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Japan soon to start making ice wall around groundwater at Fukushima nuclear plant

Japan Tries Ice Wall to Stem Radiation  Planned Frozen Barrier to Hold Back Water Contaminated by the Stricken Fukushima Daiichi Nuclear Plant WSJ, By  MARI IWATA   NARAHA, Japan—The idea of freezing ground to block the flow of water has been around for more than a century, but never has it been tried on the scale Japan plans at its stricken nuclear plant to hold back water contaminated by radiation.

As early as next month, workers are set to start installing pipes for a 1.5-kilometer-long and 30-meter-deep subterranean ice wall around four reactors of the Fukushima Daiichi nuclear plant here…….

The Fukushima effort is unprecedented because of the size of the apparatus—its electricity alone is projected to cost $1 million a month—and the period it is expected to operate. The Fukushima decommissioning is expected to take 40 years or longer.

The ice-wall plan has already met a hurdle. In early March, Tepco sought approval from the Nuclear Regulation Authority, the regulator created after the Fukushima accident, and received an array of questions about how it would control groundwater in and around the reactor buildings during construction……

The regulator expressed concern about an unexpected change in the water route, which could cause a leak of highly contaminated water. Officials said Friday they planned to show the regulator more data demonstrating the procedure was safe.

Even if the ice wall is safely built, maintenance costs would be a burden. “It consumes a huge amount of electric power,” said Ryota Ieiri, an independent construction consultant. The wall might help for a few years, but “Tepco will have to find a more sustainable way,” he said……

Tepco also is trying to pump groundwater away from the reactors and divert it into the Pacific Ocean.

The company has been developing a water-treatment system that is designed to remove all radioactive materials from water except for tritium, which is seen as less harmful. But Tepco has yet to show the system can treat the huge quantities of water already in the tanks.

Under its current road map, Tepco aims to start construction of the underground freezing pipes next month and finish around April 2015, at a cost of around $460 million.

Without the ice wall, the company is worried it may run out of room to store contaminated water. The site already has about 1,000 tanks storing more than 400,000 tons of contaminated water.

New tanks are set to increase capacity to about 800,000 tons, but after that, “there won’t be much space left,” said Tatsuya Shinkawa, decommissioning director of the Ministry of Economy, Trade and Industry. http://online.wsj.com/news/articles/SB10001424052702304547704579566374258768990?mg=reno64-wsj&url=http%3A%2F%2Fonline.wsj.com%2Farticle%2FSB10001424052702304547704579566374258768990.

May 17, 2014 - Posted by Christina Macpherson | Fukushima 2014