Current Stat Fukushima Daiichi NPS
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FY2014 Technology Research Association International
Decommissioning R&D Institution Symposium
Current Status
on Fukushima Daiichi NPS
July 18, 2014
Naohiro MASUDA
Chief Decommissioning Officer,
Fukushima Daiichi Decontamination and
Decommissioning Engineering Company
Tokyo Electric Power Company
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.
Current Status on Fukushima Daiichi NPS
(Status of Reactors and Buildings)
All units maintain cold shutdown state
Bldg. cover SFP
Opening was closed
Reactor Bldg. 構台 Removed fuel Assemblies
Rubbles
removed 福島第一
福島第一
福島第一
安全第一
安全第一
安全
第一
ｸﾛｰﾗｸﾚｰﾝ
1188/1533
PCV （As of June 90)
Injection Injection Injection
RPV
Fuel debris
福島第一
安全第一
安 全第一
Vent pipes
Torus room
S/C
Unit 1 Unit 2 Unit 3 Unit 4 As of June 27, 2014
100
℃ 100 ℃
Feed water temperature : Feed water temperature : Unit 1
90 Unit 1 90
Temperature : Temperature : Unit 2
80 Unit 2 80
Unit 3
70 Unit 3 70
60 60
50 50
40 40
30 30
20 20
10 10
0 0
3/21 3/31 4/10 4/20 4/30 5/10 5/20 5/30 6/9 6/19 6/29 3/21 3/31 4/10 4/20 4/30 5/10 5/20 5/30 6/9 6/19 6/29
Temperatures of RPV bottom (for three months) Temperatures inside PCV (for three months)
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.
Current Status on Fukushima Daiichi NPS 2
(Status of airborne radioactive materials)
The amount of radioactive materials (cesium) released from Unit 1-3 PCVs is assessed based on
airborne radioactive material concentrations (dust concentration) at the top of Reactor Buildings
→Calculated the assessed value of total release amount (as of July, 2013) as about
10 million Bq/hr.
→About one-80 millionth compared to immediately after the accident.
Accordingly, assessed the exposure dose at site boundary as 0.03 mSv/yr. at maximum.
(Excluding effect of already released radioactive materials) Note: Exposure limit established by law is 1 mSv/yr.
15 The release amount per hour of the radioactive materials (cesium) from Units 1 to 3
10
Approximately one-80 millionth
Release Rate (Bq/hr)
13
compared to at the time of accident
10
11
10 about 10 million Bq/hour
(about 1×107 Bq/hour)
9
10
3/15 3/25 4/4 6/20 7/26 9/1 10/3 11/1 11/26 12/28 2/1 2/24 3/27 May July Sept. Nov. Jan. Mar. May July
- 3/26 - 4/6 - 6/28 - 8/12 - 9/17 - 10/13 - 11/10 - 12/6 - 1/13 - 2/13 - 3/7 - 4/15
2011 2012 2013
Radioactive particle (Cesium) release per hour from Units 1 to 3
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.
Current Status on Fukushima Daiichi NPS (Status of monitoring port area) 3
Concentration of radioactive materials has been reduced up to one-100,000th to one-1,000,000th as
compared to the time right after the accident. （ Bq/L） 物揚場前
North side5,6号 機放 水口北 側 5 and 6 10000000
（Bq /L ） of water outlets at Units Front～of
シ ル トフ ェン ス 設 置：4/11 cargo
4/14 unloading wharf
1 00 000 00 I-131
1000000 Installation of silt fence: April 11 to April 14 Cs-134
I-1 31
10 000 00 Cs-1 34 Cs-137
Cs-1 37 100000
1 000 00
10000
100 00
1000
10 00
100
1 00
10
10
1
11/11/15
13/1/8
13/3/9
11/3/20
11/5/19
11/7/18
11/9/16
12/1/14
12/3/14
12/5/13
12/7/12
12/9/10
12/11/9
13/5/8
13/7/7
13/9/5
13/11/4
14/1/3
14/3/4
14/5/3
14/7/2
1
13/1/8
11/3/20
11/5/19
11/7/18
11/9/16
11/11/15
12/1/14
12/5/13
12/7/12
12/9/10
12/11/9
13/3/9
13/5/8
13/7/7
13/9/5
13/11/4
14/1/3
14/3/4
14/5/3
14/7/2
12/3/14
（Bq/L） 南放水口付
Vicinity of south side of近water outlet
10000000
I-131
Notified concentrations 1000000 Cs-134
Cs-137
(Concentration limits for water outside
environmental monitoring area) 100000
・Cesium 137: 90 Bq/L
10000
・Cesium 134: 60 Bq/L
1000
100
10
1
13/1/8
11/3/20
11/5/19
11/7/18
11/9/16
11/11/15
12/1/14
12/5/13
12/7/12
12/9/10
12/11/9
13/3/9
13/5/8
13/7/7
13/9/5
13/11/4
14/1/3
14/3/4
14/5/3
14/7/2
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc. 12/3/14
Current Status on Fukushima Daiichi NPS (Plant stabilization) 4
Hydrogen concentration has been kept below inflammability limit by nitrogen injection
into PCV and RPV to prevent hydrogen explosion.
