High levels of radiation were detected near an area where steam was spotted July 23 at the No. 3 reactor building of the stricken Fukushima No. 1 nuclear plant, Tokyo Electric Power Co., the plant operator, said.
High levels of radiation were detected near an area where steam was spotted July 23 at the No. 3 reactor building of the stricken Fukushima No. 1 nuclear plant, Tokyo Electric Power Co., the plant operator, said.
TEPCO gave a measurement of 562 millisieverts per hour.
The Nuclear Regulation Authority, the government's nuclear industry watchdog, instructed TEPCO to investigate further because the dose level is high.
What appeared to be steam was spotted near an equipment storage pool on the fifth floor of the No. 3 reactor building around 9:05 a.m. There was a similar occurrence on the morning of July 18.
In the latest incident, TEPCO measured radiation levels in 24 other locations around the fifth floor of the reactor building. The maximum dose was 2,170 millisieverts per hour, while the minimum was 137 millisieverts per hour.
TEPCO officials said rain that fell on the night of July 22 likely made its way to around the No. 3 reactor’s containment vessel and evaporated due to heat from nuclear fuel that remained trapped.
Workers have not been able to approach the fifth floor of the No. 3 reactor building due to high levels of radiation following an explosion after the March 11, 2011, Great East Japan Earthquake and tsunami.
TEPCO has been removing rubble with remote-controlled cranes at the building.