Decommissioning and dismantlement of the Stade nuclear power ...
Decommissioning and dismantlement of the Stade nuclear power plant –
from nuclear power plant to green fields
Stade
Contents
3|The Stade nuclear power station – a short history
4|What does ”decommissioning and dismantlement”
actually mean?
5|Why is the Stade plant being decommissioned?
Commercial factors
6|What experience do we have when
it comes to decommissioning nuclear power stations?
Dismantlement methods
Expertise that’s based on experience
Decommissioned and dismantled nuclear power stations in Germany
Reactor types
The Stade nuclear power station: special features
12 | What, exactly, does the dismantling process involve?
From full-load operation to decommissioning:
The transition phase:
Dismantlement Phases I - IV
Conventional dismantling
Timeframe
20 | What does decommissioning mean for Stade’s
employees?
Different workforce structures required
Staffing cutbacks
22 | What happens to the dismantled parts and materials?
Disposal methods
Waste material categories
Mechanical breakdown of materials
Decontamination
Safety clearance
Radioactive waste
28 | What happens to the vacant site?
Green fields
30 | What is the regulatory environment under which
decommissioning is performed?
Statutes and regulations
Clearance procedures
Environmental impact analysis
32 | The Stade nuclear power station in brief
The Stade nuclear power station – a short history
July 28, 1967 Nordwestdeutsche Kraftwerke AG applies for a government permit
to build and operate a nuclear power station near the German city of Stade
October 1967 Siemens AG is awarded the contract to build a turnkey nuclear power station
November 17, 1967 Permit for earthworks granted; construction works begin
March 1968 Plant operating company Kernkraftwerk Stade GmbH established
June 1971 Non-nuclear plant and equipment commissioned
January 7, 1972 Permit granted for commissioning of nuclear plant and equipment
January 8, 1972 Reactor attains first criticality
January 29, 1972 Stade begins to feed electricity into the public grid
March 26, 1972 First test at full load
May 19, 1972 Official hand-over to Kernkraftwerk Stade GmbH and start of commercial
on-load operation
1984 Stade starts cogenerating process heat for a neighboring salt works
Fall 2000 For commercial reasons, E.ON Kernkraft GmbH and HEW AG decide to
decommission and dismantle Stade, starting in the fall of 2003
July 2001 Application for permit for decommissioning and dismantlement (Phase I)
Fall 2001 Cumulative volume of electric energy generated since commissioning
totals 140,744 million kilowatt-hours
November 14, 2003 Reactor shutdown
2004 to 2008 Further applications for dismantlement permits (Phases II to IV)
End of 2014 Stade site released from Germany’s statutory nuclear facility
monitoring regime
By end of 2015 Conventional demolition of remaining building structures
3
Decommissioning in the broader sense
Decommissioning in the
narrow sense
_ permanent shutdown
of reactor
_ permanent shutdown
of remaining plant
What does “decommissioning and
dismantlement” actually mean?
Dismantlement
_ disassembly, decontamination,
and removal
from site of remaining
plant and materials
Decommissioning a nuclear power station means
shutting it down permanently.
Once it has been shut down, it is “dismantled,”
meaning it is gradually broken down into its constituent
parts. These parts then undergo different
types of treatment, depending on the level of
contamination, after which they are packaged and
removed from the site. Following dismantlement,
the site is completely cleared and made available
for unrestricted use.
The term “decommissioning” is often used more
loosely to describe everything that happens after
the plant is permanently taken offline, including
the shut-down and dismantlement processes.
Why is the Stade plant being decommissioned?
There are actually no technical reasons for decommissioning the Stade station at present.
The decision to decommission the facility was made exclusively on commercial grounds.
In July 2001, E.ON Kernkraft lodged an application for a permit for the initial dismantlement
phase, residual plant operations, and the construction of a temporary storage facility for the
radioactive waste from the dismantlement of the station’s nuclear plant and equipment.
Possible reasons for decommission nuclear power stations
political
_ nuclear exit strategy
agreement between the
German State and the
country’s energy industry
legal
_ Germany’s Atomic
Energy Act (AtG)
_ Germany’s Radiation
Protection Regulations
(StSV)
technical
Commercial factors
_ service life of key
components
As a result of electricity market liberalization,
Germany’s energy utilities are in the process of
downsizing both their conventional and nuclear
generation fleets in order to eliminate costly
excess generation capacity.