Gas is extracted from PCV and filtered, radioactive materials released into
environment are reduced.
Concentration and amount of radioactive materials released into atmosphere are
monitored.
Subcritical state is also monitored by monitoring radioactive concentration of short-
lifetime nuclides (Xe-133, Xe-135).
Release
Primary containment vessel (PCV)
gas control system
Nitrogen Supply HEPA
Unit filter Air extraction fan
Monitor of inert gas
and hydrogen
Nitrogen injection and gas control system (Unit 1)
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.
Current Status on Fukushima Daiichi NPS (Cooling of SFPs) 5
To continuously remove decay heat generated from fuel in
SFP, water in SFP is cooled by using both existing facilities
and newly installed facilities.
Chlorine concentration was decreased by mobile reverse
osmosis (RO) no later than March 18, 2013. It is regularly
monitored to be less than 100 ppm.
R/B
SFP circulate water cooling system in Unit 4
Skimmer surge tank
RW/B FSTR/B* Outside
Emergency water
Circulated water
injection line
cooling system
SFP
Spent fuel Hx unit
Cooling tower
Ｈｘ
FPC Hx Primary
Secondary
system
system
：Existing line
：Temporary line of primary system
：Temporary line of secondary system Primary pump Secondary
サージ
：Connected line injected from outside タンク
pump
Water supply line for
*Cooling tower supply water, water skimmer surge tank
injection of skimmer surge tank, * Filter sludge
emergency water injection, etc. Water supply line for
tank room
cooling tower
building
SFP alternate circulate water cooling system (Unit2)
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.
Current Status on Fukushima Daiichi NPS (Reactor cooling) 6
Plants
Plants have
have been
been stabilized
stabilized with
with sufficiently
sufficiently low
low temperature
temperature byby continuous
continuous circulation
circulation water
water cooling.
cooling.
Plant
Plant conditions
conditions have
have been
been monitored
monitored atat seismic
seismic isolated
isolated building
building on
on aa 24-hour
24-hour basis.
basis.
Primary 100000000
Reactor building containment vessel 10000000
Cs-134
concentration
1000000
Spent fuel pool
放射能濃度［Bq/㍑］
Reactor pressure
100000
Cs-137
[Bq/liter]
10000 100000000
vessel 全β beta
Radioactive concentration
1000
Radioactive
Gross 10000000
Inflow of 100 1000000
放射能濃度［Bq/㍑］
Turbine 10 H-3 100000
ground water
[Bq/liter]
1
building 10000
~400m3/day 0.1
建屋滞留水
Accumul
ated1
1000
100
water
inside Cesium 10
building
removal 1
0.1
セシウム除去
建Outlet water
装置出口水 2
of cesium
removal unit
Groundwater Contaminated water
Reactor cooling water Cooling by recirculating cooling water
Approx. 320m3/day Approx. 720
Temporary storage
Desalination facility
Cooling ・ Reserve m3/day Waste sludge
water osmosis
Waste absorbent, etc.
membrane
Reactor water injection pump tank ・ Evaporative Treated water
concentration (contaminated water)
Cooling 100000000
種の放射能濃度 Approx. 400 m3/day
water 10000000
concentration
Radioactive concentration
tank 1000000
放射能濃度［Bq/㍑］
100000
[Bq/liter]
10000
[Bq/liter]
Radioactive
1000
100
Fresh
10
water 1
0.1 Outlet water of Advanced Liquid
Back-up equipment 淡水化処理装置
3 unit
desalination
出口水（淡水） Storage tanks Storage tanks Outlet water of
ALPS
(Fresh water)
Processing System (ALPS)
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.
Current Status of Fukushima Daiichi NPS (Contaminated water storage) 7
Status on contaminated water storage
Tonal
Tonal amount
amount of 490,000m33 ** is
of 490,000m is stored
stored in
in tanks.
tanks.
