Effluent treatment plants have not proved effective

Tishya Chatterjee , member secretary, Andhra Pradesh Pollution Control Board (APPCB) spoke to Manish Tiwari on the presence of persistent organic pollutants and metals in groundwater at two prominent industrial areas of the state

 
Published: Tuesday 31 August 1999

What is the status of groundwater in the industrial areas of Andhra Pradesh?
Studies conducted by the State Groundwater Authority and National Geophysics Research Institute, Hyderabad, in the Bolaram and Patancheru areas, Medak district, have shown groundwater to be contaminated by high levels of toxic organics, chlorides, sulphates and arsenic. In some areas, the contamination level is so high that even remedial measures will not improve the situation.

What is polluting the groundwater?
Over the years, industries in the state have illegally dumped effluents and hazardous wastes in the open. Now they are gradually becoming more conscious and many of them have even installed multiple-effect evaporators which dry up the effluents and solidifies the residue. These wastes are then packed in high density poly ethylene ( hdpe) bags. The industries are awaiting a ruling from the ap High Court on the setting up of a solid waste safe disposal facility. Here, industries hire tankers, which supply potable water during the day, for dumping effluents at night. These effluents contain a chemical oxygen demand ( cod ) as high as 150,000 mg/l and a total dissolved solids ( tds ) level of 80,000 mg/l, which cannot be broken down by any treatment plant.

How do you plan to tackle the problem?
It is a well known fact that the Common Effluent Treatment Plants ( cetp s) have failed to effectively treat effluents of the bulk drug industry because of the huge quantity of toxic organic salts and inorganics they receive for which they are not designed. Today, there is some move to segregate inorganic and toxic organic waste at source so that once the effluents reach the cetp s, they can be treated effectively. Segregation needs to be improved as cetps are receiving highly diluted effluents, ensuring wastage of fresh water.

For this, the appcb is planning to construct a Treatment, Storage and Disposal Facility ( tsdf ) in Hyderabad where solidified waste from these industries can be stored safely. We have already arranged for 81 hectares of land for the landfill site. Ironically, a case was filed in the ap High Court, alleging that the appcb did not conduct an Environment Impact Assessment ( eia ) on the proposed tsdf before starting work.

The truth is we have conducted comprehensive documentation and study before beginning the work. Not only did we conduct an eia , the appcb also worked out a detailed environmental management plan for the purpose. Unless we provide such a facility and encourage the private sector to invest in waste management, industries will have no alternative but to dump the waste in hdpe bags on their premises.

Which are the companies that are pumping effluents into groundwater?
At the Nakkavagu sub-basin, the primary source of contamination is the cetp at Patancheru. When effluents were analysed for heavy metals, strontium was observed in the effluents of I T W Signode (I) Limited, Rudraram village, Medak district. This unit produces steel strips. This industry has since rectified the problem. During the scrutiny of material balance and analysis reports of effluents of some industries in 1998, the presence of salt, toxic organics, particularly, arsenic, cadmium and nickel, came to light. We have caught several industries dumping untreated effluents in the open or emptying it in nearby streams.

When did the APPCB first notice this?
The presence of high concentrations of heavy metals in Nakkavagu sub-basin's groundwater was observed when the appcb began monitoring groundwater in 1997-98.

What action did the APPCB take?
The appcb constituted a monitoring committee to find out details about the operations and material balance of each of the polluting industries in this sub-basin. It has also instructed the industries to segregate and vaporise in forced evaporators all inorganic and heavy metal effluents.

Are you satisfied with the efforts of the industries?
We are not yet satisfied. Our efforts have been to encourage the use of multiple-effect evaporators to reduce the intensity and extent of liquid pollution. However, due to the High Court stay order on the construction of the tsdf in Hyderabad, even solid waste is piling up. Industries discharging more than 40 kld (kilo litres per day) of effluents have gone in for recovery of solvents and raw materials before sending inorganic effluents to cetp s. It will take at least two years of continued pressure before we can achieve discharge standards at the cetps .

What is the solution to the problem?
The only effective way to deal with deliberate environmental crimes committed by industries is to close them down as a punitive measure, and not as an administrative tool as we are doing today. Prosecution (penalties) under the Acts sound very prohibitive, but the litigation procedures take too long, certainly long enough to take away the bite in the law.

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