The Eunice Monument South Unit (EMSU) produces from the Grayburg formation in southeast New Mexico. The unit has higher than expected water production and lower than expected oil production since a waterflood was installed in 1986; poor vertical flood conformance is to blame. A major project was initiated in 1996 to characterize the reservoir and improve the flood conformance where possible. Reservoir characterization included mapping high permeability streaks, material balance, and percent pore volume swept calculations. Two techniques, production data diagnostics and injection well diagnostics, were then applied to characterize the performance of individual wells. The subsets of wells that were identified as underperforming by each method were compared and a focus area was selected to pilot test a waterflood conformance correction program. Primary problems discovered included water cycling through high- permeability streaks, water injection into the gas cap, and wellbore zonal isolation problems. The waterflood conformance correction program comprises problem diagnosis, treatment selection and design, treatment execution, and treatment evaluation. Several different treatments (cement squeeze, near-wellbore gel treatment, and deep-penetrating gel treatment) were executed depending on the problem encountered. This program has been implemented on 29 wells in EMSU. Production response to the treatments is discussed. P. 689

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Horizontal wells are well-recognized as one of the most effective innovations in exposing the wellbore to maximum reservoir contact and drainage area to improve recovery economics. It creates lower pressure drop to achieve better productivity compared to vertical/deviated wells. In order to enhance sweep efficiency, horizontal wells can be completed with Inflow Control Devices (ICD). ICD completion creates a more uniform inflow distribution along the production interval of the horizontal well. It aims to delay water breakthrough at high permeability zones and to provide better well clean up at initial production. In general, the performance evaluation shows that horizontal wells with ICD's have better sustained productivity than horizontal wells completed open hole or with screens. ICD completion design was previously done based on near-wellbore data only. A new methodology has been applied by tailoring the ICD completion design with fine-grid dynamic 3D simulation that is fast enough to be used for real-time model optimisation while drilling. 3D simulation enables the optimisation for the number and placement of nozzles and packers by maximising the utilisation of reservoir information. The improvement on delivering ICD completion design also includes torque and drag analysis on every horizontal well candidate. The new ICD completion design workflow has been applied since 2015. The real-time single-well dynamic 3D simulation-based design results in a better understanding of the completion options and their performance predictions. Various ICD completion scenarios, from constant nozzle sizes to varying nozzle sizes, and different packer numbers and placements are simulated. The new 3D simulation tool is able to provide time-lapse effects of cumulative fluid (oil and water) production for different flow rates. Additional pressure drop across the completion is modelled for different nozzle configurations. Based on these simulation results better informed decisions can be made regarding the nozzle sizes and numbers. In addition, the proposed ICD completion run-in-hole tally is evaluated in the torque and drag simulator to ensure the proposed ICD completions can be run to total depth (TD). The results of these two simulation steps are combined to optimize the final ICD completion design.