decommissioning at fukushima-daiichi npp · decommissioning at fukushima-daiichi npp ... (october...

All Rights Reserved ©2015 The Tokyo Electric Power Company, Inc.

4 MAR 2014, Fukushima-Daiichi NPP (Source : Nikkei Inc.)

Decommissioning at Fukushima-Daiichi NPP

Takafumi IHARA


All Units maintain cold shutdown �

RPV bottom temp. PCV internal temp.� Fuel pool temp. �

Unit 1 ~17 ~17 ~13

Unit 2 ~21 ~22 ~30

Unit 3 ~20 ~19 ~20

Unit 4 No fuel, so monitoring not required

No fuel, so monitoring not required

~9

Values as of 11:00 on January 11, 2016

1


!  About one-100 thousandth compared with the one after the accident

!  Outside port are substantially below notified concentration.

36 6

36

,

1 ,

0536 -, -

36

- 1-,

36 26

36

26

6

[Regulation limit] Cesium 137: 90 Bq/L Cesium 134: 60 Bq/L

Concentration level of radioactive materials in the sea

" The concentration level has been gradually decreased

15 km off the coast of NPS (Bq/L)

Sea Water Inlet at unit 4 (Bq/L)

Discharge outlet (South) (Bq/L)

Mar 2011 Oct 2015

May 2011

Oct 2015

Apr 2011 Sep 2015


"  TEPCO continuously collects information from all contractors and arrange to assure the necessary number of workers for expected works

Number of workers

3

Average worker in weekday (man/day)��

Month

(May,&2015)&

FY&2013& FY&2014& FY&2015&


Present Status

Water Inventory Issue

Decommissioning Roadmap

Improvement on work environment

Roles and responsibility among organizations for decommissioning

Main Contents

4


Present Status





5


Progress Made at 1F Unit 1

Remote-operated boat and robot identified leakage locations in torus room

Reactor Building (3/15/2011)

Reactor Building Cover (installed in Oct. 2011)

Torus Room (5/27/2014) Torus Room (11/13/2013)

6


Progress Made at 1F Unit 1 (cont’d)

Robot identified leakage from expansion joint of vacuum breaker piping (5/27/2014)

7



Reactor building are being dismantled in preparation for fuel removal

8


(Ref) Procedure of dismantling Unit1 building cover

■Mitigation measures against dust dispersion are being conducted while building cover is dismantled. ■All the roof panels have been dismantled (5 Oct. 2015)

FY 2016 FY 2017 FY 2015 FY 2014

Rubble removal

Installation of fuel handling support etc.

Dismantling building cover

9



Conditions of the top of operating floor Reactor building cover removal

(October 2015)

" Building cover removal is in progress taking measures against dust stirring and of decontamination and shielding on the floor

" Many rubbles on the operating floor will be removed " Finally, the deck and fuel handling machine will be installed

Overview of refueling level (June 2012)


Rubble

Ceiling crane

Picture 1

Picture 2

Picture 3

Surface of fuel spent pool

Cover of reactor well

Ceiling crane

Cover of reactor well




Gamma Camera Image of Refueling Floor (2/21/2013)

Blow-out Panel Closed (3/11/2013)

Steam Coming Out From Blow-out Panel (4/10/2011)

Video images obtained inside primary containment 12



Robot retrieved core samples from refueling

floor (3/21-22/2014) 13



Spent Fuel Pool (2/14~18/2013)

Rubble Removal in Progress (5/29/2013)

Crippled Reactor Building (3/15/2011)

Robot found leakage location in reactor building 14



Rubble in spent fuel pool being removed by remote operation

15


Before large debris removal (March 24, 2011)

N

After removal of large debris

N

(April 19, 2014)

Rubble removal toward fuel removal from SFP in Unit 3 (1/2)

Installation of fuel removal cover and fuel handling facility planned Due to high radiation levels, dose reduction measures must be carried out safely and steadily with remote-controlled heavy machinery.

