Untreated Effluents From Dyeing Units
Water analysts who examined the samples of the effluents discharged into River Noyyal by dyeing units in Selvapuram and Perur area have certified that they had toxic contents exceeding the permissible level. Untreated effluents from dyeing units in Selvapuram, Perur areas are being let into the Noyyal polluting the river water as well as groundwater in the areas. Foams in different colours were seen in the river during the recent rain. Following orders from Collector V. Palanikumar, water analysts took samples of the effluents and sent them for analysis. He also directed the Revenue Divisional Officer, M. Balachandran, to inspect dyeing units, the river and initiate action against the polluting units.
Of the 41 units in the areas, power supply was disconnected to 12 units. Notices were served on the other units. The Chief Water Analysts Laboratory of the Department of Public Health and Preventive Medicine here examined the samples taken from the Common Effluent Treatment Plant (CETP Inlet and Outlet) and at the confluence of Rajavaikkal. The report stated that the samples were intense grey in colour with a black tinge and were highly turbid. The dissolved contents of the samples were extremely high ranging at 4640 mg/1 as against the permissible level of 2100 mg/1.
As per the norms of the Bureau of Indian Standards , the effluents while discharged should not contain more than 100 mg/1 suspended solids. However, the three samples had suspended solids at the rate of 550mg/1, 1,230 mg/1, 1,360 mg/1. Similarly, the chloride contents were also at the rate of 1,550 mg/1 and 2,580 mg/1 exceeding the permissible value of 1,000 mg/1.
All the three samples contained very high amount of sodium chloride increasing the salinity of receiving waters and would affect the plant life severely if used for irrigation. The BOD values, pH values and oil/grease contests of the samples were also high. High organic matter content and the continuous consumption of such water would lead to health problems.As against the permissible sodium chloride content of 60 per cent, the samples had 92 per cent.High salinity found would also harm fishes in the river, the report added.
The treated effluents showed a slight improvement over that of raw effluents with reference to the organic matter only and it was also of poor quality indicating inadequate treatment. The sample of effluents collected at the confluence of the Rajavaikkal was in no way better than the raw or treated effluents. The report concluded that the effluents were totally unfit for discharge either into water course or on to land or into sewers. Following the lab report, Mr. Palanikumar and the Tamil Nadu Pollution Control Board have ordered action against the dyeing units.