Current
Current available
available storage capacity** is
storage capacity 520,000m33..
is 520,000m
Available
Available storage
storage capacity
capacity will
will be
be increased
increased up
up to 800,000m33.. (by
to 800,000m (by the
the end
end of
of March
March 2015
2015 ))
【Amount of contaminated water stored in tanks＊】
Fresh water： approx. 24,000m3
Waste water generated by evaporative concentration：
approx. 9,000m3
Concentrated salt water at RO device：
approx. 366,000m3
Steel square type tank Water treated by ALPS： approx. 92,000m3
【 Available amount of storage tank＊】
Steel square type tank：
approx. 3,000m3
(Accumulated water in Units 5 and 6, concentrated salt water at RO
device)
Welded type steel
cylindrical tank Flange type steel cylindrical tank：
Flange type steel approx. 291,000m3
cylindrical tank (Fresh water, concentrated salt water at RO device, water treated by
ALPS)
Welded type steel cylindrical tank：
approx. 174,000m3
(Concentrated salt water at RO device, water treated by ALPS)
Steel horizontal tank：
approx. 38,000m3
(Concentrated salt water, waste water generated by evaporative
Steel horizontal tank
concentration)
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc. *As of June 17, 2014
Measures against contaminated water 8
Sub-drain
4>
Groundwater bypass Approx.
Approx. 800 800 m
33
m /day
/day of
of groundwater
groundwater flows
flows into
into the
the site
site from
from the
the mountain
mountain
side.
side. ItIt is
is assumed
assumed thatthat approx.
approx. 400 m33/day
400 m /day out
out of 800m33/day
of 800m /day flows
flows into
into
33
Ocean-side the
the buildings
buildings andand the
the remaining
remaining (approx.
(approx. 400
400 mm /day)
/day) flows
flows into
into the
the sea.
sea.
Impermeable AsAs the
the groundwater
groundwater flowing
flowing into
into the
the buildings
buildings becomes
becomes contaminated,
contaminated, itit
walls needs
needs processing.
processing.
Ground improvement
Three basic principles of measures against
contaminated water
1. Removal of contamination source ●
Land-side 2. Isolation of water from contamination source ○
frozen-soil 3. Leakage Prevention of contaminated water ◆
impermeable
walls
Emergency measures Fundamental measures
1. Removal of highly 4. Pumping up groundwater
Drainage by sub-drain ○
channel
contaminated water from
trenches ● 5. Installation of ocean-side
2. Ground improvement at impermeable walls ◆
contaminated area with water ＋ 6. Installation of land-side
frozen-soil impermeable walls
glass, pavement of ground
surface with asphalt, etc. and ○
pumping up groundwater ○◆ 7. Installation of contaminated
3. Pumping up groundwater water processing facilities
from the mountain side with higher performance ●
(Groundwater bypass) ○ etc.
＋
Main preventive measures
(1)
Additional measures taken against inflow of groundwater (consideration of facing) ○
, etc.
Provided by Japan Space Imaging Corporation, (C)Digital Globe
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.
Measures against contaminated water – Emergency measures – 9
Groundwater pump up
(Groundwater bypass) Emergency measure (1)
Pump-up Eliminate highly
contaminated water in
Water level trenches. [Removal]
Reactor Turbine
Building Building
Pump-up
Permea
ble
Low perm Laye Trench Sea level
eable La r
Permea yer
ble Laye
r
Low Per Pump-up well
meable
Layer
Sub drain Sub drain
Isolation of water from the Groundwater
contamination source drain pump-up
Emergency measure (3) Emergency measure(2) Improve ground at the
Pump up groundwater contaminated area with water glass, pave the
from the mountain side ground surface with asphalt and pump up
(groundwater bypass) groundwater. [Isolation], [Leakage prevention]
[Isolation]
Improve
Improve ground
ground and
and pump
pump upup groundwater
groundwater
• April 9,2014, pumping up
Pave
Pave ground
ground surface
surface with
with asphalt
asphalt to
to curb
curb rainwater
rainwater
ground water at the wells
infiltration
infiltration
was started.
Pump-up well
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Measures against contaminated water – Fundamental measures – 10
Fundamental Measure(4) Pump up
groundwater by sub-drains. [Isolation]
Water level
Reactor Turbine
Pump-up Building Pump-up
Building
Permea Sea level
ble Layer
Low perm
eable La
Permea yer
ble Laye Pump-up well
Low Per r
meable
Layer Sub drain Sub drain
Isolating water from the Groundwater drain
contamination source pump-up
Fundamental Measure (6) Install the land-side Fundamental Measure (5) Install the ocean-side
frozen-soil impermeable walls on the mountain side impermeable walls. [Leakage prevention]
to curb increase contaminated water generated by
groundwater flowing into buildings. [Isolation]
Freezing
Freezing began
began in
in March,
March, 2015.
