Seven years after a deadly explosion at an oil refinery in Texas City, BP Plc has agreed to pay another $13 million to settle fines over safety violations revealed in the aftermath of the tragedy. The explosion left 15 workers dead and 170 others injured. It occurred when a cloud of volatile hydrocarbon vapor ignited around portable work trailers after being released by an octane-boosting unit during a restart. An investigation completed in 2009 uncovered a rash of safety violations and the government announced it was seeking $87.4 million in fines against the British company. BP a year later settled for $50.6 million to settle most of the violations. It recently agreed to settle most of the outstanding violations for a $13 million fine, according to news reports. Additionally, BP will face civil action over the explosion and has reportedly set aside more than $2 billion to settle lawsuits. Get more information about >workplace injuries and oil refinery lawsuits.