The 1998-1999 simulation revealed that destruction of the Yongbyon nuclear plant could cause enormous destruction, with nuclear fallout as far away as China and Japan. U.S. research institutes have conducted similar simulations, but this is the first time it has been confirmed that South Korean military authorities commissioned them.
If the 8 megawatt research reactor and 5 megawatt test reactor at Yongbyon were destroyed by bombs while they were in operation, the simulation showed that radiation would affect people as far as 1,400 km away. Eighty to 100 percent of those living within a 10-15 km radius of the reactors would die within two months, and only 20 percent within a 30-80km radius were expected to survive. As Seoul is about 200 km away from Yongbyon, the capital would suffer direct radiation damage.
Areas 400-1,400 km away from Yongbyon would still experience 5 rem of radiation, about 10 times the recommended maximum annual exposure. Even five years after air strikes, the area within a 700 km radius of Yongbyon could be radioactive.
If all of Yongbyon's nuclear facilities besides the reactors such as the reprocessing facilities and nuclear waste storage facilities were destroyed, the devastation would be even greater. About a quarter of people living within 50 km of the facilities would die within hours, while the soil of the entire Korean Peninsula would be contaminated for five to 10 years.