Brief Description for Dismantling of KKK

Brief Description for Decommissioning and Dismantling of the Krümmel Nuclear Power Plant

May 2018

2 Brief Description for Dismantling of KKK

List of Contents

1. The project “Decommissioning and Dismantling of the Krümmel Nuclear Power Plant“ ________ 3

2. The Krümmel Nuclear Power Plant __________________________________________________ 5

3. Decommissioning and Dismantling _________________________________________________ 10

4. Residual Materials ______________________________________________________________ 16

5. Treatment, Storage and Final Location of the Radioactive Waste _________________________ 19

6. Safety Analysis _________________________________________________________________ 20

7. Radiation Exposure in the Environment _____________________________________________ 22

8. Environmental Impact ___________________________________________________________ 24

GLOSSARY ______________________________________________________________________ 27


1. The project “Decommissioning and Dismantling of the Krümmel Nuclear

Power Plant“ The Krümmel nuclear power plant (KKK) went into commercial operation on 28 March 1984. With a

gross electric capacity of 1402 MW, KKK produced 201,712 GWh electricity while it was operational.

Backfitting of the KKK facility were continuously carried out during the entire operating life, bringing

the facility constantly up to the latest state of science and technology.

The licence for power-producing operation of the Krümmel nuclear power plant became void upon

enforcement of the 13th Amendment to the German Atomic Energy Act (“AtG”) on 06 August 2011.

The Krümmel NPP is to be decommissioned and dismantled.

By letter of 24 August 2015, a supplement to which was filed on 29 September 2017, Kernkraftwerk

Krümmel GmbH & Co. oHG filed the application according to section 7 (3) AtG for decommissioning

and dismantling of the Krümmel nuclear power plant. This application covers decommissioning of the

nuclear power plant, i.e. the final and permanent discontinuation of operations, furthermore the so-

called residual operation phase, and the dismantling of parts of the facility.

By the time the Decommissioning and Dismantling Licence has been granted, the irradiated fuel

assemblies of KKK will, with the exception of some special fuel rods, have been removed and hauled

away from the plant. This will allow for speedy dismantling of the KKK facility as soon as the

Decommissioning and Dismantling Licence is utilised.

The Krümmel nuclear power plant has since 05 November 2014 been in the phase of so-called long-

term shutdown operation, a phase that will last until the Decommissioning and Dismantling Licence

has been granted and is utilised. During such long-term shutdown operation, works in preparation of

subsequent dismantling of the nuclear power plant will take place, including in particular:

Removal of fuel assemblies from the plant

Disposal of operational waste

Decontamination of systems and components no longer required for long-term shutdown

operation

Decommissioning of systems no longer required

Other preparatory works

As soon as the Decommissioning and Dismantling Licence has been granted and utilised, the works to

dismantle the KKK facility will start. After the KKK facility will have been released from nuclear

supervision, conventional works for demolition of the buildings - to the extent these are not

dedicated to some subsequent use - will be performed according to the relevant law governing such

works.

At the beginning of the dismantling works, a few systems like e.g. ventilation systems, utility and

monitoring systems will still be in operation. These are to be modified to match the new

requirements in the course of the dismantling works, or to be replaced by new, adapted systems, the

so-called “Dismantling Infrastructure“.

The dismantling works will require changes in the designated use of relevant rooms/zones. These will

comprise the required changes to be made as well as the creation of back-up and buffer storage


areas and transport routes. This will ensure that all contaminated and activated parts of the KKK

facility can then be dismantled speedily and without any repercussions.

At the beginning of the dismantling works, is also planned to remove the remaining special fuel rods

from the plant in conjunction with the dismantling works.

Most of the radioactive residual materials accumulated during dismantling will be processed in a

residual material processing and waste treatment facility to be newly established on site in the

controlled area of the facility. There, they will be disassembled further, decontaminated, conditioned

and packaged. Generally, the radioactive waste from dismantling works will be brought to a storage

facility for radioactive waste with negligible heat generation and residues (“LasmAZ”: storage facility

for low- and medium-level radioactive waste next to the interim storage facility). The waste will be

stored there until it can be delivered to the final repository of the German Federal government.

The construction and operation of the residual material processing and waste treatment facility are

incorporated in the application for decommissioning and dismantling of KKK. Separate licensing

procedures are conducted for erection and operation of the planned LasmAaZ.

As soon as the KKK plant has been cleared away, the operating premises of the KKK facility will be

available for follow-up uses. The Krümmel on-site interim storage facility and the planned LasmAaZ

will remain in operation according to the valid requirements until all radioactive waste stored there

has been hauled away.


2. The Krümmel Nuclear Power Plant

Description of the plant

The Krümmel nuclear power plant is located in the southeastern part of the German state of

Schleswig-Holstein, approximately 34 km out of Hamburg. The site is located on the northern bank of

the Elbe River and belongs to Krümmel, a part of the town of Geesthacht in the rural district

Herzogtum Lauenburg (Duchy of Lauenburg).

As depicted below, the operating premises are limited on the south-western side, towards the Elbe

River, by Elbuferstrasse, a road running on the Elbe River bank in parallel with the river. The

Krümmelstrasse road runs along the north-western side of the premises. The eastern boundary is

formed by the premises of the Geesthacht Helmholtz Centre. To the east of the plant, another part of

Geesthacht called Grünhof-Tesperhude is situated around 1 km away. On the north-eastern site, the

outdoor switch plant compound is situated adjacent to the site.

Figure 1: Location of the Krümmel nuclear power plant (schematic view)

The heart of the Krümmel nuclear power plant is formed by a boiling-water reactor with a gross

electric capacity of 1,402 MW. The reactor pressure vessel houses 840 fuel assemblies that heat up

as a result of nuclear fission and generate steam. The 205 control rods serve the purpose of starting

and stopping the reactor, and of reactor scram.

