And even that is alarming: 5,300 tonnes of hazardous waste was generated in the Capital every year, according to the survey last conducted in 2007.

The state pollution control body has no information on generation of hazardous waste for 2008 and 2009, DPCC’s reply to an appeal filed by environmentalist V K Jain under the Right to Information Act reveals.

According to the reply, “The 140-page report has details on generation of hazardous waste.”

The survey in 2007 was done on the inventory of industrial units generating hazardous waste. While DPCC had given authorisation to only 1,747 units, the survey compiled data for 2,689 units.

It was also found that there are 43 illegal dumping sites in Delhi, of which 23 had waste with hazardous hexavalent chromium much beyond permissible limits.

Ravi Aggarwal of Toxic Links, an NGO engaged in municipal, hazardous and medical waste management, said, “Hexavalent chromium is very harmful since it pollutes groundwater.

“It is not just extremely difficult to remove the contents when mixed with water, it is also carcinogenic and leads to cancer.”

To manage hazardous waste effectively, the Ministry of Environment and Forests had, in 2000 and 2003, amended provisions of the Environment (Protection) Act, 1986.

Besides other parameters, the common prerequisite for any unit generating hazardous waste to be given authorisation includes a leak-proof containment system. The Act says: “Units that store hazardous waste should do so in a manner that it does not contaminate environment or groundwater due to air/rain/seepage/leakage etc.”

But 1,995 units, including 11 common effluent treatment plants (CETPs), were found generating hazardous waste by DPCC in its 2007 survey. The report says, “About 7,584 tonnes of hazardous waste is dumped in Delhi, of which 5,769 tonnes are stored in CETPs and 1,814 is being stored in rest of the industries at various industrial areas.”

In response to the RTI query, DPCC accepted that hazardous waste is stored by generator units and CETPs in their own premises. The 2007 survey compiled data for 35 industrial areas. It was found that Wazirpur Industrial Area generated the highest quantum of waste — about 790 tonnes annually. Industrial areas such as Okhla, Naraina and Samaipur were also found generating significant quantity of hazardous waste. Jain, founder of the NGO Tapas, said: “As per the Environment (Protection) Act, hazardous waste has to be disposed within 90 days of generation. But in Delhi, no one has an exact idea of how much waste is being generated. So the high quantities of hexavalent chromium found at 23 illegal sites in 2007 are still lying there.”