Construction of the plant is scheduled to be completed in 2015.
Last week, documents including layouts of nuclear facilities and personal information of nuclear workers were published online.
Local media said the unidentified people who posted images of the stolen nuclear documents imprinted with “WHO AM I?” on a South Korean blog were hackers. The company said that the safety of the country’s nuclear power plants was not affected.
Korea Hydro ran drills on Monday and Tuesday to prepare workers in the event of hacking attacks.