Proposals to sort out problem of contamination from radioactive water

Steps to halt increase of radioactive water at Fukushima plant studied

http://mainichi.jp/english/english/newsselect/news/20130427p2g00m0dm007000c.html 

TOKYO (Kyodo) -- A government-appointed panel of experts on Friday started studying ways to prevent more radioactive water from accumulating at the Fukushima Daiichi nuclear power plant, including a plan to embed walls around the damaged reactor buildings to stop groundwater from entering.

About 400 tons of groundwater seep into the plant every day, flowing into the lengthy and complicated water circulation loop that keeps the plant's damaged reactors cool. In the process, the groundwater becomes contaminated.

Plant operator Tokyo Electric Power Co. has so far dealt with the situation by increasing the number of water storage tanks at the site. It has also built a dozen wells to pump out part of the groundwater that enters the reactor buildings as it flows from the mountainside to the ocean-side.

But the panel, also joined by officials of the government and TEPCO, hopes to find a more fundamental solution because the utility could eventually run out of water storage capacity.

Some proposals were presented during the meeting of the panel members Friday, such as building an underground wall around reactor buildings by using a clay-like material.

TEPCO once considered building a wall on the mountain side of the reactor building after the plant was crippled by a huge earthquake and tsunami in March 2011, but it abandoned the idea because of the risk that contaminated water accumulating inside the reactor buildings could flow onto the soil outside.

The problem of keeping massive amounts of radioactive water at the plant has recently drawn renewed attention after TEPCO found some underground water storage pools containing contaminated water had leaked and had to find a secure storage space.