HOUSTON - The largest U.S. oil refinery violated federal air pollution laws thousands of times during the past five years, releasing 10 million pounds of illegal pollution, including cancer-causing toxins, without facing proper fines or being forced to fix equipment, environmental groups claim.
Exxon Mobil Corp., which owns the refinery, is the latest target of Sierra Club and Environment Texas, which recently forced Shell into a $5.8 million settlement over its Clean Air Act violations and has filed a lawsuit against Chevron Phillips.
The environmental groups have not yet sued Exxon but have notified the Irving-based company, the Environmental Protection Agency and the Texas Commission on Environmental Quality of plans do so - a requirement under the Clean Air Act.
Among other complaints, the groups' notices accuse Exxon of violating emissions limits on sulfur dioxide, one of the components of acid rain; hydrogen sulfide, a toxic, flammable gas characterized by a rotten-egg smell; cancer-causing agents such as benzene and butadiene; carbon monoxide; and the smog-causing agent nitrogen oxide.
Exxon confirmed in a statement Wednesday that it had received a notice of the groups' intent to sue. The oil giant said it had reduced benzene emissions by 70 percent between 1990 and 2008, as well as significantly reducing other pollutants in the past decade.