Leaks found in the Fukushima ice wall

21 January 2020

Ice wall at Fukushima Daiichi (Credit: Tepco)Coolant has been found leaking at four locations from pipes in the underground wall of frozen soil surrounding reactor buildings at Japan's Fukushima Daiichi nuclear power station.

Tokyo Electric Power Co (Tepco) confirmed that some 20 cubic meters of the coolant had leaked from the pipes.

It said the coolant liquid contains calcium chloride, commonly used as a snow-melting agent, but that it is not an environmental contaminant.  

Tepco noticed the leak problem in late 2019 when the volume in a coolant tank dropped abnormally.

Workers examined the ice wall piping and found leaks in the joints in the pipes between the unit 2 and unit 3 reactor buildings.

The company is poised to investigate the cause of the leaks and replace the problematic parts.

Tepco ordered the construction of the ice wall in May 2013. The 1.5km long wall operates by circulating a coolant with a temperature of minus 30 degrees Celsius through 1568 pipes that extend to a depth of 30m  below the surface.

The soil around the pipes freezes to stop groundwater from flowing into the reactor buildings where it becomes contaminated. The ice wall started operation in March 2016.


Photo: Schematic of the ice wall at Fukushima Daiichi (Credit: Tepco)



Privacy Policy
We have updated our privacy policy. In the latest update it explains what cookies are and how we use them on our site. To learn more about cookies and their benefits, please view our privacy policy. Please be aware that parts of this site will not function correctly if you disable cookies. By continuing to use this site, you consent to our use of cookies in accordance with our privacy policy unless you have disabled them.