GONZALES — An unexpected and unprecedented chemical chain reaction at the Westlake Chemical Corp. complex in Ascension Parish released enough heat to breach a metal-walled column used to make vinyl chloride monomer, touching off a March 22 plant fire, the company said.
In a 14-page letter to environmental regulators, Andrew Kenner, vice president of manufacturing for Houston-based Westlake, wrote the reaction was not the result of operator error and could not have been anticipated, therefore the company should not be subject to Louisiana Department of Environmental Quality penalties.
The initial column conditions setting the stage for the fire-causing chain reaction remain under investigation, including whether key pipeline valves were functioning, Kenner wrote.
The company has hired an outside expert to test valves controlling chlorine flow.
The resulting blaze shot a plume of smoke high into the air over Westlake’s Geismar Vinyls Complex off La. 30 early on March 22.
The fire forced residents inside for a few hours, closed the Mississippi River and highways for hours to a few days and shut down for a month and a half the complex that makes precursors for common household plastics.
The letter says the release and column fire occurred at 8:03 a.m. March 22, never involved an explosion and was out by 8:20 a.m. Kenner’s letter says the fire involved a far smaller chemical release than initially reported, primarily steam. A separate fire continued past 8:20 a.m. in an ethylene line.
Westlake spokesman Dave Hansen said in an email Friday the ethylene fire was extinguished at about 9 a.m. March 22.
Initial reports from authorities the day of the fire and later indicated an explosion occurred and the fire lasted longer in the column.
The VCM column, which was knocked askew and has been replaced since the fire, had been shut on March 19 for routine maintenance before the ill-fated startup sequence.
The March 22 incident, one of two detailed in the letter, has prompted two state District Court lawsuits in Ascension Parish filed by residents alleging health and psychological effects from the fire and chemical release.
Investigations by DEQ and the federal Occupational Safety and Health Administration are under way.
State Police also cited the company for not timely notifying a hazardous materials hotline, a State Police report says. Westlake has stated it notified State Police after several attempts and is working to resolve the matter.
Kenner says in the letter that testing by third-party consultants and various agencies shows chemical releases on March 22 and on the second, separate incident on May 9 did not cause any tangible environmental or health concerns.
Four contractors went to the hospital after the May 9 incident, in which a power outage led to a small release of VCM, but the hospital released the contractors to return to their jobs after a few hours without treatment, the letter says.
Kenner wrote that the release on May 9 also could not have been anticipated and is asking DEQ for no penalties.
Kenner’s letter asserts the series of events inside the VCM column on March 22, five separate elements in all, have never happened in the 30-year history of that column at the Geismar plant.
“Indeed, an incident such as occurred on March 22 has never been reported at any other VCM facility in the history of chemical operations in the United States,” he wrote.
Kenner sent the May 31 letter to DEQ Assistant Secretary Cheryl Nolan at her request to address the question of her agency’s possible penalties for both incidents.
Jean Kelly, DEQ spokeswoman, said Thursday that agency officials have reviewed Kenner’s letter and other reports.
“It’s still under investigation, and they don’t talk about it while they are investigating,” she said.
Kenner’s letter says that the unexpected levels of chlorine and hydrochloric acid in the VCM column during startup began the chain of events with other chemicals in the column.
Chlorine can react with ethylene dichloride, which is normally in the column at startup, to form hydrochloric acid.
Chlorine and hydrochloric acid reacted with the column wall, catalyzing chemical reactions with column contents and raising temperatures that caused a “tear” in its wall, the letter says.
When the column’s pressurized contents hit the air, the fire started immediately.
Kenner’s letter says that valves controlling the flow of chlorine and hydrochloric acid into the column were shut at the time of the fire but adds that the company is trying to determine if they were properly functioning.
Hansen said Friday that chlorine valve testing is ongoing by Russell Ogle, principal engineer with Exponent Failure Analysis Associates of Chicago.
But Hansen said that Westlake has finished remedial work.
Kenner’s letter says that the remedial action includes adding redundant valves and other safety measures to prevent the same kind of chain reaction from happening again.
Westlake has removed the two state court lawsuits to U.S. District Court in Baton Rouge and they have been consolidated before Chief District Judge Brian A. Jackson. Plaintiffs’ attorneys want the case moved back to state court, filings say.
Elizabeth Todd, OSHA spokeswoman, said an investigation also has been opened into the May 9 incident at Westlake.
Westlake and DEQ officials have described a March 28 estimate of the chemicals released on March 22 as the maximum possible. The estimate initially included a list of 15 chemicals, including amounts of potentially toxic VCM, chlorine and hydrochloric acid.
The second March 22 fire in the ethylene line released steam, water, carbon dioxide and ash or soot, Kenner’s letter says.