NHK, May 30, 2015 (emphasis added): Record levels of radioactivity in plant’s port — The operator of the damaged Fukushima Daiichi nuclear plant says it has found record-high levelsof radioactive water in the facility’s port. It says the high levels are due to a leak… They later detected about 22,000 becquerels of beta ray-emitting substances per liter of water in a [ditch]… the channel was around 6,600 becquerels per liter. That’s more than 200 times higher than the figure recorded on Wednesday. TEPCO officials took samples of seawater from 4 locations in the port… 190 and 320 becquerels of radioactive substances per liter. The figure is the highest ever recorded in the port.

TEPCO Press Release (translation via Microsoft), May 29, 2015: Based on article 62 of the law on the regulation of nuclear source material, nuclear fuel material and reactors… contaminated water… spilled into the harbor… and specified nuclear fuel material regulations article 18 No. 11 “when contaminated withnuclear fuel or nuclear fuel material was leaked outside the administrative area”… we deem appropriate.

Previous report from NHK, May 29, 2015: Radioactive water leaks at Fukushima Daiichi –  

The operator of the crippled Fukushima Daiichi nuclear plant says workers have found a leak of comparatively highly radioactive water at the plant’s site. It says the water flowed into the plant’s port… They said they detected about 1,200 becquerels per liter of beta ray-emitting substances from water taken from the channel on Thursday. That figure was 40 times the level the previous day. They said the figure rose to a maximum of 1,400 becquerels on Friday. The officials believe the leakage continued over the two days…

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