📎 AI Summary:
The thread centers on a Bloomberg report about a setback at the Fukushima Dai-ichi No. 1 reactor, where repaired gauges showed the water level is about a meter below the fuel assembly, with fuel rods fully exposed and the water-entombment plan needing revision due to possible pressure-vessel damage and leakage. The key question raised is whether a hole in the pressure vessel is contributing to the lower-than-expected water level, with contributors focusing on how melted fuel is still being cooled and what the revised strategy should be. Overall sentiment is serious and concerned, emphasizing worsening conditions and uncertainty after the quake and tsunami disrupted cooling systems.

whoosh

Cooler King
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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.

Tepco is trying to contain the worst nuclear disaster since Chernobyl after a quake and tsunami knocked out power equipment 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.

“The plan needs to be revised,” Matsumoto said. “We can’t deny the possibility that a hole in the pressure vessel caused water to leak.”

The surface temperature of the pressure vessel is between 100 and 120 degrees Celsius (248 Fahrenheit), meaning melted fuel are still getting cooled by steam and water, Matsumoto said.

Fixing Gauges

The utility discovered the water levels in the reactor vessel were lower than thought after repairing a gauge on May 10, Takeo Iwamoto, spokesman at Tepco, said by telephone today. Workers last week started entering the No. 1 reactor building for the first time since a blast destroyed its roof.
Tepco: Fukushima Fuel Rods Are Fully Exposed - Bloomberg