The federal suit filed in the US District Court in San Francisco Wednesday alleged the exports would affect numerous communities near the mines, ports and railways – and that the bank had failed to consider this, or conduct the required review of the environmental impacts of its financing under the National Environmental Policy Act.

The bank provided a $90 million loan guarantee in May last year to Xcoal Energy & Resources to ship coal from ports in Baltimore, MD and Norfolk, VA, to Asian and European markets.

The Chesapeake Climate Action Network, Center for International Environmental Law, Friends of the Earth, Pacific Environment, Sierra Club, and West Virginia Highlands Conservancy filed the action. They are represented by Earthjustice.

"Ex-Im Bank turned a blind eye to the toxic coal dust, heavy train traffic and disruptive noise that our members living near ports and railways experience on a daily basis," senior general counsel Diana Dascalu-Joffe said.

"People on the frontlines of the US coal export boom deserve to know the risks and to have a say over whether their tax dollars finance it."

While US coal consumption has gradually declined over the past 10 years, exports have risen, the groups said in a statement.

They said they were not just concerned about potential health impacts on communities from the transport of coal to ports, but that burning coal overseas would increase global warming.

The plaintiffs are asking the court to order Ex-Im Bank to prepare an environmental impact statement for the Xcoal loan guarantee.

If successful, the case could also require the agency to conduct environmental reviews of future coal export projects it considers financing.

"The Export-Import Bank's continued investment in coal undermines the spirit of President Obama's recently-announced climate action plan. The plan is a clear commitment to end U.S. public support for overseas coal," said associate director of the Sierra Club International Climate and Energy Program Justin Guay.

The National Mining Association called the case "a nuisance lawsuit replete with hyperbole" and based on sweeping, inaccurate and undocumented claims.

Spokeswoman Nancy Gravatt told the Associated Press the intent appeared to be to frighten the public and cause the industry economic harm.

Railroads have been hauling coal for more than 100 years without harming public health or the environment, she said, and technology had reduced coal dust loss by at least 85%.

"They grossly exaggerate what 'science' has said about coal's environmental impact while wholly ignoring its beneficial impact on hundreds of millions of people in the developed world suffering from energy poverty as documented by the World Health Organization," Gravatt said.

An Export-Import Bank spokesman said it was against policy to comment on pending litigation.

Earlier in the month, the bank rejected the financing of US exports to a coal-fired power plant in Vietnam.