CHICAGO (AFP) – BP agreed to pay a record 50.6 million dollar fine for safety violations at its troubled Texas City refinery, officials said in a settlement which could deepen the energy giant's legal woes.

The company is already liable for billions in fines and compensation payouts in the wake of the massive oil spill unleashed in the Gulf of Mexico after a deadly explosion sank the BP-leased Deepwater Horizon drilling rig in April.

BP is also currently on criminal probation following a 373 million dollar plea deal reached in 2007 over a series of probes into an oil pipeline leak in Alaska, price fixing in the propane gas market and a deadly 2005 explosion at the Texas City refinery.

Lawyers representing some of the 15 workers killed and 170 injured in the Texas City blast are hoping that BP's probation will be revoked now that it has admitted to repeated failures to meet safety standards.

BP was initially fined 21 million dollars after the Occupational Safety and Health Administration (OSHA) determined that BP failed to adequately protect its workers ahead of the 2005 blast.

BP invested about a billion dollars on safety upgrades, but was hit with the 50.6 million dollar fine after inspectors determined in 2009 that BP still had not met its commitments.

Those findings should have been enough to trigger a default of the plea deal, said Texas attorney Brent Coon, who represents many of the victims of the 2005 blast.

Coon hopes BP's admission of guilt will force the Department of Justice to revoke probation and reopen the case to additional fines and possibly action against executives who chose to violate environmental and safety laws.

BP has already paid an estimated one to two billion in civil penalties for people hurt or killed in the blast and a record 50 million dollar criminal fine for environmental damage.

But Coon said those fines has little impact on BP's deep pockets and the Deepwater Horizon disaster proves they have not learned their lesson.

"They have a very sad and checkered past with respect to disrespecting our environmental and safety laws," Coon told AFP.

"They cut corners wherever they can. It's a bad habit of theirs and it needs to be broken."

A spokeswoman for the Department of Justice declined to comment on what impact the settlement could have on BP's probation or how this admission might affect the potentially criminal investigation into BP's role in the Deepwater Horizon disaster.

BP did not return a request for comment.

The settlement comes days after the state of Texas sued BP for the mass release of pollutants after a fire at the Texas City refinery earlier this year.

BP is accused of illegally releasing approximately 500,000 pounds of harmful air pollutants over the course of 40 days after a compressor caught fire due to poor maintenance.

BP could have avoided releasing the pollutants by idling two units until repairs were complete but instead prioritized "profits over environmental compliance," Texas Attorney General Greg Abbott said.

BP also agreed Thursday to spend 500 million dollars to improve safety conditions at the Texas City refinery and allow inspectors "unprecedented" access.

"This agreement achieves our goal of protecting workers at the refinery and ensuring that critical safety upgrades are made as quickly as possible," said Secretary of Labor Hilda Solis.

The settlement does not impact ongoing litigation over the 30 million fine imposed for 439 new "willful violations" discovered in the 2009 inspection, the Labor Department said.

"It is perfectly within BP's means to make that facility safe," OSHA Deputy Assistant Secretary Jordan Barab said in a conference call.

The settlement "commits them to a schedule to address those issues and it provides OSHA with an unprecedented level of oversight to make sure they do what they're supposed to do," he added.

The Texas City facility is BP's largest refinery and has a feed capacity of approximately 460,000 barrels of crude oil per day. It processes a wide range of petroleum products, including gasoline, heavy fuel oil and sulfuric acid.

Along with another BP facility in Toledo, Ohio, the refinery accounts for 97 percent of all flagrant violations found in the US refining industry by inspectors over the past three years, according to a report released in May by the Center for Public Integrity.