Current

Status tasks

"  ALARA is kept in the Decontamination and shielding works "  The taget of dose exposure for fuel removal is less than 1mSv/h

16


Decontamination work completed

" The dose rate on the Unit 3 refueling floor is high " Decontamination work is being conducted with remote-

controlled heavy machinery and decontamination devices.

Rubble collection device Suction device

Cutting device

Used for the collection of small debris

Used for suction removal of small debris and dust, etc.

Used for cutting the surfaces of concrete Decontamination work partially

completed

Unit 3 refueling floor

Decontamination toward fuel removal from SFP in Unit 3 (2/2)

17


(Ref) Dose difference between Unit 4 and 3

Measured : ~February 2014

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(Ref) Dose difference between Unit 4 and 3 (cont’d)

19

Unit3 Reactor Building 5F


Current Condition (May 2014)

�

Photo Damage to concrete surface

Photo Condition of north side of R/B

Photos Photo

(Ref) Unit 3 Refueling Floor (Significant Damage Sustained)

20


Preparation Status for Fuel Removal Cover at Unit 3

!  Cover components including steel frame and girder were made and transported to the Onahama Port, more than 50 km away from 1F.

!  Once assembled there in order to confirm working procedure !  Module partially assembled there will be transported to reduce

working hours and occupational dose at site

Removal of Fuel Handling Machine from SFP

(Aug. 2015)

Assembling work at Onahama Port (October 2014)

Fuel removing cover (Image)

Roof Crane

Fuel Handling Machine

Cover for removing fuels


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Concrete wall


Water Injection by Concrete Pumper (3/22/2011)

Fuel Removal from SFP (11/18/2013~)

Spent Fuel Pool Structure Reinforced

(7/30/2011)

S t e e l Pillars

22


On-site transporting cask

Crane

Fuel removal from SFP in Unit 4

��

��

��

On-site transport

Spent fuel pool (SFP)

Fuel removal cover

Cask pit Ensuring

empty space.

Fuel handling machine (FHM)

Cask pit

•  Fuels have been removed since November 18, 2013. •  1533 fuels was stored inside SFP at the time of starting fuel

removal.

Common pool (on site)

23


Fuel removal from SFP in Unit 4 (cont’d)

Status on Sep.22,2011 Removal of PCV head (July 2012)

Construction of cover flame (Jan. ~ May 2013)

Complete the Fuel removal facility cover (Oct. 2013)

Fuel removal work started (Nov. 18. 2013)

Rubble removal on 5th floor of R/B (Mar. 2012)

" Construction period: 11m (From steel flame erection to commence of Fuel Removal)

" Gross weight of newly installed facility: approx. 4,900 ton

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Present Status





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Inflow Approx. 300m3/day

(evaluation value)

Turbine bldg.

Ground water

Contaminated water

Cesium absorption

Mobile strontium removal equipment, etc.

KURION SARRY

From well-points etc. Approx. 100m3/day

Approx. 720m3/day

Sr removal function added

Treated water

Remove 62 radioactive substances except for

tritium

Reactor cooling waterApprox. 320m3/day

, ., 0 539 000 1st Oct.

Sr treated water

Reduced risks

, ., 0 155 000 1st Oct.

RO Concentrated salt water

, .

1st Oct.

Approx. 400m3/dayDesalination

Circulating-Water Core Cooling System at 1F " All Reactor Cores stably cooled " Contaminated water increases daily

Multi-nuclide removal equipment

(ALPS)


3 policies for contaminated water

Site paving

permeable layer Low-permeable layer permeable layer Low-permeable layer

Sub-drain Groundwater level

Sea level

Land-side impermeable wall Land-side impermeable wall

Rain

Trench Sub-drain

Groundwater Bypass Water

Treatment

Sea-side impermeable wall

Policy 1. Remove source of contamination

Policy 2. Isolating groundwater from contamination sources

Policy 3. Preventing leakage of contaminated water

Clean up contaminated water with Multi-nuclide removal equipment (ALPS) Remove contaminated water in trenches (Underground tunnel with piping)

Pumping up groundwater through groundwater bypasses Pumping up groundwater through wells near buildings Installation of frozen-soil impermeable wall on the land side Paving of site to curb permeation of rainwater into soil

Ground improved with water glass Installation of impermeable walls on the sea side Augmentation of tanks (replacement with welded tanks, etc.)

