President Donald Trump this week ordered closures of offices at the Environmental Protection Agency that help low-income communities overwhelmed with pollution.

The order was one of dozens aimed at rescinding health and environmental protections.

It’s unclear how many positions will be cut in Chicago, but union officials estimate it may affect 20 to 30 of the roughly 1,000 EPA regional employees. Most significantly, the order ends a practice of “environmental justice” at the agency that has responded to people threatened by pollution in urban and rural areas.

Environmental justice, born in Chicago decades ago, is a movement that recognizes how poorer communities often experience more air, water and ground pollution than more affluent areas. At the EPA, environmental justice programs have zeroed in on drinking water protections as well as hazardous waste and other problems.

“Environmental justice simply means ensuring the communities most disproportionately impacted by pollution are protected,” said Nicole Cantello, president of the union representing EPA employees in Chicago and across the Midwest. “The core mission of the EPA is simple: Protecting human health and the environment.”

Cantello has previously estimated that more than 100 Chicago-area EPA workers had retired, resigned, were fired or put on administrative leave as Trump thinned the ranks. She said she had lost count and could not get clear responses from the agency’s managers on head count. EPA officials have declined to provide staffing figures for Chicago.

Under Trump, the EPA’s top brass has equated environmental justice with diversity, equity and inclusion programs, which the president has criticized.

“EPA is affirming our commitment to serve every American with equal dignity and respect,” Trump’s appointed agency administrator, Lee Zeldin, said in a statement.

The number of environmental justice employees at EPA more than doubled to around 200 under President Joe Biden, said former agency official Matthew Tejada.

About 120 of those employees were spread out across 10 regional offices, including Chicago, said Tejada, who is now a senior vice president focused on environmental health at the Natural Resources Defense Council.

“They work on water infrastructure and lead service line removals, cumulative impacts and air quality, waste and contamination cleanups like in East Chicago,” he added, referring to a large remediation program to remove lead from soil in Indiana.

On Wednesday, Zeldin went even further, announcing another 30 initiatives to roll back health and environmental protections, calling it the “biggest de-regulatory action in U.S. history.”

Those actions included a rollback of air pollution safeguards for coal-fired power plants, a planned review of fine-particle pollution rules begun under Biden and elimination of requirements aimed at curbing global warming.

“We are driving a dagger straight into the heart of the climate change religion,” Zeldin said in a video included in an agency announcement.

Gov. JB Pritzker has said that Illinois will continue working toward the goals of reducing carbon dioxide emissions that contribute to climate change. Illinois also has its own environmental protection agency reporting to Pritzker.

The state has a goal of eliminating carbon-producing fossil fuel energy by 2050, though there have been challenges to the progress on that front, including growing demand to provide power to energy-thirsty data centers across the U.S.

Coal plants have been closing in Illinois, largely because they are less economical to operate than those generating other sources of energy.

The Trump administration is considering using emergency powers to restart shuttered coal power plants, according to a report this week from Bloomberg News.