TEPCO HD Press Briefing at Foreign Press Center Japan

Fukushima Daiichi Nuclear Power Station
Fukushima
DaiichiUpdateon Decommissioning
Efforts to
10 years
on Handlingsince theof
accident
Decommissioning
and the
ALPS Treated Water(Tokyo Electric Power Company Holdings, Inc.)
October 24, 2022
Akira ONO

Chief Decommissioning Officer (CDO), President of Fukushima Daiichi Decontamination andDecommissioning Engineering Company, Tokyo Electric Power Company Holdings , Inc.

Junichi MATSUMOTO

Corporate Officer, General Manager of Project Management Office, Chief Officer for ALPS treated water
management, Fukushima Daiichi Decontamination and Decommissioning Engineering Company, Tokyo
Electric Power Company Holdings, Inc.

※October 26, 2022 Correction of error1October 26, 2022 Correction of error

Correction details

Error
Page 9It is necessary to respond to the imminent tsunami emergency. Countermeasures against Outer Rise
Tsunami and Chishima Trench Tsunami were implemented to prevent any increase in stagnant water due
to inflow into the buildings and alleviate damage to important facilities for decommissioning by
suppressing flooding by tsunami. （Completed in FY 2019）
Correction
Page 9It is necessary to respond to the imminent tsunami emergency. Countermeasures against Outer Rise
Tsunami and Chishima Trench Tsunami were implemented to prevent any increase in stagnant water due
to inflow into the buildings and alleviate damage to important facilities for decommissioning by
suppressing flooding by tsunami. （Completed in FY 2020）

Outline

I. The status of Fuel removal from spent fuel pools andFuel debris retrieval at Unit 1/2
II. Initiatives for the handling of ALPS treated water andactivities to foster understanding2

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPS

Main decommissioning work and steps
Fuel removal from the spent fuel pool was completed on December 22, 2014 at Unit 4 and on February 28, 2021 at Unit 3.
Work continues sequentially toward the start of fuel removal from Units 1 and 2 and debris (Note 1) retrieval from Units 1-3
Note 1) Fuel assemblies having melted through in the accident.

＜Milestone in the Mid-and-Long-Term Roadmap ＞

Units 1 and 2

Fuelremovalfrom spent
fuel pools

Units 3 and 4

Ru b b le r emova l etc .

In s talla tion off u el r emova leq u ip ment

Units 1 and 3

Dismantling
Facilities

Within 2031

Unit 1

Start of fuelremovalFY2027 FY2028

Unit 2Start of fuelremovalFY2024 FY2026

Stor a ge /Tr a n s p or tation

Fu el d eb r is
r etr ieva l

Des ig n a n d
ma n u facturing ofd evic es / eq u ip ment

Sc en a rio d evelop men t &tec hn ology c on s ideration

First
unit

Start of fuel debris
retrieval

Unit 2

Within 2021

*To increase the safety andreliability of the work, theprocess was revised to start in
the latter half of FY2023.

Dis ma n tling

Dome roof

Operating floor
Front chamber

Spent Fuel Pool
(SFP)

FuelhandlingmachineCrane

Removed fuel (assemblies)

566/566

Cover bag

(Fuel removal completed
on February 28, 2021)

ShieldShieldFHM girder

Removed fuel (assemblies)

1535/1535*1（(Fuel removal completed on December
22, 2014)

Water
injection

Water
injection

Water
injection

Freezing started
on March 31,
2016

Suppression
chamber

Fuel debris*1 Including
two new
fuelassemblies
removedfirst in 2012.

Cover forfuelremoval615

392

Pedestal

Primary
Containment
Vessel(PCV)ReactorPressure Vessel(RPV)

Completion offuel removal

Unit 2Un d er standing the s itu a tion in s id e thePCV / Con s id eration of r etr ieva lmethod s , etc .