All Rights Reserved ©2015 The Tokyo Electric Power Company, Inc. 28

ISOLATE&WATER&FROM&CONTAMINATION&&

Groundwater Bypass

Pumps collect groundwater flowing

towards the damaged reactor buildings and

divert it safely to the sea

GROUNDWATER&

300-350 Tons/day&pumped&up&&&

50-80 Tons/day&esGmated&amount&of&water&reduced&&flowing&into&reactor&buildings&


Landside Impermeable Wall “Ice Wall”

!  Freezing operation in trial commenced on April 30, 2015 !  70,000 m3 of soil to be frozen !  Freezer plant: 230 kW x 30 units

29

All Rights Reserved ©2015 The Tokyo Electric Power Company, Inc. 30

ISOLATE&WATER&FROM&CONTAMINATION&&

Landside Impermeable Wall “Ice Wall” (cont’d) �

Block groundwater from entering the units and becoming contaminated

1,545 VerGcal&pipes&delivering&soilTfreezing&coolant&

1.5km Long&

PROGRESSION)OF)SOIL)FREEZING)(Begins)March,)2015))


Sub-Drain System

! Operation commenced on September 3, 2015 ! Enable active control of groundwater level around the buildings

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Permeable Layer Low Permeable Layer

Low permeable Layer

Pump-up well

Groundwater level

Permeable Layer

Pump-up Pump-up

Reactor Building

Turbine Building

Sub drain

Isolating water from the contamination source

Sea level

Ice Wall

Groundwater Bypass


Sea-side Impermeable Wall " Sea–side impermeable wall will prevent contaminated water flowing

out to the sea. Almost all facilities are constructed

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Contaminated Water in Underground Trench

The Removal of High-Concentrated Contaminated water in underground trenches has been completed

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3 1 IF FFE D E FE

3 )-‐‑‒3 ( I MFD FE D E I

23 C B FFE D E M

Reactor buildings # �Water treatment facility �

Storage tanks �

F E M ) E

I -‐‑‒DG D C CC

D E NI D C E C DFL C

3 DFLE E F E EE CI

F E MNG II

E

. E I-‐‑‒DG D C M CC FO E F C M CC

Water collecting tanks �

Temporary storage tanks�Water treatment facility for Subdrain & Groundwater drain�

(Ref) Measures against Contaminated Water

" Multiplexing countermeasures based on 3 basic policies

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Present Status





35


Mid- to Long-Term Road Map Towards Decommissioning

Phase-1 Phase-2 Phase-3

Begin removal of fuels from spent fuel

pools

Cold Shutdown Condition Achieved (Dec., 2011)

Within 2 years

Within 10 years

30 to 40 years

Begin removal of fuel debris

Complete decommissioning

Global collaboration vitally important to tackle this unprecedented undertaking

Common pool

Crane F u e l Handling Machine

Unit 4 Nov. 2013

Stop Leakage Flood PCV and Remove Fuel Debris

Today

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Fuel Debris��Submersion

Access ��Top Challenge��Water tightness, Seismic integrity

Partial submersion

��Top �

Partial submersion

��Side �Radioactive dust dispersion,

Radiation shielding

Toward fuel debris removal " Examination of fuel debris retrieval methods in consideration of

water submersion cases


!  Fuel debris from Fukushima site will be analyzed with grove box and manipulator in shielded facilities.

!  In 2013, the terms and conditions for the location of the facility were decided and the operation is scheduled to start in 2018.

②RadioacGve&Material&Analysis&①MockTup&TesGng&

!  Provide such real size equipment as is in NPP to examine the applicability of the remote control equipment and to train operators.

