More information, the report and a CSB video here.

Chemical rule plan creates challenge

Board investigators blamed the explosion and fire in the plant's methomyl-Larvin pesticide unit on a long string of equipment failures, management lapses, unsafe procedures and poor planning.

"This accident should never have happened," said board member John Bresland, a longtime chemical plant manager who was chairman of the CSB when the Bayer incident occurred.

In a more than two-year probe, CSB officials found that many of the accident's causes were longstanding issues that have previously been identified by the company or by federal regulators -- but still had not been corrected.

The board's 169-page report recommends the state and Kanawha County begin new chemical plant safety programs that would include regular government safety audits and requirements for new accident prevention programs by companies.

John Vorderbrueggen, the board's investigations manager, said such programs would force companies to allow government reviews before they make major changes to complex chemical-making units, a mandate that "keeps the pencil very sharp" for company and government safety planners.

"With the extra set of eyes and the extra-sharp pencil, all of the things that were overlooked would not have occurred," Vorderbrueggen said during a morning press conference at West Virginia State University's campus adjacent to the plant.

The board urged the state Department of Health and Human Resources to work with the Kanawha-Charleston Health Department to start a statewide program, citing existing legal authority for DHHR to "make inspections" and "conduct hearings" concerning "occupational and industrial health hazards."

"I believe a state and county-run program like this would go a long way to making chemical operations safer in places like the Kanawha Valley," said board Chairman Rafael Moure-Eraso. "Local jurisdictions can put together highly effective and targeted inspection and enforcement programs, funded by levies on the plants themselves."

Many of the board's findings were previously released at an April 2009 congressional hearing and in a preliminary report, both of which warned that the methomyl-Larvin explosion came dangerously close to damaging a tank of methyl isocyanate. Also known as MIC, the chemical killed thousands of people in a 1984 leak at a Union Carbide plant in Bhopal, India. Board officials and congressional investigators also previously reported that Bayer had tried to use an anti-terrorism law to keep confidential many details of the incident to avoid negative publicity and public pressure about its huge MIC stockpile.

Safety board investigators blamed the explosion on a "runaway reaction" in a 4,000-gallon tank called the "residue treater," which was used to break down methomyl into wastes that are burned in the plant powerhouse.

In their new report, board investigators said plant operators were pressured to restart the unit after a long maintenance shutdown, despite the fact that new operating instructions had not been completed, pre-startup reviews were not performed and equipment examinations not finished.

Employees were not properly trained on an entirely different computer control system, and were working large amounts of overtime under a new management structure that left shift workers without proper supervisors on site at all times.

"The deaths of the workers as a result of this accident were all the more tragic because it could have been prevented had Bayer CropScience provided adequate training, and required a comprehensive pre-startup equipment checkout and strict conformance with appropriate startup procedures," said Moure-Eraso.

In the residue treater, other materials were to be heated to a certain temperature and then a tiny amount of methomyl added for decomposition. Bayer was aware that adding too much methomyl would speed up the reaction to the point of generating heat and pressures that would spiral out of control.

But CSB investigators believe the residue treater had a heater that was too small, and therefore would not bring the unit to a high enough temperature or took too long to reach that temperature. As a result, workers regularly used -- with management's knowledge -- a workaround that deactivated at least two safety controls that prohibited the methomyl from entering the residue treater before the unit was hot enough.

"Once the chemical reaction of the highly concentrated methomyl started, it could not be stopped," Vorderbrueggen said, "and the temperature and pressure inside rose rapidly, finally causing an explosion."

Investigators warned that the explosion sent the residue treater flying across the plant, and that the vessel could have hit an MIC tank located about 75 feet away. The tank was surrounded by a steel "blast blanket," but the CSB found that the equipment provided only "marginal" protection and might not have stopped the tank from being damaged and causing an MIC release.

Board members noted that Bayer has recently announced that it will stop making, using and storing MIC as part of a corporate restructuring, and said the elimination of the chemical inventory is a positive step for the Valley.

"Any significant MIC release into the atmosphere along the Kanawha Valley could have proven deadly, and that concern has been legitimately expressed for decades in the community," Moure-Eraso said. "Bayer's decision to end pesticide production using MIC was, I understand, done for its own business reasons. But for whatever reason, the eventual elimination of this chemical will enhance safety in the Kanawha Valley, for workers and residents alike, and is a positive development in my view."

Reach Ken Ward Jr. at kw...@wvgazette.com or 304-348-1702.