TOKYO (AP) – Images captured by a robotic probe inside one of three reactors melted down at the Fukushima nuclear power plant in Japan. They showed exposed steel bars in the main structure of the structure and parts of the external density of the concrete wall missing, raising concerns about earthquake resistance in the event of another major disaster.
Plant operator, Tokyo Power Electric Company Holdings, has been sending robotic probes inside the first container of Unit 1 since last year. The new findings released Tuesday were based on the latest exploration conducted at the end of March.
A remotely operated underwater vehicle named ROV-A2 was sent inside the base of Unit 1, a support structure under the core to the right. It returns with images first seen when the earthquake and tsunami closed the plant 12 years ago. About the space inside the base there traces of melted meat can most likely be found.
The roughly five-minute video – part of 39 hours-long footage taken by the robot – shows the 120-centimeter (3.9-foot) thick concrete exterior base significantly damaged near its bottom, exposing steel reinforcement inside. .
TEPCO spokesman Keisuke Matsuo told reporters Tuesday that the steel supply is largely intact, but the company plans to conduct further data and image analysis over the next two months to explore how the reactor’s resistance to motion can be improved.
Images of the exposed steel support have raised concerns about the safety of the reactor.
About 880 tons of highly radioactive molten nuclear fuel remain inside the three reactors. Robotic tests have provided some information, but the state of the wreckage is still largely unknown. About 10 times the amount of contaminated fuel that was removed in the cleanup of the Three Mile Island nuclear plant in the United States after the 1979 partial core meltdown.
Fukushima Gov. Masao Uchibori urged TEPCO to “quickly assess the level of movement resistance and provide information in a way that the population can easily understand and care about the residents and people around the country.”
Video captured by the robot also shows the collapsed equipment along with other types of debris, possibly nuclear fuel that fell from the core and hardened, piled up to a height of 40-50 centimeters (1.3-1.6 feet) from the bottom. the main containment room, Matsuo said. The request is lower than images taken at two other reactors during earlier internal inspections, suggesting that the meltdowns in each reactor may have progressed differently, company officials said.
Matsuo said the data collected from the latest tracking will help experts come up with methods for removing debris and solving the 2011 meltdowns. TEPCO also plans to use the data to create three-dimensional maps of the melted fuel and the individual debris, which would take about a year.
Based on data collected from earlier tests and simulations, experts said most of the molten material inside Unit 1 fell to the bottom of the primary containment chamber, but some could also have fallen onto the concrete foundation — a situation that is already alarming. a very difficult task to undertake.
The trial for removing the broken debris is expected to begin in Unit 2 later this year after a nearly two-year delay. The spent fuel from the removal of the reactor tank Unit 1 has started in 2027 after a 10-year delay. After all the fuel was removed from the tanks, the focus turned in 2031 to removing the molten debris from the reactors.