Table of contents : Contents Light Drilling, Well Completion and Deep Monitoring 1 Introduction 2 Hontomin Well Drilling 2.1 Goals and Constrains 2.2 Drilling Rigs 2.3 Workflow 2.4 Well Completion and Deep Monitoring 2.5 Coring 2.6 On-Site Tests 3 Performance Curves and Cost Saving 4 Existing Technological Gaps 4.1 Gaps Related to Operation Efficiency and Safety 4.2 Gaps Related to Well Completion and the Installation of Monitoring Devices 4.3 Gaps Related to Rig Instrumentation and Operation Control 4.4 Directed Drilling 5 Future Works 6 Concluding Remarks References Well Logging in Fractured Media 1 Introduction and Scope 2 Overview of Wireline Logging Techniques 2.1 Types of Logs 2.2 Types of Analyses 3 Best Practices 3.1 Data Quality Assurance/Quality Control (QA/QC) 3.2 Analysis Workflow 4 Well-Log Interpretation Case Study 4.1 Study Area and Geology 4.2 Description of Data 4.3 Porosity Analysis 4.4 Integration of Log and Core Data 4.5 Facies Analysis 4.6 Fractures and Vugs 5 Application of Machine Learning Techniques 5.1 Machine Learning Basics 5.2 Example—Vug Characterization 6 Concluding Remarks References Laboratory Scale Works 1 Introduction 2 Petrophysical Characterization Goals 3 Sampling Methodology 4 Tests to Determine Injectivity and Trapping Mechanisms 4.1 Routine Tests 4.2 Injection Under Reservoir Condition 5 Impacts of Impurities 6 Water Analysis 7 Competency of Seal-Reservoir Pair 8 Concluding Remarks References On-Site Hydraulic Characterization Tests 1 Introduction 2 Hydraulic Characterization Goals 3 Challenges to Overcome 4 Inputs from Laboratory Works 5 Tests While Drilling 5.1 Permeability Test 5.2 Connectivity Test Inter-Wells 5.3 Leak-Off Test 6 Test to Determine the Injectivity in the Reservoir 6.1 Brine Injection 6.2 Co-injection of Brine and CO2 7 Modeling and Data Interpretation 8 Concluding Remarks References Safe and Efficient CO2 Injection 1 Introduction 2 Safety and Efficiency Criteria During Injection 3 Case Study: Project OXYCFB300 4 Input from Hontomín Hydraulic Characterization 5 Spanish Patent ES 201500151 5.1 Injection Process 5.2 Operating Parameters 6 Which Brine Alternating Gas Injection Entails 7 Mitigation Tools for the Operational Risks 7.1 How to Preserve Safe Pressure Values 7.2 The Effects of Impurities in the CO2 Stream 8 Concluding Remarks References Modeling Aspects of CO2 Injection in a Network of Fractures 1 Purpose of Modeling 2 Analytical Approaches 2.1 Concept of Injectivity Index 2.2 Applications 3 Numerical Approaches 3.1 Single Equivalent Continuum 3.2 Dual Continuum Approach 3.3 Discrete Fracture Models 4 Concluding Remarks References Risk Assessment and Mitigation Tools 1 Introduction 2 General Elements of Risk Analysis and Assessment Methodologies 2.1 Analysis and Evaluation of Environmental Risks in Geological Storage of CO2 3 Risk Assessment of a CO2 Geological System 3.1 Application of the Environmental Evaluation of HSE Risks in the Site Selection Phase 3.2 Environmental Risks Assessment Using Bayesian Networks 4 Estimators of the Behavior of a CO2 Storage Complex 4.1 Indicators of Seal Formation Performance 4.2 Indicators of the Storage Formation Performance 5 Monitoring, Verification and Mitigation Tools 5.1 Methodology for the Measurement of CO2 Leakages and Dissolved and Free Associated Gases 5.2 Mitigation Tools 6 Concluding Remarks References Risk Communication and Stakeholder Engagement in CCS Projects. Lessons Learned from the Compostilla Project 1 Introduction 2 Lessons from the Experiences Around the Compostilla Project 3 The Methodology 4 Tierra de Campos, Sahagun (Leon), a Case Study 5 Conclusions References