As I blogged earlier, the US Nuclear Regulatory Commission (NRC) and the US Department of Energy have had teams of nuclear and radioactivity experts in Japan since Tuesday, 45 in total.
At 17:49 tonight Eastern Time the BBC has reported that Greg Jaczko, chairman of the NRC, said attempts to cool reactors with sea water and prevent them from melting down appeared to be failing. Emergency workers in the vicinity could be exposed to "potentially lethal" radiation doses, he said.
Mr Jaczko told a congressional energy and commerce subcommittee hearing in Washington that there appeared to be serious problems with attempts to cool three reactors.
"We believe that around the reactor site there are high levels of radiation," he said.
"It would be very difficult for emergency workers to get near the reactors. The doses they could experience would potentially be lethal doses in a very short period of time."
It also reports that US Energy Secretary Steven Chu has said that the situation at the plant appears to be more serious than the partial meltdown at the Three Mile Island nuclear plant in Pennsylvania in 1979.
TEPCO has said it is seeking to restore the power supply to the plant's cooling systems "as soon as possible". I don't understand why this has still not happened. If restoration of off-site power had happened at Daiicihi at the same time off-site power was restored to Daini, I suspect that we might not be in the precarious situation we are in.
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