(Reuters) – Friday’s announcement by the U.S. Environmental Protection Agency that they would probe Texas’ air regulator in regard to allegations of racial bias regarding rulings relating to pollution in Black neighborhoods caused by a refining waste recycler.

An agency was notified by Texas to resolve a dispute over the oversight of Oxbow Calcining’s Port Arthur plant. It produces petroleum coke with oil-refinery byproducts.

Environmental advocacy groups have claimed the state’s air-quality regulator has violated citizens’ civil rights, allowing the plant without a scrubber in order to capture sulfur dioxide. The plant produced about 22 million pounds of sulfur dioxide per year between 2016 and 2019. This is an eye- and lung irritation.

Texas Commission on Environmental Quality spokesperson said that the agency had not yet received any comment.

“I am encouraged by the response of the EPA to investigate our concerns,” said John Beard, a former Port Arthur city councilor and founder of advocacy group Port Arthur Community Action Network.

Oxbow Calcining is situated in a predominantly Black area. The group stated that 98% of those living within a radius of three miles are people of color, while 62% have lower income.