The contamination of soil and groundwater at the Union Carbide plant in Bhopal has nothing to do with the 1984 gas leak disaster, according to a study released on Thursday by the National Environmental Engineering Research Institute. Instead, the toxic wastes were dumped over a much longer period between 1969 and 1984.

NEERI's presentation to the Group of Ministers last month made it clear that “Union Carbide's Bhopal plant was a polluter long before the 1984 gas leak disaster,” as reported by The Hindu. In its final report, NEERI has re-emphasised this fact, correcting common perceptions.

“During the study, it appeared that there is a general misunderstanding among the public as well as various agencies and organisations that the MIC gas tragedy in 1984 also resulted in contamination of soil and groundwater in and around UCIL premises,” says the final NEERI report. “However, it may be made clear that contamination of soil and groundwater in and around the UCIL premises is solely due to dumping of the above mentioned wastes during 1969 to 1984, and the MIC gas tragedy has no relevance to it.”

The report says that “the solid, semi-solid, liquid and tarry wastes generated during the manufacture of pesticides and associated chemicals were dumped by UCIL within their premises from 1969 to 1984,” which raises the question of how regulators turned a blind eye for 15 years.

NEERI's recommendations in the report echo what the agency told the GoM, and was subsequently accepted by the Union Cabinet. As immediate measures, it recommended that the incinerable wastes be burnt at the Pithampur facility, while the 1.1 million tonnes of contaminated soil be buried in a landfill at the site itself. The five contaminated wells should be sealed and the company premises fenced and secured properly to prevent unauthorised access, said the report. In the long term, the contaminated groundwater needs to be pumped and treated.

It put the total cost of soil remediation at Rs. 78 crore to Rs. 117 crore, while the capital cost for the pump and treat unit was pegged in the range of Rs. 25 lakh to Rs. 30 lakh. The operating and maintenance cost of the unit would range between Rs. 10 lakh and Rs. 15 lakh per annum, including the cost of activated carbon and its disposal.

The Indian Institute of Chemical Technology has also framed the tender for the detoxification, decommissioning and dismantling of the Union Carbide plant itself.