The generated main steam is channelled directly to the turbine that drives the generator for power

production. The steam will then be re-liquefied in the condenser and piped back as feed water to the

reactor pressure vessel via the feed water heating system.


Figure 2: Flow chart of the Krümmel nuclear power plant

Buildings and parts of the facility

Access to the supervised area is possible from Elbuferstrasse through the guardhouse with its motor-

vehicle transfer port. The operating premises are also built up with the Krümmel on-site interim

storage facility, the LasmAaZ that has to be newly erected, and - with just a few exceptions - all other

buildings of the facility. The operating premises are surrounded by a solid fence. The guarded area is

enclosed by a fence mounted with intrusion detection.

Figure 3 shows the Krümmel nuclear power plant‘s site map that gives an impression of the compact

siting of the central buildings:

reactor building with water treatment facility,

turbine hall incl. connected storage building,

switchgear building incl. control room, and the

nuclear services buildings.

Apart from these, the operating premises are built up with further buildings and facilities, e.g.:

the cooling water pump houses,

the workshop building, and

the administrative buildings.


Figure 3: Site map of the Krümmel nuclear power plant

The main buildings of the power plant relevant for dismantling are briefly described below.

The reactor building is a reinforced-concrete structure that serves, on the one hand, as a shield and

to retain activity, and on the other, as protection against external impacts. This building houses the

steel containment vessel that is designed to retain activity in the event of an incident. The steel

containment is divided into two spatial compartments, the pressure chamber and the condensation

chamber, which together form the pressure suppression system. The pressure chamber houses the

reactor pressure vessel with important safety-relevant pipelines and safety valves. Next to it, the

treatment section with the water treatment facilities and, on top of these, the exhaust air stack are

located on the south-western front side of the building.

The turbine hall is directly adjacent to the reactor building at the latter’s north-western elevation. It

houses mainly the turbine and generator for power production and the supporting auxiliary systems.


Figure 4: Cross-section of the central buildings of the Krümmel nuclear power plant

The switchgear building is adjacent to the turbine hall / reactor building on the north-eastern side

and contains the facilities and systems for voltage supply, control, monitoring and instrumentation of

the nuclear power plant, e.g. the power plant control room.

The nuclear services building contains offices, laboratories and staff facilities, a storage area and an

access point to the controlled area. Some parts of the building belong to the controlled area. Here,

for example, the hot locker room, laboratories and washing water reservoirs can be found.

The administrative buildings house the office and meeting rooms. Access to the supervised area is

provided through the guardhouse with its motor-vehicle port.

The solids depot and the hot workshop are located at the southeastern elevation of the reactor

building, each being fitted with a transport opening. This building houses the drum refilling unit, the

decontamination box and a storage cellar (incl. drum store and two caverns).

The Krümmel on-site interim storage facility (“SZK”) located in the south-eastern part of the

operating premises is designed to store spent fuel assemblies in casks (so-called CASTOR® casks) until

these are hauled away to the Federal final repository.

After having been packaged and conditioned for storage in the final repository, the dismantling

waste will be transported to a storage facility for radioactive waste with negligible heat generation

and radioactive residues (LasmAaZ) located on the operating premises, and stored there until it is

delivered to a national final repository.


Initial State for Dismantling of the KKK Facility

The baseline condition of the KKK facility at the time the applied-for Decommissioning and

Dismantling Licence is granted will be characterised by the following main features:

There are no fuel assemblies in the plant; possibly, up to 200 special fuel rods will still be

there.

Radioactive materials are no longer newly produced.

The short-lived radionuclides have decayed since the plant was shut down.

No high pressures or temperatures occur in the systems still in operation.

As a result of the decontamination activities performed, much of the contamination of the

systems will have been removed.

The major share of the plant and equipment, systems and components in the controlled area

are not or only slightly contaminated.

Unless the special fuel rods can be hauled away as early as during the phase of long-term shutdown

operation, they will be transferred (total activity approx. 1015 Becquerel) to shipping and storage

casks and put into on-site interim storage upon commencement of the dismantling works. This will

further reduce the activity of the facility.

The activity inventory to be removed during dismantling amounts to approximately 1x1017 Bq. The

vast majority of that comes in the form of activation. The radioactivity is firmly bound mainly in the

materials of the reactor pressure vessel (RPV), the RPV internals and the biological shield, and can

therefore not be mobilised directly. A small fraction of the activity inventory comes in the form of

contamination. It will mostly reside on the internal surfaces of systems.

Pre-existing contamination

The term “pre-existing contamination” denotes the radiation exposure resulting from operation of

other nuclear installations and facilities and potentially contributing to the radiation exposure of the

KKK facility.

Pre-existing contamination must be assumed to be present from the discharge of radioactive

substances via the air and water of the nuclear power plants of Brokdorf, Stade (in the process of

being dismantled), the Geesthacht Helmholtz Centre and the Brunsbüttel nuclear power plant. In

order to assess any potential further pre-existing contamination that may, for instance, have been

caused by hospitals or research institutes, the substitute method used – as recommended by the

Radiation Protection Commission – is to calculate the potential radiation exposure through

radionuclide excretion of nuclear medicine patients.

Existing interim storage facilities are left out of consideration as they do not generate any emissions

via the air or water pathways. The same applies to the collecting facility for radioactive waste of the

Land of Schleswig-Holstein at the Geesthacht Helmholz Centre. The radiation exposure level is

determined on the KKK site and in its immediate vicinity by way of environmental monitoring

programmes pursuant to the Guideline concerning Emission and Immission Monitoring of Nuclear

Installations.


3. Decommissioning and Dismantling

Available experience

Various nuclear facilities have already been decommissioned in Germany. Some of them are in the

state of safe enclosure, and several plants have already been fully dismantled.

