Summary Report

The 3rd IAEA-MOE Experts Meetingon Environmental Remediation

Tokyo, Minami-Soma City, Date City
17 – 21 April 2017

Summary Report
The 3rd IAEA-MOE Experts Meeting on Environmental Remediation

A. Introduction
The 3rd IAEA-MOE Expert Meeting allowed the IAEA team1 to review current progress made with theremediation effort in the off-site areas affected by the accident at TEPCO’s Fukushima Daiichi Nuclear
Power Station. During the meeting, the MOE informed the IAEA team of the achievement of the “fullscale” decontamination in the Special Decontamination Area (SDA) (excluding the Areas where
Returning is Difficult) based on the Decontamination Implementation Plan. The MOE also explainedthat the decontamination in the Intensive Contamination Survey Area (ICSA) was also near completion
as of March 20172.
It was reported by the MOE that the ICSA encompassed 104 municipalities in 8 prefectures (i.e., Iwate,
Miyagi, Fukushima, Ibaraki, Tochigi, Gunma, Saitama, and Chiba) in the beginning (923 as of March2017), and that the SDA encompassed 11 municipalities in Fukushima Prefecture. The ICSA and SDA
are shown in Fig.1 below. During the meeting, the MOE explained, as follows:
the total areas where decontamination was implemented in the SDA included approximately
22,000 houses and approximately 15,700 ha (approximately 8,500 ha corresponding tofarmland, approximately 5,800 ha to forests, and approximately 1,400 ha to roads);
the peak number of evacuees was observed in June 2012 totalling approximately 164,000
inhabitants, in June 2015 this number dropped to approximately 112,000, and by the end of
2016, the number decreased further to approximately 72,000;
it would be estimated that approximately 24,000 people, whose original living areas have been
designated as Areas where Returning is Difficult, still remain evacuated; anda proportion of the evacuees has already resettled in other places and has shown no intention to
return to their original houses.
The meeting covered four topical sessions:session one reviewed the outcomes of the environmental remediation works carried out at theoff-site areas affected by the accident at TEPCO’s Fukushima Daiichi Nuclear Power Station;
session two discussed the lessons learned on remediation based on data collected in Date City;
session three focussed on how to evaluate the effects of the “full scale” decontamination; andsession four addressed how to best share the results from the applied technologies fordecontamination and waste volume reduction with the international community.

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The IAEA team was composed of IAEA staff and international experts.

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In the ICSA area remediation works have been undertaken by the municipalities with the technical and financial
support of the National Government. In the SDA the decontamination efforts were the responsibility of the Ministry of
the Environment (MOE). The Areas where Returning is Difficult are those within the SDA where it is anticipated that
residents will face difficulties in returning for a long time.
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The number of municipalities in the ICSA decreased mainly because the designation of an ICSA has been lifted forsome municipalities.

1Site visits to review the activities on soil-recycling conducted in Minami-Soma City and the incinerationof combustible waste in a dedicated facility in Date City took place during the last day of the week.
This report summarizes the main findings of the IAEA team and some proposals of suggestions to theJapanese authorities for further consideration in progressing the environmental remediation and related
works.

Fig.1. ICSA (as of 31 March 2017) and SDA (as of 1 April 2017)

B. Meeting Results
It was reported by the MOE that the “full-scale” decontamination was completed within the SDA
according to the plans established by the MOE. According to the Act on Special Measures concerning
the Handling of Radioactive Pollution, the target for areas where the projected annual effective dose4
was 20 mSv or above was to “reduce the size of the areas step-by-step but as soon as possible”; and in
those areas where the projected annual effective dose was below 20 mSv, the aim was to “reduce
additional exposure dose rate to 1 mSv per year or less” in the long-term. The MOE explained that theoverall process of remediation was strongly influenced by interactions with stakeholders to facilitate
the return of evacuees to their homes and the provision of sustainable living conditions.
It was also reported that a broad range of techniques were used in the remediation strategies, according
to the specific objects being decontaminated (e.g. houses and buildings, gardens, roads, schoolyards,

