ISO/TR 27926:2024 — Carbon Dioxide Capture, Transportation and Geological Storage — Storage Site Management

1. Introduction to Storage Site Management and ISO/TR 27926

The long-term security of CO2 geological storage depends not only on proper site characterization and well construction but critically on how the storage site is managed throughout its operational life and after closure. ISO/TR 27926:2024 addresses this management dimension by providing comprehensive guidelines for the planning, implementation, and oversight of CO2 storage sites. As a Technical Report developed by ISO/TC 265, it complements the more prescriptive requirements of ISO 27914 by providing operational context and implementation frameworks.

The standard covers the full storage project lifecycle from operational planning through injection management, monitoring program implementation, data management, corrective action planning, and transition to site closure and post-closure stewardship. It recognizes that effective site management requires integration across technical disciplines (geology, reservoir engineering, geophysics, geochemistry) and management functions (risk management, quality assurance, regulatory compliance, stakeholder communication).

2. Operational Planning and Management System

2.1 Storage Management Plan

The standard requires that a comprehensive Storage Management Plan (SMP) be developed before injection operations begin. The SMP must integrate all aspects of storage site operations, including injection management, monitoring program execution, data acquisition and management, risk management, corrective action procedures, and communication protocols. The standard provides a structured framework for the SMP with defined sections covering: site description and operational limits, organizational structure and responsibilities, operational procedures, monitoring program, risk register and corrective actions, performance metrics, reporting requirements, and contingency planning.

2.2 Performance Metrics and Key Performance Indicators

ISO/TR 27926 introduces a set of recommended performance metrics and Key Performance Indicators (KPIs) for storage site management. These are organized into categories: containment performance (pressure behavior, plume extent vs. predictions), injection performance (rate, pressure, wellhead temperature), monitoring system performance (data availability, measurement quality), and operational performance (uptime, regulatory compliance). The standard emphasizes that KPIs should be site-specific, measurable, and linked to defined thresholds that trigger review or corrective action.

3. Data Management and Quality Assurance

3.1 Data Acquisition and Management Framework

CO2 storage projects generate diverse data types over extended periods — geological models, injection records, pressure and temperature data, seismic surveys, geochemical samples, well integrity test results, and environmental monitoring data. ISO/TR 27926 provides a structured framework for data management throughout the project lifecycle. The standard requires a Data Management Plan (DMP) that specifies data types, formats, quality standards, storage systems, access controls, and archival procedures. A particularly important requirement is the preservation of pre-injection baseline data, as these form the reference against which all future observations are compared.

3.2 Quality Assurance and Quality Control

The standard establishes QA/QC requirements across all storage site operations. QA covers the management system and processes (organizational structure, procedures, training, audits), while QC covers technical activities (measurement verification, data validation, instrument calibration). The standard emphasizes that QC must include both field measurements and laboratory analyses, with documented traceability to reference standards. Regular audits of the monitoring program, data management system, and operational procedures are required to verify that the management system is functioning as intended and to identify opportunities for improvement.

4. Corrective Action and Contingency Planning

ISO/TR 27926 provides detailed guidance on corrective action planning, building on the framework established in ISO/TR 27923. The standard requires that the corrective action plan address a hierarchy of potential issues: monitoring system malfunctions (instrument failure, data loss), injection anomalies (rate or pressure deviations), well integrity concerns (casing pressure, cement failure), and containment anomalies (unexpected pressure behavior, unexpected plume migration). Each corrective action must be graded by urgency and severity, with clear escalation procedures. The standard also addresses contingency planning for more severe scenarios, including loss of containment and induced seismicity.

5. Transition to Closure and Post-Closure Stewardship

5.1 Closure Qualification Process

The standard outlines a structured closure qualification process that begins years before planned cessation of injection. The process involves demonstrating that the storage complex is behaving as predicted, that the CO2 plume has stabilized or is following a predictable migration path, that formation pressures are declining, and that no leakage pathways exist. Closure milestones include: cessation of injection, well abandonment (permanent plugging), surface facility decommissioning, and regulatory transfer of long-term responsibility. Each milestone requires documented evidence and regulatory approval before proceeding.

5.2 Post-Closure Stewardship

Post-closure stewardship covers the period after site closure when active management is reduced but monitoring and reporting obligations continue. The standard provides guidance on developing a post-closure stewardship plan addressing monitoring frequency (typically reduced from operational levels), records preservation (geological and operational data must be preserved for future generations), financial assurances (funding for long-term obligations), and institutional controls (land use restrictions, notification mechanisms). The standard recognizes that post-closure periods may extend for decades to centuries, requiring stewardship arrangements that are robust and enduring.

6. Frequently Asked Questions