Nuclear Damage Compensation and Decommissioning Facilitation Corporation

Technical Strategic Plan 2020
for Decommissioning of the Fukushima
Daiichi Nuclear Power Station ofTokyo Electric Power Company Holdings, Inc.
(Explanatory Material)
October, 2020
Nuclear Damage Compensation andDecommissioning Facilitation Corporation
NDF
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Table of Contents
1. Introduction
2. Concept on risk reducing and safety assurance for decommissioning of
the Fukushima Daiichi Nuclear Power Station
3. Technological strategies toward decommissioning of the Fukushima
Daiichi Nuclear Power Station(1) Fuel debris retrieval(2) Waste management(3) Contaminated water management(4) Fuel removal from spent fuel pools(5) Utilization of analysis results for smooth promotion of
decommissioning
4. Efforts to facilitate research and development
5. Activities to support our technical strategies(Enhanced project management, strengthening international cooperation,and local community engagement)
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11. Introduction (1/2)
Four key aspects in Strategic Plan 2020
The Strategic Plan 2020 presents mid-to-long-term technical strategy byfocusing on the following four key aspects of this year.
First key aspect In March, Tokyo Electric Power Company (TEPCO) announced its Mid-and-Longterm Decommissioning Action Plan, describing the specific work schedule toaccomplish the Mid-and-Long-term Roadmap.
See pages 3 and 22.

Second key aspect With the trial retrieval of fuel debris approaching very soon, NDF once again reviewed
the safety-prioritized operations and established a new recommendation,“Approach to Ensuring Safety” section.
See page 7.

Third key aspect In further expanding fuel debris retrieval, on the premise of safety as the project
executor, the needs of setting requirements (boundary conditions) in considerationof time, exposure dose and cost with realistic constraints are specified in the section“Fuel Debris Retrieval”.
See page 14.

Fourth key aspect The administrative structure in R&D is enhanced, since the importance of R&D,
particularly that of the Government-led R&D Program on Decommissioning andContaminated Water Management, is growing, in response to unprecedented
difficulties of fuel debris retrieval in the future.
See Page 21.
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1. Introduction (2/2)
Purpose of TEPCO’s announcement of its Mid- and Long-term Decommissioning Action Plan

Government As one of major deliverables in ‘Plan Review including Medium-to-long-term perspectives’, TEPCO
newly provided its “Mid-and- Long-term Decommissioning Action Plan”.
↑ This year’s first key aspect Based on the Mid-and-Long-term Decommissioning Action Plan updated every year, NDF andTEPCO jointly formulate the Withdrawal Plan to promote the project.
 TEPCO’s more active engagement became clear in the project by announcing the Action Plan.
Mid-and-Long-Term Roadmap*
Proposals for Revise* Conti nually revi sed based on the progress of programs,
i n the past revised once a couple of years
Next R&D Plan
(The Government-led R&D program on
Decommissioning and Contaminated Water Management)

NDF

Strategic Plan (a nnual)
The Policy for Preparation ofWithdrawal Plan for Reserve Fund for
Decommissioning (a nnual)

Feedback

TEPCO

Withdrawal Plan for Reserve Fundfor Decommissioning (annual)Joi ntly created with NDF a nd a pproved by METI
• Conta minated water ma nagement PG• Spent Fuel removal PG• Fuel debris retrieval PG• Wa ste management PG• General management of the s ite PG• Fa ci lity ma intenance/Operational Management

Planning from
Mid-and-long-term aspect
Mid-and-Long-term
Decommissioning Action Plan(annual)Announced in March 2020
On-site work

Engineering

Feedback

R&D

Promotion of Decommissioning project

Figure: Positioning of strategic plan
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32. Concept on risk reducing and safety assurance for decommissioningof the Fukushima Daiichi Nuclear Power Station (1/5)
Concept on risk reduction (1/3)
 The interim goal of the risk reduction strategy is to bring risk items into the “Region of
sufficiently stable management (pale blue area).
Major changes from last year

Change 1 : Zeolite sandbags are newly added
into the major risk sources*1

 Zeolite sandbags were installed on the basement
floors of the process main building and the hightemperature incinerator building as contaminatedwater management activities .
 They were identified as miscellaneous risk
sources in the Strategic Plan 2019, and wereadded into the major risk sources in the Strategic
Plan 2020.

Change 1

Change 2 : Treatment of residual water in theflanged tanks has made progress.
Change 2*2

Examples of risk levels of Major risk sources at the
Fukushima Daiichi PS

 Treatment of strontium-treated water remained at
the bottom of the flanged tanks made progress.
 At present, 500m3 of the residual concentrated
salt water is stored only. (As of the end of August2020)*1: An index to show the severity of an event, depending on inventory (amount of radioactive materials), forms of risk source (such as gas, liquid, andsolid), and time allowance to the exposure of risks after loss of safety function*2: An index to show the likelihood of occurrence, depending on the health of facilities and containment and monitoring conditions of risk sources
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42. Concept on risk reducing and safety assurance for decommissioningof the Fukushima Daiichi Nuclear Power Station (2/5)
Concept on risk reduction (2/3)
 There was still significant uncertainty, however, to eliminate uncertainties, many
resources including long time are required. In order to realize prompt risk reduction it isnecessary to make integrated decisions through a flexible and prompt approach,based on the directions determined with previously obtained experiences, placing
safety as the top priority, even though a certain extent of uncertainties remain.
 As the viewpoint to make these comprehensive decisions, NDF summarizes thefollowing five guiding principles:(Five guiding principles)
•

Safe:

•

Proven:•Efficient:•

Timely:•Field-oriented:

