Experiments have been conducted to study the diffusion of iodide, cesium and strontium ions through intact and fractured rock samples of charnockite rock formation present at Kalpakkam, India. The diffusion coefficient (Di) of these ions for the intact and fractured rock samples has been evaluated and is found to be ranging from 0.76·10–14 to 6.25·10–14 m2/s and 0.67·10–9 to 84.6·10–9 m2/s, respectively. The study reveals that despite the sorbing nature of Cs and Sr, these ions diffuse comparatively faster than the iodide ion (non-sorbing) through the intact and fractured rock mass. The results have been validated vis-à-vis those reported in the literature and a good agreement has been noticed. This paper deals with details of the testing methodology developed to assess the radionuclide migration as well as the rock mass suitability for safe disposal of the radioactive waste.