The Tamil Nadu Pollution Control Board (TNPCB) issued closure orders to 18 leather tanneries linked to the Common Effluent Treatment Plant (CETP) at the Second Phase of the SIDCO Industrial Estate in Ranipet, on Saturday.
According to the district environmental engineer Kamaraj, the tanneries have been asked to immediately stop production as the CETP run by the SIPCOT, SIDCO Phase II Entrepreneurs Finished Leather Effluent Treatment Company Limited, to which these tanneries have been attached to, was not able to achieve the zero liquid discharge norms as required by the TNPCB despite several warnings.
In a monthly meeting at the Collectorate, farmers belonging to this region also complained that the CETP was dumping effluents into the Palar River. Following this, Collector P Sankar directed the TNPCB here to initiate action against the tanneries.
Kamaraj said that an official survey conducted in the area two weeks ago revealed that the CETP was not able to achieve zero liquid discharge. Many of the manholes carrying effluents were not maintained properly leading to leakage on the way to the CETP.
The issue was brought up at the TNPCB headquarters in Chennai, which issued closure orders to the 18 tanneries on Saturday.
The CETP has been designed with a capacity to treat around 11 lakh litres of effluent per day whereas the plant was processing only around 4 lakh litres per day as out of a total of 35 tanneries proposed to be linked to the unit, only 18 were linked while other units were yet to begin operations.
The CETP, which commenced operation in 1995, has a reverse osmosis (RO) system, evaporator for salt recovery in addition to other treatment procedures, Kamaraj said. While the RO system was functioning properly and was able to recover around 75 per cent of the good water from the effluents, the CETP was facing problems with the salt recovery process.