Experts worry about a possible radiation leak at the old 5 MW nuclear reactor in North Korea's Yongbyon as its cooling system has reportedly been under repair.
"The recently restarted 5 MW plutonium production reactor may have been temporarily shut down or operated at a lower power level in early 2014 in order to repair problems with the secondary cooling system’s water supply," North Korea expert Nick Hansen said in a report for the specialist website 38 North at Johns Hopkins University on Monday.
"These difficulties resulted from the extensive rainfall and subsequent flooding in July 2013, which moved the main channel in the Kuryong River away from the water supply, filled the collection cisterns and ponds with sand and possibly destroyed pipes leading to them that had been laid along the river bottom."
The North quickly completed major water channel excavations and dam construction from December 2013 by February of this year to ensure adequate water would be available for the cooling system of the experimental light water reactor, Hansen adds. "Despite these short-term fixes, the danger posed by an unreliable supply of water for the Yongbyon reactors remains, particularly since the channels and dam constructed are made from sand and could be washed away by future floods."
"If the 5 MW reactor's secondary cooling system were to fail, so would the entire cooling system. The result would be a fire in the graphite core and the release of radioactivity," he warns.