A systematic approach to the selection and qualification of storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere sites and projects for CO2Carbon dioxide geological storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere is provided by the CO2QUALSTORE guideline (Aarnes et al., 2010). Its intention is to harmonise the implementation of CGSCO2 Geological Storage; Injection accompanied by storage of CO2 streams in underground geological formations. in compliance with regulations, international standards and directives while avoiding additional documentation and reporting requirements. This is fully valid also for storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere site remediation, although the authors use the terms contingency, contingency planPlan to implement corrective measures if a significant irregularity occurs, contingency measures, contingency monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions, rather than remediation.
CO2QUALSTORE considers contingency and remediation planning an essential part of the riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event and uncertainty management. Planned contingency measures represent one type of measures aimed at reductionThe gain of one or more electrons by an atom, molecule, or ion of riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event and associated uncertainties. In the bow-tie riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event management model (Fig. 5-3), remediation and mitigationThe process of reducing the impact of any failure measures are part of the consequence reducing measures (right part of the diagram) that are implemented after a feature, event or process (FEP) has occurred. They can be regarded as emergency response measures. A collection of such measures should be assessed and planned in a contingency (remediation) plan. In general, such plans should provide sufficient confidence to the regulators as wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids as to other stakeholders, including the public, that the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere site will provide long-term storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere of CO2Carbon dioxide.
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Fig. 5-3: Bow-tie riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event management model according to CO2QUALSTORE (Aarnes et al., 2010). MitigationThe process of reducing the impact of any failure and remediation are part of consequence reducing measures (right-hand part of the diagram). |
The guideline suggests as a good practice that early warning signals (of an irregularity or leakage(in CO2 storage) The escape of injected fluid from the storage formation to the atmosphere or water column) detected by base case monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions trigger additional contingency monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions, aimed at acquisition of additional data that can be used, among others, to properly select and design remediation measures. The whole process represents a part of the riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event-reductionThe gain of one or more electrons by an atom, molecule, or ion procedure, as illustrated by the riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event reductionThe gain of one or more electrons by an atom, molecule, or ion triangle in Fig. 5-4.
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Fig. 5-4: RiskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event reductionThe gain of one or more electrons by an atom, molecule, or ion triangle according to CO2QUALSTORE (Aarnes et al., 2010). Remediation is shown at the bottom vertex of the triangle |
CO2QUALSTORE recommends that a contingency planPlan to implement corrective measures if a significant irregularity occurs is an integral part of a CO2Carbon dioxide development plan, the basic component of a storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere permit application ( Fig. 5-5). The contingency planPlan to implement corrective measures if a significant irregularity occurs is defined as a plan to implement corrective measures, if a significant irregularityAny irregularity in the injection or storage operation or in the condition of the storage volume itself, which implies the risk of a leakage or risk to the environment or human health occurs. The corrective measures should be prioritised and ranked according to the assessed cost-effectiveness of their riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event/uncertainty reducing effect. In addition, the plan should document that conceivable significant irregularities can be adequately controlled, and express the project developer's commitment to implement appropriate contingency measures, if necessary.
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Fig. 5-5: Components of the CO2Carbon dioxide storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere development plan according to CO2QUALSTORE (Aarnes et al., 2010). |
Appendix B4 of CO2QUALSTORE (Aarnes et al., 2010) provides detailed guidelines on the preparation of the Contingency planPlan to implement corrective measures if a significant irregularity occurs. The plan should be drafted together with another document - the Impact hypothesis. Both documents should be based on the conclusions of basic documents of the previous phase of storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere site development procedure - the Environmental Impact Assessment (EIAEnvironmental Impact Assessment) and the Storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere Performance Forecast (SPF). While the impact hypothesis should focus on measures to prevent significant irregularities under normal operating conditions, the contingency planPlan to implement corrective measures if a significant irregularity occurs should contain corrective measures plan for alternative scenarios (Fig. 5-6). In particular, the plan should describe how to control site performance scenarios that differ from the base case scenarioA plausible description of the future based on an internally consistent set of assumptions about key relationships and driving forces; note that scenarios are neither predictions nor forecasts during the operational lifetime of a CO2Carbon dioxide geological storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere project, and provide assurance that these scenarios can be adequately managed. Both documents together form the project riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event management plan.
