Introduction to Genkai Nuclear Power Station
Introduction
OutlineofGenkai
Power
Statio
System
InsidethePower
Station
Securing
Safety
Serious
incident
countermeasures
DecommissioningplanMonitoring
Waste
Treatment
Community
ActivitiesAGuidetothe
Surrounding
Region
Compared with oil and other energy sources, nuclear power offers numerous advantages, including a stable supply of
resources, harmony with the environment, and superior economy.
Genkai Nuclear Power Station began commercial operation in October 1975 with the startup of the No. 1 Unit. Since then,
we have constructed three additional units to meet the growing demand for electric energy. As a result of those expansions,
Genkai’s output rose to 3,478 megawatts.
The No. 1 and No. 2 units subsequently ceased operation on April 27, 2015, and April 9, 2019, respectively, bringing the
current total output to 2,360 megawatts.
All of Genkai’s employees will continue to work together to accomplish the planned decommissioning of the No. 1 and No.
2 Units as well as the safe, stable operation of the No. 3 and No. 4 Units while ensuring that safety remains the top priority.
A characteristic of carbon dioxide and other greenhouse effect gases is that they absorb infrared rays and other sources of
heat while letting visible light through. If the amount of greenhouse gases rises, it is believed that heat will be trapped inside
the atmosphere and lead to global warming.
Ensuring a stable supply of electricity
The mechanism for global warming
Infrared rays
Earth
Atmosphere
The naturally occurring greenhouse effect If the amount of greenhouse effect gases increases
Infrared rays Sunlight
Sunlight
Earth
Atmosphere
■しかくBalanced Diversification of Power Sources
Kyushu Electric Power strives to combine a variety of power sources in order to deliver an optimal mix based on
considerations including stability of fuel procurement, generating cost, and environmental impact. A typical mix during
peak power demand in the summer would be nuclear and coal-fired generation for baseload, LNG-fired generation for
middle load, and oil-fired generation for peak load. We’re also maximizing use of solar and wind as we accommodate
power demand.
Japan is a resource-poor country with an
energy self-sufficiency rate of just 8%.
Because we depend on imports for most
energy resources in a process that is highly
susceptible to global conditions, ensuring
energy security is a top priority. Additionally,
the need to reduce emissions of greenhouse
gases such as carbon dioxide in order to deal
with global warming remains a pressing and
enduring issue.
Consequently, it is necessary to combine
nuclear, thermal, and renewable energy with
an overriding focus on safety based on factors
such as the need to ensure a stable of energy
over the long term while addressing global
environmental problems.Greenhouse effect gasesGreenhouse effect gases
Electric power sales and peak power
Power source diversification plan (including power purchased from other utilities)
Japan’s energy supply
Kyushu Electric Power Data Book 2018
Note: Maximum power figures for FY1951 to FY1967 reflect the maximum power at the generating end; for FY1968 to FY2015,
the maximum three-day average power at the transmission end; and for FY2016 to FY2017, the maximum power at the transmission end for the Kyushu area.819243956668492174188050100Japan South
Korea
Italy Germany France UK China U.S.A. Canada Russia(%)Japan depends on overseas
sources for 92% of its primary
energy needs
■しかくEnergy self-sufficiency
■しかくCO2 emissions by energy source0.00.20.40.60.81.01.2Source: Central Research Institute of Electric Power Industry (CRIEPI) Report (July 2016)
(kg-CO2/kWh)
* The calculation of CO2 discharge includes all energy consumed in burning fuel for generation electricity as well as in mining raw materials, construction of facilities,
transportation of fuel, refining, operation, and maintenance, etc.
*As for nuclear power generation, CO2 emissions are calculated by averaging the energy consumed by Japan’s proposed domestic reprocessing of spent nuclear
fuel, known as plu-thermal use (assuming one recycling), disposal of high-level radioactive waste, and other uses. Figures are tallied for boiling water reactors
(BWR; 0.019 kg-CO2) and pressurized water reactors (PWR; 0.020 kg-CO2) and adjusted based on the total installed capacity for each type of facility.
Zero CO2 emission during generation
Scalehydroelectric
power generation
Geothermal
NuclearWindSolarLNG(combined cycle power plant)LNGOilCoal0.079 0.043
0.123 0.098
0.864
0.695 0.476
0.376
0.038 0.026 0.019 0.013 0.011
0.943
0.738
0.599
0.4740500
1,000
1,500
2,00002004006008001,000
1,200
1,400
1951 20172010(Hundreds of millions of kWh) (Tens of thousands of kW)7681,585
(Fiscal year)20001990198019701960FY1951
(year of company’s founding)
Energy sold
Maximum power (right axis)
Composition of generated output
Composition of installed capacity
LNG and other gas
Nuclear
Hydro (30,000 kW or greater)
Japan Electric Power
Exchange
Other*2
Coal-fired
Oil, etc.
Renewable energy
(except FIT electricity)
FIT electricity
Nuclear
Hydro
New energy*1
Geothermal
Coal-fired
LNG and
other gases
Oil, etc.
FY1997
[Actual]
FY2010
[Actual]
FY2014
[Actual]
FY2018
[Actual]
FY1997
[Actual]
FY2010
[Actual]
FY2014
[Actual]
FY2018
[Actual]
(%) (%)020406080100020406080100
*1: Solar, wind, biomass
*2: Electricity procured from other companies
Notes 1: The IEA includes nuclear power when calculating the energy self-sufficiency rate since
uranium, which nuclear power plants use as fuel, can be used for several years after being
imported.