!  Ground breaking ceremony was held on 26 Sep 2014 and the facility started its partial operation in October 2015.

"  To establish technical basis, JAEA will build below with supplementary budget of 2012. Remote-control and Device Development Facility (Mock-up Testing Facility) Radioactive Material Analysis and Research Facility

"  These facilities will be managed in a manner that is easily accessible by domestic and international researchers in various fields.

R&D toward fuel debris removal


Highly pressurized water decontamination device

(Hitachi-GE) Suction and blast decontamination device MHI

Dry ice blast decontamination device (Toshiba)

Investigation Contamination status inside building with robots, leakage points of PCV and status of fuel debris etc. are currently being conducted.

[Main result from investigation] 1.  Water leak was identified at the

reactor of Unit 1 in November, 2013. 2.  M e a s u r i n g w a t e r l e v e l w a s

successfully conducted at the bottom part of RPV in Unit 2 in January, 2014.

1. 2.

R&D toward fuel debris removal Decontamination Robots for lower place on 1st floor of the building have been tested since FY 2013.

Robots have been tested for higher place since FY 2014 and since FY 2015 for upper floor

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Present Status





40


FullTface&respirator&

Surgical&Mask&

Dust&ProtecGve&Mask&

HalfTface&Respirator&

Expanding area without full face mask " Full-face respirator required in all site

areas just after the accident " Currently, full-face respirators are not

required except for works in the buildings and related to contaminated water �

41


Improving welfare facilities

Large resting facility Meal Service Center

"  A large on-site resting area completed in May 2015 for approximately 1,200 workers)

" New office building was completed in October 2014 (for approximately 1200 TEPCO/FDEC employees) " Fukushima Revitalization Meal Service Center commenced to

provide warm lunch to working people onsite in June 2015 Increase of local employment as well as use of local products

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"  The system visualizing the real time dose rate is in place by deploying 20 dose rate detectors on site, increasing to 70 monitors in the future.

"  The display of this system should be placed where workers can easily access.

"  Continuous dust monitoring data will be added to the system in the future.

Visualization of dose rate


■ Debris removal on seaside area ■ Sort out in Tank Area Before After Before After

In front of Unit 2 T/B

Inside of centralized radioactive waste treatment building (RW/B)

In front of Unit 4 T/B

■ Pavement at coastal area Before After

On Sea side area in Units 3 and 4

Improvements on work environment – Field improvement

44


Present Status





45


Establishment of FDEC (Since April 1, 2014)

46


Establishment of FDEC (Since April 1, 2014)

47


Related Organizations for Fukushima decommissioning

Source : Presentation by NDF


Recent Findings

49


Muon Technology for Fuel Debris Identification

http://www.tepco.co.jp/en/nu/fukushima-np/handouts/2015/images/handouts_150319_01-e.pdf

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Expecting result

!  The higher the density is, the more muon are absorbed

!  Permeation method for 2D images, but the use of two detectors makes possible to create 3D images by combining the data

!  The large absorbers in SFP, which were expected to be seen, were verified, but not verified inside the reactor.


3 Phases Investigation B1 : Done B2 : Planned (in FY2015) Pedestal : Planned (2016~2017)

http://www.tepco.co.jp/en/nu/fukushima-np/handouts/2015/images/handouts_150430_04-e.pdf

Shape-Shifting Robots Obtained Crucial Intelligence on Unit1 Inside PCV

51


X-6 Penetration CRD exchanging

rail Entrance to pedestal Personnel

airlock

CRD

Platform

H

W

(Source : TOSHIBA) The other Robot is ready for Probe at Unit 2 Pedestal

CCD Camera ×2 LED

Change

Shape

Boom (enabling angle change)

RPV

52

(Source : TOSHIBA)


Thank you for your attention

[email protected]

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Reference

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Fukushima-Daiichi NPP Map

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decommissioning at fukushima-daiichi npp · decommissioning at fukushima-daiichi npp ... (october...

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