Neutralizing Methyl Isocyanate Begins at Union Carbide Plant

As federal and state experts kept a careful watch, Union Carbide Corp. on Thursday began disposing of the last 3,000 pounds of deadly methyl isocyanate at its plant here.

Officials said the neutralization process employed by Carbide had never been used to dispose of such large quantities of the chemical, but they expressed confidence it would pose little danger.

“We believe it’s safe,” said Tim Laraway of the state Department of Natural Resources. “We’re going there to observe as a contingency. Someone will be there to oversee any emergency.”

The Institute plant, about 10 miles west of Charleston, is the only U.S. producer of methyl isocyanate, the chemical that leaked from a Carbide plant at Bhopal, India, killing more than 2,000 persons. U.S. production was halted after the disaster.

Carbide officials said Jan. 10 that all the chemical had been converted into pesticide at the plant. But state officials disclosed this week that another batch of 3,000 pounds had been discovered.

“All of the methyl isocyanate that could have been used in the production process was used,” Laraway said. “The remainder is material that they could not use in their production process because it didn’t meet their specifications.”

The chemical was being neutralized in a pollution-control device by being mixed with sodium hydroxide and water to produce dimethylurea, a non-toxic substance that was to be dumped into the Kanawha River.