Note 2: Energy self-sufficiency rate (%) = Domestic production / Primary energy supply ×ばつ 100
Note 3: Countries except Japan, FY2015; Japan, FY2016 (estimated)
Sources: "World Energy Balances 2017" (IEA), "Graphical Flip-chart of Nuclear & Energy Related
Topics" (Japan Atomic Energy Relations Organization)14202526141181923231612321191171721611181121428482719168392171927552153932734512180.22540.41
Rising sea
levels
Increased
desertification
Outline of Genkai Nuclear Power Station
Introduction
(Geothermal)
(New energy)
(Nuclear: 0)
Fuel combustion for power generation
Facilities, operation
Energy sold: 4.1 billion kWh
Maximum power: 830,000 kW21
Outline
Unit 2 Unit 4
Unit 1
Unit 3
Unit 1
559 MW
1650 MW 1650 MW 3423 MW 3423 MW
559 MW 1180 MW 1180 MW
Unit 2 Unit 3 Unit 4
Low-enriched uranium dioxide
(approximately 4%)
Low-enriched uranium dioxide
(approximately 4%), mixed
uranium-plutonium oxides
89 tons (approx.) 89 tons (approx.)
October 1975 March 1981
April 2015 March 2019
March 1994 July 1997
Imamura, Genkai-cho, Higashi Matsuura-gun, Saga Pref.
Pressurized water reactor (PWR)
870,000 m2 (approx.)SiteSite area
Generated
output
Start of
operation
Thermal
output
ReactorTypeFuel typeFuelcapacity
(As of March 31, 2019)
Flow of electricity
Power station Steel tower Substation Pole transformer Homes, etc.
TransmissionlineDistributionlineServiceline■しかく
▲さんかく
Legend
Tokunoshima
Okinoerabujima
Yoronjima
Amami Islands
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
Shin-china 19,100
Yoron 2,210
Shin-yoron 5,600
Kuchinoshima 170
▲さんかく
▲さんかく
▲さんかく
▲さんかく
▲さんかく
To Chugoku Electric Power Co., Inc.
TsushimaIkiTanegashima
Yakushima
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
■しかく
Yamagawa 30,000
Shin-tanegashima
24,000
Tanegashima No. 1
16,500
Iwayado
52,000
Ohira
500,000
Omarugawa
1,200,000
Kamishiba
93,200
Tsukabaru 63,050
Morozuka 50,000
Ogiri
25,800
Oyodogawa No. 2
71,300
Reihoku
1,400,000
Hitotsuse
180,000
Toyotama 50,000
Oronoshima 330
Shin-iki 24,000
Genkai NPS 2,360,000*
Shin-arikawa
60,000
Ainoura
875,000
Tenzan
600,000
Matsuura 700,000
Sasuna 5,100
Fukue No. 2
21,000
Uku 3,000
Ashibe 15,000
Izuhara 6,600
Shin-oita 2,825,000
Otake
12,500
Buzan 1,000,000
Matsubara
50,600
Yanagimata
63,800 Takigami 27,500
Karita 360,000
Introduction
OutlineofGenkai
Power
Statio
System
InsidethePower
Station
Securing
Safety
Serious
incident
countermeasures
DecommissioningplanMonitoring
Waste
Treatment
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Surrounding
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Outline of Genkai Nuclear Power Station
Kuchinoerabujima 300
Sendai
1,000,000
Sendai NPS
1,780,000
Oyodogawa No. 1
55,500
Nomamisaki 3,000
Outline of Genkai Nuclear Power Station
End of
operation
*Output for the No. 3 and No. 4 Units is shown as
the Genkai No. 2 Unit ceased operation in April 2019.
Hydroelectric power station
(50 MW or over)
Pumped storage hydroelectric
power station
Thermal power station
Nuclear power station
Geothermal power station
Internal combustion power stations
Wind power station
Main substation
Transmission line (500 kV)
Transmission line (220 kV)
Other company's transmission line
Figures for power plants indicate output (kW).
Nakanoshima 300
Tairajima 150
Suwanosejima 220
Tokara Islands
Akusekijima 150
Kodakarajima 110
Takarajima 200
Tatsugo 60,000
Kikaijima
Shin-kikai
10,600
Kikai 2,100
Naze 21,000
Amami Oshima
Koniya 4,750
Shin-tokunoshima 21,000
Kametsu 7,500
Shin-kokura
1,800,000
Hatchobaru 110,000
Hatchobaru Binary 2,000
Takeshima 190
Kuroshima 320
Ioujima 300
Koshikijima No. 1
13,250
Koshikijima25043System of Nuclear Power Station
Containment
Vessel Spray
Pressure
Accumu-
lator Tank
(Primary System)
(Units 3 and 4)
(Secondary System)
Steam
Water
Fuel Assembly
Fuel Assembly
Spent FuelRackSteam Generator
In the steam generator, hot water
from the reactor converts
secondary system cooling water
into steam.
Fuel Transport
Equipment
Fissionable uranium
about 4%
Fissionable plutonium
about 6%
Less-fissionable
plutonium
about 3%
Less-
fissionable
uranium96%Less-fissionable
uranium, etc.
about 91%
Uranium fuel and mixed-oxide (MOX) fuel
MOX fuel can, in principle, be used as-is in
existing generating facilities.
System
The type of reactor used at Genkai Nuclear Power Station is called a pressurized water reactor (PWR).
One feature of the pressurized water type, shown in the figure below, is the complete separation, through the use of
steam generator heat exchanger tubes, of the system that circulates water through the reactor (primary system) from the
system that supplies steam to the turbine (secondary system), ensuring that no radioactive substances are transmitted
over to the turbine side.
In the reactor, the uranium fuel undergoes nuclear fission, generating large quantities of heat. This heat is transferred to
the water of the primary system, which is then transported to the steam generator by the primary reactor coolant pump.
The primary system water is transported into the steam generator, where it flows through the inner side of the heat
exchanger tubes, transmitting heat through the tube walls to the surrounding secondary system water. The primary
system water is then returned to the reactor.
