Research Conference on Post-accident Waste
Management Safety (RCWM2016)

November 7, 2016
Iwaki Business Innovation Center “LATOV” 6F(Iwaki-city, Fukushima)

Organized by
Collaborative Laboratories for Advanced
Decommissioning Science(CLADS)
Japan Atomic Energy Agency (JAEA)

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Research Conference on Post-accident Waste
Management Safety (RCWM2016)
Greeting
Thank you for your participation in the “Research Conference
on Post-accident Waste Management Safety (RCWM2016)”.
The purpose of this conference is to provide the place andoccasion to share the experiences in safe handling andmanagement of radioactive waste in order to promote theresearch activities in Japan.
PurposeTo accomplish the decommissioning of the Fukushima Daiichi
Nuclear Power Station (NPS), we need to gather theknowledge of domestic and foreign experts, and share
understanding of the present needs and future issues. It isalso necessary to strengthen R&D activities in the waste
management field.
Collaborative Laboratories for Advanced Decommissioning
Science (CLADS) is responsible to promote international
cooperation in the R&D activities on the decommissioning ofFukushima Daiichi NPS and to develop the necessary humanresources.
In this conference we hope that international experts sharethe information on the present state of Fukushima Daiichi
wastes and the wider experiences in the waste management.
Toru Ogawa
Director General of CLADS

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Program
12:00-

Registration

13:00-13:05

Opening Remarks

13:05-13:35“Management of Solid Waste Arising from Fukushima
Daiichi Decontamination and Decommissioning”
Mr. T.Kobayashi (TEPCO HD)

13:35-13:55“Activities of CLADS Waste Management Division”
T.Ashida (CLADS)

T.Ogawa (CLADS)

13:55-15:25 Session 1 Experiences of waste management in countries
Facilitator: K.Kostelnik (CLADS)
 Legacy Waste Management in the United States
Mr. R.SeitzSRNL Waste Management for Decommissioning in the UK
Dr. R.Orr (NNL) Plan and Implementation of Nuclear Waste Management in
FinlandDr. K.Rasilainen (VTT)
15:25-15:40

Coffee break

15:40-17:10

Session 2 Research activities of universities
Facilitator: Prof. S.Suzuki (U.Tokyo)
 Recovery and Volume-reduction Solidification of Radioactive
Elements from Solid Waste
Prof. K.Takeshita (Tokyo Inst. Tech) Rapid Analysis of Sr-90
Assoc. Prof. Y.Takagai (Fukushima U.)
 Activity of National Institute of Technology, Fukushima College
Assoc. Prof. S.Suzuki (NIT Fukushima C.)

17:10-18:00

Poster presentation

18:30-

Reception (LATOV 3F La•Pa•Pa)

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Abstract4

RCWM2016
Management of Solid Waste Arising from Fukushima Daiichi
Decontamination and Decommissioning
Tatsuro Kobayashi 1
1 Tokyo Electric Power Company Holdings, Inc.; kobayashi.tatsuro@tepco.co.jp

1. Waste Arising from 1F Decontamination and Decommissioning
Not only large amount but also many kinds of radioactive wastes (gaseous, liquid and solid
wastes) are generated by decontamination and decommissioning works in Fukushima Daiichi(1F), different from decommissioning at ordinary nuclear power stations. Most radioactivity
has been concentrated in the solid wastes to be safely stored in 1F site and prevent release anddissemination of radioactivity to the environment.
2. Waste Flow from Waste Generation to Storage
These solid wastes have been temporarily stored in the tentative storage areas. Then, they aretransferred to the storage buildings step by step and stored there until waste processing anddisposal phase. However, because of the limitation of the capacity of the storage buildings, thewastes should be volume-reduced as much as possible and more stabilized to be able to put
them into the storage buildings.
3. Current Status of Tentative Storage
At present, approximately 300,000m3 of rubble, etc.(rubble, felled tree, and used radioactive
protective equipment) stored in 1F site are categorized as follows: (1) Rubble (contaminatedmetal, concrete, and miscellaneous combustible materials, etc.) stored in tentative storage
areas, such as outdoor, sheet covered, container, or soil covered storage, etc. depending on theirsurface dose rate, (2) Felled trees (trunks, roots, leaves and branches) stored in outdoor
accumulation or underground storage pools to reduce fire risks, and (3) Used radioactive
protective equipment (coveralls, masks, shoes, and gloves, etc.) stored in outdoor container
prior to incineration. In terms of the secondary wastes arising from contaminated water
treatment, (4) Used absorbent towers stored in racks or box culverts depending on required
shield, and (5) Sludge and concentrated liquid stored in the existing buildings or tanks.
4. Future Challenge
The volume of rubble, etc. is estimated to reach 750,000m3 in 2028, which will exceed tentative
storage capacity. Therefore, reuse and recycling process of low contaminated concrete andmetals should be established to reduce the volume. In addition, the estimation of the waste
volume should be precise as much as possible applying for knowledge and experiences obtainedsince the accident. Then volume reduction facilities and additional storage buildings will be
designed and installed in a planned manner according to the volume estimation. Finally,tentative storage areas will be released step by step after newly installed storage buildings
begin operation.
In terms of the secondary wastes generated in the process of contaminated water treatment
system, the large size waste storage building will be constructed to accommodate the wastes
from present racks and box culverts. However, because potential risk of leakage still remain,
application of dehydration technology is under development using mock-up equipment by theInternational Research Institute for Nuclear Decommissioning (IRID) in order to stabilize theslurry wastes arising from multi nuclide removal facility (ALPS).
In addition, characterizing the wastes are indispensable for waste processing and disposal in
future, so the new research laboratories will be constructed adjacent to 1F site by the JAEA.

