Fukushima’s ‘Ice Wall’ Switched On: Will It Stop Contaminated Water Leaks?

What’s being called an unprecedented “ice wall” might finally stop the irradiated water seeping out from the Fukushima daiichi nuclear power plant. The novel solution could provide some relief for people working to finally decommission the plant, which was fatally damaged in the 2011 earthquake and tsunami that hit Japan.

According to the Portland Press Herald, the operator of the broken plant, Tokyo Electric Power Co., switched on the ice wall refrigerator system on Thursday. It’s not entirely certain to work, tests over the summer had mixed results, but there are few other solutions for the Fukushima plant’s excessive wastewater.

The problem stems from melted nuclear cores in three damaged reactor buildings. The cores are in constant risk of overheating again, so the operator has to pump in water as a coolant. But the buildings are damaged, so the water leaks out.

The contaminated water finds its way into the ground water, forcing the operator to treat massive amounts of radiation. So far, 800,000 tons of water, to be exact. The Fukushima plant grounds have 1,000 full water tanks (each tank holds about 112 Olympic-sized pools worth of water according to the World Science Festival). Those containers are being constructed everywhere from parking lots to lawns and, as of early 2014, covered about 42 acres of space.

Those Fukushima tanks are also a safety risk. In October of 2013, one broke and possibly leaked radiation into the Pacific Ocean according to the New York Times.

The treatment of the water is a problem as well. The radioactive particles are small, hard to separate from the water, and once taken out have to be stored much like spent nuclear fuel rods.

The ice wall should end most of the water problem. According to ABC News, the ice wall consists of 1,550 underground refrigeration pipes that are designed to create a 0.9 mile (1.5 km) barrier of frozen soil around four battered reactor buildings, theoretically sealing up any leaks.

The solution has some shortcomings. The pipes run 30 meters underground, roughly the height of a 10-story building, and the system keeps the surrounding soil at negative 22 F (30 degrees C). A system that powerful requires an enormous amount of electricity.

The operator insists that the Fukushima ice wall will stay frozen for two months in the event of a prolonged power outage, but the costs will still be significant.

Another concern is that the ice wall can’t be adjusted quickly in the case of an inflow of water. In 2015, that situation happened, when flood waters from Typhoon Etau swamped the area. As a result, tons of contaminated water from Fukushima flowed into the Pacific Ocean. Bags of irradiated dirt were also swept away according to the Japan Times.

The operator also says the coolant used in the ice wall is environmentally friendly.

The government worked together with Kajima Corp to build the $312 million Fukushima ice wall. The project was delayed because of technical uncertainties, but was completed last month, roughly a year behind schedule.

According to the World Science Festival, full decontamination will take 30 years, because waiting for dangerously radioactive fuel to become harmless is the only sure-fire method. There’s also the issue of removing the fuel rods, which are possibly damaged or corroded. If the Fukushima ice wall is successful, it will be a big step in the right direction for the troubled plant, but the end is still distant.

[Photo by Christopher Furlong/Getty Images]