The ruling against Exxon in a suit brought by Environment Texas and the Sierra Club found that the oil giant failed to update emissions-reductions technology at its Baytown, Texas refining and chemical plant.
In their suit, the groups alleged the plant illegally released more than 10 million pounds of pollutants between 2005 and 2013, while Exxon gained more than $14 million in economic benefits.
"Today's decision sends a resounding message that it will not pay to pollute Texas," Neil Carman, clean air program director for the Sierra Club's Lone Star Chapter, said in a statement. "We will not stand idly by when polluters put our health and safety at risk."
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