The Stade nuclear power station is no longer
economic. With a net installed capacity of 630 MW,
the facility delivers only about half the electric output
of most other German nuclear power stations,
but is equally if not more expensive to operate.
Another key factor in the decision to decommission
the station is the levy on water supplies
imposed by the government of Lower Saxony, the
German state in which Stade is located. The introduction
of this levy on water taken from the Elbe
River for plant cooling purposes resulted in some
8 million in additional costs for the Stade facility
per year.
In any event, the Stade facility would have
exhausted its residual generation quota – set
under Germany’s nuclear exit strategy – some time
in 2004. Thus, E.ON Kernkraft’s decision to decommission
the plant in 2003 cut short its service life by
only about one year.
commercial
_ excess generation
capacity
_ liberalized energy market
_ government levies on
supplies of cooling water
5
What experience do we have when it comes to
decommissioning nuclear power stations?
Germany’s original decision to use nuclear energy
for commercial electric generation came only after
considerable research on radioactive materials and
testing of various types of nuclear reactor. Dealing
with radioactive buildings, machines, installations,
and assemblies is therefore nothing new for
Germany’s nuclear energy industry.
Several nuclear power station decommissioning
projects have already been authorized and completed
in Germany, allowing the relevant energy companies
to trial a wide range of methods and processes.
The local industry also benefits from the decommissioning
expertise gathered by other countries.
Dismantlement methods
Germany’s nuclear power station operators carried
out a number of conceptual studies on decommissioning
nuclear power stations as early as the mid-
1970’s. These studies developed and compared two
decommissioning methods: dismantlement after a
period of safe enclosure (SAFESTOR) and immediate
dismantlement (DECON).
The first of these two methods involves dismantling
the facility after several decades of safe enclosure.
The enclosure period allows the radioactivity
to decay, so that dismantling can take place under
lower levels of radioactive exposure.
As the term suggests, immediate dismantlement
involves dismantling the plant as soon as it is taken
out of service. The advantage of this method is that
the plant’s existing technical systems can be used for
pre-dismantlement work such as decontamination.
Hybrid dismantlement methods can also be used –
such as enclosing only certain parts of the plant,
while dismantling the rest immediately.
Decommissioning nuclear power stations
Implementation of safe
enclosure measures
Safe enclosure period
(about 30 years)
Dismantlement
On-load operation
Transition phase
Immediate dismantlement
7
8
Expertise that’s based on experience
Germany’s nuclear energy industry has already permanently decommissioned
several nuclear power stations, including two where the sites have already been
returned to ‘green fields’. The map on the page opposite provides an overview
of Germany’s nuclear station decommissioning and dismantlement projects.
Facilities that have been fully dismantled are marked in blue.
Dismantling in progress
at the Würgassen plant
The Würgassen dismantlement project again highlights
the fact that the immediate dismantlement
method does not pose any great challenges.
This tried and proven process was selected for the
Stade facility because it retains jobs and therefore
also plant-specific expertise which helps to expedite
the dismantlement process.
One key difference between the Würgassen
and Stade facilities is that the former uses a boiling
water reactor (BWR), whereas the latter uses a pressurized
water reactor (PWR). The implications of this
in terms of the dismantlement process are explained
on the following pages.
Decommissioned and dismantled nuclear power stations in Germany
THTR-300 Hamm-Uentrop
(thorium high
temperature reactor)
Mülheim-Kärlich Nuclear Power Station
(PWR)
Lingen Nuclear Power Station
(BWR)
AVR-Versuchskraftwerk Jülich facility
(experimental high temperature reactor)
Karlsruhe MZFR Multipurpose
Research Reactor
(PWR)
fully dismantled facility
decommissioned facility
Stade Nuclear Power Station
(PWR)
Würgassen Nuclear Power Station
(BWR) – owned by E.ON Kernkraft
Kahl Nuclear Power Station
(BWR)
Großwelzheim facility
(superheated steam reactor)
Compact Sodium-Cooled
Nuclear Reactor I/II (KNK), Karlsruhe
Grundremmingen A
Nuclear Power Station
(BWR)
Greifswald Nuclear Power Station
(PWR)
Rheinsberg Nuclear Power Station
(PWR)
Niederaichbach Nuclear Power Station
(heavy water reactor/HWR)
9
10
Reactor types
In PWR nuclear power stations, the reactor heats
water in a fully self-contained circuit known as
the primary cooling loop. A heat exchanger transfers
the heat energy in the primary cooling loop
to a secondary cooling loop, causing the water in
the secondary loop to evaporate. The steam thus
generated is then ducted to the turbines. In this
way, the turbines are kept separate from the primary
loop, which makes them significantly easier
and safer to handle.
