On 21 May 2014, Japan provided the IAEA with an?update?to current information on radioactivity in seawater at TEPCO's Fukushima Daiichi Nuclear Power Station (NPS).

The update shows that TEPCO has completed discharging 561 tonnes of groundwater to the ocean by means of the groundwater bypass system. The discharging started at UTC 1:25 and was completed at UTC 3:42 0n 21 May 2014. Current information on radioactivity in seawater shows that all radionuclides (i.e. Cs-134, Cs-137, total Beta and H-3) have remained low and stable from 13 May 2013 to 12 May 2014. These sampling points near Fukushima NPS are sentinels to assess effects on the environment by incidents including a leakage of contaminated water.

The NRA also provided an update on the?sea area monitoring results?for radioactivity obtained from sea water samples taken at a distance of 2 to 200 kilometres from TEPCO's Fukushima Daiichi NPS.