The nation's nuclear watchdog exhorted Tokyo Electric Power Co. to do something about the accumulation of tens of thousands of tons of highly radioactive water at the stricken Fukushima No. 1 nuclear plant, calling the situation intolerable.
“We cannot allow the danger of highly polluted water at the plant to continue any longer,” Toyoshi Fuketa, a commissioner of the Nuclear Regulation Authority, said at a July 19 meeting to discuss work on the plant’s decommissioning.
Fuketa urged TEPCO to consider pumping the highly radioactive water or diluting it, citing the risk of spill if another tsunami hits.
About 60,000 tons of water containing extremely high levels of radiation have accumulated in the basements of the No. 1 through No. 4 reactor and turbine buildings.
Water leaking to the basement floors of the facilities after being used to cool melted nuclear fuel at the plant has mixed with underground water flowing there.
The concentration of radioactive cesium is estimated at between hundreds of thousands becquerels and tens of millions of becquerels per liter.
Fuketa said the utility should weigh either pumping or taking measures to reduce radiation levels of polluted water.
NRA’s directive is intended to prevent the leakage of contaminated water into the nearby sea or outside the buildings in the event of a tsunami unleashed by another powerful earthquake.
TEPCO is expected to present the results of its study of steps it could take as early as August.
The company has been trying to reduce the volume of contaminated water by building a frozen underground wall around the reactor and turbine buildings. The frozen soil wall was expected to prevent groundwater from flowing into the plant.
TEPCO started the freezing of the soil in late March, but not all of the wall is in an ice state, with the result that a huge volume of groundwater is still flowing to the nuclear complex.