Toxic leak from Bandhwari landfill threatens Aravalis ecosystem

Gurgaon: Leachate samples collected from the Aravalis just outside the Bandhwari landfill contain toxic substances and chemicals, significantly exceeding the permissible limits.
The samples, collected on Oct 3, were tested to determine if untreated leachate was being discharged into the delicate ecosystem of the Aravalis, the Haryana State Pollution Control Board (HSPCB) has said.
The report, released on Friday, revealed that several contaminants — including biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), chloride, ammoniacal nitrogen and fluoride — were alarmingly high. BOD levels at three sites outside the landfill were recorded at 580 mg/l, 190 mg/l and 650 mg/l, while the maximum permissible limit is 30 mg/l. Elevated BOD levels indicate bacterial contamination in the water.
Similarly, COD results were reported at 4,160 mg/l, 1,120 mg/l and 4,640 mg/l, significantly surpassing the standard limit of 250 mg/l, rendering the water quality detrimental to both fauna and flora.
Chloride levels were measured at 2,498 mg/l and 2,019 mg/l at two sites, which is approximately 21 times higher than the standard limit of 1,000 mg/l, making the water unsuitable for human consumption. The tests were conducted after a group of environmentalists lodged a complaint to HSPCB that the toxic liquid has been seeping into the groundwater from the Bandhwari landfill.
BOD is a measure of the oxygen required for bacteria to decompose organic components present in water, while COD is an indication of the chemicals in it.
According to the Central Pollution Control Board (CPCB), BOD and COD in a river or waterbody should be less than 30 mg/l and 250 mg/l, respectively.
TSS were also on the higher side — 270 mg/l, 820 mg/ and 750 mg/l — against the prescribed limit of 100 mg/l.
Environmentalists, meanwhile, pointed out that the pollution board didn't carry out sample collection in Aug and Sept.
"No samples are being collected by HSPCB Gurgaon for testing despite continuous spillage of lakhs of litre of leachate in Aravalis forest at Bandhwari landfill and reduced number of parameters. Examination of the content of heavy metals was not carried out. This is a cause for concern," green activist Vaishali Chandra Rana, who lodged a complaint with HSPCB, said.
"For the last several months, HSPCB has been omitting checking certain parameters or metals in the samples collected on at least three occasions. This lackadaisical or malfeasant attitude will only give a clean chit to MCG, which is getting away with contaminating the groundwater and surface water bodies of not only Bandhwari village, but also of the nearby four other villages and surrounding areas. In all probability, the contamination has further expanded to a radius of 20kms or more, since CPCB and NEERI last conducted tests five years ago," she added.
Responding to complaints that all parameters were not checked by the board, an HSPCB official told TOI that this month they will collect samples again and all parameters will be tested to get a clearer picture.
"We have analysed samples for nickel, lead, copper, mercury and zinc but they were within the permissible limit," an official said.