David A. Heacock, president of Dominion Nuclear and the Dominion Resources’ chief nuclear officer, will retire on March 1.

Beginning Oct. 1, Daniel G. Stoddard, senior vice president of nuclear operations, will become senior vice president and chief nuclear officer. Heacock will remain president of Dominion Nuclear until his retirement.

Stoddard, a graduate of the U.S. Naval Academy with a bachelor’s degree in marine engineering, earned his master’s degree in nuclear engineering from the University of Virginia. He joined Dominion in July 2006.

Dominion is one of the nation’s largest producers and transporters of energy, with a portfolio of approximately 25,700 megawatts of generation, 14,400 miles of natural gas transmission, gathering and storage pipeline, and 6,500 miles of electric transmission lines.