Contaminated water to be moved to more "reliable" tanks...by June

April 11, 2013

TEPCO to stop using underground tanks at Fukushima plant

http://ajw.asahi.com/article/0311disaster/fukushima/AJ201304110054

THE ASAHI SHIMBUN

Tokyo Electric Power Co. has decided to stop using all the underground tanks to store radioactive water at its crippled Fukushima No. 1 nuclear power plant.

TEPCO President Naomi Hirose told a news conference at the company's Fukushima Revitalization Headquarters in Naraha, Fukushima Prefecture, on April 10 that all of the water in those tanks will be transferred to surface tanks.

"We are deeply sorry for seriously troubling the public and the people of Fukushima (Prefecture)," he said in opening the news conference.

Four of the tanks currently hold 23,600 tons of radioactive water. According to Hirose and other officials, TEPCO will move 7,100 tons of the water to existing surface storage tanks, including one of the plant's filtered water tanks, between next week and early May.

The utility will also build 38 new steel tanks, with a combined capacity of 19,000 tons, and move the remaining 16,500 tons of radioactive water into them between the second half of May and early June.

The company previously only planned to transfer just over 7,000 tons of the water to existing surface tanks.

"I believe the new tanks will allow us a certain leeway in our operations," Hirose said. "We will commit ourselves fully to the task."

Hirose dismissed speculation that radioactive water could be released into the sea.

"That will absolutely never happen," the president said. "There is no change in our policy to use all available means to manage (the water)."

Hirose admitted TEPCO has yet to establish the cause of the water leaks from three of the underground storage tanks and indicated they will likely never be used in the future.

TEPCO to remove all radioactive water from troubled tanks by June

http://mainichi.jp/english/english/newsselect/news/20130411p2g00m0dm031000c.html

TOKYO (Kyodo) -- The operator of the crippled Fukushima Daiichi nuclear power plant on Wednesday unveiled a plan to transfer all the highly radioactive water stored in underground tanks to more reliable containers by the end of June to address the risks of further leaks.

Three of the seven underground tanks have been found to be leaking, and operator Tokyo Electric Power Co. has decided to empty not only those three but another tank as well. The tanks are used to store water for cooling reactors which experienced meltdowns during the 2011 nuclear crisis at the plant. A total of 23,600 tons of liquid will be pumped out by June.

Two of the tanks are not in use, and TEPCO said it will also eventually remove about 3,000 tons of water held in the remaining tank, which is much less contaminated because that water has not been used to cool the crippled reactors.

TEPCO said it came up with the plan because the utility found it can secure enough alternative storage capacity at the site, such as by using existing containers that have room for the water and by installing new tanks.

Economy, Trade and Industry Minister Toshimitsu Motegi told a parliamentary committee earlier in the day that TEPCO should eventually stop using the underground tanks after swiftly removing the contaminated water.

The situation regarding the radioactive water leaks has been worsening since TEPCO earlier this month disclosed the damage, with the number of underground cisterns with problems increasing.

There is speculation there may have been some flaws in the construction process of the containers, all seven of which were built by Maeda Corp.

TEPCO also said it confirmed a small amount of radioactive substances outside the water-containment sheets laid between the No. 1 tank, the latest container found with leaks, and the soil.

At the Fukushima plant, a massive amount of radioactive water is accumulating as a result of continuing water injections into the Nos. 1 to 3 reactors, which experienced meltdowns.

Water once used to cool the damaged reactors is recycled as coolant after radioactive cesium has been removed in a water-processing facility. But the total amount of contaminated water is increasing because the existing water flow allows an influx of about 400 tons of groundwater a day.

To reduce the risk of keeping a massive amount of polluted water at the plant's premises, TEPCO plans to install a new water treatment system capable of reducing various radioactive substances in addition to cesium to an undetectable level.

TEPCO started a trial run of the system in late March, but it will take at least about four months before shifting to full operation, officials said.

To enhance oversight at the plant, which has also recently seen the suspension of its cooling system for spent fuel pools, the Nuclear Regulation Authority said it has decided to increase the number of inspectors at the plant from eight to nine.

NRA Chairman Shunichi Tanaka said during a meeting of regulatory commissioners Wednesday that TEPCO needs to remake its long-term plan for handling radioactive water.

"What is most important is to take measures so that the situation outside the plant's premises will not be affected," Tanaka said.