RISK ASSESSMENT? IEA JOINT NETWORKS WORKSHOP June, 2008, New York

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1 RISK ASSESSMENT? Estimation of risk is usually based on the expected value of the conditional probability of the (risk) event occurring, times the consequence of the (risk) event given that it has occurred

2 Risk Assessment for Storage Site Characterisation John Kaldi CO2CRC at University of Adelaide

3 Site Characterisation (after CO2CRC, 2006) The collection, analysis and interpretation of subsurface, surface and atmospheric data (geoscientific, spatial, engineering, social, economic, environmental) and the application of that knowledge to judge, with a degree of confidence, if an identified site will geologically store a specific quantity of CO 2 for a defined period of time and meet all required health, safety, environmental and regulatory standards. CO2CRC CO2CRC. All rights reserved.

4 Scales of Investigation Country/State/Region Screening Basin Assessment Site Characterisation Site Deployment)

5 Storage Capacity Estimation Techno-Economic Resource-Reserve Pyramid for CO 2 Storage Capacity Modified from Bachu et al., CSLF, 2005

6 Combined Site & Capacity Evaluation Decreasing Uncertainty; Increasing Data / Effort Required

7 Risk-Based Decision Making in CCS Project Development Pre-Injection Injection / Post Injection Bowden and Rigg, 2003)

8 Resource / Reserve Evaluation Aim: Approval for permit acquisition for CCS Requirements: Qualitative evaluation of source-sink needs (See Bradshaw et al, 2002) Storage capacity (estimate total pore volume) Potential site identification (site ranking see Bachu 2003 Transport (determine potential distances/costs to sites) Regional containment risks Geohazards (i.e. volcanism, earthquake) Effective i trap styles, reservoir/seal pairs Existing natural resources (chance of compromising?)

9 Pre-Feasibility / Options Analysis (expert panel) Aim: Demonstration scale assessment Initial Quantitative Risk Analysis (See Bowden and Rigg, 2003) Assessment of available basic data Storage capacity (estimate prospective capacity) Site details (chance economically and technically) Containment Risk Assessment Seals, faults/fracture, well-bores Red flag any: Environmental and social risks Natural resource risks Data gaps / high uncertainty areas Preliminary estimate of project cost including closure

10 Aim: Internal feasibility analysis for Commercialisation Detailed, Quantitative Risk Assessment incorporating: Performance assessment, including newly acquired data, with modelling results Detailed Containment Risk Assessment leakage pathways from primary container Detailed Technical Effectiveness Risk Assessment Consequence analysis Mitigation and remediation analysis Probabilistic and modelled assessment of Contingent Storage Capacity Mitigation for regulatory/social risks Environmental Impact Analysis Initiate Stakeholder Engagement Program Feasibility Analysis (expert panel + modelling)

11 Approvals Aim: External (Regulatory) Approval for Commercialisation Transparent External Qualitative Risk Assessment (i.e. Environmental Impact Assessment) incorporating: Leakage Risk Assessment on all data available Leakage to surface / near surface / existing resources Consequence ence analysis Mitigation and remediation analysis (technical) Mitigation for social risks Finalise stakeholder engagement program Clarify liability pathways

12 Construction and Injection (Deployment) Aim: Safely develop injection site and safely inject CO 2 Standard industry equipment with standard procedures to manage and minimise risk of fugitive leakage. Baseline surveys completed Initial gathering of injection and monitoring data

13 Post-Injection and Post Closure Aim: Internal Approval for Site Closure Regulator Approval for Abandonment Demonstration of risk reduction through MMV Based on verification that injected CO 2 complies with modelling Refinement of quantitative risk assessment model Revision of monitoring practices

14 RA for Site Characterisation: Gaps Should we also characterise the CO 2 (the injection gas) in terms of composition, given that differing compositions may react with the storage formation in different ways? Existing wells must be considered as part of site characterisation, but what about planned future wells? Will RA for onshore and offshore characterisation need to meet different requirements? CO2CRC. All rights reserved.

15 RA for Site Characterisation: Gaps (cont.) Will RA for onshore and offshore characterisation need to meet different requirements, given the significant differences? For example Data type and availability M&V technologies that can be deployed Remediation options that may be used The economics of storage will differ The scale of operation will be different The opportunity for test wells prior to injection The use of existing infrastructure The environmental impact The jurisdictional issues State/Federal CO2CRC. All rights reserved.

16 RA for Site Characterisation: Gaps (cont.) Is characterisation an activity that occurs only prior to commencement of CO 2 injection? Or does it also continue (and is refined) throughout the injection phase, and during later monitoring and verification stages? Should we be defining i site characterization ti into 3 phases? -pre-injection - injection - post injection?? Alternatively, is site characterisation the pre-injection phase & site verification (M & V) the injection/post injection phase? CO2CRC. All rights reserved.

17 The Future: Aims & Objectives Develop and get sign-off from all stakeholders on best practice for: Developing a risk assessment scheme to optimise characterising storage sites and estimating storage capacity of those sites Assuring consistency in data compilation, interpretation, modelling etc, to the extent that this is possible, given the variability in the extent and quality of geological & geophysical data Ensuring consistency in characterising storage sites and determining storage capacity across state boundaries, between offshore and onshore. Develop a consistent and readily useable methodology that will ultimately deliver the basis for bankable storage projects in an economical, credible and timely fashion. Potentially develop roadmap to certification!

18 Conclusions There is no such thing as the perfect site; they will be fit for purpose.each with own risk assessment criteria We need to agree what is meant by site characterisation, including when it concludes We need to have an agreed methodology for storage capacity assessment Characterisation is site specific, onshore/ offshore specific and storage type (depleted fields, saline fmn, coal etc) specific; it is therefore essential that we identify commonalities and don t just look for differences (lumpers versus splitters!) Easy to work out what we can do ( stamp collecting ); more difficult (and more essential?) to work out what we don t need to do- otherwise the task will overwhelm us! Geology is only one of the features that determines suitability of a site for CO 2 storage CO2CRC. All rights reserved.