Reduction of risks posed by radioactive materials and ensuring of work safety(Issues such as containment of radioactive materials [environmental impact], andradiation exposure to workers, and assessment of risk reduction effects)
Highly reliable and flexible technologies(Issues such as conformity to requirements, effectiveness and flexibility against
uncertainty)
Effective and rational use of resources, including people, things, money, space, etc.
(Issues such as reduction of waste generation, cost, improvement in efficiency, andsecuring necessary work area and site)
Time consciousness(Issues such as early start of fuel debris retrieval and estimation of time required for fueldebris retrieval)Comprehensive three-reality policy by checking actual site, actual goods, and actual situation(Issues such as workability including environment-friendliness, accessibility, andoperability, and maintainability including ease in maintenance and troubleshooting)
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52. Concept on risk reducing and safety assurance for decommissioningof the Fukushima Daiichi Nuclear Power Station (3/5)
Concept on risk reduction (3/3)
 It is important to proceed with the decommissioning operation after greatly
emphasizing on safety assurance for the purpose of protecting humanbeings and environment from radioactive materials associated with theoperations, thoroughly conducting radiological consequence evaluation,and taking appropriate radioprotective measures. (“Safe”)
 While controlling this risk as low as reasonably achievable (“Efficient”) as
promptly as possible (“Timely”) in light of the situation at the site, proceedingwith the decommissioning in a reliable manner (“Proven”) by feasible ways inthe harshest condition on-site (“Field-oriented”) will lead to ensuring safety inmedium-to-long-term.
 As for the result judged based on these guiding principles, it is also important towork to disseminate information carefully so that the results of this judgment
will be widely accepted by society.

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62. Concept on risk reducing and safety assurance for decommissioningof the Fukushima Daiichi Nuclear Power Station (4/5)
Concept on safety assurance (1/2) <= This year’s second key aspect Basic policy for ensuring safety based on the characteristics of Fukushima Daiichi NPS
 “The safety perspective” should be reflected in the decommissioning work review.
• The Fukushima Daiichi NPS containing the reactor involved in the accident is different from that of anormal reactor in that a great uncertainty exists about the status of radioactive materials andconfinement barriers, and on-site access and installation of instrumentation devices to reduce
the uncertainty are also restricted. Under such circumstances, a large amount of atypical andunsealed radioactive materials will be handled in an incomplete containment condition. Therefore,
the starting point for all reviews needs to be confirmation of the feasibility of ensuring safetywith a wide range of possibilities assumed.
• It is important not to prolong the work period, while paying attention to risk reduction over the entire
work period. It is necessary to avoid exceedingly few or excessive safety measures byperforming thorough safety evaluations and to take optimum safety measures (ALARP).
 Ensuring safety by incorporating “the operator’s perspective”• To ensure that safety measures are effective, “the operator’s perspective” (perspectives andjudgements from the standpoint of those who are familiar with the site and perform
operations and tasks on site) is important.
• “The operator’s perspective” is also important from the viewpoints such as enhancement of safety
in total through operations in addition to design and utilization of the information obtained
through on-site operations into designing safety measures.
 It is essential to reflect “the safety perspective” and “the operator’s perspective” to address thecharacteristics of decommissioning of the Fukushima Daiichi NPS.
• In reviewing decommissioning work, TEPCO, as the project executor, should define the“requirements” for the work in advance, and should design specific safety measures to achievethem, taking “the safety perspective” and “the operator’s perspective” into account.
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2. Concept on risk reducing and safety assurance for decommissioningof the Fukushima Daiichi Nuclear Power Station (5/5)
Concept on safety assurance (2/2)
 Preliminary implementation and utilization of the obtained information in thelatter stages
Considering current environment with already high radiation level and further deterioration ofcontainment barrier, it is necessary to improve such risk state and reduce uncertainties
as quickly as possible.
The operation proceeds with its safety ensured through monitoring the condition inside
reactor and restricting operational actions at each stage of the process. Utilizing theacquired information in the design of subsequent stages allows to reduce uncertainties aswell as to improve the reliability of safety assurance and rationalize design.
TEPCO is required to quickly introduce approach like this into actual engineering andproject management. It is important to accumulate experiences acquired in this approach.

 Approach to address a temporary increase in risk level associated withdecommissioning operations
While the decommissioning work is striving for prompt risk reduction, careful deliberation isrequired over the possibilities that the performance of decommissioning work may
temporarily change the risk levels and may increase the radiation exposure of workers.
The possibility of a temporary increase in the risk level must be addressed by taking
measures to prevent and restrict them. It is necessary to operate with thoroughpreparations, in particular, the radiation safety of workers should be ensured inaccordance with the concept of ALARA (to suppress radiation exposure to As Low As
Reasonably Achievable).
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3. Technological strategies toward decommissioningof the Fukushima Daiichi Nuclear Power Station (1/12)① Fuel debris retrieval (1/7)
Targets(1) Retrieve fuel debris safely after thorough and careful preparations, including safety measures, andbring them to the state of stable storage under full management.
(2) Beginning with trial retrieval of fuel debris from Unit 2, the first implementing unit within 2021, thenstart the gradual expansion of fuel debris retrieval and a series of operations timely. Through thisprocess, acquire knowledge and experience necessary for the further expansion of fuel debris retrieval in the
future.
(3) To further expand the retrieval scale, thoroughly examine the result and progress of the fuel debris retrieval
from the first implementing unit, through internal investigation, R&D (the government-led program on
decommissioning and contaminated water management and TEPCO’s voluntary project), on-siteenvironmental conditions. Through this process, study the best methods of contain, transfer, and store.

Figure : Image from retrieval to temporary storage of fuel debris (Gradual expansion of retrieval scale)** Edited by NDF based on TEPCO materials

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93. Technological strategies toward decommissioningof the Fukushima Daiichi Nuclear Power Station (2/12)
Technical strategy① Fuel debris retrieval (2/7)
 Trial retrieval, internal investigations of PCV and gradual expansion of fueldebris retrieval
 Although small in scale, this is a fundamental
form of site construction for future work, inwhich an opening will be newly provided toextend the containment barrier outside thePCV. It is an approach that enters a new stage.
• Containment barrier will be extended fromblank flange part of the penetration X-6 to an
isolation chamber and an enclosure.

