UPDATE 1-South Carolina utility CEO steps down after nuclear project nixed

(Adds background on nuclear project)

Aug 25 (Reuters) - The chief executive officer of South Carolina's state-owned electric utility announced his resignation on Friday, less than a month after the utility abandoned a nuclear project that was stymied by delays and billions of dollars in cost overruns.

Lonnie Carter will step down from his post as CEO and president of utility Santee Cooper, ending more than 13 years in the position and more than three decades with the utility, Carter and Santee Cooper's board of directors said at a specially convened meeting.

Carter's resignation comes amid calls by state politicians for further management shake-up and legislative investigations on what caused the nuclear expansion project known as V.C. Summer to fail after roughly a decade in the making.

The Santee Cooper board of directors voted on July 31 to halt construction on the project, once considered the start of a U.S. nuclear power renaissance. Soon after the decision, 5,000 workers on the site were laid off, leaving behind two unfinished nuclear reactors.

About $9 billion had been spent on construction when V.C. Summer was canceled. Costs were estimated to balloon 75 percent over the initial budget, to as much as $24 billion, before completion.

Santee Cooper owns 45 percent of the project, with 55 percent owned by a unit of SCANA Corp. (Reporting by Laila Kearney; Editing by Bernadette Baum and Dan Grebler)