The Krümmel nuclear power plant is envisaged to be dismantled continuously without this being

preceded by a period of safe enclosure. This approach offers the following advantages:

Existing systems, facilities, components and auxiliary means can still be dedicated to

meaningful uses at the beginning of the dismantling activities.

A sufficient number of experienced staff with facility-specific know-how is still available.

A considerable number of jobs can be preserved.

It is not necessary to keep personnel in place for later dismantling.

The nuclear power plant can soon be released from supervision under nuclear legislation.

The experience gathered with the deconstruction of other nuclear power plants like

Gundremmingen, Würgassen, Stade and Obrigheim can be applied to the KKK facility. Its dismantling

can, on the basis of the knowledge and experience at hand, be carried out with the existing technical

processes and equipment. The dismantling projects completed and underway have shown that a

nuclear power plant can be dismantled without any risks to members of the public, the environment

and the plant personnel and in compliance with the legal requirements.

Dismantling works at the facility will begin as soon as the Decommissioning and Dismantling Licence

has started to be utilised. The total activities to be performed are intended to be applied for in the

form of at least one licence under the German Atomic Energy Act. After the Krümmel nuclear power

plant has been released from nuclear supervision, the buildings of the KKK facility can be demolished

to the extent they are not dedicated to any follow-up uses.

Dismantling concept

Dismantling of the Krümmel nuclear power plant will comprise the following:

Adaptation of the residual operation systems required to meet the protection objectives and

comply with industrial safety regulations, to the necessities of dismantling; or their

replacement by new systems.

Dismantling of contaminated or activated systems and parts of the facility which are situated

in the controlled and supervised area and are no longer needed.

Decontamination of any remaining parts of the facility.

Residual clearing as well as decontamination and clearance of buildings and, if necessary, of

ground areas, or the removal of such as defined by to the Guide to Decommissioning of the

German Ministry of the Environment, Nature Conservation and Nuclear Safety.

Then release of the KKK facility from nuclear supervision.


The potential conventional demolition of those buildings not dedicated to any follow-up use will be

performed during the phase of demolition of the buildings in compliance with the law applicable to

that.

Principles of dismantling

Planning of the individual dismantling works in the course of the respective dismantling phase will

ensure that

the safety of members of the public and the plant personnel is always ensured,

individual dismantling measures are not mutually aggravating or obstructive,

the radiation exposure of the dismantling staff and the leakage of radioactive substances into

the indoor air are kept down to minimum levels,

the volume of radioactive residual materials and conventional waste is reduced.

During the dismantling works, attention will be paid to ensuring that parts of the facilities that will

still be needed later on are not dismantled too early, and that parts of facilities that obstruct the

dismantling of other parts are dismantled first.

Infrastructure

Performance of the dismantling works presupposes modifications to the infrastructure systems still

present from the phase of power operation, or replacing them by new, temporary substitute systems

to enable dismantling of the original infrastructure. The substitute systems may as well be utility and

monitoring systems erected outside the controlled area. They are tailored to the needs of the

dismantling works and enable optimised execution of all dismantling works at the KKK facility. These

are the key purposes of the Dismantling Infrastructure:

ventilation and aeration of the controlled area;

collection and treatment of effluents from the controlled area;

power supply;

availability of all other infrastructure like fire protection, radiation protection and

communication facilities.

The safety requirements of the Dismantling Infrastructure meet the protection objectives of “limiting

the radiation exposure“ and “safe enclosure of radioactive substances“ still applicable to dismantling

of the KKK facility. As soon as the works to dismantle the parts of the KKK facility have been

completed, this substitute infrastructure will also be decommissioned step by step and then

deconstructed.

Techniques and devices for dismantling

A multitude of well-tried techniques and devices is available for dismantling plant components, and

for disassembling and decontaminating the dismantled parts of the facilities. The optimal technique

for the respective task to be performed will be selected on the basis of the following selection

criteria:

Industrial safety

Radiation exposure of the staff


Containment of activity

Tried and tested application in practice

Production of secondary waste

Efficiency

Space requirements

Logistic and transport requirements

Economic efficiency

Generally speaking, two different approaches may be applied to dismantling contaminated

components:

a) In-situ disassembly and processing of the components

b) Removal of the components as a whole or in part, followed by processing in the residual

material processing and waste treatment facility in the turbine hall or other parts of the

controlled area.

The preferred option will be to remove the components as a whole or pre-disassemble them in part,

so that they can temporarily be made available to processing in the designated back-up storage

areas. In exceptional cases, external processing will be handled on the premises of a service provider.

Activated components will partly be disassembled under water.

At the beginning of the dismantling works, the facility will first be prepared for dismantling. For this

purpose, the infrastructure will be adapted to the requirements of dismantling and processing of

residual materials. Additionally, the logistic basis for dismantling will be created (e.g. transportation

routes, material ports, back-up and buffer storage areas), and the facilities for waste and residual

materials processing, most of which will be located in the turbine hall, will be erected and

commissioned.

In a first step, especially the contaminated parts of the facilities in the turbine hall and reactor

building, and the activated internals of the reactor pressure vessel are to be dismantled.

The utility systems will remain in operation until they are no longer needed, be adapted, replaced by

substitute systems or dismantled. In the course of the dismantling works, the required services will

be provided with the help of a new, temporary infrastructure. This will permit dismantling of the

remaining parts and components of the facility without any repercussions, while, at the same time,

all mandatory safety requirements will be met.

Figure 6 shows a schematic view of the main components in the reactor building. Here, the upper

part of the containment as well as the closure head of the pressure vessel will be removed first.

Furthermore,

pipelines with their fittings, consoles and brackets,

heat exchangers and pumps,

the refuelling machine,

the shielding slabs and

the venting tank

will be dismantled.