Meanwhile, the secondary system water is transformed into steam within the steam generator, travels to the turbine, and
drives the turbine-generator to produce electricity.
Once the steam has finished its work at the turbine-generator, it is cooled in the condenser by tubes filled with seawater,
returned to a liquid state, and transported back to the steam generator.
Fuel Assembly Structure
Uranium powder is
b a k e d i n t o h a r d
pellets, which are
loaded into cladded
tubes to form fuel
r o d s . T h e s e f u e l
rods are assembled
into a lattice grid
shape to form the
fuel assembly.HeatExchanger Tubes
Reactor Containment Vessel
The primary containment vessel is an
airtight structure of prestressed concrete
lined on the inside with steel plate, and is
designed to prevent radioactive substances
from escaping to the outside.
Fuel Handling
Building
Spent Fuel
Pit Crane
Condenser
Generator
After driving the turbine, the
steam is cooled by sea water
and converted
back into a liquid state.
Pressurizer
The pressurizer maintains the reactor water at
high pressure, which prevents it from coming
to a boil.
Emergency Core Cooling System
In the unlikely event of an accident in which a rupture in the primary system piping,
etc., results in a loss of water from the system, the emergency core cooling system,
which consists of an accumulator injection system, a high-head injection system, and
a low-head injection system, injects water into the reactor to cool it down, thus
ensuring operational safety.
Reactor Pressure Vessel
This is where the uranium fuel is burned to raise
the temperature of reactor water.
Control Rods
The uranium reaction is controlled by inserting or withdrawing
control rods. If an abnormality occurs, the rods automatically
shut down the reactor.
Turbine
Steam power turns the
turbine, generating
electricity.
The only difference between nuclear power and
thermal power is the fuel used.
From the turbine onward, all the equipment is the same.
Reactor
CoolantPumpPelletMOXfuel
Equipment specifications of Unit 3,4
Cylinder inner diameter
Top: 4.5 m approx.
Bottom: 3.5 m approx.
Total height: 21 m approx.
Heat exchanger tubes
No. of tubes: 3382/generator
Weight: 320 tons approx.
Tube support plate
Steam Generator
Reactor Pressure
Vessel
Introduction
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Outline of Genkai Nuclear Power Station
Equipment specifications of for Unit 3 and 4
Main dimensions
Inner diameter: 4.4 m approx.
Total height: 12.9 m approx.
Cylinder wall thickness:
216 mm approx.
Weight: 410 tons approx.
Uraniumfuel11 mm
approx.
Pellet 8 mm approx.
(slightly enriched UO2)
Spring
Fuel claddingtube(zirconium alloy)
3.9 m
app×ばつ210 mm approx.
4.1 m
approx.
Fuel assembly Fuel rod
Note: Dimensions and other numbers
refer to Genkai Units 3 and 4.
Sea Water
Low Pressure
Injection System (Pump)
High Pressure
Injection System (Pump)
Pressure Accumulator
Injection System (Tank)65
Inside Genkai Nuclear Power Station
Turbine Building
Reactor Containment
Vessel (pccv)
Steam
Generator
Reactor
Coolant
Pump Reactor
Pressure Vessel
Transformer
Condenser
Access
control room
26 meters
below
ground
Ground (EL+11 m)
Base rockSeaWater
Sea Water
Sea Water
Turbine
UraniumFuelPressurizer
Reactor
Auxiliary
Building
Water
Transmission line
ControlRodsSteamFeedwaterpumpCirculating
water pump
Turbine-Generator
(Unit 3)
The steam produced by the
steam generator turns the
t u r b i n e . E l e c t r i c i t y i s
produced by the generator
which is linked directly to the
turbine.
Transformers/Switch Yard
(Units 3 and 4)
The electricity produced by the generator is stepped up to a higher
voltage by transformers and sent out over the transmission lines.
The Switch Yard plays the role of switch between the power station
and transmission lines.
(Units 3 and 4)
Central Control Room
The Central Control Room, with its wide variety of meters,
warning and monitoring devices, operating switches and other
equipment is the brain of the power station. Members of the
Operation Section monitor the reactor, turbine-generator, and
other equipment under a 24-hour-a-day system.
Inside the Containment Vessel
Steam generator
(Unit 3)
The main equipment of the primary system, such as the
reactor and steam generator, is installed inside the reactor
containment vessel.
Pressurizer
Reactor containment vessel
Radiation Controlled Area Access Control Room
Monitoring devices such as a registration system for entry and a body surface
contamination monitor are installed to control access to the radiation-controlled area.
(Units 3 and 4)
Introduction
OutlineofGenkai
Power
Statio
System
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Securing
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Serious
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DecommissioningplanMonitoring
Waste
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Surrounding
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Outline of Genkai Nuclear Power Station87
Multiple Layers of Safety Protect Against Expanding Harm
The major premise of safety measures for nuclear power stations is to
ensure the safety of persons in the surrounding area from danger due to
radioactive materials.
As a result, we use multiple layers of safety measures based on acceptance
of the idea that machinery will break down, and people will make mistakes.
Daily Inspection
In order to confirm the operating
condition of the equipment, patrol
personnel make inspections every day.
Structure built on ground surface Nuclear power station
Base rock
(Ground
surface)
(Ground
surface)
Surface stratum
of ground
Relatively
hard ground
Active fault
Epicenter of
earthquake
Strong base rock
When an earthquake occurs, the
seismic waves are amplified as they
travel from the epicenter to the
ground surface. This causes violent
shaking in structures which are built
on the ground surface.
In contrast, earthquakes have far
less effect on structures such as
nuclear power station which are built
directly on strong base rock, because
the base rock does not amplify the
motion of the quake.
Periodic Inspection
As required by law, equipment is periodically disassembled, inspected,
and tested.
