Rapid meltdown in No.1 reactor
Sunday, May 15, 2011
Tokyo Electric Power Company, the operator of the Fukushima Daiichi nuclear power plant, says most of the fuel rods in the No.1 reactor had dropped to the bottom of the pressure vessel within 16 hours of the earthquake on March 11th.
The utility revealed its study on the subject on Sunday.
TEPCO said it analyzed the data and calculated a timeline for the developments in the No. 1 reactor on the assumption that the reactor lost its cooling system as soon as it was hit by the tsunami.
The firm said that within about 3 hours after the reactor automatically shut down, the cooling water had evaporated to a level at the top of the rods.
In the next hour and a half, parts of the fuel rods are believed to have begun melting.
The temperature of the fuel rods is believed to have reached 2,800 degrees Celsius at this stage, and the meltdown advanced rapidly.
Almost of all the fuel rods melted and dropped to the bottom of the pressure vessel by 6:50 am on March 12th.