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Industrial Safety

DuPont to pay $3.1 million penalty for Texas accident

Methyl mercaptan release killed four workers at La Porte site in 2014

by Jeff Johnson, special to C&EN
July 31, 2018

Photo of DuPont's La Porte plant in Texas.
Credit: CSB
Four workers died from exposure to methyl mercaptan at this DuPont plant in La Porte, Texas, in 2014.

DuPont will pay a $3.1 million civil penalty under an agreement with the U.S. Environmental Protection Agency and Department of Justice for violations of EPA’s risk management program (RMP) provisions. The violations led to an accident that killed four workers in Texas in late 2014.

The accident occurred when nearly 11,000 kg of methyl mercaptan were released at a pesticide manufacturing unit at DuPont’s La Porte plant. Because of a series of maintenance errors, a jerry-rigged piping system transferred the flammable and toxic compound to plant areas where it should not have been. Two unsuspecting workers died when they attempted to clear a vent that they didn’t realize contained methyl mercaptan; two others died when coming to their aid.

According to EPA’s complaint, DuPont’s actions violated 22 separate provisions of the Clean Air Act’s RMP. The alleged violations include failing to develop and implement written operating procedures, adequately implement management of change procedures, and implement safe work practices. The citations also include alleged violations of mechanical integrity regulations.

The accident resulted in DuPont’s inclusion in the Occupational Safety & Health Administration’s (OSHA’s) Severe Violator Enforcement Program. OSHA uses that program to concentrate inspections on employers who have “demonstrated indifference toward creating a safe and healthy workplace by committing willful or repeated violations, and/or failing to abate known hazards,” OSHA says. OSHA also fined DuPont $106,000 for workplace safety violations.

The Chemical Safety & Hazard Investigation Board also investigated the accident and made several major recommendations to improve production safety. In 2016, however, DuPont chose to permanently shut down the unit, which manufactured methomyl, a carbamate insecticide marketed by DuPont as Lannate.

“DuPont cooperated fully with the investigations, and believes that the settlement is a reasonable resolution,” the company said in a statement. “While the company does not accept or agree with many of the government’s allegations, we will work collaboratively to improve our process safety practices.”

The RMP provisions had been slated for an update by the Obama Administration in the wake of an ammonium nitrate explosion at a Texas farm warehouse in 2013. A two-year examination of safety regulations resulted in tougher RMP provisions, but the final regulation was withdrawn under the Trump administration by former EPA head Scott Pruitt. EPA has since proposed new revisions to the program.


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