DuPont will pay a fine of $1.275 million and spend an estimated $2.3 million more to settle claims by U.S. officials that the global chemical conglomerate failed to prevent toxic releases of hazardous substances in West Virginia that killed at least one man, environmental regulators said on Wednesday.

E.I. du Pont de Nemours and Co reached the settlement with the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Justice in a case about eight alleged releases of harmful levels of hazardous substances between May 2006 and January 2010 from a DuPont facility in Belle, West Virginia, the EPA said.

Several of the releases posed "significant risk to people" and a nearby river, the government said in statement announcing the settlement. One DuPont worker died after exposure to a toxic gas released due to DuPont’s "failure to comply with industry accident prevention procedures," the EPA said.

The problems came to light in January 2010 when plant operators discovered that more than 2,000 pounds of methyl chloride had been leaking, and employees had failed to respond to alarms triggered by the release.

~In addition to the $1.275 million penalty, DuPont is to take corrective actions to prevent future releases. The company has estimated it will spend $2.276 million to complete required improvements. The company said it already has spent nearly $7 million to comply with an EPA order for corrective measures.

DuPont expressed deep "regret" for the death of its employee in a statement issued Wednesday and pledged tight controls.

"We remain committed to meeting all regulatory requirements and operating at the highest standards for protection of our employees, contractors, community and the environment," the company said.

The EPA said that inspections of DuPont's records identified five incidents in which the company released harmful quantities of hazardous substances and then did not report the releases in a timely manner. The largest of these was the release of 80 tons of methanol into the Kanawha River in West Virginia on Sept. 21, 2010.