Removal of upper head of the reactor
Overhaul inspection of turbine
Fuel exchange Fuel inspection by monitor television
Exterior view of the Nuclear Power Training
Center
Simulator room (for units 3 and 4)
Periodic Inspection
In addition to thorough implementation
of multiple safety measures for the
equipment, every effort is made to
ensure safety by rigorous training of
operators and maintenance personnel,
which is conducted periodically at the
site and the Training Center.
Nuclear power plant safety
Wall No. 5
Wall No. 4
Wall No. 3
Wall No. 2
Wall No. 1
Fuel rod
(approx. 3.9 m)
(Units 3 and 4)
Safety Features of Nuclear Plant Design
Earthquake countermeasures at nuclear power station
Safety Assurance
1. Prevent abnormalities before
they occur
We implement designs that ensure
ample safety margins, and use equipment
and materials of the highest performance
and quality. In addition, we utilize systems
that are capable of automatically evading
dangerous situations even should the
machinery break down, and that can
prevent the equipment from receiving
operating commands issued in error.
2. Prevent abnormalities that
do occur from burgeoning
into accidents
We have established a monitoring
system for instant notification of
abnormalities, to ensure that the
abnormalities do not lead to accidents.
Moreover, the system can automatically
shut down the reactor should the need
arise.
3. Prevent the release of
radioactive materials in the
unlikely occurrence of an
accident
To prevent the abnormal release of
radioactive materials in the unlikely
occurrence of an accident, the reactor
shall immediately be cooled down and
all radioactive materials be sealed in.
We have a full range
of systems for
ensuring safety.
On‐going
improvement in
operator and maintenance
worker ability
Strict quality
control, rigorous
checks and inspections
Multiple protection design
Even if a fault
occurs
Even if an accident
occurs
Interlock
(prevention of
mishandling)
Fail-safe
(operation for
safety side)
Safe design
to withstand
seismic activity,etc.
Prevents disruption
1 Prevents accidents
spreading
2 Prevents emission
of radioactive materials3Emergency
core cooling
system
Reactor
containment
vessel
cool down
shut down
contain
Early detection
system for disorder
Automatic shut
down system
Introduction
OutlineofGenkai
Power
Statio
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InsidethePower
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Securing
Safety
Serious
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Outline of Genkai Nuclear Power Station
Safety of Nuclear Power Station
Five Walls of Protection
(20 cm thick steel container)
(6.4 mm thick steel sheet)
(Concrete wall approx. 1.3 m thick)
Reactor Containment Vessel
Reactor Containment Vessel
Reactor Pressure Vessel
Fuel Cladding Tubes
(strong metal: zirconium alloy)
Pellet
(Uranium fuel baked hard at high temperature)( )109Measures to ensure safety in the event of a serious accid ent
Genkai Nuclear Power Station has learned from the lessons of the Fukushima Daiichi Nuclear Power Plant and implemented a number of safety-enhancing measures to address both
facility equipment and operational management in the immediate aftermath of an accident. Going forward, we will strive to inspire peace of mind on the part of area residents by
pursuing a voluntary and ongoing program of initiatives to boost safety and reliability.
Preventing
anomalies
Basic approach
Earthquake
Tsunami1*Equipment has been dispersed throughout the
site at elevations of about 11 to 28 m above
sea level.
We’ ve prepositioned an array of
generators* at the site in order to
ensure we can secure the power
needed to prevent a serious acci-
dent.
We’ve taken steps to boost
seismic resistance based
on the maximum anticipat-
ed standard earthquake
ground movement.
The site is situated 11
meters above sea level,
and we have verified that
even the maximum antici-
pated tsunami would not
have an adverse effect on
the safety of the reactor
facility.
We’ ve taken steps based on a
tornado with a maximum wind
speed of 100 meters per second.
*Equipment has been dispersed throughout the
site at elevations of about 11 to 28 m above
sea level.
We’ ve prepositioned an array of
pumps* at the site in order to
ensure the nuclear fuel can be
cooled.
(Also used in Measure .)
Maximum tsunami
height
Sea level + 6 m
Reactor
building
Site height
Sea level
+ 11 m
Compiled with reference to "Comprehensive Nuclear Power Pamphlet 2017"
(published by the Japan Atomic Energy Relations Organization).
Progress of events during the accident at
the Fukushima Daiichi Nuclear Power Plant
Overview of new regulatory standards
Previous regulatory standards
New regulatory standards
Principal safety measures in place at the Genkai Nuclear Power Station (example initiatives)12
Reactors are automatically
shut down.
Offsite power is lost.
All power is lost.
3 Nuclear fuel is damaged.
The plant loses its ability to
cool nuclear fuel.5Radioactive materials are
released into the
atmosphere.4Radioactive materials and
hydrogen leak into the
reactor buildings from the
reactor containment vessels.
Hydrogen accumulates in
the reactor buildings,
causing hydrogen
explosions.
Strengthening the
plant to prepare for
the largest-scale
natural disasters
that are scientifically
possible
Preventing an
anomaly from
expanding2Preventing
damage to
nuclear fuel3Preventing
damage to
reactor
containment
vessels4Preventing
the release
and dispersal
of radioactive
materials
5 To prepare for the unlikely event
that a reactor containment vessel
were to sustain damage, we’ ve
prepositioned water cannons and
underwater curtains at the site.
In addition to adopting more
varied means of cooling reactor
containment vessels, we’ ve
installed hydrogen elimination
systems as a way to lower hydro-
gen concentrations.
Hydrogen,airWater vapor
Elimination
of hydrogen
Electric
heater
Air and
water vapor
Catalytic
plates
Hydrogen,
air, water
vapor
High-capacity pump trucks Portable diesel filling pumps
High-voltage generator trucks
High-capacity air-cooled generators
Storage buildings designed to protect
equipment and supplies
Example: Increasing the
seismic resistance of
tank support structuresTankBefore
reinforcement
After
reinforcement
Water cannons Underwater curtains
Electric hydrogen
incinerator
Static catalyst-type
hydrogen recombination
system
Japan’s new regulatory standards for preventing serious accidents
strengthen legacy standards that were in place prior to the adop-
tion of the new regime, add new standards, and incorporate new
requirements designed to deal with serious accidents in the event
they occur.
