By Erwin Seba
HOUSTON (Reuters) - A U.S. judge on Thursday approved BP <:BP.LO:>Plc's agreement to pay $50 million -- the largest U.S. criminal environmental fine ever -- after pleading guilty to charges stemming from a 2005 explosion that killed 15 workers at a Texas refinery.
BP's plea agreement had been held up after families of victims complained the penalty was too lenient for BP, pointing out that regulators found that the company sacrificed safety at the plant to cut costs.
But U.S. District Court Judge Lee Rosenthal approved the agreement in which BP's U.S. unit pleaded guilty to criminal charges stemming from the blast, which also injured 180 workers at the Texas City refinery, 40 miles southeast of Houston.
"It is the opinion of this court the plea should be accepted," Rosenthal said.
The plea deal also requires the U.S. unit of London-based BP to serve three years on probation.
The ruling brings an end to nearly four years of legal battles between survivors and BP over the March 23, 2005, explosion at BP's Texas City refinery, the third largest in the United States.
"We deeply regret the harm that was caused by this terrible tragedy," said BP spokesman Daren Beaudo. "We take very seriously the commitments we've made as part of the plea agreement."
The deal, negotiated in 2007 by federal prosecutors in Houston and BP, was held up after the U.S. Fifth Circuit Court of Appeals in New Orleans ruled that it violated the rights of relatives of the dead and blast survivors to be consulted by prosecutors prior to the agreement.
But Rosenthal said she did not have the power to change the plea deal, only to approve or dismiss it as a whole.
Specifically BP pleaded guilty to failure to comply with federal environmental law to prevent accidental releases of regulated substances.
Survivors have argued the fine was a paltry sum to BP, which reported a net profit of $21.2 billion for 2008.
Eva Rowe, whose parents both died in the explosion, criticized the plea deal and said BP officials should have been punished.
"It just doesn't make sense," Rowe said outside the courtroom, fighting back tears. "It seems so unfair that someone isn't punished and they just get to write a check."
A U.S. Chemical Safety Board investigation of the blast showed BP had allowed refinery process safety and reliability to dangerously erode at the Texas City refinery in the years leading up the explosion in part due to cost cutting efforts after BP bought the refinery in a 1998 merger with Amoco.
"We will continue the work we're doing at Texas City and our other facilities to reduce risk, improve plant integrity and environmental compliance to prevent something like this from happening again," BP's Beaudo said.
Hundreds of lawsuits stemming from the explosion forced BP to set aside $2.1 billion to pay claims. No single case was decided by a jury as BP was able to reach settlements.
Among those suing BP were relatives of those killed, severely injured blast survivors, and people who suffered some kind of damage from the explosion that shook buildings up to five miles away.
(Reporting by Erwin Seba, Editing by Chris Baltimore and David Gregorio)