Sites that once hosted nuclear-related activities—fuel fabrication, isotope production, or radioactive-material storage—can retain residual contamination  in soils, groundwater, and building structures long after operations cease. When such a property is classified as a sensitive site , redevelopment demands a rigorous, science-driven approach to protect public health and the environment. Key Challenges Legacy Radionuclides : Cesium-137, strontium-90, uranium, or transuranic