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Annual effective dose is subsequently referred to as ‘dose’2

farmlands and forests). These techniques included wiping off roofs and walls, high pressure washing,removal of fallen leaves, topsoil stripping, reverse tillage, etc.
The IAEA team was informed that the total volume of contaminated soil and waste generated fromdecontamination work was estimated to be up to circa 22 million m3. It was explained that, prior to final
disposal, the contaminated soil and waste would be sent to the Interim Storage Facility (ISF) where theywould be managed for a period of 30 years following the start of the interim storage. The MOE has
initiated a programme to investigate disposal options, and is, for example, conducting research on
recycling and volume reduction techniques with a view to reduce the amount of waste going for disposal.
The results presented by the MOE enabled the IAEA team to conclude that significant progress has
been made with the remediation in the offsite areas affected by the accident, and that steady progresson the ISF construction and soil/waste transportation to this facility has been made. As alreadymentioned, the milestone, namely, the completion of the “full-scale” decontamination in the SDA wasachieved by the MOE, and because of this achievement, many municipalities in the SDA have had theirevacuation orders lifted.
It was explained that the remediation process in the ICSA was implemented by the municipalities withthe support of the MOE. In this regard, the accumulated experience and the ways of remediation work
might have differed from municipality to municipality depending on prevailing circumstances in eachof them.
The IAEA team views that it is important for the MOE to continue its efforts to share its experience of
the “full scale” decontamination with both national and international communities through developing
a series of decontamination reports.
The IAEA team has suggested that the MOE, in cooperation with other relevant organizations inJapan, should focus its efforts to develop remediation plans targeting the Areas where Returning is
Difficult in conjunction with the rebuilding of the infra-structure within the SDA. In this regard, it
is important to develop plans for further lowering doses in the SDA following the full scaledecontamination in order to meet the long-term goal of 1mSv per year. The plans should prioritise
the activities and milestones to prepare for repopulation and recovery. Finally, while developing the
2nd decontamination report, the MOE may reach out to international stakeholders to identify the
information that might enhance the completeness of the report. The IAEA team views that the IAEA
could contribute, in this respect, by providing feedback on the MOE’s report during the next IAEAMOE meeting.

For the second session, an official of Date City presented the city’s response and lessons learned
following the accident at TEPCO’s Fukushima Daiichi Nuclear Power Station. It was reported that,
immediately after the accident, the mayor of Date City, with the support of the local community, decided
to use municipality funds to implement immediate remediation works to protect the citizens fromexposure to ionizing radiation and to promote the return of the citizens to their normal lives as soon as
possible. The official of Date City mentioned that the decisions were made in the absence of preestablished laws or guidelines. It was also explained that the creation of the first Temporary Storage
Site took place in October 2011 after an intense process of engagement with the technical experts(invited by Date City) and local stakeholders. At the present moment, there are 50 Temporary Storage
Sites totalling 29 ha in inhabited area.

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According to the presented information, the authorities of Date City and local community came to theconclusion that the removal of the soil was not an objective by itself, but rather one of the possible
remediation techniques. The effectiveness of soil removal in reducing radiation exposure, several years
after the accident was being questioned in the municipality. The distribution of personal passive
dosimeters among the citizens in the city demonstrated that soil removal had a very limited impact on
the level of individual doses. The potential of decontamination and its limitations were discussed withthe citizens in Date City, leading to ideas such as “No excessive decontamination is necessary” and “We
are creating our area for ourselves!” Therefore, Date city authorities and citizens came to the position
that further soil removal should be reconsidered.
The IAEA team is of the opinion that experience accumulated by the municipalities regarding theengagement with the communities and interaction with the national government is of high relevance toillustrate practical aspects of stakeholder-related issues in a mass scale remediation effort after a major
nuclear accident.
The IAEA team believes that the remediation efforts implemented in Date City, in particular, the early
initiation of the decontamination of the school yards and houses are worth being highlighted. In thisrespect, the IAEA team notes that the Mayor’s leadership and support from members of the public were
the important factors that together contributed to the expedient implementation of protective andremedial actions. There were some key aspects of the remediation programme in Date City, such as:
an objective to return to normal life as soon as possible being shared among the Mayer,
municipal government and the citizens;the active role of the Decontamination Promotion Centres;
the direct involvement of trusted and recognized experts, andthe availability of financial resources within the local budget (and confidence that expenses
could be charged to TEPCO at a later stage).
It was also reported by the official of Date City that the municipality faced various challenges toimplement the remediation works, including the lack of proper national remediation policy and response
framework; the influence of sometimes contradicting information in mass media; and the lack ofpractical experience in remediation and management of large volumes of the residual radioactive
material.
The IAEA team believes that this would be the right time to start a process to review the national
policy on environmental remediation (Act of Special Measures) in a way to provide alignment with
the IAEA GSR Part 3, specifically by addressing the requirements contained in the chapter relatedwith “Existing Exposure Situations”. In this regard, the accumulated national experience should
also be captured in reviewing the Act of Special Measures. The IAEA team also advises that due
consideration be given to enhance the dialogue/interaction among the national government,
Fukushima prefecture and municipalities concerned.