In fact, the structural design of the entire
facility was based on the principle of isolating all
sections which could potentially get exposed to
radioactivity. Only the reactor building and the
reactor auxiliary building are located in what is
known as the radiation control area; the turbine
room, comprising the turbines and the generator,
are located outside of this area.
Radiation control areas
PWR plant
BWR plant
Radiation control area
The diagram below further illustrates the key
differ-ences between pressurized water reactors
(such as Stade) and boiling water reactors (such
as Würgassen). In BWR plants, the radiation control
area encompasses the entire block, including the
turbine room. In PWR plants like Stade, on the other
hand, the reactor building is clearly separated from
the turbine room.
1
1 2
2
1 Turbine room
2 Reactor building
The Stade nuclear power station:
special features
Stade was Germany’s very first purely commercial
nuclear power station to use PWR technology. Its installed
capacity is now about half that of its more
modern counterparts. However, when it was commissioned
it ranked as Germany’s highest-output PWR
nuclear power station.
In 1984, Stade also became Germany’s first nuclear
power station to cogenerate process heat. The heat,
which is supplied to a neighboring salt works, is generated
via a tertiary cooling loop. Extracting useable
steam in this manner raises the overall efficiency
of the plant.
Pressurized water reactor
1
2
3
1 Reactor pressure vessel
2 Primary coolant pump
3 Steam generator
4 Water separator and
reheater
1
3
10
4
11
9
10
4
9
5 Turbines
6 Generator
7 Transformer
8 Condenser
9 Heat exchanger
5
8
13
12
10 Feedheater
11 Feedwater pump
12 Cooling-water pump
13 Cooling-water filter
14 Cooling pond
6
7
14
11
What, exactly, does the dismantling process involve?
Dismantling a large-scale nuclear facility involves
the step-by-step removal of all plant components and
thus requires the same level of precision planning as
building one. The dismantling process also clearly
distinguishes between nuclear and non-nuclear plant
components.
Most plant components and systems that are
not exposed to nuclear radiation can be dismantled
and removed immediately after plant shutdown –
provided they are not required for the rest of the
dismantling process.
From full-load operation to
decommissioning: the transition phase
The changeover from normal, full-load operation
to the dismantlement phase requires a number of
important changes to the plant’s operating processes.
To ensure this happens efficiently and safely,
the dismantlement plan allows for a so-called transition
phase of about one and a half years. During this
period, preparations are made for the disassembly
and removal of plant components and systems,
covering the following areas in particular:
_ the removal of spent fuel rods from the site
_ system decontamination measures
_ the isolation and shut-down of systems that
are no longer required.
Dismantlement of the power station’s nuclear plant
components starts once the transition phase has
been completed and the permit for decommissioning
has been granted. At Stade, the dismantlement
process has been divided into four phases. Each of
these phases is subject to the government regulations
applicable at the time and the associated
approval procedures.
13
14
Dismantlement Phase I
1
2
1 Materials air lock and air recirculation unit
2 Flood tanks
During the first dismantlement phase the necessary
logistics systems are established within the radiation
control area and as many non-required nuclear
systems as possible are removed to create more
space for subsequent dismantling work. The dismantlement
of the larger plant components is also
planned at this time.
The diagram above shows some of the systems
that are dismantled and removed during
Dismantlement Phase I:
3
1
4
3 Control rod assembly
4 Pressurized water tanks
_ The flood tanks that feed the primary loop
during start-up and shut-down.
Dismantling these helps to create extra space
for the treatment and interim storage of waste
materials from the dismantlement process.
_ The control rod assembly.
The individual components making up this
assembly are also small and their dismantlement,
which frees up space in the reactor chamber,
is uncomplicated.
_ The pressurized emergency cooling tanks and
other nuclear-contaminated systems that are no
longer required for the subsequent dismantlement
work.
