All 337 tonnes of waste of the now defunct Union Carbide factory in Bhopal has been burnt to ashes at a disposal plant in Pithampur, nearly six months after being brought to the unit, an official said on Monday.

While 30 tons of the waste was burnt earlier during three trials at the plant, the remaining 307 tons was incinerated between May 5 and the intervening night of June 29-30, the State Pollution Control Board official said, marking the end of a dark chapter of the 1984 Bhopal gas tragedy.

The waste disposal at the plant in Dhar district's Pithampur industrial area was undertaken following directives of the Madhya Pradesh High Court.

The highly poisonous methyl isocyanate gas leaked from the Union Carbide factory in Bhopal on the intervening night of December 2 and 3, 1984, causing one of the biggest industrial disasters in the world. At least 5,479 persons were killed and thousands were maimed.

The process of burning 307 tonnes of the factory waste at the disposal plant operated by a private company in Pithampur began around 7.45 pm on May 5 and ended on the intervening night of June 29-30 at 1 am, State Pollution Control Board's regional officer Srinivas Dwivedi told PTI.

It was incinerated at a maximum rate of 270 kg per hour under the supervision of technical experts of the Central Pollution Control Board and the State Pollution Control Board, following the High Court's directive issued on March 27, he said.

During the waste disposal, the emission of different gases and particles from the Pithampur plant was monitored on a real-time basis by an online mechanism and all the emissions were found to be within the standard limits, the official said.

"We have no information about any adverse effect on the health of people living in the surrounding areas during the incineration of the waste," he said.

According to Dwivedi, the ash and other residue left after burning the total 337 tons of waste were being safely packed in sacks and kept in a leak-proof storage shed of the plant.

Special landfill cells were being constructed as per the scientific process to bury the residue (waste leftovers) in the ground, and this work is expected to be completed by November, he said.

"If everything goes well, these residue will also be disposed of by December. Before this, the residue will be treated scientifically so that their burial does not cause any harm to the environment," the official said.

The waste was transported from Bhopal to the plant in Pithampur, about 250 km from the state capital, on January 2.

Initially, 30 tonnes of waste was burnt at the plant during three trials.

After this, citing the analysis report, the state government told the HC that during the trials conducted at the rates of 135 kg per hour, 180 kg per hour and 270 kg per hour, the emissions were found to be within the prescribed standards.

According to the state government, the waste from the Union Carbide factory includes soil from the premises of the closed unit, reactor residue, Sevin (pesticide) residue, naphthal residue and "semi-processed" residue.

Scientific evidence shows that the effect of Sevin and naphthal chemicals in this waste has already become "almost negligible", as per the State Pollution Control Board.

There was no presence of methyl isocyanate gas in the waste and it also did not contain any radioactive particles, it said.

Published on June 30, 2025