February 15, 2016

http://www3.nhk.or.jp/nhkworld/english/news/nuclearwatch/20160215.html

TEPCO Revises Water-Diversion Plan

Engineers at the crippled Fukushima Daiichi nuclear plant have drafted a new plan to deal with the buildup of contaminated water. And they've presented the revised method -- of creating an underground wall of frozen soil -- to nuclear regulators.

The plant's operator, Tokyo Electric Power Company, has already installed a system to circulate coolant and freeze soil around the reactor buildings.

The idea is to prevent the flow of groundwater into reactor buildings, where it could become radioactive.

TEPCO officials had planned to start freezing a barrier above the reactor buildings. But regulators were concerned that tainted water in those buildings could leak into the groundwater if the level inside the frozen wall drops too much.

So TEPCO officials decided to freeze the lower wall first, and then gradually freeze the higher wall.

They say it will take eight months to complete. They had originally aimed to have it finished by next month.