2015. [Supported
[Supported by
by METI]
METI]
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Measures against contaminated water 11
Groundwater bypass
Unit: ton Removal of highly contaminated water from trench
Discharged
Date Facility overview
amount
Already
blocked
1 May, 21 561 ton
Turbine building3
Pit B Pit C
Pit B
2 May, 27 641 ton Tunnel B Pit C Tunnel B
nel C
lA
lC
Unit-3
Pit
Unit-2
Tunne
Tunnel A
nne
seawater Cable
3 Jun, 2 833 ton seawater
Tun
tray
piping
Tu
piping trench trench
Piping Tunnel
4 Jun, 8 1,563 ton Pit D
Pit A
Pit A Pit D
5 Jun, 14 1,443 ton Unit-2 turbine Unit-3 turbine
Example of freezing model test condition
building building
6 Jun, 20 1,765 ton
Excavated duct
7 Jun, 26 1,829 ton
8 Jul, 2 1,858 ton Ground-freezing water-shutoff location Packer
Location to be used freezing plant, etc.
Internal block location
9 Jul, 8 1,725ton
Groundwater will be pumped up from the mountain side and discharged into Right after the accident, contaminated water flew out to the ocean from
the ocean (Groundwater bypass). It is expected that the amount of inflow
into the buildings is to be reduced by tens to 100 tons of water at maximum. the seawater inlet through trenches, etc.
The water pumped up from pump-up wells is temporarily stored in tanks to Outflow locations were sealed. However, the contaminated water
measure the radioactivity. It is ensured that the values are less than the
target values prior to discharge. stayed in the underground structures should be extracted, and the
structure should be blocked.
Unit 1 to 3 CST
Shortening of Treatment of the water stayed in trench has been conducted with
circulating cooling mobile processing units (Commencing on Nov. 14, 2013 at Unit 2; on
Nov. 15, 2013 at Unit 3)
water line New RO SPT Freezing and water removal are prepared/underway. (Unit 2: Starting
freezing on Apr. 2, 2014. It was expected that freezing would be
SARRY
Approx. 3 km completed in June 2014, but freezing is not going on as planned.
Freezing is still continuing. Unit 3: Planned to complete freezing in Aug.
2014)
Shortening By installing a new RO system inside the Unit 4 turbine building, the length of
of line the circulating cooling water line for the reactor will be shortened to approx.
0.8 km from current 3 km by the end of March, 2015 in order to reduce the risk
Approx. 0.8 km of leakage and avoid radiation dose of workers.
Storage tanks
(RO treated/condensed water)
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Measures against contaminated water 12
(Improvement on processing efficiency of ALPS)
● For more efficient contaminated water processing
(ALPS with high-performance by government support)
Current
Current ALPS
ALPS has
has three
three trains.
trains. These
These trains
trains are
are currently
currently in
in operation.
operation.
Additional
Additional ALPS
ALPS will
will also
also have
have three
three trains.
trains. Operation
Operation commencement
commencement is is planned
planned inin the
the middle
middle of
of FY2014.
FY2014.
High-performance
High-performance ALPS
ALPS willwill have
have one
one system.
system. Operation
Operation commencement
commencement is is also
also planned
planned inin the
the middle
middle of
of FY2014.
FY2014.
Current ALPS Additional ALPS High-performance ALPS*
Processed amount 750 m3/day 750 m3/day 500 m3/day or more
3 trains 3 trains
Number of trains 1 train
(250 m3/train) (250 m3/train)
Target nuclides to Concentration limit by law or less for 62 out of all 63 nuclides
remove (except for tritium).
Waste generation 1/20th compared with
－ －
amount existing ALPS
Operation
March 2014 Middle of FY 2014 Middle of FY 2014
commencement
* Conducted as a project with expense support form Government of Japan.
* Implemented to greatly reduce the amount of secondary waste generated as deposit after water processing
(80% or more) and to improve the processing performance.
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Measures against contaminated water 13
(Status on response to ALPS trouble)
■ Configuration of existing ALPS
Deposition
Deposition
To HIC processing
for slurry products To HIC
processing Filters whose parts have undergone radiation degradation
products
for slurry and leakage
Cross-flow
Filter 1 To HIC for
Booster adsorbents
Circulation
Batch P pump 2 Processing
tank
processing
Circulation P
column
tank 1 pump 1 Supply 3) ALPS
tank Cross-flow
P filter 2
Slurry P P
transport To the tanks/
Slurry pump Supply Circulation reservoirs
pump 2 pump 2
Supernatant
P P Adsorption Adsorption P
tower einlet tower
Decant Supply Buffer tank Outlet Transport Transpor
Batch Decant Coprecipitation t
pump pump 1 Filter tank
processing tank tank pump
tank 2 P
Booster
1) Pre-processing facilities pump 1 Spent
Chemical 2) Pre-processing facilities Adsorbent
supply
(Iron coprecipitation
processing) facilities (Carbonate deposition To HIC for
(shared) processing) adsorbents
Sampling
Additional sampling (Ca concentration) (radioactive concentration)
Ca concentration at outlet of booster pump 1 Water radioactive concentration at train outlet (Gross beta level)
Sampling Sampling Ca Sampling Radioactive concentration
Sampling location
train date concentration date (Gross beta level)
train-A 3/27 11 pm train B outlet water 3/18 103 to 104 Bq/cc
train-A 5/17 11 ppm train-A outlet water 5/17 2.4×10-1 Bq/cc
train-C 5/20 6.2 ppm train-C outlet water 5/19 4.0×10-1 Bq/cc
In train-B, filter components have degraded due to radiation, causing contamination to moving downstream. The parts were replaced with
those higher resistant against radiation, and operation of train B restarted on May 23.
