“All of us at Big River appreciate Mark’s contributions to the launch and early operations of our company and our mill,” said chief executive officer Dave Stickler. “Knowing that startups are Mark’s true passion, the Big River Steel family wishes Mark every success in his future ventures.”

Bula was a member of Big River’s original development team, and the company said he was instrumental in developing the marketing and sales plans that led to its strong performance in its first 15 months of operation.

Bula is to be succeeded by Keith Shuttlesworth, who currently serves as the general manager of Big River’s carbon sales group.

Shuttlesworth came to Big River from United States Steel Corporation, where he had worked for 18 years and had managed some of U.S. Steel’s most important customer relationships.