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Activities of CLADS Waste Management Division
Takashi Ashida 1
1 Japan Atomic Energy Agency; ashida.takashi21@jaea.go.jp

Introduction of CLADSCollaborative Laboratories for Advanced Decommissioning Science (CLADS) of JAEA wasestablished in 2015 to promote research and development towards the decommissioning of the
Fukushima Daiichi Nuclear Power Station (1F). To achieve this mission, CLADS consists of four
divisions.
(1) Waste Management Division(2) Fuel Debris Handling and Analysis Division(3) Severe Accident Propagation Behavior Evaluation Division(4) Remote System and Sensing Technology Division
Main efforts of the CLADS are as follows;(1) Establishment of a platform to rally the wisdom of experts from around the world(2) Enhancement of in and outside Japan research on decommissioning(3) Enhancement of human resource development in mid-and-long term(4) Establishment of an information dissemination function
Additionally, as an international research and development base, “International Collaborative
Research Building” has being constructing near the 1F as a core of the CLADS.
Research and Development of Waste Management
The accident at the 1F and restoration works have produced significant volume of various waste.
The characteristics of the 1F accident waste are very different from usual waste generated fromordinal nuclear power stations. The research and development works such as characterizationof the waste, investigation on safe storage, processing and disposal of the waste are carried out
based on the “Mid-and-Long-Term Roadmap”[1]. The contents of R&D activities of CLADS Waste
Management Division are as follows.
(1) Characterization
Analysis of various wastes
Evaluation of the amount and composition of radioactivity
Collection of physical/chemical data
Development of analysis method(2) Storage
Soundness of stainless vessel used for cesium adsorption apparatus
Safety technology for storing nuclear accident-derived wastes(3) Processing
Technology survey
Fundamental test of solidification
Technology selection(4) DisposalUnderstanding of the existing disposal concepts
Examination of disposal concept of accident-derived wastes
Examination of new disposal concept
These results are integrated to the basic concept of processing and disposal for solid radioactive
waste shown in the Roadmap.
References[1] Inter-Ministerial Council for Contaminated Water and Decommissioning Issues, Mid-andLong-Term Roadmap towards the Decommissioning of TEPCO’s Fukushima Daiichi Nuclear
Power Station, June 12, 2015.

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Legacy Waste Management in the United States
Roger Seitz
Savannah River National Laboratory; roger.seitz@srnl.doe.gov
Introduction
Remediation efforts result in large amounts of waste, which has resulted in the need for acomprehensive waste management strategy that includes multiple treatment, storage anddisposal options. The options involve considerations for waste acceptance criteria (WAC) andappropriate characterization and a variety of waste forms, containers, transportation options,as well as regulatory approaches that allow for public input. Dedicated on-site disposal cells
have been developed at multiple United States Department of Energy (USDOE) facilities andnew disposal capacity is being developed at commercial low-level waste (LLW) disposal
facilities (see Fig. 1). Facilities designed for disposal of hazardous wastes are also being used for
disposal of low activity radioactive waste resulting from remediation efforts. A number of
USDOE and commercial facilities are designed consistent with requirements for disposal ofhazardous wastes, and thus, are acceptable for disposal of mixed wastes comprising radioactive
and non-radioactive hazards. These facilities have a range of different disposal capacities up to
more than 15 million tons of waste.

Fig. 1: Facilities with liners and leachate collection systems used for disposal of remediation wastes at the USDOE Hanford (left) andIdaho (right) sites, respectively. The Idaho facility has been used for disposal of reactor vessels from decommissioned test facilities
on site as well as a variety of other remediation wastes. (Courtesy: USDOE)

Regulatory Approach
Decision-making for remediation and disposal of mixed waste is conducted through a UnitedStates Environmental Protection Agency (USEPA) regulatory process involving a rigorous
approach for evaluation of alternatives. The approach is conducted with requirements for
public involvement, including external regulatory oversight. The generally applied approach
involves nine criteria in a structured framework for decision-making (see Table 1). This
process has proven to be very effective in evaluating options and communicating the benefits ofthe selected alternatives, including on-site disposal cells at the major sites. The USEPA has anumber of prescriptive requirements (e.g., disposal facility design, waste treatment) that canhave advantages for consistency and public acceptance, but can also pose challenges for unique
site-specific wastes. The prescriptive design for disposal facilities has been very successful for
public acceptance. However, the prescriptive approach for waste treatment can lead tosituations where the standard treatment may not be optimal for a specific waste and it isnecessary to justify a different approach. When it is necessary to model the performance ofsome waste forms for a performance assessment, there is a need to develop parameters to
support the modeling effort. This has been a challenge, because the detailed data for a
performance assessment are not typically collected to support disposal of hazardous wastes.