Figure 6: Reactor building – schematic view showing the main components

The internals of the reactor pressure vessel will be dismantled and disassembled in the reactor

building. Where necessary on grounds of radiation protection, this will be done under water. The

activated parts will be packaged directly in approved final-repository casks there, and put into

interim storage in a LasmAaZ until they can be delivered to the final repository of the Federal

government.


Furthermore, the shell of the reactor pressure vessel, the bottom section, the well of the

containment and the biological shield will be dismantled. The pipelines and parts of the remaining

systems like the ventilation system will be disassembled except for the needed infrastructure.

Disassembly of the reactor pressure vessel can be approached in different ways. Preferably, a

preliminary disassembly is performed in the fitting position, and post-disassembly in a post-

disassembly area. The disassembled parts will, depending on the degree of activation, either be

packaged in situ ready for transport to the final repository and transported to a LasmAaZ, or

transported in containers for further treatment to the residual material processing and waste

treatment facility respectively to back-up storage areas set up in the controlled area.

Dismantling of the biological shield can be performed by preliminary disassembly into transportable

segments, followed by post-disassembly in another suitable place in the controlled area of the

facility, or in the residual material processing and waste treatment facility. Post-disassembly and

conditioning may as well be handled on the premises of an external service provider. As a potential

alternative, full disassembly of the biological shield in its fitting position is conceivable.

In parallel with the dismantling works in the reactor building, it is planned to begin with dismantling

large-scale components in the turbine hall: for example the turbine, the condenser, the moisture

separator reheaters, the feed water tank and further heat exchangers. Equally, pipelines, pumps and

fittings are to be dismounted. Further dismantling works will take place at all levels of the turbine

hall. The remaining pipelines and parts will be preferably dismantled room by room. Furthermore,

withdrawal from the rooms of the controlled area will be progressed. Full dismantling of the

components in the turbine hall will be completed upon residual clearing of the facility.

Dismantling works are also envisaged to be performed in the supervised area.

In the further course of dismantling works, all remaining dismantling works will be performed which

have yet to be carried out until the radioactive substances have been removed and disposed of from

the buildings and the supervised area of the KKK facility. In particular, this includes

the decontamination of installations remaining in the buildings, and of the building

structures in the controlled area,

dismantling of all remaining contaminated and/or activated parts of the facility,

dismantling of the remaining infrastructure,

residual clearing of the facility and

clearance / removal of the remaining internals, building structures and, if appropriate,

ground areas of the operating premises according to section 29 Radiation Protection

Ordinance.

Release from supervision under the Atomic Energy Act is envisaged at the latest after the withdrawal

steps have been completed.


Decomposition products

The majority of parts of facilities envisaged for dismantling will merely exhibit low-level

contamination due to the operating history. The contaminated parts of the facilities will be

dismantled manually in situ, with the help of techniques and devices tried and tested in the industry.

The dismantled parts of facilities will be brought for processing, i.e. for disassembly, decontamination

and clearance measurements, into the residual material processing and waste treatment facility. At

any time during dismantling of the facility, clearance measurements can be carried out on non-

contaminated or non-activated parts of the facility such that these can then, as non-radioactive

substances, be released from the scope of applicability of the Atomic Energy Act, and removed and

transferred, respectively, in compliance with the stipulations of the Radiation Protection Ordinance.

Many of the parts of the facility can be re-integrated into the conventional substance cycle. The

radioactive waste occasioned during processing will be put into interim storage in the planned

storage facility for radioactive waste with negligible heat generation and radioactive residues

(LasmAaZ) until it is delivered to the national final repository.

Time schedule

Long-term shutdown operation or post-shutdown operation will end at the latest upon granting and

utilisation of the Decommissioning and Dismantling Licence, which is expected to be the case in

2020. The dismantling works to be performed during the so-called residual operation of the plant will

prospectively take up to 15 years. Another two to three years will go by until the buildings will have

been finally demolished.

The Krümmel on-site interim storage facility and the planned storage facility for radioactive waste

with negligible heat generation and radioactive residues may continue to be operated at the site

according to the regulations applicable from time to time.


4. Residual Materials

Description of the residual materials

The KKK facility has an overall mass of around 541,000 Mg, the vast majority of which is accounted

for by buildings and installations outside the controlled area. The majority of the residual materials

from dismantling of plant parts are neither contaminated nor activated. These materials can be

returned to the scope of applicability of the Closed Substance Cycle and Waste Management Act, or

passed on to third parties, without any formal notice of clearance according to section 29 of the

Radiation Protection Ordinance.

Similarly, most of the buildings and installations of the controlled area can be graded non-

radioactive, where necessary following decontamination. A large part of the radioactive residual

materials from the dismantling processes can be released following application of suitable processing

techniques

in the KKK facility (e.g. decontamination by wiping) or

in the residual materials and waste treatment facility (e.g. decontamination with the help of

high-pressure blasting).

About 1% by weight of all dismantled plant components of KKK will be subject to clearance for

disposal. Only another approx. 1.5% of the dismantled parts of facilities will prospectively have to be

graded as radioactive waste and transported to a government-owned final repository in a controlled

way (Figure 7).

Figure 7: Percentage breakdown of the overall mass of the Krümmel nuclear power plant

Measures taken to avoid radioactive residual materials

When dismantling the KKK facility, the ambition will be to avoid that additional radioactive residual

materials are produced. This will be achieved, among other things, by selecting suitable installations


and devices to perform the dismantling works, and by avoiding that unnecessary materials like

packaging are taken to the controlled area.

Measures taken to reduce radioactive waste

Another ambition in dismantling will be to keep the volume of additional radioactive waste down as

much as possible. The following measures can be taken both to avoid and to reduce the volume of

radioactive waste:

When dismantling and disassembling activated and contaminated parts of facilities,

techniques ensuring the lowest possible release of radioactivity will be used.

