Coal king Peabody cleans up

WRIGHT, Wyo. — A mammoth shovel scrapes about 70 tons of coal shards off a 60-foot-high black wall like ice cream from a long, deep vat.

The power shovel's boom pirouettes and dumps its load into a truck bed with a resounding thud, kicking up a haze of black dust. Four scoops later, the outsized truck — think 12-foot-tall tires — brimming with a fresh dark mound, rolls off. Without missing a beat, the shovel dives back into the bounty, releasing its next load just as another truck backs in.

The scene — repeated around the clock here at the world's largest coal mine, Peabody Energy's North Antelope Rochelle Mine in the Powder River Basin — underscores both the abundance and the grimy nature of the USA's most plentiful energy resource.

As oil and natural-gas prices remain high and lawmakers agonize over ...