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Table 1: Based on nine criteria used for decision-making.

Regulatory
1. Protection of Human Health
2. Compliance with Federal and State Regulations
Optimization
3. Long-term effectiveness (e.g., WAC and safety assessment)
4. Reduction of toxicity, mobility or volume of contaminants (e.g., treatment, containers)
5. Short-term effectiveness (e.g., worker protection, transportation)
6. Implementability at the site (e.g., WAC)
7. Cost effectivenessStakeholders
8. Regulatory acceptance9. Community acceptance
Addressing Challenging Wastes
Remediation has resulted in the generation of a wide variety of wastes that have required astrategic approach to manage. The vast majority of the wastes are routine and relatively
straightforward, although disposal capacity is needed (e.g., soils, lightly contaminated debris).
However, a variety of specific, more challenging wastes are also produced (e.g., reactor
components, ion exchange resins, etc.). These more unique wastes lead to challenges for
identification of appropriate treatment and disposal options and also may test the standard
regulatory approaches. Solid secondary wastes like ion exchange resins illustrate a variety ofstrategic challenges associated with remediation wastes in the United States. The presentation
includes some practical handling and treatment challenges as well as challenges to identify
inputs and assumptions required to model the waste forms.
For efficient identification of research priorities, it is critical to integrate the performanceassessment activities with the research teams that conduct research to support the analyses.
Initial performance assessment modeling is used to identify assumptions and parameters thatare important for the conclusions of the analysis. The researchers and performance assessment
modelers work together to identify key areas of need. This provides a benefit for the efficiencyof the process (i.e., research is focused on the significant needs) and it also helps the researchers
provide justification for the testing and characterization work that they will be conducting.
Summary
When considering alternatives for treatment, storage and disposal, there are a number offactors that are addressed in the national strategy. It is a combination of regulatory andtechnical challenges. The regulatory challenges include: balancing prescriptive and performancebased approaches, establishing WAC for treatment and disposal facilities, implementing
decision approaches capable of considering multiple criteria, and allowing for a transparent
approach with public involvement. Technical challenges will typically focus on the mostchallenging, unique wastes. The technical efforts must consider WAC for treatment, storage anddisposal facilities; transportation requirements; requirements for waste form and containers.
The regulatory and technical considerations should be linked to the overall plan for remediation
to help identify critical assumptions that may impact the options for final disposal of waste.
Given the large amounts of input and assumptions for modeling, it is important to integrate datacollection and modeling efforts to help prioritize efforts on the data and assumptions that are
most significant for the decision to be made.

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Waste Management for Decommissioning in the UK
Robin Orr
UK National Nuclear Laboratory; robin.orr@nnl.co.uk
The United Kingdom was one of the first countries to adopt nuclear energy as a source of civil
electricity production. Indeed, the UK Calder Hall nuclear reactors were, in 1956, the world’s
first to generate electricity on an industrial scale. Ultimately 26 Magnox reactor units (nowclosed), 14 Advanced Gas Reactor (AGR) units and one Pressurized Water Reactor (PWR) werebuilt in the UK. To support the development and operation of the UK nuclear power station fleet,research/prototype reactors and research facilities were built as well as plants for enrichmentof uranium, fuel fabrication, spent fuel storage and spent fuel reprocessing.
Several research/prototype reactors and other plants have already been successfully
decommissioned in the UK but many nuclear facilities remain. The Sellafield site is the largest
nuclear site in the UK and represents its largest decommissioning challenge. It is expected that
decommissioning and site restoration will continue beyond the year 2100 [1]. Decommissioning
the facilities will generate a range of wastes, the majority of which will be classed as Low Level
Waste (LLW), destined for near-surface disposal [2]. However, particular challenges duringdecommissioning arise from the retrieval and management of Intermediate Level Wastes (ILW)
and nuclear materials currently stored in legacy facilities.
In the early 1980s the UK initiated a programme to develop treatment processes for solid andslurry ILW from spent fuel reprocessing. A phased development approach was established, fromlaboratory scale experiments to commissioned plant operation. From this work, four waste
cementation plants were built at Sellafield to process operational arisings from reprocessing.
These plants have now been operating for over 25 years and produced more than 50,000 waste
packages. Considerable experience has been established in the UK on the cementation of wastes,development of criteria for disposability [3] and the demonstration of wasteform performance.
This experience has been built on to manage decommissioning wastes.
The highest priority tasks at Sellafield are decommissioning the high-hazard legacy plants from
historic fuel reprocessing operations that currently store higher activity wastes and materials[1]. Unlike feeds to current waste plants at Sellafield, the ILW from the legacy plants will be aheterogeneous mix of materials, exhibiting a range of hazards, and will vary over the waste
retrieval period. In addition, there are significant practical constraints on the engineering thatcan be implemented to mitigate the hazards from these wastes. These challenges require a more
flexible and pragmatic approach than in previous waste treatment processes.
This presentation will provide a brief overview of the UK framework for the management ofradioactive wastes. Experience gained from the development of waste treatment and cement
immobilization of reprocessing wastes will be summarized before discussing the different
challenges posed by ILW retrieved from UK legacy facilities during decommissioning. Examples
of strategies for wastes at the UK Sellafield site and associated research will be discussed.
References[1] Nuclear Decommissioning Authority, Strategy Effective from April 2016.
[2] Nuclear Decommissioning Authority, Radioactive Wastes in the UK: A summary of the 2013
Inventory.
[3] Geological Disposal Generic Waste Package Specification, Radioactive Waste Management
Limited.