Figure 1 : Image of fuel debris retrieval system(Trial retrieval and subsequent gradual expansion)*

Figure 3 Schematic drawing of enclosure
Figure 2 Schematic drawing of Isolation
to be installed at Penetration X-6 *Chamber to be installed at Penetration X-6 *Copyright. All rights reserved.
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3. Technological strategies toward decommissioningof the Fukushima Daiichi Nuclear Power Station (3/12)
Technical strategy① Fuel debris retrieval (3/7)
 Trial retrieval, internal investigations of PCV and gradual expansion offuel debris retrieval
 With regard to the trial retrieval, it is important to conduct a mock-up test simulating
the harsh site environment from the operator's perspective, while adequately
confirming safety and the actual site applicability to steadily proceed.
 It is also important for TEPCO to take the initiative in promoting engineering basedon the considerations related to acquisition and utilization of information during
fuel debris retrieval.
• Due to the restricted attendance of engineers under the influence of the coronavirus,
it is assumed that the planned work would be more difficult than before, andtherefore, more deliberate and careful attention should be paid to ensuringsafety.
 Removal of obstacles, a trial retrieval, and internal investigations of PCV that are
performed after opening the penetration X-6 shall be deemed as integrated work.
• According to the state of obstacles in the PCV and the internal conditions actuallyobtained , the sequence and method of removing obstacles, a trial retrieval, andinternal investigations of PCV may vary depending on the observation results
obtained at that time.
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3. Technological strategies toward decommissioningof the Fukushima Daiichi Nuclear Power Station (4/12)
Technical strategy① Fuel debris retrieval (4/7)
 Further expansion of fuel debris retrieval
 Study flow of the retrieval methods• Operations, devices and equipment, and facilities will be larger in scale and the scope of
construction will be wider than in the case of retrieving fuel debris from the first implementing unit (Unit 2),
much more attention should be paid in overviewing the entire Fukushima Daiichi NPS, including otherworks.
• Because of the high dose on site and the limited understanding of the situation inside the PCVs, the scopeof operations will be enlarged. Therefore, it is important to specify the requirements required for
operations and devices more clearly and to proceed with the study of the systematic retrieval method.
• NDF will evaluate the actual site applicability and feasibility based on the results of TEPCO's conceptual
study.
Status in the improvement ofOn-site work such as
retrieval of fuel debris fromthe initial unit and internal
investigations

 New insight obtained from fueldebris retrieval from the initial
unit and internal investigations

Research and development

 Progress made in research anddevelopment (by the Government-led
R&D program on Decommissioning
and Contaminated Water
Management) and technologicaldevelopment (independently led by
TEPCO)

Evaluation on the review results of the retrieval concept(including the review on the overall concept)
 Requirements
 The methods of retrieval, accessing, and debris recovery
 Safety system
 Storage, transport and storage facilities, etc.

workplace environment
 Status in the on-site environment(radiation dose, water level in PCV) Various new installations (including
buildings)
Prospects of site securing (planning forremoval of obstacles including rubble),etc.

Status of site-wide planning Contaminated water
management
 Plan for solid waste Interference with other works,
etc.

Evaluation on the actual site applicability

 Safety
 Reliable Reasonable Prompt Field-oriented

Comprehensive evaluation
 Comprehensive evaluation from the above perspectives

Figure: Study flow of the retrieval methods (Conceptual diagram)
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3. Technological strategies toward decommissioningof the Fukushima Daiichi Nuclear Power Station (5/12)① Fuel debris retrieval (5/7)

Technical strategy

 Further expansion of fuel debris retrieval
 It is deemed appropriate to consider Unit 3 as a pioneer unit.
• While a trial retrieval will be implemented at Unit 2, it is Unit 1 or Unit 3 that enables easy
access to a large amount of fuel debris, because fuel debris remains in bulk at thebottom of the pedestal of these Units.
• In view of the sufficiency of information and the site conditions, Unit 3 will be able tocommence debris retrieval and obtain information earlier, as it will enable advancementof engineering including study of retrieval method• By setting a certain unit as a representative one, it will enable earlier obtainment oftechnical points and items to be further studied. Utilizing the results in other units willlead to reducing the overall risk of fuel debris in Units 1 to 3.
• While taking a pioneering approach at Unit 3, status of other units and their review results
should be reconfirmed, and the unit under review as a pioneer unit may need to bereconsidered, depending on the outcome.
• Even if the first implementing unit (Unit 2) is in the process of retrieving fuel debris, themethod of proceeding shall be flexibly considered in light of optimizing the overall work,for example, by starting retrieval from another unit that is in preparation for retrieval.
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3. Technological strategies toward decommissioningof the Fukushima Daiichi Nuclear Power Station (6/12)① Fuel debris retrieval (6/7)

Technical strategy

 Further expansion of retrieval scale↓ This year’s third key aspect Concept of important requirements (Boundary conditions) for the retrieval method• When proceeding with the study on retrieval methods, TEPCO is required to clearly
define the important requirements (boundary conditions) as the project executor.
• The important requirements (boundary conditions) shall be stipulated based on thesafety perspective and the operator’s perspective, regarding which requirements to be
defined as important (that is, the boundary conditions) and which level of performance isrequired.
(For example, total exposure dose of workers, criticality, dust (containment), reduction of waste
generation, and recovery rate)• In addition to the requirements illustrated above, TEPCO should more independently
determine various important requirements (boundary conditions) to steadily proceed withstudy on retrieval method.
 A flexible approach in studying the retrieval method• It is required to take a flexible approach including partial improvement of the retrieval
method, according to the assessment of the actual site applicability.
• While establishing preconditions including assumptions and advancing its study, arepetitive and iteration-based approach will be required by incorporating newly obtained
information to verify the appropriateness of the preconditions to be established based on
the safety perspective and the operator’s perspective, and by reviewing it if necessary.
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3. Technological strategies toward decommissioningof the Fukushima Daiichi Nuclear Power Station (7/12)① Fuel debris retrieval (5/5)

Technical strategy
 Key Technical issues and future plans
Short term (approx. 3 years)

Short term (approx. 3 years)

