Fishermen in Fukushima Prefecture slammed Tokyo Electric Power Co. on Wednesday after it emerged that water containing cesium and other radioactive isotopes has been draining into the Pacific near the Fukushima No. 1 plant and that Tepco did nothing to prevent it despite learning of the leak last May.
“I don’t understand why (Tepco) kept silent even though they knew about it. Fishery operators are absolutely shocked,” Masakazu Yabuki, chief of the Iwaki fisheries cooperative, said at a meeting with Tepco officials.
Local fishermen have already given Tepco approval to dump groundwater into the ocean before it becomes tainted, to reduce the volume of water stored in tanks at the site. The operator is now doing this, pumping water from wells, monitoring it and piping it into the ocean.
The latest incident threatens to delay a second round of approval that Tepco wants the fishermen to provide.
The utility admitted Tuesday it failed to disclose leaks of rainwater containing radioactive substances from a drainage ditch at the stricken plant even though it was aware of high radiation in the water last spring.
The ditch receives runoff from the roof of the No. 2 reactor building, which is highly contaminated with radioactive substances such as cesium.
Tepco has said it recorded 29,400 becquerels of radioactive cesium per liter in water pooled on the rooftop.
The water also contained 52,000 becquerels of beta-ray-emitting radioactive substances such as strontium-90. It also detected some 1,050 becquerels of radioactive cesium and 1,500 becquerels of beta ray-emitting radioactive materials per liter near an outlet leading to the sea.
Tepco said there is no major change in the concentration of radioactive substances in seawater it sampled about 1 km from the drainage outlet.
Meanwhile on Sunday, Tepco reported water contaminated with high levels of radiation was flowing into the ocean at the plant’s port through another drainage ditch.
Yuji Moriyama, a Tepco spokesman said the utility did not disclose the information because there is no evidence of environmental impact.
“We were aware that the levels of radioactive materials around the drainage ditch were higher than other places,” Moriyama said, adding that they have been investigating the sources of contamination since last spring.