Nuclear Damage Compensation and Decommissioning Facilitation Corporation

The International Forum on theDecommissioning of the Fukushima Daiichi NPS

Analysis Strategy for Promoting
Decommissioning
August 29, 2022

Kazuyuki KatoManaging Director
Nuclear Damage Compensation and Decommissioning Facilitation Corporation（NDF)
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Overview of contaminant sources of solid waste and waste characteristics

Dispersion and diffusion

Water treatment
deviceRubbles/ felled trees

RubbleFelledtrees

ContaminatedwaterSoilWaste, etc.
generated by fueldebris retrieval

Generated to date•••••

Large amount of material andwidely distributed.
Trees and soil have a limited
record of processing/disposal
Surface contamination bydispersion and diffusion mainly
Permeation contamination
through partially stagnant water
Expecting scaling with Cs•

Generate in thefuture••

Large amount and high-does ofmaterial (high-βγ, high-α)
Difficult to collect raw waste

Secondary waste generated
by water treatment
Secondary wasteby treatment ofcontaminatedwater

Replaced pipingand storage tanks

Generated to date•••

Limited record ofprocessing/disposalDifficult to collect raw waste
Some amount of generation andnuclides can be estimateddepending on the characteristicsof the device.

Contaminated by seawater from tsunami, boron contained in boric acid solution,and chemical substances such as anti-dispersion agents, etc.

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Points on waste management at 1F for smooth decommissioning

Time-consuming and laborious due to diverse and a large
physical volume of unconventional nuclide compositions.
➢ Volume reduction is important.
→ Introducing the waste hierarchy concept➢ Time-consuming to characterize→ Development of efficient analytical/evaluation methods➢ Time-consuming to classify waste (How do they fit into the conventional
categories? Or more reasonable to create a new classification?)→ Considering optimization methods with uncertainty in mind throughto disposal (without reworking)➢ Identifying which existing technologies can be applied to which waste andto what extent→ Consideration/improvement of the scope of application in various
processing technologies◆ It’s not as difficult as to be get stuck, but it’s taking long.
◆ It is necessary to revise the targets based on results as appropriate toaddress a large volume of waste in parallel with efforts to reduce the volume.
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Current Situation of Characterization
Reconnaissance survey
Start Characterization
analyze the sample which we were able to gather

Detailed characterization
Inventory Estimation for R&D✓ Integrated waste management strategy✓ Propose rational regulatory system early
We are here

Confirmation monitoring4

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Challenge of 1F Waste Characterization
After the accident (Start preliminary characterization)✓ Regardless of priority, we carried out analysis from the sample which wewere able to gather

No regulatory requirement
Integrated R&D for waste management✓ Establishment of waste management strategy for 1F waste is required
early (around FY2021) → Regulatory System✓ Estimation of total inventory is basis for study disposal concept,
processing technology and WAC etc.
✓ Some waste streams are difficult to sample✓ Considering the limit of storage area, HVLAW is a critical issue

Because of huge volume of waste, time for analysis may
be bottleneck of decommissioning5

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Key Issues in Characterization➢ Historical knowledge is lost
➢ Some waste streams are difficult to sample➢ Needs to estimate total inventory of waste➢ No regulatory requirement and WAC✓ What is the priority of measurements (dose rate, gamma
spectrometry, total alpha, concentration for each nuclide)?
✓ How to determine nuclides to be analyzed?
✓ How much analysis is enough?
✓ How to determine the priority of waste streams to be analyzed?

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Towards Efficient Characterization
How to accelerate the characterization on the condition that thenumber of data is limited➢ How to group waste streams✓
Make small numberwaste groups tocharacterization
lower the burden ofTowards
theofefficient
processing/disposal✓ In case of lack of analysis data
✓ New streams are expected to be generated by decommissioningactivities➢ How to use analytical modelling✓ Experiences (to what kind of waste?)✓ Statistical approach➢ No destructive analyses✓ Possible method, experience➢ Conservative evaluation against uncertainty✓ To avoid analysis, set enough conservatism is feasible?

To examine necessary analysis and evaluation with clear
objectives efficiently is important7

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Efficient Confirmation Monitoring
Especially for HVLAW, we will have options of clearance,
limited use in the site etc. for the waste minimization. In theconfirmation monitoring phase (regulatory phase),Efficientconfirmation
monitoring
efficiency
of characterizationis still importantto achievesmooth decommissioning because of high volume of waste.
➢ How to decrease the number of analysis✓ Using analytical modelling (experience)✓ Conservative evaluation of nuclide concentration✓ Statistical approach➢ Experience of applying efficient analyzing method✓ Simple and easy analyzing method✓ Automatic➢ What others?
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３．福島第一原子力発電所の廃炉に向けた技術戦略 3.1 燃料デブリ取り出し
３．福島第一原子力発電所の廃炉に向けた技術戦略 3.2 廃棄物対策

Major
targets
and progress for solid waste
燃料デブリ取り出しに係る主な目標と現状
廃棄物対策に係る主な目標と進捗
Major targets➢ In a processing/disposal effort, processing/disposal strategies forsolid waste and technical prospects on their safety should bemade clear by around FY 2021.