However, some non-nuclear plant components
such as the live-steam and feedwater systems,
the emergency diesel generator set, and turbine
and generator components are also disassembled
and removed during this period.
Dismantlement Phase II
1 Steam generator
2Primary coolant pipe system, including pumps
2
The second dismantlement phase focuses on the
larger nuclear plant components and involves
preparatory work followed by actual dismantlement
and removal.
The components concerned include the primary
coolant pipe system, including:
_ the pumps,
_ the steam generator.
1
The components shown in the diagram are examples
only; other contaminated components not shown in
the diagram are also removed during this phase.
15
16
Dismantlement Phase III
1 Concrete slab
2 Fuel racks
2
1
3
4
3Reactor pressure vessel
4 Concrete shielding
The third dismantlement phase involves dismantling
and removing the most contaminated nuclear plant
components. Neutrons escaping from the reactor have
made these components radioactive; they can not be
decontaminated. As highlighted in the diagram above,
these components include:
_ the reactor pressure vessel,
_ the concrete shielding that encloses the reactor
pressure vessel (known as the biological shield),
_ the overhead concrete slab that shields the reactor
room,
_ the fuel racks in the former fuel storage tank,
and various fixed and moveable pressure vessel
components.
Dismantlement Phase IV
1 Polar crane
2 Fuel transfer platform
2
1
3Ventilation plant
4Water purification plant
In the final nuclear dismantlement phase, all the
systems remaining in the radiation control area are
gradually dismantled and removed. The last systems
to be removed are the water purification and ventilation
plants.
The remaining building structures in the control
area are then cleaned and decontaminated so that
they meet statutory requirements for safety clearance.
The radiation control area is thus gradually
scaled down and eliminated.
3
4
17
18
Elbe River
The final stage involves all such site clearing and decontamination
work as is necessary to ensure the site meets statutory radiation safety
clearance requirements. Once this has been achieved, the site is released
from Germany’s statutory nuclear facility control and permit regime.
Conventional dismantling
Planned control area elimination process
Step 1
Containment
Step 2
Reactor building
Step 3
Auxiliary services building
Step 4
Entrance to radiation control area,
stack
The final step in dismantling the Stade plant
involves the demolition and removal of the remaining
buildings and structures from the site. Conventional
demolition methods can be used during this
phase because the site is no longer subject to statutory
nuclear facility control and permit requirements.
The scrap concrete and steel generated by the
demolition process is recycled wherever possible.
The decommissioning and dismantling project is
officially at an end once the site has been restored
to green fields.
Timeframe
When the Stade nuclear power station was shut
down on November 14, 2003, preparations for the
plant’s subsequent dismantlement were already
well underway.
The current transition phase, which began after
shutdown, involves the removal of the remaining fuel
rods. Once this is done, deconstruction can begin in
accordance with the statutory regulations governing
the initial dismantlement phase. We estimate this
will happen midway through 2005.
The dismantling of the plant and installations
in the radiation control area will take place in four
phases, as described earlier. This process is expected
to take almost ten years and will therefore probably
not be completed until the end of 2014. The only
task remaining once the site has been released
from Germany’s statutory nuclear facility control
and permit regime is to demolish the buildings and
structures. This is scheduled to take place in 2015.
The phases described above are independent of
each other and can therefore overlap. The permit
application for Phase I was lodged in July 2001.
Permit applications will be lodged in good time for
the scheduled start of each of the remaining phases.
Decommissioning timetable
2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016
On-load operation
Transition
phase
Construction
Residual operation (immediate dismantlement)
Dismantlement of non-nuclear components
Dismantlement of nuclear components
Phase I
Operation
Phase II
Phase III
Storage facility for radioactive waste
Phase IV
Building
demolition
19
What does decommissioning mean for Stade’s employees?
Different workforce structures required
Compared to daily production operations, plant
decommissioning involves fundamentally different
work processes. This has important implications for
the plant’s organizational structures as well as the
makeup and size of its workforce.
The primary focus during the Stade facility’s
service life was on ensuring safe, reliable plant operation.
Now that the facility is being decommissioned,
its safety systems and installations will gradually be
taken out of service. Naturally, this will also impact
the employees who are working in this area.