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Plan and Implementation of Nuclear Waste Management in Finland
Kari Rasilainen
VTT Technical Research Centre of Finland Ltd; kari.rasilainen@vtt.fi
Introduction
Finnish nuclear waste management programme is today globally the most advanced one vis a
vis low and intermediate level waste and spent nuclear fuel management. The plans andschedules developed over 30 years ago are implemented today with only minor modifications.
The features of Finnish success story cover e.g. coupling scientific research, decision making,regulatory needs, and implementor needs in the programme. The well-tested practices in siting
a nuclear waste repository, and related site investigations, may be of interest in other countries
as well, although one cannot directly transfer methods or approaches from country to country.
The characteristic Finnish approach has been to step wise go deeper and deeper into site
investigation and disposal concept development using subsequent safety assessments asmeasure of understanding.
Low and intermediate level waste management
Currently there are two operating licensed low and intermediate level waste repositories inFinland, located at the operating NPP sites Loviisa and Olkiluoto. They are geologic repositories
at the depth of around 100 m in crystalline bedrock. There are well-developed plans to extend
the repositories in order to dispose of future decommissioning wastes of the respective NPPs.
High level spent nuclear fuel management
Finland will probably be the first country to license a deep geological repository for spent
nuclear fuel. The repository will most likely be based on the KBS-3V concept, with V standingfor vertical, meaning that individual disposal canisters containing the spent fuel bundles will bedisposed of in individual vertical deposition holes, one canister per hole. The systematic
programme for spent fuel disposal has so far lasted over 30 years, see Fig. 1.

Fig. 1. Timeline of spent fuel disposal in Finland [1].

Costs of nuclear waste management
The total costs of all nuclear waste management arising from reactors currently running or
under construction was estimated to be 6,5 B€ in 2012, with spent fuel management covering

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for 3,5 B€. This estimate covers the management of operating waste, spent fuel, anddecommissioning waste. Cost estimate for the future management of currently existing (end of2015) nuclear waste is around 2,45 B€ (no discounting). The money for nuclear waste
management is collected from nuclear waste producers into the State Nuclear Waste
Management Fund with the idea that at all times there is enough money to manage the currently
existing nuclear waste even if the nuclear waste producers would go bankrupt.
References[1] Posiva, 2013. Safety Case for the Disposal of Spent Nuclear Fuel at Olkiluoto - Models andData for the Repository System 2012, Report Posiva 2013-01, p. 49.

