Union Pacific Railroad won’t be able to escape a lawsuit filed by Houston residents who claim the company failed to warn them about cancer-causing soil and groundwater contaminants, after a request for the Texas Supreme Court to intervene was denied Friday.

The company, which has come under fire after state and local investigations uncovered toxic chemicals in the Kashmere Gardens and Fifth Ward neighborhoods, argued claims against them should be tossed on free speech grounds. Lawyers for the company previously filed a motion with a lower court under the Texas Citizens Participation Act, which was denied.

Union Pacific unsuccessfully appealed that decision to an intermediate court, and then finally to the state Supreme Court, where the justices declined to take up the case.

A spokesperson from Union Pacific said the company was disappointed by the Texas Supreme Court’s decision, and was reviewing the company’s options going forward. Union Pacific has previously said it has worked on cleaning up the site over the past three decades.

In a statement, Mayor Sylvester Turner commended the Supreme Court’s decision to reject Union Pacific’s petition.

“The City, in collaboration with the County and others, will continue to advocate on behalf of the many families in the Kashmere Gardens area that have experienced major, if not fatal, health challenges,” Turner said. “UP cannot ignore its responsibilities to these families.”

Harris County Attorney Christian Menefee also applauded the decision on Twitter.

A Union Pacific railyard near the historically Black and Hispanic community is the site of a former industrial facility where wooden railroad ties were treated with a chemical called creosote, a likely human carcinogen. The neighborhood was named a cancer cluster in 2019.

Last week, the Houston Health Department announced it discovered levels of dioxin in a soil sample near the site. Dioxin is a highly toxin chemical also likely to cause cancer.

Critics of the company have called the site a “textbook case of environmental racism.”