As reported last week, Japan’s Fukushima Daiichi nuclear plant, devastated by a 2011 earthquake and tsunami, is still leaking about 300 tons of water contaminated with several radioactive elements, some of which have been linked to bone cancer, each day into the Pacific Ocean.
The newest idea to contain the leaks is a proposal to create an underground dam by freezing the soil. Vertical pipes would be sunk into the ground about a meter apart and between 20 and 40 meters deep around the unit, and piped full of coolant from above-ground refrigerator units. The construction company that built the plant has been given until March to finish the proposal; the earliest they anticipate building it is July 2015.
Although it sounds bizarre, this artificial permafrost technique has been used since the 1860s for mine, tunnel, and building construction, including currently for the Second Avenue subway in New York City. The greatest objection to its long-term use is the cost of power to keep the ground refrigerated. But Prime Minister Shinzuo Abe has pledged for the first time to take “urgent measures,” rather than leave the cleanup any longer to Tokyo Electric, and this seems to be the best option on the table.
[Image: Flickr user Sharon Mollerus]