In trains A and C, measures are taken to allow earlier detection on contaminant (additional sampling) to prevent them from moving
downstream.
Operation of train A was also restarted on June 9 after the filter were replaced with another one. Operation of train C was restarted on June
22 after taking same measures.
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Major work steps for decommissioning and current status of respective Unit 14
The
The major
major work
work items
items forfor decommissioning
decommissioning include
include fuel
fuel removal
removal from
from SFP,
SFP, fuel
fuel debris
debris
removal
removal (molten
(molten fuel),
fuel), dismantling
dismantling plant
plant etc.
etc.
Currently
Currently removing
removing fuels
fuels from
from Unit
Unit 44 SFP
SFP and
and simultaneously
simultaneously preparing
preparing for
for starting
starting
fuel
fuel debris
debris removal
removal inin Units
Units 11 to
to 3.
3.
Units 1 to 2 Unit 3 Unit 4
Fuel removal from Rubble Installation of
Storage/Trans
SFP removal, fuel removal Fuel removal
port
clean-up facility
Units 1 to 3
Clean-up,
Fuel debris removal Investigation Water sealing, Fuel debris Storage/Trans
(molten fuel) of leak filling water removal port
location
Developing Designing and
Dismantling
Dismantling plant etc. scenario and manufacturing
etc.
technology equipment
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Current Status of Unit 1 15
Current Status
•Building cover installed (November, 2011)
•Sustained stable reactor cooling, which has reduced the generated amount of radioactive
materials
Tasks
•Removal of the building cover
•Identification of the status of debris on the defueling floor and inside the pools
•Countermeasures for the dispersion of radioactive materials during the removal of the
building cover
•Shortening the period of the time of removing the building cover
As of Mar. 12, 2011 Completion of building cover structure
Present
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Toward fuel debris removal (Preparation for fuel debris removal) 16
Investigation under vent pipes in Unit 1 (Overview)
To
To repair
repair (seal
(seal the
the water
water leak
leak locations
locations of)
of) the
the PCV
PCV inin preparation
preparation for
for thethe fuel
fuel debris
debris removal,
removal, investigation
investigation under
under
vent
vent pipes
pipes was
was conducted
conducted toto identify
identify the
the leak
leak locations
locations inin the
the PCV.
PCV.
With
With the
the images
images taken
taken by
by the
the camera
camera equipped
equipped withwith the
the water
water boat,
boat, itit was
was checked
checked whether
whether there
there is
is any
any water
water flow
flow
from
from the
the sleeve
sleeve ends
ends of
of vent
vent pipes
pipes oror not,
not, and
and the
the status
status ofof the
the sand
sand cushion
cushion drain
drain pipes
pipes was
was also
also checked
checked (by
(by
viewing
viewing appearance).
appearance).
PCV
Vacuum break line
SR
Ven
valv
e ex S/C
t pi p ha u
s l ee
ve
e st p
ipe Vent pipe
A B
Sand cushio
n C
drain pipe
Sand
cushion D
Location Ａ: Vent pipe sleeve
Location B: Vent pipe
Location C: Sand cushion drain
pipe サンドクッション
Location D: Sand cushion ring
header ドレンライン
Drain funnel
Suppression chamber (S/C)
Water boat
Water boat: trial operation at the plant
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Finding of leakage at the Unit 1 17
By
By deploying
deploying aa remote
remote controlled
controlled robot
robot on
on the
the cat
cat walks
walks in
in the
the torus
torus room
room inin the
the Unit
Unit 11
from
from May
May 27,
27, aa leak
leak from
from the
the protective
protective cover
cover ofof aa expansion
expansion joint
joint on
on vacuum
vacuum break
break
line
line was
was identified.
identified.
The
The investigation
investigation results
results will
will be
be reflected
reflected into
into the
the planning
planning for
for further
further investigation
investigation and
and
sealing
sealing the
the water
water leak
leak location
location of
of the
the PCV
PCV forfor filling
filling the
the PCV
PCV with
with water
water in
in the
the future.
future.
