A Google Maps aerial view of the four Fukushima reactors surrounded by Tepco's proposed dimensions for the ice wall.
Japan this week announced its intentions to build an ice wall surrounding the damaged Fukushima nuclear plant. The hope is that this frozen barricade will keep leaking radioactive water from finding its way into the surrounding environment and the Pacific Ocean.
The problem for Fukushima is two-fold. One is dealing with fresh water that's continually pumped into the plant's reactor cores to keep them cool, water that's later stored on site in leaky tanks. That water is also at risk of leaking out through the main reactor site and entering underground systems.
The other problem is the fact that water flowing underground from nearby mountains can penetrate the Fukushima site. That water picks up radioactivity and carries it off elsewhere, which is both dangerous and difficult to control. But by freezing the ground underneath the reactors, officials hope to contain leaks and stop water from seeping in in the first place.
As Alexis Madrigal pointed out, this plan sounds like something out of a supervillain’s notebook or even some movie that Mystery Science Theater 3000 might mock. But ice walls have been used successfully for many years, especially in mining.
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