Japan plans to stop leaking radioactive groundwater at Fukushima with an underground wall of ice. Here’s how it would work.
By Peter Fairley on August 30, 2013
WHY IT MATTERS
Contaminated groundwater remains a huge problem at Fukushima.
Japanese officials desperate to contain an ever-growing crisis at the Fukushima nuclear power station are looking to use artificial permafrost to stop radioactive water from leaking. The idea is to build a mile-long wall of frozen earth around Fukushima’s toxic reactor buildings to stem the groundwater contamination; the most experienced specialists in the field say the plan should work.
The Japanese firms involved appear to be taking a go-it-alone approach. Two weeks ago, a top official at Tokyo Electric Power (Tepco) signaled that the utility behind the Fukushima disaster would seek international assistance with the Fukushima water contamination crisis. But experts at U.S.-based firms and national labs behind the world’s largest freeze-wall systems—and the only one proven in containing nuclear contamination—have not been contacted by either Tepco or its contractor, Japanese engineering and construction firm Kajima Corp.
One of these experts is Elizabeth Phillips, who managed the installation of a 300-foot-long, 30-foot-deep freeze wall to isolate radioactive waste at the U.S. Department of Energy’s Oak Ridge National Laboratory in Tennessee in 1996 and 1997. While freeze walls are commonly used to hold back groundwater to facilitate excavations at construction sites and mines, this case calls for specialized expertise, she says. “You need to make sure that whoever is doing it is analyzing everything that can go wrong,” says Phillips. “You should go with someone who has done it before.”