Thirteen years after the catastrophic tsunami that led to one of the worst nuclear disasters in history, Japan has commenced a critical operation to remove a small amount of radioactive debris from the Fukushima Daiichi nuclear plant. This operation signifies a pivotal stage in the long and challenging process of decommissioning the damaged plant.
The Tokyo Electric Power Company (TEPCO) has begun what is known as the ‘pilot extraction operation.’ This initial mission, which began after overcoming significant technical hurdles, is expected to last about two weeks. TEPCO had to halt a previously scheduled attempt due to equipment installation errors but has now resolved these issues.
The Fukushima Daiichi nuclear plant was severely affected by a 9.0-magnitude earthquake in March 2011, triggering a tsunami that compromised the plant’s cooling systems. This led to the meltdown of three reactors, releasing approximately 880 tons of highly radioactive material. The removal of this hazardous debris is one of the most challenging aspects of the decades-long decommissioning project.
Given the extremely high radiation levels, advanced robotic technology has been employed to carry out the extraction. Among the tools being used is a robotic arm that functions like a fishing rod, remotely operated to lower a claw-like grip into the reactor to retrieve debris. This robotic device can extend up to 72 feet (22 meters) into the containment vessel to collect less than 0.1 ounces (3 grams) of the material.
The high-stakes mission involves maneuvering the robotic arm via five 1.5-meter-long pipes connected in sequence. The robot itself extends about 6 meters (20 feet) inside the reactor and is operated remotely due to the fatal radiation levels. The front of the robot is equipped with tongs, a light, and a camera to safely snip off and collect the debris, all while operators work from a separate building.
The collected debris sample will be placed in secure canisters and sent to multiple laboratories for detailed analysis. TEPCO limits daily operations to two hours to minimize radiation exposure risks for workers. Eight six-member teams take turns, with each group allowed to operate for a maximum of 15 minutes.
This pilot extraction operation is just the beginning of a much longer process aimed at safely removing and relocating the radioactive material. Experts, including Lake Barrett who oversaw the cleanup after the Three Mile Island disaster, emphasize the importance of this initial step to understand the state of the melted fuel debris, which is crucial for future removal and storage plans.
However, the road ahead is fraught with challenges. TEPCO must develop stronger robots and additional capabilities for larger-scale debris removal. The remaining reactors, Units 1 and 3, are in worse condition and will require even more time and effort to address. TEPCO is planning additional missions involving small drones for further inspections and is working on developing micro drones for areas with higher water levels.
The decommissioning of the Fukushima Daiichi plant is expected to take 30-40 years, although some experts suggest it could take up to a century. The complexity and risks involved make it a daunting task, necessitating advanced technology and meticulous planning.
The broader strategy to manage the disaster’s long-term consequences also includes initiatives like releasing treated wastewater into the Pacific Ocean, a move that has stirred diplomatic tensions with neighboring countries. Additionally, efforts to rebuild trust in Fukushima’s agricultural products are ongoing, with some successes like the sale of Fukushima-grown peaches at London’s Harrods store.
Japan’s journey to mitigate the impact of the Fukushima disaster continues with this critical step, showcasing the blend of resilience and technological innovation required to tackle one of the most formidable nuclear decommissioning projects in history.