for Japanese


7 May, 2015

TEPCO to Begin Tests of Frozen-soil Shielding Walls at Fukushima Daiichi

On April 28, Nuclear Regulation Authority (NRA) approved the beginning of testing of frozen-soil shielding walls at 18 points on the mountainside west of the reactor buildings for Units 1 to 4 at the Fukushima Daiichi Nuclear Power Station, damaged during the March 2011 tsunami.

Cooling instrument at the site

The Tokyo Electric Power Co. (TEPCO) has been working on the walls as one way to deal with the contaminated water coming from the reactors. On April 30, the power company began tests involving some of the coolant pipes.

The frozen-soil shielding walls are to stop the inflow of groundwater coming from the mountainside to the reactor buildings. The inflows of such water have increased the quantities of contaminated water. More than 1,500 pipes will be installed beneath the ground in an area fronting the four reactor units that stretches some 1.5km. Coolant will then be injected into the pipes to freeze the surrounding soil.

The freezing test is being conducted at 18 points (58 pipes) on the mountainside west of the buildings, where it is deemed particularly difficult to freeze the soil due to buried objects and other items, so as to check the response of the system and changes in underground temperature. The portion to be frozen in the test will be approximately 4% of the total intended to be eventually frozen.

The freezing test is expected to continue for several weeks. TEPCO will then start freezing the soil on the mountainside after the NRA officially approves the operation of the system.

The power company will eventually freeze the walls on the seaside as well, thus completely surrounding the reactor buildings with frozen soil. Currently, however, the NRA is examining the installation method on the seaside, where highly radioactive contaminated water has been found in trenches (underpasses for power cables, and so forth).

Consequently, it is unknown when full-scale operation — i.e., the freezing of all the intended shielding walls — may be possible.


This site uses Akismet to reduce spam. Learn how your comment data is processed.

SNS facebooktwitter

NPPs Map


Voices from Nuclear Industry – Contributing to a clean and resilient recovery

3 September, 2020
Voices from Nuclear Industry – Contributing to a clean and resilient recovery03:59

Recent News

26 November, 2020
JAIF Releases Results of Fact-finding Survey of Japanese Nuclear Industry for Fiscal 2019: Some Effects Seen of COVID-19
24 November, 2020
Japan’s Energy Supply and Demand in Fiscal 2019 Shows CO2 Emissions Down for Sixth Year in a Row
24 November, 2020
NUMO Accepts Applications from Two Municipalities to Conduct Literature Surveys, Moving Closer Toward Selecting HLW Final Disposal Site
16 November, 2020
Kyushu Electric Power Starts Operating Facilities at Sendai-1 NPP Designed for “Specific Severe Accident” Response—First Time in Japan
13 November, 2020
Japan’s NRA Approves Changes to Mutsu Recyclable-Fuel Storage Center after Confirming Regulatory Compliance
13 November, 2020
Keidanren Announces New Growth Strategy Supporting Advanced Reactor Development
29 October, 2020
New Prime Minister Suga Enthusiastic for Carbon-Free Society by 2050
16 October, 2020
Government’s Strategic Policy Committee Starts Deliberations toward Revision of Strategic Energy Plan
13 October, 2020
NUMO Accepts Suttsu’s Application for Literature Survey in Selecting HLW Final Disposal Site—First Since Release of Map of Scientific Features
12 October, 2020
Nuclear Power Plant and Reactor Exporters’ Principles of Conduct (NuPoC)