Fuel Debris
Retrieval

Stor a ge /Tr a n s p or tation

Fu el r emova lUnits 1-6

Installation offrozen pipes

1568/1568

Reactor Building (R/B)

Unit 1

Unit 2

Unit 3

Unit 4

Installation of frozen
pipes completed on
Nov 9, 2015

Land-side
impermeabl
e walls

安全第一
福島第一

3

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPS

Status of Work（Spent Fuel Removal ①）

Fuel removal from spent fuel pool [Unit 1]
In preparation for the start of fuel removal between FY2027 and FY2028, a large cover is being installedover the reactor building to suppress dust dispersion during rubble removal, build a working
environment, and suppress the inflow of rainwater.
Temporary gantry and lower structure were installed, and the groundwork for the upper structure
is approx. 50% complete.
▽Start of fuel removal(FY2027-2028)▽Complete of installation of the large cover (Around FY2023)

STEP1
Large cover installation
Temporarygantry(100%)

Rubble removal etc.
Lower
structure(100%)

Upper structure

STEP4

STEP3

STEP2

Upper
structure（50％）

Decontaminationand shielding

Installation of FHM

Rubble removal
overhead cranes

Box ring【Large cover to be installed】
N

Large cover
Movable roof
Approx.
65m

Temporary gantry

Approx.
50m

Anchor・Base Plate＜Work outside the site (August 8, 2022)＞

Movable roof

Box ring
Upper
structureLower
structure
TemporarygantryThe large cover is a steel
structure consisting of alower structure, upper
structure, box ring, andmovable roof, which isanchored to the reactor
building at the location of
the lower structure.

＜ Schematic diagram of the entire large cover ＞＊*The illustration is for illustrative purposes only and may differ from the actual.

4

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPS

Status of Work（Spent Fuel Removal ②）

Fuel Removal from Spent Fuel Pool [Unit 2]
In preparation for the start between FY2024 - FY2026, removal of FHM control room in the building and thegantry foundation installation work are underway.
＜In the building＞

From May 2022, the FHM that parked above the spent fuel poolhas been moved to the north side of the operating floor ※1. In
August, removal of FHM control room was started.
※1 Top floor of the reactor building

FY2021
Decontamination（Part １）

FY2022▼Present
DecontamiShield Installation Interfering Object
nationRemoval（Part １）
（Part ２）【Gantry for Fuel Removal to be installed】

We plan to carry out fuel removal work by moving thefuel handling equipment in and out from thefuel removal gantry to be installed on the south
side of the reactor building.

FY2023
ShieldInstallation（Part ２）

＜Outside the building＞

Excavation work was completed in June 2022. From June 16,
the gantry foundation installation work is underway.

Reactor
Building

Fuel Handling Equipment▼Present
Interfering
objectremoval work

Groundimprovement
preparatory work

Groundimprovement
work

Gantryinstallation
work-Interfering
object removal-Removal of
OF cables-Placing MMS-Roadbed
preparation-Groundimprovement-Foundation
Installation-Steel frame
erection

Gantry for Fuel Removal＜Conceptual drawing of Gantry＞

5

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPS

Status of Work（Fuel Debris Retrieval ①）

Estimated Distribution of Fuel Debris
In order to prepare for the fuel debris retrieval, distribution of fuel debris in the primary containment
vessels (PCV) was estimated after conducting robot investigation, accident progression analysis, muon
investigation, etc. Considering the results of these investigations, Unit 2 has been selected as the firstunit from which fuel debris will be retrieved.

Pedestal
X-100B

TelescopicDevice

X-6

X-53

CRD rail

Unit 1

Unit 2

Unit 3

It is estimated that almost all of
the fuel debris has fallen to thebottom of the PCV.

It is estimated that a part ofmelted fuel has fallen to thelower areas of RPV and PCV,
and a part of it is still remaining in the reactor core.

It is estimated that the situation isintermediate between Units 1 and 2.