The effects of remediation in different areas (residential, farmland, forests and roads) were assessed by
the MOE. Based on a large data set, it was shown that the average reduction in air dose rates in the SDA(excluding forest areas) was in the range between 40 – 60%. In forest areas this decrease was lesseffective being around 23%. It was also revealed that the remediation activities in the SDA generated
approximately 8.4 x 106 m3 of contaminated soil and waste. From this amount approximately 1.0 x 106
m3 have already been transported from the temporary storage sites (TSS’s) to the ISF and incineration4

facilities5. In relation to the ICSA, the volume of contaminated soil and waste generated was 7.2 x 106
m3 out of which 1.1 x 106 m3 has been transported from the TSS’s to the ISF and incineration facilities6.
The IAEA team learned that the MOE would continue to manage the removed soil and to monitor theeffects of remediation, and, whenever necessary, implement supplementary remediation and measures
for reducing radiation doses in forests.
The IAEA team notes that the results presented on the remediation effectiveness consisted ofdiagrams showing an overall summary of the remediation efforts. The IAEA team considers that it
would be more useful if the data of different cities (under different circumstances) could be presented,
so that a better understanding of the variability in the effectiveness of the work done could be
captured and subsequently analysed.
The IAEA team views that, at the moment, the classification of the amounts of soil according to theactivity concertation intervals is based on information about where the soils came from and not on
individual determinations of the activity concentration of the materials contained in each bag. The
only measurement available for the bags is the exposure rate at the surface of each one of them. With
that in mind, it is advisable to consider the adequateness of establishing straightforward proceduresfor sampling and analysing soils in the bags. By doing so, classification of quantities of contaminatedsoil per activity concentration intervals could be obtained. Provided that criteria dictating themanagement of soils are based on the activity concentrations this procedure could facilitate decisions
on the best way to subsequently manage the soils contained in the bags.

It was also reported by Japanese experts that reduction in ambient dose rates did not necessarily lead toproportional reductions in individual doses, due to variability in the living habits of citizens in theaffected areas and the spatial distribution of the contamination. It was also presented that the use of
personal dosimeters has been recommended for more precise assessment of individual exposure.
The IAEA team emphasises the need to consider individual doses, as measured with personal
dosimeters, to support remediation decisions. An optimized monitoring programme to follow-up the
behaviour of the affected media (soil, vegetation, etc.) could be put in place. The possibility that theMOE publish/make available information on the amount of waste produced by various
decontamination techniques was suggested by the IAEA team. This information will be very relevantin the planning of remediation works in the event of another unlikely wide scale accident.

The IAEA team learned from the experience of an “Investigation Committee” that was created by
Tomioka Town to examine and verify the results of remediation works carried out by the MOE in thatmunicipality in the SDA. It was shown that, while verifying and confirming the results of full scaledecontamination carried out by the MOE, the Committee identified specific locations having higher air
dose rates for subsequent follow-up decontamination. The Japanese expert explained that it would be
expected that, upon return, the evacuees would likely resume their normal activities, including farming
and the consumption of locally produced food items.

5

As for January 20176

As for January 2017

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The IAEA team advises that a comprehensive health monitoring programme should be prepared tosupport the returning evacuees. Monitoring with whole body counters can also be proposed to assess
the level of internal exposure.

The development of the ISF was presented as a key element in the overall waste management strategy.
It was estimated by the MOE that the total area of the facility will occupy approximately 1,600 ha. From
this, total 79% is private land and 21% is national and municipal land. The MOE explained thatnegotiations with landowners have been being carried out on a case-by-case basis, and thatapproximately 376 ha have been already contracted as of the end of March 2017.
It was explained that different strategies were being pursued by the MOE to manage the accumulationof soils. According to the MOE, one of them is the recycling/reuse of the contaminated soil to be usedas part of base structure materials of coastal levees, seaside protection forests, freeway roads or covermaterials for waste disposal sites which will not be artificially changed for a long time. A demonstration
facility is being developed in the city of Minami-Soma (visited by the IAEA team)7. In this pilot testing,soils with activity concentrations below 3,000 Bq/kg will be tested for the use of embankment
construction material. A pilot recycling plant has been set up where contaminated soil bags from a TSS
will be first subjected to preliminary treatment, screening for caesium concentration, and quality control.
After construction the test embankment and surrounding environment will be monitored for a certain
period of time to evaluate the effectiveness of this approach. A water treatment plant has also been
constructed at the site to treat any contaminated water resulting from seepage through the embankment.
The plans are set in such a way that the dose to workers shall not exceed 1 mSv per year (during theconstruction or repair activities) and the dose to members of the public shall not exceed 0.01 mSv per
year when the constructions are concluded. The IAEA team believes that the demonstration project will
facilitate a better understanding and communication with citizens.
It is recognized by the MOE that effective engagement with the stakeholders will be needed to put theseplans forward. In this regard, “study sessions” on the theme of the demonstration project have been
carried out by the National Institute of Technology, Fukushima College, in cooperation with the MOE,
in such a way that views and concerns of the students are being identified.
Down blending of more contaminated soils with less contaminated ones was suggested by the IAEA
team as a procedure to be carefully considered, taking all safety considerations into account. Mixing
and blending of residual materials with other materials of similar characteristics, (e.g. as part ofconstruction materials for dams, roadbeds, or waste disposal cells on the footprint of the remediation
site; during ploughing of soil), may occur during remediation. Such an approach could be consideredwhen and where there is a need or convenience for enabling residual materials to be safely recycled orreused.
Volume reduction of combustible waste from decontamination is being addressed by incineration. A
dedicated rotary kiln type incineration facility (visited by the IAEA team) has been constructed in Date7