SHC system
e Protective cover for
n e
eak li sid
r V
Camera m
b PC expansion joint
c uu Leak
AC Torus hatch Va
expansion
joint
Vacuum
break valve
Vacuum break valve
Cat walks
Robot “Hitachi Tele Runner”
Image of investigation on upper part of suppression chamber
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Current Status of Unit 2 18
Current Status
•Very high radiation level in the building
Inspection of contamination status on the defueling floor will be conducted in the future.
Tasks
•Radiation dose reduction measures
•Countermeasures for the dispersion of radioactive materials during engineering work
Opened blowout panel
As of Apr. 10, 2011 Present
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Toward fuel debris removal (Preparation for fuel debris removal) 19
Measurement of water level in S/C in Unit 2 (Overview)
To
To repair
repair (seal
(seal the
the water
water leak
leak locations
locations of)
of) the
the PCV
PCV in
in preparation
preparation for
for the
the fuel
fuel debris
debris removal,
removal, the
the water
water level
level in
in the
the
S/C
S/C was
was measured
measured to to assume
assume the the state
state of
of the
the opening
opening area
area at
at leak
leak locations
locations in in the
the PCV.
PCV.
(By
(By checking
checking the the water
water level
level difference
difference between
between thethe inside
inside and
and outside
outside ofof the
the S/C,
S/C, the
the opening
opening area
area was
was assumed,
assumed,
and
and itit will
will be
be considered
considered thatthat itit is
is possible
possible whether
whether the
the water
water sealing
sealing material
material might
might flow
flow out
out of
of the
the S/C
S/C or
or not.)
not.)
Water level Ascending/descending unit
measurement device Winch unit
Transfer unit
Status of installation of device on Appearance of measurement
S/C outer surface device-hanging/retrieving device
Outer surface on S/C
Device-hanging/retrieving device
装置吊り
Torus room
トーラス室 下ろし・回
Water level
S/C
Ｓ／Ｃ 収装置 measurement
Water level
measurement device device
Ｓ／Ｃ内 Water level
Moving
difference
水位測定between the
装置
inside and outside
of S/C:
Approx. 30 cm
Accumulated water surface
in torus room
Overview on water level measurement in S/C at Unit 2 Measurement by device
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Toward fuel debris removal (Preparation for fuel debris removal) 20
PCV (inside of pedestal) investigation in Unit 2 (Provisional plan)
Investigation
Investigation is
is planned
planned by
by putting
putting the
the investigation
investigation device
device into
into pedestal
pedestal via
via X-6
X-6
penetration,
penetration, CRD
CRD exchanging
exchanging rail
rail and
and opening
opening ofof pedestal
pedestal so
so that
that location
location (distribution)
(distribution)
of
of fuel
fuel debris
debris in
in pedestal
pedestal can
can be
be identified.
identified.
Status
Status was
was checked
checked from
from CRD
CRD exchanging
exchanging rail
rail to
to opening
opening of
of pedestal
pedestal as
as preliminary
preliminary
investigation.
investigation.
Investigation ＰＣＶ
Both for identifying the access route inside the pedestal RPV
and for understanding the status and circumstantial
condition inside the PCV
Investigation on the status of
CRD exchanging rail and CRD
opening of pedestal
Investigation conducted from X-
53 penetration in August, 2013
Platform
X-6
Penetration CRD exchanging rail
Opening of
pedestal Personnel airlock
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Toward fuel debris removal (Preparation for fuel debris removal) 21
PCV (inside of pedestal) investigation In Unit 2 (Investigation results)
① ② 1F Grating
1F Grating
f rail
eo
n toward l
Edg ht of
Directio g
ail
o f pedest
a hei m
exch of CRD
in g
ng r
en
op
30m
Deposit
angi
CRD CRD
e
exchanging exchanging
Edg
rail face rail face
Image location and direction RPV
X-53
PCV ③
Opening of pedestal
X-6
①
②
③ Pedestal
1F Grating
CRD exchanging rail
Perimeter of opening of pedestal
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Finding of water levels inside unit 2 Pressure Containment Vessel 22
After
After failing
failing to
to insert
insert aa measurement
measurement instrument
instrument in
in March
March 2012,
2012, re-inserting
re-inserting of
of an
an
instrument
instrument waswas successful
successful in
in early
early June
June 2014.
2014.
Water
Water levels
levels and
and temperatures
temperatures inside
inside PCV
PCV have
have since
since been
been monitored.
monitored.