The key input to the development of the contingency planPlan to implement corrective measures if a significant irregularity occurs is the riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event and uncertainty assessment, including the assessed effectiveness of riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event/uncertainty reducing measures (safeguards), and the defined project performance targets. Therefore, the process of developing the plan should start by reviewing the results of the riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event and uncertainty assessment. For each of the identified risks, a list of associated safeguards should be compiled. Moreover, a rough estimate of the costs of each safeguard should be provided in order to be able to rank(coal) Quality criterion for coal the corresponding cost-effectiveness of alternative safeguards.
The contingency planPlan to implement corrective measures if a significant irregularity occurs should demonstrate that the collection of safeguards provide adequate assurance that the worst-case scenarios associated with the identified risks can be adequately controlled. For this purpose, it may be useful to classify the safeguards according to their objectives. For instance, it should be demonstrated that all safeguards aiming to manage and constrain reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids pressure together provide adequate assurance that pressure can be properly controlled.
The contingency planPlan to implement corrective measures if a significant irregularity occurs should describe contingency measures for a sufficiently broad range of alternative site performance scenarios, and provide rough estimates of the associated costs.
In general, current regulatory frameworks and supporting guidelines tend to a consensus that approaches for proper site management procedures must be tailored to the unique characteristics of each site (i.e., they should be site-specific). RiskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event-based approaches are promoted. These approaches direct attention towards the most significant risks, as opposed to consequence based approaches that direct attention towards events with the largest consequences. This gives more flexibility in the project design to project developers, and more influence on project management to the regulators. The riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event-based approaches also give an incentive to reduce risks beyond established minimal thresholds. Acceptable riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event levels, accompanied by proper remediation (contingency) plans, should be defined on a case by case basis for each project through an interactive dialogue between regulators and project developers (Aarnes et al., 2010).
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Fig. 5-6: Workflow for preparation of the Impact hypothesis (IH) and Contingency planPlan to implement corrective measures if a significant irregularity occurs (CP) according to CO2QUALSTORE (Aarnes et al., 2010). |
It also needs to be taken into account that the whole cycle of site characterisation, riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event-assessment (including contingency and remediation planning) and monitoringMeasurement and surveillance activities necessary for ensuring safe and reliable operation of a CGS project (storage integrity), and for estimating emission reductions and verification(CO2 storage) The proof, to a standard still to be decided, of the CO2 storage using monitoring results; (in the context of CDM) The independent review by a designated operational entity of monitored reductions in anthropogenic emissions is a continuous process that extends throughout the project life-cycle. This means, among others, that all the relevant documents, including remediation (contingency) plans, should be periodically revised, according to the improved knowledge of the reservoirA subsurface body of rock with sufficient porosity and permeability to store and transmit fluids and its behaviour.
It is probable that a review and update of the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere permit is required during the operational phase. For instance, the EU CCS DirectiveDirective 2009/31/EC of the European Parliament and of the Council of 23 April 2009 on the geological storage of carbon dioxide (2009) requires a permit review not more than five years after issuing the permit and then after every 10 years. Moreover, a review, update or withdrawal of the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere permit can be ordered, based on subject to certain criteria, incl. a leakage(in CO2 storage) The escape of injected fluid from the storage formation to the atmosphere or water column or significant irregularityAny irregularity in the injection or storage operation or in the condition of the storage volume itself, which implies the risk of a leakage or risk to the environment or human health.
The US EPA rule (USEPA, 2010) suggest similar criteria and periods for permit review, although the injectionThe process of using pressure to force fluids down wells permit is issued for the operating life of a CGSCO2 Geological Storage; Injection accompanied by storage of CO2 streams in underground geological formations. project. In case of significant irregularities, leakage(in CO2 storage) The escape of injected fluid from the storage formation to the atmosphere or water column, altered operation conditions, understanding that the storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere integrity may be compromised or that the permit conditions may have been breached, a re-qualification of the permit is necessary.
Besides the above, other available general regulations and standards that are in broad agreement with the CO2QUALSTORE guidelines include the IEAInternational Energy Agency CCSCarbon dioxide Capture and Storage Model Regulatory Framework (IEAInternational Energy Agency, 2010), the Canadian standard on CO2Carbon dioxide storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere CSA Z741 (CSA, 2012) and the more general riskConcept that denotes the product of the probability of a hazard and the subsequent consequence of the associated event management ISO 31000 (ISO, 2009).
The next section focuses on the regulatory regimes that are in place in various parts of the world where CO2Carbon dioxide storage(CO2) A process for retaining captured CO2, so that it does not reach the atmosphere activities are on-going or likely to start in near future (Europe, USA, Canada and Australia).