Report: extremely high toxicology levels at Mumbai dumping ground

A study commissioned by the Brihanmumbai Municipal Corporation has shown that toxicology levels at the Deonar dumping ground in Mumbai are up to four times the permissible limits. Conducted by NETEL India Limited, the study comes against the backdrop of plans to relocate residents of Dharavi, who will be displaced due to a large redevelopment project, to the dumping ground site after clearing it. Deonar is India’s largest and oldest dumping ground, with garbage piles as high as 12-storey buildings. Several reports have already warned that settlements near the area are exposed to mercury and toxic gases. According to The Indian Express, the study commissioned by the municipal corporation analysed the levels of Biochemical Oxygen Demand, Chemical Oxygen Demand, and Total Dissolved Solids in the waste and leachate at Deonar. All three are key indicators of environmental toxicology, with high levels indicating the increase of toxins.
According to the study, the average Biochemical Oxygen Demand in the leachate was 390 milligrams per litre against a permissible limit of 100 milligrams per litre for land and 30 milligrams per litre for water. The average Chemical Oxygen Demand was 1,002 milligrams per litre against a permissible limit of 250 milligrams per litre for water. Finally, the average Total Dissolved Solids level was 6,550 milligrams per litre against a permissible limit of 2,100 milligrams per litre. The study also pointed out that between 30 and 50% of the dumping ground is filled with “inert waste”, including construction debris and non-biodegradable materials. This type of waste has a low degradation rate posing several challenges for management and disposal.