［As of 8:00, June 11, 2014］
：Thermometer
：Water gauge Monitoring results
Height
X-53 Temp.[℃] Water level
X-53
TE08 OP12,460
TE08 33.7 － － OP.11,920
The water level seems to be
around over flow height into
TE07 the vent pipe TE07 33.7 － － OP.10,690
TE06 33.5 － － OP.8,100
PC
Grating OP 9,510
V
TE05 33.5 LE05 OFF OP.6,430
sh
ell
TE06 pe TE04 33.5 LE04 OFF OP.6,230
t pi 344 mm
ven (design value)
TE03 33.6 LE03 OFF OP.6,030
TE05 LE05
TE04 LE04 OP.5,830
TE03 LE03 TE02 35.0 LE02 OFF *350 mm from the bottom of
TE02 LE02 Bottom of PCV PCV
Water depth : TE01 LE01 Ref: around a vent pipe OP.5,630
TE01 35.8 LE01 ON * 350 mm from the bottom
300 mm of PCV
Bottom of PCV OP 5,480
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Current Status of Unit 3 23
Current Status
•Debris removal from the top of the reactor building completed (October 11, 2013)
•Installation of fuel removal cover and fuel handling facility planned
•Steel frame debris dropped into SFP (September, 2012)
•Beginning target of fuel removal activities rescheduled from the perspective of getting safety most prioritized
(Changed from the end of December, 2014 to the end of September, 2015)
Tasks
•Due to high radiation levels, radiation dose reduction measures must be conducted safely and steadily with
remote-controlled heavy machinery.
Damaged by Completion of
hydrogen explosion debris removal
Present
As of Feb. 12, 2012 As of Oct. 11, 2013
Fuel handling machine
Measures
against
rainwater Crane
(protection
against
rainwater)
North
Fuel removal
Image of Fuel removal cover
cover structure
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Toward fuel debris removal (Fuel removal from SFP) 24
With remotely operated heavy machinery, the removing activity of debris from the top floor
completed (October 11, 2013)
Fuel removal from spent fuel pool continuously conducted
Currently developing/implementing the plan for decontamination and shielding against radiation
N
Photo taken on March 24, 2011
Before large debris removal
N
Photo taken on April 19, 2014
After removal of large debris
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Toward fuel debris removal (Preparation for fuel debris removal) 25
Water flow from area near MSIV room to floor drain funnel on 1st floor in R/B
at Unit 3
On January 18, 2014, checking the camera images from the debris removal robot (ASTACO-SoRa) in unit 3, our personnel found that
water flowing from the area near the door of the main steam isolation valve (MSIV) room toward the floor drain funnel in the vicinity in
the north-eastern area on the 1st floor at Unit 3 R/B.
On January 21, 2014, it was identified that water injection amount was greatly reduced while the robot was operated for debris
removal work.
No change on plant parameter, etc has been found.
North
Floor drain
funnel
Water flow
(RF-123B)
Floor drain funnel
Water flow confirmed (on Jan. 18)
MSIV
room
Remote-controlled
heavy machinery
(ASTACO-SoRa)
Water flow reduction confirmed
Floor map of 1st floor in R/B at Unit 3 (on Jan. 21)
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Finding of leakage at the Unit 3 26
On May 15, by inserting a camera into the Main Steam Isolation Valve (MSIV) room, a leak from
around a Main Steam (MS) line was identified. It was the first confirmation of a leak from the Unit 3
PCV.
Expansion joint Ｃ
構台
福島第一
福島第一
福島第一安全第一
安全第一
安
Pan-tilt camera Endoscope camera
Expansion joint Ｄ
全
第
一
Endoscope camera
Water flow
injection Pan-tilt camera R/B 2nd floor
Dose monitor HVAC room
安全第一
福島第一
Penetration on
PCV by MS pipes MS process
radiation
R/B 1st floor monitor
Backup penetration（X-46,47） MSIV room
O.P.15280
PCV side
Feed water penetration（X-9A,B） Feed water pipes
O.P.13270
Level of water inside Ａ Ｂ
PCV
(estimated by water head) grating
O.P.12020～12090 Ａ Ｂ Ｃ Ｄ
O.P.11670 MS pipes
MS penetration（X-A to D）
O.P.10610
MS drain penetration（X-8）
Penetration on PCV in MSIV room Cross section of MSIV room
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Current Status of Unit 4 27
Current Status
•Fuel removal from SFP commenced (November 18, 2013, target by the end of year 2014)
Tasks
•Continuing work while ensuring safety
•Exploring the methodology for the removal of the fuels with their leaks confirmed
As of Sep. 22, 2011 Fuel Removal Cover Structure
Present
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Toward fuel debris removal (Fuel removal from SFPs) 28
Defueling cover
Work environment Fuels have been removed from Spent Fuel Pool (SFP) in Unit 4 since
Fuel arrangement area (within dot
Crane
line) November 18, 2013.
handling
facility Fuel handling Spent fuel pool (SFP) 1533 fuels was stored inside SFP at the time of starting fuel removal.
machine (FHM) Fuel assembly They are scheduled to be completely removed by the end of year
Spent fuel storage rack 2014.
