Japan announces further Fukushima containment

The Japanese government has announced a series of measures to deal with on-going contamination of groundwater at the Fukushima nuclear power plant. These include sinking frozen soil walls around the perimeter of the plant, lowering groundwater levels upstream of the facility and paving the surface of the contaminated area with asphalt.

The Japanese government has said it will fund the most urgent measures, including the frozen soil wall. The budget for this work has been put at JPY 47 billion (US$ 470 million).

Soil freezing involves sinking boreholes into the ground and then circulating coolant through them to create a contiguous cut-off wall. With a total length of some 1,000 m and a depth of 27 m, the project is thought to be the largest ever application of soil freezing.

Attempts to contain contamination at around the Fukushima plant, which was damaged beyond repair in the 2011 earthquake and tsunami, have already seen the construction of impermeable sodium silicate cut-off-walls on the sea-side of the plant. Newly announced measures include the construction of additional storage tanks for contaminated water and the paving of the surface of the contaminated area to prevent the ingress of rainwater. The paving is expected to start in October.