6

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPS

Status of Work（Fuel Debris Retrieval ②）Work in Preparation for Fuel Debris Retrieval [Unit 2]
格納容器の壁Work related to fuel debris retrieval from Unit 2 is to be
started in the form of a trial retrieval.
We plan to insert a British-made robot arm through a penetration hole of the containment vessel asan access route to retrieve granular fuel debris on a very small scale. Currently, through mock-up
tests, we are working on improvements such as modifying the control program.
In order to increase the safety and certainty of the trial retrieval work, we added a preparation periodof one to one and a half years, and revised the process to start the trial retrieval work around thesecond half of FY2023.

X-6 penetration
connection structure
Double arm
manipulator

1st floor grating
CRD rail

Robotic arm(when retracted)
Enclosure
Connection pipe

Robotic arm（during investigation)
CRD Housing
Pedestal

X6 penetration
PCV
Pedestal opening（ground floor）

Conceptual drawing of a robotic arm working through a pedestal opening
A robot arm being adjusted at a mockup facility
Source：IRID

7

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPS

Status of Work（Fuel Debris Retrieval ③）

Work in preparation for Fuel Debris Retrieval [Unit 1]
In preparation for fuel debris retrieval, we conduct internal investigations using remote-controlled robots (ROVs) that aresuitable for use.
As a result of the investigation inside the nuclear reactor containment vessel (PCV), large areas of clump-like and shelf-like
deposits are confirmed. In addition, it was confirmed that there was no concrete on the wall of the pedestal opening, andreinforcing bars, etc., were exposed.
Based on current information etc., we have considered the impact of pedestal damage on the plant, and believe thatthe possibility of large-scale damage due to an earthquake is low.
Approx.
1.4m

Investigation
direction
ROV

Powder-like/mudlike deposits

PCV floor

Approx.
1.0m

Reinforcing bars are exposedsince concrete is missing

Deposits thatare crumbled

Board-like/clump- likedeposits

Pedestal opening wall
photographed by ROV

Pedestalfoundation(Reference) Seismic performance and impact assessment of
the pedestal by IRID
Assumed range of pedestal damage

sediment that looks
like it's crumbled

Floor debris
distribution through
MCCI analysis

Deposits photographed by ROV：no damage：damaged

Assuming that the contact point
between the pedestal and molten
debris is missing：not confirmed未確認：exposed reinforcing bars※：no exposed reinforcing ※Beneath deposits
bars※

yet to be confirmed

Exposed reinforcing bars confirmed at this time
are included in the assumed damage range

Investigation results inside PCV(exposed reinforcing bars)

8

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPS

Status of Work（countermeasures against Tsunami）

Installation of Japan Trench Tsunami Seawall
格納容器の壁Countermeasures against Outer Rise
It is necessary to respond to the imminent tsunami emergency.
Tsunami and Chishima Trench Tsunami were implemented to prevent any increase in stagnant water due to
inflow into the buildings and alleviate damage to important facilities for decommissioning by suppressing
flooding by tsunami. （Completed in FY 2020）

In addition, a new seawall is being installed as a facility against the Japan Trench tsunami. Work isunderway for completion in FY2023, and installation of the seawall is approximately 30% complete.
（As of September 2022）
Japan trench sideＮ

【Picture ①】【Picture ②】

Unit 1

港湾側

legendSlope reinforcement
Main body of seawall
Access road

Unit 2

Unit 3

Unit 4

Unit 1-4 side

【Picture ①】
Main body of seawall
under construction（2022.9）【Picture ②】
North side seawall
under construction（2022.8）

防潮堤本体部
Main body of
法面補強部
seawall
2.5m area
Slope Reinforcement

Harbour side

Flap gate
Modification part

Main body ofseawall9

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPSInitiatives for the handling of ALPS treated water
Regarding the discharge of the ALPS treated water into the sea, we will ensure the safety of the public, surrounding environment aswell as agricultural, forestry and fishery products through compliance with safety standards based on relevant laws and legislations. We
will take further measures based on international standards and practices to confirm the safety of the water to be discharged.
We have further expanded and strengthened our sea area monitoring efforts to minimize the adverse impacts on reputation.
Measurements and assessments by third parties will also be disclosed. We continue to work on safety review by the IAEA, anddisseminate accurate information in a highly transparent manner.