1188 fuels have been already removed and transported to common
On-site fuel pool on site as of June 30, 2014.
transporting cask
キャスク キャスク
ピット ピット
Cask pit
貯蔵エリア
Storage area Cask pit
Ensuring
Fuel removal 空きスペース
empty
の確保
space.
Common pool on site
On-site transportImprovement on work environment 29
Workers：approximately 5,000 persons per day (As of June, 2014)
◇ Efforts to reduce the area where full-face mask should be worn and to reduce radiation dose for site workers
◇ Welfare facilities
Mobile rest facility by modifying large bus (operated since January, 2014)
Large rest facility (with 8 story building, can accommodate approx. 1200 persons, will be operated by the end
of December, 2014.)
Cafeteria (will be constructed in Okuma-town by the end of March, 2015, can supply 3000 meals)
◇ improvement on environment of work place
Temporary administrative building (can accommodate 1,000 TEPCO employees, operated in order from July,
2014)
Permanent administrative building (will accommodate TEPCO employees plus contractors, will be
constructed by the end of March, 2016)
Damaged vehicles at the sea side of T/B with high radiation have been removed as rubbles.
Area reduction where full-face mask should be worn Removal of damaged vehicle rubbles
Conventional area Two thirds （Before ） （After ）
Additional area or more of
Daiichi site
Tank area
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Promotion of decommissioning works at Fukushima Daiichi NPS 30
Fukushima
Fukushima Daiichi
Daiichi Decontamination
Decontamination and
and Decommissioning
Decommissioning Engineering
Engineering Company
Company
(FDEC)
(FDEC) was
was established
established to
to control
control the
the entire
entire decommissioning-related
decommissioning-related divisions.
divisions.
Decommissioning
Decommissioning and
and measures
measures against
against contaminated
contaminated water
water issue
issue will
will be
be expedited
expedited as
as aa
Japanese
Japanese government
government project
project by
by collecting
collecting the
the wisdom
wisdom from
from experts
experts inside
inside and
and outside
outside of
of
Japan.
Japan.
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Expectation to IRID (1/2) 31
To
To go
go ahead
ahead with
with Fukushima
Fukushima Daiichi
Daiichi decommissioning
decommissioning works works safely
safely andand steadily,
steadily, R&D
R&D
is
is essential,
essential, such
such as
as development
development of of remote-controlled
remote-controlled device
device etc.
etc.
As
As for
for decontamination
decontamination device
device and
and device
device for
for identifying
identifying PCV
PCV leakleak locations
locations with
with
remote
remote control,
control, desired
desired results
results are
are gradually
gradually being
being obtained
obtained with
with verification
verification testing.
testing.
R&D
R&D isis imperative
imperative for
for water
water sealing
sealing in
in S/C,
S/C, inside
inside investigation,
investigation, filling
filling water,
water, fuel
fuel debris
debris
removal
removal inin PCV
PCV to
to achieve
achieve fuel
fuel debris
debris removal
removal in
in the
the future.
future.
Units 1 to 2 Unit 3 Unit 4
Fuel removal from Rubble Installation of
Storage/Trans
SFP removal, fuel removal Fuel removal
port
clean-up facility
Units 1 to 3
Clean-up,
Fuel debris removal Investigation Water sealing, Fuel debris Storage/Trans
(molten fuel) of leak filling water removal port
location
Developing Designing and
Dismantling
Dismantling plant etc. scenario and manufacturing
etc.
technology equipment
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.Expectation to IRID (2/2) 32
Collecting knowledge and experience inside and outside of Japan
based on needs and challenges in terms of decommissioning of
Fukushima Daiichi nuclear power station, screening and giving an
expert opinion on technologies
Collecting prospective technologies in request for proposals of alternative
fuel debris removal
Developing element technologies with an eye on using flexibly in the future
decommissioning work
Developing technologies and equipment in considering the reality of
the situation and the time frame requirement
The element technologies closely relevant to the site can be applied to the
site, such as the suction and blast decontamination equipment used inside
buildings
Through close information exchange and cooperation with IRID,
Fukushima Daiichi D&D company strive to resolve the challenges faced
at the site
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.For more information 33
Updated information regarding decommissioning is shared on TEPCO website.
http://www.tepco.co.jp/en/decommision/index-e.html
Click
All Rights Reserved ©2014 The Tokyo Electric Power Company, Inc.You can also read
