BISMARCK, N.D., Aug. 13, 2025 /PRNewswire/ -- MDU Resources Group, Inc. (NYSE: MDU) today announced the election of Charles M. Kelley and Tammy J. Miller to its board of directors, effective Aug. 12, 2025.Kelley brings more than four decades of experience in the natural gas industry, including a distinguished 25-year career at ONEOK, Inc., where he most recently served as senior vice president of Natural Gas Pipelines. He led strategic growth initiatives and commercial activities for ONEOK's natural gas pip ...