While the dismantling works are performed, the different residual materials will be collected

in a targeted manner at the place where they originate.

Contaminated parts of facilities are decontaminated wherever this is meaningful in order to

then have them released, if possible, according to section 29 of the Radiation Protection

Ordinance.

The volume of waste accumulated will be reduced by the application of tried and tested

methods of radioactive waste treatment.

Removal of contamination-free substances, movables, buildings, soil areas, facilities and parts of

facilities

Substances, movables, buildings, soil areas, facilities and parts of facilities contamination of which

can be ruled out can be returned to the conventional substance cycle without any formal notice of

clearance according to section 29 of the Radiation Protection Ordinance, or passed on to third

parties, after undergoing a selection and testing procedure.

In the scope of the selection procedure, it will be reviewed whether the following criteria have been

met:

The substances, movables, facilities and parts of facilities were at no time inside the

controlled area. Buildings and floor space were at no time part of a controlled area where

open radioactive substances were handled.

Activation can be excluded with certainty.

Contamination can be excluded with certainty in view of the operating history.

In the ensuing testing procedure, plausibility considerations and control surveys (random samples)

will be made to secure evidence.

Processing of radioactive residual materials

The radioactive residual materials from dismantling will generally be processed in the residual

material processing and waste treatment facility. Some of the radioactive residual materials can be

decontaminated and forwarded for clearance with the installations available at the KKK facility.

Processing may as well be handled at external sites.


Clearance procedure

The clearance of radioactive residual materials, buildings and soil areas is granted in a specific notice

according to section 29 Radiation Protection Ordinance, issued by the Schleswig-Holstein prudential

and approval authority under nuclear legislation. This notice will set out the approach to be used in

detail. Radioactive residual materials from dismantling will be transported to the residual material

processing and waste treatment facility for processing and clearance measurements with clearance

measuring instruments.

Parts of facilities measured and released directly in the KKK facility will be hauled away from KKK as

soon as clearance has been established. The buildings of the controlled area will be cleared as soon

as the decontamination works have been completed.


5. Treatment, Storage and Final Location of the Radioactive Waste

General

Dismantling of the KKK facility is expected to generate up to 8,000 Mg of radioactive waste. As it is

currently not foreseeable when the Federal final repository will be available, a storage facility for

radioactive waste with negligible heat generation and radioactive residues (LasmAaZ) is planned to

be commissioned on the site.

Tried and tested standard methods will be used to treat the radioactive waste of KKK and in the

residual material and waste treatment facilities. These include inter-alia supercompaction and

drying.

Combustible radioactive waste will be treated off-site. In exceptional cases, the radioactive residual

materials will only be processed to a level where mid- to long-term interim storage is possible, or the

radioactive waste can later be conditioned into the then required form suitable for final storage

without requiring a major effort.

For temporary storage of unconditioned or partly treated waste before or during waste treatment,

back-up storage areas will be set up.

The resulting waste products will be packaged in waste containers. For example, qualified steel plate

containers and cast iron containers will be used as waste containers.

During processing and packaging of the radioactive waste, quality assurance measures will be taken

to guarantee compliance with the predefined safety requirements with regard to the resulting waste

packaging units. The radioactive waste and the radioactive residual materials will be continuously

recorded and documented according to their respective condition.

Besides the back-up and buffer storage areas, dismantling of KKK will require temporary storage

space. Such storage space can be accommodated in the supervised area and on the operating

premises. This storage space can be used for non-radioactive as well as measured and cleared

residual materials. The storage space within the operating premises can only be used for non-

radioactive as well as cleared residual materials .

Storage facility for radioactive waste with negligible heat generation and radioactive residues

(LasmAaZ)

The planned storage facility for radioactive waste with negligible heat generation and radioactive

residues is designed for interim storage of the radioactive waste and residues originating from the

dismantling process of the KKK facility. The planned storage capacity has been sufficiently sized to

take care of the operational waste and the total radioactive waste expected to be accumulated

during dismantling of the facility.


6. Safety Analysis

At the beginning of the dismantling works, the fuel assemblies will have been eliminated from the

plant. There may possibly be up to 200 special fuel rods left in the facility which do not require the

use of any systems for residual heat removal. At that time, the activity potential will already have

been reduced by approximately 99% in comparison with power operation.

In order to judge the sufficiency of precautions taken against the impact of incidents, postulated

sequences of events potentially occurring during dismantling and relevant for safety were analysed in

consideration of the “Guide to the decommissioning, the safe enclosure and the dismantling of

facilities or parts thereof as defined in section 7 of the Atomic Energy Act“, the “Recommendations of

the Nuclear Waste Management Commission (Guide to the decommissioning of nuclear facilities)“,

and of the safety requirements the nuclear power plants. Accordingly, the following events must be

taken into account for residual operation of the facility:

Internal impacts:

Internal fire

Leakage of vessels

Internal flooding in the facility

Breakdown of components

Crashing of loads

Events occurring during transport operations

Interaction with other facilities at the site

Internal explosions in the facility

Chemical impacts

Outage of systems and equipment relevant for safety

External impacts:

a) Impacts caused by nature, e.g.:

Extreme meteorological conditions

Flooding

Biological impacts

Forest fire

Earthquake

b) External impacts caused by civilisation, e.g.:

Plane crash

Explosion external to the facility

Penetration of dangerous substances


External fire

If the facility still contains special fuel rods during the decommissioning procedure, the following

event will be relevant in addition:

Events during handling and storage of special fuel rods.

In order to investigate the consequences of an incident, events important for safety were analysed.

Crashing of a storage drum containing filter concentrates during handling or packaging in the solids

depot in the reactor building was identified as a covering event in view of its radiological

consequences in the environment. The potential radiation exposure in the environment determined

on the basis of conservative assumptions may amount to approximately max 0.7 mSv for the age

group with the highest exposure to radiation in this case. The dose calculated for this event

undercuts the limit value of 50 mSv by far. The radiation exposure of all other courses of events

under analysis undercuts this threshold even more markedly.

