More problems for decommissioning?

July 13, 2012

Robot probe detects high radiation at No.3 reactor

http://www3.nhk.or.jp/daily/english/20120713_10.html

The operator of the Fukushima Daiichi nuclear plant has detected high levels of radiation in the basement of the No. 3 reactor, with a maximum dose of 360 millisieverts per hour.

Tokyo Electric Power Company sent in a robot on Wednesday to the room where the suppression chamber is located. It was the first robot to probe this area of the plant.

TEPCO released video taken inside. They show that a door on the southwestern side is broken. There is no other apparent damage or sign of water leakage.

But high levels of radiation were detected. Readings exceeded 100 millisieverts per hour in a number of locations. Average levels were higher than those in the No.2 reactor.

Engineers lost control of the remote-controlled robot after around 3 hours of operation. They say there are problems with the connecting cable and they've been unable to regain control.

TEPCO officials say they have no option but to leave the robot where it is for the time being.

This may pose a problem to the utility's efforts to decommission the reactor. The operators are in a hurry to identify and repair damage to the reactor's suppression chamber and containment