26 Juillet 2017
July 25, 2017
TEPCO releases video of 'nuclear debris' at Fukushima plant
By KOHEI TOMIDA/ Staff Writer
Footage released by Tokyo Electric Power Co. on July 24 shows what is believed to be nuclear fuel debris. The lumps are scattered at the bottom of the containment vessel of the No. 3 reactor at the Fukushima No. 1 nuclear power plant. (Video provided by the International Research Institute for Nuclear Decommissioning)
What is believed to be nuclear fuel debris scattered inside a reactor of the crippled Fukushima No. 1 nuclear power plant can be clearly seen in video footage released by Tokyo Electric Power Co. on July 24.
The four-minute video shows nuclear fuel debris dispersed in an area measuring about 5 meters in diameter directly beneath the No. 3 reactor’s pressure vessel. The video comes from 16 hours’ footage filmed by a remote-controlled submersible robot during a survey by plant operator TEPCO on July 19, 21 and 22.
The released video also shows craggy-shaped material that appears to be nuclear fuel debris hanging like an icicle from equipment at the bottom of the pressure vessel.
As the camera-equipped submersible robot advanced toward the bottom of the containment vessel, it captured how pipes and structures had collapsed in a heap.
Although the company thinks such lumps are highly likely to be nuclear fuel debris due to their shape, it has yet to determine exactly what they are. It is because TEPCO could neither measure radiation levels nor collect material in the probe for analysis.
The operator plans to analyze the collected footage in the days ahead to ascertain the extent of scattered debris.
If, or when, any further robot probe is conducted has yet to be decided.
“We have yet to plan a new survey so far,” a TEPCO official said.
July 25, 2017 (Mainichi Japan)
This still image from a video provided by the International Research Institute for Nuclear Decommissioning shows what appears to be a bolt covered with deposits believed to be melted nuclear fuel at the No. 3 reactor of the Fukushima No. 1 Nuclear Power Plant.
Tokyo Electric Power Co. on July 24 released a new video of a containment vessel at the No. 3 reactor of the ravaged Fukushima No. 1 Nuclear Power Plant.
The video was filmed by an underwater robot, which was sent into the reactor to study the condition of melted fuel debris. The four-minute long footage showed a large amount of lava-like lumps believed to be debris of melted fuel stuck to machines and building frameworks.
Deposits in reactor likely to be fuel debris
The operator of the damaged Fukushima Daiichi nuclear power plant released video footage on Monday of what is likely to be melted fuel debris.
Tokyo Electric Power Company, or TEPCO, found the solidified lumps during a robot inspection of the containment vessel of Fukushima's wrecked No. 3 reactor. The 3-day survey ended on Saturday.
TEPCO had earlier only made public still images from the probe. The 4-minute video shows black or grey lumps hanging down close to a structure just below the reactor.
The lava-like lumps are piled in layers, a phenomenon unknown before the accident.
TEPCO officials say the debris is probably melted nuclear fuel mixed with broken reactor parts.
In addition to metal scaffolding and other structural components, rocks and sand-like sediment can be seen getting stirred up by the movement of the robot.
The government and TEPCO plan further analysis of the footage in order to determine methods for removing the debris.