It's been forty years since a Union Carbide chemical plant exposed five hundred thousand people to methyl isocyanate in Bhopal, India. Thousands were killed in the initial event, thousands more died from complications months or years later, and at least a hundred thousand were permanently injured.
The cause of the incident was the introduction of water to a methyl isocyanate storage tank. This caused a runaway reaction, overpressurising the tank from 14 to 280 kPa over the course of two hours, at which point the tank cracked - but even with atmospheric escape of the gas, pressure continued to increase to nearly 400 kPa - at which point the gauge could no longer give an accurate reading.
After roughly 30 tonnes of gas escaped, employees triggered the plant's alarm system - which was originally designed to alert both workers in the plant and the people in the surrounding city. Company policy mandated that they not alarm the populace about "inconsequential" leakages, so the two alarms had been decoupled by the time of the release. For nearly an hour and a half, the plant's management continued to tell authorities that everything was fine and they had no idea what had happened. Hospital staff had to guess what gas was causing the symptoms. No shelter in place order was given; the public siren remained silent for an hour and a half.
Union Carbide had identified 61 hazards at the Bhopal plant in a 1982 audit, but never followed up on the inspection. Mere months before the incident, UCC discussed the possibility of a methyl isocyanate reaction similar to what occurred in Bhopal at one of their West Virginia plants - however, the report and its predictions were never forwarded to the Bhopal plant, despite the similar design and process.
The Union Carbide Corporation asserts that the incident was caused by sabotage performed by a disgruntled worker. They claim that workers conspired with the Indian government to hide evidence of sabotage in order to blame the company, claiming that the safety systems were sufficient to prevent the incident without human intervention.
On the night of the incident, the tank's monitoring equipment had been malfunctioning for years, reduced to a single manually operated backup. Management had shut off refrigeration of the tank, keeping it at more than 15 degrees Celsius above the recommended temperature. The emergency flare and gas scrubbers had been out of order for months - and even if they had been active, they had insufficient capacity. Deluge guns - a type of pressurised water cannon intended to dissolve escaping gas - lacked enough pressure to even reach the gas cloud.
No motive for the alleged sabotage was suggested.
Warren Anderson, CEO of Union Carbide, refused to answer homicide charges by the Indian government, with the US government denying repeated requests for extradition. He died in 2014, months before the thirtieth anniversary of the disaster in Bhopal.
Union Carbide have divested their stake in their Indian subsidiary UCIL, and refuse to fund any efforts to clean up the abandoned site, insisting that the fault lied with UCIL management and the alleged saboteur. The company paid $470 million dollars to the Indian government - which worked out to a cost of 43 cents per share of the company. Union Carbide's annual earnings were $4.88 per share after the Bhopal settlement.
The 2012 Global Intelligence Files leak revealed that Union Carbide's current owner, Dow Chemical, had employed the surveillance firm Stratfor to monitor activists seeking compensation for the Bhopal disaster.
Dow responded to the email leak that they were "required to take appropriate action to protect their people and safeguard their facilities" - an attitude that seems to have been very lacking in 1984.
