Dave Raisbeck stepped down at the beginning of June followed by Rick George and now Ingram. The board does not intend to fill the vacancies left by Raisbeck, George or Ingram.

During his tenure, Ingram served on two board committees, namely the Safety, Operations and Environment Committee (SOE) and the Management Resources and Compensation Committee.

"Mr. Ingram's insight and guidance was particularly appreciated by the SOE Committee," said Paul Haggis, chairman of the board. "The board wishes to thank Tony for his contributions to the company."