On 5 February 2014, the Nuclear Regulation Authority (NRA) of Japan provided the IAEA with an?update?on radioactivity in seawater at TEPCO's Fukushima Daiichi Nuclear Power Station (NPS).
This update on the daily monitoring by TEPCO of seawater near Fukushima Daiichi NPS indicates that the concentrations of all radionuclides (i.e. Cs-134, Cs-137, total Beta and H-3) were relatively stable from 27 January to 2 February 2014 at the sampling points T-1 and T-2-1. The sampling points T-1 and T-2-1 near the Fukushima Daiichi NPS are sentinels to assess effects on the environment by incidents including a leakage of contaminated water. The NRA has been closely observing the results of TEPCO's monitoring of seawater at these sampling points.
The NRA also provided an update on the?sea area monitoring?results for radioactivity obtained from sea water samples taken at a distance of two to 200 kilometers from TEPCO's Fukushima Daiichi NPS.
TEPCO has also announced the decommissioning of Unit 5 and 6 of the Fukushima Daiichi NPS as of 31 January 2014. The formal application to decommission the two Units was submitted by TEPCO on 18 December 2013 to the Ministry of Economy, Trade and Industry in accordance with Article 9, paragraph 1 of the Electricity Business Act. For more information on this issue please refer to TEPCO's announcement,?Decommissioning of Units 5 and 6 at Fukushima Daiichi Nuclear Power Station.
In addition, based on an investigation, TEPCO has provided some images and videos that confirmed cracks in the "deformed fuel assemblies" in the Unit 4 Spent Fuel Pool. (Visuals can be accessed?here?and?here).
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