Period 3 - (1) (Starting from fuel debris retrieval up to the end of 2031)

Period 3 - (1) (Starting from fuel debris retrieval up to the end of 2031)
Fiscal Year

2020

2021

2025

2031 (Year)

Fiscal Year

Improve the environment
inside the building

Experimental retrieval and internal
investigations

Manuf acture and install the
retrieval device

Further expansionof the retrieval scale(Units 1/3)

Characterize the f uel
debris

2021

2022

2025

2031 (Year)

Fuel debris retrieval f acility/safety system/fuel debris temporarystorage facility/maintenance facility
Design and production

Improvement of the environment inside and outside the Unit 1 building (Inside of the building: Dose reduction/removalof obstacles; Outside of the building: Removal of exhaust tow ers of Units 1 and 2/removal of transf ormers, etc.)
Improvement of the environment inside and outside the Unit 3 building(Inside the building: PCV w ater lowering/dose reduction; Outside the building: removal of the exhaust tow ers of Units 3 and 4, removal of transf ormers, etc.)
Fuel debris retrieval f acility/safety system/fuel debris storage facility/maintenance facility

Improv e theenv ironment inside
the building

Gradual expansion of retrieval scale(Unit 2)

2020

▽Start of the fuel debris retrieval in theinitial unit (by the end of 2021)

RM milestones

Experimental retrieval(Unit 2)2022

Installation

Review on the concept
Gradual expansion of retrieval scaleTechnical study by TEPCOTechnical study by TEPCO(Trial manufacturing of arms/enclosures --> Use them as a mock-up during training)

Production, installation, and retrieval- Development of technologies to retrieve
f uel debris and internal structures,
addressing a further scale expansion- Development of Technology for Collection,transfer and Storage of Fuel Debris- Development of technology for investigation- Development of Technology for Detailed
Investigation inside PCV- Development of technologies for grasping
and analyzing properties of fuel debris- Development of technology for gradually
expanded-scale retrieval of fuel debris(1) Addressing payload growth and upgrading end tools

Design

Review of the program on
Decommissioning and Contaminated
Water Management and the project
independently conducted by TEPCO

Characterize the f uel debris

Review of the program on Decommissioning
and Contaminated Water Management andthe project independently conducted by
TEPCO- Development of technology for gradually expanded-scale retrieval of fuel debris

Actual site applicability verification,
dev elopment (Remote installation,
dust diffusion control, etc.)- Fuel debris characterization/Development of analysis
technology(1) Advancement of fine particle (dust) behavior
estimation technology(2) Estimation of aging properties- Development of technologies to retrieve fuel debris and internal structures, addressing
a further scale expansion- Development of technology for investigation inside the RPVConstruction method by top/side/bottom-access(1) Development of fuel debris retrieval method (ensuring safety --> higher efficiency)
a. Improvement of installations and devices for access/technology for removing
obstacles/internal audit methodb. Preventing the spread of radioactive materials(1) Technology for removing obstacles, etc, Access device(2) Development of safety systems (liquid and gaseous systems, criticality control)a. Enhancement of the containment of radioactive materials; b. Enhancement of
the removal of radioactive materialsc. Enhancement of criticality prevention/criticality monitoring functions(2) Surveillance devices (camera, radiation detector,
experimental retrieval device, etc.)(3) Preventing the spread of radioactive materials* It is assumed that Unit 3 w ill be examined in advance and expanded to Unit 1.

Fig. 1 Trial retrieval and gradual expansionof fuel debris retrieval

Fig. 2 Further expansion of fuel debris retrieval

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3. Technological strategies toward decommissioningof the Fukushima Daiichi Nuclear Power Station (8/12)② Waste management
Targets(1)

As the approaches to solid waste storage, the Solid Waste Storage Management Plan (“Storage Management Plan”)
is appropriately developed, revised and implemented, including waste prevention, volume reduction and monitoring,
while updating the estimated amount of solid waste to be generated in the next 10 years periodically.

(2)

As an approach to processing/disposal, countermeasures integrated from characterization to processing/disposal of solid
waste are studied from expert point of view, and. the prospects of a processing/disposal method and technology
related to its safety should be made clear by around FY 2021

Technical strategy

Year Promotion of characterization and enhancement ofanalysis system and technical capabilities

Milestones

2015

2016

2017

2018

2019

2020

2021

2022 and later

Obtain technical prospects ofprocessing/disposal methods and their safety,
based on the outputs of studies marked with *Compilation of basic conceptof processing/disposal

1. Waste characterization

 It is important to proceed with human resource(1) Analysis data acquisition, management, etc.Planning/updating analysis plan, conducting analysis, characterization, accumulation/evaluation/management of analysis data
development for analysis in the organized manner as*
Development of radioactive material analysis and research facilities
well as to arrange the Radioactive Material Analysis (2) Improvement of analysis capacity
Human resource development for analysis personnel
and Research Facility and to reflect achievement of(3) Enhancement of efficiency on waste
Optimization of the number of analytical samples, review of nuclides to be analyzed, *simplified and speed-up analysis methods.
simplified and speed-up analysis methods, etc.

 Development of processing/disposal concept andsafety assessment method
 To select candidate technology for preceding
processing method, it is necessary to identify
reasonable and feasible processing technology anddevelop safety assessment technique for disposal
corresponding to such technology.

characterization

2. Storage(1) Storage management plan(2) Study and evaluation of Storage
methods(3) Study and evaluation of Storage methods
for solid waste generated during fueldebris retrieval

Study on Storage measures of secondary waste from water treatment*

Study on safety
improvement
measures

Evaluating of the kind/amount of material, etc.,
and evaluation according to the examination situation of retrieval*
Development of a safety assessment method for disposal methods *Research on theTechnical development of processinhg methods related to*
conditioning techniques
stabilization and immobilization*
Study on processing/disposals
Establishment of a selection
system of preceding procesing

3. Development of processing/disposal The prospects of a proceeding/disposal method and concept and safety assessment methods
technology related to its safety Outlook will be presented by around FY2021 basedon the results of R&D as well as TEPCO'S engineeringachievement.