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Recovery and Volume-reduction Solidification of Radioactive
Elements from Solid Waste
Kenji Takeshita
Advanced Nuclear Fuel Cycle Unit, Institute of Innovative Research, Tokyo Institute of Technology;
takeshita.k.ab@m.titech.ac.jp
Large amounts of radioactive nuclides were released to the environment by the hydrogen
explosion of the buildings of 1F NPP during March 11 to 15, 2011 and forest and farmland were
contaminated by the fallout of radioactive elements. Then, large amounts of solid wastes suchas soil, tree and rubble were generated. Their generation amounts in the 1F NPP site were about
82500 m3 for cut tree and 155100 m3 for soil and rubble. Since these wastes cause the exposureof workers to radiation, the radioactive elements has to be recovered from these wastes,
concentrated and immobilized in stable materials. The decontaminated solid wastes are reused for pavement materials, construction materials etc. As a result, the working environment
in 1F NPP site will be improved and the nuclear decommissioning of 1F NPP will be promoted
greatly. A part of the contaminated soil is stored with rubble, but the recovery of soil does notprogress enough. The results of radiation measurement carried out by JAEA in March, 2015
suggest that high 137Cs radiation of ten
thousands to millions Bq/kg was observed in
the soil near the reactor buildings. Those of
90Sr in the sampled soils were low values in
the range of 300 to 1500 Bq/kg [1]. According
to the progress of the decommissioning of 1F
NPP, treatment techniques of contaminatedsoil will be required. Especially, Cs and Sr areadsorbed strongly into 2:1type layered clay
minerals,suchasvermiculateandmontmorillonite. The development of highdecontamination technology is indispensablefor the desorption of radioactive elements andthe reuse of decontaminated soil.
Based on recognition of such current status,
an integrated system for the recovery,
concentration
andimmobilizationofradioactive elements from environmental
waste materials such as soil and tree isdeveloped in this study. However, we have noexperience on the treatment of large amountsof environmental wastes. In the current stage,
most of radioactive elements (Cs and Sr) incontaminated soil is transferred to 2:1 typelayered clay minerals such as vermiculate and montmorillonite and adsorbed strongly into
them. Especially, the adsorption of Cs is very strong. Under these circumstances, we develop a
new integrated system for the recovery, concentration and immobilization of radioactive
elements in the contaminated soil. For the cut tree, the same system will be developed inparallel with the fundamental research on the chemical characteristics of radioactive elements
in ash obtained by the combustion of cut tree and the adsorption of them into the ash. This isbecause the chemical conditions of radioactive elements in the ash are unknown and thefundamental knowledge is needed for the development of suitable system. Then, a newtechnique to remove Cs from the contaminated soil and highly volume-reduced waste is12

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required for the economical and safe disposal. In this study, we introduce a new recovery andvolume-reduction solidification process of these solid wastes.
Firstly we studied the removal process of Cs from contaminated soil, which consists of sievingof contaminated soil, hydrothermal decomposition of clay minerals, adsorption of Cs in ferric
ferrocyanide, thermal decomposition of ferric ferrocyanide adsorbing Cs, leaching of Cs fromthe residue with water and vitrification of Cs, shown in Fig.1, Clay minerals that adsorbs
strongly Cs was separated by the sieving of contaminated soil. Secondary Cs in clay minerals
was recovered to water by a hydrothermal decomposition method with plant biomass under
the conditions of 180-250ºC and 1.0-4.0 MPa [2]. Cellulose and hemicellulose in the plantbiomass were decomposed to some organic acids and these organic acids in the subcriticalwater dissolved clay minerals, especially vermiculite which adsorbs Cs very strongly. More than
95% of Cs in vermiculite was released in hydrothermal water by a repetition of hydrothermal
operation and concentrated by a typical Cs adsorbent, ferric ferrocyanide (Prussian Blue),
which was decomposed in air at 300ºC [3]. Cs in the residue was recovered easily by pure water.
Finally Cs was solidified and further concentrated in borosilicate glass. Mass and radioactivebalances of the proposed process were estimated from the results of fundamental experiments.
The volume of vitrified waste is reduced to about 1/20000 of that of contaminated soil [4].
These results suggest that both the removal of Cs from contaminated soil and the high volumereduction of Cs waste can be attained by the introduction of the proposed process.
References[1] TEPCO Homepage, www.tepco.co.jp/nu/fukushima-np/.../t120730_02-j.pdf[2] I.Takatsuka, H.Takahashi, T.Fukuda, M.Harigai, Y.Inaba and K.Takeshita, “Fundamental
Study on Cs Elution Technique from Vermiculite by Hydrothermal Treatment Using
Cellulose-based Biomass (in Japanese)”, Journal of the Society for Remediation ofRadioactive Contamination in the Environment, 4(3), 231 – 238 (2016)[3] J. Munezawa, N.Ito, R.Ogata, S.Inoue, Y.Inabaand M.Harigai, “Development of Cesium
Recovery System for High Efficiency and Volume Reduction- Behavior of Cesium salt in
Combustion Treatment of Prussian Blue – (in Japanese)“, Journal of the Society for
Remediation of Radioactive Contamination in the Environment, 4(1), 35-44 (2016)[4] K. Takeshita, “Removal Process of Radioactive Cesium from Soil contaminated by
Fukushima Daiichi Nuclear Accident”, Atalante 2016, Keynote Lecture (Paper No.169), Le
Corum, Montpellier, France (2016)

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Rapid Analysis of Sr-90
Yoshitaka Takagai1
Makoto Furukawa 2
Yutaka Kameo 3
Katz Suzuki 4
1 Fukushima University; takagai@sss.fukushima-u.ac.jp
2 PerkinElmer Japan Co., Ltd.; Makoto.Furukawa@PERKINELMER.COM
3 Japan Atomic Energy Agency; kameo.yutaka@jaea.go.jp
4 Japan Agency for Marine-Earth Science and Technology; katz@jamstec.go.jp