The status of approval, etc.
At the fifth Inter-Ministerial Council for Contaminated Water, Treated Water and Decommissioning Issues held on
April 13, 2021, a decision was announced about the government’s basic policy on the handling of ALPS treated waterat Tokyo Electric Power Company Holdings’ Fukushima Daiichi Nuclear Power Station.
On April 16, 2021, we published “TEPCO Holdings’ Action in Response to the Government’s Policy on the Handling of
ALPS Treated Water from the Fukushima Daiichi Nuclear Power Station.”
In December, 2021, TEPCO submitted the "Application Documents for Approval to Amend the Implementation Plan
for Fukushima Daiichi Nuclear Power Station Specified Nuclear Facility" regarding the design of ALPS Treated Water
Dilution/Discharge Facilities, etc. to the Nuclear Regulation Authority (NRA), and on July 22, 2022, these application
documents were approved by the NRA.
On August 2, 2022, Fukushima Prefecture, Okuma Town, and Futaba Town granted us the prior consent after
confirming the state of the necessary safety measures based on the "Agreement to Ensure Safety in Surrounding
Areas Related the Decommissioning of Fukushima Daiichi Nuclear Power Station.

Preparation status of ALPS treated water dilution/discharge facility, etc.
Based on the prior consent (see above), construction of the discharge tunnel began on August 4,
using a shield machine to excavate the bedrock layer.
Preparation work for the installation of partitioning weir in the Unit 5/6 intake open channel is also
underway.

Shield machine

Wall of discharge tunnel

10Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPS

Key Points for the Handling of ALPS Treated Water ①

11

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPS

Key Points for the Handling of ALPS Treated Water ②①Secondary treatment facility

Secondary treatment facility（newly installed
reverse osmosis membrane facility）

Radioactive materials other than tritium in thewater stored in the tanks will be purified as
many times as necessary until they arecertainly below the regulatory standard value
for safety at the pre-discharge stage.

Secondary treatment facility (ALPS)
ALPS treatedwater, etc.
tanks

12

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPS

Key Points for the Handling of ALPS Treated Water ③②Measurement/confirmation facility
After homogenizing ALPS treated water, we will discharge only the water
which be below the regulatory standard value for safety confirmed
Designand operations
ALPS
water
discharge
through themeasurement
and assessmentfor
by notonlytreated
TEPCO but
also the(blueprint) (2)external agencies.

Measurement/confirmation facility
Transfer pumpRotation
Discharge

ALPS treatedwater, etc.
tanks

Measurement/
Receiving confirmation

Seawatertransfer pump③Emergency isolation valve
In the event of an abnormal dilutionof ALPS treated water, emergency
isolation valve will be closed.

Emergency isolation valve

13

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPS

Key Points for the Handling of ALPS Treated Water ④

ALPS treatedwater, etc.
tanks

Seawater transfer
pumpEmergency isolation valve

Seawater flow meter

Seawater transfer pump
Seawater used for dilution

Discharge
vertical shaft

Discharge tunnel(approx. 1km)

④Amount of ALPS treated water to be discharged
Three pumps with a capacity of approx. 170,000 m3/day each will be prepared so that the tritium
concentration after dilution with seawater will be even greater below 1,500 Bq per liter.
We will discharge ALPS treated water while ensuring that the tritium concentration will be less than
1,500 Bq/L and the total amount of tritium to be discharged for a year will be less than 22 trillion
Bq. It will be as small as possible to the extent that it does not interfere with decommissioning.

