Tokyo Electric Power Co. said fuel rods are fully exposed in the No. 1 reactor at its stricken Fukushima Dai-Ichi nuclear plant, setting back the utility’s plan to resolve the crisis.
The water level is 1 meter (3.3 feet) below the base of the fuel assembly, Junichi Matsumoto, a general manager at the utility known as Tepco, told reporters at a briefing in Tokyo. Melted fuel has dropped to the bottom of the pressure vessel and is still being cooled, Matsumoto said. The company doesn’t know how long the rods have been exposed, he said.
Tepco is trying to contain the worst nuclear disaster since Chernobyl after a quake and tsunami two months ago knocked out power and cooling systems at the Fukushima station. The utility planned to flood the No. 1 containment chamber, which surrounds the reactor vessel, in a procedure known as water entombment to prevent fuel from overheating.
“I’ve been saying from the beginning the water tomb plan won’t work,” said Tadashi Narabayashi, a professor of nuclear engineering at Hokkaido University. “Tepco must work on a water circulation cooling system as soon as possible. They’ve been going round and round in circles and now realize this is what they need to do.”