Fukushima plant frozen soil may be partly melted

The operator of the damaged Fukushima Daiichi nuclear power plant says part of an underground frozen soil wall around reactor buildings of the facility may have melted and that it is considering fixing the structure.

Tokyo Electric Power Company pours coolant at minus 30 degrees Celsius into pipes of the wall.

The structure is designed to block groundwater from flowing into the buildings, which are contaminated by radioactive substances. When the utility began to freeze the soil in March 2016, 500 tons of groundwater had been contaminated daily.

TEPCO says the temperature in the wall rose to 13.4 degrees Celsius on November 18 on the mountain side of the No.4 reactor building. The temperature had been above freezing since mid-September.

The firm says it also found water near part of the wall that should have been frozen. It says underground spring water may have warmed the area and melted part of the soil.

TEPCO says it plans to begin installing steel pipes and boards to prevent possible inflow of groundwater into the frozen soil as early as next month.

It says it has found no change in the water level in the wall near the buildings, and that the structure has maintained its functions as a whole.