*Designated facilities required by regulatory standards to implement readiness measures in anticipation of
serious accidents and other incidents (facilities with equipment such as emergency control rooms for
ensuring that reactors continue to be cooled even in the event of large-scale destruction of the power
station) must implement measures no later than 5 years after the construction plan for the facility is
approved.
Operators are responsible for
determining how to deal with
serious accidents.
Consideration of risks posed
by natural phenomena
Consideration of risks posed
by fire
Reliability of the power supply
Performance of other equipment
Earthquake and tsunami
resilience
Ability to withstand an intentional
impact by an aircraft*
Measures to limit dispersion of
radioactive materials
Measures to prevent damage to
reactor containment vessel
Measures to prevent
core damage
Consideration of risks posed by
internal flooding (new)
Consideration of risks posed
by natural phenomena
with volcanic eruptions, tornadoes,
and forest fires added as new risk factors
Consideration of risks posed
by fire
Reliability of the power supply
Performance of other equipment
Earthquake and tsunami
resilience
Putting in place
facilities and
procedures
capable of dealing
with a serious
accident
Preventing serious
accidents
(prevention of
simultaneous loss
of safety
functionality due to
a common cause)
(New)
Strengthened
or new
Introduction
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Outline of Genkai Nuclear Power Station
Emergency generators
activate and start cooling the
reactors.( )( )4Elimination
of hydrogen1211
Introduction
OutlineofGenkai
Power
Statio
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Securing
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Serious
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Outline of Genkai Nuclear Power Station
Connecting power cables from
a high-voltage generator truck
Power supply training
Supplying power from a high-voltage
generator truck (at night)
Connecting a high-capacity pump truck
Training to supply coolant
Installation of intermediate receiving
tanks (at night)
*We’ve established a 52-member response
team that can take action immediately in the
event of an accident, including outside
normal working hours, on holidays, and at
night.
*Except underground buildings,
underground structures, and foundations
that have not been contaminated with
radioactive materials.
Operational training using a simulator
Emergency plant operation
training
Emergency task force training
Nuclear power plant disaster
training
Dispersal of water by a water cannon
Dismantling and removal of
uncontaminated secondary equipment
(continuing through all phases)
Scope of contamination survey Principal dismantling scope
Principal dismantling scope
Training to prevent the dispersal
of radioactive materials
Training to prepare for a serious accident
Broadly speaking, the decommissioning process consists of four stages.
Preparing for dismantling (starting July 2017)
Equipment is surveyed to
assess the extent of
contamination.
●くろまる
Any radioactive material
that has adhered to pipes
and other equipment is
removed using chemicals
(as part of a cleaning
process).
●くろまる
Dismantling and removing equipment around the reactor
Equipment with a
comparatively low level of
radioactivity is dismantled
and removed.
●くろまる
The fuel extraction
process is completed.
●くろまる
Dismantling and removal of the reactor and related equipment
Once radioactivity levels
have fallen, equipment
such as the reactor
pressure vessel and
steam generator is
dismantled and removed.
●くろまる
Dismantling and removal of buildings
Once contaminants inside
buildings have been
removed, buildings* are
dismantled and removed.
●くろまる
Extraction of spent fuel
Major equipment installed under Japan’s new regulatory standards (illustration)
Command post for use in the event of a
serious accident or other incident
Emergency response
coordination center
To diversify means by which personnel can supply power and cool reactors
Dispersion of mobile equipment such as power supply
trucks and pump trucks
To protect the plant from the effects of off-site fires
(Area about 35 m wide and about 1.3 km long that is free of flammable materials)
Fire belt
Increased to allow diesel generators to
operate for 7 days without off-site support
Additional fuel oil storage tanks
To prevent dispersion of airborne radioactive materials
Measure to protect the site from flying debris
in the event of a tornado
Water cannons
Prevention of damage to the reactor containment vessel in the event of
an impact by an aircraft or other terrorist attack
Designated facilities required by
regulatory standards to implement
readiness measures in anticipation of serious
accidents and other incidents
Safety nets
The existing Hattaura Reservoir will serve as a source
of fresh water in the event of a serious accident or
other incident.
Water supply
Pumps
Power
supplyPondMaximum predicted tsunami height
(Including normal water level)6 mTsunamiSiteelevation11 mNormal water level
Indoor storage so that equipment is not blown
away in the event of a tornado
Garages for portable equipment
Installation of static catalyst-type hydrogen recombination systems and
electric hydrogen incinerators to prevent hydrogen explosions
Equipment to lower hydrogen concentrations
Additional fire detectors, additional fire suppression equipment, etc.
Fire protection
Overview of the decommissioning plan
Principal dismantling scope
Principal dismantling scope1413
Environmental Monitoring
Everyday Life and Radiation
Radiation and Radioactivity
The capacity to emit radiation is called
radioactivity. Materials which have this capability
are called radioactive materials. In other words,
using a lamp as an example, it could be said that
the light bulb is like the radioactive material, the
light emitted by the bulb is radiation, and the
capacity to emit light is radioactivity. Radiation in the Vicinity of Nuclear Power Station
The target value of the radiation dose received by persons in the vicinity of
a nuclear power station as a result of station operation is set at 0.05
millisiverts per year. However, the radiation dose emitted by power stations
in actual operation is held under 0.001 millisiverts. This is far lower than the
radiation we receive from natural sources, and has no effect whatsoever on
the human body.