Radioactive strontium-90 scattered by nuclear power plant accident was specificallyquantified by conventional inductively coupled plasma quadrupole mass-spectrometry(ICP-QMS) preceded by on-line chelate column separation (based on lab-on-valve) andoxygen reaction (designated the cascade step). The proposed system overcomes theisobaric interference of 90Zr, whose soil concentration exceeds that of 90Sr by more thansix orders of magnitude. In addition, the system requires no ultimate mass
spectrometry or radioactive 90Sr standards. The radioactive 90Sr standard was replacedwith the stable isotope 88Sr as a pseudo-standard. The modified ICP-QMS system yieldeda precise, reproducible sharp 90Sr peak in the ICP-MS profile. The elution time of 90Sr
was highly reproducible (RSD = 0.5 %). After implementing the cascade-step, thedetection limit (DL) was 0.28 Bq/L (0.06 ppq) in 90Sr analysis and 2.9% of repeatability(10 ppq 90Sr(n = 10)) within approximately 20 min. Solid sample was able to be applied
after the treatment of microwave digestion system. The 90Sr from environmental
contaminated soil samples collected from areas at a distance of 10 and 20 km from the
Fukushima daiichi nuclear power plant ranged from 52 Bq/kg to 73 Bq/kg, with nostatistical difference between the proposed and general methods at 95% confidence
level. The analytical technique has overcome the analytical problems in radiometry andconventional ICP-MS by using chemical system. The proposed method offers an
attractive alternative use for ICP-other ionization mass spectrometry as an enrichment
or purification step, thereby expanding the scope of ICP-mass-spectrometric analysis.
References[1] Y. Takagai, M. Furukawa, Y. Kameo, and K. Suzuki, Anal. Methods, 6, 355 (2014).
[2] M. Furukawa and Y. Takagai, Anal. Chem., 88, 9397 (2016).

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Activity of National Institute of Technology, Fukushima College
Shigekazu Suzuki 1
Shiro Jitsukawa 1
Seichi Sato 1
Katsuhiro Aoyagi 1
1 National Institute of Technology, Fukushima College; ssuzuki@fukushima-nct.ac.jp

Introduction
 Decommissioning of Fukushima Daiichi nuclear power station is a national challenge. Midlevel engineer training from a medium- to long-term perspective on to proceed withdecommissioning is a pressing issue. A training of practical engineer is the theme of technicalcollege as institution of higher education of the National. In particular, National Institute ofTechnology, Fukushima College (NIT, Fukushima College) is located in the most close to the
Fukushima Daiichi nuclear power station in the higher education of the National. Therefore in
NIT, Fukushima College, a position to lead the national colleges across the country in the field of
decommissioning education has been required.
 Students of NIT Fukushima College have an interest in decommissioning technology. Somestudents choose nuclear power-related companies in place of employment. In order to meet themedium- and long-term theme of the region, incorporate the decommissioning basic research in
graduate research and special studies carried out human resource development throughresearch.
The establishment of decommissioning human resource development consortium
 NIT, Fukushima College had been submitted as a business representative on the public
offering of Education, Culture, Sports, Science and Technology Ministry. As a result, ourapplication has been adopted by the business for one year as a feasibility study. Application
title was "Human resources training on the decommissioning of nuclear power plant, based on
study for graduation --- interdisciplinary challenge from Fukushima".
 In the wake of this adoption, "Decommissioning human resource development consortium"
was established in 2015 March 17 by NIT, Fukushima College. In this council, the nationwide
technical colleges, universities and research institutions pursue together human resource
training in the medium- to long-term perspective. Place the Council of the Secretariat in the
Fukushima College, Takayuki Nakamura Fukushima College president was appointed firstchairman, and Tetsuji Choji Kagoshima college president was appointed vice chairman. 2016
April at 34 technical colleges, 9 universities, 3 local government relationship, 6 privatecompanies have joined.

Education program on
decommissioning This educational program is designed
to correspond with the "human resource
development and cooperation between
higher education and research institutes
in the medium-and-long term viewpoint"
which is related to a governmental
medium-and-long term roadmap for
TEPCO’s Fukushima Daiichi Nuclear
Power Plant. This education program isconstituted by three pillars; research andFig. 1 Three pillars of education program on
decommissioning

