[en] Beacuse of the wide variations in soil and waste characteristics, the degree of radionuclide retention would be expected to vary; knowledge of that variation may be of value in predicting radionuclde mobility. This report discusses results of investigations of radioactive waste/soil interactions as they relate to radionucldie retention and its variability among soils and radionuclides. In soil column leaching studies, radioactive waste solutions were applied to four different soil types; ²⁴¹Am, ⁸⁸Y, and ¹⁷²Hf were retained in the top four cm of soil with better than 90% retained by a protective surface sand layer. Less than 50% of the ⁸⁵Sr, ¹³⁷Cs, and ⁸³Rb was retained by the surface sand. No ⁸⁸Y, ¹⁷²Hf, ⁸⁵Sr, ¹³⁷Cs, or ⁸³Rb was detected by gamma counting in the leachate solutions, however, using a more sensitive analytical technique small amounts of ²³⁸Pu, ²³⁹²⁴⁰Pu and ²⁴¹Am were found in leachates from all soils. It appears that release of this small fraction of mobile radionuclide may have a significant long-term impact on the environment. It aslo appears that reliance for attenuation of some radionuclides can not be placed solely on characteristics of the soil matrix