The information, which included the fact that BP managers deferred a repair on the unit less than two weeks before the accident, came in a report released Wednesday by the U.S. Chemical Safety and Hazard Investigation Board. The report also said BP officials knew about frequent malfunctions of the unit for five years prior to the explosion but failed to properly investigate, according to the Chronicle.

Based on the report, Tom Sansonetti, former U.S. assistant attorney general for environment and natural resources, predicted that investigators for both OSHA and the EPA would refer the case to the Department of Justice. He said the case would likely be handled by lawyers who work for the Environment and Natural Resources Division, or ENRD, which Sansonetti ran until he returned to private practice in April.

A referral does not mean that charges will necessarily be filed. Justice Department lawyers are likely to focus on how much BP officials knew about the problems with the unit before it exploded.

BP declined comment on any possible Justice Department review, according to the Chronicle.

Ronnie Chappell, a BP spokesman, said, "We are responding and cooperating with OSHA, CSB, and agencies that have expressed interest in the incident."

For the last year, the Justice Department's environmental crimes lawyers have begun to tackle more workplace death cases, in part by using a provision in the U.S. Clean Air Act that says that any person who knowingly or negligently "releases into the ambient air any hazardous air pollutant listed ... and who at the time negligently places another person in imminent danger of death or serious bodily injury shall, upon conviction, be punished."

Possible penalties include stiff fines or even imprisonment — up to one year for negligent endangerment and up to 15 years for knowing endangerment.