An extendable robot has resumed its entry into one of the damaged reactors at the Fukushima Daiichi nuclear power plant in order to retrieve a fragment of melted fuel debris. This comes nearly three weeks after its previous attempt was suspended due to a technical issue. The collection of this tiny sample marks the beginning of the most challenging phase in the decades-long decommissioning process for the plant, which suffered severe damage during the 2011 earthquake and tsunami disaster.
The mission to retrieve a sample of spent fuel debris from inside Unit 2 reactor was initially scheduled to begin on August 22nd but had to be postponed when workers discovered that a set of five add-on pipes, each measuring 1.5 meters (5 feet), were arranged incorrectly and could not be corrected within their radiation exposure time limit. These pipes were intended to push and maneuver the robot inside and then pull it back out once it had completed its task. The robot is operated remotely from a safer location once inside.
The extendable robot, nicknamed “telesco,” can reach up to approximately 22 meters (72 feet) with the help of these pipes, allowing it to collect a fragment from the surface of the melted fuel mound using tongs attached to its device. The entire mission is expected to last around two weeks.
The mix-up with the pipes was considered by Tokyo Electric Power Company Holdings (TEPCO), which operates Fukushima Daiichi, as a “basic mistake.” This error caused disappointment among officials and local residents alike, prompting Industry Minister Ken Saito to order TEPCO President Tomoaki Kobayakawa an investigation into its cause and preventive measures before resuming operations.
TEPCO determined that lack of attention, checking, and communication between operators and ground workers led to this mishap. By Monday, all equipment had been reassembled correctly in preparation for another attempt.
The ultimate goal is for this operation is bring back less than 3 grams (0.1 ounce) out of an estimated total mass of 880 tons worth fatally radioactive molten fuel that remains across three reactors at Fukushima Daiichi. Experts believe that this small sample will provide crucial data for developing future decommissioning methods as well as necessary technology and robots.
Despite criticism regarding its feasibility, both TEPCO and government authorities are committed to completing cleanup efforts within a timeframe ranging from 30-40 years following meltdown events at Fukushima Daiichi in accordance with their established target date soon after those incidents occurred.
