Unit-3 and Unit-4 are 2-loop Combustion Engineering (C-E) System 80 plants with major components and construction handled domestically under a technology transfer agreement.

Unit-5 and Unit-6 are based on the Ulchin (now Hanul) Unit-3 OPR-1000 Korean Standard Nuclear Power Plant design.

[2][3] In November 2012, security checkups prompted by the Fukushima Daiichi nuclear disaster revealed that from 2003, eight suppliers had forged quality certificates for a delivered 7,682 items to the plant.

Knowledge Economy Minister Hong Suk-woo responded that the "government plans to further increase its efforts to export nuclear reactors.

In this regard, the government will quickly provide all necessary and accurate facts to prospective foreign buyers to make sure there is not a single shred of doubt left over the safety of the country's nuclear reactors".