The operators of the plant, Tokyo Electric Power Co. (TEPCO), deployed over 800 workers inside the No. 2 reactor at the No. 1 plant between December 2016 and February 2017 -- but so far, they have been unable to identify the location of the melted nuclear fuel.
TEPCO also plans to conduct studies inside the No. 1 and No. 3 reactors, but they are surely headed for a rough road as the search for the melted nuclear fuel continues to be extremely difficult.
It is likely that struggles in that search will have a negative effect on the government and TEPCO's target of completing the Fukushima decommissioning work between 2041 and 2051.
Apart from humans, robots have also been involved in the search. In the case of the No. 2 reactor for example, robots have been used in the following way.
The mission to get a good look inside the No. 2 reactor containment vessel had four steps. However, a number of unexpected problems emerged along the way.
Heavy machinery giant IHI Corp.'s Keizo Imahori, 38, who oversaw the mechanical boring of the containment vessel in December 2016, explains that, "A number of unexpected dents were found on the floor of the nuclear reactor building."
This was a surprising discovery for Imahori and his team. The presence of the dents meant that it would be difficult for machines to get sufficiently close to the necessary areas to drill a hole, which in turn has a detrimental effect on the entire search for melted nuclear fuel. ■
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