NEW DELHI: The groundwater near the city’s three landfill sites at Bhalswa, Ghazipur and Okhla is highly contaminated with the level of total dissolved solid (TDS), chlorine and hardness being higher than the desired drinking water limit.
Calcium and sulfate were also found to be higher than the desired limit.
This was revealed in a report by Delhi Pollution Control Committee (DPCC), which had collected samples from 4-5 locations near each landfill site in July last year.
Experts said unsegregated waste at the landfill sites leaching into the soil was contaminating the groundwater.
Priti Banthia Mahesh, chief programme coordinator of the NGO Toxics Link, said, “All types of waste are dumped at landfill sites.
The unsegregated waste, including toxic materials, releases chemicals and it leaches into the soil and contaminates the groundwater.” “The Solid Waste Management Rules state that all sources of waste should be segregated at source.
However, segregation at the household level is not happening and there is little option of separating it at a later stage.
The presence of toxic materials at landfill sites will have an impact in and around the area,” added Mahesh.
Shashank Shekhar, professor, department of geology, Delhi University, said, “These landfill sites are very old dumping grounds and were not scientifically designed.
In due course, the leachate enters the groundwater and starts polluting it, which is occurring at all these sites.” Suggesting proper remedial measures to stop the pollution load from travelling to far off areas where groundwater was currently being extracted for drinking purposes, Shekhar said, “Some reports have shown that landfill sites are polluting the groundwater, but the time has come for us to look for remedial solutions on what should be done to prevent it.” The DPCC report states that the desired TDS limit for drinking water is 500 mg/l, but it was 5,280 mg/l at Bhalswa, the highest among all three landfill sites.
The TDS level was recorded at 2,350 mg/l at Bhalswa Janta Colony and 3,330 mg/l at Bhalswa Dairy.
The TDS limit was more than double the desired limit at three locations near Ghazipur landfill site, while the chlorine level was more than 1,500 mg/l at two sites.
The level of chlorine was 1,625 mg/l near the Ghazipur entry gate against the desired limit of 250 mg/l.
Similarly, the chlorine level was above 900 mg/l at three locations near Okhla landfill site.
The report further stated that hardness through CaCO3 should not be more than 300 mg/l, but it was three times higher at Okhla.
The calcium level was the highest in an area near Okhla at 280 mg/l against the desired limit of 75 mg/l.
Calcium was higher than the desired limit at four sites each near Ghazipur and Bhalswa.