HOUSTON — The largest US oil refinery released more than 8 million pounds of illegal pollution in the past five years, violating the Clean Air Act thousands of times, a lawsuit filed by Texas environmental groups alleges.
The lawsuit against ExxonMobil is the latest by the Sierra Club and Environment Texas as part of their campaign to rein in what they call illegal emissions by dozens of refineries and chemical plants on the Texas Gulf Coast.
They have reached multimillion-dollar, out-of-court settlements with Shell and
ExxonMobil denied the allegations. In the past five years, the
And since 2003, Exxon has invested nearly $1.3 billion in the Baytown facility to improve environmental performance, the company added.
Texas has more oil refineries, chemical plants, and coal-fired power plants that any other state and is the nation’s leader in producing greenhouse gases. The state produces more than 20 percent of the nation’s oil; one-third of the country’s gas is refined on the Texas Gulf Coast.
The federal lawsuit, filed in Houston, accuses Exxon of violating emission limits on sulfur dioxide, a component of acid rain; hydrogen sulfide, a toxic, flammable gas characterized by a rotten-egg smell; such cancer-causing agents as benzene and butadiene; carbon monoxide; and the smog-causing agent nitrogen oxide.
It says “emissions events’’ are usually caused by equipment breakdowns and malfunctions.
The legal maneuvers are part of the broader accusations by the environmental groups and the Environmental Protection Agency that Texas’s state regulators are not properly monitoring and enforcing federal emissions standards.
State regulators say their rules decrease pollution, but are not so stringent that it becomes too expensive to operate in the state.![]()



