, highlighting the urgent need for comprehensive analysis and advanced treatment methods. This study uncovered exceptionally high concentrations of organic and inorganic substances, as well as heavy metals in the leachate, with chemical oxygen demand (COD) reaching 57,100 mg/L, biochemical oxygen demand (BOD₅) at 39.400 mg/L, and a significant presence of iron (Fe) at 1,370 mg/L, underscoring the extreme contamination levels. Importantly, this research introduced a notable contribu - tion to the field by calculating a leachate pollution index (LPI) of 88.8, a figure considerably exceeding the limits considered safe for environmental discharge. The results of the current study complement the already existing information about the critical environmental threat posed by the leachate, emphasizing the necessity for extensive treatment prior to release into the environment. The study insights are crucial for developing effective strategies to reduce the risks to aquatic ecosystems and public health, as well as for guiding policy and practice in waste management in developing regions.