TOKYO Dec. 5, 2013. -An gradual rise in radiation readings at a test well on the site of Fukushima Daiichi NPS appears to be the result of successful efforts to pump groundwater and divert it from flowing into the ocean, according to the Tokyo Electric Power Co (TEPCO).
Readings at the well site had generally been within the range of 400,000 to 800,000 bequerels per liter of gross beta (total amount of beta nuclides), but had begun rising in the end of October this year. Various efforts to control the flow of contaminated water toward the ocean had been begun on July 8, including the pumping of groundwater from the area in which it was being contained.
On November 28th, the reading at well 1-16, located in this area near Units 1 and 2, rose to 1.1 million bq/l, and on December 2 the reading was 1.3 million bq/l. TEPCO engineers believe this rise is associated with the residual highly contaminated water that leaked out from Unit 2 in April 2011 in the immediate aftermath of the earthquake and tsunami that disabled the plant.
Significantly, no change has been observed in seawater radiation density readings, which TEPCO measures and announces every day. TEPCO engineers and international experts confirm that there is no increased risk to human health or the environment. However, engineers are continuously taking samples at that and other wells to closely monitor radiation levels and will promptly report the results. They are continuing to analyze the results to more precisely determine the cause of the increase.
Lake H. Barrett, a former U.S. Department of Energy official who is acting as an advisor to TEPCO, said: “While the rise in radiation readings is an obvious concern that needs to be carefully monitored, in some respects it is an indication of the success of TEPCO’s concerted efforts to isolate contaminated water and prevent its flow into the sea. The situation warrants continuous monitoring and careful analysis, but there appears no increased level of risk to workers, the public, or the environment.”
For more details on the results of seawater testing, go to http://www.tepco.co.jp/en/nu/fukushima-np/f1/smp/index-e.html
TEPCO, Inc. is a provider of electricity to the Kanto region, which includes Tokyo and Yokohama. The company is headquartered in Tokyo. The Fukushima Daiichi Nuclear Power Station was struck by a tsunami after an earthquake that occurred in March 2011. For more information, please go to http://www.tepco.co.jp/en/index-e.html.