14

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPSInitiatives for the handling of ALPS treated water ①

Results of the Radiological Impact Assessment
We have conducted a radiological impact assessment on the public and the environment regarding thedischarge of ALPS treated water into the sea using the assessment methodology developed inaccordance with internationally recognized methods. The assessment found that effects of thedischarge of ALPS treated water into the sea on the public and the environment is minimal.
Results of the assessment on the public found that the exposure dose was approx. 1/30,000 to approx.
1/3,000 of dose limit for the general public (1 mSv/year), 0.00003 ～ 0.0004 mSv/year. (X ray exam at
the dentist : approx. 0.01 mSv)

15

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPSInitiatives for the handling of ALPS treated water ②

Results of dispersion simulation at sea
If the diluted ALPS treated water is discharged at the undersea tunnel exit approximately 1 km off thecoast of TEPCO’s Fukushima Daiichi Nuclear Power Station (FDNPS), the simulation (annual average)
found that the area assessed to have higher tritium concentration on the surface layer than current levelsin the surrounding sea area (0.1 to 1Bq/L) will be limited to the area of 2 to 3 km from the FDNPS for
the annual average.
The concentration swiftly falls in areas directly above the undersea tunnel exit and is significantly below
the WHO Guidelines for drinking-water quality (10,000 Bq/L).

16

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPSInitiatives for the handling of ALPS treated water ③

Securing objectivity and transparency
TEPCO was reviewed by the International Atomic Energy Agency (IAEA) on the safety aspects of handling of ALPS
treated water at the Fukushima Daiichi Nuclear Power Station in February 2022. In April of the same year, the IAEA
published a report on its review.
The report states that in regards to the safety of the facilities, the IAEA has found that, “…TEPCO successfully
incorporated prevention measures in the design of the facility as well as in the associated operatingprocedures.” And, in regards to the radiological impact assessment, “…Task Force acknowledged the comprehensive
and detailed assessment that was undertaken in the conduct of the REIA,” adding that, “…the doses to the assumed
representative person are expected to be very low and significantly below the dose constraint set by theregulatory body (NRA).”In March, we set the monitoring plan with additional measurement points and measurement targets and increased
frequency in order to strengthen the monitoring of the sea area as the main entity implementing the ALPS treatedwater discharge. In April, sample collection began in order to continuously confirm the diffusion status, mainly oftritium, and the status of marine organisms before the start of the discharge.
In addition, in order to show the status of the monitoring in an easy-to-understand manner, Treated water portal site
was renovated in September, and a page for sea area monitoring was added. (Japanese version only, English version
in preparation)

IAEA Review Conference in FebruaryPart of a leaflet outlining the IAEA review mission

17

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPSInitiatives for the handling of ALPS treated water ④

Status of the marine organisms rearing test
After accumulating rearing know-how through the rearing practice that has been conducted since
March 2022, in October of the same year, we started rearing tests in both "seawater" and "ALPS treatedwater diluted with seawater" (currently only for flounder, but abalone and seaweed will also be tested in
the future).
We are posting the situation daily (weekdays) on Twitter (in Japanese only) and on our website. We
also provide live streaming of rearing tests on YouTube (in Japanese only).

Marine organisms
rearing tests
Live Camera(in Japanese only)
Marine organism rearing tests ①

Marine Organism
Rearing Log

Marine organism rearing tests ②

18

Progress Status of the Mid-and-Long-Term Roadmap toward Decommissioning of Fukushima Daiichi NPSInitiatives for the handling of ALPS treated water ⑤

