On Thursday DuPont announced that it will close its troubled La Porte plant, a key part of which has been shuttered since a November 2014 gas leak that killed four workers.

Officially, the chemical giant decided to shutter the plant, which in recent years employed nearly 500 workers, because of โ€œchanges in the market,โ€ like lousy business in Brazil brought on by low crop prices and tight credit. In filing with the U.S. Securities and Exchange Commission yesterday, the company also says itโ€™s closing the plant because of โ€œuncertainty regarding when the facility could be restarted and further capital expenditures required for the restart.โ€

By โ€œcapital expenditures,โ€ DuPont may be referring to the list of upgrades federal regulators called for following the leak of more than 20,000 pounds of methyl mercaptan at the La Porte plant on November 15, 2015 (the chemical attacks the nervous system before triggering death by respiratory paralysis).ย According to federal investigators, the chemical unexpectedly spewed into the third floor of the plantโ€™s pesticide unit when veteran operator Crystle Rae Wise opened a faulty valve on her early morning shift. Wise died in the accident, as did three men who rushed in to help her and other workers in the unit โ€“ Wade Baker and brothers Robert and Gilbert Tisnado.

The chemical leak further tarnished DuPontโ€™s reputation as a leader in workplace safety within the industry, a reputation thatโ€™s slowly begun to erode over the past decade as the company sought to cut costs. Still, DuPont has essentially blamed the La Porte tragedy on operator error, something federal regulators say is simply not true. Federal investigators brought in after the accident have already concluded that across-the-board failures by DuPont created a hazardous environment at the plant, endangering not only the companyโ€™s workers but also the public.

For instance, preliminary findings by the Chemical Safety Board released last fall say workers on the pesticide unit had grown accustomed to the stink of low levels of methyl mercaptan, which can be lethal in small concentrations. Any monitoring for the chemical was so poor that โ€œmultiple DuPont employees informed the CSB that odor was the primary method used to locate a methyl mercaptan leak.” Upon inspection, critical ventilation fans on the unit where the workers died were inoperable, and even if theyโ€™d worked, the ventilation system designed to purge toxic air from the building didnโ€™t even appear to operate correctly.

Then there were the huge methyl mercaptan storage tanks on site that lacked proper insulation and relief valves, which federal investigators say exposed the public to potential toxic leaks.

The CSB isnโ€™t even done with its investigation. It came to a halt last summer when regulators said they learned of DuPontโ€™s plan to restart the pesticide unit without all the upgrades needed to ensure worker and public safety. The board scrambled to come up with a list of recommendations for essential systems and fixes needed before the plant could could start up again. CSB investigators said DuPont wasnโ€™t even considering those fixes until they went public with their findings and recommendations last fall.

Back then, DuPont said it was considering those upgrades to the plant. Now, it appears the company would rather just scrap the whole thing.ย