Development and review of the Storage Management Plan

Establishment of a
selection system ofprocessing/disposal
concept: On-site operation: Technical studies, etc. for the on-site construction, etc., for each item
: Research and development

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3. Technological strategies toward decommissioningof the Fukushima Daiichi Nuclear Power Station (9/12)③ Contaminated water management
Targets(1)

Under three principles for the contaminated water problem (“Removing” contamination sources, “Redirecting” fresh waterfrom contamination sources, and “Retaining” contaminated water from leakage), to reduce the stagnant water in thereactor buildings in FY 2022 to FY 2024 to about the half of the amount of the end of 2020 while continuing theoperation of the constructed water-level management system and controlling the generation amount of thecontaminated water to 100 m3/day or less in 2025.

(2)

To arrange the relationship with a decommissioning process including full-scale fuel debris retrieval beginning in
the near future, and to promote examinations of the measures of the contaminated water management for mid-andlong-term prospects.

Technical strategy

Fiscal year

2021

2022

2025

 To control the contaminated water generation amount to approximately 150 m 3/day (in 2020)
 To complete the processing of stagnant water in the building (in 2020) * Issues in future treatment of stagnant water in buildings*

Related milestones

2031
 To control the contaminated water generation
amount to 100 m 3/day or less(in 2025)

To reduce stagnant water in the reactor building to approximately half that of the end of 2020 (FY 2022 to FY 2024)

Maintenance management operation of a groundwater bypass, a sub-drain, and a land-side impermeable wall

Contaminated water
generation amount

Site pavem ent inside the land-side impermeable wall (sea-side)

Site pavem ent inside the land-side impermeable wall (mountain-side)

Repair broken parts of roofs (incl. the installation of a large cover on Unit 1 R/B)

Stagnant water in buildings

 It is required to strengthen the monitoring of α-nuclides
concentration in each building and water treatment systems as wellas property analysis, while continue R&D to establish a measure
to remove sludge-like sedimentation containing α-nuclides.
 A method to remotely collect and accumulate zeolite existing in ahigh radiation dose are being studied. It is required to select anappropriate method by comprehensively evaluating radiation
exposure dose during work.

 Issues of contaminated water management considering
the decommissioning process such as debris
retrieval

2020

Units 1 to 4 T/B, etc. Water level lowering
Confirmation of stagnant
w ater characteristics

Units 1 to 3 R/B

Water level lowering for a 50% reduction

To implement required measures in accordance with the stage of fueldebris retrieval

Simple measuresagainst α-nuclides

α-nuclides retrieval equipment: Design, manufacture, and installation

Process building
High-temperatureincinerator

α-nuclides removal equipment: Operation

Alternative tank: Design, manufacture, and installation
Zeolite dose mitigation measures/equipment: Conceptual examination, design,
manufacture, installation, and measures
Zeolite stabilization measures: Examination, design, manufacture, installation, and measures
Tide embankment
installation

Building opening closure< Legend>: The period of workof decontamination equipment: Examination, design,
Measures against natural Sludge transfer equipment
The period during which
manufacture, installation, and transfer
 It is necessary to take measures such as enhancement ofchange is expecteddisastersmonitoring of water treatment systems, installation of α-particle
Examination, desig and construction for Tsunami disaster prevention ofJapan Trenchcollection equipment, and criticality monitoring.
 To further expand the fuel debris retrieval, it is required to study
Measures against
stagnant water
Underground water storage tank: Dismantling/retrieval and conceptual examination/design/retrieval
downsizing of equipment considering the installation space,
operation and maintenance under high radiation dose, and*Except Units 1 to 3 reactor buildings, process buildings and high-temperature incinerator building.
utilization of existing purification facilities.
:

Measures for VLFS

Reversing valve pit
blockade

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3. Technological strategies toward decommissioningof the Fukushima Daiichi Nuclear Power Station (10/12)(4) Fuel removal from spent fuel pools (1/2)
Targets
(1)

(2)

(3)

While the return of residents and reconstruction in the surrounding area is gradually advanced, to carry out a risk
assessment and ensuring safety certainly including preventing dispersion of radioactive materials and to start theremoval of fuel in SFPs (spent fuel pools) in FY 2027 to FY 2028 for Unit 1 and FY 2024 to FY 2026 for Unit 2. To
complete the removal of fuel in SFPs in FY 2020 for Unit 3.
The fuel in Units 1 to 4 that were affected by the accident are taken out of the SFPs and transferred to the Common
Spent Fuel Storage Pool, etc., where they are appropriately stored so that they are in a stable management state.
In order to secure the Common Spent Fuel Storage Pool capacity, the fuel stored in the Common Spent Fuel Storage Poolis transferred to and stored in the Dry Cask Temporary Custody Facility.
To carry out the evaluation of long-term integrity and the examination for treatment for the removed fuel and to
decide the future treatment and storage method.

Technical strategy

Crane For Units 1 and 2, it is required to advance the work steadily to realize thedetermined new removal method.
 Unit 1:• From the viewpoint of further reduction of radioactive dust dispersion risk, the whole operating
floor was covered with a large cover. The removal method was changed to one in which rubble
removal and the removal of fuel in SFP are carried out inside the cover.
• The existing collapsed overhead crane must be removed, which remains in an unstablestate. To do so, selection of engineering method and its implementation should proceed after
the thorough safety assessment. Toward its realization, it is essential to formulate a work
plan for identifying risk items.

 Unit 2:• New method that the upper part of the operating floor will not be dismantled and access from thesouth side of the reactor building was adopted from the viewpoint of further reduction ofradioactive dust dispersion risk similar to Unit 1. Preparations are being advanced at present.
• Boom-crane-type fuel handling machine is new to us. So, fully preparation for its operationand functions in advance are crucial, before remotely operating it to remove fuel.

