4 Die, 2,500 Flee as Explosion Reduces Fertilizer Plant to Crater

An explosion demolished a farm chemical plant Tuesday, killing at least four workers and leaving only a crater where the seven-story building had stood. Eighteen people were injured.

The early morning blast at the Terra Industries plant, Iowa’s biggest producer of nitrogen-based fertilizers, released a cloud of ammonia gas, forcing the evacuation of 2,500 people from towns up to 20 miles away.

The ammonia leak was brought under control by late afternoon, and all but 100 residents were allowed to return home.

The cause of the explosion was not immediately known.

“There was a building there. It’s gone,” said Dick Braun, a firefighter in nearby Salix.

The blast at the plant along the Missouri River, on the Nebraska-Iowa line, was felt 30 miles away. It twisted steel beams and tossed one 500 yards into a cornfield, Braun said.

Fire officials said most of the buildings in the refinery-like complex 10 miles south of Sioux City were damaged, and the main, seven-story building was reduced to a crater. The scene was closed off to all but emergency workers.

“This is worse than any tornado I’ve seen, as far as destruction,” said Salix Fire Chief Garold Smith.

Shrapnel thrown out by the explosion punctured one or both of the plant’s two 15,000-ton refrigerated ammonia storage tanks, said Burton Joyce, Terra’s president and chief executive officer.

The company estimated that one of the tanks held 5,700 tons of ammonia but said it did not know how much had escaped.

Flying debris also punctured a nearby nitric acid tank, spilling up to 100 tons of the corrosive liquid.