On the 24th June 2021, Tepco revealed their updated decommissioning plan for Fukushima nuclear plant.
They delayed the schedule by one year due to the ongoing pandemic.
The nuclear fuel is assumed to be in the molten state from reactor 1 to 3. As reactor 2 has been relatively the most investigated, Tepco will start focusing on reactor 2.
The robot arm, which is expected to reach the molten fuel, has been developed by International Research Institute for Nuclear Decommissioning (IRID), Mitsubishi heavy industries and Veolia Nuclear Solutions. As the development process was completed in The UK, the robot arm was transported to Japan on 10th July and transferred the domestic factory in Kobe. After the inspection, mockup testing is planned to be implemented. The detailed dates are not announced.
By the 24th May 2021, still high level of radiation was detected outside the primary containment vessel (PCV) of reactor 2 up to 0.53 Sv/h. The picture attached is the bulkhead part of the PCV in reactor 2.
https://www.tepco.co.jp/decommission/information/newsrelease/reference/pdf/2021/2h/rf_20210712_2.pdf
https://www.tepco.co.jp/decommission/information/committee/roadmap_progress/2021-j.html