Cleaning up tunnels

 January 4, 2013

TEPCO to clean up Fukushima plant's tunnels

http://www3.nhk.or.jp/nhkworld/english/news/20140104_18.html 

The operator of the crippled Fukushima Daiichi nuclear plant is preparing to begin cleaning underground tunnels at the site after freezing the mouths of the tunnels.

The tunnels are believed to be one of the sources of radioactive materials that are polluting the groundwater at the facility on a large scale.

Tokyo Electric Power Company plans to block the flow of tainted water between the damaged buildings and the tunnels.

Workers will start burying pipes in the ground to carry refrigerants in January. They plan to begin draining the contaminated water from the tunnels in April after the freezing work is completed.

The operator will also begin testing a plan to freeze soil over a large area.

The eventual goal is to surround the reactor buildings and other facilities with walls of ice to prevent fresh ground water from seeping in beneath the facilities. A large amount of highly radioactive water has accumulated beneath the plant.

As for the decommission of the reactors, TEPCO will set up radiation monitoring equipment at various hot spots on the floors of reactor buildings this month. The readings will be used to support the decontamination work by robots that will follow.

TEPCO officials say they will also study how to remotely locate and repair holes in the reactor containment vessels. The vessels were broken in the nuclear accident.