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Abstract Over the last five years, four different wells presented an integrity issue related to failure of at least one of the primary barriers of the completion and risk was estimated high (H). This work presents a comparative analysis of integrity remediation strategies in high-risk gas wells, focusing on cost-effective and environmental impact (CO2 emission) by comparing Rigless-Rig operations. The study reviews four field cases: one rig workover and three rigless interventions, each one involved integrity deviations such as annular communication (>2000 psi), loss of barrier effectiveness, and risk of collapse. Rigless solutions included cement and resin-cement plugs tailor-made for high pressure (>4500 psi), high temperature (>270°F) conditions, annular isolation above packers, nitrogen assisted cleanouts and contingent stimulations. Integrity diagnostics, operational planning, lab tests, and post-job evaluations were analyzed to assess effectiveness, risk mitigation and production recovery. The methodology integrates pressure testing, production data, costs, and CO2 impact to validate the outcomes. The first well intervention was completed with a workover Rig, the tubing string was pulled out of hole, casing integrity was restored using a casing path and the well was re-completed with a new tubing string. However, this required extensive logistics, high costs, high footprint and prolonged downtime of the well. To find a cost-effective solution rigorous laboratory testing along with coiled tubing simulations were carried out. The lab and simulations results enabled a rigless intervention to restore integrity of the barriers, using E-Line for connecting tubing-annular and coiled tubing to place resin-cement slurries directly into the annular sections, achieving dual barrier isolation with minimal footprint. Field operations proved to be successful in restoring well barriers while being more cost-effective, reducing NPT and HSE exposure. This paper introduces a framework for selecting rigless integrity remediation over traditional workovers. These case studies support broader adoption of rigless strategies in integrity management, especially in mature fields where cost and sustainability are critical.