Analysis of Ra, Th, and Po in water samples and low active effluents from a U mining and milling complex generally involves pre-concentration of samples carried out by co-precipitation or by evaporation. This paper describes an alternative method by way of adsorption of these radionuclides on pyrolusite pebbles in a column and their subsequent elution with dilute HNO3. Ninety-three to 99% Ra, 80 to 87% Po, and 90 to 98% Th could be separated into 300 mL of acid solution from water samples of the order of 10 to 20 L. The method is found to be inexpensive and more convenient than other methods, without sacrificing the efficiency of extraction.