In the case of the events “Outages and malfunctions of installations relevant for safety “, “Crashing of

loads“, “Internal fire“ and “Internal flooding“, no impermissible radiological impact on the

environment needs to be anticipated. Additionally, the KKK facility is designed to withstand natural

external impacts like wind, external fire, lightning strike and flooding. For events caused by

civilisation, it has been shown that the emergency reference levels of civil protection are not

reached. Protection against impacts caused by third parties like sabotage has been ensured by way of

the requisite constructional and organisational precautions.

In summary, it can be established that the sequences of events that have to be investigated

according to the requirements suggest, if anything, radiation exposures in the environment which are

by more than one magnitude below the incident planning reference level of the Radiation Protection

Ordinance. None of the potential sequences of events analysed for residual operation and

dismantling of KKK is expected to cause any radiation exposure in the environment which would

come anywhere near the incident planning reference level of 50 mSv. This means the demands set

out in the Radiation Protection Ordinance for the purpose of limiting the radiation exposure resulting

from incidents during dismantling of the KKK facility are being met, and the legally stipulated

maximum levels of radiation exposure for dismantling of the KKK facility are distinctly undercut in

any given case.


7. Radiation Exposure in the Environment

Protection objectives

After the fuel assemblies and special fuel rods will have been hauled away according to nuclear rules

and standards, the remaining protection objectives of

“safe enclosure of radioactive substances” and

“limiting the radiation exposure”

have to be fulfilled for dismantling of the KKK facility.

This will be ensured by way of the current infrastructure and the Dismantling Infrastructure, and by

the planned way of execution of the dismantling works. For example, the following precautions will

be taken:

The ventilation systems will create a pressure below the outdoor atmospheric pressure in the

buildings of the controlled area. This way, a directed airflow for filtering of the indoor air is

always ensured.

The activity of the indoor air and the filter systems of the exhaust air stack are continuously

monitored.

At risk of increased activity releases into the indoor air, enclosures with mobile filter systems

will additionally be used.

Upon grave disturbances of operational workflows, the dismantling works will be

discontinued.

Any release of radioactive substances in water which would exceed the limit values will be

prevented by measurements.

The sampling activities, radiological data volumes, measures for the preservation of evidence

and documentation of the measured values are designed such that any discharge of

radioactive substances with water and air can be evidenced and traced back completely.

Application values for discharge of radioactive substances

Dismantling of plant parts may cause the release of radioactive substances into the indoor air inside

the KKK facility. These will be retained in the KKK facility to the greatest possible extent as a result of

numerous precautionary measures. A small percentage of the radioactive substances must, despite

the effective methods of retention for radioactivity, be discharged in a controlled way along

pathways designated for this purpose.

The following levels for the discharge of radioactive substances have been applied for in view of

dismantling:

Levels for permissible airborne discharges via the plant exhaust air stack:

Radioactive Gases Total release per annum 4.5 x 1013 Becquerel Release over six months 2.3 x 1013 Becquerel


Radioactive aerosols Total release per annum 1.5 x 1010 Becquerel Release in 180 consecutive days 7.4 x 1009 Becquerel Release on one day 1.5 x 1008 Becquerel

These discharge levels may be adjusted during residual operation as a consequence of changing

boundary conditions. This might, for example, be the case when the existing ventilation system is

replaced by a new, temporary ventilation system with a new exhaust air stack.

Levels for permissible effluent-borne discharges into the River Elbe:

The levels for effluent-borne discharges will be adjusted to match the stipulations stated in the

permit under water law applicable from time to time.

Radiological impact of discharges of radioactive substances

The radiation exposure in the environment is always calculated for the most unfavourable receiving

point. The most unfavourable receiving point is a point in the environs where the highest radiation

exposure for a reference person has to be expected due to the distribution of the discharged

radioactive substances in the environment, in consideration of real situations of use like staying and

ingestion of food produced there.

For discharges of radioactive substances with the exhaust air from the KKK facility, the highest

effective dose on site is approximately 0.058 mSv in a given calendar year for the age group with the

highest exposure at the most unfavourable receiving point. Of this total, approximately 0.0479 mSv is

accounted for by emissions caused by interim storage in the planned LasmAaZ.

For discharges borne by effluents, the maximum effective dose is approximately 0.141 mSv p.a. for

the most affected age group. In determining this figure, pre-existing contamination at the site of the

facility has been taken into account.

Each of the calculated dose levels is way below the limit of 0.3 mSv p.a. for the effective dose

according to section 47 Radiation Protection Ordinance. For the sake of comparison: the natural

radiation exposure in Germany is at about 2.1 mSv p.a.

Direct radiation of the environment results from handling of radioactive residual materials in the

residual material processing and waste treatment facility, in the rooms of the controlled area of the

KKK facility, and from transport and buffer storage of radioactive residual materials as well as

measured but not yet cleared residual materials in the controlled area, furthermore from a LasmAaZ

and the on-site interim storage facility.

As a function of the activities that have to be carried out, this radiation will vary in time and place

during dismantling of plant components. The most unfavourable receiving point for direct radiation is

on the perimeter of the operating premises. Appropriate measures like shielding will make sure the

direct radiation remains below the levels defined by the Radiation Protection Ordinance at any point

at the boundary of the plant premises.

The total radiation exposure from discharge with exhaust air, effluents and from direct radiation falls

short of the limit of 1 mSv p.a. for the effective dose as defined in section 46 Radiation Protection


Ordinance. In consideration of the distance to the closest inhabited settlements and the actual

periods of time spent by persons close to the operating premises, the actual radiation exposure is

much lower than the calculated dose levels.

