A relatively high level of radioactivity was detected in ditch water around tanks at the Fukushima No. 1 nuclear plant, but Tokyo Electric Power Co. has not pinpointed the cause of the latest contamination.
A relatively high level of radioactivity was detected in ditch water around tanks at the Fukushima No. 1 nuclear plant, but Tokyo Electric Power Co. has not pinpointed the cause of the latest contamination.
TEPCO said on March 5 that the tanks store water containing high concentrations of radioactive materials, but no leaks have been found in them.
Some of the contaminated water that has accumulated in the side ditches is believed to have flowed through a drainage ditch to an enclosed harbor in the sea after rain fell on the night of March 3, the company said.
According to TEPCO, its workers took water samples from the side ditches on March 3 and detected 1,900 becquerels of beta ray-emitting radioactive materials per liter.
The water levels in the tanks were unchanged.
Monitoring equipment installed on a downstream portion of the drainage ditch showed radioactivity levels of about 100 becquerels or lower on March 3, the same as on conventional days.