On 16 April 2014, Japan provided the IAEA with?information?about the accidental transfer of contaminated water from the Central Waste Building to the Incineration Building, both located onsite at TEPCO's Fukushima Daiichi Nuclear Power Station (NPS), and which was reported on 13 April 2014. None of this water was reported to have leaked outside.
TEPCO has provided a bit more detailed figure of the configuration?here?and?here.
TEPCO also provided information on a very minor leak?here.
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