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development, education and the facilities available (Japan Atomic Energy Agency
Naraha Remote Technology Development Center).
 In 2015, classes on decommissioning have been offered in two subjects new. Classes
are "decommissioning and Society" of the 3-year target, a "decommissioning
engineering" of the 4-year target, any one credit, was carried out in the intensive course
format.
 In 2016, internship programs for decommissioning and the two new lectures havebeen started. At the same time, the Technical College has promoted the cooperation in
graduate research and special research. In 2017, by starting classes on
decommissioning in first grade and fifth grade, education program on decommissioning
will be completed. Internship is carried out complexly at two locations of companies
and city office. In the company learn the decommissioning technology. In the city officeunderstand the duties as a government on decommissioning.
Overview of Creative Robot Contest for Decommissioning In order to get interested in the decommissioning to the young generation believes
that education through the robot is effective. In addition, a variety of practices, such as
PBL education and active learning lesson can be seen in each technical college. This
Robocon also carried out by such PBL and active learning. It is the purpose to have aninterest in decommissioning to the student through the manufacturing of robot. At thesame time, it aims to cultivate the contributing to the "creativity education" "problemsolving ability" and "ability to identify challenges" students.
 Overview of the competition challenges are as follows.
1) Field
To select the playing field in each team from the two fields of the following assumes thereactor building.
a) Mock-up stairs   b) Standard step field
2) Field environmenta) Mock-up stairs and b) standard test field have a common environment for thefollowing.
a) It is no darkness lightingb) Not be able to face up to the body to operate the robot by remotec) Radio wave does not reach because there is a thick wall of concrete
3) Challenges of robota) Mock-up stairs- Carry the luggage of weight 5kg to the second floor from the first floor. And comeback to its original location by placing the luggage.
- Examine the thing that is put on the second floor. It should be noted that thelocation is undefined.
b) Standard step field- Examine the field of shape (such as area and irregularities).
- Check things that are located in the field. It should be noted that the location is
undefined.
 There were submitted from all over the country in the national and public technicalcolleges of the 13 colleges 15 team in this contest. Results of document screening, wasobserved participation of 15 teams.

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Abstract of Poster Presentation17

In situ X-ray Absorption Spectroscopy Study on Hydrogen
Recombination Reaction of Precious Metal Nanoparticles Catalysts
Yusaku Kimura 1, Daiju Matsumura2, Yasuo Nishihata2, Masashi Taniguchi3, Juichiro Mizuki1,
Hirohisa Tanaka1
1 Kwansei Gakuin University; asanisimasa@kwansei.ac.jp,
2 Japan Atomic Energy Agency,
3 Daihatsu Motor Co., Ltd.
Abstract
In case of severe accidents in nuclear power plants, and during long-term storage of radioactive
waste, hydrogen is generated. The research on hydrogen recombination into safe water by
precious metal nanoparticle catalyst has attracted attention. In this study, the mechanism of
catalyst poisoning of carbon monoxide has been investigated by in-situ time-resolved analysis
on the precious metal using Dispersive X-ray Absorption Fine Structure (DXAFS) at SPring-8. It
is found that formation of surface oxide plays an important role in the hydrogen recombination,
and CO inhibits the absorption and causes a decrease in activity. Furthermore, the use of ceriacomposite-oxides, having oxygen storage capacity, as the support was found to reduce CO
poisoning. It was possible to obtain useful guidance in catalyst design.

Application of Automotive Catalyst to Hydrogen Recombiner
K. Takenaka1, S. Kishimoto1, M. Taniguchi2, Y. Kamiji3, Y. Nishihata3, H.Tanaka1
1. Kwansei Gakuin University eoy10812@kwansei.ac.jp
2. Daihatsu Motor Co., Ltd.
3. Japan Atomic Energy Agency
Abstract
At the severe accident of the Fukushima Daiichi nuclear power plant, seawater has been
injected for cooling the reactor. When the nuclear waste should be kept isolated, water isdecomposed to generate hydrogen and oxygen by radiation in the container. So that highly
active recombiner catalyst is required. The intelligent automotive catalyst was found to haveexcellent activity to recombine hydrogen from a room temperature. In our laboratory, robust
catalyst materials have been developed for water vapor and the catalyst poison such as carbon
monoxide inhibits the hydrogen oxidation reaction. We are aiming at the realization of highly
active recombiner.





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Results of Preliminary Analyses on Natural Convection Behavior
of Hydrogen Gas Generated in a Radioactive
Long-Term Waste Storage Container
Yusei Tanaka 1, Yota Suzuki 1, Kazuyuki Takase 1
1 Nagaoka University of Technology; s165048@stn.nagaokaut.ac.jp
1 Nagaoka University of Technology; s165047@stn.nagaokaut.ac.jp
1 Nagaoka University of Technology; takase@vos.nagaokaut.ac.jp

Abstract

In the radioactive waste storage container, because the concentration of hydrogen gas
generated by the decomposition of water by radiation increases with time, it isimportant to accurately grasp the behavior of the hydrogen gas in the sealed container
for safety improvement of the storage container. Since the hydrogen gas is heated by theradioactive material accumulated in the storage container, it is conceivable that naturalconvection is formed. Therefore, in order to clarify quantitatively the natural convection
behavior of hydrogen gas due to the decay heat of radioactive materials in the long-term
waste storage container, preliminary analyses were performed on the system of a smallscale experimental apparatus in which specification of the long-term radioactive waste
storage container is simply simulated.From the present results, the perspective which
can predict natural convection phenomena in the long-term waste storage container
numerically was obtained.

