ABSTRACT PT Pertamina International (KPI) Refinery Unit (RU) II Sungai Pakning is one of the petroleum industry activities located in Riau province. The operational activities of PT KPI RU II Sungai Pakning produce emissions, one of which is CO, NO2, and SO2 pollutants which can have a negative impact on the environment and health. One way to describe air quality is by doing dispersion modelin…