A new investigative robot, equipped with a censoring unit hanging through metal grating, is scheduled to be send into the No. 1 reactor at the Fukushima No. 1 nuclear power plant in the coming months. (Kohei Tomida)
HITACHI, Ibaraki Prefecture–Another robot has been developed for the elusive goal of locating melted fuel and surveying the interior of the No. 1 reactor at the Fukushima No. 1 nuclear plant.
A team of engineers and researchers from Hitachi-GE Nuclear Energy Ltd. and the International Research Institute for Nuclear Decommissioning revealed the robot on Feb. 3.
Tokyo Electric Power Co., operator of the plant, plans to deploy the robot into the No. 1 reactor before the end of March.
The robot will be fitted with a censoring unit mounted with a camera, dosimeter and lighting. Its purpose is to give TEPCO an idea of the location and condition of the melted nuclear fuel in the reactor.
Most of the melted fuel is believed to have fallen through the reactor’s pressure vessel, landed on the bottom of the surrounding containment vessel, and is soaking in cooling water about 2 meters deep.
The new robot will maneuver around metal grating originally set up for maintenance work about 3.5 meters above the bottom of the containment vessel.
At each of five survey points, the robot will lower the censoring unit through the grating. The unit can operate in water.
In April 2015, TEPCO sent two robots into the No. 1 reactor, but they could not locate the melted fuel.
One of them became stuck, and high radiation levels disabled the camera on the other. TEPCO abandoned the machines in the reactor.
On Jan. 30, a remote controlled video camera sent into the No. 2 reactor took what are believed to be the first images of melted fuel at the plant.