A grain storage bin that ruptured last weekend in north-central South Dakota halted rail loadings at the elevator after 1.5 million bushels of corn spilled over the train tracks, an executive of the South Dakota Wheat Growers said.

Corn remained on the ground at the facility in Mellette, South Dakota, following a structural failure of the steel bin built in 2000, said Stephen Briggs, senior vice president of agronomy and corporate marketing for the cooperative.

"We're not able to load trains at that facility yet," Briggs said. "As soon as the insurance company will allow us to go at it, we'll load it in a train or whatever the market is telling us what to do."

The cause of the rupture was not yet known, he said.

The grain elevator has a local track that feeds into a line owned by the BNSF Railway Company, which has tracks running to ports at the U.S. Pacific Northwest and the U.S. Gulf Coast.

Briggs said the bin could store as much as 1.75 million bushels and was filled with roughly 1.5 million bushels of corn. That is enough grain to fill more than four 100-car unit trains or more than 1,600 semitrucks.

The grain will shipped and then stored at other facilities owned by the Wheat Growers, which also handles soybeans as well as winter and spring wheat varieties, Briggs said.

South Dakota grew the sixth most corn in the United States last year, according to the U.S. Agriculture Department. (Reuters)