Radium and potassium-40 in solid wastes from the oil industry.

Activity concentrations of (226)Ra, (228)Ra and (40)K in scales and sludge generated during oil extraction and production operations were determined using an HPGe gamma spectrometric system. Concentrations ranged from 42.7 to 2110.0 kBqkg(-1) for (226)Ra, 40.5 to 1550.0 kBqkg(-1) for (228)Ra and 20.6 to 186.6 kBqkg(-1) for (40)K. The magnitude of these results demonstrates the need of screening oil residues for their radionuclide content in order to decide about their final disposal.