The adoption of this approach has indeed been recommended during the 1st IAEA Mission to Japan. In the Mission
report it was formulated (Advice #5) that: “…The Team encourages the relevant authorities to revisit the issue ofestablishing realistic and credible limits (clearance levels) regarding associated exposures. Residues that satisfy theclearance level can be used in various ways, such as the construction of structures, reclamations, banks and roads. The
IAEA is ready to support Japan in considering revised, new and appropriate criteria”.
(https://www.iaea.org/sites/default/files/preliminaryfindings2011.pdf)

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City. The facility has a processing capacity of 130 ton per day and will process 154,000 ton of thesewastes until 2020 when the facility will be decommissioned8. The ashes (bottom and fly) resulting fromincineration — approximately 200 kg for every 1000 kg of waste feed — are being stored at the site insuper bags and will be transported to the ISF. Typical values of the ambient dose equivalent rates at thesurface of the bags are 2.0 and 6.0 µSv per hour for the bottom and fly ashes, respectively. Apart fromvolume reduction, incineration helps eliminate the upsetting odour that results from the decompositionof the organic matter in such waste upon prolonged storage. It was reported that 30,000 ton of thesewastes will remain untreated due to the negotiated deadline to decommission the plant.
As the MOE moves ahead in implementing waste management activities and construction of facilities(e.g. ISF, treatment plants, etc.), the IAEA team advises that the MOE consider conducting safetyassessment of these activities and facilities and have it evaluated by an independent agency. This
would be in line with the advice provided in the report of the remediation mission in 20139.

In all actions implemented by the MOE, the stakeholder engagements were an essential part of theremediation process. Many of the decisions have been driven by the stakeholders, especially in the
ICSA area where the municipalities were in charge of remediation. Some of the adopted decisions arebeing reconsidered by the stakeholders in terms of their appropriateness
The IAEA team notes that it would be helpful for the MOE to assess the overall practices of
stakeholder engagement in the decision-making process and extract important lessons learned. If
considered appropriate, reorient future practices accordingly, especially during the repopulation of
the evacuated areas and continuous remediation to reach the long term clean-up goal.

Conclusions
The IAEA team joining the 3rd IAEA-MOE Experts Meeting reinforces the view that this type of
dialogue is extremely useful as it allows the exchange of experience/information, gaining insight on the
progress being made with the remediation of off-site areas affected by the accident and identifying thechallenges to be overcome. To the extent possible, the IAEA team provides considerations/suggestions
that can be appreciated by Japanese authorities in order to address such challenges. Consideration of
specific approaches of the Japanese authorities by the international community may also be beneficial
to have a wide range of stakeholders reassured that the activities being implemented conform to goodinternational practices or make sense from the technical/scientific point of view.
Once again, it is evident that progress is continuously being made with the remediation activities inJapan, and a milestone for completing the planned decontamination has been met on the timescales
originally foreseen. Major challenges remain in the future management of the decontamination wastes
and soils. Pursuing recycling options with proper safety assessments should not only be acknowledged

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The plan, which has been negotiated with local stakeholders, includes the complete removal of the facility from thesite.
9“The Mission Team encourages the responsible organization(s) to carry out appropriate demonstrations of the safetyof the facilities and activities for the management of contaminated materials, in particular for long-term activities, andto allow for their independent evaluation”. (https://www.iaea.org/sites/default/files/final_report230114.pdf)

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but encouraged. There is a definite requirement for extensive stakeholder engagement to assist inunderstanding the rationale behind each option, and to clarify, in a transparent manner, all the potential
controversial points so that a consensus can be reached on optimized/sustainable management options.
Upon a request, the IAEA can provide support to Japan in this effort.
In addition to the points indicated in the main body of this report — that can be seen as activities to beconsidered by the MOE for further implementation — in this concluding section it could be highlighted
that there is the need to capture the whole discussions held during the IAEA-MOE meetings (eventually
expanding each topic as to capture the inputs of a broader number of experts in a dedicated report to be
developed by the IAEA to share the lessons learned by Japan with the international community in amore comprehensive manner).

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