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Objectives/Scope Refracturing has emerged as a viable option, offering a lower cost to complete a refrac well (approximately $3 million) compared to drilling and completing a new well (approximately $8 million). Refracturing enhances the production of depleted wells and establishes a fracture barrier to manage parent-child interactions. The paper discusses the candidate selection methodology along with operational challenges of refracs. This study also describes how real-time acoustic technology is used to evaluate zonal isolation and quantify the extent to which new rock is being fractured. Refracturing treatment success relies on the ability to create new fractures instead of solely reenergizing the pre-existing fracture network. With immediate feedback, perforation designs can be adjusted to optimize the effectiveness of refracturing efforts. Methods/Procedures/Process A high-resolution pressure transducer located at the surface captures the tube wave that results from any rapid rate change during a fracturing treatment, allowing for a segmented analysis of the signal. Specifically, the slope of the fluid depressurization curve observed during the second segment of the tube wave is used to quantify pipe friction. The amplitude of the reflected wave visible in the third segment is representative of the perforation friction coefficient. This coefficient is linked to the pressure drop caused by perforation impedance, providing insights into perforation friction and perforation efficiency (Dunham et al., 2023). By analyzing various frictional pressures, such as perforation and near-wellbore friction, along with pumping parameters, a diagnostic plot is generated that separates stages based on the quality of zonal isolation. Results/Observations/Conclusions The candidates were selected based on potential EUR uplift which was based on the EUR performance of offset wells with "new-vintage" completion designs. Additionally, defensive re-frac potential was to be evaluated for the child well protection. Well preparation posed major challenges due to highly depleted reservoir, inability to hold a static fluid column, and the toe up inclination of the laterals. Cleanouts were performed with venturi cleanout runs and 4″ liners were landed using heavy weight tubing and hydraulic assist. For refrac diagnostics, a crossplot revealed that the majority of stages exhibited higher near-wellbore tortuosity and breakdown pressure, along with increased post-sand perforation friction. This indicated that the fracture was growing into new rock and overcoming the initiation challenges, as compared to re-energizing the old fractures. This was further supplemented by analyzing treatment pressure trends. Applications/Significance/Novelty Efforts in perforation design aim to prevent overlap with old perforations, but operational challenges such as wireline cable stretch and cement quality make it likely that new perforations will occur at the same depth or close to existing ones. This diagnostic tool is not just useful; it is vital for assessing and optimizing the output of refracturing operations from an operational perspective.