Williams Cos., Others Violated Pollution Standards, Suit Says

Williams Cos. Inc. and eight other companies failed to comply with air pollution standards at natural gas processing plants in seven different states, including on Native American reservations, the US alleged Thursday in Colorado federal court.

The companies’ failure to comply with leak detection and repair regulations and permit requirements have caused excess emissions of volatile organic compounds, a precursor to ground level ozone—or smog—which can cause adverse effects on human health and the environment.

Some of the facilities also emit benzene and other hazardous air pollutants that can cause cancer and other serious diseases, the US said.

The suit, ...