The mission of Tokyo Electric Power Company Holdings (TEPCO), and my personal mission, is to safely decommission the damaged Fukushima Daiichi nuclear power station and thereby contribute to the revitalization of Fukushima.

In performing this important work, we are guided by the principle of balancing the recovery of Fukushima with the decommissioning of the Fukushima Daiichi nuclear power station, doing everything possible to mitigate the risks as we progress. Since the accident on March 11, 2011, we have stabilized the site and alleviated many of its crisis aspects.

Most significantly, we have been making efforts to improve the working environment by reducing the contamination on the site due to the accident. About 4,000 workers are currently engaged at Fukushima Daiichi. The average monthly radiation dose for those workers has been reduced from 21.55 mSv (2,155 mrem) immediately following the accident to 0.3 mSv (30 mrem).

The accident at Japan's Fukushima Daiichi nuclear power plant on March 11, 2011, has sparked many safety improvements in the nuclear industry over the past decade. Lessons from the accident and its aftermath will influence firms and regulators as they consider the future design, construction, operation and decommissioning of nuclear reactors.

An American Nuclear Society webinar, “Nuclear News Presents: A Look Back at the Fukushima Daiichi Accident,” held yesterday was attended by more than 1,550 viewers and generated about 150 questions to the panelists. The attendance was the largest ever for an ANS webinar.

The panelists were Mike Corradini, emeritus professor, University of Wisconsin; Dale Klein, former chairman of the U.S. Nuclear Regulatory Commission; Joy Rempe, principal, Rempe and Assoc. LLC; Lake Barrett, senior advisor, Tokyo Electric Power Company and Japan’s International Research Institute for Nuclear Decommissioning (IRID); and Paul Dickman, senior policy fellow, Argonne National Laboratory.

The webinar’s recording and slides are available here, along with an e-version of the March issue of Nuclear News, which features a cover story on the Fukushima Daiichi accident.

The Fukushima Daiichi site before the accident. All images are provided courtesy of TEPCO unless noted otherwise.

It was a rather normal day back on March 11, 2011, at the Fukushima Daiichi nuclear plant before 2:45 p.m. That was the time when the Great Tohoku Earthquake struck, followed by a massive tsunami that caused three reactor meltdowns and forever changed the nuclear power industry in Japan and worldwide. Now, 10 years later, much has been learned and done to improve nuclear safety, and despite many challenges, significant progress is being made to decontaminate and defuel the extensively damaged Fukushima Daiichi reactor site. This is a summary of what happened, progress to date, current situation, and the outlook for the future there.

The black star represents the epicenter of the February 13 earthquake. Image: USGS

There has been no off-site impact from the February 13 earthquake that struck off the east coast of Japan near the Fukushima Daiichi nuclear power plant, Tokyo Electric Power Company (TEPCO) reported on February 19. The earthquake, however, has caused a water leakage from two of the site's primary containment vessels (PCVs).

A nuclear alert order was issued by the plant about 20 minutes after the earthquake, and the water treatment and transfer facilities were shut down. Inspections after the event revealed no anomalies and the nuclear alert order was rescinded on February 14.

The nuclear plant in Fukushima Prefecture in northeastern Japan is now undergoing decommissioning.

Decommissioning work in parts of the Fukushima Daiichi plant in Japan has been delayed after engineers discovered that sandbags placed in the basements of buildings near Units 1 and 3 were found to contain excessive radiation levels. Tokyo Electric Power Company (TEPCO) operates the plant and is in charge of the decommissioning efforts following the accident caused by the earthquake and tsunami on March 11, 2011.