Post on 06-Aug-2018
Decommissioning of Nuclear
Power Plants –
what are the challenges?
Magnus Oskarsson
BU Nuclear Decommissioning
2016-02-04
SNEC
2
Outline
• Nuclear Operations within Vattenfall
• Nuclear Decommissioning in Sweden:
• Decommissioning planning
• Ringhals 1 & 2
• Strategy
• Challenges
RinghalsForsmark
Nuclear operation within Vattenfall
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BA Generation
BU HydroBU Hydro Power Plants Germany
BU Services Nordic
BU Nuclear Generation
BU SKBBU Nuclear
DecommissioningBU Nuclear Fuel BU KSU
BU Projects & Services
Human Resources Fleet Development
Business Control
Forsmark
Ringhals
Decommissioning Sweden
SVAFO
Decommissioning Germany
SKB
Vattenfall – Nuclear Operations in Sweden
Vattenfall is the majority owner of:
• Forsmark Kraftgrupp AB
• Ringhals AB
• SKB (Swedish Nuclear Fuel and Waste Management Co)
- the final repository for operational waste (SFR)
- the interim storage for spent fuel (CLAB)
• SVAFO
- nuclear license for the R2/R2-0 research reactor
- applied to take over the nuclear license for
Ågesta former NPP (PHWR)
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BWR
PWR
Other Forsmark
Ringhals
Barsebäck
Oskarshamn
SVENSK KÄRNBRÄNSLEHANTERING
Managing decommissioning waste
Free release
Landfill at NPP for
VLLW (optional)
NPP
Conventional
waste, ~ 95%
On site backfilling,
1m below ground
Interim storage and
Encapsulation plant
for spent fuel (Clink) Final repository for
spent fuel
SFL, Final
repository for
long-lived waste
SFR, Final repository short-lived waste
Interim storage long-lived waste
External
treatment
of LILW
e.g. Studsvik
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20302020 2040 20452015 2025 2035
Planned end of operation - start of decommissioning
SVAFO
R2/R2-0
Ringhals 2
Ringhals 1
Ågesta
Barsebäck 1 & 2 Forsmark 1
Forsmark 2
Ringhals 3
Ringhals 4
Forsmark 3
Oskarshamn 3
Oskarshamn 1
Oskarshamn 2
Facilities at SVAFO
Legacy waste handling
Nuclear decommissioning in Sweden
• According to the Act on Nuclear Activities, the licensee is responsible for the
decommissioning of nuclear facilities, such as
- Establish a decommissioning plan
- Estimate the decommissioning cost (sv. Plankalkyl)
based on the Site studies
• SKB have long experience of radioactive waste management, interim storage of
spent fuel and of final disposal of operational waste in Sweden
- An application for extension of the final repository for low and intermediate
level waste (decommissioning waste) has been handed in
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Decommissioning planning within Vattenfall
Separate decommissioning from operation
- operation prioritised before decommissioning
-> separation to keep focus on decommissioning.
- Decommissioning should be viewed as an industrial process with adjusted
authority demands.
Decommissioning knowledge and skills concentrated in a
decommissioning organisation.
- The organisation will be an ”intelligent client”.
- The competence built within a decommissioning organisation will be of use for
the whole Vattenfall group.
Vattenfall is developing decommissioning knowledge and experiences,
both through actual decommissioning projects (SVAFO) and through
further studies and international benchmark.
