for Japanese


1 December, 2015

TEPCO to Dismantle Top of Unit 2 Reactor Building at Fukushima Daiichi

On November 26, the Tokyo Electric Power Co. (TEPCO) released a report on the progress of decommissioning work at the Fukushima Daiichi Nuclear Power Plants.

The incineration facility for miscellaneous solid material wastes at Fukushima Daiichi

Unlike the other three units, Unit 2 did not suffer a hydrogen explosion, so the upper operating floor of its reactor building remained intact. TEPCO had considered various options for dismantling and remodeling the top of the building before removing debris from the reactor, as well as spent fuel from the pool. It finally concluded that dismantling everything above the top floor was desirable from the viewpoints of maintaining work safety, mitigating its influence outside the Fukushima Daiichi site, and reducing risk.

TEPCO is now mulling over two different ways to remove the spent fuel and fuel debris: (1) using a common container for both, with a single container installed in the upper part of the operating floor of the reactor building, and (2) using two separate containers, one for the spent fuel and the other for the debris.

The power company had drawn up and compared several plans, each with a differing extent of dismantling to be carried out. Eventually, it determined that the best option would be to dismantle the entire upper portion of the building using either of the above two concepts. Even after the entire upper part of the building is dismantled, the increased amount of radioactive materials to be released from the four reactor buildings (Units 1 to 4) would still be within the scope of variations currently experienced.

TEPCO will now develop a detailed work plan, construct a mock-up and test the plan, initiating work based on that evaluation. It aims to decide on a removal plan for the spent fuel and debris—that is, whether to use one or two containers—in the first half of FY17 (April to September 2017). To that end, the company will begin dismantling and structural work on the building during the current fiscal year, which ends in March 2016.

According to the medium-term and long-term roadmap toward decommissioning for Fukushima Daiichi, spent fuel is to start being removed from the spent fuel pool of Unit 2 in FY20 (beginning in April 2020).

Meanwhile, as for measures to deal with the contaminated water emanating from the plant, TEPCO confirmed that the concentration of radioactive materials in the port seawater had started to decline after a shielding wall on the ocean side of the Fukushima Daiichi NPPs was completed on October 26. The data show that the wall is starting to be effective.

As for miscellaneous solid material waste, including used protective garments, TEPCO has finished constructing an incineration facility for them, and began tests using simulated waste on November 25. The power company will now carry out additional testing using actual contaminated waste. It hopes to start full operation by next March 31, the end of the current fiscal year.


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)