The nuclear meltdown in March 2011 of the Fukushima Daiichi Nuclear Power Plant, for the company Tokyo Electric Power Company (TEPCO), following the devastating earth quakes and tsunamis continues to wreak havoc on the environment and the people living closest to the area.
As of 10 February 2014 30,000 people had evacuated the area and 15, 884 died due to the earthquake and tsunami.
A Japanese newspaper recently reported that about 90% of the plant’s workers fled following the nuclear breakdown, an account that differs from Tepco’s statement that the workers were told to temporarily stay away. A full cleanup of the area is expected to take decades.
In an effort to stem the flow of radioactive water into the Pacific Ocean the construction of an ice wall began this week. Although this technology has been used on a smaller scale with the construction of tunnels and near ports, never has it been tried on a project this massive and complex.
Experts are skeptic, such as former US Nuclear Regulatory Commission Chairman Dale Klein, who told Kyodo News “No one has built a freeze wall this long for this period of time. Typically, you build a freeze wall for a few months.”
Klein urges TEPCO to seek the advice of experts in the US and Britain who have managed water and decontamination efforts at former military sites. Former British Atomic Energy Authority Chairwoman Barbara Judge also expressed doubts. Masashi Kamon, a professor emeritus at Kyoto University told Japan News “There is a mountain of challenges, such as possible corrosion of frozen pipes and costs of electricity. They should discuss measures that would combine other methods, such as one using clay.”
The ice wall, which will cost about half a billion dollars, will be created from the moisture in the ground which can be frozen. Holes will be dug every three feet for a mile and then pipes put in. Chilled saltwater will be run through the pipes as it freezes at a lower temperature than freshwater. Because of this the soil is easier to freeze, and thus an impermeable wall can be created. This method is chosen over other materials such as steel, because metal can degrade over time. The wall has an estimated seven-year lifetime, which would give TEPCO time to repair cracks in the turbine and reactor buildings and block the influx of groundwater.
This underground ice wall around the melted-down nuclear reactors is designed to stop hundreds of tons of radioactive groundwater from leaking into the ocean. Though the incident happened in 2011, this project is still necessary because the reactors still have hot nuclear fuel inside of them and workers have to put water into them to keep them cool. The reactors leak and because they are extremely radioactive, they can only be accessed by robots.
TEPCO said a robot sent to Unit 1 of the wrecked plant discovered a source of the water leaks. Until this leak can be plugged, water must be kept pumping out and filtered to remove radioactivity. As much as 1.5 metric tons of water leak from Unit 1 every hour or almost 10,000 gallons a day according to TEPCO estimates. A single exposure to the radioactive material could kill a person within a few weeks, according to the World Nuclear Association.
Besides the ice wall, wells have been dug and groundwater has been pumped out. This method only takes care of ¼ of the 400 tons going through the site. Holding tanks for groundwater from the area between the mountains and ocean are filling up fast.
The expected date of completion for the wall is March 2015, and several months after that the freezing process will be completed. Operating costs and electric power needed to keep the ice wall frozen are expected to be enormous.