However, decommissioning also brings with it new
task areas and responsibilities. For example, it will
create opportunities for employees who are skilled
in the use of the dismantling equipment. We will
also need additional radiation protection specialists.
However, over the long term there will be a net
decline in employee numbers.
Staffing cutbacks
E.ON Kernkraft GmbH has a twofold strategy for
minimizing the impact of anticipated job losses.
Our older employees, including those who reach
the required age before the end of the dismantling
project, have the opportunity to participate in a
special early retirement program. Exempt from this
are those older staff members who possess skills
that are essential for the dismantling project.
The second strategy relates to the redeployment
of personnel to other E.ON Kernkraft locations. Those
affected will need to relocate and, in all probability,
retrain. This option will most likely be more attractive
to the company’s younger employees.
21
What happens to the dismantled parts and materials?
Waste material
from the radiation
control area
Various measurements, tests, and treatment processes
Safety clearance
as re-usable/recyclable
waste or conventionalnon-recyclable
waste
Controlled re-use Radioactive waste
By far most of the material resulting from the
dismantlement process is not radioactively contaminated
and can therefore be treated like normal concrete
and steel demolition waste. This includes the
material removed from the radioactive control area.
However, because of the risk that material from the
control area may be contaminated, all components
from this area need to undergo rigorous testing.
Once testing is complete, the disposal technicians
individually determine how each component is to
be disposed of.
Material that is neither contaminated nor radioactive
may be suitable for immediate re-use or recycling
in other areas. For example, the waste concrete
from the building demolition process counts is standard
building rubble and can be re-used in the construction
industry. Most of the metal components are
recyclable scrap metal. The diagram below shows the
main disposal methods for the waste material from
the radiation control area.
Disposal methods
There are a range of disposal methods for the
waste material from the radiation control area.
These include:
_ unrestricted safety clearance for re-use or
recycling
_ scrap metal: safety clearance for recycling subject
to certain conditions
_ safety clearance for disposal as conventional,
non-recyclable waste (for landfills)
_ controlled re-use by the nuclear industry
_ safe disposal as radioactive waste
The materials are classified into the above clearance
categories in accordance with the rules and
radiation exposure limit values laid down in
Germany’s Radiation Protection Regulations (StSV).
Each control area component is tested to determine
its contamination or radioactivity status, classified,
and assigned an appropriate disposal method.
Each component is then disassembled and/or broken
down and, where applicable, decontaminated so that
it meets the requirements of the selected disposal
method.
Dismantling work in progress at
the Würgassen NPP
23
24
Plant dismantlement:
waste material categories
Based on its experience of past decommissioning
projects and its intimate knowledge of the Stade
facility, E.ON Kernkraft GmbH is able to estimate
with considerable accuracy the volume and percentages
of materials that will be allocated to each
clearance category, as shown in the chart below.
Materials categories: percentages and volumes
Area
in Mg (megagrams)
Clearance
(restricted and
unrestricted)
272,100 Mg
Non-nuclear
area
127,540 Mg
Nuclear
area
Controlled
re-use
Detailed view:
Nuclear area
Radioactive
waste
97,2 % Safety
clearance
0,4 % Controlled
re-use
2,4 % Radioactive
waste
Nuclear area 124,005 (97.2 %) 545 (0.4 %) 2,990 (2.4 %) 127,540 (100 %)
Non-nuclear area 272,100 - - 272,100
Total 396,105 545 2,990 399,640
Total
Mechanical breakdown of materials
During the dismantlement process large plant
components need to be cut up into smaller sections.
Conventional tools such as large blade saws, hydraulic
shears, cutting torches, and metal shredders are
used for this purpose. Slow-running machinery is
employed wherever possible to prevent the creation
of aerosols.
The tools and equipment are set up in the
necessary configuration in the areas designated for
dismantling/cutting, decontamination, and waste
treatment. Minimizing the decommissioning personnel’s
exposure to radiation is the paramount criterion
for selecting which tools and methods to use.
The work processes are also designed to prevent
the buildup of dust and grime. Certain processes are
even performed in sealed areas with their own, separate
air handling systems or in containers. In these
areas, the air is extracted and filtered, thereby preventing
the spread of radioactivity within the plant
and protecting the environment from radioactive
emissions.
