CHENNAI: The southern bench of the National Green Tribunal (NGT) has admitted an application alleging that the 1,500 MW Vallur Thermal Power Project, operated by NTPC Tamil Nadu Energy Company Limited (NTECL), is discharging hot effluent directly into the Kosasthalaiyar river and its backwaters in violation of environmental and CRZ clearances. The tribunal has issued notices to the concerned authorities and the plant operator.
The application was filed by Ennore-based fisherman Selvaraj Duraiswamy against the Union Ministry of Environment, Forest and Climate Change (MoEFCC), Tamil Nadu Pollution Control Board (TNPCB), Tamil Nadu Coastal Zone Management Authority and NTECL. The plea comes against the backdrop of a reported fish kill in the Kosasthalaiyar on August 15 and 16. A community field study cited in the application recorded a maximum water temperature of 40.8°C about 585 metres from the alleged discharge point on August 9.
According to the petition, the environmental clearance issued in 2007 stipulated a re-circulating cooling-water system with natural draft cooling towers. It also permitted treated effluent to be conveyed to the existing NCTPS lagoon and discharged along with circulating water, with the temperature difference capped at 5°C above ambient.
The petitioner has alleged that the mandated cooling towers and pipeline intended to carry effluent to the NCTPS outlet were not constructed. Instead, he claimed, effluent is being discharged through a canal adjoining the plant and eventually reaches the Kosasthalaiyar. The application further alleged that effluent from different streams, including the coal stockyard and desalination plant, is discharged through the outfall.
The petitioner also pointed to a 2018 MoEFCC inspection, which, according to him, recorded the absence of the mandated cooling towers and discharge of effluent outside the plant premises.
The application claimed that satellite imagery and photographs submitted before the tribunal show the alleged discharge. The petitioner has sought directions to stop discharge into the Kosasthalaiyar, its backwaters and adjoining creek, ensure compliance with environmental clearances and provide an appropriate marine outfall after necessary studies.
