From the Report of the IAEA regarding Radioactive Water at Fukushima:
While the IAEA is recognizing the usefulness of the large number of water treatment systems deployed by TEPCO for decontaminating and thereby ensuring highly radioactive water accumulated at the site is not inappropriately released to the environment including the adjacent Pacific Ocean, the IAEA team also notes that currently not all of these systems are operating to their full design capacity and performance. ….The IAEA team is of the opinion that the present plan to store the treated contaminated water containing tritium in above ground tanks, with a capacity of 800,000 m 3 , is at best a temporary measure while a more sustainable solution is needed. Therefore the present IAEA team reiterates the advisory point of the previous decommissioning mission: “The IAEA team believes it is necessary to find a sustainable solution to the problem of managing contaminated water at TEPCO’s Fukushima Daiichi NPS.
This would require considering all options, including the possible resumption of controlled discharges to the sea. TEPCO is advised to perform an assessment of the potential radiological impact to the population and the environment arising from the release of water containing tritium and any other residual radionuclides to the sea in order to evaluate the radiological significance and to have a good scientific basis for taking decisions. It is clear that final decision making will require engaging all stakeholders, including TEPCO, the NRA, the National Government, Fukushima Prefecture Government, local communities and others”.
From the IAEA report Released on May 14, 2015 MISSION REPORT IAEA INTERNATIONAL PEER REVIEW MISSION ON MID-AND-LONG-TERM ROADMAP TOWARDS THE DECOMMISSIONING OF TEPCO’S FUKUSHIMA DAIICHI NUCLEAR POWER STATION UNITS 1-4 (Third Mission) Tokyo and Fukushima Prefecture, Japan 9 – 17 February 2015