A Plan of Basic Experiments for Performance Evaluation ofa Long-Term Radioactive Waste Storage Container
for Reducing Hydrogen Gas Concentration
Yota Suzuki 1, Yusei Tanaka 1, Kazuyuki Takase 1, Ryutaro Hino 2
1 Nagaoka University of Technology; s165047@stn.nagaokaut.ac.jp
1 Nagaoka University of Technology; s165048@stn.nagaokaut.ac.jp
1 Nagaoka University of Technology; takase@vos.nagaokaut.ac.jp
2 Japan Atomic Energy Agency; hino.ryutaro@jaea.go.jp

Abstract

In the decommissioning of nuclear power plants, the long-term management of radioactive
waste of fuel debris, etc. are necessary. In the process, hydrogen which is the flammable gas
is generated by the decomposition of water by radiation. Therefore, it is important to ensure
the safety of the waste storage container to reduce the concentration of hydrogen gas, and tokeep below the explosion limit (4%). Consequently, a basic experiment to investigate theeffectiveness of the waste storage container with the flammable gas concentration reduction
mechanism using the passive autocatalytic recombiner (PAR) has been planned. The present
study describes the research plan to use a small modeled experimental apparatus.

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Potential Applicability of Bioconsolidation for Retardation of
Diffusional and Convective Transfer of Effluent Radioactive Species- The technological Basis and Prospect for Actual Application Shigekazu Suzuki 1 and Kenichi Kurumada 1
1 National Institute of Technology, Fukushima College; kurumada@fukushima-nct.ac.jp

Abstract
Bioconsolidation by anaerobic metabolic activities of in-ground microbes was intended todensifying the soil for the purpose of mitigating the effluent aqueous radioactive species
accompanied by the transfer of in-ground environmental water. Similar biological process has
been found in the spontaneous formation of hard and rigid calcium carbonate scale on the innerwall of drainage pipes in landfill sites, which is sufficiently densified to prevent water frompermeating out. The artificial conditioning for the in-ground formation of calcite is expected tocontribute to reducing the effluent of radioactive substances from the decommission site. The
authors showed that feeding calcium ion and nutritious organic substances with water into theground can lead to the generation of microbe-derived calcite solid phase which forms denseinterconnections amongst the constituent soil particles. To enhance the crystal nucleation of thecalcite sub-micron particles, the nucleation-promotive effect of adding carbonyl-containing
resin into the soil is to be further investigated. The appropriate conditions for the continuousand short-term growth of the soil-bridging calcite phase need to be experimentally clarified in
the future investigation. In parallel with carrying out these fundamental laboratory experiments,
the authors seek for collaborative opportunities to implement more actual on-site examinations
with the help of advices by those who have superior and broader expertise on what are themore actual technical requirements for the mitigation technologies of the radioactive effluents.

Enhanced Desorption of Cs from Cs Collapsed Interlayer Region ofVermiculitized Biotite by Hydrothermal Treatment with Eluting Cations
Xiangbiao Yin 1, Hideharu Takahashi 1, Toshihiko Ohnuki 1, and Kenji Takeshita 1
1 Laboratory for Advanced Nuclear Energy, Tokyo Institute of Technology; yin.x.aa@m.titech.ac.jp
Abstract
Natural soil has ability of immobilizing radiocesium (Cs) within phyllosilicate fraction. The
objectives of present study are to clarify how Cs fixation on vermiculite is influenced bystructure change caused by Cs sorption at different loading levels and how Cs desorption isaffected by various replacing cations induced at different treating temperature. As a result,more than 80% of Cs was readily desorbed from vermiculite with loading amount of 2%
saturated Cs (5.49×10-3 mmol g-1) after four cycles of treatment of 0.01M Mg2+/Ca2+ at room
temperature, but less than 20% of Cs was desorbed from saturated vermiculite. These distinct
desorption patterns were attributed to inhibition of Cs desorption by interlayer collapse ofvermiculite, especially at high Cs loadings. In contrast, elevated temperature significantly
facilitated divalent cations to efficiently desorb Cs from collapsed regions. After five cycles oftreatment at 250 with 0.01M Mg2+, ~100% removal of saturated Cs was achieved. X-ray
diffraction analysis results suggested that Cs desorption was completed through enhanced
diffusion of Mg2+ cations into collapsed interlayer space under hydrothermal condition resulting
in subsequent interlayer decollapse and readily release of Cs+. The results were expected toprovide new insights to explore available decontamination technology for Fukushima Cscontaminated soils.

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A Study of the Economic Effects by the Nuclear Industry andDevelopment of Human Resources in Regional Economy
from the Point of the Younger Generation Consciousness Concerning
Nuclear Energy*Aika Fujiki1, Kazunori Akutagawa1
1 National Institute of Technology,Fukushima College; 10532@fsnct.com

Abstract
The restoration work from the nuclear accident in Fukushima would continue about 40 years.
Development of human resources engaged in the work is very important to conduct the longterm restoration. We surveyed opinions of the Japanese and French young generations’ attitude
toward nuclear energy after the accident. Opinions of about 100 students of National Institute ofTechnology in Japan were compared with those of French students.

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