Figure 1 : Image of removal method for Unit 1

Fuel handlingCrane
facility
Fuel handlingmachineWell plug
Spent fuel pool

Front
Chamber

Opening for load in/out

Reactor Building

Figure 2 : Image of removal method for Unit 2

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3. Technical strategy toward the decommissioningof the Fukushima Daiichi Nuclear Power Station (11/12)④ Fuel removal from spent fuel pools (2/2)
 As for removal of fuel assemblies with deformed handle, it
is important to load them reliably into transport cask bylifting safely from fuel rack.
 16 fuel assemblies with deformed handle were confirmed for
Unit 3. (Fig.1)
 Manufacturing of a tool for removing rubbles is now
systematically being prepared.
 It is important to reliably execute the preparations including
verifying in advance, giving these feedback and examining
multiple responses.
Fiscal year

2020 2021 2022

Complete installation of Unit 1
large cover (around FY 2023)

Milestones▽

Rubbleremoval, etc.

Unit 1

2025
Start Unit 2 fuel retmoval(FY 2024 to FY 2026)

2031
Complete fuel removal(in 2031)
Start Unit 1 fuel removal(FY 2027 to FY 2028)

Installation ofa large cover
Removal of rubble, the overhead crane, etc./well plug disposal /decontamination and shielding of an
operating floor/installation of fuel handling machine, etc.

FuelremovalUnit 2

Installation of a working platform on
Yardmaintenance/foundationthe south side and an opening/fuelhandling machine installation, etc.
improvement, etc.

<Legend>: Fuel retmoval w ork: The period during w hichchange is expected: Works other than fuelretmoval: The period during w hichchange is expected

Fuel removal

Unit 3
Units 5 and 6
Peripheral
environment

Common Spent
Fuel Storage Pool
cask

Fuel
removalUnit 6 fuelremovalDismantling of the upper partof Units 1/2 exhaust stack(completed in May 2020)

Suspended while
work is performed

Suspended while
work is performed
at Units 1 and 2

Unit 5 fuel removal

Dry cask manufacturing

Figure 1 Status of 16 fuel assemblies with deformed handle

Transfer from the Common Spent Fuel Storage Pool to the Dry
Cask at the Temporary Cask Custody Area
Expanding of storage caacity in Dry
Cask Tem porary Custody Facility* Source by TEPCO

Figure 2 Major technical issues and future plans
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3. Technological strategies toward decommissioningof the Fukushima Daiichi Nuclear Power Station (12/12)⑤Utilization of Analysis Results for Smooth Promotion of Decommissioning
Significance and Current Status
 It is necessary to establish and develop analysis facilities and functions and to build a system required forhandling of waste or fuel debris.
 TEPCO is planning to establish an analytical facility necessary for smooth performance of routine analyses in
the future.
 As operation proceeds, risk of α contamination intake is supposed to be gradually increased, a bioassay function is planned
to be established.
 The Radioactive Materials Analysis and Research Facility (Facilities Management Building, Building 1, and Building 2)
is being developed by JAEA, to contribute to facilitation of smooth decommissioning, reliable processing/disposal
measures.

 Analysis results are “an important piece” to reduce the range of uncertainties for the smooth decommissioning.
 Important basic information for the study on processing/disposal measures for various kinds of waste generated by the accident.
 Analyses are reflected in a number of areas, including retrieval methods, storage, processing/disposal, and enhancement of
nuclear safety.

Issues and Strategies
 Analysis shall be positioned at a higher level in the decommissioning project.
 Analytical data plays an important role in the study on the method to mitigate excessive safety design while ensuring safety.

 Consideration should be given to securing and retaining of the analytical engineers.
 It is important to pursue a reasonable analysis plan by comprehensively utilizing analysis results and on-site
information.
 An important stance is that the decommissioning work shall be implemented on schedule by conducting analyses without
delay.
 Taking note of the fact that analysis results have functions to benchmark the estimation results of internal conditions given by
instrumentation monitoring, visual observation, in-situ measurement, and evaluation of calculations (simulation).

 TEPCO should establish a system where TEPCO itself will actively commit control and leadership of thewhole of activities related to the analysis.
 TEPCO is required to start examining the overall strategy and a plan for the analysis of decommissioning work as early as
possible.
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4. Efforts to facilitate research and development
 Strengthening the research and development management organization in the
Government-led R&D program on Decommissioning and Contaminated Water
Management <= This year’s fourth key aspect
 Trial retrieval in 2021 is approaching. Soon thereafter, for expanding the retrieval scale, the organization
was strengthened as we recognized the need to accelerate R&D.
 Changes due to the organization strengthening
・ Change 1: NDF participated in the secretariat of the Government-led R&D program on
Decommissioning and Contaminated Water Management.
・ Change 2: TEPCO jointly applies for subsidy with R&D implementation entities.

 Formulating the R&D medium-to-longterm plan

Ministry of Education, Culture, Sports,
Science, and Technology

Government-led Project ofDecommissioning andContaminated Water
Management

Support*8

Operating costsubsidy

AssistanceFund establishment corporation

Change 1
Participation

Secretariat

Project
implementation

Subsidized company

 Up to date, good results have been obtained fromthe World Intelligence Projects of MEXT and
JAEA/CLADS and it is important to accelerate toreflect directly in the decommissioning site.
 Based on those results, new joint research
between four universities and TEPCO has
started last year. Continuous enhancement ofcollaboration with related institutions is needed.

Othermakers, etc.
(including
overseascompanies)

International ResearchInstitute for Nuclear
Decommissioning

Joint application, etc.

 Matching of needs and seeds ofdecommissioning work sites anduniversities/research institutions

Decommissioning R&D
Partnership Council*1(Constitution)
NDF, JAEA, the Tokyo Electric Pow er Company, IRID,
plant makers, related experts, the Ministry of Economy,
Trade, and Industry, the Ministry of Education, Culture,
Sports, Science, and Technology

National Research and
Dev elopment Agency
Plants, manuf acturers, etc.
Electric power companies,
etc.

