The Powder River Basin in the Western United States provides cheap, abundant coal. But even there, two major coal mines have shuttered due to economic challenges facing America’s coal sector.

Blackjewel, the owner of the two mines in the basin, declared bankruptcy Monday, planning to reorganize and stay afloat. Then bank financing fell through and the mines abruptly shuttered.

“Yesterday was kind of like a heart attack in the Powder River Basin,” said Robert Godby, energy economist at the University of Wyoming. “It was a kind of out-of-the-blue outcome. People woke up that morning thinking they had a job. And by the end of the day they didn’t.”

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