8. Environmental Impact

Before the Decommissioning and Dismantling Licence according to section 7 (3) of the Atomic Energy

Act is granted, an environmental impact assessment must be carried out for the entire project of

“Decommissioning and Dismantling of the Krümmel Nuclear Power Plant“.

The environmental impact assessment is based on an environmental impact analysis that was carried

out on behalf of KKK. The EIA comprises the determination, description and assessment of the

project’s impacts on the assets to be protected which are relevant for examining the preconditions

for granting the licence:

human beings, including human health

fauna, flora and biodiversity

soil, water, air, climate and landscape

cultural and other material assets, and

the interactions between the above-mentioned assets.

Aiming at a holistic analysis, the EIA also covered the impact of other projects (e. g. the erection of a

LasmAaZ) related directly to decommissioning and dismantling of KKK.

On the whole, these steps are meant to ensure that effective environmental precautions have been

taken according to the Act on Environmental Impact Assessments. The outcomes of the

environmental impact analysis for the project are summarised below.

Human beings, including human health, fauna, flora and biodiversity

The air- and water-borne discharge of radioactive substances will lead to radiation exposures

distinctly below the 0.3 mSv p.a. limit of the Radiation Protection Ordinance, even after taking into

account the pre-existing contamination in the vicinity and at greater distance. The limit of 1 mSv per

calendar year applicable to members of the public will be undercut even if direct radiation (including

the LasmAaZ and buffer storage) is included.

The investigation of potential events that might lead to mobilisation of radioactive substances into

the environment led to the conclusion that the incident planning reference level of 50 mSv defined in

the Radiation Protection Ordinance is undercut by far in all events.

The lion's share of dismantling works will be carried out inside the buildings. Internal transport and

loading of materials will lead to transport movements on the roads of the operating premises of the

KKK facility, usually at daytime. It is assumed that the noise and air pollution situation in the environs

of the KKK facility will not change materially as a result of the dismantling works on the site and the

traffic caused by the project, including in the public circulation space.


Light emissions are not expected to be caused by the project as lighting at the KKK site will hardly

change versus the status during power operation of the plant. Relevant heat emissions will not occur

during residual operation and dismantling of the KKK facility.

Fauna, flora and biodiversity

There will be no sealing of surfaces, except at a very reduced scale for the buffer storage areas. The

grounds to be utilised exhibit a merely low sensitivity and conservation value, and have already been

subject to high internal intensities of use. The site does not include any areas designated as a nature

reserve, landscape conservation area or Natura 2000 area.

Mapping exercises were carried out for the species groups of birds, bats and reptiles. Species found

on the operating premises mainly include bird species nesting on buildings and little sensitive to

disturbances, and one bat roost. Avoidance measures are being taken for the bird and bat species in

order to preclude any harmful impacts relevant under species protection law which might result from

the construction works.

The sound emissions will not cause any material disturbance of animals. Also, the abstraction and re-

discharge of Elbe River water for cooling purposes, and the discharge of effluents from the effluent

treatment unit, will not entail any deterioration of the aquatic fauna and flora.

Taking into account all avoidance and mitigation measures, the project will not cause any material

disbeneficial environmental impacts on the environmental assets animals, plants and biodiversity.

Soil

Surfaces will only be sealed to a minor extent. This concerns soils with settlement-specific biotope

types with a limited presence of natural soil functions. No compensatory measures are necessary.

Considerable and adverse impacts on soil as an environmental asset from an exposure to radiation

can be ruled out. The limit values defined in the Radiation Protection Ordinance will be respected

and warrant sufficient protection for the soil resource.

Adverse impacts of the project in the form of soil impairments by way of intrusion of air pollutants

can also be ruled out.

Water

The discharge levels approved with regard to type and volume of effluents and pollutant

concentrations and loads according to the permit under water law will also be complied with, or

even undercut, during dismantling. Impacts on the discharge of conventional sewage into the river

Elbe are not to be expected as the current situation will not deteriorate.

Potential effects of the project on the groundwater situation as a result of sealing of land will be of

minor importance as any precipitation will be returned to the natural water cycle.


Air

Decommissioning and dismantling of the KKK facility will not have any material adverse impact on air

as an environmental asset. Aerosol emissions in the controlled and supervised areas of the facility

will largely be captured by way of enclosures and vacuuming. Dismantling activities on the operating

premises, the operation of the auxiliary boiler units, the function tests of the standby diesel

generators, and the inbound delivery and outbound haulage traffic will not entail any pollution

additional to the current situation.

Climate

The buffer storage areas to be set up will cause a minor alteration of the sealed acreage on the site.

Adverse impacts on the climate as a result of changes to climatic conditions can be ruled out.

Landscape, culture and other material assets

No appreciable adverse impacts on the recreation function of the landscape and / or areas

designated for recreation or leisure uses, or on cultural monuments, memorial sites or land

developed and cultivated by man are to be expected.

Interactions

Interactions between the environmental assets to be protected were considered in the

environmental impact analysis. No interactions of the environmental assets under review here were

recognisable.

Furthermore, project-related considerable impairments of environmental assets which might

noticeably detract from the ecosystem‘s efficiency and functionality can be ruled out as well. On the

whole, it is not to be expected that the project will have any adverse impact on the environment.

This means that no case of interference with nature and landscape pursuant to the German Federal

Nature Conservation Act is constituted.

Procedural Alternatives

Following detailed consideration of all boundary conditions, the proprietor of the KKK facility decided

in favour of the option of immediate dismantling versus the alternative of safe enclosure. The

benefits of immediate dismantling consist, in particular, of a distinctly shorter duration of the project

and the fact that the plant-specific knowledge of the KKK employees can be used.

