Yongbyon may be having trouble

North Korea may have encountered safety problems in the cooling systems at its nuclear facilities in Yongbyon, risking a leak of radioactive water or a fire, a U.S. report said.

A report posted on 38 North, the website for the U.S.-Korea Institute at the Paul H. Nitze School of Advanced International Studies at Johns Hopkins University, said Monday that Pyongyang appeared to have experienced some malfunctions in the cooling systems due to recent heavy rainfall that destroyed infrastructure near a riverside, according to some satellite images.

“Recent commercial satellite imagery indicates that North Korea may have experienced problems ensuring an adequate water supply essential for the operation of reactor cooling systems,” said Nick Hansen, a U.S. specialist on defense, in the report.

“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.”

Due to the alleged problems, the five-megawatt nuclear reactor that allegedly restarted recently appeared to have been shut down or is working at a low-power level, he said.

According to a satellite image by DigitalGlobe on Feb. 9, snow still covered several buildings and the reactor.

Hansen said the reactor was possibly shut down and the buildings did not generate enough heat to melt the snow on their roofs.

North Korea’s quick construction of water channel excavations and dam construction from December 2013 until February could have been due to the shuttered reactor, he said, and to ensure sufficient water for the cooling system of the experimental light water reactor that is now allegedly near completion.

Despite the measures, Hansen noted, the Yongbyon reactors might have unreliable supplies of water as the infrastructure near the river is easily washed away by floods.

“If the five-megawatt reactor’s secondary cooling system were to fail, so would the entire cooling system,” he said. “The result would be a fire in the graphite core and the release of radioactivity.”

South Korean President Park Geun-hye noted the danger of a radioactive leak from the Yongbyon facilities during her visit to The Hague in an interview with a Dutch television network last month, which she said “could lead to a disaster potentially worse than Chernobyl.”

But Hansen contradicted Park, saying it would not be worse than the Chernobyl case as the Yongbyon facility is small.

“However, a radioactive release in the atmosphere or river would cause an expanded local area of contamination,” he added. “Also, Pyongyang’s likely lack of transparency could create a regional crisis, panicking the public in surrounding countries and raising tensions with governments anxious for further information.”

BY KIM HEE-JIN [heejin@joongang.co.kr]