The document summarizes the presentation "CCS Risk Analysis" given by Neil Wildgust of the Global CCS Institute. The presentation covered risks associated with various aspects of carbon capture and storage (CCS), including capture, transport, and geological storage of CO2. It discussed approaches to assessing and modeling risks, using natural analogs to understand potential impacts, and monitoring and mitigation strategies. The goal of the risk analysis is to evaluate CCS projects and ensure 99% of stored CO2 remains contained for 1,000 years with 80% confidence.

1. CCS Risk Analysis
Neil Wildgust, Global CCS Institute
Advanced Workshop for CO2 Storage
August 26-17, 2014
DF IPN ESIA Ticomán Auditorium
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2. Structure of presentation
1. Introduction to risk assessment
2. Properties of CO2
3. Risks associated with CO2 capture
4. Risks associated with CO2 transport
5. CO2 geological storage risks
o Performance assessment/predictive modeling
o Potential impacts
o Risk management (monitoring, mitigation)
6. Case Study
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3. 1. Risk assessment
• Technical meaning of risk
(probability, magnitude of impact)
• Risk assessments provide a structured approach to
project evaluation
• Part of a wider risk management process
• Widely applied to industrial projects, environmental
assessments, etc
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4. Fundamental RA considerations
• Context
• Purpose
• Scope and Objectives
• Methodology
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5. Example: UK landfills
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6. UK landfill approach
• Conceptual model
• Screening assessment: Source-pathway-receptor
analysis
• Simple risk assessment
• Complex risk assessment (probabilistic)
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7. Landfill conceptual model
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8. 2. Properties of CO2 and associated substances
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CO2
H2S
SO2

9. Impairment
• CO2 can be tolerated in quite high concentrations
without permanent risk to health.
• BUT if those exposed have key tasks to execute
their response may be impaired.
• THUS need to consider effects during emergency
situations.
Atmosphere in submarines is typically 4000ppm CO2!!
Just below the TLV. Crews should not be impaired.
However levels up to 10,000ppm are reported.
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10. 3. CO2 capture risks
• The risk of scaling up the capture plants (Will the capture process work on large scale? More
demonstration projects are needed to eliminate this risk).
• The risk of fully CCS integrated system and influence on the power plants:
o The power plant ability and flexibility to provide electricity without CO2 capture (capture no capture option)
o The risk of shutting down the whole power plant if a problem occurred in the capture plant (This might occur if the
power plant is fully integrated with the capture process (e.g. pre combustion) or because it could not cope with the
regulation of low CO2 emissions anymore after the failure of the capture plant).
• Specific technical risks per capture technology:
o Post combustion capture: solvent degradation and equipment corrosion
o Oxy-fuel combustion capture: boiler operation (burner design, flue gas recycle, temperature control and preventing air-in
leakage)
o Pre-combustion capture: hydrogen rich turbines operation and availability.
• The risk of integrating the capture process to the power plant (e.g. steam extraction issues).
• Environmental impact: chemical emissions to air, water and land, and overall life cycle of the facility
(e.g. increase fuel consumption).
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11. 4. CO2 transport hazards
• Low temperature releases
• High pressures
• Corrosion
• High vapour density
• Detection issues
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12. SUPPORTED BY:
15 January 2009 Vancouver-line rupture
A running fracture –
result of a test
Fractured gasoline line –
undetected damage
Results of metal embrittlement

13. 5. Geological storage risks
• Predictive modelling of reservoir (‘performance
assessment’), leakage scenarios and potential
subsurface impacts
• Experiments and natural analogues used to assess
potential impacts of leakage scenarios
• Both elements combine for a storage risk
assessment
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14. Predictive modelling
• Can vary from simple analytical equations to
complex numerical models.
• Based on knowledge from oil and gas industry,
hydrogeology, theory.
• Knowledge gained from recent experimentation
and early demonstration projects.
• Required by regulators.
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15. Modelling example
Courtesy Permedia Research
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16. Modelling challenges
• Coupling of processes
• Effects of other substances
• Old/abandoned wells
• Effects of pressurisation and fluid displacement
• Calibration of models – need more real projects to
provide monitoring data
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17. Potential impacts
• Good site selection means minimal probability of
leakage
• But need to know ‘what if ?’………
• Data from natural and industrial analogues
• Laboratory experiments and models
• Controlled field tests
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18. Leakage scenarios
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19. University of Nottingham
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20. The Latera caldera
• The Latera caldera is about 150 km NW of Rome
• Gas seeps occur throughout the heavily cultivated valley
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Prof Lombardi. URS

21. Latera – leakage pathways
0 100 200 300 400 500 600 700
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1500
1000
500
0
CO2 flux (g m-2 d-1)

22. U.R.S – Panera, Italy
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23. U.R.S.
The impact of the gas is limited. Schools of fish swim around the gas plume
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24. Crystal Geyser, Utah, USA
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25. Monitoring and mitigation
• Monitoring techniques established and
demonstrated
• Monitoring provides stakeholder reassurance and
regulatory compliance
• Mitigation strategies will be site-specific
• Experience from CO2-EOR industry
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26. SUPPORTED BY:

27. Conclusions
• Capture and transport risks can be managed with
existing engineering knowledge
• Geological storage risks are site-specific
• Predictive models provide performance
assessment
• Monitoring provides model calibration
• Analogues provide information on potential impacts
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28. Location
ALBERTA
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MANITOBA
MONTANA
WYOMING
NORTH DAKOTA
SOUTH DAKOTA
EDMONTON
SASKATOON
WINNIPEG
REGINA
HELENA
BISMARCK
PIERRE
CALGARY
WILLISTON BASIN
HUDSON
BAY
SASKATCHEW
AN
WEYBURN

29. Weyburn oilfield
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30. RA and Geological Storage of CO2
104% Increase 670% Increase
And for just the final? year of each
Phase: 2004 – 4 and 2011 – 57
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1,325% Increase

31. Geological integrity
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• Reservoir
Characteristics
• Regional
Characterization
• System Model
• Natural Analog
• Mississippian
hydrogeology
• Aquitard
characteristics
• Assessing
movement between
reservoir and
biosphere

32. Containment vs biosphere rocks
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33. Background – Geosphere
Geosphere risk assessment focuses on the deep subsurface and
aims to identify and assess:
• Assess the risk of CO2 escaping from the primary containment
structure and reaching the biosphere (containment risk).
• Assess the effectiveness of the Project in storing the target
volume of CO2 within the confines of the Weyburn unit
(effectiveness risk).
• Identify areas where further research is required to address
areas of high uncertainty.
• Identify actions required to reduce risk, and areas where
further research to develop risk management actions, is
required.
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34. Background – biosphere
Biosphere risk assessment focuses on surface and near
surface processes and aims to assess:
• Likely movement of CO2 within various components of
the biosphere once it reaches the biosphere; and
• Potential impacts on flora, fauna, people and property.
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35. Containment risk targets
The mass of CO2 retained after 1,000 years should be at least 99% of the
total CO2 that will be present immediately after the period of injection.
• Therefore, if the CO2 mass in place at the conclusion of EOR is
approximately 30 million tonnes, the maximum acceptable mass of CO2
lost from the system over the next 1,000 years is 300,000 tonnes (1% of
30 million tonnes). The Project has defined non-containment as any
mass of CO2 that has left the geosphere and entered the biosphere.
The minimum level of confidence that the target volume of CO2will be
retained was set at 80%. Therefore, the maximum chance of losing more
than the target volume of CO2 over the project period is 20%.
• The target risk quotient (likelihood x consequences), is therefore 60,000
for the project (0.2 chance over 1,000 years x 300,000 tonnes).
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36. Process: Geosphere and Biosphere risk
Building Capacity
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36
Geosphere Risk
Assessment
Technical Inputs
• Wellbore integrity research
• Characterisation of reservoir characteristics & transport of CO2
• Seismicity of area
• Characterisation of CO2 reactions in reservoir
• Monitoring techniques & effectiveness
Outputs
• CO2 risk events (initiating event & pathway) & ranking
• Mass of CO2 released if event occurs
• Likelihood of each event occurring & releasing CO2
Biosphere Risk Assessment
Other Technical Inputs
• Characterisation of aquifers
• Characterisation of surface water
• Characterisation of soils / sediments
• Behaviour of CO2 in soils, sediments, groundwater, surface
water
• Receptors in environment
• Toxicology (animal, plant, human)
Outputs
• Risks to biosphere assets (ranking & severity)
Stakeholder
Engagement
Stakeholder Values
to Engage
Acceptability of
Risks
Mitigation Measures

37. Guide to assist in the quantification of likelihood
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38. Containment risk profile
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39. Identifying Biosphere assets most at risk from
pathways
1000
100
10
1
0.1
0.01
0.001
0.0001
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Initiating Events - Risk to Assets
0.00001
EOR Minor faults
EOR Through faults
Nat Seismicity-fault
reactivation
Nat Seismicity-new
fracs
Nat Seismicity-wells
EOR Induced chem-fracs
EOR Induced P/T-fault
reactivation
EOR Induced P/T-new
fracs
Wells Micros fracs,
annuli
Wells Casing
corrosion
Wells cement
Risk Level
Illness, injury, fatality
Tourism
Oil and gas
Agriculture
First Nation heritage
Heritage
Amenity - sensory, perception
Amenity - recreation
Species
Habitat, communities,
assemblages
Ecosystem function
Property/infrastructure
Target Risk Level

40. Update on RA methodologies
• Recent project assessments, e.g. Shell Quest,
Aquistore, Bell Creek
• CSA Standard (joint US-Canada work)
• US DOE & Weyburn Best Practice Manuals
• EC Storage Directive Guidance
• Many other R&D projects and programs…
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41. End.
Advanced Workshop for CO2 Storage
August 26-17, 2014
DF IPN ESIA Ticomán Auditorium
SUPPORTED BY: