In situ leaching (ISL) is the most popular method for uranium mining worldwide, particularly in arid and semi-arid regions. Despite its economic benefits, ISL raises concerns about radioactive migration and groundwater contamination. This review assesses the environmental impacts of ISL uranium mining, focusing on radionuclide transport pathways and key information gaps. This review, focusing on groundwater contamination, radionuclide migration, soil and sediment contamination, atmospheric impacts, vegetation responses, and ecosystem disturbances, summarizes current understanding of the hydrogeochemical, radiological, and environmental impacts of uranium mining. The analysis indicates that groundwater is the environmental component most vulnerable to contamination during ISL operations due to the injection of acidic or alkaline leaching solutions that may mobilize uranium, radium, sulfates, selenium, arsenic, and other potentially hazardous elements. In addition to impacts on groundwater, there have also been reports of soil contamination, airborne dust, radioactive accumulation in flora, and impacts on aquatic and microbiological resources, particularly in arid and semi-arid regions. Although cleanup methods and natural attenuation can minimize contamination to some extent, residual contamination can persist for decades after mine closure. Overall, ISL uranium mining emphasizes the need for effective groundwater management, long-term environmental monitoring, and improved reclamation methods, balancing surface disturbance with long-term hydrogeochemical and environmental concerns.