(Photo: Reactor1, December 2019. [URL])
The investigation inside reactor1 was planned to start on the 12th of January, 2022 until August, however, it encountered multiple troubles in the process of preparation and the restarting schedule is unforeseeable.
Tepco was attempting to install four rings inside the primary containment vessel (PCV) of reactor1 by utilizing a drone. The rings are 30 cm in diameter. They were expected to ensure the route for the next drone to pass, which is specialized to analyze the nuclear debris assumed to remain in PCV.
However, at the moment when engineers turned on all the devices, technical errors occurred in radiation level inspector and the clock of the drone’s camera.
The causes have not been identified. The radiation level near the drone’s entry point is still lethally high. Each worker cannot remain on the site for over 30 minutes, so eight engineers take turns to work.