2013年８月26日時点
Aiming at fundamentally solving the contaminated water problem, we will take the following three measures for the purposes of “stopping outflow into the ocean”,
“suppressing increase of the contaminated water and preventing outflow into the port” and “stopping inflow of groundwater into the reactor buildings, etc”, for the next 2 to 3 years.
(1) Sea-side impervious wall
Unit 1
(2) Land-side impervious wall (by the soil freezing method)
(3) Pumping up through sub-drains
Impervious wall
• At the sea side of the bank protection, the construction was started in May 2012, which is scheduled to complete in September 2014.
* This requires pumping up of water to be stopped by the impervious wall and accumulated. We plan to solve this problem by installation of pump wells.
Measures against Contaminated Water/Outlines of Fundamental Measures
• Increase of contaminated water due to inflow of groundwater into the buildings can be suppressed by installation of the impervious wall around the buildings.
• Water level management will be conducted in order to prevent outflow of accumulated water from inside the buildings.
• Inflow of groundwater into the buildings will besuppressedby restoring sub-drains and pumping up groundwater around the buildings through the sub-drains.
• Restoring sub-drainsdeeper in the mountain side and pumping up groundwater through such sub-drains is more effective for reduction of the amount of groundwater that flows into the bank protection area.
<Steps of building a soil-frozen wall>
Measure (1) Measure (2)
Measure (3)
Schematic view illustrating the fundamental measures
Unit 2 Unit 3 Unit 4
As of August 26, 2013
“Stopping outflow into the ocean” --- Installation of a sea-side impervious wall. [Causing no leaks]
“Suppressing increase of contaminated water and preventing outflow into the port” --- Installation of a land-side impervious wall (by the soil freezing method).
[Keeping away from contamination] [Causing no leaks]
“Stopping inflow of groundwater into the reactor buildings, etc” --- Pumping up groundwater through sub-drains. [Keeping away from contamination]
Impervious wall
Existing bank protection
Landfill Permeable layer
Permeable layer Low-permeable layer Low-permeable layer
Measure (1) “Stopping outflow into the ocean” --- Installation of a sea-side impervious wall
Measure (2) “Suppressing increase of contaminated water and preventing outflow into the port” --- Installation of a land-side impervious wall (by the soil freezing method)
Hole drilling Embedment of freezer pipes
Circulation of coolant (formation of frozen soil) Circulation of coolant
Freezer pipes Frozen soil Frozen soil
Measure (3) “Stopping inflow of groundwater into the reactor buildings, etc” --- Pumping up groundwater through sub-drains.
Pumping up of water
Pumping up
of water Pumping up
of water
Pumping up of water Reactor building
Turbine building
Seawater surface Drainage
Groundwater level
Pump well
Sub-drain
Keeping water away from the contamination sources
Sub-drain
Groundwater drain
