ANNOUNCEMENTS
Leachate emanating from the landfill site, can act as a toxic pollutant. Ghazipur landfill is an open dumping site, without having any liner and leachate collection system. Thus, leachate percolating through this site have an immense potential to degrade the surface and groundwater quality. Leachate with its toxic constituents collected from Ghazipur site was analyzed and compared with other Indian landfills. Parameters such as organic, inorganic and heavy metals were observed to be above leachate discharge standards. Due to the potential of leachate to contaminate environmental matrixes, leachate decolorization experiment was conducted. Through decolorization it was found that coagulation flocculation technique using FeCl3 gave better results in terms of percentage of color removal (99.7% at pH3.5), COD removal (98.6% at pH 3) and TOC removal (99.94% at pH 3.5) as compared to advanced oxidation technique using FeSO4 and H2O2. In this way, decolorization of landfill leachate can be preferred as a pre-treatment method. This study also determines the human health risk posed by Ghazipur leachate containing heavy metal constituents such as lead, chromium, cadmium and nickel. For this, Chronic Daily Intake and Cancer Risk values were estimated from the year 2003-2019. The temporal variation of cancer risk was observed in both adult as well as child. Results showed that cadmium have high risk factor of 1.06×10-4 in 2003,8.37×10-4 in 2016 and 1.02×10-4 in 2019 as compared to other heavy metals. These risk values exceeded the permissible limit of 10-6. The temporal variation in cancer risk is due to the heavy metal variation observed in each respective year. This change in metal concentration values is governed by various factors such as temperature and rainfall.
Keywords: Leachate, Decolorization, coagulation- flocculation, advanced oxidation, Chronic daily intake, cancer risk.