Sharing and planning oftechnical development
information

Cooperative relation

Foreigngovernmentorganization

Naraha Remote Technology
Dev elopment Center

Okuma Analysis andResearch Center

Administrative
instructions

CLADS

*6
Examination request
and support

Change 2 TEPCO

Project
implementation

A company
making a contract

Project Management
Operation

Participation

Cooperation

Secretariat

Consignment
and joint
research

Exchange of research needs
and seeds
Bridge-building for results

Holdings

Consignment*7
Assistance

Fukushima research anddevelopment department

Technical committees for decommissioning, etc.

Assignment

Assistance

JAEA

NDF

Fund for Countermeasures for Decommissioning
and Contaminated Water Treatment

World Intelligence Project for Nuclear
S&T and Human Resource
Development

Support*9

Cooperative relation

 Formulation of the Next-term R&D plan based on
new R&D medium-to-long-term plan will clarify
how and where each development corresponds
to the decommissioning process. The plan will
be updated and expanded every year.

Ministry of Economy, Trade,and Industry

Basic research for decommissioning
Platform

Universities,
research
institutions,etc., in
Japan

Joint
research

Overseas
universities
and research
institutions

Companies in Japan andoverseas companies*1 The Decommissioning R&D Partnership Council is established in the NDF based on the determination by Team for Countermeasures for Decommissioning and Contaminated Water Treatment.
*2 The arrow draw n in a thick solid line indicates expenditures such as research expenses and operating expenses (excluding facilities expenses), the arrow draw n in a thin solid line indicates a cooperative relation, etc., and the arrow draw n in adotted line indicates the participation in the Decommissioning R&D Partnership Council.
*3 Some organizations such as JAEA are located at tw o or more places.
*4 Each organization has cooperative relations w ith foreign organizations based on MOU, etc., respectively.
*5 Research and development uniquely conducted by the Central Research Institute of Electric Pow er Industry, etc., are omitted in this figure.
*6 Although among the World Intelligence Project f or Nuclear S&T and Human Resource Development the part adopted up to FY 2017 is the consignment from the Ministry of Education, Culture, Sports, Science, and Technology to a company
making a contract, it is omitted in this figure.
*7 Although the subsidy for the World Intelligence Project for Nuclear S&T and Human Resource Development is delivered to JAEA, it is expressed as w hat is delivered to CLADS, to make it easier to understand.
*8 With regard to the Government-led Project of Decommissioning and Contaminated Water Management, based on the policy in the Mid-and-Long-ter m Roadmap or Strategic Plan and the progress situation of research and development, the NDF
formulates a draft plan of the next research and development, and the Ministry of Economy, Trade, and Industry determines it.
*9 The NDF participates as a member in a steering committee of the World Intelligence Project for Nuclear S&T and Human Resource Development.

Fig. 1 The outline of the decommissioning research andFigure: Overview of the R&D structure of the decommissioning ofFukushima Daiichi Nuclear Power Station (FY2020)

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5. Activities to support our technical strategies (1/5)
Enhanced project management (1/3)
 Formulation and announcement of the Mid-and-Long-term Decommissioning Action<= This year’s first key aspect
Plan TEPCO announced it to make the decommissioning project transparent to local community and society andto tackle decommissioning independently, while materializing the complicated work prospect over a long
period.
 The meaning of announcing the Mid-and-Long-term Decommissioning Action Plan was significant, because it
would enable medium-to long-term planning in R&D, HR, and procurement. In the future, it is also important tomake constant review based on new knowledge and on-site conditions.

 Further strengthening of project management
 In April 2020, TEPCO converted the decommissioning project into a project management type by changing theorganization of Fukushima Daiichi D&D Engineering Company.
 While further strengthening the project management system as well as integrally managing engineering andR&D, it is necessary to implement appropriate and efficient project operation.

 Reinforcement of “safety and operator’s perspectives” in project activities
 To realize the results, it is indispensable to fully reflect safety and operators’ perspectives in the construction
method and equipment.
 A business process to incorporate safety and operator’s perspectives in the upstream of project activities
needs to be established at an early stage.

 Promulgating the “Safety First” principle that safety perspective comes first It is important that all who work in the processes (projects) leading up to the realization of methods andinstallations on the site, keep the safety perspective first in mind as they engage in their work (safety first).
 Leaders of nuclear operations at TEPCO have worked hard to raise awareness on the issue of nuclear safety. In
order to thoroughly promulgate the “safety first” principle to all persons who work on projects including
on-site, it is important to have the attitude to reiterates the special nature of nuclear safety and how it must
be approached with an accordingly special kind of awareness.
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5. Activities to support our technical strategies (2/5)
Enhanced project management (2/3)
 Improving the owner’s engineering capabilities
Importance of “safety and operator's perspectives” in Owner's Engineering of “safety•andPerformancerequirements
need to be carriedby iterationEngineering
to some extent, it is strongly required that
operator's
perspectives”
inout
Owner's
TEPCO “makes a judgment on engineering and is responsible for the results”. It is required to improve theengineering capability (owner's engineering capability) implemented independently by TEPCO as anowner.
• The most important thing in Owner‘s
Engineering is to incorporate “safety andConceptual review
operator’s perspectives” as upstream as
possible in engineering.
Setting boundary condition
from "Safety perspective
and operators' perspective"◎ Operator Requirement Specifications〇 Performance requirements(Functional requirements if unable toindicate here)a) Safery : Criticality, exposure ・・・b) Operability : ・・・c) Easy of maintenance : ・・d) ・・・〇 Verifying perfomancea) Safery : Criticality, exposure ・・・b) Operability : ・・・c) Easy of maintenance : ・・d) ・・・〇 Quality assurancea) QA planb) Sub-vendor list (below secondary
contractorsc) Procurement control for subvendor (specially foroverseas vendors)

Elaborated boundary condition based on "Safety
perspective and Operators' perspectives"： Design process of actual equipment： R&D Process

Input

Confirmation on how the "Safety

Output 1 perspective and operators'

perspectives“ are being reflectedusing deliverables (document)

Actual machine

R&D◎ Conceptual review drawingsand docments• Performance requirements
confirmation document• Safety assessment document(Criticality, exposure, dust
dispersion, heat removal ...）

◎Specifying development
specifications• Identify technical issues andtechnical trend(Technical matuarity)①〇〇 Developed②△△ In the practival application
stage
・・・
• Method developed②・・TEPCO's voluntary PJ by 〇〇③・・Government-led PJ by 〇〇 ・Specification developed
Budget, schedule…

Route 1

• Conceptual
review
redoneNo
Route 2・ Performancerequirements revised
・ On-site investigation
added to reduce
uncertainty

Output 2

All the performancerequirements
satisfied?