Radiation Management for Personnel
Working at the Genkai Nuclear Power Station
The radiation doses actually receives by personnel who work at nuclear
power stations average 0.1 millisiverts per year (data from FY2017), far less
than the legal limit of 50 millisiverts per year. Moreover, various
considerations are being taken in terms of both planning and management
to reduce this amount even further.
Natural Radiation and Artificial Radiation
Radiation includes natural radiation, which exists in nature, and artificial
radiation, which includes X-rays used in medical procedures, and emissions
from nuclear power stations and other devices. However, the effect on the
human body is the same regardless of the source, as long as the
radioactive values are the same.
[Radiation exposure during everyday life]1001010.10.010.001100Maximum permissible exposure for
nuclear power station personnel (annual)
Maximum amount of radiation
a substance can emit without
needing to be handled as a
radioactive substance for
safety reasons
100 millisieverts over 5 years and not
greater than 50 millisieverts in any singleyear( )50Chest X-ray
group examination
(1 time)
From outer space
From the earth
Airborne radon
From food0.06Dose target in vicinity
of nuclear power
station (year)0.050.30.330.480.99Emissions from nuclear
power plant (year)
0.001Less than
Natural radiation per
person (year)
2.1(Japanese average)
CT scan chest X-ray
(1 time)
2.4~12.9
Flight from Tokyo
to New York
(round trip)
0.08~0.11
Clearance level
(annual)0.01Unit expressing brightness
(Lux [lx])
Ability to
project light
Ability to give
off radioactivity
(Radioactivity)
Unit expressing the
strength of light
(Candela [cd])
Unit expressing the
strength of radioactivity
(Becquerels [Bq])
Light
Radioactive
material
Flashlight
Radioactivity
Unit expressing the
effect of radioactivity
on the human body
(Sievert [Sv])
*Monitoring stations
Monitoring posts
Continuously measure and monitor radioactivity and airborne radioactive concentrations using gamma ray
monitors and dust monitors.
Continuously measure and monitor radioactivity using gamma ray monitors.
Introduction
OutlineofGenkai
Power
Statio
System
InsidethePower
Station
Securing
Safety
Serious
incident
countermeasures
DecommissioningplanMonitoring
Waste
Treatment
Community
ActivitiesAGuidetothe
Surrounding
Region
Outline of Genkai Nuclear Power Station
Note: The maximum exposure under law is 50 millisiverts per year, and 100
millisiverts over a 5-year period.
No confirmation of clinical
symptoms has been made
below this level.
Radiation in every day life
Whole body
radiation exposure
In order to confirm that there is no change in environmental radiation due to operation of the Genkai
Nuclear Power Station, monitoring stations and monitoring posts* have been installed in the vicinity of the
plant to continuously measure and monitor radioactivity and other parameters. Additionally, crops, soil,
drinking water, fish, seaweed, seawater, and other materials in the area surrounding the facility are
sampled periodically and measured for radioactivity and radioactivity concentration. Further, monitoring
vehicles are used to periodically measure radioactivity in the area surrounding the power station. These
activities are termed environmental monitoring. Measurement results are published by Saga Prefecture,
and the plant publishes environmental radioactivity results.
Monitoring station Environmental sample collection (soil)
Monitoring vehicle Environmental sample collection (Matsuba)
Unit: Millisieverts
Source: Compiled based on "Radiation Q&A"
(The Federation of Electric Power Companies
of Japan)1615
 The liquid and solid wastes which are generated by the power
station are first compacted to reduce their volume and then
packed in drums, which are held (mid‐term storage) under strict
conditions in the solid waste storage facility at the power station.
These drums will eventually be transported to the Low‐ Level Radioactive Waste Disposal Center at
Rokkasho‐mura in Aomori Prefecture for burial (final disposal).
Radioactive waste generated in nuclear power stations includes low‐level radioactive gaseous, liquid,
and solid waste. Gaseous and some liquid wastes are treated appropriately, and then discharged into the
air or the sea after their safety has been confirmed. Moreover, the remainder of the liquid wastes, and the
solid wastes, are treated, sealed into drums, and then stored under strict conditions in a storage building
on‐site.
0 1 2 3km
Rokkasho
Visitors
Center
Oishi-
daira
Yaei-
daira
Obuchi-hamaLow-Level Radioactive Waste Disposal Center
Reprocessing Office
Reprocessing Plant
MOX fuel plant
Enrichment
Disposal Office
lon exchange
equipment
FilterTankReuse
Drums
Water discharge
Released into sea
with seawater used
in cooling
Heating
steamGasLiquid
Solid
Liquid seeps
from rotating
parts of
pumps
Water used
in cleaning
Water used
in laundry
Paper and
cloth used
in work
Replaced parts
Meltable
material
Non- meltable
material
Miscellaneous solid
waste melting furnace
Incinerator
Water used
in analysisworkFilter
Filter
ExhaustgasAsh
StoragetankVitrifying
agent
Monitor
Exhaust duct
Exclusive-use cargo vessel
Cover soil (over 4m)Bedrock
lnspection
tunnel
Drain pipe
Drums
Cement base backfill
Reinforced concretepitPorous concrete layer
Bentonite/sand mixture8 mapprox.
Layout of Rokkasho-mura
Low-Level Radioactive Waste Disposal Center
Low-Level Radioactive Waste Disposal Center
Operator
Scale of site
Start of operation
and storage
Wastes from power stations
are controlled safely to the very last.
Introduction
OutlineofGenkai
Power
Statio
System
InsidethePower
Station
Securing
Safety
Serious
incident
countermeasures
DecommissioningplanMonitoring
Waste
Treatment
Community
ActivitiesAGuidetothe
Surrounding
Region
Outline of Genkai Nuclear Power Station
Gas accumulates
in top of tank
Gas surge tank Activated charcoal
Building
ventilation
Monitor
Radioactivity is
monitored.
