CHENNAI: Residents of Sastri Nagar and surrounding areas at Moolakadai near Madhavaram complain of groundwater pollution allegedly caused by tannery units located nearby. They say ever since the leather industry was set up 40 years ago, water obtained from bore wells is contaminated as an oily layer forms on top. Also, the water is black sometimes.
Locals said water from the bore wells appeared to be normal when drawn, but later after storing it overnight, an oily layer forms on top. Experts in the field said if effluents were not properly treated, there is a large possibility for the shallow aquifer to get contaminated over the years.
In 1997 the estate commissioned a common plant to treat 4.5 lakh litres of effluent daily. But, residents alleged that before the plant was set-up effluent waste was let into a small makeshift pond near the tanneries, which directly affected the groundwater table. “Around 30 years ago, technology for safe disposal of effluent waste was not available. As they let effluents drain into the pond for close to a decade, water table has been affected. Before they installed the pipe to Kodungaiyur treatment plant, they were letting the waste to drain into Kodungaiyur canal nearby,” said K Sadasivam, a resident.
The estate which has 15 leather tanneries was closed down by pollution control board for expanding their treatment plant capacity without prior approval. Members from the estate said that tanneries were allowed to open again in November 2018 and have been given six months to refurbish the treatment plant.
Four years ago, solid waste from the tanneries was burnt in open grounds behind the estate and after residents complained to authorities, this activity was stopped. P K Thanigavel, a resident said solid waste in the form of leftover leather hides were burnt at night a few years ago. “Around 12-1 am, the entire area used to stink because of this. After I informed the fire and rescue services and the pollution control board, this was finally stopped. But the quality of water has been the same for years now. Because there is no water even at 80 ft, people have switched to buying water from tankers, hence have forgotten this problem,” he said.
Another resident, Govindan V said quality of water from borewells has deteriorated. Water gas become unfit for drinking.
A member from the management wing of the estate said that only prior to 1990, effluents from the tanneries were buried underground and after the Supreme Court order banning this they had switched to using treatment plants. “Last year metro water had laid the pipe to its Kodungaiyur STP and we have been sending the effluents after treatment there. Allegations made by the residents are false and baseless. Every month officials from the state and central pollution control board inspect the tanneries,” said a member from the estate.
Officials from Tamil Nadu Pollution Control Board, Ambattur wing, were not reachable for comment despite repeated attempts.