17 Avril 2015
April 17, 2015
Tokyo Electric Power Co. (TEPCO), the operator of the stricken Fukushima No. 1 nuclear power plant, on April 16 released additional footage taken inside a highly radioactive nuclear reactor containment vessel.
The images recorded on April 15 were sent from a robotic probe the utility had sent inside the containment vessel of the No. 1 reactor at the Fukushima No. 1 Nuclear Power Plant. It was the second robot to enter the highly radioactive unit as the first one sent in on April 10 had stopped moving a few hours after the probe operation began.
The footage captured by the second robot showed no major damage in an air-conditioning unit on the first floor of the reactor vessel. Meanwhile, parts of lead curtains used to reduce the radiation impact on pipes and other equipment were seen fallen on the steel mesh floor.
The second robot traveled in different areas on the ground level from the first probe. The latest probe found fewer objects scattered on the floor than the first robot.
The air radiation dosage inside the vessel was up to 8.3 sieverts per hour, excluding the time when the figure instantaneously skyrocketed due to the noise from the dosimeter, while temperatures measured at around 20 degrees Celsius.
TEPCO continued the probe with the robot on April 16 and the results of the investigation will be released on April 17 or later.
While the first robot cannot be retrieved from the vessel, the utility is set to recover the second robot sometime after April 17.
THE ASAHI SHIMBUN
The second shape-shifting robotic probe sent into the Fukushima No. 1 nuclear power plant has successfully surveyed the inside of a reactor after the failure of the first unit, the plant operator announced on April 16.
The robot was sent into the containment vessel inside the No. 1 reactor building on April 15 and scanned along an approximately 15-meter-long path, Tokyo Electric Power Co. said.
The machine was sent in to complete the mission of the first unit, which stalled April 10 just hours after it was sent inside the reactor.
The second robot measured radiation levels in three locations inside the containment vessel, which varied from a deadly 6.7 to 8.3 sieverts per hour.
The figures were similar to the measurements taken by the first robot, which read between 7.0 and 9.7 sieverts per hour in six locations.
All of those measurements indicate sufficient levels of radiation to kill a human in about one hour.
The identical robot units were developed by the International Research Institute for Nuclear Decommissioning to chart areas inside reactor containment vessels where humans cannot enter because of high radiation levels. Three reactors at the plant experienced meltdowns following the March 2011 Great East Japan Earthquake and tsunami.
Each robot is 60 centimeters long in its normal state, but can change shape depending on the space it is trying to enter. The probes are operated via connecting cables.
The utility plans to analyze the footage and radioactivity readings taken by the robots in hopes of utilizing the data when eventually removing the melted nuclear fuel from inside the building.
The second robot is scheduled to be retrieved on April 17.