From an environmental perspective, it is not necessary to specify in detail any technical alternatives

in terms of disassembly, decontamination and conditioning methods as methods tried and tested in

the industry are applied, and, as a matter of principle, there is no qualitative difference in terms of

environmental impacts.


GLOSSARY

Activation Process during which a material becomes radioactive as it is bombarded with neutrons, protons or other particles.

Activity Number of atomic nuclei decaying in a radioactive substance per second. The dimension used is the Becquerel (Bq).

Back-up storage area Storage area at KKK for materials that cannot immediately be transported onwards to the next work area. These areas are located at suitable places in the controlled area.

Buffer storage area A buffer storage area serves the purpose of buffer storage. Buffer storage refers to temporary storage of residual materials before, or during, residual material processing.

Clearance Administrative act causing the release of radioactive substances and movable property, buildings, soil surfaces, facilities or parts of facilities activated or contaminated with radioactive substances from the regulatory scope of the Atomic Energy Act and any ordinances having the force of law based on the latter.

Clearance measurement Activity measurement the result of which permits a decision on clearance of the material by way of comparison with the clearance levels defined in the Radiation Protection Ordinance.

Contamination Contamination with radioactive substances.

Controlled area Area where persons may receive an effective dose of over 6 mSv, or organ doses above 45 mSv for the eye lens or 150 mSv for the skin, hands, forearms, feet and ankles, in a calendar year.

Decommissioning In a wider sense, generic term for all activities geared to decommissioning, including safe enclosure and dismantling. This is in line with technical and international linguistic usage.

Decontamination Removal or reduction of contamination.

Discharge Release of liquid, aerosol-bound or gaseous radioactive substances from the KKK facility and installations, using pathways envisaged for this purpose.

Dose, effective Sum of weighted organ doses in tissues or organs of the body as a result of external or internal radiation exposure.

Emissions The air pollution, noise, vibrations, light, heat, radiation and similar phenomena emanating from a facility.

Interim storage Storage of radioactive waste for an extended period of time until it is hauled away to the final repository.

LasmAaZ Separate structure at the KKK where radioactive waste with negligible heat generation can be put into interim storage until it is hauled away to the Federal final repository. This structure is to be built next to the Krümmel on-site interim storage facility (which is why it is called LasmAaZ in German, “aZ” meaning it is located next to the on-site interim storage facility).

Long-term shutdown Long-term shutdown operation denotes the period of shutdown


operation operation until the point in time post-operation, or utilisation of the first executable licence according to section 7 (3) Atomic Energy Act, is declared by the operator of the KKK facility.

Nuclide A nuclide is a type of atom characterised by its number of protons and its number of neutrons.

On-site interim storage facility

Storage building for dry interim storage of casks loaded with spent fuel assemblies on the site of a nuclear power plant.

Operational waste All radioactive residual materials and waste produced during power operation and long-term shutdown operation, and the operating media, resources and tools which were needed for power operation.

Radiation (radioactive) Propagation of electromagnetic waves (e.g. gamma radiation) or material particles (e.g. alpha particles, beta particles, neutrons) through matter or the unobstructed space.

Radiation exposure Impact of ionising radiation on the human body.

Radiological environmental monitoring

Measurements in the environs of the facility to assess the radiation exposure resulting from discharges of radioactive substances with exhaust air and effluents and from direct radiation, and to check the compliance with maximum permissible activity discharges and dose limits.

Immissions The air pollutants, noise, vibrations, light, heat, radiation and similar environmental impacts affecting human beings, animals and plants, soil, water, the atmosphere as well as cultural assets and other material assets.

Processing Disassembly, sorting, collection, temporary storage and decontamination of radioactive residual materials, and activity measurements on radioactive residual materials.

Protection objective Fundamental technical and radiological safety function with several sub-functions which must be guaranteed to ensure compliance with the respective verification objective and verification criterion.

Radioactivity Property of certain substances of transforming without any external influence and thereby emitting characteristic radiation.

Radioactive substances Substances containing a radionuclide or a mix of several radionuclides, the activity or specific activity of which must not be disregarded in connection with nuclear energy, or radiation protection according to the regulations of the Atomic Energy Act, or an ordinance having the force of law and decreed on the basis of the Atomic Energy Act.

Radionuclide Unstable nuclide decaying spontaneously, without any external influence, with the emission of radiation.

Residual materials, non-radioactive

Substances, movable property, facilities and parts of facilities originating from decommissioning and dismantling processes which are neither contaminated nor activated.

Residual materials, radioactive

Substances, movable property, facilities and parts of facilities originating from decommissioning and dismantling processes which are contaminated or activated and are either dedicated to harmless reuses or disposed of in a controlled way as radioactive waste.


Residual operation Operation of all supply, safety and auxiliary systems necessary for decommissioning, and operation of the facilities necessary for dismantling components, systems and buildings after the decommissioning licence was received.

Secondary waste Radioactive waste generated during residual operation and dismantling due to materials additionally introduced to the KKK facility.

Supervised area Area not forming part of the controlled area where persons may receive an effective dose of over 1 mSv, or organ doses above 15 mSv for the eye lens or 50 mSv for the skin, hands, forearms, feet and ankles, in a calendar year.

Treatment Processing of radioactive waste into waste products (e.g. by way of compaction, solidification, vitrifying, drying) and packaging of the waste products.

Waste, radioactive Radioactive residual materials that have to be disposed of in a controlled way according to the provisions of the Atomic Energy Act.

Waste product Processed radioactive waste without packaging and cask.


Vattenfall Europe Nuclear Energy GmbH

Kernkraftwerk Krümmel

Elbuferstr. 82

21502 Geesthacht

www.vattenfall.de/kernkraft

www.perspektive-kruemmel.de

http://www.vattenfall.de/kernkraft

http://www.perspektive-kruemmel.de/

Brief Description for Dismantling of KKK

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