Progress

Providing processing/disposal strategies for solid
waste and technical prospects on their safety

a. Present how to proceed with volume reduction of solid wasteb. Develop analytical/evaluation methods for efficient characterizationc. Establish a method for rationally selecting safe
processing/disposal methods for solid waste once necessary
information including characterization is obtained
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３．福島第一原子力発電所の廃炉に向けた技術戦略

3.2 廃棄物対策

３．福島第一原子力発電所の廃炉に向けた技術戦略

3.2 廃棄物対策

Processing/disposal
strategies for solid waste and technical prospects on their safety
固体廃棄物の処理・処分方策とその安全性に関する技術的な見通し

固体廃棄物の処理・処分方策とその安全性に関する技術的な見通し

Fig. Development of methods to rationally select safe processing/disposal methods
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無断複製・転載禁止 原子力損害賠償・廃炉等支援機構©Nuclear Damage Compensation and Decommissioning Facilitation CorporationResult of major technology development : Characterization
1. Examining efficient analytical methods for characterization(mainly on hardware)
Simplify/accelerate analytical methods.
① The types of waste subject to characterization and nuclides tobe evaluated were selected.
② Technology development for automating and acceleratingcharacterization③ Development of high-radiation dose sampling technologies

2. Consideration of characterization using statistical methods(mainly on software)
Enable efficient characterization using limited analytical data.
① Establishment of an analysis database management system(FRAnDLi)② Establishment of statistical inventory estimation methods
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廃棄物対策Technical strategy by3.2
sectorsfor廃棄物対策に係る分野毎の技術戦略
waste management in the future
３．福島第一原子力発電所の廃炉に向けた技術戦略

Characterization➢ It is important to develop a medium-to-long-term analysis strategy that defines the solid
waste to be analyzed, its priority, and quantitative targets for analysis, etc., and toproceed with analysis/evaluation accordingly.
➢ Reasonable number of analyses for large volume low and medium activity waste➢ Characterization strategy for high activity waste that is difficult to sample.

Storage➢ Thorough safe and rational storage.

➢ Secure storage capacity under the limitation of space (volume reduction、limited scope ofdismantling ）Processing/disposal➢ In order to establish safe and reasonable processing/disposal methods, and to widely
obtain knowledge for optimizing each individual waste stream, it is necessary to continue
development/research of processing/disposal technologies required for the series ofstudies.
➢ Secure safety assurance measures for entire waste streams under large uncertainty.

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３．福島第一原子力発電所の廃炉に向けた技術戦略

3.2 廃棄物対策

Diversifying Analysis methods against the requirements for the
廃棄物対策に係る分野毎の技術戦略
managementof retrieved materials

Criticality➢ Shape management or substance quantity management of storage package
based on contents of nuclear material

Safeguards and Nuclear Material Protection➢ Evaluate needs of safeguard and protection based on contents of nuclear
material

Processing/disposal➢ Evaluate needs of processing➢ Allocate to the suitable disposal option
Fuel debris contains difficult-to-measure nuclides, interfering elements,immiscible materials, etc.
◆ Analytical Capability (Facility and Human Resource)◆ Remote sampling technology◆ In-situ analysis and non-destructive measurement methods toimprove analytical results◆ Statistical inventory estimation method
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On Site Analysis Laboratories
JAEA Okuma analysis
and research center

Lab No2

TEPCO Hot Lab inunit5,6

Lab No１

Administration build.
Objectivas:・For R&D of Processing,
Disposal and Fuel Debris
characterization
etcTEPCO
ChemicalLab

Objectivas:
・Discharge water・Sea Water,Fish etc

Objectivas:
・Contaminated water,・Processed water
etc

TEPCO
Environmental
Lab

Objectivas:
・Ground Water
・Soiletc

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Role of Analyses and Investigation results in the Decommissioning Work

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Example timing of in-site analysis and non-destructive measurement in theprocess of fuel debris retrieval to storage phase16

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Concluding Remarks➢ About the 1F solid waste, challenges are the analysis and evaluation
strategy for the high activity waste that is difficult to sample and therationalization of the number of analyses for the large quantities oflow/middle activity waste. A rational characterization method not to beseized with a conventional method is necessary.
➢ In consideration of needs of analyses and the ability of each analysis

facility, to characterize under the clear the role-sharing of relatedorganizations as All Japan is essential for the smooth decommissioning
promotion.

➢ It is necessary each facility secures ability (facilities and person)
necessary for a role, and to cope with the change of needs accompaniedwith the progress of the decommissioning.

➢ The novel technology development with universities very much expected.
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Thank you for your attention!

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