Filter
Molten
material
Exhaust
gas pipe
ExhaustgasPacific
Ocean
Takahoko
Marsh
To Futamata
Route338Futamata
River
Oippe
River
Wind power
generation facility
Inside solid waste storage facility
Management of Wastes
Treatment of Radioactive Waste
Rokkasho-mura
Aomori Prefecture
Sampling to verify
that waste can
be discharged
Low-level radioactive waste
Exhaust
gas pipe
Monitor
Steam
Returntowater
Monitor
Bitumen solidification equipment
Bitumen
Cooked down
waste liquid
Storage building
Building of reinforced concrete
construction
December 1992
200,000 m3
(Equivalent to 1 million drums)
To be expanded to 600,000 m3
(Equivalent to 3 million drums)
*1drum=200 liters
JAPAN NUCLEAR FUEL LIMITED
(JNFL)
Mutsu Bay
Aomori Prefecture
Mutsu-OgawaraPortTo Misawa
High Level
Radioactive Waste
Storage Control
Rokkasho
substation
National Petroleum
Storage Base
Uranium
Enrichment Plant
To Mutsu
Obuchi
Marsh
(Referrence)1817
Recreation Plaza
Genkai Research Institute of Medicinal Plants
Cleaning road curve mirrors
Empty can and trash collection
Cleanup at a social welfare facility
Volunteer activities
Building a Better Community
Barbecue area
Sledding slope
Outdoor stage
Picnic area
Health and
exercise equipment
Genkai Energy Park Expansion Area
Outline
Facility Outline
Together with the Region
Science Pavilion
Kyushu Furusato Pavilion
PR Center Taiyo-no-Hiroba Decorative plant greenhouse
Grassy plaza
Jabu-Jabu Pond
In operating a nuclear power plant, the
cooperation of everyone in the area is
indispensable. To deepen the understanding and
friendly feeling of residents toward Genkai Nuclear
Power Plant, we are fully involved in everyday
dialogue activities, volunteer activities, sports, and
other parts of the life of the community.
We are also working to
i m p r o v e t h e s o c i a l
infrastructure of the area. For
example, to improve welfare
services, we have donated
funds for the construction of
public facilities under the three
main laws for the promotion of
power station construction.
Japanese croquet
Events
Introduction
OutlineofGenkai
Power
Statio
System
InsidethePower
Station
Securing
Safety
Serious
incident
countermeasures
DecommissioningplanMonitoring
Waste
Treatment
Community
ActivitiesAGuidetothe
Surrounding
Region
Outline of Genkai Nuclear Power Station
Welcome to Genkai Energy Park
At Genkai Energy Park, which opened in March 2000, visitors are introduced to nuclear energy as they
walk around and see its facilities. It is both a learning and playing experience.
The park's main attraction, the PR Center, consists of two facilities, the Science Pavilion and Kyushu
Furusato Pavilion. The former exhibits, for the first time in Japan, a full‐view reactor mock‐up, while the
latter introduces traditional crafts and folklore from all over Kyushu. Other facilities include the
Taiyo‐no‐Hiroba with outdoor play equipment and Jabu‐Jabu Pond, and the "Visitor's conservatory". In March 2006, Yuchuntei Awatsuki, built in traditional Japanese style with a Japanese garden, was
completed in the Camellia Park to mark Genkai Energy Power Station's 30th anniversary. Calming and
wood‐scented, Awatsuki can be used for various events such as tea ceremonies, haiku meetings, and
flower arrangement (free of charge; reservations required).
It is operating in conjunction with the adjoining Genkaicho Next Generation Energy Park Asupia, offering
an expanded variety of outdoor facilities.
Yuchuntei Awatsuki
Visitor’ s conservatory
Taiyo-no-Hiroba
Cherry tree
Promenade
Outdoor play
equipment
From two weeks in advance
From the first day of the month in which the day
falling three months before the desired
reservation falls
Yuchuntei
Awatsuki
Tennis courts
・Address: 4112-1 Oaza Imamura, Genkai-cho,
Higashi-Matsuura-gun, Saga 847-1441 JAPAN
Tel: 0955-52-6409 Fax: 0955-52-3796
・Access: Take the Showa Bus from Karatsu (Oteguchi Bus
Center) and get off at the Genkai Energy Park stop
(Genkai Nuclear Power Station Entrance). Takes about 40
minutes.
・Hours: 9:00 to 17:00; admission free
・Closed: New Year’s holidays (Dec. 29 to Jan. 2), third
Monday of each month (or next day, if a holiday )
・Tour courses: Genkai Energy Park, Nuclear Power Training
Center, Visitor,s Conservatory
・Please contact Genkai Energy Park to make reservations
(required) for the tennis courts or Yuchuntei Awatsuki.
These facilities are open to the public free of charge.
Scale of structure
Building area
Total floor area
Maximum height
of building
1,300 m2
approx.
1,520 m2
approx.
18 m approx.
Scale of structure
Building area
Total floor area
Maximum height of building
9,700 m2
approx.
30 m approx.
Ferroconcrete structure
(a basement and four stories )
Ferroconcrete structure
(one basement and one
above-ground floor)
5,400 m2
approx.2019
Illustration:Kiyohiko Matsushita
Guide to the Surrounding Region
花と
冒険の島123456789181615171011121314
Saga Prefectural Nagoya Castle
Museum3Dates from the 9th year of Tensho (1591). The remains
of the castle constructed by Hideyoshi as the main base
for an expedition to Korea. Ranks among the largest of
Momoyama period castles remaining today in Japan.
The Museum houses a collection of documents on the
history of the castle and its vicissitudes.
Genkai Marine Observation Tower1From the tower built out from the tip of Cape Hato, it is
possible to observe to a depth of 7 meters below water
level.