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Ringhals – Decommissioning of R1 and R2
Planning
Operation of R1 and R2
R1 Shutdown
20202019 2021 2022201820172016
R2 shutdown
PlanningAnalysis
Decommissioning project
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RAB holds the nuclear licensee
Fuel removed
Vattenfall decommissioning
company holds the nuclear
licensee
Decommissioning R2
Decommissioning R1
Estimated time scale
Separation of R1/R2 from R3/R4
Infrastructure - separation of R1/R2 from R3/R4
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Today: Operation of R1/R2/R3/R4
• one integrated site sharing some functions/buildings
(such as waste treatment, physical protection etc)
Tomorrow, new demands on the site:
• Ongoing operation of R3/R4
• Decommissioning of R1/R2
Project organisation – Decommissioning Ringhals 1 & 2
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Project manager
Engineering
Project Scope
Reference concept
RadWaste
Transport
Logistics
CAD
Communication
External
Internal
Legal
Safety & Radiation protection
Physical protection
Radiological characterisation
Reference groupAdministration
Controller
Planning
Risk management
Procurement
Planning – phases in the project (example)
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20202019 2021 2022201820172016 2023 2024 2025 2026 2027 2028 2029
Phase I
Phase II
Phase
III
Planning
Contract
Closing
Contract
Closing
Planning
Planning
Planning
Closing
Contract
Contract
ClosingClosing
Estimated cost for decommissioning of Ringhals 1 & 2
- Ringhals site study 2013 estimated the cost for
decommissioning of R1/R2 to 4-5 Billion SEK
• Site studies are done every third years, by the Nuclear licensees
- an assessment of the decommissioning cost
- Based on the estimated decommissioning cost (“Plankalkyl”) the
authority (SSM) propose the fee to be paid to the Nuclear Waste Fund
• Current fee 4 öre/kWh
• proposed to increase due to different reasons, such as earlier
decommissioning start
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19
Strategy
• Safe
• Cost effective Decommissioning
• Optimised
• Use well known methods and techniques for the
decommissioning and demolition
ALARA BAT Cost
Strategic issues
• Final repository for decommissioning waste (expanded SFR 2028)
• Temporary storage and waste conditioning facilities;
- final repository for long-lived waste planned to be in operation in the
2040s
• Develop an industry guideline for free release of decommissioning waste
• Changing and developing regulatory framework
• Logistics (O1/O2, B1/2, R1/R2 and Ågesta <-> 1 ship “Sigrid” and limited
number of transport casks etc)
• Luck of competence and experienced staff (retirements)
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22
A typical Nuclear Power Plant:
• 1500 rooms in 20-30 isolated structures/buildings
• Tall buildings with multiple basement floors, demands both vertical and
horizontal material movement and people flow.
• Constructed of 200 000 m3 reinforced concrete.
• More than 100 km pipes and tubes, and >100 000 components
• Building area of about 500 000 to 1 000 000 m2
• The access to the site is restricted, the buildings are divided into subs
without physical interconnection
• The Decommissioning & Demolition should take place while electricity
production is ongoing on the site.
• How to get optimised logistics?
Challenge: Optimised Logistics
Challange: Radwaste handling
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Where and when should the radwaste be handled and
temporarily stored/buffered?
New waste management culture.
• Long- and short-lived waste could be stored temporarily on site
• Short-lived waste could be end-conditioned on site
• Where long-lived waste is end-conditioned determined later
Argument for handling and temporarily stored/buffered at Ringhals:
• Non-conditioned waste is bulky to transport
• Space for buffering are available at Ringhals
• Experience and capacity to manage waste at Ringhals
Challenge: Large components
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What strategic aspects is the choice between
segmenting or directly deposited Reactor
Pressure Vessels (RPV)?
• The ability to deposit these components are
strategically important for an effective resolution:
• Reactor pressure vessel including internal
parts (BWRs and PWRs), Steam generators
(BWRs)
Arguments for direct depositing of RPV:
• Higher flexibility
• Segmentation is time consuming
• Simplified management provides significantly
lower dose
Segmented or whole RPV deposited?
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Concreate and steel that are free released can be recycled and used for
other application.
(i.e material with zero or very low radioactivity)
• Public acceptance
• Acceptance by the community
• Acceptance by companies (such as recycling of metals)
Example: Use the concrete as filling material in road constructions
How should acceptance by the stakeholders be achieved?
Challenge: Deposition of free released material
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• There is a need to build-up competence/resources within the
decommissioning area (sub-contractors with high competence)
• Nordic experience from decommissioning is related to small facilities.
However at the NPP’s we have experience removing everything except
RPV
• Internationally, experience exist
Commercial NPPs have been taken out of operation and have partly, or
completely, been dismantled.
Goal
To gather national, as well as international, experiences and lessons learned in
an understandable way, which takes the specific preconditions on the Nordic
market into consideration.
How to collect and document experiences from upcoming
decommissioning in an effective and flexible manner?
Challenge: Lessons Learned
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20302020 2040 20452015 2025 2035
Decommissioning: an area with many challenges
• 100% certainty that the projects will be implemented
• The area is multidisciplinary
• everything from Bq to SEK
• Competence is needed now and for the next 30-40 years!