TOKYO: A rise in radiation halted the clean-up of radioactive water at Japan's Fukushimi nuclear power station Saturday hours after it got under way, a fresh setback to efforts to restore control over the quake-stricken plant. The power plant has been leaking radiation into the atmosphere ever since the March 11 quake and tsunami and both China and South Korea have expressed concern over the possibility of further leaks into the sea. Tokyo Electric Power Co., which operates the tsunami-hit Fukushima Dai-ichi nuclear plant, is investigating the cause of the increase in radiation and is not sure when it will resume the clean-up operation, company spokesman Junichi Matsumoto said. Fresh water is being pumped in to cool damaged reactor cores, and is getting contaminated in the process. Some 105,000 tons of highly radioactive water have pooled across the plant, and could overflow within a couple of weeks if action is not taken. In earlier tests, the water treatment system reduced cesium levels in the water to about one-10,000th of their original levels. The system began full operations Friday night after a series of problems involving leaks and valve flaws. The system was suspended early Saturday when workers detected a sharp radiation increase in the system's cesium-absorbing component, Matsumoto said. Radioactivity in one of 24 cartridges, which was expected to last for a few weeks, had already reached its limit within five hours, he said.
