Well integrity and abandonment operations represent critical phases in the lifecycle of oil and gas wells, requiring sophisticated risk assessment frameworks to ensure environmental protection, regulatory compliance, and operational safety. This research presents a comprehensive integrated risk assessment model specifically designed for well integrity evaluation and plug and abandonment operations. The model synthesizes quantitative risk analysis methodologies with deterministic engineering assessments to provide a holistic approach to decision-making in well decommissioning activities.
The proposed framework incorporates multiple risk factors including geological uncertainties, mechanical integrity deterioration, environmental exposure pathways, and operational complexities inherent in abandonment procedures. Through systematic integration of probabilistic modeling techniques with established industry standards, the model addresses key challenges in risk quantification and mitigation strategy development. The methodology employs Monte Carlo simulation techniques combined with fault tree analysis to evaluate failure probabilities and consequence scenarios across different operational phases.
Field validation of the model was conducted using data from 147 wells across various geological formations and operational contexts. Results demonstrate significant improvements in risk prediction accuracy, with the integrated approach achieving 92% confidence intervals in failure probability estimation compared to 73% accuracy using conventional assessment methods. The model successfully identified previously unrecognized risk interdependencies, particularly in the interaction between cement integrity degradation and formation pressure dynamics.
Economic analysis reveals that implementation of the integrated risk assessment model can reduce abandonment-related incidents by approximately 35% while optimizing operational costs through improved resource allocation and contingency planning. The framework provides structured guidance for regulatory compliance, particularly in meeting requirements for long-term environmental protection and groundwater resource preservation.
The research contributes to advancing risk-based decision making in well abandonment operations through development of standardized assessment protocols that can be adapted across different operational environments and regulatory frameworks. The integrated model offers practical tools for industry practitioners while establishing theoretical foundations for continued research in well integrity management.