Wherever possible, the plant components are
broken down into pieces small enough to fit into
special containers, which are then transported to
further treatment stations. After disassembly and
cutting, each item is thoroughly cleaned. Extremely
sensitive measuring instruments are then used to
determine each item’s level of radioactivity or surface
contamination. Depending on the outcome of these
measurements, each item is either submitted for
final clearance testing or is first decontaminated
and then submitted for final clearance testing.
Decontamination
In most cases, radioactivity is confined to mere
surface contamination. When the Stade plant was
built, many of the components used were coated
with a special sealant designed to facilitate decontamination.
These types of components can in most
cases be completely decontaminated by thorough
washing or abrasion. Where contamination has penetrated
deep into the material via cracks and pores it
is removed by mechanical or chemical means.
The following decontamination methods are used:
_ steel grit blasting,
_ water blasting, and
_ chemical flushing.
Dry steel grit blasting is a highly effective decontamination
method for disassembled and cut-up components
with readily accessible surfaces. It involves
grinding the surface off the components by bombarding
them with a jet of pin-head-sized steel
grains traveling at nearly the speed of sound.
Chemical flushing, on the other hand, is used for
decontaminating whole systems and assemblies prior
to disassembly. The final decontamination step is a
simple matter of isolating the contaminated particles
from the steel grit or chemical solution.
Decontamination keeps the volume of secondary
radioactive waste to an absolute minimum and significantly
reduces the amount of radiation to which
the plant’s personnel are exposed during subsequent
dismantling work. The decontamination methods
used are specially tailored to the method of disposal.
25
26
Safety clearance
The material from the dismantlement process must
meet extremely stringent standards to qualify for
unrestricted clearance for conventional recycling or
re-use. This involves subjecting it to a series of tests:
Following preliminary testing for the presence of
radioactivity, disassembly and dismembering, and
decontamination, the material is subjected to socalled
orientation testing. This entails direct measurements
of surface contamination, the primary aim of
which is to determine the distribution of radioactivity
across the surfaces.
Final clearance testing is designed to determine
whether the material meets statutory requirements
for clearance. It involves a range of different measurement
and testing methods, which are also subject
to differing requirements in terms of radioactivity
distribution and are thus closely associated with
orientation testing.
Under certain conditions the power plant operator
will also conduct so-called control measurements.
These involve both direct measurements and the
taking of samples for laboratory analysis.
Once all the tests and measurements have been
performed, the complete set of clearance documents
is submitted to the competent statutory atomic energy
regulatory body. The material can only be removed
from the plant site after this body has given its
approval and the plant’s designated radiation protection
officer has issued final safety clearance.
The clearance process
Disassembly, dismembering
Decontamination
Preliminary/
orientation testing
Final clearance testing
Control testing
Final clearance
Radioactive waste
E.ON Kernkraft plans to construct a storage facility
for radioactive waste during the post-shutdown transitional
phase. The facility will be located adjacent to
the Stade site and will be used exclusively to house
radioactive waste from the operation and dismantlement
of the Stade nuclear power station. Only low
and medium-level radioactive waste will be stored
in the facility; the fuel elements will be transported
off-site prior to the start of dismantling work.
The storage facility will have a service life of
40 years, and is intended for temporary storage until
Germany’s federal government provides a final storage
facility. However, the waste will be placed in the
temporary facility in a form suitable for final storage.
11
2
4
5
Elbe River
1
10
8
9
6
3
7
1 Reactor building
2 Reactor auxiliary building
and annexes
3 Aftercooling system building
4 Switchgear building
5 Turbine room
6 Control building
7 Office and employee services
building
8 Workshop and storage area
9 Emergency diesel generating
sets
10 Transformers
11 Planned temporary storage
facility for radioactive waste
27
What happens to the vacant site?
Green fields
In Germany two nuclear power station sites have
already been returned to ‘green fields.’ Broadly
speaking, the land on which the power plants were
once located has been returned to nature: it has
been replanted and is now lying fellow. The Stade
site will also be restored to green fields. At this
stage it has not been decided if and to what extent
the land will be put to other industrial uses.
29
What is the regulatory environment under which
decommissioning is performed?
Statues and regulations
In Germany the construction, operation, and decommissioning
of nuclear power stations is governed by
the Atomic Energy Act (AtG). The decommissioning
and dismantlement of nuclear facilities is also subject
to numerous statutory and administrative regulations.
