Rusnack, a Peabody board member since 2002, is the chair of the audit committee, and a member of the compensation and executive committees of Peabody's board.
Peabody chairman and CEO Gregory Boyce said: “Bill has long been one of St Louis' most preeminent business leaders and is an invaluable member of Peabody's board.
“His vision and leadership have been a major contributor to Peabody's values, strategy and success.”
Rusnack served as president and CEO and a board member for Premcor Inc from 1998 until 2002.
Before joining Premcor, Rusnack was president of ARCO. During his 31-year career at ARCO, Rusnack was also president of ARCO Transportation Company, and vice president of corporate planning.
He served as the chairman of the Trans-Alaska Pipeline Company Owners Committee from 1992 to 1994. He served on the board of Solutia from 2010 to 2012 and Lyondell Petrochemical Company from 1988 to 1993. He also is on the board of Flowserve Corporation in Irving, Texas, and Sempra Energy in San Diego, California.
He is also an investor and a board member of Sequoia Sciences, an early-stage pharmaceutical drug discovery company in St Louis. Rusnack is a founding member and treasurer of the Saint Louis Arch Angels.