Conceptual
review
redoneYes
Elaborated boundary
condition further

Incorporating R&D results

Next step (basic design, etc.)
Route 3• The status of satisfaction can be left as
pending and verification on whether
they satisfy persormance requirements
may be performed at a later date in the

Output◎ Basic design drawing• System design
specifications• Machine design
specifications• Shielding calculation
sheet• P&ID•…

Confirmation of how the"Safety perspective andoperators' perspectives"
are being reflected using
Basic design drawing

Figure. Design flow of fuel debris retrieval (Image)
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5. Activities to support our technical strategies (3/5)
Enhanced project management (3/3)
 ALARP judgment based on safety
 For safety, there is a range of choices at levels above the level that meets a minimum level, construction
methods and equipment to be adopted will be determined based on the judgment of ALARP*.
 In determining them, it is important to decide through the cycle of “define the safety standards (safety
perspective)”, “indicate the feasibility on site (operators’ perspective)”, and “examine and discuss at
project (project management)” The operator's perspective is necessary to actually incorporate the safety perspective into the site, andthe judgment based on the safety perspective is needed to utilize the operator's perspective.
(1) Define the safety
standards

Options for retrieval
methods andequipment that meet
safety standards* It is that radiation impact must be as low
as reasonably achievable.

Communicate retrieval methods
and equipment proposals(2) Examine and discuss(3) Examine feasibility
methods and equipment
on-site (by experts).
to be adopted in the(Operator’s
perspective)
project (ALARP)[4] Determine retrieval methods
and equipment at the project.

Inform advisability(if possible)(Safety perspective)

Inform advisability(if not possible)

Fig. 26 ALARP judgement that reflect the
viewpoint in the field (image)

Figure. ALARP centered on safety (Image) Development based on the Mid-and-Long-term Decommissioning Action Plan
 It is important to assume occupational categories and the number of engineers and the time to berequired in the future in light of the Mid-and-Long-term Decommissioning Action Plan, to summarize
them as the medium-to-long term human resources development plan, and to promote human resources
development and staff securing systematically.
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5. Activities to support our technical strategies (4/5)
Strengthening international cooperation

Significance and the current status of international cooperation
 To promote the decommissioning of Fukushima Daiichi Nuclear Power Station in aninternationally open manner, NDF is making efforts to provide information on thedecommissioning by giving speeches at international conferences.

Dissemination of information to the international community and efforts tointegrate wisdom and knowledge from around the world While engineering is put into practice, it is necessary to make efforts for continuous
communication with the private sectors, and form an environment in which required
technology is accessible when required while sharing information on the progress of
decommissioning work.

Figure Presenting at a side event of the IAEA
General Conference (September 2019)
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5. Activities to support our technical strategies (5/5)
Local community engagement
3-year procurementplan Basic approachThe confidence from the communities is indispensable and various efforts are
made under the fundamental principle of “coexistence of reconstruction
and decommissioning.

TEPCO
Mid-to-long-term
perspective
Recent •initiatives•

 Specific measures under the current situation

While obtaining the Fukushima Innovation Coast Framework Promotion
Organization's cooperation, TEPCO held a decommissioning project matching
event for local businesses.
At the end of March 2020, TEPCO formulated the “commitment toFukushima residents for the coexistence of reconstruction anddecommissioning (Commitment) summarizing the efforts, such as theparticipation of local businesses in decommissioning project, the attraction ofcompanies outside the area, human resources development.
To strengthen the organization, TEPCO established Promotion of Partnershipwith local communities Group under the Fukushima Daiichi D&D Engineering
Company in April 2020, as well as Hama-dori Decommissioning Industry
Project Office under the direct control of the president in October 2020.

3-year procurement plan was announced (Made in every April)
Briefing for enterprises through mid-to-long-term overlook (Held in April 2020)

Government-private
Sector *1
TEPCO
Fukushima ICP *2
Promotion Organization

Cooperation



Local
Enterprises

Businessnegotiations

Consultation
service

Local
Enterprises*1 Fukushima So-So (Soma and Futaba regions)Reconstruction Promotion Agency*2 Fukushima Innovation Coast Framework Promotion Organization

Recentinitiatives• Holding business negotiations for local enterprises(1st:Dec 2019, 2nd:Feb 2020)• Arranging consultation service/tool for local enterprises
seeking to enter the business (Established the counter in May 2020)

Figure : Example of commitment to Fukushimaresidents for the coexistence of reconstruction
and decommissioning(TEPCO materials edited by NDF ) TEPCO must not end “Commitment” just as a shape, but secure effectiveness.






After subdividing the Medium-to-long-term outlook in the decommissioning project as well as the detail, timing and scale ofthe project orders to be placed as much as possible, TEPCO formulated “Medium-to-long-term outlook in thedecommissioning” that specifically states equipment or technology required for each project.
TEPCO will positively provide coordination with the local communities by carefully explaining it via the local governmentsor the association of commerce and industry, through dedicated joint consultation centers and business fairs for local
companies.
By promoting the participation of the local companies including technical guidance, TEPCO makes efforts to build afoundation for the local economy and to foster local businesses and human resources through the decommissioning
project.
It is required to develop the necessary environment and support so that external human resources can fit into theregional society and play an active role. As for the environmental improvement, in particular, it is necessary to consider awide range of living functions so that their whole family can stay with peace in mind.
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