$16 million in fines and probation related to fatal methyl mercaptan leak at La Porte, US

More than eight years after a major methyl mercaptan leak at a DuPont plant in La Porte, US, killed four employees and injured others, the company and the head of its Insecticide Business Unit (IBU) have both pleaded guilty to criminal negligence.

On 24 April, a Texas district court judge ordered DuPont to pay a $12 million (£9.6 million) penalty and serve two years of probation, during which the company must grant the US Probation Office full access to all its operating locations. Kenneth Sandel – the operations leader who was responsible for ensuring that workers understood and complied with government safety, health and environmental regulations – will also serve one year of probation.

DuPont must also make a $4 million community service payment to the US National Fish and Wildlife Foundation to fund projects that benefit air quality in and around the western shores of Galveston Bay in Texas, an area affected by the methyl mercaptan leak. In total, DuPont will have paid a more than $19 million in fines related to the fatal leak from the La Porte facility in November 2014.

The incident, which occurred when workers were trying to clear a solid mercaptan hydrate blockage in pipework after the gas was diverted into vent systems that lacked appropriate sensors, led to an explosion and release of over 10 tonnes of the highly toxic, flammable gas into the air that travelled downwind into surrounding communities.

Sandel and other DuPont employees failed to provide sufficient instructions to the oncoming shift about how to safely clear such a blockage, according to the Department of Justice (DOJ). A federally mandated safety procedure for opening valves on such a waste system was disregarded, the agency added.

DuPont and Sandel admitted to negligently releasing an extremely hazardous substance into the ambient air. The company also acknowledged negligently placing a person in imminent danger of death or serious bodily injury in violation of the federal Clean Air Act.

Separately, DuPont has been fined $99,000 for 11 violations by the US Department of Labor’s occupational safety and health administration (OSHA), and settled chemical incident prevention violations with the Environmental Protection Agency (EPA) for $3.1 million. The La Porte plant never re-opened following the incident and has since been demolished.

‘The failure to follow required chemical safety procedures at Dupont’s La Porte facility resulted in the deaths of four employees,’ said Larry Starfield, acting assistant administrator of the EPA’s Office of Enforcement and Compliance Assurance. ‘This case demonstrates the importance of holding chemical facilities accountable for implementing chemical safety requirements that are designed to protect workers and neighbouring communities,’ he added.