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Fukushima Daiichi NPS Prompt Report 2014

Fukushima Daiichi NPS Prompt Report (May 21, 2014)BYPASS OF CLEAN GROUNDWATER TO OCEAN STARTS

FUKUSHIMA, May 21, 2014-Bypass of clean groundwater around Fukushima Daiichi Nuclear Power Station started, marking a major milestone in the resolution of water management issues, Tokyo Electric Power Co. (TEPCO) announced today.

First discharge of the clean upstream water stored inside the temporary storage tank started at approximately 10:25 AM and finished at approximately 12:42 PM for all 561 tons to be discharged today, the company said.

The water's quality is monitored regularly by independent third parties using safety and environmental standards more stringent than those set by Japanese law.

Naohiro Masuda, the president of the Fukushima Daiichi D & D Engineering Company, an in-house entity within TEPCO focusing on the decommissioning at the site said "We would like to express our sincere appreciation to many parties, including Fukushima Prefecture and members of the fishing industry, for their understanding in the operation of the groundwater bypass, which plays an important role among the countermeasures to suppress the increase of contaminated water. In operating the bypass, we will pay strict attention to the management of the relevant facilities and, in conjunction with analysis by third parties, maintain the water quality to conform to operational targets."

The groundwater bypass, one of several strategies being employed to reduce the accumulation of contaminated water at the plant, aims to intercept clean groundwater as it flows downhill toward the sea, and reroute it safely around the facility. The water is temporarily stored to verify its quality prior to release.

Once in full operation, the groundwater bypass is expected to reduce the amount flowing into the building basements by up to 100 tons per day, a reduction of 25 percent. The bypass will help reduce the volume of water that becomes contaminated and then needs to be cleaned and stored on site. This, in turn, is expected to reduce the burdens on the storage facility by slowing the pace of contaminated water accumulation.

Photos and video of the discharge may be seen at

Full version of President Masuda's comments may be seen at

Basic management policies and operation rules for the system are explained at

<What is groundwater bypass system?>
Simple explanation of the bypass system may be obtained at

Water discharge criteria for the system is explained at

A video explaining the bypass system may be seen at

Groundwater Bypass Plan - For Suppressing Increase of Contaminated Water -

The Groundwater Bypass System



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.
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