As the administration of US president Donald Trump continues to roll back environmental legislation passed by its predecessor, 14 states and authorities of the US capital of Washington DC are suing the Environmental Protection Agency (EPA) over its plans to dismantle national safety regulations for chemical plants.

Led by New York, the states have called on the federal appeals court in Washington to review a rule finalized by the environment agency in December 2019 that would cancel Obama era amendments aimed at improving safety and reducing the threat of accidents at chemical production plants and refineries.

The legislation Trump-appointed EPA Administrator Andrew Wheeler would remove is the Chemical Disaster Rule protecting workers and nearby residents adopted during the waning days of the Obama administration. The rule was drawn up in reaction to a 2013 explosion at a fertilizer plant at West, Texas that killed 15 people and injured more than 20 others.

That incident followed several other deadly high-profile incidents, including a 2012 refinery fire in Richmond, California, which led more than 15,000 people to seek medical attention. In drafting its new rules, the EPA said existing protections had failed to prevent more than 2,200 fires, explosions, leaks and other chemical accidents over a 10-year period.

The Obama amendments, which require plant operators to take steps to reduce the threat of toxic chemicals being released into the atmosphere, call for greater use of outside audits, closer analysis of safety technology and the imposition of stricter emergency preparedness requirements.

According to the states, many of the then-added protections have now been removed from the EPA’s latest amendments. Wheeler asserted last year that the new amendments would be adopted to reduce “unnecessary regulatory burdens” for plant operators.

This is the fourth time US environmental and safety advocates have sued the EPA over the Chemical Disaster Rule, which has never been fully implemented, due to political opposition. The first lawsuit was filed in 2017, when the since dismissed EPA director Scott Pruitt put the amendments on ice.

The second suit was filed in late December 2019 by 13 NGOs nationwide, who were subsequently joined by 12 states and the city of Philadelphia, Pennsylvania. A suit by the United Steelworkers trade union followed in early this year.

The NGOs noted that “nearly 180 million Americans live in the worst-case scenario zones” for a chemical disaster, with affected communities having disproportionately low-income and minority populations.

Speaking to journalists earlier this month, Kristen Kulinowski, interim head of the Chemical Safety Board (CSB), which was created by the US Congress to investigate major accidents and report to the EPA, said the threatened rollback “takes us in the opposite direction from where the CSB would like to see the nation going.”

The Trump administration has pledged to eliminate the Chemical Safety Board. While advocacy groups have openly criticized the agency in the past for its perceived foot dragging on accident investigations, none wants to see it eliminated.