Fukushima Daiichi NPS Prompt Report 2014

Fukushima, February 25, 2014 -Recognizing that improvement needs to be made in the reliability of the sampling and testing of water for radioactivity at the Fukushima Daiichi nuclear power station, the Tokyo Electric Power Co. (TEPCO) on February 24 announced that it will ask domestic and internationally recognized organizations in the field, to crosscheck the analysis results, and to review TEPCO's measurement methods from both a technical and management perspective.

Commenting on the decision, TEPCO President Naomi Hirose said, "Public confidence in our reports on radiation levels is essential to everything we are doing in the decontamination and decommissioning of Fukushima, as well as in our overall nuclear power program. We are committed to doing whatever is necessary to restore that confidence and the integrity of the information we provide."

The review by independent entities to crosscheck sampling and testing results and review measurement methods was a recommendation of the group of international experts that has been advising TEPCO in the aftermath of the accident at the plant following the March 2011 earthquake and tsunami.

"Counting loss" issues identified

It also follows the company's confirmation earlier this month that "gross beta" density in water samples (density of the total amount of beta nuclides, such as strontium90, which emit beta rays) taken in the period between April and September 2013 was significantly under-counted, apparently as the result of a series of testing errors. These errors, occurred during a time when the number of the samplings rapidly increased as the result of a series of events since last April, including groundwater reservoir leakage and a major leak from a storage tank.

On February 24, TEPCO has published a list of 164 samples for which it believes radiation was undercounted. The company is currently re-analyzing the data and expects to publish revised radiation levels soon after fixed. None of these involved seawater sampling, and seawater testing has consistently found no threat to human health.

The measurement errors were halted in October 2013, at which time human resources were strengthened and manuals were clarified to ensure the correct testing procedures.

About TEPCO
Tokyo Electric Power Company, Inc. (TEPCO) is Japan's largest power company, supplying energy to the greater Kanto area, including Japan's two most populous cities, Tokyo and Yokohama. Its 35,000 employees are committed to providing safe, reliable power to its 28.8 million customers, diversifying energy resources to ensure sustainability, and contributing to economic growth while fully meeting its responsibilities after the Fukushima Daiichi accident.