The status of activities to foster understanding
We provide accurate and easy-to-understand information not only in Japanese, but also in English,
Chinese, and Korean, using various contents such as our website "Treated Water Portal Site", videos, andleaflets to deepen the understanding of a wide range of people domestic and abroad. We also make atour to the site to deepen the understanding of people in Fukushima Prefecture as well as domestic andabroad.
【Treated Water Portal Site】
The website "Treated Water Portal Site" provides
comprehensive information on ALPS treatedwater, including the current status of ALPS
treated water, QA, leaflets, etc.
https://www.tepco.co.jp/decommission/progress/watertreatment/【TEPCO Shorts ALPS treated water】
TEPCO Shorts ALPS treated water (one-minuteexplanatory video) answers various questions
about ALPS treated water.
https://www.tepco.co.jp/en/decommission/progress/watertreatment/lin
k/index-e.html【INSIDE Fukushima Daiichi】
The Virtual Tour INSIDE FUKUSHIMA
allows visitors to experience thedecommissioning of the Fukushima Daiichi
Nuclear Power Plant on the web.
https://www.tepco.co.jp/en/insidefukushimadaiichi/index-e.html

Treated Water
Portal Site

TEPCO Shorts ALPS
treated water

INSIDE
Fukushima Daiichi

19

Reference ①

20

Reference ②
Explanation Using the ALPS Treated Water Sample Bottle Given during Visits to the Fukushima Daiichi Nuclear Power Station
An article (October 3, 2022) entitled, “’Manipulating impressions’ not possible to avoid criticism” that refers to the explanation given
during visits to the Fukushima Daiichi Nuclear Power Station using a multi-nuclide removal equipment (ALPS) treated water sample
bottle appeared in a newspaper. The main purposes of the explanation that TEPCO gives using an ALPS treated water sample bottle
are as follows and we explain these in detail using a flip board, etc.
[The main purposes of TEPCO’s explanation during visits]-The concentrations of 62 gamma nuclides, such as cesium 137, etc., in ALPS treated water have been reduced below the national
regulatory standard value by purifying and treating with ALPS, etc.
-As a result, the amount of gamma radiation that would have an impact on the human body in the form of external exposure has
been reduced to at least approximately the same level as background radiation (the air dose rate at the measurement location).
-Also, water that has been purified and treated with ALPS, etc., still contains concentrations of unremovable tritium with ALPS, etc.
(beta rays nuclide) that exceed the regulatory concentration limit, and therefore, we will discharge ALPS treated water only after
diluting the water with seawater. (dilution with seawater until the tritium concentration will be below 1/40 of the regulatory
standard).
-The beta radiation emitted by tritium contained in ALPS treated water is so weak that it can be shielded with a single sheet of paper,so the beta rays from the water in the bottle are shielded by the bottle that it is in.
-Therefore, the dosimeter used to measure gamma rays during the explanation cannot measure beta radiation, and even if attempts
were made to measure the beta rays with a dosimeter, it would be impossible to show those radiation measurements in the field.
Furthermore, the air dose rate at the location in which the explanation is given (on site at the power
station) is approximately 0.12µSv per hour, if the concentrations of gamma nuclides such as cesium 137
in the water in the bottle were remained to the level that would result in external exposure(approximately 4,000Bq/L (approximately 44 times the regulatory concentration limit of 90Bq/L) or more,according to our calculation), the needle of the dosimeter used to measure gamma rays would move,
however, there are no such levels of radioactive substances in the water purified and treated with ALPS.
Also using a flip board to show the concentration of cesium 137 before and after purification andtreatment with ALPS, etc., we explain that there are no radioactive substances in ALPS treated water inthe bottle that would result in external exposure, additionally in fact, cesium 137 has been successfully
purified and treated to below the detection limit (value not detected by detailed analysis performed
separately, NOT by measured with the dosimeter at the time of the explanation), which is even lower than
the regulatory concentration limit, thereby deepening the understanding of the characteristic of ALPS
treated water.
Although we deeply regret this news, we will continue to make various efforts to disseminate information
on ALPS treated water and decommissioning in an accurate and easy-to-understand manner.

Visit to the Fukushima Daiichi
Nuclear Power Plant by IAEA
Director-General, H.E. Mr.
Rafael Mariano Grossi (May19, 2022)21