Windview Hill Gardens4Yobuko-ohashi5Ruins of Nagoya Castle2Genkai Nuclear Power Station6Mishima Park8Tsuruno-iwaya10Carved in the walls of this natural cave are 120 noble
images from the 88 sites of Shikoku and 33 sites of
Saikoku, including images of Nio, Jizo, and Oyamoto
Nyorai.
The strange scenery in this chilly cave holds a
mysterious fascination.
Flower Adventure Island11Cross the fairy bridge to Never-Never land in the story
of Peter Pan. A place for the whole family to enjoy, with
a pirate ship built of logs, Crocodile Island, Fantasy
Island, and other special places.
Kariya Bay9Irohajima12Kirigo Peonies13Descendants of the peonies imported from Ming
China, which were loved by the former lord of Karatsu
Higashi Matsuura, Hata Mikawanokami, and his wife,
Hidenomae. Every year in mid-April, more than 500 of
these large flowers bloom announcing the arrival of
spring in Hizen-machi, Karatsu City.
Ukidake14Ukidake (Hamatama-machi, Karatsu City)
View from Karatsu Castle.
Niji-no-Matsubara15O n e o f J a p a n ’ s t h r e e g r e a t p i n e g r o v e s ,
Niji-no-Matsubara is 5 kilometers long and 1 kilometer
wide, forming a rainbow-like arch along the sea and
white sand.
Planted by Terasawa Shimanokami Hirotake as a
windbreak in the Bunroku era. Seen from Mt. Kagami,
this is one of Japan’ s unsurpassed scenes of natural
beauty.
Hikiyama Float Exhibition Hall16This exhibition hall houses the 14 Festival Floats,
which play the main role in the Karatsu-Kunchi that
enlivens the autumn season in Karatsu.
The completion of the floats require dyears of work
and masterly skill. These are truly mobile works of art.
The festival itself has also been designated as an
important intangible folk cultural property by the
government.
Karatsu Castle17Construction of this castle by Hideyoshi’s follower
Terasawa Shimanokami Hirotaka was completed in the
13th year of Keicho (1608). Also called the Dancing
Crane Castle for its beautiful silhouette. Important
historical documents are displayed on each floor.
Nanatsu-gama18Genkai, a beautiful town blessed with
blue sea and a fascinating history Genkai Town
Terraced paddy field in Hamanoura7N
Introduction
OutlineofGenkai
Power
Statio
System
InsidethePower
Station
Securing
Safety
Serious
incident
countermeasures
DecommissioningplanMonitoring
Waste
Treatment
Community
ActivitiesAGuidetothe
Surrounding
Region
Outline of Genkai Nuclear Power Station
Flower Adventure Island
Kirigo
peonies
Matsuura City
JR Hamazaki St.
JR Hamazaki St.
JR Watada St.
JR Karatsu St.
JR Watada St.
JR Karatsu St.
Karatsu Castle
Karatsu Castle
JR Nishi-
Karatsu St.
JR Nishi-
Karatsu St.
Kirigo
peonies
Peony and
Green
Hill Park
Peony and
Green
Hill Park
Rte. 204
Rte. 204JROnizuka St.JROnizuka St.
Genkai Nuclear
Power Station
Undersea
observatory tower
Undersea
observatory tower
JR Niji-no-
Matsubarai St.
Takashima Hizen
Ohashi Bridge
Takashima Hizen
Ohashi Bridge
Genkai Nuclear Power Station
Genkai Energy Park
Nijoshikaka IC
Hamatama IC
Nishi-Kyushu
Expressway
Windview Hill
Gardens
Kabeshima
Kabeshima
Hato-misaki
Yobuko-ohashi
Yobuko-ohashi
Jiira
Jiira
Nanatsu-gama
Nanatsu-gama
Kashiwajima
Kashiwajima
Tategami
(Meoto iwa)
Tategami
(Meoto Iwa)
Rte. 204
Rte. 204
Iwano
Nagoya-ohashi
Nagoya-ohashi
Ruins of
Nagoya Castle
Ruins of
Nagoya Castle
Prefectural
Nagoya Castle
Museum
Prefectural
Nagoya Castle
Museum
Genkai Town
Nousa
MatsuuraCityUkidake
Mt. Kagami
to Fukuoka
to Fukuoka
Karatsu Bay
Karatsu Bay
Kakura
Kakura
Takashima
Takashima
Nagasaki Pref.
Imari City
KaratsuCityTerraced paddy field
in Hamanoura
Terraced paddy field
in Hamanoura
Research Institute
of Medicinal Plants
Asupia
Hoshika
Mishima Park
Mishima Park
Kariya
Kariya
Kariya Bay
Kariya Bay
Teraura
Teraura
Tsuruno-iwaya
Tsuruno-iwaya
Terraced paddy field
in Tsuchiya
Terraced paddy field
in Tsuchiya
Rte. 204
Rte. 204
Terraced paddy field
in Oura
Terraced paddy field
in Oura
Takakushi
Irohajima
Irohajima
Flower Adventure Island
Niji-no-
Matsubara
Niji-no-
Matsubara
Kagami
Shrine
Hikiyama
Float ExhibitionHallHikiyama
Float Exhibition
Hall JR Higashi-
Karatsu St.
JR Higashi-
Karatsu St.
JR Niji-no-
Matsubara St.
Karatsu IC
Karatsuchichika
yamada IC
Kitahata IC
Minamihata-
Taniguchi IC
Large
agricultural
serviceroadLarge
agricultural
serviceroad2221For more information about the Genkai Nuclear Power Station, visit
http://www.kyuden.co.jp/genkai-index.html
Introduction to Genkai Nuclear Power Station
Publisher: Environmental and Public Relations Group
Genkai Nuclear Power Station
Kyushu Electric Power Co., Inc.
Phone: 0955-52-6821
Issued in September 2019