The regulatory framework includes the Radiation
Protection Regulations (StSV), the Recycling and
Waste Management Act (KrW-/AbfG ), the Hazardous
Substances Regulations (GefStoffV), and the Federal
Pollution Control Act (BimSchG).
The permit process
Permit application
Permitting authority
(highest competent
authority at state level)
Decision
Clearance procedures
Permanent nuclear power station decommissioning
and safe enclosure require permits issued in accordance
with the Atomic Energy Act (AtG) by the highest
competent state-level authority. Accordingly,
E.ON Kernkraft GmbH has applied to Germany’s
Lower Saxony State Ministry for the Environment
for a permit to decommission and dismantle the
Stade nuclear power station.
The diagram above shows the role of the various
government bodies and institutions in the permit
process.
Additional reports
Participating government agencies
General public
Expert report
Federal Ministry for the Environment,
Conservation and Reactor Safety (BMU)
Participating federal
agencies
Environmental impact analysis
An environmental impact analysis must be performed
before the Stade nuclear power station decommissioning
project can proceed. The analysis must cover
all aspects of the project, including the proposed construction
of a temporary storage facility for radioactive
waste from the operation and dismantlement of
the plant. Its purpose is to ascertain and assess the
project’s environmental impacts. The environmental
impact analysis is thus an integral part of the permit
process.
31
Reactor Safety Commission
Radiation Protection Commission
32
The Stade nuclear power station in brief
Stade nuclear power station
Technical data
Reactor type BWR
Net installed capacity 630 MW
Start of commercial on-load operation May 19, 1972
Nuclear plant
Reactor pressure vessel
Rated pressure (positive) 175 bar
Internal diameter 4,080 mm
Overall height 10,400 mm
Cylinder section wall thickness plus plating 192 + 7 mm
Total weight 270 t
Reactor core
Number of fuel elements 157
Total uranium weight 56 t
Number of control rods 49
Steam generators
Number 4
Steam output per unit 898.1 t/h
Output steam pressure 52 bar
Output steam temperature 265 °C
Reactor cooling system
Number of coolant pumps 4
Average coolant temperature 298 °C
Containment
Ball diameter 48 m
Rated pressure (positive) 3.8 bar
Wall thickness 25-35 mm
Turbine room systems
Turbines and condenser
High-pressure turbine 1
Low pressure turbine 2
Speed 1,500 min –1
Heat rise of cooling water in condenser 9 K
Generator
Output 780 MVA
Transformer voltage 21 kV
Power factor (cos phi) 0.85
Unit transformers
Number 2
Output per unit 380 MVA
Frequency 50 Hz
Cogeneration system
Tertiary loop steam volume 60 t/h, corresp. to 7.7 MW
Steam pressure 10 bar
Steam temperature 190°C
Condensate pipeline 1.5 km to salt works
Located on the banks of the Elbe River,
the Stade nuclear power station was commissioned
in 1972. It has been cogenerating
process heat for a neighboring salt
works since 1984.
The Stade plant is two-thirds owned
by E.ON Kernkraft GmbH. The remaining
one-third stake is owned by Vattenfall
Europe AG.
Publisher
E.ON Kernkraft GmbH
Corporate Communications
Tresckowstraße 5
30457 Hannover
Germany
Editor
Kernkraftwerk Stade
Public Relations
Photographs
Peter Hamel
Volkmar Gawehn, Isernhagen (page 2)
Zefa, Hamburg (page 29)
Archivberlin, Berlin (page 30)
Translation
Anglobe Business Services,
Hamburg
Design
Maurer Werbeagentur,
Hannover
Printer
Gesellschaft für Digital- und
Printmedien mbH, Hannover
Edition 6/2004
All rights reserved. No part of
this document may be reproduced
without the Editor’s permission.
E.ON Kernkraft GmbH PO Box 4849 30048 Hannover Germany
Tresckowstraße 5 30457 Hannover Germany
T +49 (0)5 11-4 39 03 F +49 (0)5 11-4 39 23 75
www.eon-kernkraft.com www.eon.com
Stade Nuclear Power Plant Bassenflether Chaussee 21723 Stade Germany
T +49 (0)41 41-77 23 91 F +49 (0)41 41-79 93 04
E.ON Kernkraft GmbH Corporate Communications
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