Newly found Fukushima plant contamination may delay cleaning


TOKYO (AP) – A draft investigative report of the Fukushima nuclear meltdown adopted by Japanese nuclear regulators in 2011 states that it has detected dangerously high levels of radioactive contamination in two out of three reactors, including about MorningShip challenges. Concerns have been added.

The interim report stated that data collected by investigators showed that the sealing plugs sitting in the reactors of Nos. 2 and 3 were atomically contaminated as fuel debris that melted and as of March 2011 After the tsunami and earthquake the reactors had fallen down. .

Experts said the bottom of the seal plug, a triple-layered concrete disc-shaped lid 12 meters (39 ft) in diameter sitting above the primary control vessel, is coated with high levels of radioactive cesium 137.

The report stated that the lid of the No. 1 reactor was less contaminated, as the plug was knocked slightly out of place and disintegrated due to the effects of the hydrogen explosion.

Experts measured radiation levels at several locations inside the three reactor buildings, and investigated how radioactive material moved and safety equipment worked during the crash. He also said that the venting effort at Unit 2 to prevent reactor damage never worked, and that safety measures and equipment design still needed to be investigated.

Lid contamination does not affect the environment because reactor vessels are enclosed inside reactor buildings. The report did not provide much information about whether lid contamination would affect decommissioning progress.

Nuclear Regulation Commission chairman Toyoshi Phuketa called the findings “extremely serious” and said they would make the molten fuel “more difficult”. He said that finding out how to remove eyelids would be a big challenge.

Removing an estimated 900 tons of melted fuel debris from three reactors is a difficult task that has taken decades, and officials have not been described when or how it could be finished.

The Fukushima plant was to begin removing molten fuel debris from the first two reactors, Unit 2, later this year before the 10th anniversary of the crash. But in December, the plant operator Tokyo Electric Power Company and the government announced a delay until 2022. He said the development of a robotic branch to remove debris – a joint project with Britain – has been delayed due to the epidemic.

Under the current plan, a remote-controlled robotic arm would be inserted to access the melted fuel from the side of the reactor and the mixed fuel along the concrete floor of the reactor. Eventually the eyelids also have to be removed, but their contamination is a major setback.

The team of experts entered areas inside the three reactors that were highly contaminated and inaccessible after the first radiation levels. They are asking for data and evidence before they get lost in the cleanup.

Large-scale radiation from the reactors has evacuated around 160,000 people from around the plant. Thousands are still unable to return home.

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