Updated

The Justice Department has decided it won't seek criminal charges against Imperial Sugar or its executives years after explosions tore through its sugar refinery near and killed 14 workers, a federal prosecutor in Georgia said Tuesday.

U.S. Attorney Edward Tarver issued a two-page statement saying prosecutors determined at best they would be able to bring only misdemeanor charges alleging violations of industrial cleanliness standards of the federal Occupational Health and Safety Administration. There was not enough evidence that the company intentionally disregarded or was indifferent to safety requirements to even prosecute a misdemeanor case, Tarver said.

Investigators years ago determined the deadly blast Feb. 7, 2008, was caused by accumulation of sugar dust that exploded like gunpowder and said the company had been warned about dust problems before.

In addition to the 14 people killed, 36 workers suffered injuries — several of them surviving severe burns.

"I was hoping somebody would get prosecuted and go to jail over this," said Jamie Butler, who suffered burns to his face, arms and legs in the explosion. He was working at the refinery alongside his brother, Calvin Butler Jr., who died. "We just thought we were going to work on a regular day. It hurts, man."

In 2010, Texas-based Imperial Sugar settled with OSHA by agreeing to pay more than $6 million in civil fines for safety violations at the Georgia refinery as well as at its plant in Gramercy, La. The federal agency had accused Imperial Sugar of 221 safety violations. Imperial Sugar said it admitted no wrongdoing by settling the case.

Federal investigations launched after the explosion determined that Imperial Sugar had been warned about dangerous dust inside the Georgia plant as recently as 2002, and that prior warnings had been issued since as early as the 1960s. The refinery is the second-largest in the U.S. and has been operating for nearly a century.

Tarver said in his statement that OSHA's housekeeping standards would only allow for misdemeanor charges against the company — not its officers or employees — and the maximum penalty would be a $500,000 fine. He said prosecutors could find no other criminal law under which to prosecute the deaths of the sugar workers.

When it rebuilt the Georgia refinery in 2009, Imperial Sugar said it added numerous safety features. Its settlement with OSHA also required the company to maintain an improved housekeeping program, employ a full-time safety manager for the Georgia plant and undergo audits by outside safety experts for the next three years.

Based in Sugar Land, Texas, Imperial Sugar was bought by Louis Dreyfus Commodities Sugar Holdings LLC in a merger last June. A phone message and email seeking comment from the company were not immediately returned Tuesday.

John Sheptor, who was Imperial Sugar's CEO during the explosion and its aftermath, did not immediately return a phone message. Sheptor now works as a corporate leadership consultant and is based in Maryland.