Fukushima crisis: 'Ice wall' test to begin soon
The feasibility test will start by mid-October at the earliest and will involve driving steel pipes 30 metres deep into the soil near the No.4 reactor building, reported Xinhua.
The pipes will surround a 10 square metre area, initially, the officials said, and liquid calcium chloride at minus 40 degrees Celsius will be injected into the pipes to freeze the surrounding soil.
The test is designed to check whether such an "ice wall" is capable of stopping the flow of contaminated groundwater. The duration of the test period will be five months, said the officials.
Japan's Prime Minister Shinzo Abe, along with other members of the government's nuclear disaster task-force, Tuesday approved the basic plan to construct a 1.4 km-long underground frozen wall around four damaged reactors at the stricken facility.
By creating an ice wall, the government believes that groundwater will be prevented from mixing with coolant water that is becoming contaminated after coming into contact with melted nuclear fuel.
Under its current plans and provided that the tests prove to be successful, the wall will be operational by the end of March 2015, government officials confirmed Thursday.
The government has come under increasing pressure to take a more proactive role in tackling the Fukushima crisis after a series of gaffes by Tokyo Electric Power Co. (TEPCO), including hugely inaccurate reporting of radiation levels, shoddy efforts to patch up a leaking tank responsible for 300 tonnes of toxic water flowing freely into the Pacific, and failing to detect the leak in the first place.