Work has finally begun to freeze the soil around four damaged reactors at the Fukushima Daiichi nuclear power plant. Engineers are trying to reduce the buildup of contaminated water at the site.
Tokyo Electric Power Company, or TEPCO, the owner of the plant, started the work on Thursday, after the Nuclear Regulation Authority gave the go-ahead. It took TEPCO about two years to install the system.
At around 11:20 AM, equipment began sending refrigerant liquid of minus 30 degrees Celsius flowing into pipes driven into the ground around the reactor buildings.
TEPCO says it will freeze soil in phases, first, on the downstream side of the reactors, using 1,000 of the 1,700 underground pipes. TEPCO says it will take about 45 days for the ice wall to generate effects.
Then they will gradually freeze upstream while monitoring groundwater levels. This is to prevent the ice wall from lowering the levels too much and causing radioactive water to leak from the reactor buildings.
Officials say that by summer, the wall, together with other measures, will reduce the daily flow of groundwater into the reactor buildings from 400 tons to about 90 tons. They say the flow will fall to about 50 tons when the wall is complete.
The government’s Chief Cabinet Secretary, Yoshihide Suga, said on Thursday that the government hopes to quickly see a drop in the flow of groundwater into the reactor buildings.
He said preparations have been carried out with much caution, including repeated tests of the ice wall technology. He said he wants the work to be done on a safety-first principle.
Source and image: NHK