Roberts added that, "Unfortunately, some environmental groups didn't like the result and filed for an injunction to block the settlement.

"The federal judge blocked the settlement and scheduled a hearing on the injunction for September," Roberts said.

"If the company concludes that it will never be allowed to mine those reserves and withdraws the equipment from the mine, those miners may never go back to work," he said.

Chief U.S. District Judge Charles Haden II has not issued an injunction to block the settlement. Coal companies have gone to court to challenge the settlement agreement.

Environmentalists challenged an expansion permit for Arch Coal Inc.'s Dal-Tex mine after the U.S. Army Corps of Engineers exempted it from the additional scrutiny called for in the settlement.

In response, Haden issued a preliminary injunction that halted the expansion until a full trial in the case, scheduled for September. Less than a week later, Arch Coal announced it would close Dal-Tex and lay off nearly 400 miners who work there.

Doug Gibson, a press spokesman for the mine workers, said the "settlement" that Roberts referred to wasn't the lawsuit settlement, but instead was federal agencies' decision to exempt the Dal-Tex permit from additional scrutiny.

In testimony before a U.S. Senate committee, Roberts criticized efforts by environmentalists to curb global warming, reduce air pollution and control mountaintop removal coal mining.

"The environmental extremists do not want to listen to our ideas for compromises because their goal is simply to shut down the nation's coal industry, without regard for the people, families and communities affected," Roberts said in a news release issued along with his testimony.

Behind the scenes, UMW officials have worked to try to resolve the mountaintop removal controversy in a way that protects jobs and the environment. Publicly, Roberts has become much more confrontational in his rhetoric against environmental groups.

On Thursday, Roberts focused on the union's arguments against the Kyoto Protocol, an international treaty to reduce air pollutants that contribute to global warming.

"Without the inclusion of developing nations, this treaty will do nothing to remedy the amount of greenhouse gases being pumped into the world's air," Roberts said in the release.

"Yet, some environmentalists do not want to listen to logic," he said. "They have a short-sighted agenda, and they do not care who gets harmed in order to fulfill that agenda, whether it be coal miners, persons living on fixed incomes, small business owners - whoever," he said.

In his testimony on mountaintop removal, Roberts noted that federal regulators and environmentalists had settled part of a federal court lawsuit so that permits could be issued, but with more scrutiny from government agencies.

Roberts added that, "Unfortunately, some environmental groups didn't like the result and filed for an injunction to block the settlement.

"The federal judge blocked the settlement and scheduled a hearing on the injunction for September," Roberts said.

"If the company concludes that it will never be allowed to mine those reserves and withdraws the equipment from the mine, those miners may never go back to work," he said.

Chief U.S. District Judge Charles Haden II has not issued an injunction to block the settlement. Coal companies have gone to court to challenge the settlement agreement.

Environmentalists challenged an expansion permit for Arch Coal Inc.'s Dal-Tex mine after the U.S. Army Corps of Engineers exempted it from the additional scrutiny called for in the settlement.

In response, Haden issued a preliminary injunction that halted the expansion until a full trial in the case, scheduled for September. Less than a week later, Arch Coal announced it would close Dal-Tex and lay off nearly 400 miners who work there.

Doug Gibson, a press spokesman for the mine workers, said the "settlement" that Roberts referred to wasn't the lawsuit settlement, but instead was federal agencies' decision to exempt the Dal-Tex permit from additional scrutiny.